ECON3173 – Cross Section and Panel Data Analysis Individual Project: Guidelines and Questions This document provides guidelines and questions for the Individual Project of ECON3173, which accounts for 40% of the total marks. Honoring the precepts of academic integrity and applying their principles are fundamental responsibilities of all students and scholars at BNBU. You are advised to read through the BNBU Guidelines for Handling Academic Dishonesty file on iSpace before you start your assignment. Any form. of plagiarism or cheating can result in various disciplinary and corrective activities. Using generative AI tools is not allowed. Deadline: by Dec.14, 2025. Submission Method: a) Please submit your typing assignment report in a single PDF file to Turnitin ‘Submission Link: Report’ via iSpace. The file name of your PDF submissions should have the following format: ECON3173_Project_Student ID_Name in Pinyin (e.g., ECON3173_Project_190000001_Mi Lin). b) Save your data and .do file(s) in a zip file. Name your zip file as ECON3173_Project_Student ID_Name in Pinyin. Then, upload your file to ‘Submission Link: Stata Data and Program’ via iSpace. You are expected to submit 2 .do files, namely ParA.do and PartB.do, respectively, should be able to replicate each part of your submitted work. c) Use the ‘ECON3173_Individual Project_Report Template’ file on the iSpace to input your report. Ensure you provide a question number for each part of your work. Format Requirements Cover page: Please enter your name and student ID at the top of the report template cover page, available on iSpace. Word limit: The required minimum word count is 1,500 words, with a maximum of 2,000 words in total, excluding tables, graphs, and appendices. Referencing: Your report should include appropriate references in APA format to a variety of necessary literature sources and a wide- ranging bibliography of academic aspects of economics. Font / Size: Cambria 12 or Times New Roman 12. Spacing / Sides: 1.0 / Single-sided / Single-line spacing between two paragraphs. Pagination required: Yes Margins: At 2.50 to both left and right, and ‘justified’. Project Theme: Access to External Finance and Firm Performance Introduction: In this project, you are invited to empirically investigate the determinants of financial access and its subsequent causal impact on firm performance (measured by Sales) using the World Bank Enterprise Survey Data (WBESD). One of the most cited constraints for firms in developing economies is a lack of access to external finance. You will test whether alleviating financial constraints (e.g., gaining access to credit) causes firms to expand output. The project is divided into two analytical stages: l Determinants of Credit: Using cross-sectional techniques to model the probability of a firm having a loan; l Impact of Credit: Using panel data techniques to test if gaining access to credit causes firms to expand output. The WBESD database collects information on firm performance, growth, and related factors. The entire database is available to researchers and includes all survey questions at the firm level. Guidelines to download and prepare data for this individual project: a) Please visithttps://login.enterprisesurveys.org/to register your user account for the WBESD database (see the snapshot below). Registration is free. b) There are a total of 168 economies represented in the World Bank Enterprise Surveys Database (WBESD). Among these, 83 economies have a time span of at least three years. For their individual projects, students are required to use data from a panel of random combinations of three different economies out of the 83 economies. Data allocation protocol: Students must first pick a lottery ticket number. An “Individual Project Lottery Ticket Sign-up Sheet” will be available in iSpace from 9 p.m. on Friday, 28/11/2025. Please sign up for a lottery ticket number by Sunday, 30/11/2025. We will operate on a 'first-come, first-served' basis. A lucky draw will be conducted in class on Monday, 01/12/2025, to assign specific economies to each lottery ticket number. c) Once registration is completed, log in and download the data following the steps below: i. Login with your username and password. You will be directed to the ‘Full Survey Data’ page. ii. Select ‘Panel data’ under ‘Survey Type’ on the left. Ensure you are on the ‘Data by Economy’ view instead of ‘Combined Data’. See the snapshot below. iii. Download your economies’ corresponding data and documentation for all the available years. For example, Afghanistan has two panel data files, one for 2005 and 2009, and the other for 2008, 2010, and 2014. Then download both of them. iv. Extract the data and survey documentation files into a working folder on your PC. The data file is now ready to open in Stata. d) Appendix A at the end of this document offers guidelines for data construction and cleaning when working with WBESD data. Read it carefully before you begin. Answer ALL of the Following Questions Note that this is not an essay-type assignment. Please answer the questions one by one. For each question, the performance of the Stata do files accounts for 20% of the marks. Support your answers with regression tables, graphs, Stata output, and explanations/discussions. Part A: Data Management and Exploratory Analysis (15%) Q1 (5%) Data Preparation: Use the Stata command “append” to combine data from all years and all the selected economies into a single Stata data file with a panel data format and complete the following data preparation tasks: ● Select and rename the variables according to Table 1 below. ‘Old name’ refers to the variable name in the original dataset, while ‘New name’ is the new corresponding name to be defined. ● Generate a new dummy variable creditdum: Equals 1 if the firm has a line of credit or loan from a financial institution (k8 = yes); otherwise 0. ● Generate a new dummy variable Femaledum: Equals 1 if the firm has female participation in ownership (b4 = yes); otherwise 0. ● Generate a new variable ln(sales): The natural logarithm of total annual sales. Table 1: Variable List Survey Questions Old name New name The year the survey was conducted year year Panel ID (the same ID for each firm across different years) panelid panelid What percentage of this firm is owned by Private foreign individuals, companies, or organizations % b2b foreign During the past fiscal year, what were this establishment’s total annual sales? d2 sales Total number of permanent, full-time workers at the end of the last fiscal year l1 labor Year of Survey – Year establishment began operations + 1 year b5 + 1 age Q2 (10%) Conduct exploratory data analysis: ● Provide summary statistics for the variables created in Q1. ● Compare the average ln(Sales) for firms with credit (creditdum = 1) versus those without (creditdum = 0). Is the difference statistically significant? ● Briefly comment on the prevalence of credit access across the different economies in your sample. Part B: Cross-Sectional Analysis (20%) Q3 (20%) Determinants of Access to Credit: Before analyzing the effect of credit, we must understand who gets credit. Restrict your sample to the most recent survey year only (treat this sub-sample as cross- sectional data). Estimate the probability of having a credit line based on firm characteristics: pro(creditdumi = 1|x) = F(β0 + β1ln(Labor)i + β2Agei + β3Foreigni + β4Femaledumi) (1) l Estimate the model using both the Probit and Logit estimators. Report the results side-by-side. Compare the Pseudo-R2. Do the models yield consistent inferences regarding significance? l Interpret the coefficient of Femaledumi from the Logit model. Then, calculate and report the average marginal effects for all variables in the Probit model. ● Explain why the raw coefficients in non-linear binary response models cannot be interpreted as simple marginal effects (unlike in OLS). Part C: Panel Regression and Causal Inference (65%) Q4 (15%) Baseline Fixed Effects Model Revert to the full Panel Dataset (all years and all three economies). Consider a standard performance model in which sales depend on labor inputs and firm characteristics. Report all the results side by side. ln(Sales)it = β0 + β1ln(Labor)it + β2Ageit + β3Foreignit + uit (2) ● Estimate equation (2) using OLS, Fixed Effects (FE) estimator controlling for time- invariant individual effects, FE estimator controlling for individual-invariant time effects, and FE estimator controlling for both time and individual effects. Provide examples of individual effects and time effects in the current context. Comment on your regression results. ● Compare the result of the FE estimator controlling for both time and individual effects to a Random Effects (RE) model using the Hausman test. Interpret the test result. ● Comment on the elasticity of sales with respect to labor in your preferred model. Q5 (15%) The Effect of Credit Access (Naive Approach) Expand your model from Q4 to include credit_dum as the mainvariable of interest. ln(sales)it = β0 + β1credit_dumit + yx it + μi + δt + E it (3) ● Explore the WBESD database to include appropriate other control variables based on the literature as you see fit. Give justifications for adding these extra control variables. ● Run the regression and interpret the coefficient β1, and explain the estimated result. ● Discuss to what extent we could use the estimated coefficient on credit_dumit for causal inference? Q6 (15%) Causal Inference: Further Investigation To better address causality, implement a Difference-in-Differences (DiD) strategy focusing on firms that changed their credit status. ● Define a Treatment Group (Firms that did not have credit in period t 1 but gained it in period t) and a Control Group (Firms that never had credit). ● Estimate the standard Two-Way Fixed Effects (TWFE) DiD equation: yit = αi + λt + δDiD(Treati × postt) + βxit + E it (4) ● Report the estimator for δDiD. ● Discuss the Parallel Trends Assumption required for this estimator to be valid. Q7 (20%) Robustness To what extent could we use the estimated coefficient on Treati × postt obtained in Q6 for causal inference? How could we ensure that the Parallel Trends Assumption holds? Is the treatment effect long-lasting? Is the treatment effect homogeneous? Illustrate a suitable empirical strategy for the above questions. Estimate the model using your chosen approach, and compare the results with those from Q6. Interpret and discuss the findings. Explore the WBESD database to include other variables as you see fit. Appendix: Guidelines for Data Construction and Cleaning (Read this carefully before starting your Stata analysis) The World Bank Enterprise Survey Data (WBESD) is a rich resource, but it requires careful cleaning to be usable for empirical studies. Real-world data is rarely “ready to run”. Follow the steps below to construct your dataset. Phase 1: Data Merging and Compilation 1. File Selection: l Do not download single-year cross-section files (e.g., “Vietnam 2015”). l Download the “Panel” datasets. These files usually have names like Vietnam- 2015-2023-Panel-Data.dta. They contain the crucial “panelid” variable that links firms across time. 2. Combining Economies (The append Strategy): l You need three economies. Do not try to merge them side-by-side. You want to stack them on top of each other (long format). l Stata Workflow: Open the first country’s dataset, generate a country ID, save it. Open the second, generate a country ID, append the first, etc. l Code Hint in Stata: use "Vietnam_Panel.dta", clear gen country_name = "Vietnam" save "combined_data.dta", replace use "Senegal_Panel.dta", clear gen country_name = "Senegal" append using "combined_data.dta" save "combined_data.dta", replace 3. Variable Standardization: l Check variable names across countries. While the World Bank tries to standardize (e.g., d2 is always Sales), sometimes older files use d2_2015 or sales_val. l Use the command lookfor sales or lookfor labor to find the correct variable codes in each dataset before appending. Phase 2: Cleaning and Consistency 1. Handling Missing Values and Codes: l WBESD often uses special codes for missing data: o -9 = Don't Know o -7 = Refusal o -8 = Does not apply l Crucial Step: You must convert these to Stata missing values (.) before calculating means or running regressions. If you treat -9 as a real number, your averages will be wrong. l Code Hint in Stata: mvdecode _all, mv(-9 -8 -7) 2. Outliers and Monetary Values: l Sales (d2) are reported in local currency units (LCU). l Do not compare raw nominal sales between Vietnam (Dong) and Senegal (CFA Franc) directly. l Solution: We use log_sales and Country Fixed Effects (or Firm Fixed Effects). The Logarithm roughly normalizes the scale differences. l Winsorizing: Real data often has data entry errors (e.g., a firm reporting 1000% growth). It is good practice to winsorize the top/bottom 1% of continuous variables, such as sales and employee counts. l Code Hint in Stata (requires ssc install winsor2): winsor2 sales, cut(1 99) replace Phase 3: Handling Panel Time Gaps This is the most challenging part ofusing WBESD. Unlike annual stock market data, these surveys happen irregularly (e.g., 2013, 2016, 2020). 1. Declaring Panel Data: l You cannot just use panelid if IDs are repeated across countries (e.g., Firm #1 in Vietnam and Firm #1 in Peru). l Create a unique ID: egen unique_id = group(country_name panelid) l Declare data: xtset unique_id year 2. Defining the "Treatment" (Switchers): l A firm is "Treated" in the DiD sense ifit goes from No Credit (k8=0) in one wave to Yes Credit (k8=1) in the next. l Identify the year the switch happened. Since there are gaps, we assume the switch happened between the survey waves. 3. Imputing Dynamics for Event Studies (this is only relevant if you choose to conduct event studies): l Because you don’t have data for every year (e.g., data exists for t = 2015 and t = 2019, but missing 2016, 2017, 2018), you cannot create a standard “Year-1, Year-2” event plot. l The “Relative Wave” Solution: Instead of "Years since treatment", use “Waves since treatment”. l Constructing the Variable: If a firm is treated in 2019 (it had no credit in 2015, but has credit in 2019): o 2015 is Time t = -1 (Pre-treatment) o 2019 is Time t = 0 (Treatment/Post) o 2023 is Time t = 1 (Post-treatment persistence) Use these “Relative Time” indicators to plot your coefficients if needed. Phase 4: Common Pitfalls to Avoid The “Inconsistent Panel” Trap: l Some firms appear in 2015, 2018, and 2023 but are missing in 2020. l For the First Difference or Lagged models, Stata will drop these firms because it cannot calculate (t) - (t - 1). l Check: Use xtdescribe to see your pattern. Ideally, keep firms that are present in consecutive waves for the DiD analysis. l Creating a Time Index: Do not use the calendar year as your time index for xtset. Instead, generate a sequential Wave Index, e.g., gen wave = . replace wave = 1 if year == 2015 (for example) replace wave = 2 if year == 2028 ... and so on. Use xtset unique_id wave to declare the panel.
Article Review Task i) Think back to the article ‘Differences in managerial Communication: Fact or Folk-linguistics?’ and answer the following questions: a) Who is the author and when was the text published? b) What kind of source is it? c) Has the author conducted their own research? d) Does the author refer to secondary research? e) What are the main points/arguments the author(s) make? Choose two or three. f) Can you relate to the arguments/points made in the article to what you have studied/read, or from your own experience? How? Give specific examples from parts of the text. ii) Read the model answer below and place the question (a-f) next to the part of the paragraph where it is answered. Questions Paragraph The text ‘Gender Differences in Managerial Communication..’ by Smeltzer and Werbel (1986) documents primary research carried out into how men and women may differ in managerial styles. The authors have carried out primary research into this topic and have referred to secondary sources in the literature review and discussion sections of the article. For example, they mention other studies by Bradley (1981, cited in Smeltzer and Werbel, 1986) which corroborates the analysis of their findings. One of the author’s findings was that there were few notable differences in effective communication styles between men and women. They noted that the use of memos and letters to be persuasive were used effectively by both men and women, without any noticeable difference between the genders. Moreover, they state that by claiming stereotypes like this exist, it can lead to ‘self perception […] deficiency’ (Smeltzer and Werbel, 1986: 4) in women and the creation of ineffective management training courses, which can have negative implications for women’s career development. I can relate the point about ‘self-perception deficiency’ as I have witnessed this and heard others talking about this concept in their workplace. When I did an internship at a company in Beijing, I noticed that women often spoke about themselves being unable to do certain jobs such as negotiating in sales deals because they were women. They said they lacked the persuasive skills and necessary language men naturally possessed to carry out this role. I found this attitude difficult to understand and can see how it would lead to people perpetuating a myth based on stereotyping. Another finding from the research was that…. I can relate to this point because/ in that…. In summary, this article indicates that gender has little or no effect on managerial communicative effectiveness. Through extensive and meticulous research, the authors convincingly debunk certain myths surrounding gender roles and stereotypes in the workplace. This article has corroborated some of my own anecdotal opinions on this matter and made me question other stereotypes that are often related to gender and personality. iii) Can you complete the empty paragraphs in this model essay? You need to summarise another point from the article and relate to it in some way. When summarising the main points of the article make sure that you paraphrase and cite properly.
BLE 3022 Effective Writing Assignment 2 (30%) – Writing the Literature Review of an Academic Report (Pair Work) Deadline: Week 11 Purpose This assignment builds on the Introduction you completed in Assignment 1. You will now develop the Literature Review section of your academic report based on the same topic, problem, and research questions previously submitted. The focus of Assignment 2 is to help you: · Synthesise scholarly literature related to your study · Demonstrate understanding of key concepts and research findings · Present information in clear and coherent academic writing following APA 7 style. Task Overview Using your Assignment 1 topic, write: · Literature Review (700-800 words excluding references) · Your literature review must connect logically to your Introduction (Assignment 1). You should show progress from identifying the problem and research gap (Assignment 1) to reviewing the literature. · Use recent academic sources (published within the past 10 years). · You need to submit your Turnitin similarity report with your assignment (maximum 20%) · Upon final submission, your assignment must include: - Cover page - Turnitin similarity report - Literature review - Appendix A SECTION A: LITERATURE REVIEW (20 marks) Your Literature Review must include four (4) major components: No. Element to Include Guiding Questions 1 Overview of the Topic Area · How do scholars define and discuss these concepts related to your topic / research area? 2 Review of Past Studies · What have previous studies found? · What methods did they use? · What similarities and differences appear across studies? 3 Research Gap and Link to Your Study · What is missing or underexplored in past research? · How does your study address this gap? 4 Section headings checklist -Student Contribution · Write your name and student ID to show the parts of the section heading that you have contributed to the Literature Review. · E.g. – 2.1 Maslow’s Hierarchy of Needs (Student Name – 1002xxxxxx) Important: Your review must be written in a synthesised manner and not as separate article summaries. SECTION B: APPENDIX A (10 marks) You are required to include a Literature Review Summary Table as Appendix A at the end of the report (after the Reference List). This table summarises the key studies discussed in your Literature Review and must contain the following six (6) columns: 1. Title 2. Country / Author 3. Type of Source (e.g., journal article, book chapter, academic report) 4. Short Summary – approximately 30 words summarising the study’s purpose, method, and main findings 5. Key Takeaways – the main insights or implications that connect the study to your research topic The appendix will be assessed on clarity, accuracy, relevance, completeness, and effective organisation of information. No. Title Country / Author Type of Source Screenshot of the first page of the journal article Short Summary Key Takeaways 1 2 3 … Requirements Word Count · Total: 700-800 words (Excluding references & appendix) References · Minimum 8-10 academic sources for the Literature Review · All sources MUST be credible (journal articles, books, academic reports) APA 7 · In-text citations and reference list must follow APA 7 · Reference list begins on a new page after Section 3 Formatting · Font: Times New Roman, 12 pt · Spacing: Double · Alignment: Justified · File format: .docx · Title page must include: - Full title of report - Student name - Student ID - Word count Use of AI tools · AI tools may be used ONLY for grammar checks and paraphrasing. · AI-generated content, citations, or ideas are strictly prohibited. Marking Criteria (30 marks) A. Literature Review – (20 marks) Component Description Marks 1. Content Coverage & Synthesis Shows understanding of theories, concepts, and 8–10 studies; identifies research gap; information is accurate and relevant. /8 2. Organisation & Coherence Ideas flow logically, grouped thematically; clear links to student’s research topic. /4 3. Academic Language Clear academic tone, accurate paraphrasing, minimal grammar errors. /4 4. APA 7 & Source Use Correct in-text citations and references; credible sources integrated appropriately. /4 Total: /20 marks B. Appendix A – Literature Review Summary Table (10 marks) Component Description Marks 1. Completeness of Table All 5 columns completed for all entries (title, country, type of source, 30-word summary, key takeaways). /3 2. Accuracy & Relevance Information accurately represents the study and relates clearly to the student’s research topic. /3 3. Quality of Summary & Takeaways 30-word summary is clear, concise, and synthesised; takeaways are meaningful and connected to the literature review. /3 4. Formatting & Organisation Table is neat, readable, and correctly labelled as Appendix A. /1 Total: /10 marks Total: 30% of course grade
CS2400 Group Assignment Creation of a Data Product August 2025 CS2400 Group Assignment (15%) In groups of three students, work on either (A) or (B). (A) Creation of a data product that will help users cope with the rising inflation rate in the coming years. Deadline: 3 November 2025 (Monday) In the past decade, Singapore enjoyed a very low inflation rate of between 0 and 1 percent. Minister Lawrence Wong has warned that in the coming years, Singapore’s inflation rate is expected to rise due to turbulent and uncertain geopolitical environment, issues with supplies, and because Singapore is transitioning to become more sustainable. The inflation rate is also not expected to return to 0 to 1 percent as the past decade was an anomaly. This year, Mr Ravi Menon’s Annual Report Media Conference focused on inflation. He raised a few interesting points: · inflation affects everyone, however, it affects the lower-income groups more · Singaporeans are concerned about inflation · inflation had already been on the rise even before the war in Ukraine, but the war made it worse · the inflation rate is projected to increase to a peak of 4.0-4.5% in Q3 2022 · the inflation rate is expected to come down in 2023, but will remain well above 1.5% Inflation is serious because it directly affects our cost of living. Before the Covid-19 pandemic started, cost of living had already been one of the top concerns not for just for Singaporeans, but for many people around the world. Covid-19 made the problem more serious, and now global events (like the war in Ukraine) has exacerbated the problem further. In Singapore, the issue of cost of living is compounded because of our rapidly ageing population. According to UOB economist Francis Tan, in 2018, the number of people above 65 will equal those under 15 for the first time in history (he referred to this as a “demographic time bomb”). This greying demographic means that we will have an ever-greater proportion of retirees in the population. Retirees are especially hard hit by rising costs as they do not work, and therefore no longer earn a salary. They depend on their life savings and CPF for their day-to-day expenditure, and this is why controlling the cost of living is especially important for them. They are concerned that the purchasing power of money will be diminished if the inflation rate is high as they have to make their savings last. Retirees literally have to stretch every dollar in their savings. Singapore is also vulnerable to increasing food prices because we import over 90% of the food we consume. Relying so heavily on food supplied from overseas means that we face unique challenges, e.g., having to accept prices set by food producers (link). In 2022 and beyond, cost of living is likely to remain a major concern for many households in Singapore, particularly for the low- and middle-income families, and especially for sandwich generation (those with young children and aged parents to care for). This assignment focusses on the financial hardships brought about by inflation. As this is a multifaced problem, it is a complicated one to tackle. However, it is important and for many families, very real. This is why you will be working on it. Format Your report should be a document that aims to convince a venture capitalist to invest in your idea. As this is not the typical academic report (venture capitalists are not interested in reading the usual academic term paper!), the “Introduction ® Literature Review ® Methodology ® Results and Discussion ® Conclusions” need not be followed. In your groups, discuss what format this document should take. To put together a compelling case, you may think of incorporating video or audio. If you decide to include videos in your report, the best tool to use is Adobe InDesign as it allows good control over the placement of the video. Convince a venture capitalist how your data product will help users manage their expenditure, and why people would want to use your data product. Preliminary Work 1. View the following video to understand inflation: https://youtu.be/UMAELCrJxt0 2. Consult Investopedia (https://www.investopedia.com/) and InvestorWords (http://www.investorwords.com/) to understand these economic terms: (a) inflation (b) purchasing power (c) cost of living (d) Consumer Price Index (CPI) 3. Read the articles in Annex A to understand the impact of inflation. 4. Reflect on how rising costs have affected you and your family. Your parents work hard to support the family. Speak to them about inflation to understand the issue from their perspective. 5. Retrieve articles on the impact of inflation on people in other countries from the Nexis Uni database (http://www.ntu.edu.sg/library/). 6. Read What is Data Science? by Mike Loukides (2010) to understand what a data product is. 7. Read How Venture Capital Works by Bob Zider (1998) to understand who a venture capitalist is, and how venture capital works. 8. Think about the structure of a document that a venture capitalist would be attracted to read. This is a person who manages a lot of money, and who is constantly sent all sorts of ideas clamoring for his attention/interest/backing/money. He will spend only a short time on each document (he’s got to get back to monitoring his investments). What sort of report will attract him enough to take a second, third, fourth look, and to ultimately fund your data product? Now, you are ready to start working on your data product. Your objective is to conceptually design (you do not have to do any programming or calculations) a data product that helps to cope with, or betters still, beat inflation in the coming years. You are advised to focus your data product on a particular group of people (e.g., people who have been retrenched, people who have had their salary reduced, retirees, or the 400,000 Singaporeans living on $5 a day, newlyweds, or diabetics, etc.). Working in groups of three (you may choose your own group members), write a 2,700‒3,000-word proposal to a venture capitalist, for a data product that can help make prices more transparent, and in doing so, enable Singaporeans to make better purchasing decisions, and lower their cost of living. This data product can be an app mobile phone, a website, or a combination of both. The aim of your report is to convince the venture capitalist that your data product is worth investing in (in short, you want him to invest in your idea). Think about the contents (i.e., what you will include in the proposal) and a suitable format for your proposal (i.e., how you would organise and present your contents). Remember that you want to win your venture capitalist over – you want his buy-in – you want him to fund the development of your data product. In the past semester, different groups of students have asked if the proposal can include a short video (yes), a recorded interview in the form. of sound clips (yes), flowcharts (yes), infographics (yes), photographs (yes), and screen mockups (yes) in the proposal. Note these points: ± If you are including a video file, save your video in the MP4 format. ± If you are including an audio file, save your audio in the MP3 format. You can then add your video or audio file into your Microsoft Word or Adobe InDesign document. Upload your proposal in the Microsoft Word format (*.docx) or the Adobe InDesign format (*.indd) to NTULearn by 1 November, 2022 (Tuesday). Very Important 1. Upload one file per group. 2. The names of all the group members must be on the first page of the report. Ensure that the names are the same as the ones printed on your matriculation card. (B) Creation of a data product that will help users reduce food OR E-waste. Deadline: 3 November 2025 (Monday) Food Waste Let’s start with a definition of food waste. Food waste refers to food intended for human consumption which is then thrown away. Exactly where is food wasted? Food waste happens at every point along the food supply and consumption chain. This includes food waste from: · farms · processing and transport · hospitality operators (e.g., hotels) · supermarkets · households Because of this, some organisations (e.g., the T.H. Chan School of Public Health at Harvard University) uses different terms to refer to food waste, depending on where it occurs. The term “food loss” is used if the waste occurs before the food reaches the consumer and “food waste” is used when the occurs at the retail or consumption stages. (source) Food waste is one of the biggest waste streams in Singapore, and accounts for about 12 per cent of the total waste generated here. The amount of food waste has grown by around 20% over the last 10 years. In 2019, Singapore generated around 744 million kg of food waste. That is equivalent to 2 bowls of rice per person per day, or around 51,000 double decker buses. (source) The table below shows the amount of food waste Disposed of, Recycled and Generated in the past 5 years. The increase in the amount in each category is staggering. What’s distressing is the low recycling rate (17 – 19% each year). Year Food Waste Disposed of ('000 tonnes) Food Waste Recycled ('000 tonnes) Total Food Waste Generated ('000 tonnes) 2023 623 132 755 18% 2022 667 146 813 18% 2021 663 154 817 19% 2020 539 126 665 19% 2019 607 136 744 18% 2018 637 126 763 17% Food waste is an important problem in Singapore because we import over 90% of our food supply. Imagine this – every day – every single day – we throw away more than 2 million kilograms of food. This is how much less food we have to import if we reduce food waste. In addition, food waste has to end up somewhere. In Singapore, they are typically incinerated. The ash from the incineration plant ends up in a landfill. This puts pressure on land scarce Singapore. This assignment focusses on the problem of food waste. As this is a complex problem involving many areas, it is a complicated, yet important one for Singapore. E-Waste E-waste is electrical and electronic equipment of any kind that has been discarded. It includes practically anything powered by an electrical source (e.g., from a power socket or a battery). Common types of e-waste include the following: q Infocomm technology (ICT) equipment, such as desktop, laptop and tablet computers, mobile phones, computer and mobile phone batteries, printers, peripherals and accessories such as keyboards, modems, monitors, computer mice, docking stations, hard disk drives, battery chargers, etc. q Home appliances, such as TVs, refrigerators, air conditioners, washing machines, rice cookers, microwave and toaster ovens, electric kettles, food processors and blenders, electric fans, DVD/video/music players, radios, hi-fis, vacuum cleaners, etc. q Other types of e-waste include lamps and lighting devices, batteries, electronic toys, sports and leisure equipment, etc. E-waste is mostly made up of metal and plastic components, but also contains small amounts of heavy metals and substances of concern (e.g., in printed circuit boards). The wide variety of e-waste makes it hard to generalise the material content – for example, fridges and air conditioners in particular contain refrigerants to enable cooling to take place, but these refrigerants may also contribute to ozone layer depletion or climate change; the material composition of a mobile phone is very different from that of an electric kettle. A study released in 2018 by Singapore’s National Environment Agency found that the country produces 60,000 metric tons of electrical and electronic waste every year. About 60 percent of Singapore residents do not know or are unsure of how to recycle their e-waste. Format Your report should be a document that aims to convince a venture capitalist to invest in your idea. As this is not the typical academic report (venture capitalists are not interested in reading the usual academic term paper!), the “Introduction → Literature Review → Methodology → Results and Discussion → Conclusions” need not be followed. In your groups, discuss what format this document should take. To put together a compelling case, you may think of incorporating video or audio. If you decide to include videos in your report, the best tool to use is Adobe InDesign as it allows good control over the placement of the video. Convince a venture capitalist how your data product will help users manage their expenditure, and why people would want to use your data product. Preliminary Work 1. View the following videos: a. this video to understand food waste; or b. this video to understand e-waste. 2. Understand why food/e-waste is a problem a. this podcast explains the different problems food waste creates b. this article explains the dangers of improperly disposed e-waste 3. Understand that there are categories of food/e-waste a. avoidable vs unavoidable food waste (article) b. regulated vs unregulated e-waste (article) 4. Read the articles in Annex A to understand the extent and impact of food/e-waste in Singapore as well as around the world. 5. Retrieve articles on food/e-waste from the Nexis Uni database (http://www.ntu.edu.sg/library/). 6. Read What is Data Science? by Mike Loukides (2010) to understand what a data product is. 7. Read How Venture Capital Works by Bob Zider (1998) to understand who a venture capitalist is, and how venture capital works. 8. Think about the structure of a document that a venture capitalist would be attracted to read. This is a person who manages a lot of money, and who is constantly sent all sorts of ideas clamoring for his attention/interest/backing/money. He will spend only a short time on each document (he’s got to get back to monitoring his investments). What sort of report will attract him enough to take a second, third, fourth look, and to ultimately fund your data product?
ECON3183: Time Series Data Analysis Individual Project This document provides questions and requirements for the Individual Project of ECON3183, which accounts for 40% of the total marks. A statement regarding academic honesty and the stance on using generative AI tools in this course: To achieve the desired learning outcomes for this course, students must complete individual assignments, a test, and a term project that involves conducting empirical investigations/studies related to economics or finance. Students are expected to obtain data from a reliable source, perform. exploratory data analysis, propose a causal inference strategy with justification, conduct empirical studies, and interpret the results independently. To ensure that students meet the intended learning outcomes for this course, generative AI tools are not allowed for any submissions (including drafts or final versions) unless otherwise specified in the assessment instructions. All work (including assignment reports, test answers, the term project report, and Stata codes) must be the student’s own or adequately attributed to its source. Using ChatGPT or other AI tools for CA is considered equivalent to receiving help from someone else. It raises concerns that the work is not the student’s own unless the instructor has provided specific instructions to the contrary. Penalties for unacceptable AI use may include resubmitting the work, partial mark deduction, or receiving zero marks for the corresponding CA component. Turnitin’s ‘Similarity Check’ and ‘AI detector’ features will be used to monitor the use of AI tools in this course. Deadline: by Dec. 21, 2025. Submission Method: a) Submit your typing assignment report in a single PDF file to Turnitin ‘Submission Link: Individual Project - Report’ via iSpace. The file name of your PDF submissions should have the following format: ECON3183_Individual Project_Student ID_Name in Pinyin (e.g., ECON3183_Individual Project_190000001_Mi Lin) and b) Save your data and .do file(s) in a zip file. Name your zip file as ECON3183_Individual Project_Programme_Student ID_Name in Pinyin. Then, upload your file to ‘Submission Link: Individual Project - Stata Data and Program’ via iSpace. Assignment Guidelines: Please note that this is not an essay-type assignment. Answer each of the following questions one by one. Modify the STATA example programs from the Lectures on iSpace as needed to address each question. Name your STATA programs (.do files) as “Q1”, “Q2_PartA”, “Q2_PartB”, etc., so that it is easy to match each program with its corresponding answer. Question 1 (20%): Interpret an Existing Study Referring to the paper by Chow and Wang (2010), “The Empirics of Inflation in China”, on the first page, the last paragraph, the authors report that “Let ut = log(pt ) — log(p*t) be the estimated trend deviation of the log price level or the error correction term. We then regress dlog(pt ) on dlog(M2t /yt ), dlog(pt-1 ), and ut-1 where dlog(xt) is defined as log(xt) — log(xt-1), …”. What is “trend” referred to in the first sentence, and for what purpose should it be estimated? Replicate the last two regression results reported at the end of this paper. Illustrate your understanding of this empirical approach. What is the specific purpose of these regressions? How should we interpret the estimated coefficients in this model? Illustrate your understanding that the coefficient on ut-1 is negative. Question 2 (80%): Mini Independent Empirical Study Select an economy that interests you and download data for it from reliable source(s) for the following empirical investigations outlined in Part A and Part B. Each economy can be chosen by only one student. A data sign-up sheet is available on iSpace from 9 pm on November 28, 2025, where you can indicate your choice of economy by November 30, 2025. We will adhere to a ‘first-come, first-served’ principle. It is strongly advised that you verify data availability before finalizing your choice of economy using the data sign-up sheet, just as you would for your Final Year Project (FYP). To ensure fairness, once you register on the sign-up sheet, your chosen economy will be considered final and cannot be changed. Examples of reliable data sources include, but are not limited to: - IMF Data Portal: https://data.imf.org/ or https://data.imf.org/IFS, - World Bank Open Data: https://data.worldbank.org/, - Bank for International Settlements (BIS): https://data.bis.org/topics/EER, - Official Website of the Government Statistics Bureau (e.g., https://www.stats.gov.cn/), - Renowned University/Research Institution’s Website, e.g., UBC Sauder School of Business (maintained by Prof. Werner Antweiler) on exchange rates: https://fx.sauder.ubc.ca/, etc. which are all publicly available databases supplied by experts or organizations with a good reputation in the field, and that provide trustworthy, accurate, credible, and up-to-date information. Using data from non-authority sources could lead to failure in this assessment component. Part A (50%): Download the following variables for an economy of your choice (Domestic) and the United States (Foreign) from reliable data source(s), starting from January 1970 (or as early as possible) to December 2024 (or as recent as possible). • Exchange Rate: Monthly average and daily of the Nominal Exchange Rate (St), defined as units of Domestic Currency per 1 unit of U.S. Dollar. • Domestic Prices: Monthly Consumer Price Index (CPI) for your chosen economy. • Foreign Prices: Monthly Consumer Price Index (CPI) for the United States. Use monthly data for Questions 1 to 3, and daily data for Questions 4 and 5. Provide comments on the results in the context of the economy you chose. 1. Data Preparation and Description (5%): Introduce your data source. Convert seasonally unadjusted CPI data to seasonally adjusted data if the raw data is not already adjusted (Note: Exchange rates typically do not require seasonal adjustment, but verify this for your specific currency). Let pt be the Domestic CPI and pt* bethe US CPI. Calculate the quarterly log-difference for both to derive inflation rates: πt =
Formative Writing Coursework 3 - Basic Proposal Task Description: . Write a Basic Proposal using the provided sources. Due Date: . Week 11 (Friday, 5 p.m.) Core Requirements You must fulfil all core task requirements listed below: . Complete all sections of the basic proposal, including: Proposal Statement (Section 1.0) Background to Proposal (Section 2.0) Benefits of the Proposal (Section 3.0) Conclusion (Section 4.0) . Word count: 400 - 700 words (excluding the title and references). . Use at least TWO of the sources provided. . Use proper referencing and citation. . Do not use direct quotations (i.e. copying an entire phrase or sentence from a source). Learning Outcomes Percentage of Final Mark D. Produce written responses to non-academic and academic tasks with level-appropriate coherence, complexity, and accuracy. E. Demonstrate awareness and understanding of level-appropriate linguistic forms. F. Demonstrate awareness of and ability to utilise a range of academic skills and conventions. Formative (0%) Formatting Requirements This assessment should follow these requirements: . File format: Microsoft Word .doc or .docx . Filename: Formative_3_Your full name (e.g. Formative_3_Dehua_Liu) . Line spacing: 1.5 . Font type: Arial . Font size: 11 Note: Please submit the proposal using Microsoft Word. Do not write your proposal using other applications, such as WPS or Pages, in order to avoid IT issues in the submission dropbox. It is your own responsibility to download the submitted file and check that the submission is a readable file. Further Details . You should complete this writing task individually. . Use sources from the Readings in Weeks 8-10 to support your ideas. . This formative coursework is not assessed (and you will not receive a mark), but you will receive some general feedback on this task. . The topic of the proposal will be related to arts in education. . This writing assignment will help you prepare for the Semester 2 Summative WCW. . In the Semester 2 Summative WCW, you will write a full proposal, which includes one more section, ‘ Implementation’ . This section will be placed before the ‘Benefits’ section (Section 3.0). Suggestions Task: . Include explanations and examples to support the main idea of your paragraph (Unit 3). . Further develop ideas within the body paragraph by using parallel subtopics or investigating a specific aspect of the topic in more detail (Unit 6). . Use a Source Integration Chart (Unit 10) to help identify and arrange ideas from the sources. Organization: . Organize your ideas clearly by using an appropriate paragraph structure (Units 2-3). . Use appropriate cohesive devices (Unit 5). Language: . Follow the Academic Style rules (Unit 1). . Include compound and complex sentences (Weeks 2-3 OLs). . Use the academic vocabulary you have learned this semester from: AWL Sublists 1-3 Weekly Vocabulary List (Units 1-10) Vocabulary journal (Week 4 OL) . Include relative clauses (Week 5 OL). Academic Integrity: . Use multiple paraphrasing methods to integrate source material (Units 8-10). . Use both integrated and non-integrated citations (Unit 8). . Academic Integrity penalties do not apply to this assignment. However, in summative writing assignments, plagiarism, collusion and improper referencing will be penalized. Academic Integrity penalties range from a 5% deduction to an award of 0 (zero).
Assignment Information Module Name: Machine Learning Module Code: 6001CMD Assignment Title: Coursework Assignment Due: 6 pm Monday 1st December 2025 If you do not pass this assessment, you may have an opportunity to resit it. If you do need to resit, you will be asked to use the feedback provided to revise your original submission, so that it meets the pass requirements for the module. You must clearly indicate the changes you have made in the new submission. Please check your SOLAR results and the submission links on your Aula module page to see when the resit is due. Assignment Credit: 20 credits Word Count (or equivalent): 2500 words Assignment Type: Percentage Grade (Applied Core Assessment). You will be provided with an overall grade between 0% and 100%. To pass the assignment you must achieve a grade of 40% or above. Assignment Task Scenario For this coursework, you are required to select a real-world problem of your choice and apply various machine learning algorithms and methods to solve the selected problem. This problem could be a classification, regression, or clustering problem. Task 1 Your first task comprises the following: 1. Select a real-world problem. 2. Select suitable dataset(s) for the chosen problem. You can combine more than one dataset. 3. Analyse the dataset and pre-process it 4. Select more than one (at least three) appropriate Machine Learning algorithm for implementing the models. 5. Tune the models to achieve better performance. 6. Critically evaluate the results from applying the selected models on the chosen dataset. Note: · You are advised to choose a dataset that allows you to demonstrate your ability to perform. data analysis and pre-processing techniques such as, but not limited to, handling missing, categorical, non-numeric and duplicate values; outliers; scaling; etc. The selected dataset must contain at least 2500 samples, after pre-processing. The dataset cannot be one of the scikit-learn or synthetic datasets. Also, the dataset cannot be picked from www.kaggle.com. · If you are not sure where to start, you may find a list of suggested resources with numerous problems and datasets in the “Open Data Repositories” section on Aula. · You can use existing machine learning algorithms or a combination of some of them or even come up with a new algorithm of your own. · The required programming language is Python 3 (others are not accepted). Task 2 For the second task, you are required to submit a demonstration video recording the execution and performance of your implementation. Note: · The maximum length of the demonstration video is five minutes. · You are NOT required to walk through every line of the source code, but it is important to demonstrate the execution of all stages and the corresponding outputs of the source code. · Voice over the video must be used to describe what is happening and some of the reasoning throughout the video. · Ensure that all texts, tables, graphs, etc. are of an appropriate size to view, free from noise and not blurred. Also, ensure that the audio is clear. · You are required to use either Jupyter Notebook on a browser, Colab Notebook on a browser, Spyder or Visual Studio Code when recording the demonstration video. Task 3 Write a report (2500 words) based on a literature review and the technical work. This should include: Task 3a 1. A literature review on the application of machine learning to one of the following tasks: product recommendation, facial recognition, language translation, or text/image/video generation. Task 3b: This is a write-up of the work done in Task 1 1. A specification of the chosen problem area. 2. Comparing the approaches and results of other existing pieces of work on the same problem 3. Analysing and pre-processing the data. 4. Applying different algorithms and methods to build learning models. 5. Making appropriate adjustments to improve the models’ performances. 6. Critically evaluating the performance of the models. Note: · The first part of your report should review literature on the application of machine learning to one of the following tasks: product recommendation, facial recognition, language translation, or text/image/video generation. This task will be different from the problem area you are working on. · The second part of your report should focus on how algorithms/methods/techniques are actually applied or developments that are novel and specific to your work rather than how they work theoretically. · Your report should include appropriate outcomes such as data analysis diagrams, outcomes from the models, code snippets, etc. to support your text. Include the source of your dataset. · Include all your source code as text in Appendix B at the end of the report. Do not use screenshots of your code in Appendix B. Your code muse be presented as text (see coursework template). · Ensure you use comments to demonstrate an understanding of all parts of your code. · A course work template is provided as a guide in the “Assessment” section on Aula · The word limit includes quotations, but excludes the (GitHub, datasets, OneDrive) URLs, bibliography, reference list, and appendices (see coursework template) AI Use Policy (Amber Category): Students are permitted to use AI as an assistive tool under the following conditions: Citing AI Contributions: Students must identify and cite any portions of their work generated or assisted by AI. Submission Instructions: The submission of your coursework must be in the form. of ONE MS Word, or pdf, file through the indicated Aula submission link. Other formats (other than MS Word or pdf) will not be accepted. The submission of the implementation and demonstration video must be in the form. of: · A URL of Coventry GitHub Repository, OR · A URL of Coventry OneDrive shared folder The URL must be included at the beginning of your report (submitted on Aula). **Examiners will not check for the required URLs in other places. The shared folder or repository must be accessible by examiners, and should include the following: · The URL to the selected dataset(s) in README or a separate file. · The dataset(s) that are used for your problem. · The source code with appropriate comments, and · The demonstration video. Note: · No other platform. is accepted. Please ensure that it is COVENTRY GitHub or COVENTRY OneDrive. · Make sure that you add [email protected], [email protected] and [email protected] as Collaborators to facilitate marking · The submitted source code must be in the form. of a (Jupyter) notebook (.ipynb) · You must ensure that you commit your work appropriately (with the corresponding outputs of all cells – if applicable – clearly present) · Only include the notebook for your final submission (i.e., remove all draft notebooks) · The following naming convention must be used for your repository or shared folder: StudentID-Initials-s1 For example, a student Stanley Bassey whose student ID is 12345678 would name their repository or shared folder as 12345678-SB-s1 · A failure to use this naming convention may delay the release of marks and feedback for your coursework. Marking and Feedback How will my assignment be marked? Your assignment will be marked by the module team. How will I receive my grades and feedback? Provisional marks will be released once all submissions, including extensions, have been marked and internally moderated. Feedback will be provided by the module team on Aula alongside the release of grades. Your provisional marks and feedback should be available within 2 weeks (10 working days) after the extended deadline. What will I be marked against? Details of the marking criteria for this task can be found at the bottom of this assignment brief. Assessed Module Learning Outcomes The Learning Outcomes for this module align to the marking criteria which can be found at the end of this brief. Ensure you understand the marking criteria to ensure successful achievement of the assessment task. The following module learning outcomes are assessed in this task: 1. Compare supervised or unsupervised approaches to machine learning problems. 2. Select, apply and justify different pre-processing methods for a given dataset. 3. Select, apply and compare appropriate machine learning algorithms, techniques and methods to create and optimise different learning models for machine learning problems. 4. Communicate and critically evaluate the results from applying machine learning models, and recommend the most appropriate models for a given task.
Policy Memo Uncertainties over the new Greater Bay Area development plan’s impact on innovation and technology development in Hong Kong Topic: Advise the Hong Kong Innovation, Technology and Industry Bureau on policy alternatives and paths to reduce uncertainties around the GBA project and maximise its positive impacts on Hong Kong. You have two options for your policy memo: - Advise on Alternative Policies: Identify key challenges and propose overlooked policy alternatives that could enhance the GBA project's impact on Hong Kong's innovation and technology sector. - Analyse Existing/Proposed Measures: Provide a detailed analysis of the effectiveness and execution of existing or proposed measures related to the GBA project. You can target just one or two specific areas identified in your background section. In this case you can skip the policy alternatives section and provide your final recommendation. Briefing: Brief_Memo-3_GBA_Hong_Kong.pdf **Recent policy developments are crucial for your analysis. Refer to the latest documents and make sure you are up to date with the latest initiatives, such as technological collaborations, recent policy address, financial incentives for tech startups, or new cross-border digital infrastructure projects within the GBA.** Format: Your policy memo should be between 750-850 words in length. Use clear, concise language appropriate for the Chief Executive of Hong Kong and the Legislative Council. Include proper citations and a bibliography (not included in the word count). Incorporate relevant examples and case studies from the briefing and other sources Basic Memo structure consists of the following sections: Background/problem definition Issue analysis Policy options (with pros and cons) Strategic recommendations Additional work Limitations: 1. Header (to, from, date, subject) 2. Executive summary (~100 words) 3. Background and Issue analysis (~150 words) 4. Policy options (with pros and cons) (~200 words) 5. Strategic recommendations (~150 words) 6. Limitations and barriers (~100 words) 7. Conclusion (~100 words) Keep in mind: - Policy Memo serves as a concise analysis of the issue with brief recommendations of what policy actions should (or should not) be taken for the desired outcome - Conduct additional research on the topic to support your analysis and recommendations. - Please, propose specific, actionable, and evidence-based policy recommendations to address the identified challenges and capitalise on the identified opportunities. - It is valuable to see that you accompany your analysis and recommendations with relevant evidence, such as data, grapgics, links, references, etc. - The language of the memo should be professional but approachable as it targets practitioners, not academics. Therefore, if you use specific public policy terms, concepts, or frameworks, you have to make sure that your audience does not have to look them up or read additional materials in order to understand what your Memo is trying to convey. Memo rubric: Specifically, your memo will be graded in the following five aspects: 1. Clarity of writing -with appropiate language and grammar, so that the readears can follow your argument-. 2. Persuasiveness in argumentation. 3. Analytical rigor -clearly presented options, recommendations, and limitations, well supported arguments by the use e of evidence and comprehensiveness-. 4. Demonstration of understanding of relevant materials (concepts, theories, and tools) covered in the class. 5. Proper references and citations Resources for writing memos: Memo Guide Material
CHEMICAL ENGINEERING ASSESSMENT BRIEF 2025-26 Core Information Module code/title CENG0010 - Separation Processes I Due date 05 December 2025 Submission time 8:59am (term-time) Word/page limit 10 pages Footnotes, appendices, tables, figures, diagrams, charts, computer codes included in/excluded from word/page limit? Appendices (no more than 4 pages) Bibliographies, reference lists included in/excluded from word/page limit? Excluded Penalty for exceeding word/page limit? If your submission exceeds the specified word or page limit, a penalty of 10 percentage points will be applied to your total mark (i.e. If the maximum mark is 100, your score will be reduced by 10 points). The penalty will not lower your mark below the pass mark. If your coursework is both over-length and submitted late, the greater of the two penalties will apply. Penalty for late submission Standard UCL penalties will apply, please refer to:Deadlines & Late Submissions Artificial Intelligence (AI) category Category 1 - Not permitted for work submitted, revision only If AI can be used in assistive role, which specific use if permitted? N/A Submitting your assessment Assessment and Feedback tab, under Submission Points heading Anonymity of identity. Normally, all submissions are anonymous unless the nature of the submission is such that anonymity is not appropriate, e.g. presentations. Anonymity is required, use candidate number in filename CENG0010 SEPARATION PROCESSES I Project A mixture of methanol and propanol is to be separated in a tray distillation column. You are required to provide a report detailing the preliminary design of a distillation column that can meet the specifications given below. Please note that emphasis will be placed on the presentation of your report with a max page limit 10 pages. Any Aspen printouts included are to be placed in appendix at the end of the report and not in the main report. The final Aspen input file must also be submitted in a separate submission link on Moodle. Specifications: Specification Value Feed flow rate (kmol/h) 250 Feed composition (mol fraction methanol) 0.30 Feed temperature (oC) 25 Feed pressure (atm) 1.5 Minimum distillate composition (mol fraction methanol) 0.98 Maximum bottoms composition (mol fraction methanol) 0.02 Part A: Distillation [50 marks] Q1. Hand-calculations (Equations with worked-out solution and explanation) a) Use the Fenske-Underwood-Gilliland (FUG) method and the constant average relative volatility from data given in Table 1 to find the number of theoretical stages, N, as well as the feed point location, NF, using Kirkbride’s method, which is required to separate the mixture in a tray column assuming a total condenser and a kettle reboiler, using R/Rmin = 1.4 and operating pressure of 1.5 atm. Briefly comment on the assumptions employed and the accuracy of your calculations for the design of this column. (Calculation hint: Note that FUG equations for binary systems can be found in reference textbooks, e.g. Coulson & Richardson, Vol 2 [1]. Quote the literature sources foryour equations (not lecture notes). [20] Q2. Computer aided design using AspenPlus b) Using Aspen and shortcut calculations (DSTWU Model), find the number of theoretical stages N for the given specifications. Comment on the column pressure and inlet temperature and how it affects the performance of separation. Present the column design estimates in the main report, i.e. your FUG hand-calculations and the corresponding set of results obtained using Aspen, in a tabulated form. for Nmin, N, NF, Rmin and R. Compare the estimates and briefly discuss the reasons for any differences on the design between hand calculations and simulation. [10] c) Repeat your simulation with a more rigorous column model (RadFrac) with the estimates of N, NF and R found from the shortcut model (DSTWU), using the experimentally found tray efficiency from your distillation experiments. Comment on how the design results change and why. If your design specification is not met, provide a suitable alternative design that meets them. Compare the predicted separation performance between the two Aspen methods (not the hand calculations) and again briefly discuss the differences on the design results. [20] Table 1 Isobaric VLE data for the binary system methanol – propanol from experiments (P=1 atm) Part B: Absorption [25 marks] A gas stream consists of 95 mol% N2 and 5 mol% CO2. The CO2 is to be removed in an absorption column operated at 10 bar and 5 oC using pure water as the absorbent, and 95% of the CO2 is to be absorbed. Because of internal cooling coils, the operation can be assumed to be isothermal. The Henry’s coefficient of CO2 in water at the operating conditions is 800 bar. a) Determine the equilibrium coefficient K in the equation below based on the data given y* = K x where y* and x are mole fractions of CO2 in vapour and liquid at equilibrium, respectively. In the following, assume that mole ratio can be used instead of mole fractions, i.e. K remains the same in Y* = K X where Y* and X are mole ratios of CO2 in vapour and liquid at equilibrium, respectively. Find the required solute free solvent flow rate L, when L = 1.2 Lmin where Lmin is the minimum solute free solvent flow rate, as well as the outlet concentration of CO2 in water (as mole fraction). [10] b) Above it was assumed that the equilibrium conditions were linear, i.e. K remained the same for mole ratios as for mole fractions. Figure B1 gives the equilibrium diagram for CO2 in water for linear conditions and for actual conditions that shows that this assumption is incorrect. Discuss briefly what impact this assumption is likely to have had on your results. [5] c) In the laboratory experiment, you investigated the pressure drop and flow rate characteristics of packed columns by varying air and water loading. How did the pressure drop (ΔP) change with increasing air flow rate (Q) during the experiment? How did you identify the loading and flooding points in the packed columns? How do the loading and flooding points affect the performance of packed columns? [10] Figure B1. Equilibrium data for CO2 in water at 10 bar. Part C: Liquid-liquid extraction [25 marks] A feed of 10 kg min-1 of a 1 wt% mixture of acetic acid in water is to be extracted with pure benzene at 1 atm and 25 oC in a counter-current extraction column. The maximum amount permissible in the outlet water is 0.1 wt% acetic acid. A schematic of the column is given in Fig. C1, the equilibrium information for extraction in Figure C2 and relevant data are given in Table 2 and Table 3. a) Set up the material balance for acetic acid over the column. List all your assumptions clearly. A solvent feed stream of 400 kg min-1 has been proposed. What will the concentration of acetic acid be in the outlet solvent stream if this quantity of solvent is used? [7] b) With the solvent flow rate of 400 kg min-1 , a further suggestion is to operate the separation in an existing extraction column consisting of 4 theoretical separation stages. Would you recommend the use of this column and this solvent flow rate? Explain your answer briefly. [7] c) It has been suggested to operate the separation at a different temperature. Do you agree with this suggestion, and if yes, what temperature would you recommend? Explain your answer briefly. [4] d) In the laboratory experiment you extracted ethanol from an oil mixture that had 10% ethanol (by weight) using water as solvent. What challenges were associated with using oil in this experiment? Are there any sustainability, ethical or safety considerations in selecting these materials? [7] Table 2. Densities at 1 atm and 25 0C. Component Density [g cm-3] Acetic acid 1050 Water 876 Benzene 997 1-Butanol 810 Table 3. Distribution coefficients for immiscible extraction. Solute (A) Carrier (B) Solvent (C) Temperature [oC] Distribution coefficient Acetic acid Water Benzene 25 0.0328 Acetic acid Water Benzene 30 0.0984 Acetic acid Water Benzene 40 0.1022 Acetic acid Water Benzene 50 0.0588 Acetic acid Water Benzene 60 0.0637 Acetic acid Water 1-Butanol 26.7 1.613 Figure C1. Schematic of the extraction column. Figure C2. Equilibrium line for acetic acid (A) in water (B) with benzene (C) as solvent. References: 1. Coulson, J.M. and J.F. Richardson, Chemical Engineering, Butterworth Heinemann, Vol. 2, 5th ed., 2002.
CHEMICAL ENGINEERING ASSESSMENT BRIEF 2025-26 Core Information Module code/title CENG0013 Process Design Principles Due date 28 November 2025 Submission time 8:59am (term-time) Word/page limit 20 pages Footnotes, appendices, tables, figures, diagrams, charts, computer codes included in/excluded from word/page limit? Tables, figures, diagrams and charts are included in the page limit. Bibliographies, reference lists included in/excluded from word/page limit? Bibliographies and reference lists are excluded from the page limit. Penalty for exceeding word/page limit? Submissions above the word /page limit: the content that is over the limit will not be marked and 5 percentage points will be deducted (i.e. mark reduced by 5 marks for an assignment with a maximum mark of 100). The penalty will not take the mark below the pass mark. In the case of coursework that is submitted over-length and is also late, the greater of any penalties must apply and the content that is over the limit will still not be marked. Penalty for late submission Standard UCL penalties will apply, please refer to:Deadlines & Late Submissions Artificial Intelligence (AI) category Category 2 - Assistive If AI can be used in assistive role, which specific use if permitted? Proofreading Submitting your assessment Assessment and Feedback tab, under Submission Points heading Anonymity of identity. Normally, all submissions are anonymous unless the nature of the submission is such that anonymity is not appropriate, e.g. presentations. Anonymity is required, use candidate number in filename CENG0013 Design Project Design of a process for the production of ethylbenzene 1. The Process The majority of ethylbenzene (EB) processes produce EB for internal consumption within a coupled process that produces styrene monomer. We wish to design the process for the production of ethylbenzene. The production of EB takes place via the direct addition reaction between ethylene and benzene: C6H6 + C2H4 −−→ C6H5C2H5 . (R1a) The reaction between EB and ethylene to produce diethylbenzene (DEB) also takes place: C6H5C2H5 + C2H4 −−→ C6H4(C2H5)2 . (R1b) The competition between these two reactions limits the selectivity towards the desired EB prod-uct. The chemists have done a number of experiments in their lab. Using their data, they have come up with models for the single pass conversion of benzene, x, and the selectivity of EB to DEB production, S, as functions of the residence time, t, in seconds: for t ∈ [5, 1000] s in both cases and ρ ∈ [1, 8] is the molar ratio of benzene to ethylene fed to the reactor. The chemists have determined that the ratio, ρ, has a significant effect on the selectivity. Reaction R1a is an exothermic reaction. Therefore, the reaction takes place in the vapour phase. Since the moles of reactants are more than the moles of products, any reactor used will need to be run at high pressure (20 bar), according to Le Chatelier’s principle. The usually adopted temperature range for this reaction is T ∈ [350, 440] ◦C. 2. The design task The process needs to be designed to meet a production requirement of (20+ d/10) mol s-1 of ethyl-benzene with molar purity 0.98. d is the last digit of your student ID number. Please state the value of d at the start of your submission. This ethylbenzene will be subsequently fed into a process (not considered here) for the production of styrene. To meet this requirement, separate feeds of benzene and ethylene are available. Both of the feed streams are available at T = 25 ◦C and P = 20 bar. The benzene feed has a 2% by mole impurity of toluene (C6H5CH3 ). The chemists have deter-mined that this small amount of toluene also reacts with ethylene: C6H5CH3 + 2 C2H4 −−→ C6H5C2H5 + C3H6 (R1c) The toluene reacts completely in a few seconds (t < 5 s). The design of the process flowsheet will be based on the application of the full Douglas approach, levels 1 through 5. You will be expected to identify and to model all the main processing units, along with sizing information, and their interconnections including possible heat exchanges. 3. Market information and cost models The accountants have given you a detailed report of the market prices of reactants and products as well as models for estimating processing unit costs. Table 1 summarises the costs or values for particular streams. Table 2 presents the cost models for various types of units. The costs of the different utilities available, for heating, cooling, and electricity, are given in Table 3. Table 1: Market prices for feeds and products. Table 2: Cost models for processing units for estimating the total annualised cost, TAC, in mil-lions of €, of buying, installing, and maintaining the equipment. Table 3: Cost data for utilities. 4. Things to do Given the chemistry, the process requirements and the cost data and models above, develop a full process flowsheet for the production of ethylbenzene by following these steps. In attempting each of the following steps, fully itemise and justify all decisions taken. Marks allocated to each step are indicated in the right margin for a total of 100. 1. Apply levels 1 through 4 of the Douglas approach so as to develop a process flowsheet consisting of the main process units. In your report, summarise the key decisions you took, including the identification of design variables, with justification for these decisions. There is no need to include any discussion of elements of the Douglas hierarchy that do not apply to your case. Do not perform. any economic potential analysis at this point. Sketch the process structure obtained after applying all 4 levels of the hierarchy, labelling all input, output, and recycle streams; diagrams for each of levels 1-3 are not required. [20] 2. Implement a process and cost model based on the process identified in the previous step. Use one of GAMS (recommended), MATLAB, gPROMS, or a spreadsheet calculator (not recommended). The model should include costing information sufficient to calculate the economic potential for the process design obtained after level 4. Details on how to model the various potential processing units are given in the Appendices below. The model should be fully commented and must be included as an Appendix in your report, as text and not as a screenshot, and must also be submitted as a separate file in its native format to allow us to run your model. [20] 3. For the final flowsheet obtained with level 4 of the Douglas approach, use your model to investigate the behaviour of the economic potential in terms of the chosen design variable(s), considering annual hours of operation as indicated in the lecture notes for the type of process operation expected (level 1 of the Douglas hierarchy). Discuss how the design variables and the decisions you made in levels 1 to 4 impact on the economic potential. Plots of the economic potential with respect to the design variables will be required to support your discussion. [10] 4. Prepare a full stream table for the final process design from level 4 for your choice of design variable value(s). Fully justify your choice of values for the design variable(s) for this stream table. [5] 5. Use Aspen Plus to simulate the process identified in the first step. Use this simulation to a) fill in a stream table for the process and b) determine the heating and cooling duties of all of the units. Discuss the possible reasons for and any implications of the differences you may observe between the stream tables from the previous step (step 4) and this step. If you were unable to prepare a stream table for either of the steps, discuss what you may have expected to see when comparing the stream tables. In your report, include a screenshot of the process flow diagram in Aspen and a screenshot of the stream table. The Aspen model must also be submitted as a separate file in Moodle. [10] 6. Applythe Pinch method, directly yourself as taught in the lectures and tutorial sessions, to design and cost a heat exchanger network for the process using the heating and cooling duties determined by the simulation. Should any reactors not be adiabatic and require either heating or cooling, the inlet and outlet temperatures for heat exchange should be considered to be ±5 ◦C around the operating temperature of the reactor. Use ∆Tmin = 20◦C for the pinch analysis and U = 1.5 kW m-2 ◦C-1 for the overall heat transfer coefficient for the design of any exchanger in the network. Discuss the economic implications of the heat exchanger network on your previous conclusions in step 3 regarding the economic potential of the process. [30] Note: Please see Appendix A for alternative heating and cooling loads in the case that you find that you are unable to answer question 5. However, if you were able to generate heating and cooling loads in Aspen, you must use those values. 7. Which decisions taken in levels 1 to 4 of the Douglas hierarchy had the most impact on the final design and why? Draw alternative process diagram(s) to illustrate your reasoning. [5] 5. Submission The submission, via Moodle, will consist of three parts: 1. A report which answers the above questions, written using a word processor and submitted as a PDF document. This report must include your model (step 2) as an appendix in the form. of text (not screenshots) and also two screenshots of your Aspen simulation, one showing the full process flow diagram and one for the stream table. If you have used a spreadsheet calculator for the modelling in step 2, please insert two screenshots of the spreadsheet, one with values and one showing the equations, in the report as the appendix. 2. The model for level 4 from step 2, in your chosen modelling language, including the economic potential calculations for that level. The model should be submitted in the form. of the original file (e.g. as a .gms file for a GAMS model); a text version of the model must also be included in the report as an appendix, as noted above. 3. Your Aspen Plus simulation model should be included in the form. that Aspen can read. Also include, as noted above, screenshots of Aspen showing your process flow diagram and a screenshot of the stream table within your report. Please note that parts 2 and 3 must be submitted as original files (e.g. .gms for a GAMS model) and not a PDF document. We must be able to load your model into the appropriate software to verify that it works. All work must be your own and you must not discuss the project with anybody else. You may use the various tutorials to discuss doubts with others in your class. The report should be a maximum of 20 pages. The content that is over the limit will not be marked and 5 percentage points will be deducted. The penalty will not take the mark below the pass mark. Assistive use of AI is permitted.
For the final paper assignment, each student will submit one paper. Although your group has the same design and final prototype, your individual paper can still reflect on your writing, your research, your critical reflection of the existing research, the market, and lessons learned during the design process. The paper will also need an introduction and a discussion/conclusion section. The final paper is due 11:59pm on December 5, 2025. The whole paper will be 10 pages long (double-spaced, using Times New Roman, 12 font size), plus at least 10 references, any additional tables, or figures. Your paper must conform. to the requirements of the American Psychological Association (APA) style. Page requirement (10 pages) does NOT include references, tables, and figures. Provide a thorough description of your persuasive technology developed by your group, with the following sections: Introduction Statement of the problem/need. a.What problem do you aim to address? (e.g., lack of physical activity, poor sleep, mental health, misinformation). Statement of the goal/aim of the proposed technology. a.What is your proposed persuasive technology? b.What are the goals of persuasion? What aspects of the users can be changed by using the mobile app? c.What are the main functions of the technology? How would they address the problem/need? (e.g., a chatbot that can provide sleep advice and track sleep patterns; the goals are to change users’ knowledge and beliefs about sleep, help users understand their behaviors, and motivate them to make behavior. changes to improve sleep) A brief analysis of your target market. a.Who are your target users? b.What are the realistic user scenarios? Literature review/Theory A brief analysis of existing technologies. a. Are there existing technologies? What do they do? b.How is your proposed technology different from the previous ones? Statement of theoretical bases for your technology. a.How can your technology achieve your goals? b.Are there theoretical bases for why the various functions can change beliefs, attitudes, and/or behaviors? Design Description of PT design development.a.Describe your proposed persuasive technology. b.Describe the main functions of the technology. How were they implemented in the design?c.What was the process of developing the technology prototype? Discussion/Conclusion What are the next iterations of this technology and what are your revision/development plans? What are your major roles in this project and what have your learned from doing this project?
CCC8013 The Process of Science Research Report Intended learning outcomes (ILOs) 1. Discuss the foundations of knowledge and inquiry about science, and how science has influenced society. 2. Apply intellectual and practical skills (inquiry and analysis, critical thinking, written communication, quantitative/data literacy, and information literacy) across a range of scientific contexts. 3. Demonstrate the ability to integrate and apply learning about the process of science to new settings and complex problems. 4. Develop personal and social responsibility (global civic knowledge and engagement, intercultural competence, and ethical reasoning foundations) focused on real-world challenges. 5. Demonstrate the motivation and ability for life-long learning about science-related issues. Submission guidelines • Use the “Template for Written Assignments” document (available on Moodle) as your cover page • The word limit is 1,500-2,500 words (not including references, tables, and figures), following the standard scientific report conventions (see Format of Research Report.pdf). • Use Times New Roman font, font size 12 with single spacing. • In-text citation and a reference section are required. • A title is required, but a title page is NOT required. • The total number of figures and tables should be 3~5. • At least 5 academic references are required. • Submit your report in a Microsoft Word (.doc or .docx format) or PDF file via Turnitin (on Moodle) by 02-Dec-2025, 23:59 • Late submissions will be penalized based on the rules listed out in the document “CCC8013 Important Things” Grading of assignment This assignment towards 30% of your final grade for the course. See the last page of this document for the detailed breakdown of how this assignment will be graded. Instructions for assignment Your job in this assignment is to: • Choose any SDG topics (http://sdgs.un.org/goals). • Describe how your data is collected (e.g., if you choose to use second-hand data, please describe which databases did you use, and how did you combine different datasets into a new one for your research. If you choose to use questionnaires to collect data, please explain which types of questions (like multiple-choice or rating scales) did you use, and how many participants you included). Mention any specific conditions, such as the setting of the survey or the time frame for responses. For example, if you surveyed students about their study habits, explain why you chose that group. Provide enough detail so others can replicate your study. • Present your findings using tables and figures with detailed captions. Summarize results briefly in the text, referring to figures parenthetically, and use subheadings for clarity. • Develop your discussion around your own data, compare it with findings from the literature, specify which Sustainable Development Goal (SDG) your work supports, and outline actions to promote this SDG at both the individual and community levels.Any supplementary information (e.g., raw data, questionnaire) can be included in the appendix. • Include a reference list (i.e. bibliography) for all your sources, and include in-text citations. The reference list will NOT be counted towards the word limit. Citation format: You may use any commonly accepted citation format (e.g., APA, MLA, Chicago, Harvard…etc.) [see below] • Be careful not to plagiarize! Never copy and paste! Paraphrase instead [see below] Guidelines for references/citations A reference list (or bibliography) 1) credits authors whose work you referred to, and 2) helps readers locate your information sources. As a minimum, references must include: • Journal articles: Author names, year of publication, title, journal name, journal volume, page range • Books: Author names, year, title, publisher • Websites: Author names, year of publication, article title, website name, URL, date of access • Examples of “Biological Conservation”journal: Reference to a journal publication: Van der Geer, J., Hanraads, J.A.J., Lupton, R.A., 2010. The art of writing a scientific article. J. Sci. Commun. 163, 51–59. Reference to a journal publication with an article number: Van der Geer, J., Hanraads, J.A.J., Lupton, R.A., 2018. The art of writing a scientific article. Heliyon. 19, e00205. Reference to a book: Strunk Jr., W., White, E.B., 2000. The Elements of Style, fourth ed. Longman, New York. Reference to a chapter in an edited book: Mettam, G.R., Adams, L.B., 2009. How to prepare an electronic version of your article, in: Jones, B.S., Smith , R.Z. (Eds.), Introduction to the Electronic Age. E-Publishing Inc., New York, pp. 281–304. Reference to a website: Cancer Research UK, 1975. Cancer statistics reports for the UK. http://www.cancerresearchuk.org/aboutcancer/statistics/cancerstatsreport/ (accessed 13 March 2003). Reference to a dataset: [dataset] Oguro, M., Imahiro, S., Saito, S., Nakashizuka, T., 2015. Mortality data for Japanese oak wilt disease and surrounding forest compositions. Mendeley Data, v1. Reference to software: Coon, E., Berndt, M., Jan, A., Svyatsky, D., Atchley, A., Kikinzon, E., Harp, D., Manzini, G., Shelef, E., Lipnikov, K., Garimella, R., Xu, C., Moulton, D., Karra, S., Painter, S., Jafarov, E., & Molins, S., 2020. Advanced Terrestrial Simulator (ATS) v0.88 (Version 0.88). Zenodo. In addition to your reference list, in-text citations are required. • In-text citations = a short version of a reference, but located within your main text • Typical format: (author’s last name, year of publication) • Examples: … Fishes are one of the most diverse groups of animals, making up a quarter to half of all vertebrate species globally (Stiassny, 1996) … Two authors: (Chan & Ng, 1996); >2 authors: (Halloran et al., 1996) Check out the citation guidelines provided by our library. Any citation style (e.g., APA, MLA, Harvard) is acceptable, but please use only one style. throughout your paper. Plagiarism (IMPORTANT) Plagiarism = presenting someone else’s work or ideas as your own, whether intentionally or unintentionally. Plagiarism is considered intellectual dishonesty (i.e., cheating) and comes with grave consequences. See “IMPORTANT: Avoid Plagiarism” document on course Moodle page. Also, check out the Lingnan University guide on ways to avoid plagiarism. Plagiarism can happen when: • Copying and pasting text from sources • Using information without crediting the source • Using direct quotations excessively (even with proper citations) To avoid plagiarism: • Always paraphrase (= rewrite using your own words) Paraphrasing DOES NOT mean copying and pasting, and inserting a few extra words More information about paraphrase is available on the “CCC8013 Process of Science - ENGLISH SUPPORT” Moodle page • Always cite your sources (in-text and reference list) • Avoid using direct quotations unless necessary. Use quotations marks (“ ”) for quotes. Turnitin is a plagiarism-detection software. Your assignment will be compared against the whole internet and other student submissions (past and present), and a similarity score will be calculated. If the similarity of your assignment exceeds the critical threshold of 20%, excluding properly referenced material, it will undergo a thorough plagiarism assessment process. In such case, you may get zero marks and be referred to the university for further disciplinary action (e.g., automatic failure for the course). Grading Rubric of Independent Research Report (total of 30 marks) FORMAT (up to 10 %): Follows formal scientific report conventions, which includes Title, Abstract, Introduction, Methodology, Results, Discussion, Conclusion, References (see Format of Research report.docx). CONTENT (up to 80%): • Title: concisely presents the content of the report. • Abstract: summarizes the major aspects of the entire report. o The question investigated. o The experimental design. o The major results. o A brief summary of conclusions. • Introduction: reviews the available studies on this topic and states the problem investigated, methods employed and major conclusion achieved. o Background and motivation. (Why choosing this topic, why is it important) o Literature review. (What has been done on this topic, what are the remaining issues) o Research question. (What problems are you going to handle through this research) • Methodology: describes extensively how the data were collected/chosen. o A brief description of the method or plan. o Technical details (Repeatability and reasonability). o In case you have no clue on the “what I can do"part, you may use design thinking as a tool. However, ifyou have no problem figuring out the "what I can do"part, there is no need to use design thinking. • Results and discussion: present the data in a logical order and provides Data, Tables and Figures. Discusses topic thoroughly and objectively. (Results and Discussions can be combined or written separately.) o Figure: You should plot your own graphs from the raw data. Graph generated automatically by online tools (e.g. Google Forms) or webpages (e.g. Statista) are not entertained. o Explain the results with figures/descriptive statistics. o Analyze the results. (Which pieces of evidence (supported by data) suggest that the proposed solution will be able to handle the question we raised in the introduction?) o Compare with existing work. (What is the benefit of using our method, compared with the existing ones?) o Provide practical recommendations based on your findings, including suggestions for daily life. o Limitation & future research. • Conclusion: includes an effective summary of the major points based on the data. • References: are correctly cited in a consistent format. • Appendix (optional): is clearly and completely provided. STYLE/TONE (up to 5%): Uses precise, technical/professional language, is unified and coherent, varies sentence length and structure to keep reader’s attention, connects ideas effectively. GRAMMAR/SPELLING (up to 5%): Shows effective use of proof-reading and editing: Eliminates all but a few minor errors in grammar, spelling, punctuation, acronym usage, and capitalization.
Electronics and Electrical Engineering Power Systems / Electrical Energy Systems Laboratory Unloaded Three Phase Transformer 1. Objective The objective of this experiment is to study the effect of various transformer connections on the losses and harmonic content of the primary current and voltage waveforms in a three-phase transformer with no connected load. Operation of the transformer under overvoltage conditions will also be observed. 2. Introduction A large power system has a lot of relatively small transformers located close to the customers. These small transformers spend most of their working life (40–60 years) with minimal load and only a very small part of their working life operating close to full load. Consequently the light load losses of these smaller transformers have a huge economic significance to the power system operator. The power system operator must make a trade–off between the initial cost of a transformer and the lifetime financial cost of the losses in the transformer. Clearly the cheapest transformer to buy (using the least amount of material) is unlikely to have the lowest total lifetime cost of ownership. In this experiment we will study some of the factors that influence the no-load losses of a typical distribution transformer. Equipment 3-phase Power Supply (electronic) Potential Transformer (Two) 3-phase Transformer Current Transformer 3-phase Wattmeter Digital Storage Oscilloscope Digital Multimeter Leads 3-phase Power Supply The 3 phase power supply is an electronic source which can provide up to 42V line (24V phase) RMS. The “Output Waveform” has three different settings:- (a) “sine”: an ideal, balanced 3 phase sinusoidal supply, with no harmonics. (b) “unbal sine”: an unbalanced 3 phase supply with one phase reduced in amplitude (not used during this experiment). (c) “sine +3rd”: a balanced 3 phase supply with a significant amount of 3rd harmonic distortion. This supply can provide up to 1A continuously and up to 2A for a few minutes before it gets too hot. Take care when operating to make sure that the current supplied is not too great. Leave the green illuminated power switch ON to keep the internal fan running and turn the "Output" switch On and Off as required. If the power supply overheats you will need to leave it ("Output" set to "Off") for about 15 minutes with the fan running before it cools sufficiently to allow further use. 3-phase Wattmeter The 3 phase power meter has connections for power supply and load. Keep the neutral connection connected to the transformer star point to minimize measurement errors. This meter measures and displays RMS quantities. The default display shows line voltage, average line current, total power consumed and overall power factor. Pressing the red button will cycle the display through different measured values (individual phase voltage, currents and power are the most useful). Power is on page 1, Line Currents are on page 3. Note carefully the displayed units of measure. Transformer The transformer that you will be testing is a scale model of a mass-produced distribution transformer. The transformer is rated for a full load of approximately 200VA. Each phase has a primary with a tap changer and two independent secondary windings. The primary tap changer allows operation with -5%, NOM(nominal), or +5% primary turns. Note that because of the core geometry, this transformer is NOT perfectly balanced; the centre limb has two short flux paths and each outer limb has a long and a short flux path. In a power system each transformer of this type would be connected to the source differently so that the whole power system operates with a balanced load overall. Potential Transformers and Current Transformer In a large power system the voltages and currents used are too dangerous to attempt to measure directly. To reduce the system voltages and currents to a safe level for observation, potential and current transformers (also known as instrument transformers) are installed at strategic locations. In this experiment you will use the instrument transformers to observe the power transformer voltage and current waveforms on an oscilloscope. Note the scaling factor printed on each transformer box. The current transformer connects with a jack plug to the circuit being observed. The jack socket contains a switch to break the circuit and put the current transformer primary in series with the circuit. The no–load current waveform. of an over–excited transformer will contain significant harmonic distortion, mainly third,fifth, and seventh harmonics. This can be explained in terms of magnetic saturation and hysteresis. On the one hand, a sinusoidal induced emf at fundamental frequency requires a similar sinusoidal variation of flux, which in turn requires a non–sinusoidal magnetizing current. On the other hand, a sinusoidal magnetizing current produces non–sinusoidal flux and a corresponding non–sinusoidal emf. In a balanced, three–phase circuit, third harmonic components are co–phasal. Accordingly, third harmonic currents do not add up to zero at the star point and a star– neutral connection provides a return path for 3rd harmonic currents. Preliminary exercise: Sketch the fundamental sine waves of the three-phases, 120 degrees apart, and their third harmonic components on the same axis on graph paper in your laboratory book. This will show that the third harmonic components are co- phasal. 3. Procedure Measurements During the experiment, the transformer will be connected in different ways and under different conditions. For each setup (described in the following pages), record each of the measurements in the list below. Set "Output" to "On" before taking measurements, and to "Off" when finished; try to minimise the amount of time that it is "On". Using the Digital Multimeter:- Primary Line Voltage "VRY" Secondary No. 2 Line Voltage ("Vry" for Star-Star ; "Vr1r2" for Star-Delta) Primary Phase Voltage "VRN" Secondary No. 2 Phase Voltage "Vrn" (not applicable for Star-Delta) Using the Wattmeter:- Primary Line Current "IR" Primary Line Current "IY" Primary Line Current "IB" Total Power consumed (i.e. Power Losses) Using the Potential Transformer and Digital Storage Oscilloscope:- Primary Line Voltage "VRY" Secondary No. 2 Line Voltage ("Vry" for Star-Star ; "Vr1r2" for Star-Delta) Phase-shift of Transformer ("VRY" to Sec2 "Vry" for Star-Star ; "VRY" to Sec2 "Vr1r2" for Star-Delta) Primary Phase Voltage "VRN" Secondary No. 2 Phase Voltage "Vrn" (Not applicable for Star-Delta) Using the Current Transformer and Digital Storage Oscilloscope:- Primary Neutral Current "IN" Current in Delta-Connected Secondary No. 2 (Extended Star-Delta only) Tabulate the results. Ensure Primary Voltage measurements are made directly at the Transformer Primary (For the "Extended Star" connections, the voltages should be higher than shown on the Wattmeter). Use the printer to plot any waveforms which have harmonic content : these will be required for discussion, later. Annotate the printouts so that you can identify them later. 3.1 Star-Star Connection Fig. 1 Star-Star Connection 1) 3-Phase Power Supply setup Set "Power" to "On" Set "Output Level" to "max" (42V Line Voltage) Set "Output Waveform" as requested, below. 2) Transformer connection and setup Before altering connections on the transformer, always ensure that the "Output" switch on the 3-phase Power Supply is set to "Off". Connect the three-phase transformer as shown in Fig. 1 (Secondary no. 2 is connected as a star). At this stage, ensure that the Neutral connection on the Power Supply is not connected to anything (i.e. floating star). Set Primary Tap Changer to "NOM". 3) Measurements / Observations For each case, below, take a full set of measurements (see page 3) Case 1: (Output Waveform "sine" ; Neutral wire NOT connected ; Tap NOM) Case 2: (Output Waveform "sine" ; Neutral wire connected ; Tap NOM) Case 3: (Output Waveform "sine +3rd" ; Neutral wire NOT connected ; Tap NOM) Case 4: (Output Waveform "sine +3rd" ; Neutral wire connected ; Tap NOM) 3.2 Extended Star-Star Connection Fig. 2 Extended Star-Star Connection 1) Connect the three-phase transformer as shown in Fig. 2. Set Primary Tap Changer to +5%. The primary winding and secondary winding no. 1 are connected in series, to make an extended star. This connects secondary no.1 in antiphase in series with the primary. The primary voltage will now be considerably higher than design normal and operates the transformer primary under overvoltage conditions. This connection setup would never be used in a real system; here we are using it to significantly increase the primary voltage beyond what the power supply is capable of to the point of seriously over–exciting the transformer. Secondary no. 2 is connected as a star and used for measurements. DO NOT leave the power supply and the transformer operating (i.e. "Output" set to "On") for more than a few seconds at a time when operating with this setup. The power supply is heavily loaded and will easily overheat. Use the trace storage facility on the oscilloscopes to ensure that the transformer is not being driven in this way for more than a short time. 2) Measurements / Observations Case 1: (Output Waveform "sine" ; Neutral wire NOT connected ; Tap +5%) (a) Take a full set of measurements (see page 3). (b) Observe the Primary Line Current “IR” waveform. while changing the Primary Tap Changer from +5% to NOM and -5%. Note any effect on harmonics and losses. Case 2: (Output Waveform "sine" ; Neutral wire connected ; Tap +5%) (a) Take a full set of measurements (see page 3). (b) Observe the Primary Line Current “IR”, and “Neutral Output Current” waveforms while changing the Primary Tap Changer from +5% to NOM and -5%. Note any effect on harmonics and losses. Case 3: (Output Waveform "sine+3rd" ; Neutral wire NOT connected ; Tap +5%) (a) Take a full set of measurements (see page 3). (b) Observe the Primary Line Current “IR”, waveform. while changing the Primary Tap Changer from +5% to NOM and -5%. Note any effect on harmonics and losses. Case 4: (Output Waveform "sine +3rd" ; Neutral wire connected ; Tap +5%) (a) Take a full set of measurements (see page 3). (b) Do NOT change the Primary Tap Changer to the other two positions because you will probably overload the power supply. What do you think would happen to the transformer under test if the Primary Tap Changer was set to the other two positions? 3.3 Extended Star-Delta Connection Fig. 3 Extended Star-Delta Connection 1) Connect the three-phase transformer as shown in Fig. 3. Set Primary Tap Changer to +5%. The primary winding and secondary winding no. 1 are connected in series—extended star. The secondary winding no. 2 is connected as a delta. Secondary no. 2 is used for measurements. As before, DO NOT leave the power supply and the transformer operating (i.e. "Output" set to "On") for more than a few seconds at a time. 2) Repeat Section 3.2.2. 4. Calculations Calculate the line-to-line voltage ratio for each of the three transformer connections. 5. Conclusions Discuss the presence or absence of harmonic components in the waveforms. Discuss the advantages and disadvantages ofthe various transformer connections. What connection method has the lowest no-load losses? What effect does the primary neutral connection have on losses? Standard practice in the UK for connecting distribution transformers is to use a delta connected primary and a star connected secondary. What are the advantages and disadvantages for this connection method if the connected load draws a non-sinusoidal current? (Consider triplen and non-triplen harmonics and losses).
Electronics and Electrical Engineering Power Systems / Electrical Energy Systems Laboratory The Long Transmission Line 1. Introduction Power transmission lines run for up to 1500 km in certain parts of the world where hydro-electric power stations are located far from city load centres. Lines longer than about 200 km need special “compensating” equipment to control the voltage along the line, and to ensure the stability of the power transmission. This is because the voltage along an uncompensated line deviates from the ideal “flat voltage profile”, depending on the load and the length of the line. 2. Objectives a. To demonstrate the Ferranti effect-voltage rise along a lightly-loaded transmission line; b. To demonstrate the flat voltage profile and linear phase-shift along a long transmission line loaded at its natural load or “surge -impedance load” (SIL); and c. To demonstrate the effect of line length. 3. Theory A transmission line can be represented approximately by a ladder network of LC branches as shown in Fig. 1. The inductance and capacitance are distributed along the line, but a ladder network with a large number of lumped elements can provide a fairly accurate model of the actual line. Note that the resistance of the cable is considered negligible: the electrical properties are dominated by the series inductance and shunt capacitance. Fig. 1 Lumped-parameter model of long transmission line The electrical properties of the line are dominated by two important parameters: the surge impedance and the electrical length. Surge impedance The surge impedance Z0 is given by Z (1) where Lis the total line inductance [H] and Cis the total line capacitance [F] (of course, in this case you could use ‘per-unit-length’ or ‘per-section’ values, due to cancellation in the formula). Even though Land Care basically reactive elements, Z0 is a real number: in other words, it has the properties of resistance. Electrical length The actual length of a transmission line is measured in km, but the electrical length θ is measured in radians and is given by (2) Note that here you must use the Land C values for the whole line. ω = 2πf is the radian frequency of the voltage and current (normally f = 50 or 60 Hz). A line for which θ = 2π is said to have a length of one wavelength at the operating frequency f, but such lines are impractical and θ rarely exceeds π/6 or 30° . Key properties When the receiving-end of a long line is open-circuited, the voltage profile along the line is given by where x is the distance from the sending end, a is the actual line length, and VS is the phasor voltage at the sending end. The voltage at the receiving end is given by setting x = a: thus This equation shows one problem with long lines: the receiving end voltage Vr exceeds the sending-end voltage VS by the factor 1/cos θ. For example if θ = 30°, Vr = VS / cos(30°) = 1.155 VS —an excess voltage of 15% over the nominal or rated value. This is too far outside the acceptable range of voltage. A line terminated in Z0 has a flat voltage profile, i.e. V (x) = VS = Vr . The power corresponding to this load impedance is the surge impedance load (SIL) or natural load. If the load is greater than SIL, the voltage profile tends to sag. If it is less, the voltage profile tends to rise. [At SIL the reactive power requirements at the ends of the line are zero. Below SIL, the line generates excess reactive power at both ends, but above SIL, it absorbs reactive power at both ends.] 4. Experiments The model transmission line has ten LC sections. In each section L = 7.29 mH and C = 0.020 µF. If the line is operated at 700 Hz, ω = 2π × 700 = 4398 rad / s . a. Use eqn. (1) to calculate the surge impedance Z0 in ohms. b. Use eqn. (2) to calculate the electrical length θ in degrees and radians. (Remember that Land Care for the whole line, not just one section). Connect the model transmission line as shown in Fig. 2. Ensure that the function generator is producing a sine wave, and that the 50 Ω output is the one connected. Keep channel 1 of the oscilloscope connected to the sending-end voltage, and use channel 2 as a roving connection. The DVM / Multimeter can also be connected anywhere along the line. Fig. 2 Connection of model transmission line. The ground wires to the oscilloscope and the DVM are not shown in full. c. Open-circuit test Set the frequency to 700 Hz.4 Set the output voltage to about 10 V pk-pk. Set both oscilloscope channels to 2 V/division. Set the DVM to AC volts, 20 V range. The DVM measures the RMS voltage, i.e. Vpp /2 × 1/ = 3.5 V approximately. Using the DVM, measure the voltage Vat each of the 10 points along the line and calculate the ratio V/ VS for each point. Plot a graph showing the variation of per-unitvoltage v = V/ VS along the line, i.e. v(x). Determine the ratio V/ VS and verify that it agrees with eqn. (4). Use the oscilloscope to measure the phase angle of the voltage relative to VS at the mid-point and at the receiving end. Use these phase angles together with the corresponding voltage values to draw a phasor diagram showing the relationship between VS, Vr and the mid-point voltage Vm d. Surge-impedance load test Connect a resistive load equal to the surge impedance load Z0 calculated at (a) above. Re-adjust the sending end voltage so that it has the same value as in experiment (c), or if you can't reach that voltage, as near to it as possible. Repeat all the measurements of test (c), including the phase angles ofthe voltages at the mid-point and the receiving end, relative to the sending end. Verify that the voltage profile is flat, and try to explain any deviations from true flatness. Compare the phase angle between VS and Vr with the electrical length of the line, and comment on the result. Also comment on the phase angle between VS and Vm and the phase angle between Vr and Vm e. Line loaded above the surge-impedance load Connect a resistive load of resistance equal to half the surge impedance load Z0 calculated in (a) above. Re-adjust the sending-end voltage so that it has the same value as in experiment (c), or if you can't reach that voltage, as near to it as possible. Repeat all the measurements of test (c), including the phase angles ofthe voltages at the mid-point and the receiving end, relative to the sending end. Comment on the voltage profile and the new values of the phase angles between VS and Vr, between VS and Vm and between Vr and Vm . How would you restore the receiving end voltage Vr to be equal to VS without changing the real power transmitted to the load?4 f. Open-circuit test on double-length line The line length can be doubled by connecting two model transmission lines in series. Alternatively, according to eqn. (2), we can simulate the same effect by doubling the frequency to 1.4 kHz. Do this, and repeat experiment (c). Comment on the differences between the single-length line and the double length line. How would you restore the receiving end voltage Vr to be equal to VS?
Electronics and Electrical Engineering Power Systems / Electrical Energy Systems Laboratory Synchronous Generator Operating Characteristics 1. Objectives 1) To conduct open-circuit and short-circuit tests on a three-phase synchronous generator. 2) To derive the synchronous reactance from results of the tests and to find out the per unit value. 3) To conduct load tests at one input power level to the machine operating as a synchronous generator in a large power system, and for three different field excitation levels to measure output current and power factor. 4) To construct, for the three conditions in the load tests, the phasor diagrams and, from these, to determine the rotor (load) angle and field excitation current and to compare these with measured values. 2. Introduction A synchronous machine cannot be directly connected to a power system and self- start. If this is attempted with a machine of any significant size, excess current will flow and damage to equipment is likely. When connecting a synchronous machine to a power system, the machine terminal voltage must match the system voltage (as a phasor quantity) before connection is attempted. Once the synchronous machine is connected to the power system, the operating conditions of the machine can be adjusted for the application (motor, generator). Note that the synchronous machine will always run at power system speed and the operating power factor can be controlled (within reason) by adjusting the field excitation current of the machine. If the synchronous machine starts to lose synchronism with the power system, excess current will flow and fuses/circuit breakers will operate, disconnecting the machine from the supply. On the bench the following equipment is provided - A synchronous motor/generator on a frame. coupled to a DC generator/motor with an optical shaft speed sensor. A variable DC power supply and associated Single- phase Wattmeter to drive the DC motor prime mover. A smaller variable DC power supply and an Ammeter (Digital Multimeter configured as Ammeter on 2A range) to set the synchronous machine field excitation current. A synchronising switch and a 3-phase Wattmeter to connect the power terminals of the synchronous machine to the power system. A red cased synchronous strobe light. This strobe light makes flashes of light synchronous to the mains power supply. The Synchronising Unit (similar to a Synchroscope) will probably be unfamiliar. The internal circuit is shown in Figure 1, below. In its simplest form (selector switch set to ‘intensity9) it consists of an indicator lamp connected across each contact of a 3-pole switch. If the synchronous machine and the supply do not have matched (phasor) voltages then the lamps will light. If the lamps are dark, then there is no voltage across the switch contact and it is safe to close the switch. A refinement of this setup (selector switch set to ‘rotation9) is to connect 2 of the 3 lamps on different phases across the switch. The lights will now illuminate in a slowly changing pattern showing whether the machine is running slow or fast compared to the power system. The machine and the power system are synchronised when the top lamp is dark and the two lower lamps are equally brightly illuminated. If the operation of the lamps at each selector switch position (Intensity, Rotation) is the opposite to that described above, this is because the 3-phase Power Supply and the Generator are "rotating" in opposite directions. To correct this, swap two of the connections (e.g. at U1 and V1 on the Synchronous Machine). Figure 1 – Internal circuit of Synchronising Unit 3. Experiments 3.1. Preliminary Actions 1) Make sure the “Load Switch” on the Synchronising Unit is Off! 2) Examine the synchronous generator and calculate the nominal Line current based on the nameplate voltage and power (in particular double check if the nameplate shows line or phase voltage value). Determine the number ofmagnetic poles in the machine (operating frequency is 50 Hz). 3) Connect the items of equipment as shown in Figure 2 at the back of the laboratory sheet (the equipment may already be connected). 4) The DC Motor: Switch on the DC Power Supply to the DC Motor and increase the output. The motor will not start to turn until the supply is approximately 8 - 11V. Adjust the power to the DC Motor to make the Synchronous Generator run at synchronous speed. 5) Synchronous Generator: Switch on the second DC Variable Power Supply with minimum (zero) field excitation current supplied to the generator field rotor circuit. Increase the field excitation current and note how the generator AC line voltage changes as a result. Stop the machine. 3.2. Open-Circuit Test Disconnect the three leads at "SUPPLY 2" of the Synchronising Unit (this leaves the 3-phase Wattmeter still connected to the Synchronous machine). Make sure that the output of the power supply for field excitation current is set to minimum (zero) and turn it on. Calculate the value of Line Voltage that would be 20% above the rated value for the Machine. Increase the DC motor speed to 1500 rpm (speed shown on Motor Speed Monitor). Increase the Field Excitation Current, starting from 0 A, in steps of 0.05 A until the Generator Line Voltage (3-phase Wattmeter page 1) reaches the value calculated above. At each step:- (i) Record the field excitation current and the generator AC line voltage. (ii) Ensure that the DC Motor/Generator speed is maintained at 1500 rpm by adjusting the input voltage to the DC Motor, if necessary. Whenever there is a requirement to maintain the speed shown on the "Motor Speed Monitor" at a particular value, a value within +/-5 rpm is acceptable. Stop the machine when finished. 3.3 Short-Circuit Test With the machine stopped, short circuit the three leads which were unplugged from "SUPPLY2" earlier (connecting the lines at this point ensures that the 3-phase Wattmeter will still be able to measure the current from the machine). Ensure that the field excitation control is at the minimum (zero) position. Turn on the field supply and start the DC motor. Adjust the speed to 1500 rpm. Increase the field excitation current, slowly, so that the line current increases. The field current starts from about 0 A to a maximum of 1 A in steps of 0.05A. Note the field excitation current and the AC line current at each step. As before, ensure that the DC motor/Generator speed is kept constant at 1500 rpm during the test. The Average Line current is shown on Wattmeter page1. However, because the value is low for the first few steps, you may have to take the average of the individual Line Currents (Wattmeter page3). Stop the machine when finished. 3.4 Load Tests 1) Synchronizing the synchronous generator to the supply: Make sure that the "Load Switch" on the Synchronising Unit is Off. With the generator stopped, reconnect the wires between the Synchronizing Unit and the 3-phase Wattmeter. Start the DC motor and set the speed to 1500 rpm. Set the field excitation current so that the measured line voltage on the 3-phase Watt meter is the same as the supply voltage (in this case approximately 45V). Verify that the intensity/rotate switch on the synchronising unit is operating correctly – if it is not, reverse the electrical direction of rotation of the machine by swapping any two of the three output leads. Carefully adjust the DC Motor speed so that the synchronising lamps cycle as slow as possible (once every few seconds). At the correct instant (intensity selected– all lamps off, OR rotate selected – top lamp off, lower lamps both equally bright), turn the Synchronising Unit "Load Switch" on. The Synchronous machine is now connected to the supply and running. The operating conditions of the machine can now be adjusted as required for the application. In this case we will be using the machine as a generator into an infinitely large system (the building supply and national grid(via the transformer in the 3-phase Power Supply)), with the DC motor as a prime mover. 2) Adjust the field excitation current in the AC synchronous generator and the speed of the DC motor to give minimum AC stator current flow in the synchronous generator, i.e. as near to zero current as is possible. In this situation the synchronous generator is neither motoring nor generating, it is just keeping step with the supply and the prime mover is supplying the losses. In an ideal case (no harmonics, ideally wound machine) this current would be zero. In the three experiments below, the three load tests are conducted at approximately the same power level (input power to the DC motor is constant and synchronous generator losses are almost independent of the current) but at three different power factors obtained by changing the field excitation current of the synchronous generator. Use the red cased synchronous stroboscopic lamp to observe the rotor (load) angle at each setting. 3) Increase the power input to the DC motor until the AC line current is about 2/3 of the nominal value (calculated in section 3.1.2). Adjust the field excitation current to the synchronous generator to get even closer to minimum Line current. Note the field excitation current, line current, line voltage, active power, power factor, prime mover input power, and rotor (load) angle. 4) With the power input to the DC motor unchanged, increase the field excitation current to the synchronous generator until the AC line current is at the nominal value. Note readings as above. 5) Reduce the field current to that measured in step (3). With the power input to the DC motor unchanged, decrease the field excitation current to the synchronous generator until the AC line current is at the nominal value. Note readings as above. Open the synchronising switch and stop the machine. Switch Off all power supplies. 4. Deductions 1) From the open-circuit and short-circuit test, and assuming that the short- circuit current varies linearly with field excitation current for the range of values being considered in this experiment, plot on one graph the open-circuit line voltages, short-circuit currents and the synchronous impedances, all against the field excitation current. For the impedance the following relation stands, where Zs is the synchronous impedance, VPh = VL /√3 is the phase voltage on open circuit, VL is the line voltage on open circuit, IPh is the phase current. 2) Determine the base impedance from nameplate values. From the graph of synchronous impedance, determine the value corresponding to rated voltage and convert this to per unit. 3) With each of the results from the load test experiments, determine the power factor and also the per-unit AC line current and voltage. Construct to scale the phasor diagrams using measured values of per-unit voltage, per-unit current, per-unit reactance and power factor. Determine the field excitation current and rotor (load) angle. 4) Comment briefly on the relationship between input and output power at varying excitation levels and on the relationship between excitation and power factor or reactive power, when the synchronous machine is connected to an infinite busbar. 5) Commercial operators of large grid-connected generators operate synchronous generators slightly over-excited to give an operating power factor of 0.8-0.85 lagging/inductive which is not the (electrically) most efficient operating point. Why? What would be more likely to happen if a generator in a large power system is operated under-excited? Rev 2.1 Feb 2016 Rev 2.1a. Jan 2025 Figure 2
Assignment 2 100 marks possible When submitting, zip up your entire Netbeans projects (Try to create and include your “.jar” files of your Noise Removing and Maze projects) into a folder with the following structured file name: lastname_firstname_studentID.zip (using your own name and ID) Assignment 2.zip contains (see the image on the side): • studentapp folder (for entire question 1 project) • noiseremoving folder (for entire question 2 project) • maze folder (for the entire question 3 project) and submit the Assignment 2 zipped folder on Canvas BEFORE the due date and time. Late submissions will incur a penalty. Antiplagiarism software will be used on all assignment submissions, so make sure you submit YOUR work and DO NOT SHARE your answer with others. The project's source code templates are given. Please DO NOT change the package name. Question 1: Binary Tree and Student Sorting (50%) The purpose of this question is to have an opportunity of understanding and manipulate a binary tree and utilize the binary tree to create a program that sorts elements by different fields and can search an element by a searching key. The binary tree is built by a key of the node (Key can be different types) Student Class Create a Student Class that stores student’s name, score, and comments. Name and comments are String type and score is Float type. Student Class has a “toString” method which returns the name, score, and comments of the student and each of the details should be on separate lines. Such as: Student07 Score: 25.759476 Comments 6 //name //score //comments Node Class Create a Node Class that has element, key, and linkers parts. The “element” of a Node class is a generic type. It references any type of object. This project, it references a Student object. The “key” is used to compare different nodes. It must be a Comparable Object and generic type. If the key is a String type, then the tree must be built by the name of the students. If the key is a Float type, then the tree must be built by the score of students. Node Class has a node linker named “left” which references to a node that has a smaller key value. Node Class has a node linker named “Right” which references a node that has a greater key value. Node Class has a “compareTo” method. “compareTo” method takes a Node object in and compares it to the current node by their keys. It returns: = 0: if current node’s element equals to the argument node’s element. < 0: if current node’s element is less than the argument node’s element. > 0: if current node’s element is greater than the argument node’s element. BinaryTree Class Create a BinaryTree Class which builds and manages a binary tree. BinaryTree Class has a Node reference named “root” to reference to the root node of a binary tree. BinaryTree Class has an int variable named “number_of_nodes” to store the number of nodes that a binary tree has. BinaryTree Class has a Node array named “nodeList” to store sorted nodes. (The assignment was designed to output the sorted a txt file. Now, to make it simple, the binaryTree provides a node array to store sorted nodes instead of a text file) BinaryTree Class has an “addElement” method. It takes an element and a key then it creates a Node object. The Node object loads element and key then is passed to addNode() method to attach on the tree. BinaryTree Class has an “addNode” method. It takes a root and a new node to create a tree when the tree is empty or adds a new node to the binary tree. BinaryTree Class has a “reverseOrder” method. It manipulates the binary tree. By default, if we call in-order traversal method, it displays nodes’ details in the order of from smallest key value to the largest key value. If reverseOrder method has been called, then traversal method displays nodes’ details in the order of from largest key value to the smallest key value. The time complexity (Big O) of “reverseOrder” method must be n. Please do not rebuild your tree （ Big O of rebuild a tree is nlog2 n）. Comment your solution, please. BinaryTree Class has a “searchElement” method. It takes a key which is a generic type then creates a target node object which is a Node object and loads key to the target node. The target node is passed to the searchNode() method to do the searching job. “searchElement” method returns a generic type element if searchNode() returns a Node object. Otherwise, it returns null. The target node only contains a key value for searching. An example of how searchNode() method is called in the searchElement() method: Node targetNode = new Node(); targetNode.key = “Student01”; Node resultNode = tree.searchNode(tree.root, targetNode); … BinaryTree Class has a “searchNode” method. It takes a root and target node. It returns a node if it finds the node. Otherwise, it returns null. In this assignment, the searchingResultNode.element references a Student object which contains all the details of that student. For a better understanding of adding and searching students, please see the diagrams after StudentManager class. BinaryTree Class has a “toSortedList” method. It travels each node of the current tree and stores the nodes to the “nodeList” array. BinaryTree Class has a “traversal” method. It travels each node on the current tree and display node.elements’ details in the order of from the smallest key value to the largest key value, or from the largest key value to the smallest key value (it depends on whether reverseOrder() has been called). Helps on reverseOrder() method If you do not know how this can be done, please draw two binary trees with the same data inputs. When you draw the second tree, you put a node with a bigger key value on the left and a smaller key value on the right. Check the difference between these two trees. I am happy to discuss it with you in the lab. Wish it helps You are welcome to add more methods or fields if you need them. Fully comments on the methods of addNode(), searchNode(), reverseOrder() and traversal(). You may lose 20% of the marks if you don’t give the comments to those methods. StudentManager Class StudentManager class has a BinaryTree object named “bTreeScore” which stores Nodes. All nodes are arranged by the students’ scores (node.key is Float type). StudentManager class has a BinaryTree object named “bTreeName” which stores Nodes. All nodes are arranged by the students’ names (node.key is String type). StudentManager class has a method named “addStudent” which takes a String name, a Float score, and a String comments to create a Student object then calls addToTree() twice and passes the Student object with different keys (name or score) to add on different trees. StudentManager class has a method named “addToTree” which takes a Student object and a key (the type of key can be Float or String) to add to the bTreeScore or bTreeName (put a node on different trees) StudentManager class has a method named “findStudent” which takes a searching key and returns a student that matches the searching key by calling binaryTree. searchElement(key). If the student does not exist, it returns null. StudentManager class has a method named “getSortedStudentList” which takes a key (the type of key can be Float or String) and returns a Student array. The elements in the Student array must be sorted by the key. StudentManager class has a method named “reverseOrder” which calls the BinaryTree objects to reverse the order of the trees. You can add more methods or fields as you wish, but you must pass the testing code (StudentApp.java). Question 2 Sorting: Noise Removing Application (20%) Problem: Salt-and-pepper noise, also known as impulse noise, is a form of noise sometimes seen on digital images. This noise can be caused by sharp and sudden disturbances in the image signal. It presents itself as sparsely occurring white and black pixels. See more information: https://en.wikipedia.org/wiki/Salt-and- pepper_noise#:~:text=Salt%2Dand%2Dpepper%20noise%2C,occurring%20white%20and%20black%2 0pixels.) Example (image with Salt-and-pepper noise) An effective noise reduction method for this type of noise is a median filter. Median Filter: A program reads a pixel and its 8 surrounding pixels (This 3x3 block of pixels is called a sliding window in digital image processing) from an image and then finds the median of these 9 pixels. Finally, the median replaces the central pixel. The sliding window moves onto the next pixel and repeats this process until all pixels have been changed (To make the assignment simple, it excludes the bound pixels). Median: the middle score when all the scores are arranged in order of size from the smallest to the highest. If there is an even number of scores, then it is the average of the two middle scores (It will not be the case in this assignment). The code of reading the image, getting pixels, and saving pixels to an image has been done for you. Your task is to find the median for given pixels. To find the median, you need to sort an array of 9 pixels. Example (output image after removing noise) Your task: Please download the “NoiseRemoving.zip” file and extract it to a folder. The project contains two .java files. “ImageProcess.java” and “NoiseRemoving.java”. If you run the project, it loads an image and generates a .jpg file, named “noise_removed.jpg”, but the generated image still contains noise for now. You need to complete the method of “cleanNoise” to clean the noise in the ImageProcess class. “ImageProcess.java” deals with an image. It has a method named “cleanNoise”. There is a gap in the method. You need to add your ArraySort Class to the project and fill the gap to complete the ImageProcess Class (3%). You need to write an “ArraySort” Class. It takes a generic Comparable type of array and sorts array in order. ArraySort Class has an “array” field. It stores a reference of an array. (1%) ArraySort Class has a “setArray” method. It takes a reference of an array and passes the reference to the “array” field. (1%) ArraySort Class has a “quickSort” method. It runs a quick sort algorithm and sorts arrays in order.(3%) DO NOT COPY THE CODE FROM THE CHAPTER 3 EXAMPLES ArraySort + array : E[ ] + setArray(E[ ] array) : void + quickSort() : void PLEASE FULLY COMMENT YOUR CODE OF quickSort() (3%) Answer following questions in your Comments at the beginning of your ArraySort Class code. 1. Is quick sort the best way of finding median? Why? (3%) 2. What is another good way of finding median? Please provide your explanation. (3%) Finally, you need to design a GUI of noise removing application (2%). So, the application can load an image, clean the noise, and save to a new image. And produce a .jar file of this project. (1%) *If you are interested in image process, you may try some open-source library. OpenCV for C/C++ or JavaCV for Java. Question 3: Maze (30%) You are going to design a program. It loads a maze from a maze text file then the program walks through the maze and finds the path from the starting node to the exiting node. Maze text file format: Number of linkers, Number of columns, number of rows (Header of maze) Node’s name, x position, y position, next linked node name, next linked node name … Node’s name, x position, y position, next linked node name, next linked node name Example: 22,7,6 START,0,2,B,A B,1,2,C,K C,1,3,D,E … V,4,1,N,A EXIT,6,2,A,A “A” is the same as null. It means not next linked node on this path (this path has no exit). “W” links to exit. Your task is to write a program. The program does: • Loads a maze txt files (there are two txt files in the project folder. Please do not move them to somewhere else) (3%) • Draws a maze on the panel (You are going to decide how to label the nodes). (3%) • Walk through the maze and find a path from start to exit. (5%) You need to show an animation of how your program finds a path from start to exit. (3%) • Highlight the trail from “Start” to “Exit” on the panel (see image below). (3%) • Display the path from “Start” to “Exit”. (5%) • make sure your program works for both txt files. (7%) GUI is provided. (1%) A jar file is created. A demonstration is available during the lecture. If you missed the lecture, please ask the lecturer to run a demonstration in the lab.
Module code and Title Database Development and Design (DTS207TC) School Title School of AI and Advanced Computing Assignment Title 002: Assessment Task 2 (CW) Submission Deadline 23:59, 12th Dec (Friday) Final Word Count NA Database Development and Design (DTS207TC) Assessment 002: Individual Coursework Weight: 40% Maximum Marks: 100 Overview & Outcomes This course work will be assessed for the following learning outcomes: A. Identify and apply the principles underpinning transaction management within DBMS. E. State the main concepts in data warehousing and data mining. Submission You must submit the following files to LMO: 1)A report named as Your_Student_ID.pdf. 2)A directory containing all your source code, named as Your_Student_ID_code. NOTE: The report shall be in A4 size, size 11 font, and shall not exceed 9 pages in length. You can include only key code snippets in your reports. The complete source code can be placed in the attachment. Question 6: Storage Management (40 marks) In a database storage system, the cache hit rate has a significant impact on its performance. Different cache strategies will result in different cache hit ratios. Now, we have recorded 2 datasets (please download from LMO), containing CPU access requests to memory for a period of time. They both have 10,000 items from addresses 0 to 63. We will simulate the process of the CPU reading and caching data from the memory through a program in the table below (also can be download from LMO) . Please run the program to compare the hit rates of different strategies: Python import random from collections import deque class RandomPolicy: def __init__(self, size): self.size = size self.cache = [] self.name = 'rr' random.seed(207) def access(self, current): if current in self.cache: # hit! return True self.cache.append(current) if len(self.cache) > self.size: # exceed self.cache.remove(random.choice(self.cache)) return False class FifoPolicy: def __init__(self, size): self.size = size self.cache = deque() self.name = 'fifo' def access(self, current): if current in self.cache: # hit! return True if len(self.cache) == self.size: # full self.cache.popleft() self.cache.append(current) return False def run_test(trace, pol): hit = [] for i in range(len(trace)): # update cache hit += [pol.access(trace[i])] return sum(hit) / len(hit) if __name__ == '__main__': # parameters caps = [1, 2, 3, 4, 5] # load trace from file traces = [] for name in ['trace1.txt', 'trace2.txt']: with open(name) as f: traces += [list(eval(f.read()))] # test all strategies strategies = [ FifoPolicy, RandomPolicy, ] # run strategy over trace for i in range(len(traces)): for cap in caps: for Strategy in strategies: pol = Strategy(size=cap) print(f'data={i + 1},tcap={cap},tname={pol.name},thitrate={run_test(traces[i], pol)}') print() You need to analyze the characteristics of this data and analyze why the hit rates of the two strategies are different on the two data sets (20 mark). Design and implement a strategy which can achieve better results than the RandomPolicy strategy on the trace2 data set. Record the hit rates you observed in the table below (with snapshot) (20 marks). Cache Size RR Your Policy 1 2 3 4 5 Question 7: Indexing (30 marks) Consider a hard disk with a sector size of B = 512 bytes. A CUSTOMER file contains approximately r = 40,000 records. Each record includes the following fields: Name (30 bytes), Ssn (9 bytes), Email (30 bytes), Address (50 bytes), Phone (15 bytes), and Birth_date (8 bytes). The Ssn field is the primary key. The file system uses 4KB blocks for allocation. (a) Calculate the number of blocks required for an unspanned organization. Then, discuss how the discrepancy between sector size and block size might affect sequential access performance, and whether you would recommend using a different block size for this scenario. (6 marks) (b) The records are physically ordered on Ssn. Calculate the maximum number of block accesses for a binary search. During system testing, developers notice that batch queries processing large ranges of Ssn values perform. 30% slower than expected when using binary search as the primary lookup method. Provide two possible explanations for your scenario. (6 marks) (c) A sparse index is built on Ssn. Calculate the number of block accesses to retrieve a record using this index in ideal scenario. During usage, it is found that the performance of the index search continues to decline. Identify two potential reasons why the index performance gain is less than theoretical expectations. (6 marks) (d) A multi-level primary index is constructed. During the design review, two proposals are made: Proposal A: Use the standard multi-level index structure; Proposal B: Based on Proposal A, select 10 index blocks and cache them persistently in memory. Calculate the number of index levels needed for the Proposal A. Then, compare the two proposals in terms of implementation complexity and computation time under a workload with 10% of the Ssn accounting for 90% of the queries. (6 marks) (e) A B+ tree index is built with order p = 50. Calculate the maximum number of records a height 4 tree can index. During maintenance, it's observed that, during frequent insertion and deletion operations, the tree height changes frequently between 3 and 4 even with relatively stable data size. Explain what might be causing this fluctuation and suggest one strategy to stabilize the tree height with optimal performance. (6 marks) Question 8: Transaction (30 marks) Consider a database with a relation Account (AccountID, Balance) and initial state: AccountID Balance 1 110 2 10 (a) The following transactions represent a fund transfer (T1) and a real-time balance report (T2) that run concurrently. (10 marks) T1 (Transfer) T2 (Report) 1. begin transaction 1. begin transaction 2. update Account set Balance = Balance - 100 where AccountID = 2. select sum(Balance) from Account; 1; 3. update Account set Balance = Balance + 100 where AccountID = 3. commit; 2; 4. commit; The application requirement states that the report must never reflect a financially inconsistent state. However, under certain database configurations, T2 might output a total of 20 (instead of the correct 120). (i) Explain under which isolation level(s) this inconsistent total of 20 could occur, and describe the exact sequence of operations in a concurrent schedule that leads to this result. (ii) The development team proposes using the SERIALIZABLE isolation level to fix this issue. Critically evaluate this proposal by discussing one key advantage and two potential drawbacks (considering both performance and system complexity) for this specific application scenario. (b) Now consider these transactions: a process adding a new account (T3), and an audit process . T3(New Account) T4 (Audit) 1. begin transaction 1. begin transaction 2. insert into Account values (3, 150); 2. select sum(Balance) from Account; 3. commit; 3. select sum(Balance) from Account; 4. commit; Suppose the application requirement for the audit is that it must have a consistent view of the database throughout its execution. (i) Is it possible for the two SUM queries in T4 to return different values? Analyze this possibility under at least three different isolation levels, providing a brief concurrent schedule for each case where the results differ. (ii) During a system design review, an engineer suggests: "We can just use the REPEATABLE READ isolation level to solve all our concurrency problems in this audit process." Write a brief response evaluating this suggestion. Your response should consider whether this is sufficient, necessary, and practical for meeting the audit requirement. (c) Consider the following observation from production logs: (10 marks) l T5 (Data Maintenance): Inserts 100 new account records in a single transaction. l T6 (Analytics Query): Runs SELECT COUNT(*) FROM Account; twice within its transaction and gets two different results. The team initially diagnosed this as a "phantom read." (i) Under which isolation level(s) is this phenomenon possible? (ii) A DBA comments: "While this looks like a phantom read, the actual impact and the appropriate fix might be different if those 100 new accounts were all inserted with a zero balance." Briefly explain the DBA's reasoning. Why might the business impact and the technical solution be different if the new accounts have a zero balance, even though the phenomenon looks the same?
MEC203: Engineering Graphics and CAD Fall 2025 Autodesk Fusion 360 Project -- 3D Modeling of a Mars Rover 1. The Overall Design Requirements You are the lead designer for NASA JPL. NASA intends to launch the concept design of its next-generation Mars Rover next month. The overall design will be similar to that used in their present product. You are invited to design new wheels, Mobility Systems, Rover Chassis, Acquisition Arm, and lastly assemble them in a Rover. Above are pictures of the 3D assembly of the current product. If your new design is more elegant, your manager will be thrilled. The Mars Rover is car-sized, about 10 feet long (not including the arm), 9 feet wide, and 7 feet tall (about 3 meters long, 2.7 meters wide, and 2.2 meters tall). The diameter of the wheels is 50cm. Figure 1. An illustration of Mars Rover Components. (Source: http://www.cee.org/tep-lab-bench/pdf/MSL.Rover.pdf) Please consider the following requirements in order of precedence: 1) All parts need to be able to function together properly. Interference and undesired gaps in the assembly should be avoided. 2) The shape and dimensions of each part need to be practical. 3) Style. is important but lightweight is essential. 4) Function, manufacturability, and economy should be considered while designing. 5) You are only responsible for designing the general shape of the parts. For example, you don’t need to design a small bearing with detailed cylindrical rollers inside. If you do have detailed parts, which will of course make your design more attractive (getting higher grades), please show them out as your highlight feature in your introduction video. 6) The overall size of the rover should be less than 3x3x3(m). 7) Make motion studies. Please make at least 3 different kinds of motion studies (e.g., wheel revolving, door sliding/opening, or acquisition arm extension). You should make it like it is running in slow motion (of course the rotation of the wheels should not be too fast to observe). More motion studies will boost your grade. Without motion studies, you will get almost zero for the final project. Please highlight your motion studies in your video. 8) All above will be considered part of your project’s grading criteria. If you need help, please contact our TAs. 2. Select your final project group Please sign up for your final project group on Brightspace under “Groups”. Here are two important things you need to know about selecting a group. 1) If you decide to work by yourself, please sign up for the “Final project single group”. This will stop others from joining your group. 2) If you want to work with a team, please sign up for the “Final project team group”. Each group can only have up to 2 students. You should have permission if you want to join another student’s group. We have created a forum on Brightspace under ‘’Discussion”. Feel free to post a thread to find group members. If you try to contact the other group members, the normal email address will be [email protected]. (If you join another’s group without any permission and the other members of the group claim that you did nothing, you will be removed from the group and given a zero for the final project.) 3) Please sign up as soon as possible on Brightspace for your project group. Remember you should have formed your group by Friday, Nov 14. If you have any doubts about forming a group, please contact Ran Zhuang as soon as possible. 4) Note: you will get a 10% bonus point if you work by yourself (single group). 3. Overall guidelines/checklist for the final project 1) Read carefully all files included in the project before you start, to be sure about what you will have to do. 2) Design all the components for your Mars Rover. 3) Make the assembly of the Mars Rover. Check for interference. Use correct/necessary constraints and fit and tolerance. 4) Make motion studies. You should make it like it is running in slow motion (of course the rotation of the wheels should not be too fast to observe). 5) Finish the “Project Report” to summarize your design based on the template (which can be found on Brightspace). 6) Make an introduction video. When the design is completed, prepare an introduction video to show your work. 4. Detailed requirement 1) In the video, you are expected to show how you came up with the idea, how you transfer your idea to a 3D model design, how your design looks like, how it works (the motion studies), and everything else worth saying. Remember to mention and explain the fits and tolerances that you gave to your design for the connection parts. Your introduction video should be less than 5 minutes. 2) This video needs to be uploaded to YouTube and you need to paste the video link to the project number assignment excel. The link will be posted later on Brightspace. (Federal law of FERPA-Family Educational Rights and Private Act protects the privacy of the students so you MUST not include any type of personal information inside the introduction video. Please show and ONLY show your group number at the beginning of the video. Other types of personal information, including but not limited to names, SBU IDs, SSNs, etc. must not appear in the video.) If you choose to speak during the video, make sure your voice can be heard clearly. If you choose to type sentences in the video, try not to block the entire screen with a whole paragraph. Keep it concise and straight to the point. Use any software you can find online to create the introduction video. 3) After finishing everything, please zip all the necessary files to one zipped folder and upload it to Brightspace. Only one of the members of the group needs to submit it. You can create a zipped folder from Windows (select the folder that includes all the necessary files, right clickàSend toàCompressed (zipped) folder). Tip: Try to unzip and open it on a different PC to make sure that everything works before submission. If you open the files directly from a zipped folder, it might not work properly. 4) Do not forget to paste your link when you make your final submission onto Brightspace. No late submission will be accepted unless there is a documented emergency. Computer issues, internet issues, or any other technical issues are not considered “documented emergencies”. 5) Your final project will be graded based on the quality of your introduction video, the model, the assembly, the motion studies, and your report. 6) Contact Lingfeng Gao or Ran Zhuang via email if you any questions. 5. Detailed Final Project Timeline & Deadlines Remember you should have formed your group by Friday, Nov 14 On Brightspace. Deadline 1: Modeling + Overall Assembly: 11:59 PM, Monday, Dec 1, 2025. Deadline 2: The whole project (Modeling + Overall Assembly + Motion studies + Introduction Video + Report etc.): 11:59 PM, Friday, Dec 12, 2025. Upon each deadline, you should upload the required parts/files to Brightspace. Failing to meet Deadline 1 will result in 20% penalties in your total final project grade. Failing to meet Deadline 2 will result in a 0 for your total final project grade. You can change/modify your designs after your submission on Deadline 1. The final grading will be based on the final submission on Deadline 2. Tips: · Make sure that you upload the correct files on Brightspace on time. Not-working/no motion studies or badly assembled designs will get almost zero. · Late projects will not be accepted unless there is a documented emergency. · Computer issues, internet issues, or any other technical issues are not considered “documented emergencies”. Please pay attention to the deadlines (The deadline for submitting the whole project introduction video link).
