Author: chris

In class, we discussed the use of difference equations for modeling continuous systems. This practice assignment will task you with building a spreadsheet-based simulation (using difference equations) to model the spread of the Hong Kong Flu through New York City in the winter of 1968-1969.

The equations below can be used to describe the cycle of a disease. Equation 1 shows that the susceptible population decreases as more people within the susceptible group become infected (more people become infected based on the infection rate and how many people are already infected). Equation 2 shows that the infected group changes based on the number of people who are susceptible to be infected and how many people are recovering, and Equation 3 shows that the number of people in the recovered group changes based on the recovery rate and the number of already infected people. The state variables in this system are St, It, and Rt. The definition (and units) for each of the variables in the three equations are given below the equations themselves.

Eq 1: St+∆t = St-λStIt∆t

Eq 2: It+∆t = It+[λStIt-(δIt)] ∆t

Eq 3: Rt+∆t = Rt+δIt∆t

Where

St = # in susceptible group at time t (people)

It = # in infected group at time t (people)

Rt = # in recovered group at time t (people)

δ = recovery rate (time / person)

λ = infection rate (time / person)

∆t = the length of time between examinations of the state variables (time)

Use Equations 1, 2, and 3 to build a model of the disease progression over time in Excel. As a hint, you will likely want to use different columns in Excel for: the number of days that have passed, the Susceptible Population (St), Infected Population (It), Recovered Population (Rt). In such a set-up, each row will represent t (the number of days that have passed), and each row will contain a value for “days into disease cycle”, St, It, and Rt. You’ll also need to have placeholders for some input model parameters: infection rate (λ), recovery rate (δ), and ∆t, which you’ll use to fill in the equations that calculate the values for St, It, and Rt. Start your model at “0” days into the disease cycle (this row will represent the initial conditions).

 

Below is some additional information you’ll need to build your model. Simulate your system for 50 days (again, each row in your model should correspond to a day, so you’ll have 51 rows in your model – one for the starting conditions, and one row for each of the 50 days you simulate).

The initial susceptible population of New York City at the time was 7,899,990 people

• The initial number of people infected was 10

• δ = 0.33/day (so the flu lasted 3 days)

• λ = 2.5 x 10-7 per day

• Set ∆t = 1 day

 

NOTE: even with the provided parameter values (for δ, λ, and ∆t), you may observe an unusual data point in the Susceptible Population. That doesn’t mean your model is wrong. Remember, “all models are wrong, some are useful” (we content that this model is still useful, despite the unusual data point).

 

1. your original excel model, named as follows:

“PA_yourlastnamehere.xlsx”. This file should include the following:

a. a table of values St, Rt, and It across the 50 day time frame. Your table will need the following columns: time (days), susceptible population (St), infected population (It), and recovered population (Rt). Each row should calculate the value of the state variables at the current value of t.

b. a table giving the values of the controllable model parameters: λ, δ, and ∆t. (NOTE: the table in part (a) of this question will need to refer to these values in the calculation of state variables).

2. A single, typed word or pdf document with the following information:

a. A list of any assumptions that you think went into the development of this model.

b. A single XY scatter chart (copied and pasted from the Excel file) showing the variables St, Rt, and It as a function of time (time = x axis, the number of people in each group = y axis of graph). The graph should have three lines on it, each line corresponding to a different variable (one line for St, one for Rt, and one for It). Be sure the graph has a title, a legend (showing which color line represents which variable), and appropriate labels for the axes (including units!). The title of the graph should indicate what the recovery and infection rates were for the data you graphed.

c. A second XY scatter chart of St, Rt, and It over time (also pasted from Excel), but which is based on a different λ and/or δ parameter. For this graph too, be sure the graph has a title, a legend (showing which color line represents which variable), and appropriate labels for the axes (including units!). The title of this graph should also indicate what the recovery and infection rates were for the data you graphed.

d. A brief (sentence or two) written conclusion (based on your model) about the impact of changing the recovery and/or infection rates. How did it impact the rate at which each of the groups changed in size?

e. A brief (a paragraph or so) discussion of how a model like this of the spread of disease might be useful (e.g., why might it useful to have a model that allows you to explore different scenarios about the cycle of a disease? who would be likely to use this model?)

After reading  Part One of The Alchemist, answer the following questions thoughtfully, posting your reply below. (More below….)

1.  Santiago makes some terrible mistakes shortly into his journey.  Why does he make the mistakes that he does? How does he react to these mistakes after he has made them? Do you think Santiago will give up on his Personal Legend?  Have you ever felt like giving up on your dreams?  How did you react to obstacles and disappointments?

2. We are introduced to the Crystal Merchant in the last few pages of Part One.  How does he help Santiago?  What kind of person is the Crystal Merchant?  Have you ever had benevolent figures in your life? Have you ever helped others in need?  Explain those events and their effects on you

With the company expanding into several new markets in the coming months, Cable & Moore was anticipating a large increase in sales revenue.  The future looked bright for this provider of television, telephone, and Internet services.  However, management of Cable & Moore was well aware of the importance of customer service in new markets.  If the public had problems with new service and could not quickly and efficiently have their problems solved, demand would quickly erode and it might take years to recover from the bad publicity.  Therefore, management was adamant that there would be enough well-trained customer service representatives to handle the calls from new customers and from potential customers.

 

Based on experience in other markets, the anticipated number of phone calls to customer service was projected.  Given the average call-length, the number of hours of customer-service time from April to August was projected and is shown below.

 

Month                   April         May          June           July           August

Hours needed        22,600       24,600       27,200       28,100       29,500

 

Through experience, management knew that training a new employee well was essential.  Each new employee was put through a 1-month training program, and was assigned to an existing employee for an entire month.  Normally an existing employee would work 160 hours per month.  However, when an employee was assigned to perform training of a new-hire, the productive work hours for that employee dropped to 80 hours per month.

 

During the training period, the trainee was paid $2,000 for the month.  At the end of that time, the monthly salary increases to the standard salary for a regular customer service representative which is $3,500 per month.  In the past, the company lost about 5% of the trained customer service representatives per month due to attrition.  While the company is looking to improve upon this, for the next several months it is anticipated that this will continue.  There will be 170 trained employees at the beginning of April. Management of the company would like to develop a schedule of hiring new employees so that there are sufficient customer service representatives to meet the demand, but this is to be done at the lowest possible cost.

 

Discussion Questions

 

1. Develop a schedule for hiring new employees. What is the total cost of this schedule?
2. Discuss any limitations that exist for this solution.
3. How would the schedule change if the attrition rate could be lowered to 3% per month instead of 5%? What would be the impact on the cost?

 

Project Overview 1. Choose a research question: a) that can be addressed using a t-test b) for which you can collect data to analyze 2. Devise a plan to collect your data 3. Submit a project plan form to the instructor and obtain approval 4. Once your research question and data collection plan are approved, carry out your research: a) Collect data b) Conduct t-test analysis, using guidelines below c) Write your results in a report, using the outline given below 5. Turn in your written report using the link in Module 9 of the course Blackboard site. Data Collection Options: The following are suggestions on where you can collect data. 1. Reliable/reputable websites (e.g., sponsored by the census bureau, professional sports leagues, universities, real estate agencies, car manufacturers, consumer groups, financial institutions, well- known product manufacturers, restaurants/fast food companies, weather tracking agencies, county/city/state/federal government organizations, etc.) 2. Visit to one or more locations where item(s) you are researching can be found (e.g., stores to write down prices, rivers to count turtles, car dealers to write down data about cars, etc.) 3. Other resource by permission (if you have an idea, ask your instructor). Important Note: ERAU and all other universities have strict policies and approval procedures for any research projects that involve collecting data from human subjects. There is not time in this course for you to go through that approval process. Therefore, your project in this course cannot involve directly collecting data from human subjects. This includes conducting surveys. Project Design There are 3 project design options for the t-test project, listed below. To see components and examples for each type of project design, consult the t-test Project Examples Word document or the t-test Project Resources PowerPoint file. A. The 1-sample t-test (Sample size must be at least n = 40.) B. The matched pairs t-test (Sample size must be at least n = 40.) C. The 2-sample t-test (independent samples) (Sample size must be at least n = 50. You may split this across your two samples; for example, you may have two independent samples of size 25, or one of 27 and another of 23, etc. Although your independent samples are not required to be identical in size, it is better if the sample sizes are similar.)

In this assignment, you will investigate the biotic and abiotic structure and function of an ecosystem. You will also investigate how ecosystems recover from disturbance naturally and through human restoration.

Choose 1 of the following ecosystems:

• Tropical rainforest
• Grassland
• Coral reef
• Estuary
• Desert

You will write an APA-style research paper about your choice of ecosystem, including the following elements:

• Describe where this type of ecosystem might be located. Name 1 specific example.
• Describe the structure of the ecosystem.
  • List at least 3 specific examples of both abiotic components and biotic components for the ecosystem type selected.
• Describe the function of the ecosystem
  • In your own words, explain or define biogeochemical cycle.
  • Describe the steps in the carbon cycle as an example of one biogeochemical cycle.
• Describe disturbance and recovery
  • Describe 1 natural and 1 human-caused disturbance to the ecosystem that you have chosen.
  • Describe the damage to the ecosystem for each example, including how the abiotic and biotic characteristics of the ecosystem changed.
• Provide 2 examples of natural resources provided by the ecosystem that you have selected.
  • How can these be sustained into the future?
  • How can humans act as good stewards to assist ecosystem recovery? Provide 1 example specific to the ecosystem that you have chosen

Short Story Essay ( GCSE Creative Writing Higher Tier English)

Your Short story must contain at least 3-4 pages minimum

Your concept or storyline can be based on anything you will want to write.

Your story must also contain a good setting as this is recommended

Resources: University of Phoenix Material: Ballard Integrated Managed Services, Inc., Part 1

Review the Ballard Integrated Managed Services, Inc. (BIMS), Part 1 case study overview.

Prepare a 700- to 1,050-word written report along with a 5- to 7-slide Microsoft® PowerPoint® presentation for the senior management team to present your findings (see Exhibit B for the data set of the second survey).

Address the following:

• Present the BIMS situation as an overview—problem, purpose, research questions, and hypotheses.
• Describe the instrument used for data collection.
• Identify types of data collected—quantitative, qualitative, or both—and how the data is collected.
• Identify the level of measurement for each of the variables involved in the study.
• Code the data if you have not done so. Describe how the data is coded and evaluate the procedure used.
• Clean the data by eliminating the data input errors made.
• Draw conclusions about appropriateness of the data to meet the purpose of the study.

Click the Assignment Files tab to submit your assignment.

Note. As consultants to BIMS, your Learning Team is expected to prepare and deliver a professional product addressing the client’s needs.

Remember that you only need to complete ONE project this quarter.  This option relates to Unit 1.

For this option, you will consider types of human nonverbal communication which can supplement or replace human speech, such as gestures, body language, etc.    You will complete several short activities, and then reflect on what you have learned.

 

These instructions have two parts: General instructions about what I am looking for in the project (page 1) and then specific instructions about what exactly you need to do to complete this project (pages 2 and 3).  There is an appendix about Critical Thinking at the end of the instructions. Be sure to read the instructions carefully before you begin and ask for clarification if you have any questions.

 

General Instructions

The topics covered in this course so far should have encouraged you to think about the similarities and differences between human languages (signed or spoken) and other types of communication.   In this project you will show that you can apply the concepts and information from Unit 1 to new data.

Your write-up should:

• Include appropriate technical terms from Unit 1, either in boldface or listed separately at the end of your write-up.
• Be organized according to the sections in the instructions.
• Give specific details and examples, including counterexamples, exceptions or problems.
• Show critical thinking.  (See the appendix for information about critical thinking.)
• Be at least 700 words in length. Include the number of words at the end of your write-up.

 

Editing tips

• Use an academic register in your writing. Avoid slang, contractions and informal language.  (For example, avoid words and expressions such as “gal”, “tons of”, “sort of”)
• Use correct spelling.  Run your work through a spell-check before you turn it in.
• Avoid run-on and incomplete sentences.
• Complete the Editing quiz (in the Week 3 module) before you submit your work.

 

 

 

The Strategic Management Project will consist of reviewing a specific industry and a specific company within that industry. 

 

The paper should be approximately 12 typed, double-spaced pages, excluding cover page, graphs, charts, bibliography (references), etc.  NOTE:  University instructors have software programs to check papers for plagiarism and to check papers against other student papers as well as published materials.  

 

The following is a suggested outline for the industry analysis:

 

• A broad overview of the industry.
• The industry major competitors, market share of each competitor
• Major products
• Rivalry in the industry/Porter’s 5-Forces analysis
• Key ways which the firms within the industry compete
• Strategic issues the industry faces

 

The company analysis should include:

 

• An overview of the company
• The size of the firm (sales, assets, personnel, etc.)
• The firm’s distinctive competencies (major products, etc.)
• A brief SWOT analysis of the firm

o   Strengths and Weaknesses

o   Opportunities and Threats

• A Porter’s 5-Forces analysis
• The strategic issues facing the firm

 

• Final Strategic Recommendations with supporting rationale

Assignment 4 – Capital Budgeting

 

You are evaluating two mutually exclusive projects with the following net cash flows:

 

Project X    Project Y

Year     Cash Flow     Cash Flow

0       -$1000               -$1100

1            100                   1000

2            300                     100

3            400                     150

4            700                       50

 

The cost of capital is 12 percent.

1. What is each project’s payback period? If the cutoff period is 3 year, then which project would you choose?

2. What is each project’s discounted payback period? If the cutoff period is 3 year, then which project would you choos

3. What is each project’s NPV? Which project would you choose based on NPV rule?

 

4. What is each project’s IRR? Which project would you choose based on IRR rule?

 

5. What is each project’s profitability index? Based on profitability index, which project is preferred?

 

6. What is each project’s equivalent annual annuity (EAA)? Based on EAA, which project is preferred?