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Is anything off limits? How ethical is the use of copyrighted material? How ethical is the use of deepfakes?

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Determine Ethics Of Visual Communication

Scenario

In today’s visually intensive world, we have increasing ways that images can be manipulated to create gifs and/or memes as a form of expression. In fact, there are entire apps devoted to these creations. However, freely posting such content on social media can make one wonder if it’s ethically sound to do so.

Furthermore, shows that focus on satire and parody, such as Saturday Night Live, MADtv, The Onion News Network, etc., are heavily reliant on the use of copyrighted content. You are known as an expert in creating memes and GIFs. You have been asked to write a blog post reflecting on these concerns. In preparation, you begin to ask yourself if anything is off limits? How ethical is the use of copyrighted material? And what should people think about deepfakes?

Instructions

Using Microsoft word, write a blog post that addresses the following issues. You must include at least one (1) hyperlink to a web article in each section of the blog post, e.g., a link to an article about the ethical ramifications of deepfakes.

  • Is anything off limits? (this is the introductory paragraph)
  • How ethical is the use of copyrighted material?
  • Must include a hyperlink to a relevant web article.
  • How ethical is the use of deepfakes?
  • Must include a hyperlink to a relevant web article.
  • Social impact of visuals and use of images.
  • Must include a hyperlink to a relevant web article.

Examine the Monthly Sea Ice Extent Anomaly Graph (click on it to make it larger). When was the last year that the sea ice extent anomaly (for the current month) was greater than the 1981-2010 mean sea ice extent?

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Lab with 15 easy questions-Lab 3 – Sea Ice, Plate Tectonics & Earthquakes

  1. In the study of climate change, the concept of “anomalies” often comes up.  What is a temperature anomaly?  See figure 1-2 and p. 240 in your textbook (2)

A temperature anomaly refers to the difference between the average temperature in a given location for a specific period of time (usually 30 years) and the temperature for a particular day, week, or month. The temperature anomaly is typically expressed as a deviation from the long-term average, usually measured in degrees Celsius or Fahrenheit.

Temperature anomalies are used to track changes in temperature over time, particularly as they relate   to climate change. By comparing temperature anomalies over a period of years or decades, scientists can observe trends in temperature that can help them understand the impacts of climate change on the environment.

  1. The National Snow & Ice Data Center monitors sea ice coverage and concentration.  The Sea Ice Index is calculated from this coverage to assess the change in sea ice compared with the 30-year average.

Go to http://nsidc.org/data/seaice_index (Links to an external site.)Links to an external site..

The “median ice edge” line on the map (pink line) represents the 30-year median ice extent.  How does the current sea ice extent compare to the 30-year median? (2)

If the current sea ice extent is below the 30-year median, it means that there is less sea ice now than there was on average during that 30-year period.

  1. Examine the Monthly Sea Ice Extent Anomaly Graph (click on it to make it larger).  When was the last year that the sea ice extent anomaly (for the current month) was greater than the 1981-2010 mean sea ice extent? Hint: The 1981-2010 mean sea ice extent is the 0% value on the anomaly graph.(2)
  2. Given the 1981-2010 mean sea ice extent labeled in the lower left-hand corner of the graph, calculate the current sea ice extent in millions of square kilometers. Show your work. Hint: Subtract the current sea ice extent anomaly, which you can read in the graph expressed as a percent, from the 1981-2010 mean.  You can check your answer against the “Total extent” value given on the Sea Ice Extent map.(3)
  3. How does the trend in the extent anomaly graph compare with that of the temperature anomaly graph of Figure 4-34(Links to an external site.)Links to an external site. in your textbook?  What is the significance of this? (3)
  4. What is the speed of Santa Cruz? (round your answer to the nearest hundredth) (2)
  5. What is the speed of Santa Rosa? (round your answer to the nearest hundredth) (2)
  6. Using page 128 (p.118 in 22nd edition) in your atlas, determine how many miles apart are Santa Cruz and Santa Rosa. Show your work (round your answer to the nearest whole number) (3)
  7. You can calculate how fast the two cities are moving toward each other by adding up the absolute value of their speeds. Based on the distance that you calculated in the previous question, and the speed at which the two cities are moving toward each other, how many years will it take for Santa Cruz and Santa Rosa to “meet”? Remember that Speed = Distance/Time.  Note that 25.4 mm = 1 inch, 12 inches = 1 foot, 5280 feet = 1 mile, 1 mile = 1.61 kilometers (round your answer to the nearest whole number). Show your work. (3)

10.Using the Option settings (gear symbol on the upper right), switch to 30 Days, Significant Worldwide and zoom out to the World. Where did the two strongest of these earthquakes occur and what was their magnitude? (2)

  1. Switch to 30 Days, Magnitude 4.5+ U.S.What can you say about the pattern of these significant earthquakes across the world? (2)
  2. Zoom to California (click on the globe icon beneath the +/- zoom buttons). Switch to 7 Days, Magnitude 2.5+ U.S. Turn on the U.S. Faultslayer. What pattern do you notice in the distribution of earthquakes in the western U.S.? (2)
  3. Where did the strongest of these earthquakes occurin the western U.S. and what was its magnitude? (2)
  4. Go to the USGS “How Much Bigger…?” Calculator Links to an external site..  Enter the magnitude of the strongest earthquake you found in the previous question.  How much stronger (by energy released) was this earthquake than a 2.5 magnitude earthquake (one which is barely perceptible to humans). (2)
  5. Earthquakes occur at faults.  Describe how the presence of a fault may result in an earthquake. See p. 436 and Figure 14-58 in your textbook. (2)
  6. Zoom to North America (use the “Zoom to U.S.” option).  How many “Significant”earthquakes have occurred in North Americain the last 30 days (use the “30 days, Significant Worldwide” option)? Where have these earthquakes occurred? If near a plate boundary name the type of plate boundary (you should look this up). (3)
  7. Switch to 7 Days, Magnitude 2.5+ U.S.Approximately how many 2.5+ magnitude earthquakes occurred away from plate boundaries (click on the “Only List Earthquakes Shown on Map” checkbox and pan/zoom around to get an approximate count)?  Where? (3) What are the best explanations for the occurrence of these specific earthquakes(you should look this up)? (bonus +1)

Do you agree with Global Tech’s vision? Why or why not? Based on what you think might be an appropriate vision for the company, come up with a good mission statement for Global Tech, and explain why it is a good mission statement.

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Case analysis and short answer

Part A: Short-Answer Questions (6 questions)

1) The United States is, by many accounts, facing an opioid crisis. Among various hypotheses that have been advanced for this phenomenon, one hypothesis is that increased pharmaceutical advertising on television causes increased substance dependency. Evaluate the main pros and cons of using each of the following four research instruments to collect data that will allow for testing this hypothesis: survey questionnaires, qualitative methods, eye-tracking, and neuro-methods. Which would you recommend using and why?

3) View the following advertisements for Dove Men+Care: Advertisement 1 (https://www.youtube.com/watch?v=zAW7iWhjJbU) and Advertisement 2 (https://www.youtube.com/watch?v=KJDIDKQIMNI). Write down two appropriate positioning statements for Dove Men+Care, one based on each advertisement. Evaluate the evolution in Dove Men+Care’s positioning from Advertisement 1 to Advertisement2.  Explain whether you think this evolution was a good decision, and why.

4) Consider any brand that you are extremely loyal to. Specific to this brand, use the Brand Resonance Model to explain how the various brand building blocks have resulted in evolving levels of brand equity for you as a consumer over time. (2 points)

5) A hoverboard is a levitating board similar in shape and size to a skateboard; it is typically used for personal transportation (see https://en.wikipedia.org/wiki/Hoverboard). Although long considered fictional, there have been increasing recent attempts to create real hoverboards. Explain how the various characteristics of hoverboards as an innovation are likely to influence their rate of adoption among the general populace. (2 points)

6) According to USA Today’s Ad Meter, “Forever” from The Farmer’s Dog was the highest-rated Super Bowl LVII commercial (you can view the commercial at https://www.youtube.com/watch?v=IAIo-pUDl0sLinks to an external site.). What are the commercial’s likely IMC objectives, and why do you think so? Of Cialdini’s principles, which ones does the commercial use? Explain how the commercial’s use of these principles might influence consumers and help the company meet its objectives for the commercial.

 

7) Warby Parker is a retailer of eyeglasses, sunglasses, and contact lenses. Founded in 2010 as a completely online company, Warby Parker was able to manufacture its own eyewear and leverage its direct channel structure to sell prescription eyeglasses at $95, compared to the $200 or higher charged by major eyeglass retailers. Additionally, for each pair of eyeglasses that Warby Parker sells, the company donates a pair of eyeglasses to non-profit organizations that distribute the eyeglasses among the one billion people worldwide who otherwise lack access to eyeglasses. Based on this information, explain the various ways in which Warby Parker’s holistic marketing approach enables its channel strategy, pricing, and corporate social responsibility (CSR) initiatives to support each other.

 

 

Part B: Case Analysis (4 questions)

Use the following case based on a real company to answer the questions in this part:

Global Tech LLC (Global Tech) is a privately-owned information technology (IT) and business processing outsourcing (BPO) services company that was founded in 1999, with headquarters in “Silicon Valley,” California. In 1999, the company also started operations in Hyderabad, India, and its business model was simple. The US operations would generate business from US clients, and the Indian operations would fulfill the business by providing IT and BPO services. The company’s vision was “To be the best IT and BPO services company in the world.”

1999 was a “boom” time for the IT industry, especially companies with Indian operations, who were able to leverage cost advantages to “patch” older software for Y2K compliance. To aid business development, Global Tech quickly hired 10 salespeople in the US, and this helped the company reach $101M annual revenue within five years. Although the company is tight-lipped about current revenue and profit, analysts estimate that revenue had a compound annual growth rate (CAGR) of 5% from 2004 till today. The company has also grown from around 1,000 employees in 2004 to 5,021 employees today, most employed in India, but also including 51 US-based salespeople. Global Tech’s competitive strategy was and still is driven to a large extent by cost differentiation, using hourly billing rates as low as $15 to acquire new clients, and then providing satisfactory services to secure repeat business at similarly low billing rates, resulting in gross margins of less than 35% as opposed to the 40% to 45% margins made by other companies in the same industry.

A simplified value chain of the IT industry suggests that companies at the high end engage in differentiated activities that are more proprietary and less imitable, allowing them to appropriate more value. These include firms such as Google, SAP, and Microsoft, who engage in R&D services to develop their own products and services. IT consulting companies such as IBM and Accenture engage clients to understand business and functional requirements that can be fulfilled by products or services from companies such as Google and SAP. IT consulting companies then pass this information on to their IT services SBUs or other IT services providers. IT services providers work on these requirements to develop, port, maintain, or test IT systems and software that meet clients’ requirements. Development is the most lucrative as it allows providers to create new solutions that typically command a higher price, followed by porting, which involves migrating an existing solution from one environment to another (for example, Windows 8 to Windows 10). Maintenance and testing are less lucrative as they involve troubleshooting or validating existing solutions, although maintenance comprises the largest volume of business for many companies. IBM and Accenture have their own IT services SBUs, and are major players in this space, along with HP, Fujitsu, and Indian IT companies such as Tata Consultancy Services (TCS) and Infosys Limited. Finally, BPO services in the IT industry typically focus on call center operations and other back office operations such as finance and accounting services and human resources management services, with Capgemini and Genpact among the major players. For the most part, Global Tech is focused on IT and BPO services, although it also provides IT consulting services to some clients.

A majority of the company’s business comes from North America, with three clients – Costco Wholesale, Safeway, and WellPoint Health Networks – making up almost 25%. In addition to these three clients, the company has almost 500 smaller US clients in various industries such as banking & financial services, energy & utilities, media & entertainment, public sector, retail, and telecommunications. Most of the work for Costco and WellPoint involves the maintenance of legacy mainframe solutions, but this has been decreasing over time as clients port their old mainframe solutions to more stable solutions from Oracle and Microsoft. The work for Safeway, on the other hand, involves a balanced mix of development, porting, and maintenance, and the work for the company’s other clients broadly follows its balanced mix for Safeway. Global Tech also has alliances with IBM and Microsoft, which allow it to position itself as a preferred IT services provider for products, services, or consulting solutions involving these companies.

Although the company has been around for almost 20 years, it has grown organically along many dimensions, and the senior management has been exploring some strategic moves to set course for the next ten years and beyond. For starters, almost everyone on the senior management team felt that the company needed a clear mission statement that went beyond the company’s vision. Additionally, they agreed on the need to have a clear positioning, but they could not agree on what would be best for Global Tech in terms of the customers it should focus on, and what message it should highlight in its marketing communications. At a recent meeting, the VP of Marketing also stressed the need to be more mindful in redesigning the company’s logo (currently just the company’s name in plain, black text), with special focus on a distinct color palette that would also be consistent with the company’s positioning.

Finally, the CEO repeated an issue that she had been highlighting for some time: that the company should be more scientific in the way it decided on salesforce staffing. She felt that the company’s salesforce had pretty much grown at the same rate as the rest of the company, with growth across the rest of the company being driven by increased headcount at the offshore operations. Although offshore headcount might indicate volume of business and, thereby, appropriate salesforce size, given that up to 33% of the offshore team was sometimes on the “bench,” without active projects to work on, it was possible that the company didn’t need as many salespeople either. On the other hand, it was possible that the current salesforce was operating at maximum capacity, so adding more salespeople might generate more business, but it was difficult to say for sure.

The VP of Sales was tasked with validating whether the current salesforce size was appropriate or not. To determine this, he decided that he would continue with the company’s current expectation that, on average, each salesperson made one daily sales call per client or prospect. He knew that the annual overall salesforce objectives included getting 10 new clients, but that this would require engaging with at least 100 prospects. He also wanted to distinguish between call frequency for prospects (twice a week) and clients (weekly for 10 of the company’s biggest accounts and fortnightly for the other accounts, in order to keep repeat business flowing in small increments at regular intervals). Armed with this information, he set out to address the task before him.

 

8) Perform a SWOT Analysis for Global Tech. Please ensure that you analyze the main issues (as opposed to identifying and listing case facts).

9) Do you agree with Global Tech’s vision? Why or why not? Based on what you think might be an appropriate vision for the company, come up with a good mission statement for Global Tech, and explain why it is a good mission statement.

10) Explain which customers Global Tech should focus on, and what its key message to these customers should be. Based on the customers and message, what would a good brand logo look like, and why?

11) Estimate and explain what you think the company’s salesforce size should be.

 

Create a new database, and name it ABCPublish-FirstnameLastname. Save it onto your computer. In this database, create two tables (Authors and Textbooks) from scratch, using the field information and data records provided above.

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DISCUSSION QUESTION

Your Tasks in this Assignment
1. Create a new database, and name it Publishable-FirstnameLastname. Save it onto your computer.
2. In this database, create two tables (Authors and Textbooks) from scratch, using the field information and data records provided above.
3. Import the third table – Authorship Log from the spreadsheet file provided.
4. Create a relationship board with all three tables and two relationships.

Your completed relationship board should look similar like the data model on Page 1 of this instruction document (symbols would be slightly different though).

Discuss the eight-step fraud risk assessment process presented in SAS No. 99 and explain how performing a risk assessment will help to prevent or detect fraud. What is required by Section 404 of the Sarbanes-Oxley Act? How could this new requirement prevent or detect fraud?

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Ac465 unit3

Forensic accountants must ensure that their activities comply with the laws and regulations of the legal, regulatory, and professional environment. In this assignment, you will examine two components of the forensic accountant’s regulatory system: SAS No. 99 and the Sarbanes-Oxley Act of 2002.

In a 2-3 page informative essay, please address the following:

  1. Discuss the eight-step fraud risk assessment process presented in SAS No. 99 and explain how performing a risk assessment will help to prevent or detect fraud.
  2. What is required by Section 404 of the Sarbanes-Oxley Act? How could this new requirement prevent or detect fraud?

Assignments Submission Requirements

  • Viewpoint and purpose should be clearly established and sustained by providing specific examples to support your assertions.
  • Use correct grammar, punctuation, and spelling.
  • Writing should be well ordered, logical, and unified, as well as original and insightful.

Written response must follow the following formatting guidelines:

  • Microsoft Word document
  • Title page
  • Double-spacing, 12-point Times New Roman or Arial font, one-inch margins
  • APA in-text citations
  • APA reference list of at least two references
  • Page length requirements: 2–3 pages, not counting the title page and reference page

Using the Five Approaches Table Template, write the key points for each heading and qualitative approach. Use your own words for the table; do not simply cut and paste direct quotes from the reading.

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Five Approaches Table Assignment Instructions

Overview

Quantitative and qualitative researchers both collect data; however, their data collection methods differ. While quantitative researchers rely on numerical or measurable data, qualitative researchers depend on personal accounts, namely interviews, to understand a phenomenon. Quantitative researchers use differing designs in conducting their research to include experimental, quasi-experimental, and descriptive. On the other hand, qualitative researchers use several approaches when conducting research to include phenomenology, case study, ethnography, narrative, and grounded theory. In this first assignment of EDUC 817 Qualitative Methods of Research, you will begin to explore the five main approaches qualitative researchers use to understand a specific phenomenon, particularly in education. As you learn more about the five approaches, keep in mind that at the Liberty University School of Education, should you choose to pursue a qualitative dissertation, you will utilize either a phenomenology or a case study.

Instructions

This assignment will help you organize the critical elements for five major qualitative research approaches. Using the Five Approaches Table Template, write the key points for each heading and qualitative approach. Use your own words for the table; do not simply cut and paste direct quotes from the reading. You may bullet your information in each section of the table. The process of writing the correct phrase for each area will help you understand the similarities and differences between these five common approaches. Review the red typing in a few of the cells to see examples of the information you must fill in. Delete these examples as you complete the table.

Rawls and Bentham explain their basis of decision making in justifying their decision. Explain the basis of your decision. Justify your decision. What will this mean in future decisions that you make as a legislator? What are the pros and cons of your decision making process?

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Signature Writing Assignment 1

You are a Texas Senator on a three person Senate Committee on Education.  The committee has been given an extra $2 million by the Comptroller of Public Accounts who shows that there has been a significant increase in tax revenue in the state.  The money will go toward college scholarships in public universities.  The committee’s job is to decide on proper allocation of the funds and make a recommendation to the full Senate.

Senator Rawls represents an economically challenged portion of urban Dallas.  Senator Rawls grew up in this neighborhood and expresses that poor people are the individuals most in need, and that all extra resources should go to those most in need.  Senator Rawls recommends that all scholarships be need based.  Senator Bentham represents and was raised in an upper middle class portion of Houston.  Senator Bentham says the money should go to the students who are excellent high school students who want to major in STEM fields.  Senator Bentham says the investment will produce and overall healthier society and that ability to succeed in college in an important field is more import than being in personal need because the investment is more likely to produce more overall good in things like medical procedures, drugs, and infrastructure.

You are the third and deciding vote.  In 300-400 words, explain the following in the order outlined by the numbers below:

  1. What is your decision on how to distribute the money?
  2. Rawls (give to those most in need) and Bentham (give to those who will give the most back) explain their basis of decision making in justifying their decision. Explain the basis of your decision.  Justify your decision.  What will this mean in future decisions that you make as a legislator?  What are the pros and cons of your decision making process?
  3. What about general experiences in your life caused you to have the core beliefs to make your decision?

Finds 3 outside resources, either academic op-eds or journal articles, supporting your viewpoint. When citing these sources, please include a bibliography in the Chicago style. Be sure to convey who your source is, and why they are a relevant expertise? This assignment will be due 3/28 at midnight.

How do these programs meet the needs of your stakeholders? How are these programs not meeting the needs of your stakeholders? Based on what you’ve researched, what are some of the needs you will be addressing in your ideal family literacy program?

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Family Literacy Part 1

Assignment Details EEC3400 RVE 1231

  • This can include sharing articles, links, videos, etc.
  • This is meant to be a conversation with the guiding questions serving as a facilitator.
  • Using the guiding questions below, discuss how you will use what you have learned about your literacy issue to begin developing your ideal family literacy program.

Questions:

Section I (Allocate approximately 10 minutes):

  • What have you learned about your literacy issue?
  • How does your literacy issue affect family literacy?
  • Who are the stakeholders pertaining to your family literacy issue and describe their different perspectives?
  • What are the family literacy programs currently in place as it pertains to your topic?

Section II (Allocate approximately 10 minutes):

  • How do these programs meet the needs of your stakeholders?
  • How are these programs not meeting the needs of your stakeholders?
  • Based on what you’ve researched, what are some of the needs you will be addressing in your ideal family literacy program?

What is the firm’s corporate-level strategy? If it operates in more than one business, do the businesses share or trade resources and if so, which ones.

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Business Question

Student Name

1.    What is the firm’s corporate-level strategy?
 
 
 
 
2.     If it operates in more than one business, do the businesses share or trade resources and if so, which ones. 
 
 
 
 
 
3.     What is the firm’s primary mode of diversification?
 
 
 
 
4.     What mode of diversification and growth would you recommend?

 

Calculate the alternating stress amplitude (equal to the maximum normal stress) for each load, and plot this on a graph as a function of logl0 number of cycles N. (Should be a semi-log plot.)

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Fatigue Testing

EXPERIMENT # 4

Safety first!

  1. Proper protective eyewear must be worn while operating the fatigue tester.
  2. Place the guard shield in place before starting a fatigue test.
  3. Never touch the sample while it is rotating.
  4. Caution: the sample may be hot after the test.

 

Objectives

  1. To determine how surface finish affects fatigue life.
  2. To determine how fillet radius affects fatigue life.
  3. To observe fatigue fracture surface markings and be able to differentiate fatigue from fast fracture markings.
  4. To generate a Wöhler diagram (an S-N curve) and extract information relating to fatigue limit, fatigue strength, and fatigue life.

Background

Material fatigue is a well-known situation whereby rupture can be caused by a large number of stress variations at a point, even though the maximum stress in the material is less than its yield stress. As the number of load cycles increases, the permissible stress level declines. Fracture is initiated by tensile stress at a flaw in the material (the flaw may be microscopic or macroscopic). Once started, the edge of the crack acts as a stress raiser and assists in propagation of the crack until the reduced section can no longer carry the applied load, and the part fails.

While it appears that fatigue failure may occur in all materials, there are differences in the incidence of fatigue. For example, mild steel is known to have an ‘endurance limit stress’ below which fatigue fracture does not occur, no matter how many loads cycles the material experiences, which is known as the fatigue limit. With non-ferrous materials, such as aluminum alloys, however, there is no such limit. As a consequence of these differences, there are two design methods. With a material like mild steel, the stress range can be kept below the endurance limit to ensure failure will not occur. Alternatively, one can design for a specified number of stress variations, on condition that the part will be replaced at that stage. The latter method is quite common with aircraft where the use of aluminum is widespread.

Fatigue strength is also significant in machine design. When designing a part for fatigue strength, an engineer uses results from a fatigue test. However, when designing for infinite life (millions of cycles), such results may not exist and will take too long to determine. In such a case, interpolation from the measured fatigue data will be used instead. To introduce this very complex subject in a simple way, the apparatus demonstrates the classical fatigue experiments carried out by Wöhler. He selected the method of reversing the stress on a part by employing a cantilever beam rotated about its longitudinal axis, therefore the stress at any point on the surface of the beam varies sinusoidally. A Wöhler diagram (stress-number (S-N) curve) can be created by repeating the experiment at many different loads and recording the number of cycles until failure occurs.

 

Fatigue Testing Machine

The Gunt Fatigue Testing Machine provides a simple way of observing the effect of fillet radius and surface smoothness on a material subjected to fluctuating flexural stresses. The fatigue tester is driven by an induction motor, which is connected on one side to a counter mechanism. The tapered test piece is attached to a very stable shaft in between two spherical ball bearings. The loading fixture is attached to the shaft at the other end. The loading device consists of a spherical ball bearing and a micro switch that automatically switches off the motor when the fracture occurs. The loading on the test piece can be increased by turning the loading wheel clockwise. The force applied to the test piece by a spring can be varied from 0-300 N. A load cell measures the applied force. The number of load changes and the applied force are read directly from the LCD.

 

Basic Principles

In the fatigue apparatus, the specimen acts as a clamped beam (left end) under a concentrated force F (right end). This induces a triangular bending moment along the length of the specimen, with a maximum bending moment of . As shown in the figure, a is the length of the specimen. The bending moment is largest at the clamped end and drops to zero at the free end. We expect the specimen to fail where the loading is highest, i.e., at the clamped end.

Under pure bending, the normal stress varies in the cross-section as well, going from zero at the neutral axis (the center of a circular cross-section) to a maximum/minimum value at the outermost surface of the specimen. One side of the beam is in tension while the other is in compression. The maximum normal stress in a beam, s, is:

Where Mb is the applied moment, c is the distance from the centroid to the outermost surface (in this case, r), and I is the moment of inertia about the centroid, which for a circular cross-section, is:

The cyclic stress experienced by a specimen during a fatigue test is composed of a constant part, the mean stress, which is caused by an initial load, and a superimposed cyclic part with an alternating stress amplitude. In this experiment, the bending moment is fixed and the specimen is rotating, which results in an alternating, sine-shaped bending stress, with a mean value () of zero. The alternating stress amplitude in the specimen is a function of the applied bending moment (described above), and the geometry (described below).

In this experiment, the alternating stress amplitude, , is equivalent to the maximum normal stress in the beam. Combining all equations, the alternating stress amplitude is given by:

 

Test Procedure

You will run the fatigue experiment on three different specimens of heat-treated steel, details of which are shown in the table below:

 

Specimen Fillet radius (mm) Surface roughness Rt (μm) Notes
1 0.5 4 Sharp corner, smooth
2 2 4 Curved corner, smooth
3 2 25 Curved corner, rough

 

As the time required for a fatigue experiment is prohibitively long for small loads, all three specimens will be loaded with a relatively high force of 200 N in this lab.

  1. Measure the diameter of the specimen and inspect the surface roughness.
  2. Insert the specimen into the equipment.
  3. Measure the distance from the neck to the specimen’s contact surface with the bearing.
  4. Refer to the PDF “Fatigue Testing User Manual – For Students” for specific instructions on setting up and running the experiment.
  5. Once the experiment is complete, record the number of load cycles to failure (N) and calculate the maximum normal stress in the specimen.

 

It takes much longer to create a complete S-N curve given the nonlinear nature of the response. Data were taken on five #3 specimens, and the results are shown in the table below:

Number Load (N) Stress (N/mm2) Cycles to failure, N Duration (min)
1 200   14030 5
2 170   48800 17
3 150   167000 60
4 130   455000 162
5 120   1280800 457

For these specimens, the length was a=100.5 mm, and the diameter d=8 mm

  1. Calculate the alternating stress amplitude (equal to the maximum normal stress) for each load, and plot this on a graph as a function of logl0 number of cycles N. (Should be a semi-log plot.)

 

Report

A full lab report is to be submitted. The lab report should include the following:

  1. Explanations of the fatigue limit, fatigue strength, and fatigue life.
  2. Maximum normal stress calculation for each load.
  3. Discussion about the fractured surface cross-section and identification of the cause of the rupture.
  4. How was the lifespan affected by fillet radius? Compare specimens #1 and #2.
  5. How was the lifespan affected by the surface smoothness? Compare specimens #2 and #3.
  6. An S-N curve (Wöhler diagram) for the experimental data provided for specimen #3.