The Therac 25 A case study in safety failure • Radiation therapy machine • “The most serious computer-related accidents to date” • People were killed • Reference: Nancy Leveson and Clark Turner‚ “The Investigation of the Therac-25 Accidents”‚ Computer‚ 26‚ 7 (July 1993) pp 18-41. Therac 25 Background • Medical linear accelerator developed by Atomic Energy of Canada‚ Ltd. in mid-1970s • Delivers 25 MeV photons or electrons of various energies • Controlled by PDP-11 minicomputer • Software
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Harold Abel School of Social and Behavioral Sciences‚ Department of Counseling Clinical counseling-related programs: To be considered for admission into the Capella clinical counseling programs‚ you must submit all required application materials. However‚ submitting your materials does not guarantee admission. Program faculty will evaluate your materials and make the final decision on your admission. • Addictions Counseling • Career Counseling • Marriage and Family Counseling / Therapy
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MKTG 489 – FINANCIAL EXERCISES (AY 2015) Due as an Excel (.xls) file via Titanium prior to class EXERCISE 1 Fred Flintstone has just become the product manager for Yabba Dabba Doo‚ a consumer packaged product with a retail price of $2.00. Retail margins on the product are 33%‚ while wholesalers take a 12% margin. Yabba and its direct competitors sell a total of 40 million units annually‚ and Yabba has 24% market share of this total. Variable manufacturing costs for Yabba are $0.09 per unit. Fixed
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Exercise 9 1. A farmer wanted to find the relationship between the amount of fertilizer used and the yield of corn. He selected seven acres of his land on which he used different amounts of fertilizer to grow corn. The following table gives the amount of fertilizer (in pounds) used and the yield of corn (in bushels)for each of the seven acres. Fertilizer Used (x) 120 80 100 70 88 75 110 Yield of Corn(y) 138 112 129 96 119 104 134 a. Find the least squares regression line. a. Calculate r and r2
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characteristics of a direct expansion (DX) air conditioning (A/C) unit. Build Environ 2007;42:1–10. [8] Chen Wu‚ Deng Shiming. Development of a dynamic model for a DX VAV air conditioning system. Energy Convers Manage 2006;47:2900–24. [9] Nasution Henry‚ Wan Hassan Mat Nawi. Potential electricity savings by variable speed control of compressor for air conditioning systems. Clean Technol Environ Policy 2006;8:105–11. [10] Achter bosch GGJ‚ de Jong PPG‚ Kristspit PPG. The development of a convenient thermal
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Exercise 20 1. Which patient scored the highest on the preoperative CVLT Acquisition? What was his or her T score? Patient 3 scored the highest. T score of 63 2. Which patient scored the lowest on postoperative CVLT Retrieval? What was this patient’s T score? Patient 4 scored the lowest. T score of 23 3. Did the patient in Question 2 have more of a memory performance decline than average on the CVLT Retrieval? Provide a rationale for your answer. Yes‚ his decline was from 44 to 23‚ a 21 point drop
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Exercise for Diabetics Diabetes is a group of metabolic diseases in which a person has high blood sugar‚ either because the body does not produce enough insulin‚ or because cells do not respond to the insulin that is produced. This high blood sugar produces the classical symptoms of polyuria (frequent urination)‚ polydipsia (increased thirst)‚ and polyphagia (increased hunger). There are three main types of diabetes mellitus (DM). Type 1 DM results from the body’s failure to produce insulin
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Inventory Exercises 1. At Dot Com‚ a large retailer of popular books‚ demand is constant at 32‚000 books per ear. The cost of placing an order to replenish stock is $10 and the annual cost of holding is $4 per book. Stock is received five working days after an order has been placed. No backordering is allowed. Assume 300 working days a year. a. What is Dot Com’s optimal order quantity (EOQ)? b. What is the optimal number of order per year? c. What is the optimal interval (in working days)
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Physical exercise is any bodily activity that enhances or maintains physical fitness and overall health. It is performed for many different reasons. These include strengthening muscles and the cardiovascular system‚ honing athletic skills‚ weight loss or maintenance and for enjoyment. Frequent and regular physical exercise boosts the immune system‚ and helps prevent the "diseases of affluence" such as heart disease‚ cardiovascular disease‚ Type 2 diabetes and obesity.[1][2] It also improves mental
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1. What are the two groups whose results are reflected by the t ratios in Tables 2 and 3? The group studied was twenty-one elderly women with an average age of 77. Ninety percent of the participants had one or more chronic diseases. Table two represents the programs effects on cardiovascular risk factors and table 3 represents program effects on health behaviors. The t ratios reflected on these tables represents the test results between the pretest and 3 months and again between the pretest and
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