The Therac 25 Disaster October 2012 1 Introduction The Therac-25 was a machine for cancer treatment manufactured by the Atomic Energy of Canada Limited (AECL) and went down to history as one of the world’s worst software disasters. The machine was released to the market in 1983 and was later involved in at least 6 accidents that lead to enormous radiation overdoses for the patients. One of the major innovations of the Therac-25 was the move to complete computer control‚ which allowed operators
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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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An Investigation of the Therac-25 Accidents -- Part III Nancy Leveson‚ University of Washington Clark S. Turner‚ University of California‚ Irvine Reprinted with permission‚ IEEE Computer‚ Vol. 26‚ No. 7‚ July 1993‚ pp. 18-41. Recall that the Tyler error occurred when the operator made an entry indicating the mode/energy‚ went to the command line‚ then moved the cursor up to change the mode/energy‚ and returned to the command line all within 8 seconds. Since the magnet setting takes about 8 seconds
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2013 EH 300 - 06 PWC 608 I John Wright DR Huntsville‚ AL 35805 October 27‚ 2013 Ms. Cheryl Plaza 102 Business Administration Building Huntsville‚ AL 35899 Subject: Information about PWC Dear Ms. Plaza: In our recent conversation‚ you asked me to research a good company to determine whether it would be a good place for UAH Accounting graduates to work. With your suggestion‚ I researched PWC‚ and I generated an informative report about PWC and the positions open
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PWC 1010-WORKPLACE COMMUNICATION GROUP: TC 101 PRESENTATION DATE AND TIME Date | Time | Venue | Group | Title | Remarks | 3/1/2011 (Week 11) | 8.00 am | Class | Pourya Dashtegoli | Computer Gaming Effects On Human Body | | | 8.15 am | Class | Gan Chee Yong | Internet Services Provider Used by student of MMU | | | 8.30 am | Class | Koo Chee Leong | Food Choice in MMU | | | 8.45 am | Class | Syuhaida Ahmad Ariffin | Effects of Gaming | | 7/1/2011 | 4.00 pm | Class | Ong Jit Jun
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Employee Referral 4 Employee Referral at PriceWaterhouseCoopers 4 New Proposed Employee Referral Portal 5 Implementation of Employee Referral 6 Attrition Management System 6 What is Attrition Management? 6 Present Attrition Management System in PwC 6 Gaps in Present system: 8 Proposed system: 8 Implementation of Attrition Management System: 9 Knowledge Management System 10 Why is Knowledge Management Important in Accounting Firms? 10 Knowledge Management & New Technology 11 Knowledge
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PWCS 23: Principles of diversity‚ equality and inclusion in adult social care settings 1.1 Define what is meant by: - Diversity is about the acknowledgement and the respect of the differences between the people on all of their variety. It‘s about the uniqueness of every each individual and the way he/she contribute for the richness of our society. - Equality. Despite our differences we are equal in front of the society and to each other. This means that everyone deserves to have
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Sacred Heart Convent Higher Secondary School Computer File Submitted to: Submitted by: Sanjay Chauhan Mohi Saxena Class – 10th A Roll No. - 8 Acknowledgement I owe a great many thanks to a great many people who helped and supported me during the writing of this project. My deepest thanks to my teacher
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PWCS 31: Principles of communication in adult social care Identify the different reasons people communicate. One of the reasons people communicate is to understand each other. Understanding is a big part of communication as you have to understand what people problems may be‚ but also to take on board their views and opinions on the situation to be in a position to hopefully sort out their underlying problems. Another reason people communicate is so that they can build positive relationships
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PWCS 37 – Understand health and safety in social care settings Task 3 There are many accidents and sudden illnesses that may occur within a social care setting. Some of the most common ones are: • Slips‚ trips and falls • Burns and scalds • Sprains and strains • Choking and breathing difficulties • Diarrhoea and sickness • Cardiac arrest • Loss of consciousness These accidents and sudden illnesses happen to either the carers‚ service users or visitors. Sprain and strains usually
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