Assignment 2: February 10 through February 13

For Lecture: Monday, February 10

Read Chapter 1, sections D and E.

For Recitation: Tuesday, February 11

Read the Leveson paper (reading #4) and also the following two brief reports that are available only on-line: Nuclear Regulatory Commission Information Notice 2001-8 and Multidata response.

The Leveson paper is quite long. Not all parts are equally important. It is a good opportunity to begin practicing how to get the interesting stuff out of a paper without getting bogged down in minor detail. Start with a quick pass, just reading the section headings and the figure captions, to get an idea of the layout of the paper and what kinds of things the authors seem to be trying to communicate. Then skim it quickly, looking primarily at the lead sentence of each section. Now ask yourself why it was assigned as a 6.033 reading, and with that in mind, start looking for the meat of the paper. Long stretches can be skimmed quickly, while other parts require careful study; for still other parts you may be able to say, "yeah, they already told me that". Some of the details are not significant, while others are the basis of important conclusions; you are looking for issues, concepts, and insight that is based on solid technical fact. Finally, don't be dismayed by unfamiliar technical jargon; make a guess about what it means and move on. The authors may explain it two paragraphs later, or two pages later, or perhaps never get around to it. There is a good chance that you will discover that it didn't actually matter. But if it does, you have something to ask about in recitation.

After reading the Leveson paper, write a one-page reading report that addresses the following question:

Lessons learned from the Therac-25 accidents serve as a dire warning of the severity of human casualty due to machine failures. The inventors of the Therac-25 made several decisions on both the level of hardware and software. Can you identify a decision that is critical to the malfuctioning of the machine? What would you do differently to prevent the same kinds of errors from happening?

Remember, use no more than one sheet of paper for your report. We care about conciseness more than the amount of content. Since you will not be able to address every issue in one page, you will have to select only your best arguments for the one-pager. This assignment is due at the beginning of recitation today.

Browse excellent reports from previous years for examples of good writing on one-page reading reports. Also, please check the 6.033 FAQ for formatting instructions.

For Lecture: Wednesday, February 12

Read Chapter 2, sections A and B.

For Recitation: Thursday, February 13

System aphorism of the week