http://www.abnormaldistribution.org We distribute thoughts Tue, 02 Mar 2010 14:36:44 +0000 http://backend.userland.com/rss092 en On Friday evening, 26th February, we suffered an accident. In what is known as the Swiss Cheese Model, stemming in all but name from Jim Reason, all the holes lined up. Pictures of the Swiss Cheese Model abound, for example here and here and here. The idea of the Swiss Cheese ... http://www.abnormaldistribution.org/2010/03/02/we-had-an-accident/ Prof. John McDermid of the University of York asked me if I had documentation for the suggestion in my post on the Buizingen collision that the number of fatalities to trackside workers expected in installing ATP universally on rail tracks might be larger than the number of passenger lives expected ... http://www.abnormaldistribution.org/2010/02/20/passenger-lives-saved-by-rail-atp-versus-installation-risk-to-employees/ At 08.30 am MET (07.30 am UTC) on Monday, 15 February 2010, a commuter train and an intercity train collided in Buizingen, in the greater Brussels region. Initial reports mentioned a "head on" collision, but De Standaard reported (in Dutch) that one train ran into the side of another, ... http://www.abnormaldistribution.org/2010/02/16/mondays-train-collision-in-buizingen-near-brussels-belgium/ There are areas of technological safety which are almost all about people and behavior, for example road safety. Roads form a very open system; there are pedestrians, young children, old people, slow people, cyclists, animals, parked cars, broken-down cars, large users and so on. There are some technical things one ... http://www.abnormaldistribution.org/2010/02/13/thoughts-on-the-luge-crash-in-vancouver/ Abstract We will show that it is not possible to assess probabilistic safety properties for components whose use in a system is unknown to the assessor. The process itself, of assessing a component, creates the context within which a component has the determined probabilistic safety properties. We will further show that ... http://www.abnormaldistribution.org/2009/12/21/the-sil-of-the-valve-on-the-shelf/ Well, folks, the promised "reform of the reform" has started. In my last post, I mentioned some of the troubles the transition from traditional german Diplom to Bachelor's-Master's degree courses has caused at my university. The Rectory has made money available for each faculty to discuss the reform of the ... http://www.abnormaldistribution.org/2009/11/30/reform-of-the-reform/ The university where I teach, the University of Bielefeld, is forty years old this month. It was founded as a «reform university». Everything was in one huge building, as may be seen in this picture. The building has two main social features. First, it encourages interdisciplinary work, since students can ... http://www.abnormaldistribution.org/2009/11/26/to-be-a-master/ I was saddened yesterday to learn of the death of John Stallings exactly one year before. John was a mercurial Berkeley mathematician of occasional genius who, if you believed him, mostly enjoyed sleeping, doing nothing, and various scurrilous activities. Including, on the level of barely scurrilous, BSing with graduate students ... http://www.abnormaldistribution.org/2009/11/25/two-birds-of-different-feathers-2/ The report on the RAF Nimrod accident in 2006 has recently come out and at least British safety engineers regard it as a major event. This is a milestone, and could be a watershed event, in system safety engineering in Britain. Put briefly, the report found that there have been various ... http://www.abnormaldistribution.org/2009/11/08/a-watershed-in-system-safety-engineering/ On 18 August I wrote an essay on eight themes in System Safety Engineering which addressed the use (or not) of so-called formal methods. On 28 August, Rod Chapman of Praxis HIS wrote a note to the University of York Safety-Critical Systems Mailing List which gave some figures for ... http://www.abnormaldistribution.org/2009/09/22/some-figures-from-industry-on-use-and-training-of-formal-methods/