Moonconf Papers

The Moonconf version of my new talk "Fetching Moths from the Works: Correctness Methods in Software" went by really quickly, 114 slides in thirty minutes. Fast! Here's the papers I reference in the talk, in order of appearance: "The Case of the Three Engineers vs. BART" :: Gordan Friedlander - 1974 "SIGSOFT Vol. 6 No. 2: Frontmatter" :: 1981 "The BUG Heard 'Round the World: Discussion of The Software Problem Which Delayed the First Shuttle Orbital Flight" :: John Garman - 1981 "Analyzing Software Requirements Errors in Safety-Critical, Embedded Systems" :: Robin R. Lutz - 1993 "Eliminating Embedded Software Defects Prior to Integration Test" :: Ted Bennett, Paul Wennberg - 2005 "Engineering a Safer World: Systems Thinking Applied to Safety" :: Nancy Leveson - 2011 "The Role of Software in Spacecraft Accidents" :: Nancy Leveson »

Photographs - November 2 to November 6

Tourist Couple - London, England 50mm ƒ/8.0 1/80s A tourist couple sits and consults a map of things to do and see in Trafalgar Square. It's a bright, warm day. The night had been unseasonably foggy and chill. Irina and Joe - London, England 50mm ƒ/1.8 1/250s Irina and Joe, on the Ghost Tour Bus. We are in an old-style double decker bus on the top floor, the bottom floor being the backstage for the cast. We'll drive around London for a bit and then do an exorcism. Or perhaps it was a seance? Renovation - London, England 50mm ƒ/1.8 1/100s Two men renovate an apartment in the East End of London. They have an elevated platform and are, »

Photographs - City Code, October 9

Garrett Smith - Chicago, IL 50mm ƒ/1.4 1/125s Garrett Smith put City Code together, spelling out a vague notion over a year earlier to me in Portland. On this day he acts as MC and will later speak himself. It was a brilliant success. Corey Haines - Chicago, IL 50mm ƒ/1.4 1/80s Corey gives a live, Ruby implemented derivation of the lambda calculus. Here he sits for the entire talk, live-coding his way to combinators and computation thereby. Michelle Brush - Chicago, IL 50mm ƒ/1.4 1/50s Michelle gives a delightful tour of the classic datastructures of the 60s and 70s. Given the relatively young age of this field, that's much of the foundational material for graph exploration. Irinia Guberman »

Project Apollo: Reading List

Time to talk books! @bltroutwine by the way, do you have something like an Apollo recommended reading list? Because I would be *so* into that.— Daniel D. Beck (@ddbeck) August 27, 2015 Aside from embedded and real-time systems, my main professional interests are are systems that have some kind of critical failure to them, things that go set fire to their surroundings or spend drastic amounts of money very rapidly. With regard to such systems, it's very hard to beat spacecraft. Life-vehicles are directed explosions and, for instance, lighting a single Saturn V cost about $1 billion in 2015 dollars. I'm interested I'm studying the technical and operational details of NASA in its early days, how decisions got made and how those decisions radiate out through time. »

Photographs - August 15 to August 23

Crumb - Berkeley, CA 35mm ƒ/8.0 1/10s Crumb sits in the study, basking in the light through the window. This is one of the first shots I made with my new lens, a 35mm. Later in the afternoon I would go on a walk-about with my friend Ari, introducing what I know of photography to him. The 35mm was 1/4 for educational purposes, 3/4 for my enjoyment. Commute - Oakland, CA 35mm ƒ/1.8 1/2000s Under the freeway along Broadway a young man begs for money. To my eye there's no convenient place for drivers to stop and hand over money but I don't work the street, merely observe it. The young man's sign reads 'Homeless' along the top, cut out »

Pressure Suits and a Suitcase?

The X-15 is a fascinating project in NASA and aeronautic engineering history. Running from 1958 to 1968 this plane couldn't take off: it was dropped from under the wing of a modified B-52 bomber. You can see it below, the black craft under the far wing. A single occupant craft, the bulk of the X-15 was given over to the powerplant. Early flights used the existing XLR11 rocket, an on-and-burn engine that gave just shy of 7 kilonewtons (kN) from its four combustion chambers. Once throttling technology had been perfected, later flights used the XLR99 engine. This rocket had some punch. From its single combustion chamber it gave 254 kN of thrust at a variable throttle of 50% to 100%. Here's the XLR99 mounted in the tail of »

Photographs - August 7 to August 14

Hope in Curio - San Francisco, CA 50mm ƒ/2.5 1/640 My girlfriend searches through a curio shop. We would both discuss, very seriously, a vintage pull-down wall map picturing a dictatorship of the worker that no longer exists but opt against it on grounds of cost. Dr. Teeth - San Francisco, CA 50mm ƒ/16 1/25 A silent man looks in, briefly, to where we are sitting. He walks casually in front of the bar and I have my camera pointed out, photographing blindly. Other patrons make peace signs, believing themselves to be in-frame. They are to the far left, well out of frame. »

Peculiar Books Reviewed: Grigori Medvedev's "The Truth About Chernobyl"

Let me tell you a joke. Days after the Chernobyl plant melted down General Tarakanov, aware of the extreme importance of clearing the reactor roof of radioactive graphite ahead of the weather, began accepting offers of robots from other nations to do the job. The West Germans, very confident, delivered a tele-presence robot designed for coal mining in dangerous conditions. The robot was lifted onto the roof and set to work, pushing blocks toward the crater. After only a few minutes it ceased to function, ruined by the radiation. The Japanese, also very confident, delivered a autonomous robot to do the job. Placed on the roof it enjoyed some success, pushing over a ton of radioactive material back into the breach before succumbing to the radiation. Seeing that »

Peculiar Books Reviewed: Henry S. F. Cooper Jr.'s "Thirteen: The Apollo Flight that Failed"

In the first Peculiar Books Reviewed we discussed David A. Mindell's delightful book "Digital Apollo" and, in particular, took from the book this lesson: a technical system which puts the human component in a position of supremacy over the machine is more capable of achieving the aim of the system than one which holds humans in a subservient position. That is, ignoring any moral or dystopian considerations, putting people in a role in which they are made to serve machines creates worse outcomes in terms of what has been built. Mindell puts this as the difference between "engineering" and "pilot" mentalities, the former being in favor of full automation–think Werner von Braun's desire have mere passengers aboard a clockwork spacecraft–and the later in favor of manual »

Peculiar Books Reviewed: Francis Spufford's "Backroom Boys"

What is the soul of software engineering as a discipline? That is, who is it that the software engineer can esteem? What characteristics are laudable and worthy of emulation? Physicists have their heroes: Niels Bohr, say, careful to the point of being paralyzed by indecision but brilliant nonetheless, or Richard Feynman, a person, by his own account, in love with the possibility of understanding, in a strictly physical sense, the Universe. Mathematicians can look to Ramanujan or Euler or Erdos. What of software engineers? Two individuals come to my mind. Foremost is Admiral Grace Hopper, inventor of the compiler, promoter of standardization and, least of all, originator of the maxim "It's easier to ask forgiveness than it is to get permission." Another is Donald Knuth, a computer scientist »