| Andrew Cooke | Contents | Latest | RSS | Twitter | Previous | Next


Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

Personal Projects

Lepl parser for Python.

Colorless Green.

Photography around Santiago.

SVG experiment.

Professional Portfolio

Calibration of seismometers.

Data access via web services.

Cache rewrite.

Extending OpenSSH.

Last 100 entries

Real-life Financial Co Without ACID Database...; Flexible Muscle-Based Locomotion for Bipedal Creatures; SQL Performance Explained; The Little Manual of API Design; Multiple Word Sizes; CRC - Next Steps; FizzBuzz; Update on CRCs; Decent Links / Discussion Community; Automated Reasoning About LLVM Optimizations and Undefined Behavior; A Painless Guide To CRC Error Detection Algorithms; Tests in Julia; Dave Eggers: what's so funny about peace, love and Starship?; Cello - High Level C Programming; autoreconf needs tar; Will Self Goes To Heathrow; Top 5 BioInformatics Papers; Vasovagal Response; Good Food in Vina; Chilean Drug Criminals Use Subsitution Cipher; Adrenaline; Stiglitz on the Impact of Technology; Why Not; How I Am 5; Lenovo X240 OpenSuse 13.1; NSA and GCHQ - Psychological Trolls; Finite Fields in Julia (Defining Your Own Number Type); Julian Assange; Starting Qemu on OpenSuse; Noisy GAs/TMs; Venezuela; Reinstalling GRUB with EFI; Instructions For Disabling KDE Indexing; Evolving Speakers; Changing Salt Size in Simple Crypt 3.0.0; Logarithmic Map (Moved); More Info; Words Found in Voynich Manuscript; An Inventory Of 3D Space-Filling Curves; Foxes Using Magnetic Fields To Hunt; 5 Rounds RC5 No Rotation; JP Morgan and Madoff; Ori - Secure, Distributed File System; Physical Unclonable Functions (PUFs); Prejudice on Reddit; Recursion OK; Optimizing Julia Code; Cash Handouts in Brazil; Couple Nice Music Videos; It Also Works!; Adaptive Plaintext; It Works!; RC5 Without Rotation (2); 8 Years...; Attack Against Encrypted Linux Disks; Pushing Back On NSA At IETF; Summary of Experimental Ethics; Very Good Talk On Security, Snowden; Locusts are Grasshoppers!; Vagrant (OpenSuse and IDEs); Interesting Take On Mandela's Context; Haskell Cabal O(n^2) / O(n) Fix; How I Am 4; Chilean Charity Supporting Women; Doing SSH right; Festival of Urban Intervention; Neat Idea - Wormholes Provide Entanglement; And a Link....; Simple Encryption for Python 2.7; OpenSuse 13.1 Is Better!; Little Gain...; More Details on Technofull Damage; Palmrest Cracked Too....; Tecnofull (Lenovo Support) Is Fucking Useless; The Neuroscientist Who Discovered He Was a Psychopath; Interpolating Polynomials; Bottlehead Crack as Pre-amp; Ooops K702!; Bottlehead Crack, AKG K701; Breaking RC5 Without Rotation; Great post thank you; Big Balls of Mud; Phabricator - Tools for working together; Amazing Julia RC5 Code Parameterized By Word Size; Chi-Square Can Be Two-Sided; Why Do Brits Accept Surveillance?; Statistics Done Wrong; Mesas Trape from Bravo; European Report on Crypto Primitives and Protocols; Interesting Omissions; Oryx And Crake (Margaret Atwood); Music and Theory; My Arduino Programs; Elliptic Curve Crypto; Re: Licensing Interpreted Code; Licensing Interpreted Code; ASUS 1015E-DS03 OpenSuse 12.3 SSD; translating lettuce feature files into stub steps files; Re: translating lettuce feature files into stub steps files; A Tale of Two Psychiatrists; The Real Reason the Poor Go Without Bank Accounts

© 2006-2013 Andrew Cooke (site) / post authors (content).

Some Points Related to the Fukushima No. 1 Reactor

From: andrew cooke <andrew@...>

Date: Sat, 12 Mar 2011 18:29:37 -0300

First, a quick summary of what I understand has happened:

 - The reactor is water cooled, but the cooling is not
   passive/convective, so it's critical that there is electrical power
   for valves and pumps.  It cannot "fail safe" when there is no

 - Power is automatically cut on earthquakes, and the core shuts down.
   But heating continues for many hours.

 - There are two backup power systems - diesel generators and
   batteries.  At least the first of these failed, possibly due to

 - Lack of power meant that it was not possible to cool the reactor as
   normal, so the water in the core started to boil, raising pressure.

 - To avoid damaging the core, some steam was vented into the
   surrounding concrete container (the core is in a smaller steel
   container, inside).

 - Unfortunately, some kind of damage occurred inside the core.  I do
   not understand this completely, but the result was that hydrogen
   was generated.  This escaped with the vented steam.

 - The hydrogen ignited/exploded, destroying the outer concrete
   container, but apparently not the steel container around the core.

 - To cool the core it is now being flooded with seawater and boric
   acid.  The boric acid is a damper (it helps kill the nuclear

 - As I type this, there is also a problem with reactor 3.  The above
   is for reactor 1.

So, given the above, there are at least three obvious questions:

 1 Nuclear reactors that do not fail safe?  What the fuck?

 2 How much worse could this have been?  The diesel backup was running
   for the first few hours, when the core was hottest.  If the tsunami
   had been sooner (ie if the plant was nearer the epicentre) then the
   cooling would have failed at a more critical moment.  Would
   meltdown have been possible?

 3 What was the process that created the Hydrogen?  Not just the
   physical/chemical process (it seemed to be something standard, as
   commentators quickly identified "a hydrogen explosion"), but also
   the engineering damage that caused this.  Details here will affect
   the amount of radiation leaked.


Re: your excellent blog

From: andrew cooke <andrew@...>

Date: Sat, 12 Mar 2011 20:05:00 -0300

Hi - thanks for these (my dumb old blog software was confused by your modern
email that included HTML so I am forwarding your comment as quoted text).

From: Gerry Newby <gerrynewby@...>
To: "compute+SomePoints0@..." <compute+SomePoints0@...>
Subject: Re your excellent blog



Hydrogen Source

From: andrew cooke <andrew@...>

Date: Sat, 12 Mar 2011 21:32:46 -0300

The Guardian says that "At 1,200C (2,200F), the zirconium casings of the fuel
rods can react with the cooling water and create hydrogen" which suggests that
was the source of the gas that exploded.  So this is more serious than initial
reports suggested and the word "desperate" is now being used to describe the
use of sea water for cooling.


Good Article on Explosions

From: andrew cooke <andrew@...>

Date: Tue, 15 Mar 2011 17:52:59 -0300



Comment on this post