Tuesday, January 4, 2011

On Nested Polynomials

At work we use quartz pressure gauges to measure downhole pressure in a reservoir. The gauges are extremely accurate and employ a clever temperature correction scheme. They are calibrated at a test facility somewhere in the States and sent to us as a kit. The calibrations take the form of nested polynomials, the coefficients of which have to be entered manually into an acquisition system. Apparently computers prefer crunching this form of equation to the regular type. Here is what they look like (more or less).

So just figuring

  • 25 Coefficients per internal gauge 
  • 3 Internal Gauges
  • 4 Coefficients per external gauge
  • 29 Coefficients per Internal/External Combination
  • 9 Possible configurations means 261 coefficients to enter (manually) into the system.
The possibility of typos is tremendous. Luckily the system allows some test values to be input so as to generate a known output. Its fairly easy to check if you've made a mistake. Still its a lot of typing for the two-fingered. Once all the calibrations are entered then the gauges must be phsically checked (in their various combinations ) just to ensure all the points are entered in the right places. Lots of unscrewing and screwing involved here.

This will take all day...I'm already pooped.

Sunday, January 2, 2011

The Prisoner Exchange

Kasiem is a genius.

Imagine being able to pay someone else to do your prison time. Think of the business opportunity. You could even set up an exchanges whereby short term credits in maximum security prisons could be exchanged for longer terms in nicer prisons. Otherwise unemployed people could now find meaningful employment as exchange brokers.The govenment could even generate revenues from licensing aforementioned brokers as well as a service fee levied on each transaction.

Its a win-win as far as I can see.

Saturday, January 1, 2011

Alluvial Shite Fans

There is an escarpment outside our office that runs along the coast for several miles in either direction. Along this escarpment there are hundreds of these alluvial (or fluvial-I can never recall) shite fans. These fans are caused by residents on the top of the escarpment simply dumping their trash over the side of the cliff. There it remains until it either gets covered over with sediments - there are whole vehicles buried here - or until it rains and all this refuse floods the lowlands next to the ocean. Somedays it rains so hard that the manhole covers in the lower city get blown off and there is the spectacle of an artesian shite fountain in the middle of the street.

Sorry about the picture quality. My camera has gone AWOL - permanently it seems.