...

The problem of finding the global minimum or maximum of an arbitrary multi-parameter function, F(x, y, z, …), is a common one. The function F could represent the total yield of some system and you want to maximize it, or it could represent the lap-time of a race car and you want to minimize it. If the function F can be analytically expressed, it may be possible to take the derivative and solve F’ = 0 (since F is stationary at the minima and maxima). But in practice there are many optimization problems cannot be tackled analytically. For those cases there are several powerful numerical...

Questions around hydrologic calibration methodologies: 1) The performance of numerous rainfall-runoff models have been tested in many catchments across Australia in recent work (Petheram etal, 2009; 2012; Viney etal, 2009; Waters etal, 2013, in-prep). Two models consistently outperform the others: Sacramento (Burnash etal, 1973) and GR4J (Perrin etal., 2002; 2003). The Sacramento model tends to perform better when assessed over the calibration period, however the GR4J model has fewer parameters and the key question remains: does the simpler model allow more robust calibrations and perform better...

An unscheduled race was held today to make up for rounds cancelled recently. During the last race I entered (some time in January) the car was epic, but that was at night. In comparison, today is sunny, humid, and hot. Tyres were going to behave differently and motors would run hotter. Before my first run I switched from HPI blue springs to MuchMore reds (reminder: the weights go HPI blue, MuchMore grey, HPI silver, MuchMore red, … etc). I had liked the blue springs, but I was now looking for a little more aggression. In Q1 I sauced and baked my tyres (Sorex 36s) and had my ride height at 5.0...

Yesterday I ran the TCX in 17.5 blinky. It was a pretty thin class, as most of the top guys ran other classes. Nevertheless, the car was really fast! The car was good through the slow stuff, and amazing through the fast stuff. I qualified 2nd (in the only qualifier) and won all 3 finals. Here is the setup: TCX_Chas_Egan_2012_DEC_15 <— totally awesome!! Power and speed from the Thunder Power 17.5 was great, but motor temps were still only in the 50s… so more to come from that department. A few weeks ago, at the Nationals, the car was a bit nervous in the rear. Since then I have changed a...