Procedure random pattern generation

The procedure that generates the new random pattern is RND GEN, which is called from widiin the process. The actual procedure is located in die package CONTROL LCX3IC shown in Figure 7.18. Like function declarations, the procedure is split into two parts ... 

Biochemical EPR samples are almost always collections of randomly oriented molecules (frozen) aqueous solutions in which each paramagnetic molecule points in a different direction. In order to generate simulations of these powder EPR spectra we have to calculate the individual spectrum for many different orientations and then add these all up to obtain the powder pattern. Numerical procedures that generate sufficient spectra to approximate a powder pattern are collectively known as walking the unit sphere algorithms. Here is the basic procedure ... 

A method of solving the deconvolution is to divide the particles into size intervals and assume that each one will generate a diffraction pattern aceording to its average size, the intensity of which depends upon the number of particles in that size range. The diffraction pattern can then be manipulated by matrix methods to yield the size distribution. The measured data always contain random and systematic errors which have to be accounted for in the deconvolution step. Several mathematical procedures have been developed which can generate different solutions using the same initial data [148,152]. 

Dr. Sprott and I have been experimenting with replacing the monkey by a computer and having it generate a collection of visually interesting patterns. Unlike the monkey, the computer can be trained to select those images that are likely to appeal to humans. The procedure is to take some simple equations with adjustable coefficients chosen at random, solve the equations with the computer, and display those that meet criteria that we have found to be strong indicators of artistic quality. 

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