Mellin transforms and Dirichlet series are useful in quantifying periodicity phe nomena present in recursive divide and conquer algorithms This note illustrates the tech niques by providing a precise analysis of the standard top down recursive mergesort algo rithm in the average case as well as in the worst and best cases It also derives the variance and shows that the cost of mergesort has a G...

A growth model for porous sedimentary rocks is proposed, using a simple computer simulation algorithm. We generate the structure by ballistic deposition of particles with a bimodal size distribution. Porosity and specific surface area are calculated varying the proportion of small and larger particles. Permeability and it’s variation with porosity are studied. The fractal nature of the pore spa...

On the basis of the analysis of random pulse signal, the mathematical model of the two-parameter random signal is established. Based on which, it is found that the random signal has a non-integer dimension fractal characteristics, and the fractal dimension is the ratio of the count distribution and the number of discrete degree ln σ . Besides, the mass distribution of the particle group is also...

The problem of counting the number of s-t paths in a graph is #P-complete. We provide an algorithm to estimate the solution stochastically, using sequential importance sampling. We show that the method works effectively for both graphs and digraphs. We also use the method to investigate the expected number of s-t paths in a random graph of size n and density d, and develop a model that shows ho...

In this paper we describe a new multiscale model for char acterizing positive valued and long range dependent data The model uses the Haar wavelet transform and puts a con straint on the wavelet coe cients to guarantee positivity which results in a swift O N algorithm to synthesize N point data sets We elucidate our model s ability to capture the covariance structure of real data study its mult...

We present an exact method for speeding up random walk in two-dimensional complicated lattice environments. To this end, we derive the discrete two-dimensional probability distribution function for a diffusing particle starting at the center of a square of linear size s. This is used to propagate random walkers from the center of the square to sites which are nearest neighbors to its perimeter ...

This paper describes how the Fractal image coding takes the long time in its computation. It is its block searching and matching which takes long time. So to overcome this, we use the combination of fractal and wavelet this reduces the computation time. Based on this, we proposed an improved fractal image algorithm based on the wavelet subtree. The algorithm proposed improved fractal image comp...

The influence of stabilizing hydrostatic pressure gradients on the drainage of a fractal porous medium is studied. The invasion process is treated with invasion percolation (IP) in a gradient. Fractality is mimicked by randomly closing bonds of a network. Two length scales govern the problem: the characteristic length of the pore structure xi(s) and a length scale xi(g) above which buoyancy det...