Existing xml query pattern-based caching strategies focus on extracting the set of frequently issued query pattern trees (qpt) based on the support of the qpts in the history. These approaches ignore the evolutionary features of the qpts. In this paper, we propose a novel type of query pattern called conserved query paths (cqp) for efficient caching by integrating the support and evolutionary f...

‎financial market modeling and prediction is a difficult problem and drastic changes of the price causes nonlinear dynamic that makes the price prediction one of the most challenging tasks for economists‎. ‎since markets always have been interesting for traders‎, ‎many traders with various beliefs are highly active in a market‎. ‎the competition among two agents of traders‎, ‎namely trend follo...

This paper proposes a stable modifiable walking pattern generator with a vertical foot motion generated by a central pattern generator that is obtained from the evolutionary constrained optimization. A modifiable walking pattern generator is employed which generates sagittal and lateral position trajectories of center of mass of humanoid robot and a CPG generates the vertical foot trajectory of...

In this paper an evolutionary and developmental model of cell differentiation and cell induction based on differential gene expression is introduced. By introducing morphogenetic gradients on a two-dimensional, cellular grid, the model is able to evolve and generate patterns resembling those found on moth and butterflies. Investigation of biological models has its interest for artificial evolut...

Pattern tree induction has recently been introduced as a novel method for classification. Roughly speaking, a pattern tree is a hierarchical, tree-like structure, whose inner nodes are marked with generalized (fuzzy) logical operators, and a pattern tree classifier consists of one such tree per class. Since a pattern tree can thus be considered as a kind of logical characterization of a class, ...

Time series segmentation is a fundamental component in the process of analyzing and mining time series data. Given a set of pattern templates, evolutionary computation is an appropriate tool to segment time series flexibly and effectively. In this paper, we propose a new distance measure based on pattern distance for fitness evaluation. Time sequence is represented by a series of perceptually i...

Existing web usage mining techniques focus only on discovering knowledge based on the statistical measures obtained from the static characteristics of web usage data. They do not consider the dynamic nature of web usage data. In this paper, we present an algorithm called Cleopatra (CLustering of EvOlutionary PAtTeRn-based web Access sequences) to cluster web access sequences (WASs) based on the...

A brainstem region, the paratrigeminal respiratory group (pTRG), has been suggested to play a crucial role in the respiratory rhythm generation in lampreys. However, a detailed characterization of the pTRG region is lacking. The present study performed on isolated brainstem preparations of adult lampreys provides a more precise localization of the pTRG region with regard to both connectivity an...

Recent convergence analyses of evolutionary pattern search algorithms (EPSAs) have shown that these methods have a weak stationary point convergence theory for a broad class of unconstrained and linearly constrained problems. This paper describes how the convergence theory for EPSAs can be adapted to allow each individual in a population to have its own mutation step length (similar to the desi...

An important mechanism in the generation of biological structures is the production of defined spatial patterns within initially near-uniform cells and tissues. This process can be modelled on the basis of conventional molecular kinetics if there is a shortrange activating effect in conjunction with depletion or inhibition extending over a wider range (‘lateral inhibition’). Such pattern-genera...