We introduce a model of parallel computation that retains the ideal properties of the PRAM by using it as a sub-model, while simultaneously being more reflective of realistic parallel architectures by accounting for and providing abstract control over communication and synchronization costs. The Hierarchical PRAM (H-PRAM) model controls conceptual complexity in the face of asynchrony in two way...

The hierarchical edge bundle method clusters the edges of a radial layout to better understand and analyze graphs, but its effectiveness relies critically on the quality of the hierarchical organization of its nodes and edges. This paper proposes a novel graph visualization approach that extracts the community structure of a network and organizes it into a more balanced and meaningful hierarchy...

This paper proposes a computational model for visual perception: the visual pathway is considered as a functional process of dimensionality reduction for input data, that is, to search for the intrinsic dimensionality of natural scene images. This model is hierarchically constructed, and final leads to the formation of a low-dimensional space called perceptual manifold. Further analysis of the ...

In this paper, we introduce a new agglomerative clustering algorithm in which eadl pal.tcIIi duster is represented by a collection of fmzy hyperboxes. Initially, a number of such hyperboxes arc calculated to represent the pattern samples. Then, the algorithm applies multi-resolution techniqlle.'i to progressively "combine~ these hyperboxes in a hierarchial manner. Stich an agglomerative scheme ...

Detection of natural boundaries is a fundamental problem in computer vision but evaluation of boundary detection performance has tended to concentrate on images with low scene complexity. Importantly, recent boundary detection analysis [7] shows that performance on scenes with higher scene complexity is low. However, work in [6] has shown that for datasets with some scene consistency [1] it is ...

This study identifies relationship among socio-economic and environmental factors with life expectancy in Africa. Socio-economic indicators were collected from international databases for 46 African countries. In this study, correlation coefficient were used to be ablo determine linear relationships between paired socio-economic variables. And also, regression analysis used for identification o...

An optimized three-lead ECG hierarchial decision-tree type of classification system for myocpardial infarction is presented. For selection of the best threshold values for each criterion and the best association of features, we developed a procedure based on "receiver operating characteristic" (ROC) curve data analysis and information theory. Optimization was obtained through maximization of in...