Spatialized streaming audio in multi-user virtual training environments

Dans cet article, nous décrivons l'ajout d'une communication audio 3D au Virtual Reality Modelling Language (VRML). Celui-ci permet la communication vocale directe entre participants des environnements virtuels d'entraînement. Afin d'obtenir les meilleurs résultats possibles, nous avons étudié divers modèles acoustiques spatiaux et diverses possibilités actuelles du langage VRML. L'adaptation d'un modèle acoustique 3D aux caractéristiques des environnements-cibles d'entraînement médical, ainsi que l'intégration -indépendante de la plateforme utilisée- d'un système de streaming média au langage VRML constituent notre contribution au développement de ces environnements

Packing coloring of generalized Sierpinski graphs

The packing chromatic number $\chi_{\rho}(G)$ of a graph $G$ is the smallest integer $c$ such that the vertex set $V(G)$ can be partitioned into sets $X_1, . . . , X_c$, with the condition that vertices in $X_i$ have pairwise distance greater than $i$. In this paper, we consider the packing chromatic number of several families of Sierpinski-type graphs. We establish the packing chromatic numbers of generalized Sierpinski graphs $S^n_G$ where $G$ is a path or a cycle (with exception of a cycle of length five) as well as a connected graph of order four. Furthermore, we prove that the packing chromatic number in the family of Sierpinski-triangle graphs $ST_4^n$ is bounded from above by 20

Higher-Order Cumulants in System Identification and Signal Decomposition

: The paper surveys the basic concepts of system identification using the higher-order cumulants. Theoretical background for the single 1-D C(q,k) identification formula is described, whereas the simulation results based on it are compared to much more complex and sophisticated polycepstral identification. In the second part, we develop an idea of the superimposed signal decomposition relying upon the multichannel MISO and MIMO models, and the corresponding multichannel system identification via higher-order cumulants. Concluding simulation results confirm the validity of the presented signal decomposition schemes. 1 INTRODUCTION Higher-order statistics based approaches have recently gained wide attention. There are several reasons for that: higher-order statistics have enabled new solutions and improved known ones in the field of the inverse problems, in particular concerning so called blind system identification, they are applicable to the deterministic as well as the stochastic mod..

Packing coloring of generalized Sierpinski graphs

The packing chromatic number $\chi_{\rho}(G)$ of a graph $G$ is the smallestinteger $c$ such that the vertex set $V(G)$ can be partitioned into sets $X_1,. . . , X_c$, with the condition that vertices in $X_i$ have pairwise distancegreater than $i$. In this paper, we consider the packing chromatic number ofseveral families of Sierpinski-type graphs. We establish the packing chromaticnumbers of generalized Sierpinski graphs $S^n_G$ where $G$ is a path or a cycle(with exception of a cycle of length five) as well as a connected graph oforder four. Furthermore, we prove that the packing chromatic number in thefamily of Sierpinski-triangle graphs $ST_4^n$ is bounded from above by 20

Computer-assisted exercise ECG analysis: real-time scheduling within MS-DOS on PCs

Computer analysis and monitoring of the exercise electrocardiograms (ECG) have been advantageously applied for a longer time. Recently, an overwhelming influence of personal computers (PCs) has a visible impact in this field as well. Such PC environment has been used in development of a software package for the on-line exercise ECG analysis. This paper reveals the core of the application, i.e., a built-in real-time executive. A three-phase design approach is described: first, recognition of the tasks and their structure, second, evaluation of the task time complexities, and third, allocation of the tasks and implementation in C++ in the MS-DOS PC environment. Performance of the built real-time multitasking environment is finally studied for the worst-case situation using a prototype PC installation. Keywords: real-time executive, multitasking, on-line exercise ECG analysis, performance evaluation 1 Introduction The exercise ECG [1] has evolved into a diagnostic and therapeutic means ..