The actual performance of parallel programs is often disappointing, especially in comparison to the peak performance ooered by the underlying hardware. There are many sources of performance degradation and understanding these sources is necessary to improve application performance. In this paper we discuss performance modeling, an approach to understanding the performance of parallel systems. W...

Experimental determination of magnetization characteristics of switched reluctance motors (SRM's) is quite important in their accurate performance prediction. Over the last decade, various experimental procedures have been used to obtain these characteristics. Every evolved new method has its own limitations and constraints. This paper describes an improved, simple and cost effective experiment...

Performance modeling under non-uniform traac is a useful tool to validate simulation accuracy and lend insights to realistic implementation of multihop networks. In this article, we present a performance model capable of tracking non-uniform traac for an arbitrary multihop network. Our model is a an extension of Greenberg-Goodman and Brassil-Cruz models which are limited to Manhattan Street net...

This paper proposes using the genetic algorithms to optimize the PI regulator parameter in the prime mover simulation system. In this paper, we compared the step response characteristics under the conditions of the genetic algorithms and traditional method by MATLAB simulation and field test tested the dynamic characteristics of the prime mover simulation system. The results proved that genetic...

Although Shannon introduced the concept of a rate distortion function in 1948, only in the last decade has the methodology for developing rate distortion function lower bounds for real-world sources been established. However, these recent results have not been fully exploited due to some confusion about how these new rate distortion bounds, once they are obtained, should be interpreted and shou...

NECO is a simple high-performance simulation framework dedicated to the evaluation of Network Coding based protocols. Its main features include (1) definition of graphs representing the topology (which can be randomly generated by NECO or given through a standard representation), (2) the modular specification of network coding protocols, (3) visualization of network operations and seamless stat...

Performance models are presented for affordable parallel processing of images. A generic topology is used for pixel-based processing. A novel parallelization of an image rotation routine is given as a case study.

Roadheaders offer a unique capability and flexibility for the excavation of soft to medium strength rock formations, therefore, are widely used in underground mining and tunneling operations. A critical issue in successful roadheader application is the ability to develop accurate and reliable estimates of machine production capacity and the associated bit costs. This paper presents and discusse...

We analyse the statistical behavior of query-associated quantities in query-logs, namely, the sum and mean of IDF of query terms, otherwise known as query specificity and query mean specificity. We narrow down the possibilities for modeling their distributions to gamma, log-normal, or log-logistic, depending on query length and on whether the sum or the mean is considered. The results have appl...

The current paradigm in student modeling has continued to show the power of its simplifying assumption of knowledge as a binary and monotonically increasing construct, the value of which directly causes the outcome of student answers to questions. Recent efforts have focused on optimizing the prediction accuracy of responses to questions using student models. Incorporating individual student pa...