selective harmonic elimination (she) is a powerful modulation scheme aims to find the required switching angles in order to eliminate the number of undesired harmonics. she is a complicated problem which consists of several nonlinear equations which have multiple local minima. in order to eliminate the higher number of undesired harmonics and as a result reducing the total harmonic distortion (...

this article reports on the findings of a study that investigated the impact of manipulating task performance conditions on listening task performance by learners of english as a foreign language (efl). the study was designed to explore the effects of changing complexity dimensions on listening task performance and to achieve two aims: to see how listening comprehension task performance was aff...

The play-in/play-out approach suggests a new paradigm for system development using scenario-based requirements. It allows the user to develop a high level scenario-based model of the system and directly execute system behavior. The supporting tool, the Play-Engine has been used successfully in several projects and case-studies. As systems developed using this method grow in size and complexity,...

In this paper we define and study Scenario Based P Systems, a model of computation inspired by the metabolic pathways and networks. Starting from the classical definition of P systems with symbol objects and multiset rewriting rules, we define regular expressions able to capture the causal dependencies among different executions of the rules. The results show the computational power of this model.

Like other user-centered approaches, scenario-based design changes the focus of design work from defining system operations (i.e., functional specification) to describing how people will use a system to accomplish work tasks and other activities. However, unlike approaches that consider human behavior and experience through formal analysis and modeling of well-specified tasks, scenario-based de...

A method for scenario based requirements engineering is described. The method uses two types of scenario, structure models of the system context and scripts of system usage. A modelling language is reported for describing scenarios, and heuristics are given to cross check dependencies between scenario models and the requirements specification. Heuristics are grouped into several analytic treatm...

Scenarios have proven useful to elicit, validate and document requirements but cannot be used in isolation. Our concern in this paper is to integrate scenario-based techniques in existing methods. We propose a set of operators to support such an integration. This set is classified in two sub-sets: the one dealing with the integration of the product models of the two initial methods and the one ...