ISSN 1556-6757


SJI 


 

 

 

 

 

 

 

 

 

 
 
 

Volume 1, Issue 1, 2009

 


An Improved Power flow Technique for Distribution Systems
Ashokkumar. R and Aravindhababu. P
 

Abstract


This paper presents an approach of power flow with a view to obtain a reliable convergence in distribution systems. The trigonometric terms are eliminated in the node power expressions and thereby the resulting equations are partially linearised for obtaining better convergence. The proposed method is simpler than existing approaches and solved iteratively similar to Newton-Raphson (NR) technique. This method is applied to two test systems to illustrate its performance. Full Article




Integrating Discovery and Composition of Semantic Web Services Based on Description Logic
Sayed Gholam Hassan Tabatabaei, Wan M. N. Wan Kadir, Suhaimi Ibrahim, and Amir Vahid Dastjerdi

 

Abstract


A problem that has become one of the recent critical issues is automated composition of Web services. A number of approaches have been proposed to resolve the problem. However, discovery and composition of Web services have been neglected by majority of those approaches. In this article, an approach based on Description Logic is proposed. First of all, the architecture of the proposed approach which shows all components of the proposed approach is described. Moreover, a case study is designed to test some components of the proposed approach. The preliminary results of the test demonstrate that the approach provides an efficient solution. Full Article




Using a Machine Learning Approach for Building Natural Language Interfaces for Databases: Application of Advanced Techniques in Inductive Logic Programming   Lappoon R. Tang
 

Abstract

Building a natural language interface for a database has been an interesting task since the 70‟s, which often requires creating a semantic parser. A study on using an advanced inductive logic programming (ILP) approach for semantic parser induction that combines different ILP learners to learn rules for ambiguity resolution is presented. Accuracy of the resulting induced semantic parser can be significantly improved due to the learning of more descriptive rules than those of each individual ILP learner. The task of learning semantic parsers in two different real world domains was attempted and results demonstrated that such an approach is promising. Full Article

 

Low Power Neural Network Training Using A GMDH Type Algorithm
Ankur Agarwal, A. S. Pandya, Morrison S. Obeng
 

Abstract

Authors have developed a Group Method of Data Handling (GMDH) type algorithm for designing multilayered neural networks. The algorithm is general enough that it will accept any number of inputs and any sized training set. Each neuron of the resulting network is a function of two of the inputs to the layer. The equation for each of the neurons is a quadratic polynomial. Several forms of the equation are automatically tested for each neuron to make sure that only the best equation of two inputs is kept. All possible combinations of two inputs to each layer are also tested by the algorithm and only the best neurons at each level are retained. The algorithm’s goal is to create as accurate network as possible while minimizing the size of the network. Software was developed to train and simulate networks using our algorithm. Several applications were modeled using our software, and the results demonstrate that our algorithm succeeded in developing small, accurate and multi-layer networks. This paper further presents the hardware implementation of the algorithm that consumes less power than other such systems. Full Article

 

Implementation of Semantic Bridge: Providing Programmable Access to Distributed Heterogeneous Data   G. M. Prabhu and Prabhakar Balakrishnan
 

Abstract

A recent paper [1] described the design of a system called Semantic Bridge which provides
programmable access to unknown remote data. This paper describes an implementation of that
system in the context of a prototype domain for business process integration. With the use of several standard technologies such as XML, SOAP, Java servlets, and Java connector technologies, Semantic Bridge offers users the ability to write a single program that can run without change on all systems. The results demonstrate a proof of concept for this unique and unprecedented solution for distributed computer systems which can be extended to any domain with information sharing needs. Full Article


 


A New Security Architecture for SIP Based P2P Computer Networks
Huang Yongfeng, Shanyu Tang, Yau Jim Yip
 

Abstract

Many applications are transferred from C/S (Client/Server) mode to P2P (Peer-to-Peer) mode such as VoIP (Voice over IP). This paper presents a new security architecture, i.e. a trustworthy authentication algorithm of peers, for Session Initialize Protocol (SIP) based P2P computer networks. A mechanism for node authentication using a cryptographic primitive called one-way accumulator is proposed to secure the P2P SIP computer networks. It leverages the distributed nature of P2P to allow for distributed resource discovery and rendezvous in a SIP network, thus eliminating (or at least reducing) the need for centralized servers. The distributed node authentication algorithm is established for the P2P SIP computer networks. The corresponding protocol has been implemented in our P2P SIP experiment platform successfully. The performance study has verified the proposed distributed node authentication algorithm for SIP based P2P computer networks. Full Article

 

Ride-Through Topology for Adjustable Speed Drives(ASD’s) During Power System Faults
S.S. Deswal, Ratna Dahiya, D.K. Jain
 

Abstract

Adjustable Speed Drives are susceptible to voltage sags occurring due to faults in electric power system. There are different techniques to enhance ride-through capability of ASD’s during voltage sag conditions. These are aimed at maintaining the DC-link voltage constant by injecting energy from an external source. Ultracapacitors, as storage device, are of reduced size as compared to batteries and provide fast energy exchange.  In this paper, the improved performance of ASD’s with Ultracapacitors at DC- link during various electric power system faults is demonstrated using MATLAB simulation.  Full Article