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International Review on Computers and Software - July 2007 - Papers

A Cohabitation Framework for AOSD Models
A Cooperative Framework for Intelligent Decision Support Systems
A Study of Token Based Algorithms for Distributed Mutual Exclusion
A Robust Method for Fingerprint Matching Using Genetic Algorithm
Design of a Fuzzy Controller for pH Using Genetic Algorithm
New Traveling Salesman Problem Approximation Algorithm
Algorithmic Improvements in Pattern Matching
Detection of Lines in Images by Curve Fitting Using Hough Transform
Backward Reachability Analysis Based on BPNs to Model-based Diagnosis with Relationships Among Symptoms
LUT Cascade-Based Architectures for High Productivity Embedded Systems
An Efficient Designated Receiver Signature Scheme
Application Controlled Mobile IP Handoff for 802.11 Wireless Networks
Transferring Data Between Any Two UDDI v3 - Compliant Repositories - K.A.L.I.N.A. Data Migration Tool
Easy and Secure Login by CAPTCHA
Performance/Complexity Analysis of a H264 Video Encoder
Interactive Multimedia E-learning Course for Teachers Education and its Possible Application in Vocational Training
Business Process and Web Services for a B2B Exchange Platform

International Review on Computers and Software - Papers

A Cohabitation Framework for AOSD Models
by A. H. Hannousse, O. Kazar, D. Meslati, Z. Liu

Abstract - In fact, effective assessment of Aspect Oriented Software Development (AOSD) models has been a challenge since the arising of the first aspect-oriented programming languages in the past decade. This paper addresses the assessment problem of AOSD models by introducing a framework where more than one AOSD model can be used for the design and the implementation of the same software system. That proposal makes a possible cohabitation between the AOSD models. In the proposed framework, both Design Patterns and AOSD technologies are connected for achieving the design of software systems. Our idea consists of specifying the patterns satisfying system requirements then applying a software quality assessment process based on adapted object oriented metrics to identify the effective AOSD model for each required pattern. As a result of our model, a software system can be designed using more than one AOSD model which makes the resulting software system more re-usable.

Keywords: Aspect Oriented Software Development, Assessment, Design Patterns, Software Process.

A Cooperative Framework for Intelligent Decision Support Systems

by A. Adla, M. T. Laskri, J. L. Soubie

Abstract - Traditional Decision Support Systems (DSS) have been closed systems and are limited to the data and models contained within the system. In general, the type of support provided is relatively passive because decision makers are expected to scan internal and external data, and find discrepancies and deviations from expectations invoking ad hoc queries and reports that run on operational databases. By endowing the machine of additional capacities to intelligently guide the decision maker in its problem solving process, the system plays a collaborator’s role with the decision-maker.
We propose, in this paper, a Cooperative Framework for Intelligent Decision Support System. The framework embeds expert knowledge within the DSS to provide intelligent decision support, and implements the intelligent DSS using collaboration technologies. This implies a human decision-maker and an automated system sharing dynamically the tasks and jointly working towards a decision. We illustrate the applicability and relevance of this framework through a case study related to crisis management.
Copyright © 2007 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: Decision Process, Decision Support Systems, Intelligent DSS, Cooperative DSS.

A Study of Token Based Algorithms for Distributed Mutual Exclusion
by A. Swaroop, A. K. Singh

Abstract - The selection of a ‘good’ mutual exclusion algorithm, for the design of distributed systems, is of great importance. A number of mutual exclusion algorithms, with different techniques and varying performance characteristics, are available in the literature. These algorithms can be broadly classified into token based algorithms and non-token based algorithms. A number of survey papers for non-token based mutual exclusion algorithms exist. Although, some of them include discussion on token based mutual exclusion algorithms too, however, none of them include any discussion on the newer variants of classic mutual exclusion, like k-mutual exclusion and group mutual exclusion. The paper presents an exhaustive survey of the token based mutual exclusion algorithms. The variants of mutual exclusion problem, namely k-mutual exclusion and group mutual exclusion, have also been covered.

Keywords: Algorithms, Group mutual exclusion, k-mutual exclusion, Mutual exclusion, Token.

A Robust Method for Fingerprint Matching Using Genetic Algorithm
by M. R. Girgis, A. A. Sewisy, R. F. Mansour

Abstract - Fingerprint matching is one of the most important stages in automatic fingerprint identification systems (AFIS). Traditional methods treat this problem as point pattern matching, which is essentially an intractable problem due to the various nonlinear deformations commonly observed in fingerprint images. In this paper, we propose an effective and fast fingerprint matching algorithm based on graph matching principles. And applied genetic algorithms (GA), for matching processing which tries to find the optimal transformation between two different fingerprints. Experimental results demonstrate the robustness of our algorithm to non-linear.

Keywords: Genetic Algorithm; Fingerprint matching; Fitness value; Graph minutiae; Optimization.

Design of a Fuzzy Controller for pH Using Genetic Algorithm

by D. Mokeddem, A. Khellaf

Abstract - The control of pH is important in the chemical industry, poses a difficult problem because of inherent nonlinearities and frequently changing process dynamics. The work described in this paper aims at exploring a technique for producing adaptive fuzzy logic controller (FLC), in which a genetic (GA) is employed to alter membership functions. GA is an adaptive search technique based on natural selection and genetics rules. An adaptive GA-FLC scheme is presented for control of the pH process, the objective is to drive the pH of the solution to the desired set point in the shortest time by adjusting the valves on the two control input streams.

Keywords: Genetic Algorithms, Fuzzy logic, Process control, Nonlinear control, pH.

New Traveling Salesman Problem Approximation Algorithm

by H. F. Kendela, M. A. Al-Ahmar, E.-S. M. El Horbaty

Abstract - The travelling salesman problem (TSP) has been studied by many researchers and a great variety of heuristics and implementations with varying solution quality/running time tradeoffs have been proposed. In this paper, we introduce a heuristic algorithm that uses nearest neighbour heuristic first to find an initial tour and then uses a local search component to improve the quality of the solution. The implementation of our algorithm is given. The local search consists of utilizing a combination of brute force and 2-Optimal techniques on small parts of the tour. The results of our implementation are compared with corresponding results using nearest insertion heuristic on the same instances. The effectiveness of our algorithm derives from the improved tour quality achieved with reasonable running times.

Keywords: 2-Optimal Algorithm, Heuristic Algorithm, Insertion Algorithm, Nearest Neighbour, Travelling Salesman Problem (TSP).

Algorithmic Improvements in Pattern Matching

by L. Dudás

Abstract - This paper shows two algorithmic improvements for pattern matching introducing two new heuristics. For test purposes the author implemented three well-known heuristics to ensure the O(n) worst case time, the O(n log (m) /m) average case time and the O(n/m) best case time of searching for an m length pattern in an n length text that use a  letter alphabet. The first new heuristic predicts the better search direction in the pattern preprocessing phase taking into consideration the unsymmetrical property of the pattern and using it in the search process. This method assumes that the full text resides in the RAM and exploits the fact that the memory reading is not direction dependent. The paper gives the prediction function for uniform character distribution and for natural language text alike and in addition presents a generalized form. The second new heuristic is effective on natural language texts and achieves a longer average jump than the pattern length, making compromise on completeness of search. The method exploits the fact that minimal distances can be determined between occurrences of different substrings for a language by a statistical preprocessing. Tests proved that both heuristics result in fewer jumps and character comparisons in the search phase of the pattern matching.

Keywords: Pattern Matching, Search Direction Prediction, DNA Search, Natural Language Text, Long Jumps.

Detection of Lines in Images by Curve Fitting Using Hough Transform

by A. A. Sewisy

Abstract - This paper a new proposes Algorithm to overcome the drawbacks of the generalized Hough transform, namely its computational complexity and storage requirement. For decreasing the Computation time, the algorithm performs the Hough transform by (1) decomposing an image into small blocks, (2) estimating line parameters through least-squares line fitting for each block, and (3) removing detected lines while performing the Hough transform for the remaining blocks. For reducing the memory storage, the proposed algorithm utilizes a data structure, list to represent accumulators. The method significantly reduces the computational complexity and storage required to evaluate all possible parameters without using a accumulator array. Experimental results are given to show the correctness and effectiveness of the proposed method.

Keywords: hough transforms; line detection; line fitting; segmenting image; accumulator space.

Backward Reachability Analysis Based on BPNs to Model-based Diagnosis with Relationships Among Symptoms
by H. Bennoui, A. Chaoui

Abstract - Diagnosing multiple faults that may occur in distributed systems has received a lot of attention over the last decade. In particular, a backward reachability analysis based on Behavioral Petri Net (BPN) models has been proposed to model-based diagnosis of such systems. Nevertheless, it has been defined without tacking into account the concept of precedence relationships that may exist among fault indications or symptoms. The aim of this paper is two fold: first, to extend such analysis to handle precedence orders among symptoms at their signalization time; and second, to deal with the problem of contradictory observations which conduct to an inconsistency in the given problem. The relationships among symptoms are expressed in the net model as transitions among places denoting the corresponding symptoms. For the diagnosis process, they are captured through a novel set of backward firing rules used to construct the corresponding marking graph. In order to treat the inconsistency problems, we propose to restore the required consistency to the given problem. This is accomplished by identifying some symptoms that are known to be absent in the case under examination and when they are supposed present will explain the observed misbehavior. The paper is written in an informal style emphasizing on considerations of practical order than theoretical ones.

Keywords: Behavioral Petri Nets, Model-based diagnosis, Reachability analysis, Inconsistent marking.

LUT Cascade-Based Architectures for High Productivity Embedded Systems
by V. Dvorak

Abstract - Fast, flexible, cheap in hardware or low-power implementations of multiple-output Boolean functions are often required in embedded systems. The paper describes digital system architectures which embody some of these attributes. They are based on already known, and recently reinvented, representation of combinational logic by Look-Up Table (LUT) cascades. Theoretical background of cascade decomposition is revised and a relation to decision diagrams is pinpointed. The design of LUT cascades is discussed and a heuristic method of cascade synthesis is given. Three possible applications of LUT cascades are presented: combinational logic pipelines, efficient micro-programs with multi-way branching and fast logic simulation in software. It is shown that LUT cascades are quite flexible in making trade-offs between performance and cost by adjusting cascade length, complexity of its cells and multiplicity of cascades. The method of LUT cascades may be quite useful not only for high performance pipelined stream processing or embedded microprocessor or microcontroller firmware, but also in digital system simulation.

Keywords: LUT cascades, binary decision diagrams BDD, MTBDD, iterative disjunctive decomposition, multi-way branching.

An Efficient Designated Receiver Signature Scheme
by M. S. Rababaa, S. J. Aboud, M. A. Al-Fayoumi

Abstract - This article introduces a designated receiver signature scheme which is carrying a characteristic that let the signature to be verified by the cooperation of the signature recipient only. This proposed digital signature scheme is aimed to secure the confidentiality of the signature recipient in many uses since the signed document hold too important data regarding recipient personally. We claim that the proposed scheme is scalable, secure, completely dynamic and more efficient than the already existed schemes.

Keywords: Public key cryptography, digital signature scheme, designated receiver signature scheme.

Application Controlled Mobile IP Handoff for 802.11 Wireless Networks
by G. Singh, A. Pal Singh Atwal, B. S. Sohi

Abstract - IP based IEEE 802.11 wireless networks are ideally suited for providing high data rate connectivity to pedestrian mobile users moving over small geographical areas like airports, university campuses and hotels. Range of 802.11 access points is limited due to technology constraints and replication is required to provide coverage over even small areas. This situation leads to frequent handoffs. In this paper we have proposed and implemented a cross layer approach for providing fast and proactive handoff using Dynamics HUT Mobile IP. This handoff mechanism works on reducing both the layer 2 and layer 3 discovery phases which are major contributors towards the overall handoff latency. Mobile node is made fully equipped with the information about the neighboring access points and mobility agents before the handoff process is executed. Handoff process is totally controlled by a user space application and is proactive in nature. The proposed handoff mechanism reduces the overall handoff delay to less than 250ms. The proposed approach has been tested and evaluated on experimental testbed setup for the purpose. Performance of the handoff approach has been evaluated for VoIP, audio/video streaming and TCP bulk traffic.

Keywords: Dynamics Mobile IP, Handoff, Background scanning, IP networks, VoIP, Skype, Streaming.

Transferring Data Between Any Two UDDI v3 - Compliant Repositories - K.A.L.I.N.A. Data Migration Tool
by A. Mintchev

Abstract - With the discontinuing of the operation of the UDDI Business Registry in January 2006, the focus of UDDI is being moved towards individual enterprise solutions. Whereas each commercial UDDI implementation claim to support the UDDI standard, the interoperability between any two UDDI products of different vendors is zero, in the sense that once having bought a UDDI product of a particular vendor and having published their data into it, the customers could not migrate their existing UDDI solution to that of a new vendor, as neither there exist a tool to transfer the UDDI user data, nor is there a commercial realization of the UDDI v3 replication protocol available, with the help of which the data could be transferred.
This paper introduces a design of a software tool that transfers part or all of the user data from any source UDDI V3 compliant repository into any destination UDDI V3 compliant repository. UDDI entity keys and ownership of UDDI data from the source repository are preserved into the destination repository, whenever this is possible. tModels of checked value sets are transferred as unchecked value sets and values of checked value sets (if any) are not transferred.

Keywords: UDDI, Repositories, Data transfer, import, export, SOAP.

Easy and Secure Login by CAPTCHA
by S. Shirali-Shahreza, M. Shirali-Shahreza, M. T. Manzuri-Shalmani

Abstract - Nowadays, Internet is the center of attention as the integral part of mankind’s contemporary lifestyle. In order to provide the requested services and to conduct the user’s activities in many websites, there is a need to log into the system by user ID and password. Meanwhile, by finding the users’ passwords, hackers log into systems with other users passwords and conduct their illegal activities including withdrawing cash from the user’s account or stealing the user’s data.
This paper provides a new method in order to prevent the entry of hackers into the system with the use of CAPTCHA procedure. In this method, if the password is wrongly entered on a number of occasions, the user’s account gets locked. Thereafter, the computer displays a random word for the user, calling on him to enter it. If the user is able to recognize the word properly, the user’s locked account will be opened. But if the user can not realize the word after several times, the user’s account gets locked for five minutes. With due regard of the weak point of OCR software, only a human user can enter the system and the brute force attacks of the hackers fail. This project has been prepared with the use of PHP language.

Keywords: Brute Force Attack, CAPTCHA (Completely Automated Public Turing test to tell Computer and Humans Apart), Human Computer Interaction, Login System, OCR (Optical Character Recognition).

Performance/Complexity Analysis of a H264 Video Encoder
by H. Krichene, A. C. Ammari, A. Jemai, M. Abid

Abstract - H264/AVC (Advanced Video Codec) is a new video coding standard developed by a joint effort of the ITU-TVCEG and ISO/IEC MPEG. This standard provides higher coding efficiency relative to former standards at the expense of higher computational requirements. For efficient implementation of a H264 video encoder, we propose in this paper a high-level parametric analysis of its computational requirements on a GPP (General Purpose Processor) platform. This analysis is performed on various QCIF and CIF test sequences to evaluate key new features of the standard and to find an optimal balance between the coding efficiency and the implementation cost. The complexity of the obtained optimal configuration outlines the potential of using a multiple processors platform for executing a parallel code version of the H264 reference encoder. For this, profiling the reference code execution is performed to identify the major application bottlenecks and the main subcomponents candidate for efficient parallelization.

Keywords: H264 video encoder, parametric influence analysis, coding performance, implementation complexity, and profiling for task-level parallelization.

Interactive Multimedia E-learning Course for Teachers Education and its Possible Application in Vocational Training
by K. Yordanova

Abstract - In this paper the main characteristics of interactive multimedia systems are described with emphasis on their advantages as tools for knowledge distribution and for effective and high quality professional training. Features of interactivity are discussed and the advantages of interactive multimedia presentations are presented. Two cognitive theories are presented and their application to the development of digital learning materials is demonstrated. General problems related to the development of interactive multimedia digital learning content are discussed and possible solutions are proposed. Tests implemented to evaluate the level of interactivity and quality of developed learning content are described.

Keywords: multimedia, interactivity cognitive theories, outcomes, taxonomies, effectiveness, vocation training, e-learning.

Business Process and Web Services for a B2B Exchange Platform
by Y. Aklouf, H. Drias

Abstract - Web services (WS) and Services Oriented Architecture (SOA) are actually in exponential evolution. They allow systems to communicate with each other using standard Internet technologies. Systems that have to communicate with other systems use communication protocols and the data formats that both systems understand. Such Web Services interest has coincided with the proliferation of XML, Java technology and Business-to-Business (B2B) commerce.
The key attraction of Web Services comes from the business drivers of cost reduction and B2B integration. The B2B standards try to formalise the Business Collaboration (BC) based on documents exchange between partners. This collaboration is defined in some standards in a machine-readable format and in some others it is not. ebXML and RosettaNet specify such a collaboration. This paper compares business processes based on ebXML and RosettaNet with Web service technology. Then, it shows how these standards can be integrated in the same B2B developed architecture.
Copyright © 2007 Praise Worthy Prize S.r.l. - All rights reserved

Keywords: E-commerce, B2B, ebXML, RosettaNet, Business Process, Web Services.