Message form the Editors  

 Internet and the Arab World: Understanding the Key Issues and Overcoming the Barriers

Wasfi Alrawabdeh
Kent Business School, University of Kent, UK

Abstract: The evolution of the Internet is affecting many nations around the world and forcing changes to business and socio-economic development plans. It has major implications for the realization of the concept of globalization. The Arab world as developing countries with an economy in transition, has been investing in building its communications infrastructure and adopting the use of the Internet since 1995 as a vital tool for development. This paper will provide a deeper understanding of the key issues surrounding the Internet use in the Arab world with a focus on the challenges faced that relate to a number of social, technological, financial and legal issues. There are a number of suggested solutions and recommendations having to do with collaboration between the governments and the private sectors in each country and between the specialized institutions within the Arabian countries to diffuse the use of the Internet in the Arab world.

Keywords: Internet, infrastructure, barriers, digital divide, Arab world

A New Allocation Technique for Methods and Attributes in Distributed Object-Oriented Databases Using Genetic Algorithms

Abstract: With the wide increase in using distributed object-oriented databases, it became important to find an  efficient technique to store large-scale databases on the different sites. The allocation of object-oriented database involves allocation of both methods and attributes within the classes. The main objective of this paper is to introduce a new technique for allocating the distributed object-oriented database methods and attributes among N sites. The proposed technique uses genetic algorithm to find the best allocation (optimal or near optimal) of the object-oriented database methods and attributes to the available sites. A cost function that computes the total data transfer during the execution of queries is developed. The genetic algorithm steps use this cost function to evaluate the possible allocations of methods. Validation of the proposed technique is done via simulation. The experimental results of the proposed technique depict that it has a great impact in reducing the total time required to find the best allocation and in most of the cases it reaches the optimal allocation of the methods.

Keywords: Object-oriented database, allocation, methods, attributes, genetic algorithm, distributed database.

Received November 19, 2006; accepted June 17, 2007

Implementation of a Hybrid Voice Control
System for a Colony of Robots

Abstract: In this paper, a voice command system for autonomous robots is proposed as a project. The methodology adopted is based on hybrid techniques used in speech recognition which are zero crossing and extremes with dynamic time warping followed by a decision system based on independent methods test results. To implement the approach on a real time application, a personal computer interface was designed to control the movement of a set of robots by simple voice commands. The voice command system for four autonomous robots is designed. The main parts of the robots are a microcontroller from Microchip PIC16F84 and a radio frequency receiver module. 

Keywords:

Speech recognition, voice command, hybrid methods, DTW, robots, microcontroller

 Received January 27, 2007; accepted October 30, 2007

 Hardware Implementation Low Power
 High Speed FFT Core

Muniandi Kannan and Srinivasa Srivatsa
Department of Electronics Engineering, Chennai, India

Abstract: In recent times, DSP algorithms have received increased attention due to rapid advancements in multimedia computing and high-speed wired and wireless communications. In response to these advances, the search for novel implementations of arithmetic-intensive circuitry has intensified. For the portability requirement in telecommunication systems, there is a need for low power hardware implementation of fast fourier transforms algorithm. This paper proposes the hardware implementation of low power multiplier-less radix-4 single–path delay commutator pipelined fast fourier transform processor architecture of sizes 16, 64 and 256 points.  The multiplier-less architecture uses common sub-expression sharing to replace complex multiplications with simpler shift and add operations.  By combining a new commutator architecture and low power butterfly architecture with this approach power reduction is achieved. When compared with a conventional fast fourier transform architecture based on non-booth coded wallace tree multiplier the power reduction in this implementation is 44% and 60% for 64-point and 16-point radix-4 fast fourier transforms respectively. The power dissipation is estimated using cadence RTL compiler.  The operating frequencies are 166 MHz and 200 MHz, for 64 point and 16 point fast fourier transforms, respectively. Our implementation of the 256 point FFT architecture consumes 153 mw for an operating speed of 125 MHz. 

Keywords: Pipelined architecture, shift register, finite state machine, common sub-expression, multiplier-less architecture.

 

Filtering Spam E-Mail from Mixed Arabic and English Messages: A Comparison of Machine Learning Techniques

Abstract: Spam is one of the main problems in emails communications. As the volume of non-english language spam increases, little work is done in this area. For example, in Arab world users receive spam written mostly in arabic, english or mixed Arabic and english. To filter this kind of messages, this research applied several machine learning techniques. Many researchers have used machine learning techniques to filter spam email messages. This study compared six supervised machine learning classifiers which are maximum entropy, decision trees, artificial neural nets, naïve bayes, support system machines and k-nearest neighbor. The experiments suggested that words in Arabic messages should be stemmed before applying classifier. In addition, in most cases, experiments showed that classifiers using feature selection techniques can achieve comparable or better performance than filters do not used them.

Keywords: Anti-spam filtering, machine learning techniques, text data mining.

 Received July 21, 2007; accepted October 23, 2007

 Implementation of Contextual Clustering Method for Statistical Parametric Maps in Functional Magnetic Resonance Images

Senthamarai Kannan1 and C. Vijayalakshmi2
1Department of Statistics, Manonmaniam Sundaranar University, India
2Department of Mathematics, Sathyabama University, India

Abstract: A contextual clustering procedure for Statistical Parametric Maps is calculated from time varying three-dimensional images. The algorithm can be used for the detection of neural activations from functional Magnetic Resonance Images. Ogawa et al. (1990) have discussed about the brain magnetic resonance imaging with contrast dependent on blood oxygenation concepts. Subsequently, the processing strategies for time-course data sets in functional magnetic resonance imaging of the human brain have been analyzed by Bandettini et al. (1993). By using the voxel by voxel testing technique, the neighborhood information is utilized and this is achieved by using a Markov random field prior concept and Iterated Conditional Modes algorithm. The simulation results and human functional magnetic resonance imaging experiments using visual stimulation demonstrate that a better sensitivity is achieved with a given specifications in comparison with the voxel-by-voxel thresholding technique.  

Keywords: Brain imaging, structural anatomy, auditory signal processing, statistical parametric mapping functional magnetic resonance images, fMRI.

 

A Delphi Study on Issues for Successful Information Technology Transfer in the
Arab World

Abstract:

Adoption of enabling technology is one beneficial and significant way countries can improve their developmental progress and achieve higher living standards. Many complex issues are involved in the consideration of information technology transfer.  Some of those issues are not completely defined and studied, or cannot be precisely measured. Thus, a Delphi study was conducted in this research to investigate, identify and prioritise major issues for successful information technology transfer in developing countries from the perceptions of stakeholder groups in the Arab World. Responses were elicited from information technology academics, information technology practitioners, government officials and information technology suppliers. Valid questionnaires were returned from 73 respondents in the first round survey, providing a net response rate of 61% and yielded 410 perceived issues. Through two rounds of the Delphi survey, these issues have been synthesised and categorised into 10 major issue categories with 71 sub-issues. This study aims to assist in understanding the major issues surrounding information technology transfer success in the Arab World and to better realise the benefits of information technology transfer.

Keywords:

Information technology transfer, major issues, Delphi study, Arab world.

 Received January 23, 2007; accepted June 16, 2007

A Comparative Study in Wavelets, Curvelets
 and Contourlets as Feature Sets for
Pattern Recognition

Abstract: There have been a number of recent works in computer vision that had used new age multiresolution multidirectional transforms  like curvelets and contourlets for face and character recognition. Although these works produced high recognition accuracies they did not provide any comparative study against more well known techniques and hence could not justify the use of these new transforms as against more traditional methods. In this work we will compare the recognition accuracies of the aforesaid two transforms against a very well known multiresolution transform viz. the wavelet transform. this study aims at showing the research community how good or how bad the aforesaid transforms are when compared against wavelets as a feature set for pattern recognition.

 Keywords: Curvelet, contourlet, face recognition, character recognition.

Received July 1, 2007; accepted October 23, 2007

 Analysis and Parameter Extraction of P
Wave Using Correlation Method

Mohamed Ben Messaoud, Besma Khelil, and Abdennaceur Kachouri
Laboratory of Electronic and Information Technology, National School of Engineers of Sfax, Tunisia

Abstract: The objective of this paper is to develop an efficient P wave detection algorithm based on the morphology characteristics of arrhythmias using correlation and regression in ECG signal. Subjects for experiments included normal subjects, patients with atrial fibrillation, ventricular tachycardia, and patients with change of the artifactuale amplitude. After the step of the detection of R peak using the pan- tompkins algorithm, the correlation and regression were utilized to calculate the similarity factors between a studied P wave and the reference one. The correlation coefficient can indicate the kind of arrhythmia diseases. The algorithm was tested using MIT-BIH arrhythmia database where every P wave was classified. The results are presented in terms of correlation coefficient. Then some parameters have been extracted in order to classify the arrhythmias. The correlation coefficient results of the system are 1,0.07 and –0.92 for normal beats, atrial fibrillation and change of the artifactuale amplitude, respectively. The extracted parameters are closely similar to the expert values given by the cardiologist.  The results reveal that the system is accurate and efficient to detect and classify arrhythmias resulted from atrial fibrillation or change of the artifactuale amplitude. 

Keywords: ECG, P wave detection, correlation, regression, diagnosis.

New Algorithms to Minimize Handoff
 Latency in AMTree Protocol

Abstract:

In active networks, programs can be injected to network elements (routers/switches). This allows programmers to enhance existing protocols or deploy new protocols. AMTree protocol is an active network based protocol that makes sending packets to receivers, after source migration, an efficient process. In AMTree protocol, after source migration, handoff latency computed from the time of reconnecting to a new base station until finding nearest core to the mobile source. In this paper we present two new algorithms to minimize the handoff latency in AMTree protocol. We show that handoff latency is much lower than that of AMTree handoff algorithm if the mobile source connects to a base station which is subscribed to the multicast group. Also we show that our algorithm gets better results than AMTree if the new base station is not in the multicast group.

Keywords: Active networks, mobile networks, multicast, handoff.

Received May 26, 2007; accepted October 30, 2007

 Impact of the Angular Spread and Antenna
Spacing on the Capacity of Correlated
 MIMO Fading Channels

Mohammed Abdo Saeed , Borhanuddin Mohd Ali , Sabira Khatun , and Mahamod Ismail
 Faculty of Engineering, Universiti Putra Malaysia, Malaysia
 Faculty of Engineering, Universiti Kebangsaan Malaysia, Malaysia

Abstract: It has been shown that the capacity of a multiple-input multiple-output system increases linearly with the number of antennas, provided that the environment is rich scattering. However, this increase in the capacity is substantially degraded if the multiple input multiple output channels are correlated. In this paper, the capacity of correlated multiple input multiple output fading channel is investigated for laplacian and uniform angular energy distributions that implicitly represent two different scatterer distributions. The effect of the spatial correlation of a uniform circular antenna array is considered. Optimal power allocation is implemented to maximize the capacity. Through extensive Monte Carlo simulations, the results show that multiple input multiple output channel capacity is a function of the angle spread and antenna spacing. These two parameters play a major role in dictating the spatial correlation which in turn affects on the capacity. Large angle spread leads to lower correlation between the antenna elements and consequently higher capacity. The degradation in the capacity can be reduced by increasing the spacing between the antenna elements.    

Keywords: MIMO systems, capacity, correlation, scattering distributions.

  

Knowledge-Based Modeling Approach for Performance Measurement of Parallel Systems

Abstract:

Parallel systems are important computing platforms because they offer tremendous potential to solve inherently parallel and computation intensive applications. Performance is always a key consideration in determining the success of such systems. Evaluating and analyzing parallel system is difficult due to the complex interaction between application characteristics and architectural features. Traditional performance methodologies like experimental measurement, theoretical/analytical modeling and simulation naturally apply to the performance evaluation of parallel systems. Experimental measurement uses real or synthetic workloads, usually known as benchmarks, to evaluate and analyze their performance on actual hardware. Theoretical/analytical models try to abstract details of a parallel system. Simulation and other performance monitoring/visualization tools are extremely popular because they can capture the dynamic nature of the interaction between applications and architectures. Each of them has several types. For example, experimental measurement has software, hardware, and hybrid. Theoretical/analytical modeling has queueing network, petri net, etc. and simulation has discrete event, trace/execution driven, Monte Carlo. All of them have their own advantages and disadvantages. The first part of this paper will concentrate on identifying parameters for carrying out a comparative survey on these techniques and second part will justify the need for some kind of modelling approach which combines the advantages of all the three performance evaluation techniques and lastly paper will be focusing on an integrated model combining all the three techniques and using knowledge-based systems to evaluate the performance of parallel systems. This paper also discusses certain issues like selecting an appropriate metric for evaluating parallel systems; need to select proper workload and workload characterization.

Keywords: Knowledge-based system, integrated modelling, metrics, parallel systems, performance evaluation.

 Received May 4, 2007; accepted October 16, 2007

A New Approach Using Temporal Radial Basis Function in Chronological Series

Abstract:In this paper, we present an extended form of the radial basis function network called temporal- radial basis function network. This extended network is used in decision rules and classification in spatio-temporal domain applications like speech recognition, economic fluctuations, seismic measurements and robotics applications. We found that such a network complies, with a relative ease, to constraints such as capacity of universal approximation, sensibility of node, local generalisation in receptive field, etc. For an optimal solution based on a probabilistic approach with a minimum of complexity, we developped two temporal radial basis function models. Application to the problem of Mackey-Glass time series, it has revealed that temporal radial basis function models are very promising, compared to traditional networks.

Keywords: Temporal RBF, classification, spatio-temporal, speech recognition, robotics applications.

 Received August 9, 2007; accepted Novembre 5, 2007

Language Based Information Routing
Security: Policy Enforcement

Abstract:

Languages-based security promises to be a powerful tool with which provably secure routing applications may be developed. Programs written in these languages enforce a strong policy of non-interference, which ensures that high-security data will not be observable on low-security channels. The information routing security proposed aim to fill the gap between representation and enforcement by implementing and integrating the divers security services needed by policy. Policy is enforced by the run-time compiler and executions based mechanism to information violating routing policy and regulation of security services. Checking the routing requirements of explicit route achieves this result for statements involving explicit route. Unfortunately, such classification is often expressed as an operation within a given program, rather than as part of a policy, making reasoning about the security implications of a policy more difficult. We formalize our approach for a C++ like language and prove a modified form of our non-interference method. We have implemented our approach as an extension to C and provide some of our experience using it to build a secure information routing.

Keywords:Security policy, routing, condition statements

 Received January 5, 2007; accepted November 6, 2007

New Approach for Conception and Implementation of Object Oriented Expert System Using UML

Abstract: Since conception is the primary part in the realization of a computer system and in order to help designers describe their software, several languages and tools such the UML modelling language have been proposed in the literature. UML knew an important success for the conception of object oriented systems. In this paper, we propose a new approach of conception and implementation of object oriented expert system based on the UML. For this we introduce our approach of design of the object oriented expert system based on UML, then we define an extension of the CLIPS, called VCLIPS_UML, in order to support UML.  VCLIPS_UML brings two main improvements to CLIPS. The first improvement permits an easy access and modification of the CLIPS knowledge base. The user introduces his knowledge base described with the UML class and the object diagram; VCLIPS_UML gives the corresponding script directly. The second improvement concerns the ease of its utilization by making the syntactic and semantics aspects of the CLIPS programming language more transparent. The implementation of VCLIPS_UML is carried out in a way to make it expandable and portable.

Keywords: Expert system, expert system shell, UML, object oriented programming and GUI.

 Received March 16, 2007; accepted June 15, 2007