Mohammad Malkawi

Analysis of a graph coloring based distributed load balancing algorithm

Abstract We present the analysis of a distributed load balancing algorithm based on edge coloring of undirected graphs. One version (linear version) can be studied directly using linear system theory. We show that the performance of another version (integer version), which is more realistic in that the loads are integers, can be studied as a perturbation of the linear version. Both versions of our algorithm converge to stable behavior for arbitrary topologies. In the case of the binary n -cube processor network we prove that after n steps of the integer version, for any initial load distribution, each processor has a load not more than n /2 away from the average.

Analysis of failure and recovery rates in a wireless telecommunications system

We derive estimates of mean time to failure and mean time to recover/repair for both hardware and software in a large wireless telecommunications system, based on six months of manually recorded outage data. The observed failure and recovery distributions are not consistent with simple exponential processes. The data can be described by Weibull or two-stage hyper-exponential distributed processes. The duration distributions for scheduled and unscheduled software outages have very different characteristics. The complex distributions observed may be the composition of simple independent processes which cannot be separated in this data set due to a lack of adequately detailed information or proper characterization of outage causes. In this system we found a coverage of /spl sim/98% for autorecovery from unscheduled software failures with an autorepair fraction of /spl sim/36%.

A biometric-secure e-voting system for election processes

In this paper we propose a multifaceted online e-voting system. The proposed system is capable of handling electronic ballots with multiple scopes at the same time, e.g., presidential, municipal, parliamentary, amongst others. The system caters for integrity of an election process in terms of the functional and non-functional requirements. The functional requirements embedded in the design of the proposed system warrant well-secured identification and authentication processes for the voter through the use of combined simple biometrics. The design of the system guarantees that no votes in favor of a given candidate are lost, due to improper tallying of the voting counts, with the proper incorporation of system FLAGpsilas. Transparency of voting follows through in all phases of an election process to assure the voter that his/her vote went in favor of his/her candidate of choice. Besides its main functional properties, the proposed system is designed to cater for several essential nonfunctional requirements. Of utmost importance are the requirements for correctness, robustness, coherence, consistency, and security. To verify the robustness and reliability of the proposed system, intensive computer simulations were run under varying voting environments, viz. voter density, voter inter-arrival times, introduced acts of malice, etc. Results of the simulations show that security and performance of the system are according to expectations. These results provide the proper grounds that would guide the decision maker in customizing the proposed system to fit his particular voting needs.

A secure novel sensor fusion architecture for nuclear applications

We propose a novel architecture to fuse and synthesize data from multiple sensors. This architecture, based on wireless communication of data, can be applied to monitor system integrity, to help in system control, and for personnel guidance through potentially hazardous radiation areas in nuclear applications. The proposed architecture employs sensor fusion in a way that would lead to improved decision making. The sensor suites used are interconnected serially to warrant more robust sensing strategies while leveraging spatially correlated data. They are also fed in parallel into a data fusion center using wireless technologies to ensure enhanced system reliability. While the proposed architecture can readily be tailored for specific applications in the nuclear industry such as for plant monitoring and automated decision and control, it is also designed to track and guide personnel away from radiation-contaminated zones.

A security-embedded infrastructure for Tele-Traffic Speed Control

Abstract In this paper we introduce a novel approach, relying on intelligent engineering, whereby the maximum speed limit at which vehicles on the road can cruise is controlled from some central or distributed facility. The system, as designed, leverages the use of the ubiquitous cellular infrastructure to cut down the costs involved that would otherwise accrue as a result of the need to build a dedicated traffic control system. In the new system maximum speed limits are transmitted from a Central Control Facility (CCF) to all stretches of roads and highways dispersed across urban areas in a highly dynamic manner. The system uses information arriving via a dynamic feedback system on prevailing weather conditions, road conditions, and bulk of traffic, amongst others, before it would broadcast maximum speed limit information to various destinations. When deployed in its final release, this will be done using a highly automated system with little human intervention. The work presented in this paper elaborates the TTC Network Design and RSU Network Distribution for the Tele-Traffic Speed Control System, to remotely manage, enforce, and control the maximum speed limit allowed on road stretches in rural and urban areas for different vehicle categories. The new system has been deployed successfully in a laboratory controlled environment on three vehicle categories; one category representing passenger vehicles, another buses and commuter transport, while the third representing trucks and freight traffic. It is expected that when the system is fully deployed on the wireless infrastructure, speed-related traffic accidents will witness a drop by more than 65–70% according to known accident statistics.

Artificial neuro fuzzy logic system for detecting human emotions

This paper presents an adaptive neuro/fuzzy system which can be trained to detect the current human emotions from a set of measured responses. Six models are built using different types of input/output membership functions and trained by different kinds of input arrays. The models are compared based on their ability to train with lowest error values. Many factors impact the error values such as input/output membership functions, the training data arrays, and the number of epochs required to train the model.

Productivity and scalability challenges in nano-scale technology

This paper presents the challenges posed by the advancements in technology, specially in the field of nano-technology. The main challenges are within the scope of productivity and scalability. Productivity requires the utilization of high performance and high productivity systems and programming models with global view. Scalability requires the use of programming models with high level of abstraction such as the unified parallel C (UPC) and coarray Fortran (CAF).

A graph-coloring-based navigational algorithm for personnel safety in nuclear applications

In this paper, we propose a navigational algorithm that fuses and synthesizes data from multiple sensors. This algorithm, based on graph coloring theory and wireless communication of data, can be applied for personnel guidance through potentially hazardous radiation areas at nuclear facilities. The proposed algorithm relies upon coloring of the links (paths) involved in a way that would lead to rapid convergence of the edges within a graph, which, in turn, leads to improved navigational guidance of occupational workers alongside paths of minimum radiation. Verification of algorithm functionality is done via MATLAB simulations while considering the case of a radiation leak following a given accident scenario. Furthermore we test the robustness of the supporting network infrastructure using OPNET under proposed design layout.