A Novel Clustering Method Based on Quasi-Consensus Motions of Dynamical Multiagent Systems

This paper presents a novel approach for clustering, which is based on quasi-consensus of dynamical linear high-order multiagent systems. The graph topology is associated with a selected multiagent system, with each agent corresponding to one vertex. In order to reveal the cluster structure, the agents belonging to a similar cluster are expected to aggregate together. To establish the theoretical foundation, a necessary and sufficient condition is given to check the achievement of group consensus. Two numerical instances are furnished to illustrate the results of our approach

Road traffic injuries in Rawalpindi city, Pakistan.

Data on road traffic accident (RTA) injuries and their outcome are scarce in Pakistan. This study assessed patterns of RTA injuries reported in Rawalpindi city using standard surveillance methods. All RTA injury patients presenting to emergency departments of 3 tertiary care facilities from July 2007 to June 2008 were included. RTA injuries (n = 19 828) accounted for 31.7% of all injuries. Among children aged 0-14 years females suffered twice as many RTA injuries as males (21.3% versus 11.4%), whereas this trend reversed for the age group 15-24 years (41.9% versus 21.7%). One-fifth of injuries were either fractures or concussion. Severity and outcome of injuries were worse for the age group 45 years and older. For every road traffic death in Rawalpindi city, 29 more people were hospitalized and 177 more received emergency department care. These results suggest the need for better RTA injury surveillance to identify preventive and control measures for the increasingly high road disease burden in this city

The epidemiology of stroke In a developing country (Pakistan)

Ischemic stroke is a major cause of neurological morbidity and mortality. The objective of this review article is to summarize facts pertaining to acute ischemic stroke and its various aspects in a developing country like Pakistan, where resources are limited and the healthcare system is underdeveloped. No large-scale epidemiological studies are available to determine the true incidence of stroke in Pakistan. We conducted a study to determine the prevalence of several important stroke risk factors among Pakistani stroke patients, and to determine whether these risk factors differ among urban versus rural populations. We also used existing data from literature to compare overall stroke incidence in Pakistan to that in developed countries. In this study we found that for stroke besides hypertension, prolonged contraceptive use and pregnancy are additional risk factors in Pakistan. Which is more prevalent in urban populations than rural population? Developed countries except Germany have much lower stroke incidences than Pakistan

FUZZY AGGREGATING FUNCTIONS FOR MULTIOBJECTIVE VLSI PLACEMENT

When fuzzy logic is used with multi-objective optimization, min/max operators may not be desirable. This is primarily due to lack of compensation/submission of min/max. To overcome this, Ordered Weighted Averaging (OWA) operators were proposed by yager. OWA requires the selection of a control parameter (beta) which is different for different problem instances. In this work we propose new fuzzy aggregating fucntions that simulate the fuzzy AND/OR logic, and have the advantages of OWA without a need of any control paramter. Comparison with OWA for the VLSI cell placement using Simulated Evolution produced encouraging results

FAST FUZZY FORCE-DIRECTED/SIMULATED EVOLUTION METAHEURISTIC FOR MULTIOBJECTIVE VLSI CELL PLACEMENT

VLSI standard cell placement is the process of arranging circuit components (modules) on a silicon layout. The cell placement problem is a proven NP hard combinatorial optimization problem. The complexity of this problem increases when multiple optimization objectives are considered simultaneously. In this paper, a novel technique is presented to address this hard problem, while optimizing multiple objectives. A major difculty with such multi-objective combinatorial optimization problems is the existence of a very large solution search space, one of which is the desired optimal solution. Simulated Evolution (SE) a general iterative heuristic is used to traverse the large search space, while fuzzy logic is resorted to assist in multi-criteria decision making and overcome the imprecise nature of design information at placement stage. New fuzzy aggregation functions are proposed. SE is hybridized with force directed algorithm to speed-up the search. The proposed schemes are compared with previously presented SE based heuristics. The implementations exhibit considerable improvement in terms of both solution quality and runtime