Establishing complete and reliable coverage for a long time-span is a crucial issue in densely surveillance wireless sensor networks (WSNs). Many scheduling algorithms have been proposed to model the problem as a maximum disjoint set covers (DSC) problem. The goal of DSC based algorithms is to schedule sensors into several disjoint subsets. One subset is assigned to be active, whereas, all remaining subsets are set to sleep. An extension to the maximum disjoint set covers problem has also been addressed in literature to allow for more advance sensors to adjust their sensing range. The problem, then, is extended to finding maximum number of overlapped set covers. Unlike all related works which concern with the disc sensing model, the contribution of this paper is to reformulate the maximum overlapped set covers problem to handle the probabilistic sensing model. The problem is addressed as a multi-objective optimization (MOO) problem and the well-known decomposition based multi-objective evolutionary algorithm (MOEA/D) is adopted to solve the stated problem. A Multi-layer MOEA/D is suggested, wherein each layer yields a distinct set cover. Performance evaluations in terms of total number of set covers, total residual energy, and coverage reliability are reported through extensive simulations. The main aspect of the results reveals that the network's lifetime (i.e. total number of set covers) can be extended by increasing number of sensors. On the other hand, the coverage reliability can be increased by increasing sensing ranges but at the expense of decreasing the network's lifetime.
2D Electrical Resistivity has been applied at three selecting areas within the study area using Dipole-dipole and Wenner arrays with an a-spacing of 1 m, and the profile length was 120 m for both. The total data points were 4455 reads for Dipole-dipole, and the total data points for Wenner were 2340 reads, and the depth of each array was 15.4 m and 20.2 m, respectively. The 2D inverse results indicate the resistivity anomalies approximately at depth (2 - 7.8) m formed as a weakness zone lies within the quaternary and Injana Formation deposits and interbedded with secondary gypsum and gypcretes. Additionally, the inverse resistivity distribution model demonstrated that the area is impacted by groundwater that is interaction wit
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Abstract:
The issues related to foreign trade is a broad field for discussions and captures the interest of economists for their contribution to the process of economic development in the economies of the countries, especially developing ones. The imports of goods and services in foreign trade constitute an important part of the local by which the economy gets goods and services that the economy cannot produce because of the incompetent base of production. Further, the demand function of imports occupied a good deal of the attention of researchers in the field of international economics for which agricultural imports constitute an important part. The reason for the interest in the subject is due to its im
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Abstract---The aim of the current research is to identify the level of logical reasoning skills in chemistry students at the Faculty of Education for Pure Sciences/ Ibn Al-Haytham for the academic year (2021-2022). The differences in their level of skills according to the gender variable (males and females) and the academic stages (first- second - third - fourth). The descriptive approach was adopted because it corresponds to the nature of the research objectives. The research sample consisted of (400 )students selected in a relatively random stratified way. The researcher constructed a logical reasoning test, which includes (6) sub-skills , which is (proportional - probabilistic- synthetic- deductive- logic- variable adjustment). The psych
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This study aimed at investigating the effect of using computer in
Efficiency of Training Programme of Science Teachers in Ajloun District in
Jordan.
1- What is the effect of using computer in program for the two groups
2- ( the experimental and control group ) .
3- Are there any statistics different in the effect of using computer
program for the two groups ?
4- Are there any statistics (comparison ) or different of the effect of the
effect of using computer program refer to the sex (male or female )?
The community of the study consisted of all the science student in
educational directorate of Ajloun district for the academic year 2009 –
2010, they are (120) ( male and female) . The sample of the study<
BMMAM Saleh, EUROPEAN ACADEMIC RESEARCH, 2016
The wide use of lead compounds as an engine anti-knock reflects conversely on all components of the ecosystem. This study aimed to detect the concentration of lead in various types of gasoline and gas oil that are highly consumed by vehicles. Eight fuel samples were collected from different feul stations distributed in different districts of Baghdad city. These included two gas oil (diesel) stations and three stations for each type of gasoline (leaded and unleaded). Lead was extracted by the modified chemical method, and then flame atomic absorption technique was applied to assay its concentrations. The results indicated that lead levels were within permitted limits (150 mg Lead L-1) recommended by the
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