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An Efficient Method Based on Genetic Algorithms to Solve Sensor Network Optimization Problem
Ehsan Heidari,Ali Movaghar
International Journal on Applications of Graph Theory in Wireless ad hoc Networks and Sensor Networks , 2011,
Abstract: Minimization of the number of cluster heads in a wireless sensor network is a very important problem toreduce channel contention and to improve the efficiency of the algorithm when executed at the level ofcluster-heads. In this paper, we propose an efficient method based on genetic algorithms (GAs) to solve asensor network optimization problem. Long communication distances between sensors and a sink in asensor network can greatly drain the energy of sensors and reduce the lifetime of a network. By clusteringa sensor network into a number of independent clusters using a GA, we can greatly minimize the totalcommunication distance, thus prolonging the network lifetime. Simulation results show that our algorithmcan quickly find a good solution.
Self-Compacting Concrete Incorporating Micro- and Acrylic Polymer
Ali Heidari,Marzieh Zabihi
Advances in Civil Engineering , 2014, DOI: 10.1155/2014/652362
Abstract: This study examined the effects of using acrylic polymer and micro-SiO2 in self-compacting concrete (SCC). Using these materials in SCC improves the characteristics of the concrete. Self-compacting samples with 1-2% of a polymer and 10% micro-SiO2 were made. In all cases, compressive strength, water absorption, and self-compacting tests were done. The results show that adding acrylic polymer and micro-SiO2 does not have a significant negative effect on the mechanical properties of self-compacting concrete. In addition using these materials leads to improving them. 1. Introduction Concrete is the world’s widely used construction material because of its properties. By increasing the use of engineers, SCC [1–6] was developed in Japan. One of the biggest differences between SCC and usual concrete is their incorporation of materials [7, 8]. SCC is considered to be a concrete that can be placed and compacted with no vibration and segregation [9–12]. Because cement, the most important part of the concrete, is very expensive, using SCC is very economical. Polymer concrete (PC) is a composite material which is formed by combining mineral aggregates or monomers [13]. Because of its high strength properties, rapid setting, and ability to resist a corrosive environment, PC is increasingly being used as an alternate to cement concrete in construction, highway pavements, waste water pipes, and other places. Polymers are mostly incorporated in the concrete mixed as emulsions of polymer in water (latexes), but dry polymer powders or liquid monomers or resins may be used [14]. The nature of microstructural modification and void filling and bridging of cracks that occurs when polymer formulations are incorporated in cement systems is such that polymers change the pore structure [15]. The polymer used in this paper is the polymerization product of acrylic acid. This polymer is based on acrylic resins. It has the ability to mix easily at any mortar and is consistent with a variety of acrylic paints. Micro-SiO2 had been used as an addition to SCC for 10 percent by weight of cement, although the normal proportion is 5 to 15 percent. With an addition of 10 percent, the potential exists for very strong, brittle concrete. High replacement rates will require the use of a high range water reducer. When it is used in concrete, it acts as a filler and as a cementitious material. The small microsilica particles fill spaces between cement particles and between the cement past matrix and aggregate particles. Microsilica also combines with calcium hydroxide to form additional calcium
An Efficient Method Based on Genetic Algorithms to Solve Sensor Network Optimization Problem
Ehsan Heidari,Ali Movaghar
Computer Science , 2011,
Abstract: Minimization of the number of cluster heads in a wireless sensor network is a very important problem to reduce channel contention and to improve the efficiency of the algorithm when executed at the level of cluster-heads. In this paper, we propose an efficient method based on genetic algorithms (GAs) to solve a sensor network optimization problem. Long communication distances between sensors and a sink in a sensor network can greatly drain the energy of sensors and reduce the lifetime of a network. By clustering a sensor network into a number of independent clusters using a GA, we can greatly minimize the total communication distance, thus prolonging the network lifetime. Simulation results show that our algorithm can quickly find a good solution.
Maximally Entangled States in the Hydrogen Molecule: The Role of Spin and Correlation  [PDF]
Mohammad Ali Vesaghi, Mohsen Babamoradi, Mehdi Heidari Saani
Journal of Modern Physics (JMP) , 2011, DOI: 10.4236/jmp.2011.27079
Abstract: Many electron calculations on a simplest realistic two electron system i.e. H2molecule was applied and as the consequence correlation effects was reflected accurately in the wavefunctions of H2. Zanardi’s entanglement measurement, demonstrated that the maximum of entanglement for the ground state happens when U =J and this resolved the controversial conclusion of U = 0 for maximum entanglement. It was shown that the ground and third excited states are maximally entangled. These maximally entangled states and also the minimally entangled states are correlated to their spin’s property. The wavefunctions of the not magnetic (S = 0) ground and excited states explicitly depend on correlation parameters whereas the first excited states which is magnetic (S2 = 2 and Sz≠0) is not entangled. The second excited state is not magnetic but its wavefunction does not depend on correlation parameters therefore it is a moderately entangled state. In any case, by switching on a magnetic field an entangled state with Sz = 0 can be extracted from a not entangled degenerate magnetic state. We suggest that in a realistic molecular scale system, there is two criteria for finding maximally entangled electronic states, first the system should be in moderately correlated regime and second the system should have a non-magnetic (Sz = 0) electronic state.
DNA Methyltransferases Directed Anti-Cancerous Plant Medicine (Xanthomicrol and Galloyl) Based Molecular Docking and Dynamics Simulation  [PDF]
Ehsan Heidari Soureshjani, Ali Kazemi Babaheydari, Elahe Saberi
Computational Molecular Bioscience (CMB) , 2015, DOI: 10.4236/cmb.2015.52003
Abstract: DNA methyltransferases 1 (DNMT1) has been looked as crucial targets against various types of cancers. MD simulations have advanced to a point where the atomic level information of biological macromolecule (protein or DNA-protein or protein-protein) can easily be advantageous to predict the functionality. In this study we utilize xanthomicrol and galloyl compounds to investigate potential compounds for the inhibition of DNMT1, and the results of these two compounds are compared with drug decitabine. Xanthomicrol and galloyl are found to dock successfully within the active site of DNMT1. A comparison of the inhibitory potential of screened xanthomicrol inhibited DNMT1 approximately is identical with those of their corresponding drugs, decitabine. The stability of the DNMT1 with the best docked xanthomicrol, were further analysed in molecular dynamics (MD) simulation and compared with those of the respective drugs namely decitabine which revealed stabilization of these complexes within 300 ns of simulation with better stability of DNMT1.
A comparative study of total quality management of health care system in India and Iran
Ali Heidari Gorji, Jamal A Farooquie
BMC Research Notes , 2011, DOI: 10.1186/1756-0500-4-566
Abstract: Based on the Baldrige health care criteria for performance excellence 2009-2010 and the guidelines proposed by the American Hospitals Association for hospitals in pursuit of excellence, compared health care services in three countries. The data are collected from the capital cities and their nearby places in India and Iran. Using ANOVAs, three groups in quality planning and performance have been compared.Results showed there is significantly difference between groups and in no case the hospitals from India and Iran are found scoring close to the benchmarks. The average scores of Indian and Iranian hospitals on different constructs of the IHCQPM model are compared with the major results achieved by the recipients of the MBNQ award.In no case the hospitals from India and Iran are found scoring close to the benchmarks (Baldrige health care criteria for performance excellence 2009-2010 and the guidelines proposed by the American Hospitals Association for hospitals). These results suggested to health care services more attempt to achieve high quality in management and performance.Good health, responsiveness to the expectations of its people, and financial contribution to the nation are the goals for health care systems of a country [1]. An overview of the health scenario all over the world indicates that despite having numerous excellent health care facilities, there exists a sufficiently large gap between the demand and delivery. In India nearly 1 million people die every year due to inadequate health care and two-third population is deprived of specialist care. The global health observatory [2]. Also reports a per capita expenditure of US$ 215 on health in Iran. There are nine physicians working for every 10, 000 persons in Iran.With increasing competition, advances in medical sciences, and rising patient expectations, the health care systems have become complex organizations. They need to obtain an optimum balance between the resources and patient satisfaction. Total
A Dual-Band Circularly Polarized Stub Loaded Microstrip Patch Antenna for GPS Applications
Abbas Ali Heidari;Mohammad Heyrani;Mansoor Nakhkash
PIER , 2009, DOI: 10.2528/PIER09032401
Abstract: A single-feed low-profile and easy to fabricate circularly polarized microstrip patch antenna has been developed for GPS applications. For dual frequency operation, four slots are etched near edges of the patch and a crossed slot etched in the center for generating circular polarization. In order to reducing the frequency ratio of two frequency bands of the antenna, the patch is loaded by four short circuit microstrip stubs. The paper reports several simulation results that confirm the desired characteristics of the antenna. Using stub loading, the frequency ratio of two bands of the antenna can be, even, reduced to 1.1.
Study Of Managers’ Communication Skills Based On The Staff’s View In Shiraz University Of Medical Sciences
Ali Keshtkaran,Alireza Heidari,Peivand Bastani
Payavard Salamat , 2012,
Abstract: Background and Aim: Since managers' efficiency depends on their communication skills suitable for their employees, this study was conducted to determine such skills among Shiraz University of Medical Sciences (SUMS) managers. Materials and Methods: In this cross-sectional study, 298 SUMS employees working at different departments were selected through simple random sampling technique. The data-collection device was a 21-item questionnaire having 3 parts: verbal skill, effective listening, and feedback communication skills. The data were analyzed using SPSS software. Statistical tests employed included Pearson correlation, T-Test and ANOVA, and the level of significance was determined at 0.05. Results: The respondents' mean age was 32.7 years. Most of them were female, had a bachelor's degree, and worked in logistics department. According to their judgment, their managers had good verbal and effective listening skills, but were average in their feedback. The highest score for communication skills was reported for the students' department and the lowest score for the research department. Older and more experienced employees evaluated their manager's feedback skill (p= 0.001) at a lower level. The statistical test indicated a significant relationship between feedback and level of education (p= 0.001). Conclusion: It seems that the intermediate level of effective listening and feedback skills are due to the managers' lack of sufficient scientific and practical attention to the issue of communication. Therefore, it is recommended that educational workshops be held for managers to make them familiar with the importance of effective communication skills.
Study of optical properties of thin copper films on glass substrate using Kramers-Kronig method
A Morteza Ali,R Maddah,M Heidari
Iranian Journal of Physics Research , 2010,
Abstract: Different thicknesses of 99.97% Cu are deposited on glass substrate by thermal evaporation method at the rate of 2A /sec. Kramers-Kronig method is used for the analysis of the reflectivity constant in the range of 200nm
Cytoprotective Effects of Organosulfur Compounds against Methimazole-Induced Toxicity in Isolated Rat Hepatocytes
Reza Heidari,Hossein Babaei,Mohammad Ali Eghba
Advanced Pharmaceutical Bulletin , 2013, DOI: 10.5681/apb.2013.023
Abstract: Purpose: Methimazole is a drug widely used in hyperthyroidism. However, life-threatening hepatotoxicity has been associated with its clinical use. No protective agent has been found to be effective against methimazole-induced hepatotoxicity yet. Hence, the capacity of organosulfur compounds to protect rat hepatocytes against cytotoxic effects of methimazole and its proposed toxic metabolite, N-methylthiourea was evaluated. Methods: Hepatocytes were prepared by the method of collagenase enzyme perfusion via portal vein. Cells were treated with different concentrations of methimazole, N-methylthiourea, and organosulfur chemicals. Cell death, protein carbonylation, reactive oxygen species formation, lipid peroxidation, and mitochondrial depolarization were assessed as toxicity markers and the role of organosulfurs administration on them was investigated. Results: Methimazole caused a decrease in cellular glutathione content, mitochondrial membrane potential (ΔΨm) collapse, and protein carbonylation. In addition, an increase in reactive oxygen species (ROS) formation and lipid peroxidation was observed. Treating hepatocytes with N-methylthiourea caused a reduction in hepatocytes glutathione reservoirs and an elevation in carbonylated proteins, but no significant ROS formation, lipid peroxidation, or mitochondrial depolarization was observed. N-acetyl cysteine, allylmercaptan, and diallyldisulfide attenuated cell death and prevented ROS formation and lipid peroxidation caused by methimazole. Furthermore, organosulfur compounds diminished methimazole-induced mitochondrial damage and reduced the carbonylated proteins. In addition, these chemicals showed protective effects against cell death and protein carbonylation induced by methimazole metabolite. Conclusion: Organosulfur chemicals extend their protective effects against methimazole-induced toxicity by attenuating oxidative stress caused by this drug and preventing the adverse effects of methimazole and/or its metabolite (s) on subcellular components such as mitochondria.
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