recently many studies have been done on different issues of using multiple antennas at transmit and receive sides of a radar system in a mimo (multiple input multiple output) configuration. in addition, for the electronic warfare‟s purposes, the utilization of available signals of the environment to detect the targets has gained considerable attention in recent years. such passive radars use th...

In this study, we theoretically investigated Methyl hydrazinecarbodithioate by quantum chemical calculations for geometry optimization, vibration frequencies, and electronic structure parameters. The geometry optimization by DFT, ab initio MP2 method and the frequency calculation by DFT method was performed at the highest available Pople style 6-311G++(3df,3pd) basis set level. The semi-emp...

the imperialist competitive algorithm (ica) that was recently introduced has shown its good performance in optimization problems. this algorithm is inspired by competition mechanism among imperialists and colonies, in contrast to evolutionary algorithms. this paper presents optimization of bead geometry in welding process using of ica. therefore, two case studies from literature are presented t...

phospholipids are important for the biological lipid and are commonly used in biophysical studies.a quantumcalculation for two phospholipids dipalmitoylphosphatidylethanolamine and dipalmitoylphosphatidic acidwere performed using the abinitio software. geometry optimization structures were obtained at rhf level using3-21g, 6-31g*. these basis sets were used to understanding the effects of envir...

intake system design as well as inlet ports and valves configuration is of paramount importance in the optimal performance of internal combustion engines. in the present study, the effect of inlet ports design is investigated on om-457la diesel engine by using a cfd analysis and the avl-fire code as well. a thermodynamic model of the whole engine equipped with a turbocharger and an intercooler ...

wind power has been widely considered in recent years as an available and a clean renewable energy source. the cost of wind energy production is currently the main issue, and increasing the size of wind turbines can reduce wind energy production costs. hence, megawatt wind turbines are being rapidly developed in recent years. in this paper, an aerodynamic analysis of the nrel 5mw turbine is car...

Different methods are available for simultaneous optimization of cross-section, topology and geometry of truss structures. Since the search space for this problem is very large, the probability of falling in local optimum is considerably high. On the other hand, different types of design variables (continuous and discrete) lead to some difficulties in the process of optimization. In this articl...

double bridge girder overhead cranes are used for heavy duty applications in theindustry. in this paper a detailed parametric design optimization of the main girder of box type isperformed for a 150ton capacity and 32m long span crane, after its basic design using availabledesign rules. design optimization is performed using detailed 3d finite element analysis bychanging the number, shape and l...

Geometry optimization is an important part of most quantum chemical calculations. This article surveys methods for optimizing equilibrium geometries, locating transition structures, and following reaction paths. The emphasis is on optimizations using quasi-Newton methods that rely on energy gradients, and the discussion includes Hessian updating, line searches, trust radius, and rational functi...

phospholipids are important for the biological lipid and are commonly used in biophysical studies.A quantumcalculation for two phospholipids Dipalmitoylphosphatidylethanolamine and dipalmitoylphosphatidic acidwere performed using the abinitio software. Geometry optimization structures were obtained at RHF level using3-21G, 6-31G*. These basis sets were used To understanding the effects of envir...