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21.
The cost optimization is a key element to determine the least-cost feed mixture according to animals’ nutrient requirements and the effective use of the sources. In this paper, the cost optimization of feeds is performed by genetic algorithm, considering the growing style and type, age, nutritional requirement and feedstuff costs for poultry and different types of animals. The proposed method is compared with linear programming approach to measure its performance. The obtained results show that Genetic algorithms could be applicable to the cost optimization of the feed mixtures. In addition, a software program is developed by using Delphi environment, which provides flexible, extensible and user-friendly framework for tuning the heuristic relevant parameters and improving the solution quality.  相似文献   
22.
To improve the driving performance of the electric vehicles, batteries or ultracapacitors (UCs) are frequently preferred in the energizing systems. In hybrid structures with multiple supply sources, an energy management system (EMS) is needed to improve the system efficiency, and to provide the optimum power sharing between a battery and a UC. The purpose of this study is to investigate the effectiveness of the Jaya optimization method for the urban use of the EMS of an ultralight electric vehicle powered by battery/UC. The performance of the proposed method is compared with dynamic programming (DP) that is one of the global optimization methods and particle swarm optimization (PSO) that is one of the other heuristic methods for real-time applications. The simulation results show that Jaya-EMS approached 3.1% to the DP, which yields the optimum result with respect to the total energy loss. In addition, the proposed method yields a loss of less than 1.9% from the PSO-EMS. If all the above situations are considered, the proposed EMS method has less lossy alternative solution for the real-time applications.  相似文献   
23.
Universal Access in the Information Society - Blind people are confronting a number of challenges in performing activities of daily life such as reading labels on a product, identification of...  相似文献   
24.
A convenient organic solvent treatment method was developed for the determination of Cd, Cr, Hg, and Pb in polyethylene and polypropylene matrices by energy dispersive X-ray fluorescence spectrometry. The solvent treatment method had many advantages for the fast, simple, and accurate multi-element analysis of these materials. Calibration curves were prepared using organometallic compounds in xylene in the concentration range of 1–80 mg kg?1. The prepared samples had a homogeneous elemental distribution and good durability. The trueness for the quantification of mentioned elements were checked by using a polyethylene certified reference material. The apparent recoveries of the elements with certified values were in the range of 0.81 (Hg) to 1.14 (Pb). The precision was normally better than 8% RSD, with the exception of Hg (10%). The method detection limits were found to be 12, 24, 12, and 12 mg kg?1 for Cd, Cr, Hg, and Pb, respectively. Polyethylene and polypropylene samples were analyzed by both the XRF method and the reference technique for comparative purposes. Application of analysis of variance (ANOVA) showed no differences between the mean results. The proposed method could be also applied to several different xylene soluble plastics.  相似文献   
25.

The residual stress in the vicinity of the deposited region causes failure and excessive deformation of parts fabricated by a DED process. The deposition strategy remarkably affects characteristics of residual stress and deformation of the fabricated part for the case of depositing materials on a thin substrate with a cantilever structure. The goal of this paper is to investigate the effects of deposition strategies on thermo-mechanical characteristics of Inconel 718 deposited region on AISI 1045 substrate with a cantilever structure by a LENS process using finite element analyses. The influence of deposition strategies on temperature and residual stress distributions in the vicinity of the deposited region is examined to obtain appropriate deposition strategies. The effects of appropriate deposition strategies on the deflection and the distortion of the designed model are investigated. Finally, suitable deposition strategies are chosen from the viewpoints of characteristics of residual stress and deformation.

  相似文献   
26.
The inhibiting properties of two synthesized metals (alkyl)-2-hydroxy benzene sulfonate compounds have been studied on the corrosion of steel (St-3) in aerated 0.1N H2SO4 solutions by potentiodynamic polarization (dc) technique and electrochemical impedance spectroscopy (ac). The polarization curves indicate that the inhibitors are mixed-type. The impedance increases with inhibitors concentration. Low difference in inhibition efficiencies of two compounds for the corrosion of St-3 steel could be explained by high similarities of their structures. Results obtained by both electrochemical methods are in relatively good agreement.  相似文献   
27.
Microwave transmission, reflection, and absorption behavior and the shielding effectiveness of electrochemically synthesized polypyrrole films with dc conductivities ranging from 0.001 to 50 S/cm are presented. Results show that the electrical conductivity of the doped polypyrrole films has a significant effect on transmission, reflection, and absorption of microwaves. Heavily doped, conducting films were highly reflective, whereas lightly doped, semiconducting films had very high transmission. Intermediate conductivity polypyrrole samples were highly absorptive. The agreement between experimental data and theoretical modeling provided confidence to extend the modeling to include the effect of sample thickness on the transmission, reflection, and absorption properties of films with a wide range of conductivity values, hence, providing valuable information for the design of microwave devices and fundamental understanding of the material properties. A method of measuring the far-field sheilding effectiveness of polypyrrole films is also presented. Results of shielding experiments indicated the potential for such applications. © 1994 John Wiley & Sons, Inc.  相似文献   
28.
Here is reported the synthesis of o-phenylenediamine functionalized graphite (OPDFG) using the phosphorus trichloride surface modified graphite (PCl3-SMG) and the o-phenylenediamine (OPD). PCl3-SMG was obtained via chlorophosphorylation of graphite for the study. PCl3-SMG and OPDFG were analyzed using ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD) and Scanning Electron Microscope (SEM). UV-Vis analysis shows that OPDFG have higher absorbance than graphite and PCl3-SMG. According to FTIR analysis, PCl3-SMG has –PCl2 functional groups, which shows that PCl3 reacts with sp2 C-H groups on graphite's edge planes during the formation of PCl3-SMG. Synthesis of OPDFG can be explained by a replacement reaction of amine groups of OPD with –PCl2 groups. XRD data show that after modification of graphite with PCl3 and after amine treatment of PCl3-SMG, crystallite sizes of PCl3-SMG and OPDFG decrease. SEM analysis shows that both PCl3-SMG and OPDFG have layered structures similar to graphite.  相似文献   
29.
The effects of pyrrole, anthraquinone‐2‐sulphonic acid (AQSA) and iron(III) chloride (FeCl3) concentrations, reaction time and temperature on the electrical conductivity of polypyrrole (PPy)—coated poly(ethylene terephthalate) (PET) fabrics were investigated. With an increase in both the AQSA and FeCl3 concentrations, resistivity decreased to a point beyond which higher concentrations led to increased surface resistivity. Erosion of the polymer coating, in dynamic synthesis from continual abrasion, manifested as an exponential increase in the resistance of the coated textile substrate. This was not encountered in static synthesis conditions. Temperature affected the degree of surface and bulk polymerisation. The effect of polymerisation temperature on conductivity was negligible. Conductive polymer coating on textiles through chemical polymerisation enabled a smooth coherent film to encase individual fibres, which did not affect the tactile properties of the host substrate. The optimum FeCl3/pyrrole and AQSA FeCl3/pyrrole molar ratios were found to be 2.22 and 0.40 respectively. Copyright © 2003 Society of Chemical Industry  相似文献   
30.
In this study, an external melt ice‐on‐coil thermal storage was studied and tested over various inlet conditions of secondary fluid—glycol solution—flow rate and temperature in charging process. Experiments were conducted to investigate the effect of inlet conditions of secondary fluid and validate the numerical model predictions on ice‐on‐coil thermal energy storage system. The total thermal storage energy and the heat transfer rate in the system were investigated in the range of 10 l min ?1?V??60 l min ?1. A new numerical model based on temperature transforming method for phase change material (PCM) described by Faghri was developed to solve the problem of the system consisting of governing equations for the heat transfer fluid, pipe wall and PCM. Numerical simulations were performed to investigate the effect of working conditions of secondary fluid and these were compared with the experimental results. The numerical results verified with experimental investigation show that the stored energy rises with increasing flow rate a decreasing tendency. It is also observed that the inlet temperature of the fluid has more influence on energy storage quantity than flow rate. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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