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81.
This article deals with the evaluation of pressure drop and consumption of energy for a steady-state solvent extraction in a horizontal pulsed sieve-plate column, which are important for the design and optimization of the periodic-flow processes for industrial applications. In this study, the pressure drop and the position of loading points are investigated. Moreover, a mathematical evaluation on the energy consumption in the case of a pulsed flow is conducted, and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and plate-free area is investigated as well. The results of this study are helpful for optimization of column geometry targeted to higher performance and lower energy consumption. 相似文献
82.
83.
Laser surface nitriding of Ti–6Al–4V alloy was carried out with a Nd:YAG pulsed laser. The microstructure and corrosion behaviour of the nitrided samples were examined, using SEM, XRD, XPS, and anodic polarization tests in 2 M HCl solution. Laser nitriding produced a thin continuous TiN layer followed by TiN dendrites and TiN0.3 needles. The laser nitrided specimen exhibited less corrosion current density, passivated more readily and also, maintained a lower current density over the duration of the experiment. This was correlated with the formation of very thin, continuous TiNxOy film, which could retard chloride ions ingress into the substrate. 相似文献
84.
A major concern in designing communication systems is to maintain quality of service for a wide range of channel conditions. This is an important issue particularly for the applications where precise characterization of the channel is impossible. For such applications, the source data can be classified into several classes and Unequal Error Protection (UEP) can be used to effectively protect the more important classes even in poor receiving conditions. This paper is focused on the study, design, and performance evaluation of unequal error protecting turbo coded modulation schemes. We first propose several schemes for unequal error protecting using turbo coded modulation. All these schemes provide high performance gains for more important classes that can hardly be achieved using conventional coded modulation schemes. We then study unequal error protecting turbo coded modulation schemes by deriving channel capacity and cutoff rates for different protection levels. We show that for more important classes more room is available for improvement. 相似文献
85.
M. Seyed Salehi S. Serajzadeh 《Journal of Materials Engineering and Performance》2009,18(9):1209-1217
A thermo-mechanical model has been developed to establish a coupled heat conduction and plastic flow analysis in hot-rolling
process. This model is capable of predicting temperature, strain, and strain rate distributions during hot rolling as well
as the subsequent static recrystallization fraction and grain size changes after hot deformation. Finite element and neural
network models are coupled to assess recrystallization kinetics after hot rolling. A new algorithm has been suggested to create
differential data sets to train the neural network. The model is then used to predict histories of various deformation variables
and recrystallization kinetics in hot rolling of AA5083. Comparison between the theoretical and the experimental data shows
the validity of the model. 相似文献
86.
Interleaver design for turbo codes 总被引:6,自引:0,他引:6
Sadjadpour H.R. Sloane N.J.A. Salehi M. Nebe G. 《Selected Areas in Communications, IEEE Journal on》2001,19(5):831-837
The performance of a turbo code with short block length depends critically on the interleaver design. There are two major criteria in the design of an interleaver: the distance spectrum of the code and the correlation between the information input data and the soft output of each decoder corresponding to its parity bits. This paper describes a new interleaver design for turbo codes with short block length based on these two criteria. A deterministic interleaver suitable for turbo codes is also described. Simulation results compare the new interleaver design to different existing interleavers 相似文献
87.
Surveyed 198 parents of 8–17 yr old children to determine how parents' beliefs about injury prevention influenced their preventive efforts. A health belief model helped predict parent-reported teaching of safety skills and preventive environmental interventions. The variables most associated with parental preventive endeavors were the belief that intervention can avoid injury, a realistically high appraisal of the amount of time involved, and feelings of high knowledge and competence to teach safety skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
89.
Since electricity demand is increasing continuously, it is necessary to invest in expansion of distribution network capacity. From the asset management point of view, it is necessary to encourage the private sector to invest in distribution network. To do this, distribution network managers must provide important opportunities for private sector to profit from their investments. One of the options for private sector is to invest on distributed generations (DGs). In this regard, distribution company (DisCo) must sign power purchase agreement (PPA) with DG owners (DGOs). So, optimal siting, sizing and PPA rates from economic point of view are important challenges which are considered as the main contribution of this paper. The proposed methodology of this paper applies load and price uncertainties into the planning problem. The proposed scheme involves using non-dominated sorting genetic algorithms II (NSGA II), since it attains non-dominated solutions in which DisCo and the DGO can put their personal preferences into practice. To evaluate the effectiveness of the suggested method, the computer simulations are done on a 33-bus distribution network and the results are discussed. 相似文献
90.