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51.
52.
采用了一个既能提高立方型状态方程比体积计算精度,又不影响气液平衡条件的简单摩尔修正项来改进PR方程比体积的计算。本文对19种低温流体给出其修正项的值,计算饱和蒸气和液体比体积,并与未修正的PR方程的计算值比较,结果表明这种修正能显著提高低温流体(包括量子流体氢、氦和强极性的氨气)饱和液体比体积的计算精度,并对蒸气比体积的计算也略有改进。 相似文献
53.
We define the hazardous waste management problem as the combined decisions of selecting the disposal method, siting the disposal plants and deciding on the waste flow structure. The hazardous waste management problem has additional requirements depending on the selected disposal method. In this paper we focus on incineration, for which the main additional requirement is to satisfy the air pollution standards imposed by the governmental restrictions. We propose a cost-based mathematical model in which the satisfaction of air pollution standards is also incorporated. We used the Gaussian Plume equation in measuring the air pollution concentrations at population centers. A large-scale implementation of the proposed model within Turkey is provided. 相似文献
54.
将任意差分精细积分法用于三维波动方程地震正演,关键在于如何消除数值计算中有限波场区域边界引起的边界反射。文中采用Berenger给出的电磁波完全匹配层吸收边界条件,推导出三维波动方程任意差分精细积分法地震正演的完全匹配层吸收边界条件计算公式,并给出了完全匹配层吸收边界条件算例。计算结果表明,此方法压制边界反射效果明显。三维波动方程地震正演模拟实例表明,完全匹配层吸收边界条件的任意差分精细积分法为复杂区地震波传播规律研究提供了一种实用的正演模拟工具 相似文献
55.
In this study, distribution and history of residual stresses in plaque-like geometries are simulated based on linear thermoviscoelastic
model, which helps to understand the mechanics and evolution of the residual stresses in the injection molding process. The
numerical calculation of direction, combined with the specified boundary conditions. Results show that the stress variation
across the thickness exhibits a high surface tensile value changing to a compressive peak value close to the surface, with
the core region experiencing a parabolic tensile peak. Residual stress distribution throughout the thickness is almost same
along the flowpath and the final residual stresses value near the gate is lower than the value near the end of flowpath. 相似文献
56.
F-X域粘弹性波动方程保幅偏移 总被引:6,自引:1,他引:5
提出了一种利用粘弹性声波波动方程进行偏移的新方法。其基本思路是,修改成像条件,使修改后的成像方程中考虑振幅补偿,然后利用粘弹性、单程波动方程在F-X域对震源和接收点波场进行延拓,进而完成散射、透射等补偿。理论数据处理和实际地震资料处理表明,该方法理论基础可靠,处理效果明显,能较好地解决实际地质问题。 相似文献
57.
Tokar David M.; Withrow Jason R.; Hall Rosalie J.; Moradi Bonnie 《Canadian Metallurgical Quarterly》2003,50(1):3
Structural equation modeling was used to test theoretically based models in which psychological separation and attachment security variables were related to career indecision and those relations were mediated through vocational self-concept crystallization. In contrast to previous studies, which have found either weak or no support for a relation between separation or attachment security variables and career indecision, results based on a sample of 350 college students indicated that some components of separation and attachment security did relate to career indecision in a theoretically supportable direction. Results also revealed that regardless of whether global or component career indecision measures were used, separation and attachment security effects on indecision were at least partially mediated through vocational self-concept crystallization. The strongest mediated relations were observed for the effects of attachment anxiety and maternal separation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
The purpose of this paper is the modelling of the mechanical behaviour of an elastomeric material, through detailed experimental and numerical procedures, specific to large strains. The experimental technique is based on in-plane kinematics measurements using a speckle extensometer, from which the whole two-dimensional field of in-plane displacements is obtained by a digital image processing [Polymer (2002)]. This part of the work concerns the identification of the constitutive equation for a carbon black natural rubber (NR) vulcanizate. We start by quoting some theoretical considerations relative to rubber elasticity and stress-softening effect, which is the counterpart of the filler reinforcement. Then, we describe the experimental procedure and present data for both non-preconditioned and preconditioned samples. Next, the identification of the constitutive law parameters using a minimization algorithm is driven. Finally, we present the validation of the constitutive model, by its implementation into the finite element code SYSTUS and the numerical simulation of the response of a double edge notched tensile (DENT) specimen. 相似文献
59.
动态规划模型在生产存贮中的应用 总被引:1,自引:0,他引:1
吴明鑫 《陕西科技大学学报》2003,21(5):29-31
利用动态规划模型研究了生产管理中生产存贮问题的数学模型,给出了动态规划的最优性原理和动态规划基本方程,并给出了该数学模型求解的一个实例。 相似文献
60.
Ideal-gas thermodynamic properties for natural-gas applications 总被引:2,自引:0,他引:2
Calculating caloric properties from a thermal equation of state requires information such as isobaric heat capacities in the ideal-gas state as a function of temperature. In this work, values for the parameters of thec
p
0
correlation proposed by Aly and Lee were newly determined for 21 pure gases which are compounds of natural gas mixtures. The values of the parameters were adjusted to selectedc
p
0
data calculated from spectroscopic data for temperatures ranging from 10 to 1000 K. The data sources used are discussed and compared with literature data deduced from theoretic models and caloric measurements. The parameters presented will be applied in a current GERG project for evaluating equations of state (e.g., the AGA 8 equation) for their suitability for calculating caloric properties. 相似文献