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排序方式: 共有350条查询结果,搜索用时 14 毫秒
61.
This study applies fuzzy sets to integrate the supply chain network of an edible vegetable oils manufacturer. The proposed fuzzy multi-objective linear programming model attempts to simultaneously minimize the total transportation costs. The first part of the total transportation costs is between suppliers and silos; and rest one is between manufacturer and warehouses. The approach incorporates all operating realities and actual flow patterns at production/distribution network with reference to demands of warehouses, capacities of tin and pet packaging lines. The model has been formulated as a multi objective linear programming model where data are modeled by triangular fuzzy numbers. Finally, the developed fuzzy model is applied for the case study, compiled the results and discussed. 相似文献
62.
研究如何将任意有限域上的多项式集分解为有限多个简单列.为了解决这一问题,首先研究简单列和根理想之间的关系,然后基于已有的正则分解算法和有限域上理想的根的两种计算方法设计一个有限域上多项式集的简单分解算法.计算试验表明,文章给出的算法是有效的. 相似文献
63.
64.
《Journal of Coordination Chemistry》2012,65(22):3998-4004
A new solution method for the preparation of a triangular W(IV) cluster starting from an octahedral W(II) cluster is reported. The product Cs3Na2[W3Se4(CN)9]?·?0.5Et4NBr?·?5H2O (1) has been synthesized by boiling W6Br12 in an aqueous solution of Na2Se x , followed by filtering off the dark solid which was then heated with an aqueous solution of NaCN and crystallized by the addition of CsBr and Et4NBr. The compound was characterized by IR, UV-Vis, elemental analysis, and single crystal X-ray diffraction. The described W(II)-to-W(IV) conversion in solution is reported for the first time. 相似文献
65.
Bernard Bialecki Zhongben Wang 《Numerical Methods for Partial Differential Equations》2012,28(6):1817-1839
We consider the modified nodal cubic spline collocation method for a general, variable coefficient, second order partial differential equation in the unit square with the solution subject to the homogeneous Dirichlet boundary conditions. The bicubic spline approximate solution satisfies both the Dirichlet boundary conditions and a perturbed partial differential equation at the nodes of a uniform partition of the square. We prove existence and uniqueness of the approximate solution and derive an optimal fourth order maximum norm error bound. The resulting linear system is solved efficiently by a preconditioned iterative method. Numerical results confirm the expected convergence rates. © 2011 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 2011 相似文献
66.
Xavier Dahan 《Journal of Complexity》2012,28(1):109-135
We give bit-size estimates for the coefficients appearing in triangular sets describing positive-dimensional algebraic sets defined over Q. These estimates are worst case upper bounds; they depend only on the degree and height of the underlying algebraic sets. We illustrate the use of these results in the context of a modular algorithm.This extends the results by the first and the last author, which were confined to the case of dimension 0. Our strategy is to get back to dimension 0 by evaluation and interpolation techniques. Even though the main tool (height theory) remains the same, new difficulties arise to control the growth of the coefficients during the interpolation process. 相似文献
67.
Z. Wei V.S. Deshpande K.P. Dharmasena H.N.G. Wadley R.K. Elzey Y. Chen K. Kiddy 《Journal of the mechanics and physics of solids》2008,56(5):2074-2091
The responses of metallic plates and sandwich panels to localized impulse are examined by using a dynamic plate test protocol supported by simulations. The fidelity of the simulation approach is assessed by comparing predictions of the deformations of a strong-honeycomb-core panel with measurements. The response is interpreted by comparing and contrasting the deformations with those experienced by the same sandwich panel (and an equivalent solid plate) subjected to a planar impulse. Comparisons based on the center point displacement reveal the following paradox. The honeycomb panel is superior to a solid plate when subjected to a planar impulse, but inferior when localized. The insights gained from an interpretation of these results are used to demonstrate that a new design with a doubly-corrugated soft core outperforms solid plates both for planar and localized impulses. 相似文献
68.
激光三角法测量原理可有效应用于三维曲面的非接触精密测量,测量数据的统计处理结果直接关系到测量精度的提高,同时也与测量系统结构、被测物体特性及环境条件等因素有关。从激光三角法的测量机理出发,针对易拉罐罐盖开启口压痕残余厚度测量中影响测量的关键问题进行分析和研究,包括激光光点尺寸、激光散斑、精细结构、被测物体表面的光泽、颜色等,其中前三个问题对测量精度的影响最为突出,通过理论分析和研究,初步给出了计算机仿真和实验结果,探讨了减小或消除测量误差的方法。 相似文献
69.
70.
针对LFMCW雷达中高速加速运动目标的检测问题,该文提出一种二次混频DPT处理方法。利用三角线性调频信号的调频对称性,采用上、下调频差拍信号二次混频的方法消除目标高速运动导致的跨距离单元走动现象。按距离单元进行的DPT处理可获得目标加速度和初始速度的估计。进一步重点研究了多目标存在时的参数估计问题。分析了多目标交叉项的特点,得出了一次交叉项形成有效干扰以及二次交叉项出现的条件。借助于Clean算法的思想,通过依次检测并剔除能量最强目标,有效解决了多目标参数估计问题。给出了多目标处理的主要步骤。仿真结果验证了该文方法及结论的有效性。 相似文献