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81.
We use the BBGKY hierarchy and the mass, momentum, and intrinsic energy conservation laws, which are consequences of this hierarchy, to obtain the hydrodynamic equations for multicomponent systems and the diffusion equations. We formulate several restrictions on the thermodynamic equations for irreversible processes. 相似文献
82.
Amitava Datta 《Pramana》1993,40(6):L503-L509
It is argued with the help of an illustrative model, that the inter species hierarchy among the fermion masses and the quark
mixing angles can be accommodated naturally in the standard model with (approximate) flavor democracy provided there are three
exactly massless neutrinos and four families of sequential quark-leptons with all members of the fourth family having roughly
equal masses. The special problem of light neutrino masses (if any) and possible solutions are also discussed. 相似文献
83.
The concept of super value nodes was established to allow dynamic programming to be performed within the theory of influence diagrams and to reduce the computational complexity in solving problems by means of influence diagrams. This paper is focused on how influence diagrams with super value nodes are affected by the presence of imprecise information. We analyze how to reduce the complexity when evaluating an influence diagram in this framework by modelling these kinds of nodes and random magnitudes in terms of fuzzy random variables. Finally, an applied example of the theoretical results is developed. 相似文献
84.
Data envelopment analysis (DEA) is a mathematical programming technique which has a wide application area. There are many applications of DEA to measure firms’ performance. Balance sheet data is frequently used in order to measure performance of firms through DEA. So it is the characteristic of balance sheets that assets and liabilities amount to the same value. When the data for inputs and outputs are selected from both assets and liabilities sections of the balance sheet, it is important that more attention be paid to the analysis since values assigned to inputs and outputs could be included in assets and liabilities at the same time. Such a situation could create problems concerning the conclusions drawn as a result of analysis. 相似文献
85.
应用最小二乘法准则,并改进了层次分析法判断矩阵的构成,获得考虑专家评价水平的诸影响因素权向量;基于集值统计法和属性数学原理,建立了对高等级公路路线方案量化综合评价优选模型,并给出了计算实例. 相似文献
86.
韩国强 《高校应用数学学报(A辑)》1994,(3)
本文我们讨论了矩形域上带连续边界条件的一类多元散乱数据最优插值。给出了某些情形插值的误差估计,误差估计表明在某些点上还具有超收敛性。 相似文献
87.
S. M. Natanzon 《Functional Analysis and Its Applications》2003,37(1):21-31
We derive formulas making it possible to calculate the Taylor expansion coefficients of the string solution for the Gelfand–Dikii hierarchy. According to the Witten conjecture, these coefficients coincide with the Mumford–Morita–Miller intersection numbers (correlators) of stable cohomology classes for the moduli space of n-spin bundles on Riemann surfaces with punctures. 相似文献
88.
Jean-Sylvestre Gakwaya 《Mathematical Logic Quarterly》1997,43(1):73-77
In his 1953's paper, Grzegorczyk proved that a certain kind of relation classes of Grzegorczyk's hierarchy could be characterized inductively. We give a simpler version of this characterization. 相似文献
89.
90.
Hans Georg Schaathun 《Designs, Codes and Cryptography》2004,31(1):27-42
A greedy 1-subcode is a one-dimensional subcode of minimum (support) weight. A greedy r-subcode is an r-dimensional subcode with minimum support weight under the constraint that it contain a greedy (r - 1)-subcode. The r-th greedy weight e
r is the support weight of a greedy r-subcode. The greedy weights are related to the weight hierarchy. We use recent results on the weight hierarchy of product codes to develop a lower bound on the greedy weights of product codes. 相似文献