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941.
This paper sets up the construction model of enterprise innovation capacity by analyzing the personal nature, organization, knowledge and market demand. And this paper demonstrates that enterprise innovation capacity should be based on knowledge grasped by personal and organization in the enterprise. Whether the profit can be brought by innovation is mainly decided by competition advantage from innovation capacity. 相似文献
942.
943.
陈小夏 《杭州师范学院学报(社会科学版)》2000,(6):36-42
讨论如何用 Kronecker乘积表示一般实验设计模型 ,包括固定效应模型、随机效应模型及混合效应模型 .讨论如何表平方和为向量的二次型 .从而首次给出了用这些表示去计算平方和的期望值的方法 .本文的结果容易推广到其它实验设计模型 相似文献
944.
First-order phase transitions in finite systems can be defined through the bimodality of the distribution of the order parameter. This definition is equivalent to the one based on the inverted curvature of the thermodynamic potential. Moreover we show that it is in a one-to-one correspondence with the Yang–Lee theorem in the thermodynamic limit. Bimodality is a necessary and sufficient condition for zeroes of the partition sum in the control intensive variable complex plane to be distributed on a line perpendicular to the real axis with a uniform density, scaling like the number of particles. 相似文献
945.
946.
Mathieu Van Vyve 《Mathematical Programming》2006,108(1):53-77
Recently, several authors [8, 10] have argued for the use of extended formulations to tighten production planning models.
In this work we present two linear-programming extended formulations of the constant-capacity lot-sizing problem with backlogging.
The first one applies to the problem with a general cost function and has O(n3) variables and constraints. This improves on the more straightforward O(n4) Florian and Klein [2] type formulation. The second one applies when the costs satisfy the Wagner-Whitin property but it
has O(n2) variables and O(n3) constraints. As a by-product, we positively answer an open question of Miller and Wolsey [4] about the tightness of an extended
formulation for the continuous mixing set.
This text presents research results of the Belgian Program on Interuniversity Poles of Attraction initiated by the Belgian
State, Prime Minister's Office, Science Policy Programming. The research was carried out with financial support of the Growth
Project G1RD-1999-00034 (LISCOS) of the European Community. The scientific responsibility is assumed by the author. 相似文献
947.
Giampio Bracchi Chiara Francalanci 《Computational & Mathematical Organization Theory》1997,3(3):173-198
This paper proposes a formal model of information processing inorganizations. The model takes a process view of organizations and includesboth structural and IS features of processes. Two structural properties areconsidered, networking and parallelism. Information systems are representedin terms of quantity of information used and level of informationcustomization allowed. Process performance is measured in terms of totalinformation processing capacity and flexibility afforded by a process. Therelationship between structural and information system choices and processperformance is studied by simulating the model for a range of values. Thepaper derives a set of propositions describing the independent and combinedimpact of structural and information system choices on performance. The results suggest the predominance of networking over parallelism and ofinformation customization over information quantity in determininginformation processing capacity. They also show a negative effect ofnetworking on process flexibility and an amplifying effect of networking onthe benefits of information customization. Overall, the findings validatethe interdependence between structural and information system variables indetermining process performance. 相似文献
948.
S. R. Nasyrov 《Siberian Mathematical Journal》2008,49(5):894-910
We obtain some estimates for the distortions of the moduli of quadrilaterals, the reduced moduli, and Robin capacities depending on the variation of the boundary of a domain. We show that for sufficiently smooth variations of the boundary the corresponding variations of the moduli and capacities are proportional to the area of the variable part of the domain in some extremal metric. We apply these results to studying the generalized Lavrent’ev problem of finding the shape of an infinitely thin airfoil of given length with the maximal aerodynamical lift under some restriction on the curvature of the airfoil. 相似文献
949.
设素数p≥3,用N(p,c)表示满足同余方程r ̄3+s ̄3≡c(modq)的解数,其中r,s是模p的二次剩余,且0<r,s<p。给出了N(p,c)的渐近公式。 相似文献
950.
实验能力为高等农业院校学生所必备。分析了高等农业院校化学实验教学中存在的问题,从实验内容、教学方法、学生发展、“诚信”意识的培养及实验考核方面提出了改进化学实验教学的基本思路。 相似文献