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1.
We show the close connection between apparently different Galois theories for comodules introduced recently in [J. Gomez-Torrecillas and J. Vercruysse, Comatrix corings and Galois Comodules over firm rings, Algebr. Represent. Theory, 10 (2007), 271 306] and [Wisbauer, On Galois comodules, Comm. Algebra 34 (2006), 2683-2711]. Furthermore we study equivalences between categories of comodules over a coring and modules over a firm ring. We show that these equivalences are related to Galois theory for comodules.  相似文献   
2.
Effects of pollution restrictions on dynamic investment policy of a firm   总被引:1,自引:0,他引:1  
The purpose of this paper is to determine the effects of different pollution standards on the firm's resource allocation decisions. To do so, a dynamic model of the firm is developed in which it is assumed that production causes pollution as an inevitable byproduct. Concerning its investment policy, we suppose that the firm can choose between investing in productive capital goods and investing in abatement efforts.It is shown that, in some cases, future abatement expenses have a negative impact on the present level of productive investment, even if the pollution standard is not binding at the moment. This implies a really dynamic optimal investment policy for the firm, which cannot be obtained within a comparative static analysis.This research has been made possible by a fellowship of the Royal Netherlands Academy of Arts and Sciences. Comments by Frank van der Duyn Schouten and Piet Verheyen (Tilburg University) and by Raymond Gradus (Dutch Ministry of Finance, The Hague) are gratefully acknowledged.  相似文献   
3.
欧阳智  苏秦 《运筹与管理》2021,30(10):220-226
基于企业的关系视角,讨论了企业选择知识流程外包的可能动机。具体而言,在控制服务成本差的背景下,考虑企业间协同合作产生的关系租金与知识传递的信息粘性对企业选择外包策略进行分析。区别于传统基于服务成本差的外包策略,结论指出由于存在信息粘性的影响,服务提供商仅仅具有较高信息处理能力是不能保证企业选择外包。同时指出,即使当服务提供商不具有任何成本优势,基于合作战略的高关系租金也能成为企业选择知识流程外包的又一动机。通过将成本优势和关系优势进行比较,我们指出两类优势对于企业的外包绩效具有互补性,对于企业进行知识流程外包的决策具有替代性。  相似文献   
4.
In [2] the subconstruct of sober approach spaces was introduced and it was shown to be a reflective subconstruct of the category of approach spaces. The main result of this paper states that moreover is firmly -reflective in for the class of epimorphic embeddings. ‘Firm -reflective’ is a notion introduced in [3] by G.C.L. Brümmer and E. Giuli and is inspired by the exemplary behaviour of the usual completion in the category of Hausdorff uniform spaces with uniformly continuous maps. It means that is -reflective in and that the reflector is such that belongs to if and only if is an isomorphism. Firm -reflectiveness implies uniqueness of completion in the sense that whenever is a map with and sober, the associated is an isomorphism. Our result generalizes the fact that in the category the subconstruct of sober topological spaces is firmly reflective for the class of b-dense embeddings in . Also firmness in some other subconstructs of will be easily obtained.A. Gerlo and C. Van Olmen are research assistants at the Fund of Scientific Research Vlaanderen (FWO). E. Vandersmissen is a research assistant supported by the FWO-grant G.0244.05.  相似文献   
5.
关健  闫研 《运筹与管理》2018,27(7):58-67
基于期权博弈理论,以超竞争环境为研究背景,在多个主并企业合作的情形下,建立目标企业存在财务困境的并购模型,得出主并方的最优并购时机;并进行数值模拟分析,重点分析了代表超竞争特点的三个变量(竞争强度、竞争不确定性、企业价值损失因子)、主并企业联盟中参与者的重要程度及联盟中发生机会主义的概率、企业困境因子这六个变量对并购阈值的影响。  相似文献   
6.
Shuqi Xu 《中国物理 B》2021,30(12):120517-120517
Recent studies in complexity science have uncovered temporal regularities in the dynamics of impact along scientific and other creative careers, but they did not extend the obtained insights to firms. In this paper, we show that firms' technological impact patterns cannot be captured by the state-of-the-art dynamical models for the evolution of scientists' research impact, such as the Q model. Therefore, we propose a time-varying returns model which integrates the empirically-observed relation between patent order and technological impact into the Q model. The proposed model can reproduce the timing pattern of firms' highest-impact patents accurately. Our results shed light on modeling the differences behind the impact dynamics of researchers and firms.  相似文献   
7.
研究分析了商业模式创新对财务绩效的影响以及这种影响的环境条件。研究提出了6个理论假设,并采用来自151个新兴技术企业的样本进行了实证检验。研究发现效率型和新颖型商业模式创新都能促进财务绩效。市场不成熟和不正当竞争会加强效率型商业模式创新对财务绩效的促进作用,而不正当竞争会削弱新颖型商业模式创新对财务绩效的促进作用。  相似文献   
8.
In a supply chain logistics system, the function of an intermediary firm is to purchase products and to sell those purchased products to the public or to other firms. This article investigates how an intermediary firm can optimally determine the purchasing cycle length of a deteriorating product. By incorporating the special structure of the intermediary firm’s environments and the deteriorating nature of the product, the inventory problem encountered by the intermediary firm is mathematically formulated. The optimal purchasing cycle length is derived such that the total profit is maximized. Several interesting properties of the optimal policy are investigated and an efficient iterative algorithm is provided to search for the optimal policy. Also, the convergence of the iterative algorithm developed in this paper is proved. Finally, a numerical example is provided to illustrate the features of the proposed problem and the iterative search algorithm.  相似文献   
9.
10.
We present a general model of a network of interacting individuals, each of whom derives a known, real-valued benefit from each possible dyadic interaction. The model views interactions as knowledge-transfer exchanges that add value to the organization. We use this model to derive interaction patterns within an organization. We assume that the value of dyadic interaction benefits is distributed as a randomly permuted geometric series. Moreover, interactions only add value when a large enough waiting period is observed between interaction attempts. We show that an organization optimized for knowledge transfer has a distribution of interaction frequencies which correlates well with observations. Organizations of differing sizes can have similar optimal structures as long they have similar normalized levels of interdependence between interactions, and distribution of interaction benefit values. This research has implications for the design of communication infrastructure in a growing organization, as well as for the predictive value of modeling organizations at different scales.  相似文献   
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