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21.
We develop a model explaining the consolidation patterns in the agricultural biotechnology industry. Among different consolidation and cooperation mechanisms, we consider collaborative and licensing agreements, joint ventures, acquisitions, and exchanges of ownership and spin-offs. The key results derive from the benefits of coordinated actions, distinction between transferable and nontransferable payoffs, the substitutability, complementarity, and the importance of the managers' noncontractible investments, and access and expansion of markets. Results from the model are used to examine the cooperation and consolidation activities for four major players in the agricultural biotechnology industry, DuPont , Dow Chemical , Monsanto , and Novartis .  相似文献   
22.
论科研选题应注意的几个问题   总被引:5,自引:0,他引:5  
科研选题要善于把握选题的原别和导向,注意课题的研究动态,把握课题的研究范围,发挥出科研人员的优势,设计出切实可行的研究路线。  相似文献   
23.
Operational Research and the environment   总被引:1,自引:1,他引:0  
The discipline of Operational Research (OR) is primarily concerned with improving the effectiveness and efficiency of decision processes. These processes take place everywhere in society: industry, banking, agriculture, government, politics. Frequent use of mathematical optimization models is typical of OR. Since the early '80s these models are increasingly packaged in a user-friendly way, as Decision Support Systems. In the following we will illustrate how OR can be used to describe and solve a number of environmental problems.  相似文献   
24.
当前的养老制度改革是关注的焦点。本文首先将从介绍现存的筹集模式入手,试图换个角度来思考在人口老龄化背景下的我国养老金基金制度,实证分析模式选择对于缴费率等的影响,并基于此,讨论未来改革的方向。  相似文献   
25.
The purpose of this paper is to provide evidence that the debate between quantitative and qualitative is divisive and, hence, counterproductive for advancing the social and behavioral science field. We advocate that all graduate students learn to utilize and to appreciate both quantitative and qualitative research methodologies. As such, students will develop into pragmatist researchers who are able to utilize both quantitative and qualitative techniques when conducting research. We contend that the best way to accomplish this is by eliminating quantitative research methodology and qualitative research methodology courses from curricula and replacing these with research methodology courses at different levels that simultaneously teach both quantitative and qualitative techniques within a mixed methodological framework.An earlier version of this article received the 2003 Southwest Educational Research Association (SERA) Outstanding Paper Award.  相似文献   
26.
27.
We present a probabilistic model based on the one developed by Hernández Mendo and Anguera (Revista de Psicologíca Social, 16(1), 71–93, 2001). Here we have tried to break down the interaction contexts that the opposing teams are able to generate and transform during the game. We are aware that a given player or team does not produce consistent behaviour in similar situations. However, a degree of uncertainty is assumed to exist regarding whether the results obtained are a specific function of the analysis used. In order to carry out this research a category system which optimized that used in the previous model was developed. This system should enable the interaction between teams to be observed within the actual play of a soccer game. A lag sequential analysis was performed on the basis of a coding of the behavioural flow. After describing the behavioural patterns obtained a probabilistic model of the development of play in soccer is proposed.  相似文献   
28.
Land use externalities, open space preservation, and urban sprawl   总被引:4,自引:0,他引:4  
Parcel data on residential land conversion are used to investigate how land use externalities influence the rate of development and modify policies designed to manage urban growth and preserve open space. Several “smart growth” policies are found to significantly influence land conversion, including a development clustering policy that concentrates development and generates preserved open space. In addition to directly affecting a parcel's hazard rate of conversion, this policy is found to affect neighboring parcels' conversion by generating a positive open space externality that hastens their development. The implication that the clustering policy could generate a more sprawled pattern of development is explored using spatial simulation.  相似文献   
29.
工作流和工作流管理系统的合理应用可大大提高办公自动化的程度,而现有的工作流系统在支持工作流基本模式上存在一定的缺陷。一种新出现的YAWL语言较好地支持了工作流现有的基本模式,文章就YAWL语言及其系统的执行方法进行了初步的研究。  相似文献   
30.
周立  熊志坚 《价值工程》2007,26(3):128-131
我国成品油定价机制经历了一个漫长的改革历程,从计划经济下的单一价格发展成为目前的逐渐向国际油价靠拢。文中阐述了每个阶段的特征和影响,并对现行成品油定价机制的特点和不足及未来的改革方向作出了分析。  相似文献   
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