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区域创新系统外生结构性风险的识别及其解耦分析 总被引:1,自引:0,他引:1
基于对区域创新系统(RIS)的理论回顾,指出了忽视RIS的外生性风险管理是部分地区区域创新系统衰退的重要原因.提出了区域创新系统外生结构性风险的概念和因素构成,给出了各要素之间的耦合关系,基于管理熵进一步构建了该耦合关系的量化描述模型,为区域创新系统外生结构性风险管理走向实用化奠定了基础. 相似文献
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产业集群竞争力的形成机制分析 总被引:7,自引:0,他引:7
基于产业集群的特性和相关理论,分别从内源形成机制和外源形成机制的角度,剖析了产业集群竞争力形成和强化的驱动因素,旨在为提升产业集群竞争力提供理论指导. 相似文献
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产权、制度与公平竞赛--解读"假球黑哨" 总被引:11,自引:0,他引:11
王相林 《北京体育大学学报》2004,27(6):730-732
中国足球职业联赛近年来屡屡爆出假球黑哨的丑闻或遭强烈质疑,令球迷和关心足球发展的各界人士痛惜不已.从产权和制度的角度去认识这个问题,认为:西方职业联赛中,各私有俱乐部本着追求长期利益的动机而进行的是长期重复博弈,重复博弈使得公平竞赛自我维持.而中国大多数职业俱乐部是国有资产,国有产权不可避免使俱乐部具有短期行为和维权意识弱等特点,这使得公平竞赛制度在中国联赛内部能内在维持,只能借助产生于政府的外在权威力量--中国足协来强制干预.但由于中国足协经常不能受到委托人有效的监督,足协在维护联赛公平竞赛的过程中也因而是经常缺位的,这使得外在的中国职业联赛公平竞赛制度也经常失效. 相似文献
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Temporal variation of dynamical modal properties of a base-isolated building is investigated using earthquake records in the building. A batch processing least-squares estimation method is applied to segment-wise time-series data. To construct an input-output system, an auto-regressive model with exogenous input (ARX) of second-order including a forgetting coefficient as a weighting coefficient is used for the estimation of modal parameters. The fundamental and second natural frequencies and the damping ratios of the fundamental and second natural modes of the base-isolated building are identified in the time domain. The identified results are consistent with the results obtained from the micro-tremor vibration data, forced-vibration test data and earthquake records in the present base-isolated building in the case of taking into account the amplitude-dependency of the iso- lators and viscous dampers. It is finally pointed out that several factors, e.g., amplitude dependency of the isolator and damper system and special characteristics of the series-type viscous damper system, may be related complicatedly with the temporal variation in modal properties of the above-mentioned system. 相似文献
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INTRODUCTION In 1998 gastrointestinal pathologists reached aconsensus on the definition of chronic atrophic gas- tritis (CAG), which was described as programmed loss of gastric gland and/or replacement by intestinal glands in gastric mucosa. CAG was recognized to be closely related with development of gastric cancer and listed as precancerous lesions in this meeting (Genta, 1998). According to Correa (1992)’s cascade of gas-tric carcinogenesis, gastric cancer was believed to develop fr… 相似文献
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Ronald Hoggan 《Interchange》1997,28(2-3):183-189
Systemic and paradigmatic problems inherent in science instruction are a genuine threat to our health, and that of future generations. By examining the discoveries of two unsung heroes of 20th century medical science, and the poor acceptance of their dietary interventions in disease processes, we have sufficient evidence to incite a careful re-evaluation and alteration of the methods with which we teach science, and, in fact, all subject areas in our schools and postsecondary institutions. F.C. Dohan and W. Dicke each discovered answers to pathologies through dietary exclusion of gluten. Neither has enjoyed the just fruits of their labours. 相似文献
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HUO Hai-bo ZHU Xin-jian TU Heng-yong 《浙江大学学报(A卷英文版)》2007,8(12):1921-1927
This paper presents an application of iterative learning control (ILC) technique to the voltage control of solid oxide fuel cell (SOFC) stack. To meet the demands of the control system design, an autoregressive model with exogenous input (ARX) is established. Firstly, by regulating the variation of the hydrogen flow rate proportional to that of the current, the fuel utilization of the SOFC is kept within its admissible range. Then, based on the ARX model, three kinds of ILC controllers, i.e. P-, PI- and PD-type are designed to keep the voltage at a desired level. Simulation results demonstrate the potential of the ARX model applied to the control of the SOFC, and prove the excellence of the ILC controllers for the voltage control of the SOFC. 相似文献
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目的为探讨P_(53)、PCNA抗原在胃粘膜中的表达情况及其与胃癌发生的关系方法:应用LsAB免疫织化方法对80例胃粘膜进行了检测结果显了胃癌中P_(53)、PCNA强阳性表达率(80%、93.3%)明显高于异型增生(467%,53.3%)异型增生中P_(53)、PCNA强阳性表达率明显高于慢性萎缩性胃炎及慢性浅表性胃炎.结论研究结果表明,检测P_(53)、PCNA在肖粘膜中的不同表达,对胃癌发生机理的认识有重要意义. 相似文献
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采用文献资料、逻辑分析法对健身气功的调心途径进行研究,认为:调心在"三调"中起主导作用; 由直觉体悟得出调心的过程可分为"外天下"、"外物"、"外生"三个阶段,分别经过寡欲、"抱一"、涵养道德三条层层深入的途径,来实现调心的目的和结果. 相似文献