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91.
This paper deals with the stability and dissipative problem of a class of stochastic hybrid system. The system under study involves Markovian jump, impulsive effects and time delay, which are often encountered in practice and are the sources of instability. Our attention is focused on analysis of whether the stochastic hybrid system with time-delay is stochastically asymptotically stable and strictly (Q, S, R) dissipative. By introducing an extra artificial time instance, the equivalent system is obtained and the sufficient conditions are derived by using linear matrix inequality (LMI) techniques. The main results of this paper unify the existing results on H∞ control. 相似文献
92.
Marcelo Menezes Morato Manh Quan Nguyen Olivier Sename Luc Dugard 《Journal of The Franklin Institute》2019,356(3):1196-1224
This article is concerned with the control of a Semi-Active suspension system of a 7DOF Full Vehicle model, equipped with four Electro Rheological (ER) dampers, taking into account their incipient dissipativity constraints. Herein, a real-time, fast, advanced control structure is presented within the Model Predictive Control framework for Linear Parameter Varying (LPV) systems. The control algorithm is developed to provide a suitable trade-off between comfort and handling performances of the vehicle in a very limited sampling period (), in view of a possible realtime implementation on a real vehicle. The control structure is tested and compared to other standard fast control approaches. Full nonlinear realistic simulation results illustrate the overall good operation and behaviour of the proposed control approach. 相似文献
93.
Patenting and US academic research in the 20th century: The world before and after Bayh-Dole 总被引:2,自引:0,他引:2
Bhaven N. Sampat 《Research Policy》2006,35(6):772-789
The dramatic growth of patenting and licensing of publicly funded research by American research universities in the closing quarter of the 20th century has stimulated some of the highest-profile debates in science and technology policy today. The issue of what aspects of academic research should be public - and what private - lies at the heart of each of these debates. The movement of academic scientists into commercialisation of discoveries and inventions has been extolled by some as a new model of academic research, one which facilitates economic and social returns from universities. At the same time, this trend has been criticised by others as representing a socially inefficient ‘privatisation’ of academic research and as a threat to the ethos of science itself. This paper places these debates in historical context, with a review of changes in American universities’ patenting policies, procedures and practices throughout the 20th century, an assessment of the logic underlying the passage of the Bayh-Dole Act of 1980, and an overview of its effects on economic returns from university research. 相似文献
94.
我国近年来耕地资源动态变化的区域特征及对策分析 总被引:10,自引:0,他引:10
我国耕地资源的减少已经成为目前面临的主要问题之一,并随着经济的进一步发展,耕地资源减少的现状还将持续下去。本文根据1987-1994年我国耕地面积的总减少、净减少、损失率和变化率分析了耕地动态变化的区域特征,并依次将我国大陆30个省(区)分为不同的类型,提出了不同类(耕地资源、总减少、净 相似文献
95.
我国各地区农村基础教育财政投入的比较分析 总被引:9,自引:0,他引:9
本文对于农村基础教育财政投入进行比较分析。用舒尔兹系数、基尼系数等描述并分析全国各地区农村基础教育的财政投入。从公平和效益两个方面比较客观地评价我国农村基础教育的实际。对于分析结果的经济、社会意义给予一种科学的解决,进而对于国家的财政政策、基础教育政策提出建议,为政府有关部门决策提供有益的参考。 相似文献
96.
97.
本文就科研单位适应市场经济,实现战略转变,总结了实践经验,讨论了几点认识。提出科研单位不能仅以科技成果转让为目标,应加速发展科技产业;不应仅满足于出成果,而应重视并着力于科技成果的转化,才能在社会主义市场经济条件下实现其价值和形成自我积累、自我发展的能力。 相似文献
98.
Marie T. Mora 《Economics of Education Review》1997,16(4):407-418
This study examines the influence of the opportunity costs of school attendance, educational quality attributes, and household socioeconomic status on the educational demand of Mexican Americans, African Americans, and non-Hispanic whites using the 1988–1990 surveys of the National Education Longitudinal Study. Implementing a utility-maximizing framework, educational demand assumes the form of schools' average daily attendance rates and student dropout decisions between the 8th and 10th grades. The basic results suggest that a school's attendance rate is sensitive to educational quality and student characteristics. Moreover, the demand for education measured by student attrition inversely relates to unexplained school attendance, and is positively affected by household socioeconomic status. Some policy recommendations based on the results are discussed. 相似文献
99.
通过对高校学报发表的论文中中文摘要、关键词、英文翻译、中图分类号和参考文献等5个项目执行《CAJ—CD规范》的调查,结果表明:中文摘要和关键词的规范化情况很差,英文翻译、中图分类号和参考文献的规范化情况相对较好,办刊时间较长的本科学报规范化情况比办刊时间较短的本科学报和专科学报好,高校学报整体规范化情况不理想.分析了产生这种现象的原因,并提出改进措施,以提高学报编排的规范化水平. 相似文献
100.
基于C/S模式的企业MIS系统中性能优化的实现 总被引:1,自引:0,他引:1
张青锋 《周口师范学院学报》2004,21(5):86-88
论述了大型数据库应用系统的优化技术和方法.首先提出优化的必要性,然后论述了基于C/S模式的企业MIS系统的几种优化原则和部分优化技术,最后介绍了在开发黄石鑫宝管业有限公司的企业MIS系统的过程中用到的几种优化技术和方法. 相似文献