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91.
Hideki Sano 《Journal of The Franklin Institute》2003,340(5):293-306
This paper is concerned with boundary control of a linear distributed parameter bioprocess. Huang's result (Ann. Differential Equations 1(1) (1985) 43) on the spectrum determined growth assumption is applied to prove that the closed-loop system becomes exponentially stable under a certain condition with respect to the feedback gain. Moreover, it is shown that the decay rate of the open-loop system is given by letting the feedback gain tend to zero. 相似文献
92.
Our model analyzes the effects of the interplay between environmental degradation and consumption choices on economic growth dynamics and on economic agents’ welfare. We show that if private goods can be consumed as substitutes for environmental goods, then economic growth may be fueled by environmental deterioration. In this context, undesirable economic growth may occur, characterized by an inverse correlation between aggregate capital accumulation and economic agents’ welfare. 相似文献
93.
作为多年来经济总量位居河北省第一位的唐山市,这几年国民经济得到了飞速发展,消费需求总量的逐步扩大在一定程度上对经济增长的拉动起到了举足轻重的作用。本文建立了城乡居民消费水平与唐山经济增长关系的误差修正模型,研究表明唐山城乡居民消费对其经济增长有正向拉动作用,城镇居民消费的拉动作用比农村居民的要大。因而,采取措施缩小城乡居民消费的差距,统筹二者的发展,是唐山完成两个"率先"的目标、建成全面小康社会不得不面对的问题。 相似文献
94.
WTO与农民收入增长研究 总被引:3,自引:0,他引:3
本文通过定性分析和定量计算,找到影响农民收入增长的最重要因素;结合WTO《农业协议》及我国农业资源变化趋势和中国人口实际,提出逐步加大财政支农力度及区别对待;加强农业和农村经济发展的宏观调控,结合各地实际,分类指导;采取灵活的土地承包政策,实现土地规模经营,提高土地的产出率等一系列增加农民收入措施。 相似文献
95.
Externalities as conventionally defined miss many of the spillovers that are both causes and consequences of the technological changes that underlie economic growth. We introduce a much wider concept called technological complementarities. New general purpose technologies (GPTs) rejuvenate the growth process by creating technological complementarities, which are adequately measured neither by total factor productivity (TFP) nor by externalities. There would be major gains from technological change even if the returns on capital invested in innovation never exceeded the returns on investing in existing technologies so that there were neither externalities nor positive changes in TFP. 相似文献
96.
97.
信息技术的成熟和“无纸化”办公的普及使“单轨制”成为可能。在互联网大数据的背景下,“数据保全”理念开始兴起,双轨制的弊端日益显露,单轨制成为电子文件管理的未来趋势。从数据保全角度出发对电子文件从形成前期、运行过程中、归档时到归档后这整个过程进行管控,可以使“单轨制”管理模式更加完善,也可以确保在动态变化的互联网背景下数据信息的保全。 相似文献
98.
Potential growth of two widely-grown hybrid rice varieties in the Jinhua district of Zhejiang Province, Shanyou63 for mid-rice and Xieyou46 for late rice, was simulated using a crop growth model of WOFOST. Parameters of the rice growth in WOFOST were calibrated through field experiments from 1999 to 2002 in Jinhua. The potential yield simulated with WOFOST was about 12 t/ha for Shanyou63 and 10 t/ha for Xieyou46, which are in good agreement with the highest recorded yield obtained in this area. Under farmers practice, current yield is about 7.5 t/ha for Shanyou63 and 6.5 t/ha for Xieyou46. There is a gap between the actual rice yield and the potential yield for these two hybrid rice varieties grown in this area. The attainable target yields were set to 70% to 75% of their potential yields for the two varieties. A recently developed software "Nutrient Decision Support System (NuDSS)" for irrigated rice was used to optimize nutrient management for these two rice varieties. According to NuDSS, the optimal fertilizer N requirement for the target yields was about 150 kg/ha for Shanyou63 and about 120 kg/ha for Xieyou46, which were only about 70% of the fertilizer N application under current farmers' practice. Comparing with farmers' practice, there is great potential to increase actual rice yields and to reduce fertilizer N use rates by improving rice crop management practice in Jinhua. 相似文献
99.
100.
关于营造我国农村新型合作组织良好成长环境的探讨 总被引:2,自引:0,他引:2
目前农村合作组织在我国之所以发展相对落后并且遭遇瓶颈,是多种环境因素共同作用的结果。它们既包含宏观的国家政策、体制、法律等方面的问题,也有组织本身的问题。只有主观上改变农民对农村新型合作组织的认识,客观上优化组织发展的外部环境,健全组织运行的内部机制,才能实现农村新型合作组织快速健康的成长。 相似文献