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81.
本文以“主体-技术”协同视角来分析战略性新兴产业创新网络形成的内在机理和分类模式。在结合2-模网络理论基础上,从核心技术和创新主体两个维度出发,将战略性新兴产业创新网络分为单核心实验室型、单核心产业链型、单核心辅助型、单核心复合型、多核心实验室型、多核心产业链型、多核心辅助型和多核心复合型。同时,以中国新能源汽车产业为例,通过实证分析发现:除了单核心辅助型和多核心辅助型之外,其它6种模式均存在,并进一步对其创新网络的分类模式及相关特征进行了全面分析。  相似文献   
82.
This paper investigates the effects of crop genetic diversity on farm productivity and production risk in the highlands of Ethiopia. Using a moment-based approach, the analysis uses a stochastic production function capturing mean, variance, and skewness effects. Welfare implications of diversity are evaluated using a certainty equivalent, measured as expected income minus a risk premium (reflecting the cost of risk). We find that the effect of diversity on skewness dominates its effect on variance, meaning that diversity reduces the cost of risk. The analysis also shows that the beneficial effects of diversity become of greater value in degraded land.  相似文献   
83.
民营经济发展的法律环境探析   总被引:2,自引:0,他引:2  
我国的民营经济经历了一个由不合法到合法,从异己再到重要组成部分的曲折过程。民营经济仍面临着产权保护缺位、市场准入门槛过高、融资困难等诸多不利的法律环境与现状。针对这些现状,应从理顺产权关系,实现产权主体多元化;降低市场准入门槛;拓宽融资渠道等方面入手,完善民营经济发展的法律环境,进一步促进民营经济的发展。  相似文献   
84.
服装工艺课程教学改革探析   总被引:1,自引:0,他引:1  
<服装工艺>课程是高职服装设计专业的主干课,是一门实践性很强的课程.随着我国服装制造业的迅猛发展,社会和企业对服装人才的需求越来越强烈.要使学生具备一定的竞争能力,就要进行教学改革:根据专业特点和人才需求,修订教学大纲,突出课程的实践性和职业性:综合利用各种教学手段,改革考试方式,加强对学生动手能力的培养.  相似文献   
85.
可持续发展视角下江苏能源需求情景预测   总被引:3,自引:0,他引:3  
文章运用IPAT方程和指数分解的方法分析了江苏省2000—2007年的能源消耗及能源消费强度状况;根据江苏能源需求的历史发展趋势、小康社会指标以及发达国家能源利用状况分情景预测了江苏未来能源利用效率及能源需求总量。文章针对实现小康社会目标的各种情景,分析了经济结构对能源需求和能源强度的影响并提出政策建议。  相似文献   
86.
While it is often recognised that agricultural technology adoption decisions are intertwined and best characterised by multivariate models, typical approaches to examining adoption and impacts of agricultural technology have focused on single technology adoption choice and ignored interdependence among technologies. We examine farm‐ and market‐level impacts of multiple technology adoption choices using comprehensive household survey data collected in 2010/11 and 2012/13 in Ethiopia. Economic surplus analysis combined with panel data switching endogenous regression models are used to compute the supply shift parameter (K‐shift parameter), while at the same time controlling for the endogeneity inherent in agricultural technology adoption among farmers. We find that our improved technology set choices have significant impacts on farm‐level maize yield and maize production costs, where the greatest effect appears to be generated when various technologies are combined. The change in maize yield and production costs results in an average 26.4% cost reduction per kilogram of maize output (the K‐shift parameter). This increases the producer and consumer surpluses by US$ 140 and US$ 105 million per annum, respectively. These changes in economic surplus help to reduce the number of poor people by an estimated 788 thousand per year. We conclude that deliberate extension efforts and other policies that encourage integration of technologies are important for maize technologies to yield their full potential at both farm and market levels.  相似文献   
87.
The effect of different supplementary feeding rates for grazing cattle on high-altitude pastures dynamics was evaluated. A field experiment was carried out during three years in a subalpine pasture area of the Eastern Alps. The investigated pasture area was 40?ha, located between 1820 and 2230?m?a.s.l. Two paddocks were chosen in the experiment and two herds of 12 cattle each were kept in the two enclosures for 5 weeks. For the first herd (HS), the supplementary feeding rate was 4.8?kg?OM?head?1 per day, while for the second herd (LS), the rate was 1.6?kg?OM?head?1 per day. The amount of herbage consumed by each cattle was determined using the n-alkane technique. To monitor the pasture vegetation dynamics, eight metal exclusion cages were placed in each paddock to determine herbage growth, utilization rates, vegetation composition and animal grazing selectivity. Grazing behaviour of dairy cattle, in terms of herbage intake and species selection was affected by the different feeding rates. Cattle grazing Paddock HS consumed 1.9?kg?OM?day?1 of herbage less than Paddock LS. In the LS paddock, cattle grazed higher phytomass rates. When the animals were fed by higher concentrate rates, a more selective grazing seemed to significantly increase the pasture necromass component. The lower grazing selectivity favoured the development of species as Nardus stricta and Deschampsia caespitosa, which are well known for their low palatability. Distinct vegetation dynamic patterns were observed, with a reduction of hair grass and an increase of legumes in the Paddock LS.  相似文献   
88.
关于完全半解析函数的概念及性质的初步研究   总被引:1,自引:0,他引:1  
给出完全半解析函数及其可调和的概念。讨论了线性性质及封闭性,研究了完全半解析函数的可调和性。得到了完全半解析函数的一些可调和条件,给出了完全半解析函数的构成。  相似文献   
89.
This paper models for the first time a spatial process in local tax policies in the presence of centrally imposed fiscal limitations. Focusing on the frequently encountered case of a tax rate cap, we evaluate three empirical approaches to the analysis of spatially dependent limited tax policies: (i) a Bayesian spatial approach for censored dependent variables; (ii) a Tobit corner solution model augmented with a spatial lag; (iii) a spatial discrete hazard model. The evidence arising from an investigation of severely state‐constrained local vehicle taxes in Italy suggests that ignoring tax limitations can lead to substantial underestimation of inter‐jurisdictional fiscal interaction. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
90.
We investigate the relationship between ageing, cognitive abilities and retirement using the Survey on Health, Ageing and Retirement in Europe (SHARE), a household panel that offers the possibility of comparing several European countries using nationally representative samples of the population aged 50+. The human capital framework suggests that retirement may cause an increase in cognitive decline, since after retirement individuals lose the market incentive to invest in cognitive repair activities. Our empirical results, based on an instrumental variable strategy to deal with the potential endogeneity of retirement, confirm this key prediction. They also indicate that education plays a fundamental role in explaining heterogeneity in the level of cognitive abilities.  相似文献   
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