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801.
农产品供应链物流指的是农产品在营销过程中,在供应链上所有物流的统称。农产品供应链物流的金融模式一方面指具有发展能力的物流企业为农产品营销提供金融支持,另一方面是指银行为农产品供应链物流提供金融支持。因此,农产品在营销过程中,供应链物流、金融均起到不可替代的作用。文中分析了农产品供应链物流的落后现状,提出金融支持是解决农产品供应链物流困境的唯一出路。  相似文献   
802.
文章以供应链环境下企业间的产品创新为研究对象,分析了供应链环境下产品合作创新的影响因素,将供应链合作创新模式概括为技术转让、合作开发、创新网络、技术联盟、共建实体等5种。通过合作模式演进图描述了企业在技术、资金、人员和组织形式4方面深入合作、不断演进的过程。最后,提出了供应链产品创新的匹配模型。  相似文献   
803.
    
This paper examines the impact of uncertainty on estimated response of stock returns to U.S. monetary policy surprise. This is motivated by the Lucas island model which suggests an inverse relationship between the effectiveness of a policy and the level of uncertainty in the economy. Using high frequency daily data from the Federal funds futures market, we first estimate the response of S&P 500 stock returns to monetary policy surprises within the time varying parameter (TVP) model. We then analyze the relationship of these time varying estimates with the benchmark VIX index and alternative measures of uncertainty. Evidence suggests a significant negative relationship between the level of uncertainty and the time varying response of S&P 500 stock returns to unanticipated changes in the interest rate. Thus, at higher levels of uncertainty the impact of monetary policy shocks on stock markets is lower. The results are robust to different measures of uncertainty.  相似文献   
804.
文章简述了Suroca排水渠工程在技术管理、资源管理、质量管理以及安全文明施工的一些经验,通过对排水渠工程施工管理,为安哥拉市政工程的施工提供借鉴。  相似文献   
805.
李莹 《价值工程》2012,31(1):248
国家示范性高职院校建设的核心是建设高水平的专业,通过若干高水平的重点专业建设,形成若干个强势专业群,从而起到示范带动作用。共同打造精品专业是校企合作的切入点,是培养双师型队伍建设的有效途径,能够增强校企实训基地产学研结合工作的开展。  相似文献   
806.
    
It is very common in applied frequentist (\"classical\") statistics to carry out a preliminary statistical (i.e. data-based) model selection by, for example, using preliminary hypothesis tests or minimizing AIC. This is usually followed by the inference of interest, using the same data, based on the assumption that the selected model had been given to us  a priori . This assumption is false and it can lead to an inaccurate and misleading inference. We consider the important case that the inference of interest is a confidence region. We review the literature that shows that the resulting confidence regions typically have very poor coverage properties. We also briefly review the closely related literature that describes the coverage properties of prediction intervals after preliminary statistical model selection. A possible motivation for preliminary statistical model selection is a wish to utilize uncertain prior information in the inference of interest. We review the literature in which the aim is to utilize uncertain prior information directly in the construction of confidence regions, without requiring the intermediate step of a preliminary statistical model selection. We also point out this aim as a future direction for research.  相似文献   
807.
文章介绍了红水河岩滩水电站水文预报的方案、内容及作业方法。  相似文献   
808.
A variety of methods and ideas have been tried for electricity price forecasting (EPF) over the last 15 years, with varying degrees of success. This review article aims to explain the complexity of available solutions, their strengths and weaknesses, and the opportunities and threats that the forecasting tools offer or that may be encountered. The paper also looks ahead and speculates on the directions EPF will or should take in the next decade or so. In particular, it postulates the need for objective comparative EPF studies involving (i) the same datasets, (ii) the same robust error evaluation procedures, and (iii) statistical testing of the significance of one model’s outperformance of another.  相似文献   
809.
Extant literature on sustainable business models highlights that value creation stems from resources exchanged in relationships between a focal firm and its stakeholders. In this context, the literature has, so far, focused on direct relationships. However, despite the acknowledged relevance of sustainability issues in supply chains, this relational view of the focal company and its direct stakeholders has not been extended toward value creation for and with indirect stakeholders, such as stakeholders of suppliers. Addressing this gap, this conceptual article integrates a relational view of sustainable supply chain management into the management of sustainable business models. It extends the scope of sustainable business models from relationships between the focal firm and its direct stakeholders to indirect relationships with stakeholders of suppliers. A framework is developed that supports analysis and management of value-creating relationships between the focal firm, suppliers, and stakeholders of suppliers. By extending the conceptualization of sustainable business models to consider relationship chains beyond direct relationships, this article proposes that a focal firm has to actively manage interactions both with suppliers and with suppliers' stakeholders.  相似文献   
810.
    
In the analysis of clustered and longitudinal data, which includes a covariate that varies both between and within clusters, a Hausman pretest is commonly used to decide whether subsequent inference is made using the linear random intercept model or the fixed effects model. We assess the effect of this pretest on the coverage probability and expected length of a confidence interval for the slope, conditional on the observed values of the covariate. This assessment has the advantages that it (i) relates to the values of this covariate at hand, (ii) is valid irrespective of how this covariate is generated, (iii) uses exact finite sample results, and (iv) results in an assessment that is determined by the values of this covariate and only two unknown parameters. For two real data sets, our conditional analysis shows that the confidence interval constructed after a Hausman pretest should not be used.  相似文献   
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