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381.
自贸区对所属城市创新能力具有直接推动作用。选取福建省为评价对象,应用改进熵值法,实证分析自贸区所属城市创新驱动发展要素及互动关系,指出科技进步、政策支撑、产业参与和环境匹配是区域创新的重要因素,在资源秉赋差异明显的情况下,应着力推进科研投入与措施创新,并加快人才培育和产业集聚。 相似文献
382.
农业品牌化是农业工业化和现代化的重要标志,也是提高农产品质量安全水平和市场竞争力的重要途径。我国正处在农业品牌化的初级阶段,对农产品品牌竞争力评价的探讨是农业品牌化理论研究的重要组成部分,也将在实践上对农产品品牌竞争力的提高起到积极的引导和促进作用。文章经过理论分析构建了以市场评价和质量评价为主,兼顾效益评价和潜力评价的农产品品牌评价指标体系,并采用了层次分析法确定指标权重,用综合评分法确定分值,得出对农产品品牌竞争力的相对评价。 相似文献
383.
《Omega》2014
Electricity consumption forecasting has been always playing a vital role in power system management and planning. Inaccurate prediction may cause wastes of scarce energy resource or electricity shortages. However, forecasting electricity consumption has proven to be a challenging task due to various unstable factors. Especially, China is undergoing a period of economic transition, which highlights this difficulty. This paper proposes a time-varying-weight combining method, i.e. High-order Markov chain based Time-varying Weighted Average (HM-TWA) method to predict the monthly electricity consumption in China. HM-TWA first calculates the in-sample time-varying combining weights by quadratic programming for the individual forecasts. Then it predicts the out-of-sample time-varying adaptive weights through extrapolating these in-sample weights using a high-order Markov chain model. Finally, the combined forecasts can be obtained. In addition, to ensure that the sample data have the same properties as the required forecasts, a reasonable multi-step-ahead forecasting scheme is designed for HM-TWA. The out-of-sample forecasting performance evaluation shows that HM-TWA outperforms the component models and traditional combining methods, and its effectiveness is further verified by comparing it with some other existing models. 相似文献
384.
李雪 《绍兴文理学院学报》2009,29(8)
利用柠檬酸-凝胶方法,以Y2O3,Eu2O3,Tb4O7和Al(NO3)3·9H2O作为初始原料,柠檬酸作为配位剂,成功制备出了Y3Al5O12:Eu3+(Tb3+)发光材料,其烧结温度为1?000℃,时间4?h.通过X射线衍射测试,表征Y3Al5O12为单相;计算其晶胞参数,发现晶胞体积v随着pH值的增大而增大.对Y3Al5O12:Eu3+(Tb3+)系列样品在紫外光谱区域和真空紫外光谱区域的发光性能进行了研究,结果表明:在真空紫外光谱区域激发下,Eu3+(Tb3+)的猝灭浓度比在紫外光谱区域激发下的低. 相似文献
385.
Bivariate rank set sample (BVRSS) matched pair sign test is introduced and investigated for different ranking based schemes. We show that this test is asymptotically more efficient and more powerful than its counterpart sign test based on a bivariate simple random sample (BVSRS) for different ranking schemes. The asymptotic null distribution and the efficiency of the test are derived. Pitman’s asymptotic relative efficiency is used to compare the asymptotic performance of the matched pair sign test using BVRSS versus using BVSRS in all ranking cases. For small sample sizes, the bootstrap method is used to estimate P-values. Numerical comparisons are used to gain insight about the efficiency of the BVRSS sign test compared to the BVSRS sign test. Our numerical and theoretical results indicate that using any ranking scheme of BVRSS for the matched pair sign test is more efficient than using BVSRS. 相似文献
386.
杨英法 《河北建筑科技学院学报(社会科学版)》2009,(4):72-75
传统的教材编纂法属于"显示完美式教材编纂法",力求显示教材已将相应领域的问题都圆满解决,对于其中存在的问题不有意加以显示,甚至有意加以掩藏,故无法激发学生的创新意识、创新能力,甚或对创新有抑制作用。应采用"显示问题式教材编纂法",力求将相应领域存在的各种问题显示出来,使学生产生创新的意念,明了创新的着力点,从而有力地促进学生创新能力的提高。 相似文献
387.
通过乌坑坝隧道北京端左线冲沟地段的施工实例,介绍渗水软弱围岩浅埋偏压隧道地表双液注浆锚管加固的施工方法,并对加固效果及其优缺点进行分析. 相似文献
388.
Wonsun Chen 《统计学通讯:理论与方法》2013,42(6):1153-1171
We consider a recently introduced nonparametric model for Analysis of Covariance and derive an asymptotic test for interaction between covariate and treatment. Furthermore, we suggest data depth techniques to obtain joint confidence regions for the covariate effects in this model. The finite sample behavior of the asymptotic method is evaluated in simulations. Application of the procedures is illustrated using an epileptic seizures and chemotherapy data set. 相似文献
389.
Gabriele Brondino 《统计学通讯:模拟与计算》2013,42(2):407-417
The standard tensile test is one of the most frequent tools performed for the evaluation of mechanical properties of metals. An empirical model proposed by Ramberg and Osgood fits the tensile test data using a nonlinear model for the strain in terms of the stress. It is an Error-In-Variables (EIV) model because of the uncertainty affecting both strain and stress measurement instruments. The SIMEX, a simulation-based method for the estimation of model parameters, is powerful in order to reduce bias due to the measurement error in EIV models. The plan of this article is the following. In Sec. 2, we introduce the Ramberg–Osgood model and another reparametrization according to different assumptions on the independent variable. In Sec. 3, there is a summary of SIMEX method for the case at hand. Section 4 is a comparison between SIMEX and others estimating methods in order to highlight the peculiarities of the different approaches. In the last section, there are some concluding remarks. 相似文献
390.
In earlier work (Gelfand and Smith, 1990 and Gelfand et al, 1990) a sampling based approach using the Gibbs sampler was offered as a means for developing marginal posterior densities for a wide range of Bayesian problems several of which were previously inaccessible. Our purpose here is two-fold. First we flesh out the implementation of this approach for calculation of arbitrary expectations of interest. Secondly we offer comparison with perhaps the most prominent approach for calculating posterior expectations, analytic approximation involving application of the LaPlace method. Several illustrative examples are discussed as well. Clear advantages for the sampling based approach emerge. 相似文献