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61.
China's energy inefficiency: A cross-country comparison   总被引:2,自引:0,他引:2  
This paper constructs a total-factor energy technical efficiency index using the data envelopment analysis (DEA) method following the total factor productivity framework. We then compare energy technical efficiency across 156 countries from 1980 to 2007. The results show that China's energy efficiency considerably trails other countries’ although it has made significant gains within the last 28 years. Further analysis indicates that scale inefficiency rather than pure technical efficiency contributes to China's energy inefficiency.  相似文献   
62.
The class $G^{\rho,\lambda }$ of weighted log‐rank tests proposed by Fleming & Harrington [Fleming & Harrington (1991) Counting Processes and Survival Analysis, Wiley, New York] has been widely used in survival analysis and is nowadays, unquestionably, the established method to compare, nonparametrically, k different survival functions based on right‐censored survival data. This paper extends the $G^{\rho,\lambda }$ class to interval‐censored data. First we introduce a new general class of rank based tests, then we show the analogy to the above proposal of Fleming & Harrington. The asymptotic behaviour of the proposed tests is derived using an observed Fisher information approach and a permutation approach. Aiming to make this family of tests interpretable and useful for practitioners, we explain how to interpret different choices of weights and we apply it to data from a cohort of intravenous drug users at risk for HIV infection. The Canadian Journal of Statistics 40: 501–516; 2012 © 2012 Statistical Society of Canada  相似文献   
63.
Typically, qualitative comparative analysis (QCA) is praised for its hermeneutic dialogue between theory and empirical cases. However, in reporting research with QCA, these hermeneutic processes will usually not be illustrated. This paper aims at showing clear how QCA induces this dialogue between theory and data. As an illustrative example, I use a research situation dealing with a genuine research question of Legislative Studies: the causes of party unity. Using the classical dichotomous and the MV-QCA approach, the paper mainly shows how to deal productively with contradictory theoretical statements and how stepping from simpler to more complex models adds explanation while still making clear further routes to improve insights into the substantive research topic: both theoretically and empirically. Finally, non-observed configuration (‘logical remainders’) will be used to simplify the resulting theory, and its theoretical and empirical plausibility will be evaluated. The whole paper makes explicit how the QCA approach forces researchers to reveal the dialogue between theory and cases – just as it was intended by the inventor of this analytical tool.  相似文献   
64.
Although theoretical foodweb models predict the presence of only three to four trophic categories, estimation of “potential” vertical foodweb structure from species lists and inferred feeding interactions suggest that as many as 7 trophic categories can occur in the pelagic foodwebs of North American glaciated lakes. A compilation of data on the nitrogen isotopic composition of zooplankton from 46 Canadian Shield lakes suggested the average existence of one “realized” trophic category in addition to that of filter-feeding, herbivorous cladocerans. When phytoplankton, planktivorous invertebrates, and plantivorous and piscivorous fish are included, the vertical foodweb structure in the pelagic zones of these lakes are greater than those hypothesized from some theoretical models.  相似文献   
65.
We use book translations as a new measure of international idea flows and study the effects of Communism's collapse in Eastern Europe on these flows. Using novel data on 800,000 translations and difference‐in‐differences approaches, we show that while translations between Communist languages decreased by two thirds with the collapse, Western‐to‐Communist translations increased by a factor of 4 and quickly converged to Western levels. Convergence was more pronounced in the fields of applied and social sciences, and was more complete in Satellite and Baltic than in Soviet countries. We discuss how these patterns help us understand how repressive institutions and preferences towards Western European ideas shaped the international diffusion of knowledge.  相似文献   
66.
基于建构主义对语言和社会现实的观点,本文应用认知语言学中概念隐喻的理论,采用定性的方法,分析了《中国日报》上甲流报道中的隐喻系统。研究发现该报把甲流隐喻化为一个贪婪和狡诈的凶手,威胁着整个人类的健康;在这个基本的隐喻体系下,存在多个分隐喻,这些隐喻构成层级关系的网络。在此基础之上,本文进而讨论了使用概念隐喻的动因;认为通过隐喻网络,该报纸向读者传递了一个隐性的陈述,同时表明该报的立场和态度。本研究不但拓展了van Dijk的价值对立方块理论,为话语分析开辟了新的路径;而且以媒体话语为分析对象,说明了概念隐喻与意识形态之间的互构关系。  相似文献   
67.
本文从句法和语用角度分析了"V—N"与"用N V"格式,探讨了它们的差异和区别。现代汉语中类似于"踢—脚"、"切—刀"的"V—N"格式可以转化为"用脚踢(—下)"、"用刀切(—下)"的"用N V"的格式。但是这种转换是单项的,两者存在许多相异之处:格式对句法成分、相关句式都有特定要求;语用上存在着工具义隐现与否、语体风格的差异以及有无焦点的区别。  相似文献   
68.
特拉伊宁的犯罪构成理论及其对苏俄刑法的影响   总被引:1,自引:0,他引:1  
特拉伊宁的刑法思想经历了从刑事古典学派和刑事社会学派向以马克思主义哲学为指导的社会主义刑法理论的转变过程。他以唯物主义哲学为根据,从批判资本主义犯罪构成的"客观结构"和"主观结构"的缺陷入手,提出了主客观相统一的四要件犯罪构成理论。在该理论中,犯罪构成被看作是犯罪事实的核心组成部分。由于该理论在苏俄刑法中的具体运用,犯罪构成成为苏俄刑法刑事责任认定的唯一根据,并最终促成主客观相统一原则在苏俄刑法中的确立。  相似文献   
69.
The 2-INTERVAL PATTERN problem is to find the largest constrained pattern in a set of 2-intervals. The constrained pattern is a subset of the given 2-intervals such that any pair of them are R-comparable, where model . The problem stems from the study of general representation of RNA secondary structures. In this paper, we give three improved algorithms for different models. Firstly, an O(n{log} n +L) algorithm is proposed for the case , where is the total length of all 2-intervals (density d is the maximum number of 2-intervals over any point). This improves previous O(n 2log n) algorithm. Secondly, we use dynamic programming techniques to obtain an O(nlog n + dn) algorithm for the case R = { <, ⊏ }, which improves previous O(n 2) result. Finally, we present another algorithm for the case with disjoint support(interval ground set), which improves previous O(n 2n) upper bound. A preliminary version of this article appears in Proceedings of the 16th Annual International Symposium on Algorithms and Computation, Springer LNCS, Vol. 3827, pp. 412–421, Hainan, China, December 19–21, 2005.  相似文献   
70.
讨论了两种迭代的异同,得到了以下结果:①同高连续数对在两种迭代下的不变性;②数对 n和n+2k的轨迹序列和奇偶矢量之间的关系。  相似文献   
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