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171.
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John F. Due 《发展研究杂志》2013,49(2):263-276
In an increasing n umber of developing countries, as in virtually all of the major industrial countries, one or other form of sales taxation has taken root as an important provider of revenue, though in spite of much recent debate—much of it concerning the value added tax—no single form of sales taxation has emerged as being the most efficacious. This article does not discuss the merits of sales taxation, nor its effects or, development, but rather focuses on the question of which form of sales tax should be adopted assuming that one is to be. 相似文献
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John Charmley 《Diplomacy & Statecraft》2013,24(4):665-673
As Foreign Secretary, Castlereagh had to cope with the reality of France as an enemy as well as with France as a potential ally. This article examines the pragmatic evolution of Castlereagh's diplomacy from 1812, when an international coalition had to be brought and then kept together that could defeat Napoleon, to the aftermath of the Congress of Vienna, where France emerged as a vital part of the new European equilibrium. In settling Europe after nearly two decades of war the fate of France was central. 相似文献
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John K. Mullen Martin Williams Ronald L. Moomaw 《Journal of policy analysis and management》1996,15(1):51-67
This study focuses on the role of public capital stock in contributing to interstate differences in productive efficiency in manufacturing. Our motivation is to assess the role of public capital as a source of persistent regional variations in efficiency, and thus determine if public infrastructure policies might reasonably be expected to alter the competitive environment of a state's manufacturing sector. We use a stochastic frontier production function model, explicitly incorporating infrastructure capital, to examine the relative performance of the aggregate manufacturing sector across states and over time. We calculate an index of productive efficiency and estimate the determinants of statewide variations in it. These results show that variations in per capita infrastructure stocks significantly affect manufacturing efficiency. Considering the behavior of public capital as both a direct and an indirect input furthers our understanding of the role of infrastructure and its implications for regional economic development policies. 相似文献
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Accurate age estimates of immature necrophagous insects associated with a human or animal body can provide evidence of how long the body has been dead. These estimates are based on species-specific details of the insects’ aging processes, and therefore require accurate species identification and developmental stage estimation. Many professionals who produce or use identified organisms as forensic evidence have little training in taxonomy or metrology, and appreciate the availability of formalized principles and standards for biological identification. Taxonomic identifications are usually most readily and economically made using categorical and qualitative morphological characters, but it may be necessary to use less convenient and potentially more ambiguous characters that are continuous and quantitative if two candidate species are closely related, or if identifying developmental stages within a species. Characters should be selected by criteria such as taxonomic specificity and metrological repeatability and relative error. We propose such a hierarchical framework, critique various measurements of immature insects, and suggest some standard approaches to determine the reliability of organismal identifications and measurements in estimating postmortem intervals. Relevant criteria for good characters include high repeatability (including low scope for ambiguity or parallax effects), pronounced discreteness, and small relative error in measurements. These same principles apply to individuation of unique objects in general.
Key points
- Metrological rigour can increase in forensic entomology by selecting measurements based on their metrological qualities.
- Selection of high-quality features for morphological identification of organisms should consider these criteria: (1) pronounced discreteness of features (minimising group overlap or maximizing interval); (2) high repeatability of assessment (such as symmetrical width rather than asymmetrical length); (3) small relative error in measurement (selecting the physically largest continuous rigid feature for measurement).
- These metrological principles also apply to individuation of unique objects in general.
180.
大学是创新和社会进步的源泉 总被引:1,自引:0,他引:1
约翰·亨尼斯 《国家教育行政学院学报》2006,(9):13-16,81
大学是创新和社会进步的源泉。大学不仅可以支持并推动知识进步,更重要的贡献在于新发明和创新。由于大学长期关注基础性研究,因而比其他机构更容易开展创新活动。大学通过创新提高人们的生活水平、推动经济发展,进而推动社会的进步。易于创新的研究环境必须具有必要的内外部条件。内部条件主要有三个:一是要选对人;二是要时刻处于技术的前沿;三是要寻找那种跨越性的技术。外部条件主要有两个:一是大学与业界应互相尊重、相辅相成,形成双赢局面;二是创新的转化需要为技术突破提供肥沃的土壤和精心的照料。 相似文献