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101.
Christa D. Jensen Donald J. Lacombe Stuart G. McIntyre 《Papers in Regional Science》2013,92(3):651-666
The Conservative Party won the 2010 General Election in the United Kingdom, gaining the most votes and seats of any single party. Using Bayesian spatial econometric methods, we show that significant spatial dependence exists in Conservative voting behaviour and select the spatial Durbin model as the best model to explain this phenomenon. This paper examines these spatial effects as well as the effects of a range of economic, socio‐economic, and political variables. Perhaps the most interesting result is that incumbency has effects beyond an incumbent's own constituency. 相似文献
102.
Salman M. A. Salman 《国际水》2013,38(2):283-288
Abstract Water is a finite resource, and with the considerable upsurge in population, urbanization, and industrialization, it is also becoming an increasingly scarce resource. Many countries in the world rely on river waters, and many of those rivers are shared by two or more countries. Dams on those rivers have been a major source of tensions, disputes, and, in some cases, even conflict between riparian countries because dams could result in massive diversion of river flows. Those developments have, inter alia, highlighted the relevance and importance of the principles of international water law, as reflected in the United Nations Convention on the Law of the Non-Navigational Uses of International Watercourses. The World Commission on Dams has also underscored the importance of, and elaborated on, those principles with regard to dams on shared rivers. This article discusses and analyzes the recommendations of the Commission in this area, and compares them with the principles of international water law as enunciated in the United Nations Convention 相似文献
103.
In this paper, -principal cycles of surfaces immersed in 4 are studied. In terms of geometric invariants, an integral expression for the first derivative of the Poincaré mapping associated with a -principal cycle is obtained. 相似文献
104.
To date, long-term preservation approaches have comprised of emulation, migration, normalization, and metadata – or some combination
of these. Most existing work has focussed on applying these approaches to digital objects of a singular media type:
text, HTML, images, video or audio. In this paper, we consider the preservation of composite, mixed-media digital objects,
a rapidly growing class of resources. We describe an integrated, flexible system that we have developed, which leverages existing
tools and services and assists organizations to dynamically discover the optimum preservation strategy as it is required.
The system captures and periodically compares preservation metadata with software and format registries to determine those
objects (or sub-objects) at risk. By making preservation software modules available as Web services and describing them semantically
using a machine-processable ontology (OWL-S), the most appropriate preservation service(s) for each object (or sub-object)
can then be dynamically discovered, composed and invoked by software agents (with optional human input at critical decision-making
steps). The PANIC system successfully illustrates how the growing array of available preservation tools and services can be
integrated to provide a sustainable, collaborative solution to the long-term preservation of large-scale collections of complex
digital objects. 相似文献
105.
近年来,SOC设计方法学的研究越来越引起人们的注意。C语言适合对系统进行高层次的描述。C语言的系统描述经过软硬件划分之后,要求将硬件实现部分转换为适合于综合的VHDL语言。文章通过分析两种语言的区别,提出并实现了适于表达C语言描述内容的VHDL结构形式,并对几种C语言结构提出合理的转换方案。实验表明,文章提出的方案是正确的和有效的。 相似文献
106.
We show that local quantities of interest such as displacements or stresses of a FE–solution can be calculated with improved accuracy if fundamental solutions are employed. The approach is based on Bettis theorem and an integral representation of the local quantities via Greens function. The unknown Greens function is split into a regular part and a fundamental solution so that only the regular part must be approximated on the finite element ansatz space. Some numerical studies for linear elasticity will illustrate our approach. 相似文献
107.
西南国际诸河包括澜沧江、怒江、红河和伊落瓦底江,4大流域在我国境内总流域面积约41万km^2,本文论述诸流域水能资源量分布特点及其开发利用条件,开发程度,根据化、西南地区各(区)21世纪中叶经济发展,电力规划和区域电网结构设计的可能性,开发西部水能资源,实现了“西电东送”的目标,提出分阶段水电开发设想,重点是21世纪前20年。西南国际诸河水能资源丰富,根据初步复核的技术可开发装机容量为5298.17万KW,年发电量2577.44亿KW.h。装机容量按河流分澜沧江57.71%,怒江占30.38%、红河和伊洛瓦底河两江仅占11.91%,至1995年开发程度仅为4.93%,说明西南国际诸河尚有大量的水能资源待开发。为加快我国西南部地区经济的发展,促进东西部经济共同繁荣,必须加大西南国际诸河的水能资源开发利用,这也符合目前国家的西部开发策略。 相似文献
108.
CHEN Qiang CHEN He-xin SANG Ai-jun Key Laboratory of New Communication Technology School of Communication Engineering Jilin University Changchun China 《中国邮电高校学报(英文版)》2007,14(2):112-119
In this article, a new way to evaluate the quality of color images is proposed, in which the properties of human vision psychology, objective fidelity, edge information, and color distortion will be combined through utilizing 3-D matrix transform. There exists color redundancy and structural similarity between three different frames of a color image, the definition of vision properties will be measured by 3-D submatrix integration transform (SIT), in which three color components are integrated into one model and color redundancy can be exploited fully. The simulation results show that the measure index is very effective and objective in accord with vision properties. 相似文献
109.
《30 MHz~3000 MHz地面数字音频广播系统技术规范》即通常所说的DAB(数字音频广播)中国标准虽然是针对于音频的,但是考虑到基带部分是信源透明的,所以完全可以作为手机电视的传输网络。文中在兼容DAB标准的情况下提出了一种单频网切换的方案,以实现服务的平滑过渡。通过对ETSI协议的相关补充并采用二级检索的机制保证了接收机在地域切换时信号的连续性,最后通过软件仿真的方法从视觉直观上验证了该方法的效果,从而确定了该方案的可行性。 相似文献
110.
在流量测量中,超声波测流量以其非接触测量方式、智能化以及测量范围广等优点被广泛应用。针对超声波流量测量的优点,该设计开发了一套八路巡检的超声波时差法流量测量装置,该测量装置采用了主控制器STM32和高精度计时芯片TDC-GP21,通过对信号的升压发射处理和八路测量通道的切换,用以测量小管径、低流速、单向流体的管道内流量。该测量装置采用高压驱动超声波换能器,提高了装置的抗干扰能力,大大减少了使用成本,并且通过软件的方法有效地抑制了流量装置的零点漂移,提高了测量装置的计量精度。 相似文献