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1.
以重庆市甄子岩29号危岩体为研究对象,基于现场调查和分析解剖,建立UDEC离散元数值计算模型,对其演化变形过程进行模拟分析。研究表明,在巨大的自重作用下,由于基座岩体岩质软,岩体较破碎,且基座外侧为直立的陡崖,具有完整的临空面,从而使基座岩体易发生压缩流变及剪切流变,进而使危岩体存在滑移垮塌的危险。 相似文献
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探究黑龙江旅游网络关注度时空演变特征对黑龙江旅游业良性发展具有重要意义.利用百度指数获取2011—2018年全国和分地区黑龙江旅游网络关注度逐日搜索指数数据.从时间分布、空间分布、时空集聚3个方面研究其演变特征.研究表明:2011—2018年全国黑龙江旅游网络关注度年际变化总体呈现上升趋势,月际变化呈"W"形;2011—2018年31个省区市黑龙江旅游网络关注度空间差异较大、季节性影响显著;东部地区黑龙江旅游网络关注度偏高,西部地区黑龙江旅游网络关注度的季节差异最明显;东部地区内的黑龙江旅游网络关注度差异性最小,西部地区内差异性最大;黑龙江旅游网络关注度具有正空间自相关,部分东部、中部地区表现为高高集聚,多数西部地区表现为低低集聚. 相似文献
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文中详细地阐述了取河水、井水、水库水、跨流城引(排)水等不同情况进行还原的具体方法步骤。并对水量还原成果提出合理性检查措施。 相似文献
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This article reviews the law regarding Title VII employment discrimination protection from religious discrimination. The issues surrounding the principal legal protection in this regard are explored in the context of a recent controversial case in which an author, Forrest Mims, was not hired as a regular contributor forScientific American magazine, ostensibly because of his belief in the theory of creation over the theory of evolution. The definition of what constitutes a protected religious belief or practice is seen to have expanded over time. However, a belief in creationism is not necessarily seen as being tantamount to a religious belief under present legal interpretation of Title VII. The implications of this finding for future needed Title VII revision are discussed. 相似文献
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Karl Wrneryd 《Games and Economic Behavior》2002,41(2):77
We study the evolution of an economy where agents who are heterogeneous with respect to risk attitudes can either earn a certain income or enter a risky rent-seeking contest. We assume that agents behave rationally given their preferences, but that the population distribution of preferences evolves over time in response to material payoffs. We show that, in particular, initial distributions with full support converge to stationary states where all types are still present. Although rents are perfectly dissipated in material terms at a steady state, efficiency is greater than if everybody had been risk neutral, since risk lovers specialize in rent seeking. 相似文献
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The present paper demonstrates the applicability of population based search optimization method, namely, Differential Evolution
(DE) to a case study of Mahi Bajaj Sagar Project (MBSP), India. Ten different strategies of DE are employed to assess the
ability of DE for solving higher dimensional problems as an alternative methodology for irrigation planning. The parameters
considered in DE are population size, crossover constant and weighting factor. Linear Programming (LP) is utilized as a comparative
approach to assess the ability of DE. Comparison of results of LP and the 10 DE strategies for the given parameters indicated
that both the results are comparable even for high dimensional problems. Extensive sensitivity analysis studies, performed
for 3,600 combinations of above parameters for the 10 DE strategies suggested that DE/rand-to-best/1/bin strategy is the best
strategy giving maximum benefits taking minimum CPU time. It is concluded that DE can be utilized for efficient planning of
any irrigation system with suitable modifications. 相似文献
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Brigitte Eierle 《Accounting, Business & Financial History》2005,15(3):279-315
Based on a contingent perspective of accounting change, this paper reviews the historical development of differential reporting in Germany, by drawing on primary and secondary sources. The main objective of the paper is to shed light on the driving forces and main influential parameters that have shaped the existing differential reporting framework. This historical approach supplies interesting insights for the current discussion on differential reporting in Germany produced by the EU Regulation on the application of International Accounting Standards. 相似文献
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