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41.
以学界广为关注的“S(是)AV(())的”句式为例,重点分析“(是)……的”类句式在语境、词汇和句法三个层面所显示的不同已然义特征,并以此为基础对国内外关于已然义“(是)……的”类句式的相关研究进行简要的评价。 相似文献
42.
Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states. 相似文献
43.
Power comparison of the Kolmogorov–Smirnov test under ranked set sampling and simple random sampling
Yusuf Can Sevil 《Journal of Statistical Computation and Simulation》2017,87(11):2175-2185
Many studies have been used to compare the power of several goodness-of-fit (GOF) tests under simple random sampling (SRS) and ranked set sampling (RSS). In our study, a different design procedure and ranking process in RSS are thoroughly investigated. A simulation study is conducted to compare the power of the Kolmogorov–Smirnov test under SRS and RSS with different sets and cycle sizes for several distributions. Level-2 sampling design and partially rank-ordered sets are used. Also, we benefited from auxiliary variables in the ranking process. Finally, results are presented with tables and figures. Under these conditions we show that the RSS has better performance against the SRS in finite population. 相似文献
44.
在美国的多元政治体制下,其联邦官僚系统保持着一定程度的自主性。与之同时,又接受着来自国会、总统和社会利益集团等多种政治主体的影响和控制,形成"一仆二主"乃至"一仆多主"的现象。基于美国的民主原则,美国联邦官僚系统必须回应来自政治系统的意愿和利益要求,接受其监督,同时凭借自身的专业技术能力及其他职业性资源,又保持着相对独立性,呈现出美国政治中特有的政治行政关系结构和特征。 相似文献
45.
William C. Fleming 《Mobilities》2014,9(1):42-62
Regulatory shifts in US border policy set in motion through implementation of the Western Hemisphere Travel Initiative are concurrent with recent formal and functional changes to the US passport. This article examines these modifications interweaving themes of boundary, mobility, and identity. The study focuses on the tripartite means by which the state employs the passport: as the primary affixer of national identity; as a mediator of contact and mobility across national boundaries; and as a mode for the projection of a certain territorial discourse to its citizenry and ‘others.’ These concepts are developed through an analysis of the narrative and iconic representations contained within the new book itself; material sources from government archives; as well as discussions and interviews with US State Department functionaries closely associated with the design and distribution of the new e-passport. Through the latter examination, a view is afforded into the process by which key state documents are crafted and an inherent tension revealed within an agency charged with establishing a particular unifying ‘brand’ for the preeminent instrument of national identification, whilst dutifully acknowledging the diverse constituency of a nation that historically fashions itself as one constructed from the many. In conclusion, the study suggests that the new passport is the handiwork of a plethora of state actors and a servant of many masters, for it is not only a facilitator of mobility and a vouchsafe for the identity of the bearer, but also, a tiny but significant piece of US property, itself an agent of border maintenance and boundary construction that enables the state to lay claim to its citizenry. 相似文献
46.
理查德·泰勒 《北京邮电大学学报(社会科学版)》2009,11(2):14-22
本文概述了当前美国有线电视行业/付费视频行业的局势,以及一些重要问题和面临的挑战,展望了未来的视频市场,概述了一个未来视频/宽带市场的战略愿景,然后回归到政策建议及具体的立法和管制行动。这将帮助我们在最短的、可操作的时间内通向一个开放的、非歧视性的、无处不在的宽带网络。 相似文献
47.
Xiaofeng Steven Liu 《统计学通讯:模拟与计算》2013,42(6):1433-1436
This short article shows an unified approach to representing and computing the cumulative distribution function for noncentral t, F, and χ2. Unlike the existing algorithms, which involve different expansion and/or recurrence, the new approach consistently represents all the three noncentral cumulative distribution functions as the integral of the normal cumulative distribution function and χ2 density function. 相似文献
48.
Let T2 i=z′iS?1zi, i==,…k be correlated Hotelling's T2 statistics under normality. where z=(z′i,…,z′k)′ and nS are independently distributed as Nkp((O,ρ?∑) and Wishart distribution Wp(∑, n), respectively. The purpose of this paper is to study the distribution function F(x1,…,xk) of (T2 i,…,T2 k) when n is large. First we derive an asymptotic expansion of the characteristic function of (T2 i,…,T2 k) up to the order n?2. Next we give asymptotic expansions for (T2 i,…,T2 k) in two cases (i)ρ=Ik and (ii) k=2 by inverting the expanded characteristic function up to the orders n?2 and n?1, respectively. Our results can be applied to the distribution function of max (T2 i,…,T2 k) as a special case. 相似文献
49.
刘淑霞 《西南石油大学学报(社会科学版)》2009,33(2):133-136
针对大庆外围油田特低渗透油藏剩余油潜力大、井网加密效益差、水驱采收率低等问题,提出了特低渗透油藏 CO2驱技术。通过细管实验和天然岩芯 CO2 驱油实验,确定了 CO2 与高台子油田原油的最小混相压力,评价了特低渗透砂岩油藏 CO2 驱油效果。实验结果表明,CO2 驱可以应用于高台子油田,并取得较好的驱油效果。当天然岩芯空气渗透率为0.58 mD 时,在水驱基础上,气驱可以进一步提高采收率 8% 以上,特低渗透油藏实施 CO2 驱油技术是可行的。 相似文献
50.
本文引入了同时考虑用能权与碳排放权初始分配的零和DEA方法,从公平与效率视角对比分析了历史法与零和DEA方法两种分配方式的适用性,并应用市场交易模型检验了不同初始分配方式对各地区交易行为的影响。研究结果表明,零和DEA方法能够提高用能权与碳排放权初始分配的公平性,但却是以牺牲前沿技术效率水平为代价。其次,完善的市场机制能够提高基于零和DEA方法调配用能权与碳排放权的配置效率,生产技术水平较高的地区可以通过出售多余的用能权和碳排放权来获得额外收益,有利于促进绿色技术创新;相反,历史法容易导致高耗能、高排放的地区在初始分配中获得较多的用能权和碳排放权,不利于正向促进技术进步。最后,当市场机制不完善时,基于零和DEA方法配置用能权和碳排放权,可能会抑制技术进步,而基于历史法的初始分配方式则至少可以在短期内维持现有生产技术水平。 相似文献