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181.
物权法是近代社会不可缺少的法律制度,没有这一法律制度,就没有真正意义的民法,或者是真正意义上的市场经济制度;我国物权法的出台对坚持改革开放和社会主义市场经济建设的正确方向,正确评价市场经济建设的成果,有着十分重要的意义;物权法以规范人对财产的支配关系为内容,性质上属于财产法。因此,所有权的法律制度是物权法的核心内容,财产不受侵犯是物权法的核心理念。只要是合法获得的财产,法律必须给予平等保护。这不仅是物权法应有的立法态度,也是市场经济和现代社会应有的基本原则。无论谁所有,从合法财产受保护层面上讲都是神圣的,都是不受侵犯的。  相似文献   
182.
Time of peak bat activity during the night differs among bat species due to temperature, prey availability, habitat availability, and/or interactions between species. Habitat availability is altered in urban areas, which may affect insect prey availability and interspecies interactions. Our objectives were to use mobile acoustic monitoring to determine when bat species were active in a single night in urban and nonurban sites and if nightly bat activity patterns differed in urban versus nonurban sites. Bat echolocation call sequences were recorded using Anabat acoustic detectors while driving transects through the night at five sites (three “urban” and two “nonurban”) located in the Piedmont region of north-central North Carolina from May through August 2016. Transects were driven three times per night starting 45 min, 180 min, and 300 min after sunset. Recorded echolocation call sequences were analyzed manually using AnalookW and automatically using Bat Call Identification and Echoclass software. Total bat activity was not different between urban and nonurban sites. However, total bat activity was lower later in the night in urban sites, but stayed the same in nonurban sites. Species specifically, there were more Eptesicus fuscus, Lasionycteris noctivagans, and Tadarida brasiliensis call sequences and fewer Lasiurus borealis, Nycticeius humeralis, and Perimyotis subflavus call sequences in urban sites than nonurban sites. There were also fewer E. fuscus, L. noctivagans, and N. humeralis call sequences later in the night in both urban and nonurban sites. Only Lasiurus borealis activity in urban sites later in the night reduced and L. borealis activity in nonurban sites remained at the same. These results suggest that bats in urban areas partition time differently, which is important to consider for urban conservation efforts and planning.  相似文献   
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184.
文章对一类与洛伦茨曲线相关的不平等测度指数进行了较为系统的回顾与探讨,这些指数既包括基尼系数和Schutz指数等传统的不平等测度指数,也包括Bonferroni指数、De Vergottni指数和Zenga指数等国际上应用广泛但国内少见的不平等指数,并揭示了这些指数间的相互关联,总结了这些指数所满足的性质特征.  相似文献   
185.
文章通过构建月度景气指标与季度实际GDP增长率之间的混频动态向量自回归模型,并采用期望最大值算法和卡尔曼滤波来实现混频数据和缺失数据的估计和迭代预测.大量月度景气指标的MFVAR模型的伪实时数据的多步滚动迭代样本外预测结果表明:虽然不同类别的月度景气变量在不同预测期的预测结果存在一定的差异,但实时预报、短期预测,以及组合预测结果均表明混频动态向量自回归预测模型对我国季度实际GDP增长率的实时预报和短期预测具有精确性、有效性与适用性.  相似文献   
186.
Several researchers have proposed solutions to control type I error rate in sequential designs. The use of Bayesian sequential design becomes more common; however, these designs are subject to inflation of the type I error rate. We propose a Bayesian sequential design for binary outcome using an alpha‐spending function to control the overall type I error rate. Algorithms are presented for calculating critical values and power for the proposed designs. We also propose a new stopping rule for futility. Sensitivity analysis is implemented for assessing the effects of varying the parameters of the prior distribution and maximum total sample size on critical values. Alpha‐spending functions are compared using power and actual sample size through simulations. Further simulations show that, when total sample size is fixed, the proposed design has greater power than the traditional Bayesian sequential design, which sets equal stopping bounds at all interim analyses. We also find that the proposed design with the new stopping for futility rule results in greater power and can stop earlier with a smaller actual sample size, compared with the traditional stopping rule for futility when all other conditions are held constant. Finally, we apply the proposed method to a real data set and compare the results with traditional designs.  相似文献   
187.
李原  韩朝怡 《统计与决策》2017,(13):118-124
文章利用国际货币基金组织(IMF)公布的各国(地区)进出口数据,编制了2015年全球商品流量表(G-CFM),描绘了国家(地区)间商品贸易网络关系,采用网络分析的方法对全球商品贸易格局进行了分析,发现了在全球商品贸易中以美、中、德为中心,世界各国紧密交织的网络特征,最后用投入产出方法分析了中国大陆的贸易影响力,测算了中国大陆进出口贸易对不同国家(地区)以及对全球的影响.  相似文献   
188.
Within the past few decades, there has been an explosion of articles examining “gay identity.” Yet, much of this work continues to center on the experiences of gay White men or fail to adequately examine the process of identity development, even when “identity” is central to the discussion. This review outlines 4 theoretical perspectives used to explore gay men of color and identity development. Taken together, these 4 perspectives can offer a rich opportunity to explore the ways that gay men of color come to develop an identity that simultaneously addresses their racial and sexual identities. I argue that examining identity development among gay men of color can help sociology better understand the identity process and provide new insights into examining intersectionality by demonstrating that identities are not only intersectional but also contextual.  相似文献   
189.
A preliminary test estimator of variance in the bivariate normal distribution is proposed after the Pitman–Morgan test of homogeneity of two variances. The bias and mean square error of the estimator are derived. The relative efficiency (RE) of the preliminary test estimator is studied. Computations and 3D graphs of RE for different parameters are analyzed. In order to get the maximum RE, recommendations of the significance level for the preliminary test are given for various sample sizes by using the max–min criterion.  相似文献   
190.
This article contains two distinct messages. First, when jurisdictions compete in two independent strategic variables, the decision to coordinate on one variable (a tax rate) induces a carry‐over effect on the unconstrained instrument (infrastructure expenditures). Consequently, classical results of the tax coordination literature may be qualified. A second message is that the relative flexibility of the strategic instruments, which may depend on the time horizon of the decision making, does matter. In particular, tax coordination is more likely to be detrimental (in terms of revenue and/or welfare) when countries can compete simultaneously in taxes and infrastructure, rather than sequentially. The reason is that simultaneity eliminates strategic effects between tax and nontax instruments. (JEL H21, H87, H73, F21, C72)  相似文献   
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