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31.
This paper studies an M/G/1 clearing queueing system with setup time and multiple vacations, in which all present customers in the system are served simultaneously and breakdowns may occur in busy or setup period. We investigate the stationary distribution of system size and the Laplace–Stieltjes transform of sojourn time. In addition, various performance measures are discussed, such as the mean system size at arbitrary time and the mean length of a vacation circle. Moreover, a cost analysis is carried out for this queueing system. Numerical results are presented to study the sensitivity of the system parameters on the expected cost function and system performances.  相似文献   
32.
国际组织和成员国的法律责任归属问题一直以来都是国际法争论的话题。政府间国际组织作为一类国际法主体,应独立承担法律责任。但在实践中,成员国在执行国际组织决议的过程中往往滥用国际组织法律人格,其行为不仅是国际组织法律人格的体现,还代表了自己的意志,造成法律责任归属不明。以此种争议情形为研究对象,结合1999年的使用武力合法性案,2007年欧洲人权法院的拜拉米案和萨拉马提(Behrami/Saramati)案、阿尔吉达(Al-Jedda)案以及2014年海牙法院关于斯雷布雷尼察(Srebrenica)诉荷兰案的相关判决,借鉴国外学者近几年的相关研究,认为应当坚持国际组织和成员国法律责任的多重归属。围绕责任多重归属原则的确立过程,通过对2011年《国际组织责任条款草案》相关条文的分析,明确了行为归属与责任归属的关系:只有确定行为归属之后,才能确定责任归属;为了最终确定责任的多重归属,提出以有效控制为标准认定行为归属,并明确这种有效控制是对具体行为的事实控制。  相似文献   
33.
利用单期静态博弈分析法、有限期动态博弈分析法和无限期动态博弈分析法对成品油定价机制中寡头厂商的合谋行为进行了分析。研究发现:两家寡头厂商在合谋条件下的收益均高于双方各自独立定产条件下的收益,因此,双方存在进行价格合谋的利益激励。基于此,我国成品油价格形成机制的改革可以考虑采用有限规制等手段。  相似文献   
34.
基于多维效应的能源效率评估使人们在达到经济增长目的的同时兼顾能源安全、竞争力、环境、社会和技术的可持续性。论述能源效率内涵演化发展的路径,在此基础上将能源效率的内涵扩展至多维效应。以非参数DEA(Data Envelopment Analysis)方法为例,研究基于多维效应的能源效率评估方法的演化与发展趋势。研究结果显示:采用DEA方法对基于多维效应的能源效率进行评估的发展趋势主要有以下3点:能源效率的内涵不断延伸;DEA模型向非导向非径向模型转变;能源效率评估的研究维度不断扩展。对多维效应的能源效率综合指标评价体系和评价方法还需做深入研究。  相似文献   
35.
Motivated by several practical issues, we consider the problem of estimating the mean of a p-variate population (not necessarily normal) with unknown finite covariance. A quadratic loss function is used. We give a number of estimators (for the mean) with their loss functions admitting expansions to the order of p ?1/2 as p→∞. These estimators contain Stein's [Inadmissibility of the usual estimator for the mean of a multivariate normal population, in Proceedings of the Third Berkeley Symposium in Mathematical Statistics and Probability, Vol. 1, J. Neyman, ed., University of California Press, Berkeley, 1956, pp. 197–206] estimate as a particular case and also contain ‘multiple shrinkage’ estimates improving on Stein's estimate. Finally, we perform a simulation study to compare the different estimates.  相似文献   
36.
The conceptualizations about children and childhoods enrich our understanding of adult–child interactions, educational practice, policy and child-welfare interventions. This study explored 42 cultural metaphors drawn from diverse socio-economic, geographical and linguistic settings to construct Indian childhoods. The paper reports an interpretative analysis of reconstructions leading to a typology of metaphors-in-use. The conceptual-analytical exercise helped unpack nuances and contextual meanings of metaphors. The paper argues for richness and subtlety in theorising childhoods, which is multilayered, situated and intertwined with contextual issues and tensions. The study offers methodological, pedagogical and conceptual insights and proposes possibilities for using cultural tools into inquiring childhoods.  相似文献   
37.
Business establishment microdata typically are required to satisfy agency-specified edit rules, such as balance equations and linear inequalities. Inevitably some establishments' reported data violate the edit rules. Statistical agencies correct faulty values using a process known as edit-imputation. Business establishment data also must be heavily redacted before being shared with the public; indeed, confidentiality concerns lead many agencies not to share establishment microdata as unrestricted access files. When microdata must be heavily redacted, one approach is to create synthetic data, as done in the U.S. Longitudinal Business Database and the German IAB Establishment Panel. This article presents the first implementation of a fully integrated approach to edit-imputation and data synthesis. We illustrate the approach on data from the U.S. Census of Manufactures and present a variety of evaluations of the utility of the synthetic data. The paper also presents assessments of disclosure risks for several intruder attacks. We find that the synthetic data preserve important distributional features from the post-editing confidential microdata, and have low risks for the various attacks.  相似文献   
38.
PCORnet, the National Patient-Centered Clinical Research Network, seeks to establish a robust national health data network for patient-centered comparative effectiveness research. This article reports the results of a PCORnet survey designed to identify the ethics and regulatory challenges anticipated in network implementation. A 12-item online survey was developed by leadership of the PCORnet Ethics and Regulatory Task Force; responses were collected from the 29 PCORnet networks. The most pressing ethics issues identified related to informed consent, patient engagement, privacy and confidentiality, and data sharing. High priority regulatory issues included IRB coordination, privacy and confidentiality, informed consent, and data sharing. Over 150 IRBs and five different approaches to managing multisite IRB review were identified within PCORnet. Further empirical and scholarly work, as well as practical and policy guidance, is essential if important initiatives that rely on comparative effectiveness research are to move forward.  相似文献   
39.
This article extends the previous research of consecutive attacks strategy by assuming that an attacker observes the outcome of each attack imperfectly. With given probabilities it may wrongly identify a destroyed target as undestroyed, and wrongly identify an undestroyed target as destroyed. The outcome of each attack is determined by a contest success function that depends on the amount of resources allocated by the defender and the attacker to each attack. The article suggests a probabilistic model of the multiple attacks and analyzes how the target destruction probability and the attacker's relative resource expenditure are impacted by the two probabilities of incorrect observation, the attacker's and defender's resource ratio, the contest intensity, the number of attacks, and the resource distribution across attacks. We analyze how the attacker chooses the number of attacks, the attack stopping rule, and the optimal resource distribution across attacks to maximize its utility.  相似文献   
40.
The symmetric treatment of an asymmetric approach to factor analysis is shown to provide accurate communality estimates. In comparison with existing estimates including upper and lower bounds, the present approach is shown to be superior. In one example with known communalities, the present approach perfectly captures those communalities. In two empirical examples, it is shown to produce better communality estimates than any existing method.  相似文献   
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