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291.
首都第二机场的建设已成定局,由此而引起的大量人才需求是各层次学校所关注的焦点。北京经济管理职业学院是否能抓住这一得天独厚的机遇,将是未来几年对北京经济管理职业学院的考验,因此根据近几年来对首都二机场建设的资料的收集和调研,了解了机场建设对航空人才的需求,为学院的发展提供了建设性的参考性意见。  相似文献   
292.
This paper considers the tail asymptotic of discounted aggregate claims with compound dependence under risky investment. The price of risky investment is modeled by a geometric Lévy process, while claims are modeled by a one-sided linear process whose innovations further obeying a so-called upper tail asymptotic independence. When the innovations are heavy tailed, we derive some uniform asymptotic formulas. The results show that the linear dependence has significant impact on the tail asymptotic of discounted aggregate claims but the upper tail asymptotic independence is negligible.  相似文献   
293.
无人机从20世纪初初具雏形到今天运用于许多领域,其军事化发展进程总体上看从未停止。国际法上虽然承认军事化无人机存在的合法性,但当它被用于诉诸战争权的行使时却依然存在争议,并且自主无人机需要国际人道法考量。军事化无人机必须在国际法框架下行使。在用于诉诸战争权时,应该谨慎解释"国家同意""国家同意的限制""必要性""相称性"等概念,并且严格区分普通无人机与自主无人机对国际人道主义法的挑战,让军事化无人机可以更加规范地被利用。  相似文献   
294.
Abstract

On the basis of Wang and Cheng (J. Math. Anal. Appl. 384 (2011) 597–606), this paper further investigates elementary renewal theorems for counting processes generated by random walks with widely orthant dependent increments. The obtained results improve the corresponding ones of the above-mentioned paper mainly in the sense of weakening the moment conditions on the positive parts of the increments. Meanwhile, a revised version of strong law of large numbers for random walks with widely orthant dependent increments is established, which improves Theorem 1.4 of Wang and Cheng (2011 Wang, Y., and D. Cheng. 2011. Basic renewal theorems for a random walk with widely dependent increments and their applications. Journal of Mathematical Analysis and Applications 384 (2):597606. doi:10.1016/j.jmaa.2011.06.010.[Crossref], [Web of Science ®] [Google Scholar]) by enlarging the regions of dominating coefficients. Finally, by using the above results, some precise large deviation results for a nonstandard renewal risk model are established, in which the innovations are widely orthant dependent random variables with common heavy tails, and the inter-arrival times are also widely orthant dependent.  相似文献   
295.
This paper studies the likelihood ratio ordering of parallel systems under multiple-outlier models. We introduce a partial order, the so-called θ-order, and show that the θ-order between the parameter vectors of the parallel systems implies the likelihood ratio order between the systems.  相似文献   
296.
The generalized linear model (GLM) is a class of regression models where the means of the response variables and the linear predictors are joined through a link function. Standard GLM assumes the link function is fixed, and one can form more flexible GLM by either estimating the flexible link function from a parametric family of link functions or estimating it nonparametically. In this paper, we propose a new algorithm that uses P-spline for nonparametrically estimating the link function which is guaranteed to be monotone. It is equivalent to fit the generalized single index model with monotonicity constraint. We also conduct extensive simulation studies to compare our nonparametric approach for estimating link function with various parametric approaches, including traditional logit, probit and robit link functions, and two recently developed link functions, the generalized extreme value link and the symmetric power logit link. The simulation study shows that the link function estimated nonparametrically by our proposed algorithm performs well under a wide range of different true link functions and outperforms parametric approaches when they are misspecified. A real data example is used to illustrate the results.  相似文献   
297.
298.
马是游牧文明的标志性核心载体之一。马的驯化,特别是马的承骑不仅造就了游牧文明,推动草原文化走向新的发展阶段,也对整个人类社会的政治、经济、军事、交通、商贸和文化交流产生过深远的影响。游牧形态的形成与发展空前加强和提升了草原文化的内聚力、外张力,出现很多彼此联系紧密、特征相近的游牧民族、游牧帝国,将亚欧草原变成游牧文明天下,对世界的民族、文化格局带来深刻变化。  相似文献   
299.
Cities evolution tree and applications to predicting urban growth   总被引:4,自引:0,他引:4  
China’s unprecedented urbanization and economic modernization have brought about significant growth and land use changes in cities and their surroundings. Traditional analyses of the relationship between urbanization and land use change have not fully incorporated important factors like city function or developmental stage. We define and apply a new visualization and analysis tool—an evolution tree—showing how an understanding of evolutionary pathways taken by growing cities contributes to visualization and forecasting of urban development and spatial expansion. We clustered 253 Chinese cities by type and developmental stage, arranging them in a “tree” structure, with types grouped as branches and leaf position along branches reflecting developmental stage. Urban growth rates are higher for business-oriented, manufacturing-oriented, and functionally comprehensive cities than for those oriented toward tourism. Extent of spatial growth is dominated by city type and developmental stage. Cities evolve along typical pathways, punctuated by occasional leap developments across functional types.  相似文献   
300.
王健 《今日辽宁》2014,(1):50-51
笔墨语言的表达能力,对于一个精确表达思想的人是十分重要的。对王宁来说,他的书法、篆刻、诗词、绘画等创作,能将笔墨经营出无限丰富的层次来,并将多种表现手法的试验,进一步介入到当代书画艺术发展的主流上来,这是非常难得的。王宁从中国历代经典的书法作品中,采足了雄健、宽博、飘逸、清净之气,乃至篇幅不论大小,同样使我们体会到宏大的精神境界和超于物象之上的精神表达。  相似文献   
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