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961.
In the article, the exponential inequalities for sums of unbounded ?-mixing sequence are given, which generalize the corresponding one for independent and identically distributed random variables. As applications, the strong law of large numbers and strong growth rate for ?-mixing random variables are obtained.  相似文献   
962.
Crowd density is a key factor that influences the moving characteristics of a large group of people during a large‐scale evacuation. In this article, the macro features of crowd flow and subsequent rescue strategies were considered, and a series of characteristic crowd densities that affect large‐scale people movement, as well as the maximum bearing density when the crowd is extremely congested, were analyzed. On the basis of characteristic crowd densities, the queuing theory was applied to simulate crowd movement. Accordingly, the moving characteristics of the crowd and the effects of typical crowd density—which is viewed as the representation of the crowd's arrival intensity in front of the evacuation passageways—on rescue strategies was studied. Furthermore, a “risk axle of crowd density” is proposed to determine the efficiency of rescue strategies in a large‐scale evacuation, i.e., whether the rescue strategies are able to effectively maintain or improve evacuation efficiency. Finally, through some rational hypotheses for the value of evacuation risk, a three‐dimensional distribution of the evacuation risk is established to illustrate the risk axle of crowd density. This work aims to make some macro, but original, analysis on the risk of large‐scale crowd evacuation from the perspective of the efficiency of rescue strategies.  相似文献   
963.
以坐落在俄罗斯远东地区符拉迪沃斯托克市的轻质钢桥为研究主体,利用现场实测及理论分析对轻质钢桥进行动力学参数评估。结果表明:实际测得振动周期与理论计算值基本吻合,而轻质钢桥的自振周期不符合俄罗斯桥梁设计规范。为改善轻质钢桥的动力特性,提出了采用加铺混凝土方案和准确评估轻质钢桥的动力学特性需要全面考虑结构的组成细节,并建立有限元模型的必要性,其结果具有一定的理论意义和工程实践应用价值。  相似文献   
964.
In this paper, the strong laws of large numbers for maximum value of weighted sums of extended negatively dependent random variables are obtained, which improve and extend the corresponding ones for independent random variables and some dependent random variables.  相似文献   
965.
966.
以下承式铁路钢桁梁为研究对象,采用理论分析与现场试验相结合的方法,对重载列车作用下64 m单线简支、64 m双线简支和64 m双线连续下承式钢桁梁各杆件的力学特性进行分析。得知,中 活载作用下双线简支下承式钢桁梁重车侧结构杆件挠度和应力最大,单线简支下承式钢桁梁次之,双线连续下承式钢桁梁最小;运营重载列车作用下双线连续下承式钢桁梁横向振幅和横向加速度最小,双线简支下承式钢桁梁桥次之,单线简支下承式钢桁梁桥最大。  相似文献   
967.
This paper is concerned with estimation of location and scale parameters of an exponential distribution when the location parameter is bounded above by a known constant. We propose estimators which are better than the standard estimators in the unrestricted case with respect to the suitable choice of LINEX loss. The admissibility of the modified Pitman estimators with respect to the LINEX loss is proved. Finally the theory developed is applied to the problem of estimating the location and scale parameters of two exponential distributions when the location parameters are ordered.  相似文献   
968.
With a parametric model, a measure of departure for an interest parameter is often easily constructed but frequently depends in distribution on nuisance parameters; the elimination of such nuisance parameter effects is a central problem of statistical inference. Fraser & Wong (1993) proposed a nuisance-averaging or approximate Studentization method for eliminating the nuisance parameter effects. They showed that, for many standard problems where an exact answer is available, the averaging method reproduces the exact answer. Also they showed that, if the exact answer is unavailable, as say in the gamma-mean problem, the averaging method provides a simple approximation which is very close to that obtained from third order asymptotic theory. The general asymptotic accuracy, however, of the method has not been examined. In this paper, we show in a general asymptotic context that the averaging method is asymptotically a second order procedure for eliminating the effects of nuisance parameters.  相似文献   
969.
In this paper, we discuss the problem of estimating reliability (R) of a component based on maximum likelihood estimators (MLEs). The reliability of a component is given byR=P[Y<X]. Here X is a random strength of a component subjected to a random stress(Y) and (X,Y) follow a bivariate pareto(BVP) distribution. We obtain an asymptotic normal(AN) distribution of MLE of the reliability(R).  相似文献   
970.
党的“十八大”提出建设“美丽中国”的宏伟蓝图,鼓励和支持休闲设施供给建设,加之国民收入持续提高,节假时间增加,休闲旅游发展迎来新时代.在此时代背景下,结合巢湖创建环巢湖国家旅游休闲区的良好契机,充分依托环巢湖滨湖地区优越的自然及人文资源,通过渐进有序、文旅融合的空间总体规划,将环巢湖滨湖岸线打造成集自然生态景观、休闲娱乐、公共服务、文化展示于一体的滨湖带状休闲空间,使其成为环巢湖国家旅游休闲区的核心引力区域,为城市特大湖泊岸线相关保护和开发建设探索出可供借鉴的有效路径.  相似文献   
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