二元负相关性及各水平之问的关系

多元随机变量相关性在许多方面引起关注，本文提出较强的二元随机变量之间各水平正相关及负相关的定义和相互关系。     

二元负相关性及各水平之间的关系

多元随机变量相关性在许多方面引起关注,本文提出较强的二元随机变量之间各水平正相关及负相关的定义和相互关系.     

非线性消亡过程的二元相关性

多元随机变量相关性在许多方面引起关注,本文在二元随机变量之间各水平正相关及负相关的定义和相互关系的基础上讨论非线性纯消亡过程的相关水平.     

Gauss随机变量产生方法的比较研究

在通信系统仿真中,Gauss随机变量是最重要也是最常用到的随机变量。根据Gauss随机变量产生的基本原理,结合中心极限定理、坐标转换和概率分布的基本知识,分析了产生Gauss随机变量的三类方法,即12求和法、Box-Mull-er法和极坐标法,实现了Gauss随机变量的产生,比较了三种方法和直接使用函数产生Gauss随机变量的性能,提出了检验Gauss随机变量的易实现的三个参数-相对集中度、宽度对称度和相对宽度对称度,分析研究得出：12求和法产生的Gauss随机变量相对集中,Box-Muller法的统计特性、对称性等综合性能更优的结论。     

结构可靠度分析中随机变量间相关系数的特性

在结构可靠度分析中,经常要把随机变量通过当量正态化变换为标准正态随机变量.随机变量的变换过程,包括线性函数变换和非线性函数变换.为了研究随机变量间相关系数的变化规律,利用概率论的基本思想分析得出,经过线性变换后变量之间相关系数保持绝对值不变,非线性变换后保持随机变量之间相关系数近似不变.因此在结构可靠度分析中,变量之间相关系数近似保持相等,其误差随变换的非线性程度增高而增大.     

由离散边缘分布律求联合分布律的计算法

在作交通运输计划时,常利用运筹学中的西北角法制定最优运输方案.本文讨论了这一方法与离散型随机变量之间的关系,证明了对任意两个给定的离散型随机变量,可利用西北角法求出一个二维离散型随机变量使其边缘分布律为已知的两个随机变量的分布律.     

博弈系统中任意随机变量序列关于乘积分布的一类强极限定理

引进似然比作为任意随机变量序列相对于服从二项分布的独立随机变量序列偏差的一种度量,并通过限制似然比给出了样本空间的一个子集,在此子集上得到了博弈系统中任意随机变量序列关于乘积二项分布的一类强极限定理,作为推论得到了博弈系统中服从二项分布的独立随机变量序列的一族强大数定理。     

随机选择系统中任意随机变量序列关于乘积分布的一类强偏差定理

通过引进极限对数似然比的概念,作为任意随机变量序列相对于服从二项分布的独立随机变量序列的分布偏差的一种度量,通过限制似然比给出了样本空间的一个子集,在此子集上得到了赌博系统(又称随机选择系统)中任意随机变量序列的一类用不等式表示的强极限定理,作为推论得到了任意随机变量序列关于二项乘积分布的强偏差定理以及服从二项分布的独立随机变量序列的一族强大数定理.     

任意随机变量序列关于广义随机选择系统的若干极限性质

采用鞅方法研究了对任意随机变量序列关于广义随机选择普遍成立的一类强极限定理,并作为推论得到了m阶马氏过程,鞅序列,鞅差序列,独立随机变量序列的一类强极限定理.把赌博系统的随机变换概念推广到任意随机变量序列,得到了任意随机变量序列随机选择与公平比的若干极限定理.     

Cantor型随机变量序列强极限定理的研究

研究了对任意Cantor型随机变量序列普遍成立的一类强大数定理。证明中利用条件期望的概念,采用测度的网微分法并运用纯分析运算得出结论,由推论得到随机变量序列已有的经典强大数定律以及对任意随机变量序列普遍成立的强大数定律。     

Empirical approaches to combining revealed and stated preference data: Some recent developments with reference to urban mode choice

This paper replaces the nested logit ‘trick’ used in estimation of a modal choice model, when stated preference (SP) and revealed preference (RP) data are pooled, with an error component mixed logit model that can (i) relax the IID condition attached to subsets of alternatives in nested logit models, (ii) accommodate correlated observations, and (iii) reveal the relevant scale parameter for subsets of alternatives. Such a model can also incorporate state dependence between data types and preference heterogeneity on observed attributes. An example of choice among bus, train and car modes illustrates the difference in empirical evidence, especially elasticity outputs.     

Hub dependence in constrained economies: the case of North Korea

While the geographical and economic factors concerning the development of hub ports are widely described by a variety of scholars and professionals, there is no recognized methodology measuring the hub dependence of a given port, region, or country. Based on a 20-year database of vessel movements, this paper proposes a methodology measuring hub dependence. North Korea offers a good case of a constrained economy facing dramatic internal and external pressures. Notably, the weight and geographical extent of its maritime connections are worth analysing because of its contrasted evolution from Soviet influence, geopolitical isolation, and growing trade due to economic reforms and increased foreign investments. The main results of this study show the spatial shift from long-distance calls to feeder calls: global foreland contraction, regionalization within Northeast Asia, and traffic concentration upon closest hubs of which South Korean ports. We conclude that hub dependence is a combination of local constraints and trade growth. The political implications of this phenomenon are explored, and a spatial model of hub dependence is proposed.     

On the accuracy of fracture estimation in collision analysis of ship and offshore structures

This paper discusses the fracture response in a collision scenario together with the discretization of the model, and it compares various approaches suggested by current design rules and proposed by researchers using a validation approach with different model scales; including material tests, indentation experiments and simulations of an actual full-scale collision event. Calibration of the fracture criteria is performed based only on data that can safely be assumed to be available in a design situation, namely, those from a uniaxial tensile test. This approach reveals the behavior of each criterion as it would be in a design situation and avoids the possibility of calibration toward a known solution. The robustness of the fracture criteria, i.e., their ability to simulate fracture given varying stress states and mesh sizes, are investigated based on simulations of experiments. The statistical variations for the various criteria are shown.     

一种基于粗糙集的决策树生成算法

针对决策树的构造和修剪通常不能同时进行所产生的效率低下的问题，提出了基于粗糙集理论中知识依赖性的决策树构造方法。利用优先策略，将知识依赖性同时作为属性约简和建树的准则，在决策树预修剪的同时进行节点生成，大大提高了决策树构造的效率。使用Fisher＇s iris数据集对琏于粗糙集理论中知识依赖性的决策树生成算法和用回归拟合方法的决策树生成算法进行比较。实验结果表明，前者的分类精度和决策树模型的复杂程度要明显优于后者。     

贝叶斯与遗传神经网络相融合的柴油机故障诊断研究

利用小波包分解提取缸盖振动信号的特征向量,提出选择因子对改进误差反向传播(BP)神经网络和超1-依赖贝叶斯算法的诊断结果进行融合,克服贝叶斯和神经网络的不足。通过在WD615柴油机上的实验检测,证明了该方法的有效性。     

Using Socioeconomic and Fisheries Involvement Indices to Understand Alaska Fishing Community Well-Being

Over recent years, fisheries managers have been going through a paradigm shift to prioritize ecosystem-based management. With this comes an increasing need to better understand the impacts of fisheries management decisions on the social well-being and sustainability of fishing communities. This article summarizes research aimed at using secondary data to develop socioeconomic and fisheries involvement indices to measure objective fishing community well-being in Alaska. Data from more than 300 communities in Alaska were used to create a database of socioeconomic and fisheries involvement indices of objective well-being and adaptability for Alaska communities dependent on marine resources. Each index was developed using a principal components factor analysis to assess the relative position of each community compared to all other communities in Alaska. We find that creating performance measures, such as the indices presented here, provides a useful way to track the status of socioeconomic conditions and fisheries involvement by communities over time.     

企业发展"以人为本"

提出了人是企业经营的主体,是确保竞争优势地位中决定性的因素。企业要科学、健康、快速的发展,必须以人为本,以人为根本依靠,以满足人的正当需要、实现人的全面发展为发展目标。     

Seamen, drink and social structure

Drinking among seafarers is an age-old and insufficiently studied problem. This paper is not concerned with alcoholism but with normal social drinking, its effects on suicide and accident rates, and its considerable value as an integrating factor in shipboard life. The author distinguishes sharply between sea-drinking and port-drinking and summarizes the research that relates personality traits, particularly dependence, to the use and abuse of alcohol.     

基于WSEIAC模型的某炮兵指挥控制系统效能分析研究

基于WSEIAC模型的炮兵指挥控制系统效能分析模型,通过可用度向量、可信赖矩阵和能力向量三者的函数建立基本数学计算模型,再根据武器系统在执行任务前,须经过若干个可靠性指标不同的过程得出武器系统在执行任务时的系统效能。该模型的求解涉及炮兵营系统的初始可用性向量、各节点的可信赖矩阵和可用度、火炮系统能力向量、炮兵系统能力向量的计算。     

Seamen,drink and social structure

Drinking among seafarers is an age-old and insufficiently studied problem. This paper is not concerned with alcoholism but with normal social drinking, its effects on suicide and accident rates, and its considerable value as an integrating factor in shipboard life. The author distinguishes sharply between sea-drinking and port-drinking and summarizes the research that relates personality traits, particularly dependence, to the use and abuse of alcohol.