环境匮乏、社会适应性和紧急冲突:霍马-迪克逊环境安全研究述评

环境安全是当代可持续发展的重要议题。在建构环境匮乏、社会适应性和紧急冲突的因果联系过程中,霍马—迪克逊(Homer-D ixon)探讨了环境安全的本体论与方法论问题,对发展中国家的环境安全问题进行了经验研究,并且建立了较为完整的环境安全理论体系。他的研究有一些启发意义,当然也存在一些不足。     

信息化环境下审计内容与技术方法探讨

随着被审计单位各种信息系统的应用和会计信息化环境的逐渐形成,审计的内容与技术方法也发生了巨大的变化,审计内容转变为会计信息系统安全性审计和电子财务数据准确性审计两个方面。对会计系统安全性审计主要包括物理安全、技术安全和组织与管理安全几个方面;对电子财务数据准确性的审计一般分为数据采集、转换、清理与分析四个阶段。这些技术方法既有传统审计技术方法在信息化环境下的延伸,也有各种特定的IT审计技术。从长远上看,以智能审计专家知识库等IT审计技术将成为信息化环境下审计技术方法的未来发展趋势,对其方法进行研究具有很大的理论价值和现实意义。     

韩国人口老龄化与老年人社会保障

随着近几十年生育率的持续下降及平均寿命的不断提高 ,韩国人口逐渐出现了老龄化趋势。到下世纪初韩国人口老龄化进程将进一步加快。韩国人口老龄化的显著特征 ,就是在急剧的现代化过程中 ,还没来得及健全老年人社会保障、福利、医疗、保健等制度的情况下将迎来迅速的人口老龄化 ,从而使全社会面临着不断增长的老年人福利、医疗、保健需求     

A class of weighted dependence measures for bivariate failure time data

This paper considers a class of summary measures of the dependence between a pair of failure time variables over a finite follow-up region. The class consists of measures that are weighted averages of local dependence measures, and includes the cross-ratio-measure and finite region version of Kendall's τ; recently proposed by the authors. Two new special cases are identified that can avoid the need to estimate the bivariate survivor function and that admit explicit variance estimators. Nonparametric estimators of such dependence measures are proposed and are shown to be consistent and asymptotically normal with variances that can be consistently estimated. Properties of selected estimators are evaluated in a simulation study, and the method is illustrated through an analysis of Australian Twin Study data.     

Generalized estimator of population mean by using conventional and non-conventional measures in the presence of measurement errors

In survey research, it is assumed that reported response by the individual is correct. However, given the issues of prestige bias, self-respect, respondent's reported data often produces estimated values which are highly deviated from the true values. This causes measurement error (ME) to be present in the sample estimates. In this article, the estimation of population mean in the presence of measurement error using information on a single auxiliary variable is studied. A generalized estimator of population mean is proposed. The class of estimators is obtained by using some conventional and non-conventional measures. Simulation and numerical study is also conducted to assess the performance of estimators in the presence and absence of measurement error.     

On comparing,classifying and clustering several dependent regression models

Classifying several regression models fitted on a dataset is one of the most problems in data analysis. In other words, scientists are interested in comparing several regression models that can be used for a dataset. In this paper, an approach will be used to compare and classify several dependent regression models. Then the performance of the proposed method is investigated using simulation study and real example.     

China’s flexible overseas food strategy: food trade and agricultural investment between Southeast Asia and China in 1990–2015

Using the UN Comtrade database and multiple sources of agricultural investment data, this paper outlines the emerging patterns of food trade and agricultural investment between Southeast Asian countries and China. The paper shows that China has adopted a flexible overseas food strategy. First, China has increased food export and shifted its food trade with Southeast Asia from a dependent relationship towards a complementary relationship at the regional level in recent years. Second, China tends to adapt to the existing conditions of food production and trade in Southeast Asian countries instead of fundamentally altering them. Finally, Chinese overseas agricultural investment is less driven by domestic food demand but more oriented for profit making, and this gives it flexibility in diversifying investment. An adequate understanding of China’s flexible food strategy in bilateral and multilateral relationships holds implications for global food security.     

单窃听双跳协作网络的中继选择方案及其性能分析

研究了安全通信意义下,单向译码转发（decode-and-forward,DF）协作无线网络的中继选择问题。针对窃听者既能获得信源发出的信号,又能窃取中继节点转发数据的通信系统,提出了3种中继选择方案来对抗窃听者,增强系统物理层安全性。其中,方案一选择到窃听者信噪比（signal-to-noise ratio,SNR）最小的中继节点;方案二为最大最小（max-min）选择方案,即选择信源到中继节点和中继节点到信宿的较差信噪比中最大值所对应的中继节点;方案三根据窃听信道和主信道的瞬时信道状态信息（channel state information,CSI）选择使得窃听网络有最大保密容量的中继节点。在对各方案的性能分析过程中,得到了各中继选择方案拦截概率的闭式表示,进一步对拦截概率作渐近分析,获得了各中继选择方案的分集阶数。具体地,方案一的分集阶数为1,另外2个中继选择方案的分集阶数均为中继节点个数M。数值结果验证了理论分析得到的结论。     

计算机无线网络安全技术探析

近年来随着无线网络的快速发展,无线网络替代传统有线网络的趋势日益明显。与此同时,无线网络的安全机制也需要得到同步完善,从而进一步实现人们安全通信的要求。论述了计算机无线网络安全所面临的主要问题,提出了解决这些无线网络安全问题的措施。     

Trauma management: Chernobyl in Belarus and Ukraine

Although the Chernobyl nuclear disaster happened in the Soviet Union in 1986, we still do not know how the most affected states – Ukraine and Belarus – have managed this tragedy since independence. Drawing on the concept of cultural trauma, this article compares Chernobyl narratives in Belarus and Ukraine over the past 28 years. It shows that national narratives of Chernobyl differ, representing the varying ways in which the state overcomes trauma. Our understanding of post‐communist transformations can be improved by analysing trauma management narratives and their importance for new national identity construction. These narratives also bring new insights to our vision of cultural trauma by linking it to ontological insecurity. The article demonstrates how the state can become an arena of trauma process as it commands material and symbolic resources to deal with trauma. In general, it contributes to a better understanding of how the same traumatic event can become a source of solidarity in one community, but a source of hostility in another.