The Multiscale Importance of Road Segments in a Network Disruption Scenario: A Risk‐Based Approach

This article addresses the problem of the multiscale importance of road networks, with the aim of helping to establish a more resilient network in the event of a road disruption scenario. A new model for identifying the most important roads is described and applied on a local and regional scale. The work presented here represents a step forward, since it focuses on the interaction between identifying the most important roads in a network that connect people and health services, the specificity of the natural hazards that threaten the normal functioning of the network, and an assessment of the consequences of three real‐world interruptions from a multiscale perspective. The case studies concern three different past events: road interruptions due to a flood, a forest fire, and a mass movement. On the basis of the results obtained, it is possible to establish the roads for which risk management should be a priority. The multiscale perspective shows that in a road interruption the regional system may have the capacity to reorganize itself, although the interruption may have consequences for local dynamics. Coordination between local and regional scales is therefore important. The model proposed here allows for the scaling of emergency response facilities and human and physical resources. It represents an innovative approach to defining priorities, not only in the prevention phase but also in terms of the response to natural disasters, such as awareness of the consequences of road disruption for the rescue services sent out to local communities.     

Estimating mixtures of normal distributions via empirical characteristic function

This paper uses the empirical characteristic function (ECF) procedure to estimate the parameters of mixtures of normal distributions. Since the characteristic function is uniformly bounded, the procedure gives estimates that are numerically stable. It is shown that, using Monte Carlo simulation, the finite sample properties of th ECF estimator are very good, even in the case where the popular maximum likelihood estimator fails to exist. An empirical application is illustrated using the monthl excess return of the Nyse value-weighted index.     

广州驻防八旗生计问题探析

摘要：满清定都北京以后,八旗军民合一的体制被打破,清政府为维护政权的稳固,分派八旗军在全国多处驻防。广州八旗在 驻防初期,有钱粮制度作保障,且旗民人口较少,因此,旗民生活较为宽裕,但随着清政府财政的枯竭,广州八旗旗民人口的增 长,广州驻防八旗旗民面临着严峻的生计问题,虽然广州采取了四项主要措施来解决旗民的生计问题,但这些措施对于多数生 计维艰的八旗旗民来说,仍是杯水车薪,最终广州八旗旗民突破了八旗驻防制度的种种束缚,开始自谋生路     

基于多阶段随机规划模型的国债动态积极投资策略

本文提出国债组合投资的多阶段随机规划模型,导出基于未来利率市场不确定信息的具备动态调整特点的国债组合主动投资策略。该模型采用基于利率水平、斜率和曲率"三位一体"的离散情景树刻画未来利率期限结构动态演化过程,其中特别考虑了广义货币供给变动的影响;通过最小化国债组合收益的条件风险价值,对国债组合进行主动动态调整;同时兼顾国债投资安全性、流动性和收益性等要求,实现了国债组合投资管理中利率风险规避和收益能力的有效匹配。实证研究表明,与传统久期配比免疫模型相比,该模型确定的最优策略不仅能够为国债组合提供更强的抵御利率风险能力,而且能够稳步提升其收益空间,为金融机构实现国债投资的主动管理提供决策支持。     

语篇构建中的谓词转喻

为有效、合理地解读隐喻,采用事态场境理论对谓词转喻做了初步探讨,并将谓词转喻分为"潜在性代替现实性"及"一般代替具体"两类。谓词转喻作为一种语用转喻构成了语篇中的语用推理图式,其转喻关系的力度直接影响会话双方的语用推理和语境之间的相互作用。     

基于SSM的湖南省入境旅游客源市场结构分析

以2000-2009年湖南省主要入境客源国(地区)入境旅游人次为样本,运用偏离—份额分析法(shift-share method)对湖南省入境旅游客源市场结构进行了分析得出结论:湖南省入境旅游客源市场结构较为合理,市场竞争力强,未来发展前景广阔,但是客源结构也呈现出过度集中化的趋势。对此,应根据各客源市场的不同情况,采取有针对性的措施,以进一步优化湖南省入境旅游客源市场结构。     

The Burr XII System of densities: properties,regression model and applications

We introduce a new class of distributions called the Burr XII system of densities with two extra positive parameters. We provide a comprehensive treatment of some of its mathematical properties. We estimate the model parameters by maximum likelihood. We assess the performance of the maximum likelihood estimators in terms of biases and mean squared errors by means of a simulation study. We also introduce a new family of regression models based on this system of densities. The usefulness of the proposed models is illustrated by means of three real data sets.     

Likelihood inference based on EM algorithm for the destructive length-biased Poisson cure rate model with Weibull lifetime

In this article, we consider the destructive length-biased Poisson cure rate model, proposed by Rodrigues et al., that presents a realistic and interesting interpretation of the biological mechanism for the recurrence of tumor in a competing causes scenario. Assuming the lifetime to follow the Weibull distribution and censoring mechanism to be non-informative, the necessary steps of the EM algorithm for the determination of the MLEs of the model parameters are developed here based on right censored data. The standard errors of the MLEs are obtained by inverting the observed information matrix. A simulation study is then carried out to examine the method of inference developed here. Finally, the proposed methodology is illustrated with a real melanoma dataset.     

江苏省工业碳足迹研究及情景模拟

工业碳足迹是一个复杂的动态的系统, 针对于江苏省工业碳足迹的现状, 利用系统动力学原理, 借助Vensim PLE软件, 建立了江苏省工业碳足迹系统, 把系统分为人口、资源、环境、能源4个子系统, 特别考虑到人均GDP对教育的影响, 通过教育影响技术, 最终影响CO2 排放量。通过历史数据对江苏省工业碳足迹进行仿真, 并从不同经济结构、技术条件、新能源发展情况等角度设置了4种不同的情景, 与原始情景进行比较, 对2005-2020年的工业碳足迹进行分析。从情景模拟结果可以看出:要减少江苏省工业碳足迹, 必须加大力度开发新能源, 调整能源结构, 而技术进步对于工业碳足迹的减少, 效果没有前两者显著。