传统科技视野下的恐怖主义及其应对

科学技术的发展及其被恶意运用,使当代的恐怖主义活动变得更加复杂多样和令人恐慌.掌握和使用高科技的超级恐怖主义组织的确存在,但对于一般恐怖分子而言,高科技的运用还不大现实.多数情况下,都是传统通用科技引导着普通的恐怖主义活动.恐怖活动与传统通用科技相伴发展的历史事实,表明传统通用科技对恐怖主义与反击恐怖主义双重力量扩张所起的作用,具体体现在武器技术、交通运输和通信技术的应用等方面.科学技术既是恐怖主义盛行的因素,也是恐怖主义的克星,运用高科技手段反击恐怖主义也是我们的必然选择.     

A Risk-Based Method for Modeling Traffic Fatalities

We describe a risk-based analytical framework for estimating traffic fatalities that combines the probability of a crash and the probability of fatality in the event of a crash. As an illustrative application, we use the methodology to explore the role of vehicle mix and vehicle prevalence on long-run fatality trends for a range of transportation growth scenarios that may be relevant to developing societies. We assume crash rates between different road users are proportional to their roadway use and estimate case fatality ratios (CFRs) for the different vehicle-vehicle and vehicle-pedestrian combinations. We find that in the absence of road safety interventions, the historical trend of initially rising and then falling fatalities observed in industrialized nations occurred only if motorization was through car ownership. In all other cases studied (scenarios dominated by scooter use, bus use, and mixed use), traffic fatalities rose monotonically. Fatalities per vehicle had a falling trend similar to that observed in historical data from industrialized nations. Regional adaptations of the model validated with local data can be used to evaluate the impacts of transportation planning and safety interventions, such as helmets, seat belts, and enforcement of traffic laws, on traffic fatalities.     

Discrete time modelling of disease incidence time series by using Markov chain Monte Carlo methods

Summary.  A stochastic discrete time version of the susceptible–infected–recovered model for infectious diseases is developed. Disease is transmitted within and between communities when infected and susceptible individuals interact. Markov chain Monte Carlo methods are used to make inference about these unobserved populations and the unknown parameters of interest. The algorithm is designed specifically for modelling time series of reported measles cases although it can be adapted for other infectious diseases with permanent immunity. The application to observed measles incidence series motivates extensions to incorporate age structure as well as spatial epidemic coupling between communities.     

我国交通经济转型期的交通政策

我国交通经济已经正处在从初步运输化向完善运输化转变的重要时期，交通经　济发展表现出新的矛盾。本文认为工国交通政策的目标和内容缺乏明确性和完整性。现阶　段我国交通　政策主要应围绕着交通市场政策、交通投资政策、交通调整政策和交通补助政策等内容展开　，建立我国新型的交通政策体系。     

我国城市交通可持续发展初探

本文首先给出了城市交通发展与城市交通环境影响互动机理的计算公式 ,在此基础上提出了城市交通环境损害治理的完整逻辑体系 ,然后结合我国的实际情况 ,从环境经济与技术经济的角度出发 ,就我国城市交通的可持续发展发表了相关看法。     

ELICITING A DIRECTED ACYCLIC GRAPH FOR A MULTIVARIATE TIME SERIES OF VEHICLE COUNTS IN A TRAFFIC NETWORK

The problem of modelling multivariate time series of vehicle counts in traffic networks is considered. It is proposed to use a model called the linear multiregression dynamic model (LMDM). The LMDM is a multivariate Bayesian dynamic model which uses any conditional independence and causal structure across the time series to break down the complex multivariate model into simpler univariate dynamic linear models. The conditional independence and causal structure in the time series can be represented by a directed acyclic graph (DAG). The DAG not only gives a useful pictorial representation of the multivariate structure, but it is also used to build the LMDM. Therefore, eliciting a DAG which gives a realistic representation of the series is a crucial part of the modelling process. A DAG is elicited for the multivariate time series of hourly vehicle counts at the junction of three major roads in the UK. A flow diagram is introduced to give a pictorial representation of the possible vehicle routes through the network. It is shown how this flow diagram, together with a map of the network, can suggest a DAG for the time series suitable for use with an LMDM.     

Improved Monte Carlo inference for models with additive error

Some statistical models defined in terms of a generating stochastic mechanism have intractable distribution theory, which renders parameter estimation difficult. However, a Monte Carlo estimate of the log-likelihood surface for such a model can be obtained via computation of nonparametric density estimates from simulated realizations of the model. Unfortunately, the bias inherent in density estimation can cause bias in the resulting log-likelihood estimate that alters the location of its maximizer. In this paper a methodology for radically reducing this bias is developed for models with an additive error component. An illustrative example involving a stochastic model of molecular fragmentation and measurement is given.     

烟台市长江路交通信号线协调控制的设计思路与方法

简述了把传统的解析计算法和计算机仿真优化法相结合的线协调控制综合设计方法及设计流程.以烟台市开发区主干道长江路线协调控制为例给出了具体的设计方案,对设计方案进行了评价.     

Pathways between education and health: a causal modelling approach

Summary.  The association of poor education and poor health has been consistently observed in many studies and in various countries. Thus far, studies examining the mechanisms underlying this association have looked at only a limited set of potential pathways. This study simultaneously examines six distinctive pathways, which have been hypothesized to link education and health and found support from previous studies. A causal analysis of education and health was performed using structural equation models. Data were used from six phases of the National Child Development Study, which is based on following up an initial sample of 17416 children who were born in 1958. The association between education and health appears to be explained by a combination of mechanisms: adolescent health and adult health behaviours for men and women, adult social class among men and parental social class among women. We conclude that improvements in population educational attainment may not automatically lead to improvements in population health, and that health policies for improving health and reducing health inequalities need to target specific causal pathways.     

Any complete preference structure without circuit admits an interval representation

This article proves that all complete preference structures where the strict preference relation (P) has no circuit admit a representation by intervals of the real line; the rule for deciding whether an interval is indifferent or preferred to another is less straightforward than for interval orders: strict preference is indeed compatible with a certain degree of overlapping of intervals, the allowed degree being specified by means of a so-called tolerance function.