用改进的灰色关联度分析交通事故成因

改进的灰色关联模型与普通灰色关联模型相比,可以突出关联度的微小变化,且更加科学。通过实例,用改进的灰关联对道路交通事故成因进行了分析,并与普通灰色关联分析进行了比较,发现前者分析结果更具层次性、差异性,更容易识别事故主要、次要和潜在的成因。     

高速公路隧道交通安全问题及对策分析

高速公路隧道交通事故原因复杂且具有多样性。结合隧道特点和交通事故特征,以人-车-路-环境体系为基础,多角度、多方面分析了隧道交通事故发生原因,并提出了合理的解决方案。     

The prigogine-herman kinetic model predicts widely scattered traffic flow data at high concentrations

The classical derivation of a traffic stream model (e.g. speed/concentration relation) from the equilibrium solutions of the Prigogine–Herman kinetic equation invokes the nontrivial assumption that the underlying distribution of desired speeds is nonzero for vanishingly small speeds. In this paper we investigate the situation when this assumption does not hold. It is found that the Prigogine–Herman kinetic equation has a one-parameter family of equilibrium solutions, and hence an associated traffic stream model, only for traffic concentrations below some critical value; at higher concentrations there is a two-parameter family of solutions, and hence a continuum of mean velocities for each concentration. This result holds for both constant values of the passing probability and the relaxation time, and for values that depend on concentration in the manner assumed by Prigogine and Herman. It is hypothesized that this result reflects the well-known tendency toward substantial scatter in observational data of traffic flow at high concentrations.     

分析案例 强化本质 提高海运安全管理水平

文章利用数据统计图、表等方法,分析我国及国际上船舶水上交通事故特点及要因,掌握水上交通事故重点防范的对象,提出遏制水上交通事故在人、机、环、管理等方面的有效对策。     

铁路职工伤亡事故管理信息系统模型之研究

指出了建立全路职工伤亡事故管理信息系统的必要性。对事故信息进行统计分析的方法及统计指标、分析指标的选择。提出了安全评价和安全预测的研究思路。说明数据库和模型库设计与维护的方法。     

静音发电机组在野战车载系统中的应用技术研究

简要介绍了静音发电机组的外军应用情况及技术特点,提出了研制过程中涉及的关键技术及其方案。     

道路交通事故经济损失灰色预测模型

阐述了我国交通事故造成经济损失的状况,引入灰色预测模型,对利用此模型预测交通事故经济损失的可行性进行了分析。基于历史数据,对未来几年的事故经济损失状况进行预测,并对模型精度进行检验。     

The relationship among highway geometrics,traffic-related elements and motor-vehicle accident frequencies

This research provides a demonstration of a statistical model of accident frequency that can eventually be used as part of a proactive program to allocate safety-related highway improvement funds. Negative binomial regressions of annual accident frequency on sections of principal arterials in Washington State were estimated using data from two years (1992 and 1993). In all, 31306 observations were used in model estimation (annual accident frequencies on specific sections of highway). Our estimation results isolated the effects of various highway geometric and traffic characteristics on annual accident frequency. Subsequent elasticity computations identified the relative importance of the variables included in our specifications. The findings show that the negative binomial regression used in this paper is a powerful predictive tool and one that should be increasingly applied in future accident frequency studies.     

车头间距分布规律的研究

以我国混合车流作为高等级公路交通流的基本构成,分析了混合车流车型跟驶序列组合的概率;采用计算机模拟手段,得到了车头时距阈值与速度关系、不同跟车序列最小车头间距、车头间距与随机度关系和车头间距与流量关系;并通过随机度参数将微观和宏观参数整合为一体。     

Maritime accident risk estimation for sea lanes based on a dynamic Bayesian network

ABSTRACT

The safety of maritime transportation has become increasingly important with the development of international economics and trade. This paper introduces a dynamic Bayesian network (DBN) model to facilitate the estimation of the dynamic emergency risk in sea lanes. The DBN model is a novel model that can efficiently represent and infer complex stochastic knowledge. To construct this model, available data, which were collected from emergency investigation reports by the International Maritime Organization (IMO), are employed in conjunction with expert knowledge to develop and demonstrate a BN; an evidence theory approach is applied to calculate the prior probability with the help of historical data; the conditional probability is learned by the expectation maximization (EM) algorithm; and the transition probability is obtained by a Markov model. Finally, the Viterbi algorithm is adopted to estimate emergency risk. The emergencies that occurred in the Indian Ocean from 2009 to 2018 were used as a case study for risk estimation. Sensitivity analysis was conducted to identify significant influential factors. The results show that the sea lane risk in the Indian Ocean fluctuates within a small range, presenting an overall downward trend over time. These findings provide a reference for maritime stakeholders to make proper decisions.