基于车次径路约束下的客运径路生成算法优化

针对目前客票径路计算中径路信息与实际旅客出行径路之间存在的差异性,从分析径路生成的计算模型出发,结合铁路通票业务背景,提出一种车次约束机制下的径路生成计算方法。算法以选择性集中存储为径路存取方式,实现径路公共信息的全路共享与车站特殊径路的分布式存取,有效压缩径路信息存储空间,提高径路选择效率;以车站-车次邻接表为基本数据结构,将铁路路网图改进为列车约束下的列车可达图,保证车站生成个性化径路的合理性和有效性;算法摒弃原有径路计算只计算本站至全路各个结算站间最短K路径的方法,分车站特殊径路计算和公共径路计算两步实现径路的计算,从根本上保证径路计算的有效性,解决通票径路与列车走行径路不符问题,实现了对现有径路生成算法的优化。     

长江航路的改革与发展

航路改革是长江航运史上的一次革命,它规范了船舶航行秩序,大大降低了交通事故发生率,提高了通航效率。本文从航路改革的意义,作法,收益入手,重点对航路改革的发展进行了探讨,具有一定的实践指导意义。     

基于马尔可夫过程的搜索力最优化模型研究

在引出马尔可夫搜索模型的基础上，探讨了一种有效的目标搜索方法，达到了优化搜索过程，提高搜索效率。应用最优搜索理论，导出了待搜目标服从均匀分布，正态分布时搜索力的最优配置预测分析，给出搜索力分配的新数学模型及数学规划解析。上述理论和方法为搜索力如何实施最优化搜索提供了一定的理论依据。     

遵守船舶报告制度 完善管理体系

简要介绍了中国船舶报告制度的概况,阐述了船舶加入该系统对履行国际公约,组织搜寻救助行动,维护人命、财产安全,保护国家、公司利益的重要性。提醒广大航海员在航行中应严格执行船舶报告制度,确保航行安全,同时避免违反规定程序报告而产生不必要的航海失误。     

竞争情报采集系统研究

在竞争情报系统中,情报采集是影响信息质量的重要环节,情报源整合策略、采集规则和采集策略是情报采集中的重要工作。从企业竞争情报系统应具备的特性和应用价值角度分析情报采集系统应具有的功能和总体架构,探索基于搜索引擎技术的情报采集系统开发方法,进而对关键部分予以实现。     

油罐底板渗漏的修补

某油罐底板发生了渗漏,采用AE声发射技术在油罐在用状态下检测出底板渗漏点的大致位置后,倒空油罐,对油罐内部管壁和底板进行热水循环清洗。用N2置换内部的油气,用轴流风机强制通风,检测罐内气体符合呼吸和防爆要求后,从人孔进入罐内。通过渗透检测和真空箱检测的方法精确找出缺陷位置,采用充N2隔离油气、浇水降温、钻孔等一系列措施挖除缺陷,更换底板下缺陷附件的含油沥青砂层。最后,在缺陷所在位置上焊接补丁钢板,成功地进行了易燃易爆油罐底板渗漏的修补。     

Modelling route choice behaviour in a tolled road network with a time surplus maximisation bi-objective user equilibrium model

In this paper, we propose a novel approach to model route choice behaviour in a tolled road network with a bi-objective approach, assuming that all users have two objectives: (1) minimise travel time; and (2) minimise toll cost. We assume further that users have different preferences in the sense that for any given path with a specific toll, there is a limit on the time that an individual would be willing to spend. Different users can have different preferences represented by this indifference curve between toll and time. Time surplus is defined as the maximum time minus the actual time. Given a set of paths, the one with the highest (or least negative) time surplus will be the preferred path for the individual. This will result in a bi-objective equilibrium solution satisfying the time surplus maximisation bi-objective user equilibrium (TSmaxBUE) condition. That is, for each O–D pair, all individuals are travelling on the path with the highest time surplus value among all the efficient paths between this O–D pair.We show that the TSmaxBUE condition is a proper generalisation of user equilibrium with generalised cost function, and that it is equivalent to bi-objective user equilibrium. We also present a multi-user class version of the TSmaxBUE condition and demonstrate our concepts with illustrative examples.     

A systematic review of route optimisation and pre-emption methods for emergency vehicles

ABSTRACT

Reducing the travel time of emergency vehicles (EVs) is an effective way to improve critical services such as ambulance, fire, and police. Route optimisation and pre-emption are powerful techniques used to reduce EV travel time. This paper presents a systematic literature review of optimisation and pre-emption techniques for routing EVs. A detailed classification of existing techniques is presented along with critical analysis and discussion. The study observes the limitations of existing routing systems and lack of real-world applications of the proposed pre-emption systems, leading to several interesting and important knowledge and implementation gaps that require further investigation. These gaps include optimisations using real-time dynamic traffic data, considering time to travel as a critical parameter within dynamic route planning algorithms, considering advanced algorithms, assessing and minimising the effects of EV routing on other traffic, and addressing safety concerns in traffic networks containing multiple EVs at the same time.     

基于OPN的舰载对空搜索雷达作战效能仿真分析

舰载对空搜索雷达的作战效能评估是电子战领域的一个研究热点,它的评估方法得到了广泛的研究.针对通常的模型不能同时描述舰载对空搜索雷达作战系统的静态结构和动态过程,采用对象Petri网建立了舰载对空搜索雷达作战系统的模型.首先在对舰载对空搜索雷达作战系统分析的基础上,设计了系统对象类,并运用OPDL语言对各个对象类和舰载对空搜索雷达作战过程进行了描述;然后选取了效能评估指标;最后利用所建立的OPN模型进行了仿真,通过仿真运行对不同对抗环境下舰载对空搜索雷达的效能进行了分析,仿真结果与实际相符合.