AMT自动换档变速器在城市客车上的应用

介绍一种正在兴起的变速技术———AMT(Automated Mechanical Transmission)自动换档变速器,阐述其发展过程、工作原理、性能特点及其在城市客车上的应用前景。     

三维方位关系的定性描述与定性推理

结合定性推理、空间推理与人工智能产生的定性空间推理,已成为人工智能的1个研究热点,是空间关系的重要组成部分,为空间方位关系空间分析、辅助决策等提供了基础。因此,空间方位关系的形式化描述与定性推理非常重要。本文用单纯形数据模型描述三维空间实体,通过研究单纯形间的方向关系研究空间实体间的方向关系。提出采用三元组描述了两空间对象间的三维方位关系,并对该描述方法的定性推理作了详细研究。三维方位关系分为单方位关系与多方位关系,重点研究了单方位关系定性推理,在此基础上分析了多方位关系定性推理与单方位关系定性推理方法的联系,将多方位关系定性推理转化为对多个单方位关系定性的推理。     

Development of a knowledge-based hybrid failure diagnosis system for urban transit

Urban transit is a complex system that contains both electrical and mechanical entities; therefore, it is necessary to construct a maintenance system for ensuring safety during high-speed driving. Expert systems are computer programs that use numerical or non-numerical domain-specific knowledge to solve problems. This research aims to develop an expert system that diagnoses the causes of failures quickly and displays measures to correct them. For the development of this expert system, the standardization of a failure code classification and the creation of a Bill of Materials (BOM) were first performed. Through the analysis of both failure history and maintenance manuals, a knowledge base has been constructed. Also, for retrieving the procedure of failure diagnosis and repair linking with the knowledge base, we have built a Rule-Based Reasoning (RRB) engine with a pattern matching technique and a Case-Based Reasoning (CBR) engine with a similar search method. Finally, this system has been developed as web based in order to maximize accessibility.     

CASE STORAGE BASED ON RELATIONAL DATABASE

IntroductionCase- Based Reasoning ( CBR) ,as a relativelynew methodology,has attracted wide concern ofAI researchers since1 980 's.The number of suc-cessful applications of CBR is growing rapidly,especially in the fields of architecture and indus-try,e.g. ARCHI- II[1] for the architecture designof courthouse and MIDAS[2 ] for the conceptualdesign of aircraft.The currently prevailing CBD systems mostlytreat cases as instances of some predeterminedand static case template.Such an appro…     

Cost overruns in transportation infrastructure projects: Sowing the seeds for a probabilistic theory of causation

Understanding the cause of cost overruns in transportation infrastructure projects has been a topic that has received considerable attention from academics and the popular press. Despite studies providing the essential building blocks and frameworks for cost overrun mitigation and containment, the problem still remains a pervasive issue for Governments worldwide. The interdependency that exists between ‘causes’ that lead to cost overruns materialising have largely been ignored when considering the likelihood and impact of their occurrence. The vast majority of the cost overrun literature has tended to adopt a deterministic approach in examining the occurrence of the phenomenon; in this paper a shift towards the adoption of pluralistic probabilistic approach to cost overrun causation is proposed. The establishment of probabilistic theory incorporates the ability to consider the interdependencies of causes so to provide Governments with a holistic understanding of the uncertainties and risks that may derail the delivery and increase the cost of transportation infrastructure projects. This will further assist in the design of effective mitigation and containment strategies that will ensure future transportation infrastructure projects meet their expected costs as well as the need of taxpayers.     

基于主成分分析的军用软件成本类比估算

论文探讨基于案例库的军用软件成本类比估算法。首先采用主成分分析抽取最具代表的软件度量组合,以此建立综合评估模型,以软件综合评估值为软件相似度度量,分析相似度与成本之间的相关关系,进而估算当前软件成本。案例的成功应用证明了方法的可行性和有效性。     

自动化集装箱码头智能闸口布置

在总结国外自动化集装箱码头闸口布置经验的基础上,提出自动化码头新型多级闸口布置形式,以提高进港集卡通过能力及闸口运作效率。多级闸口在洋山四期工程中被采用,其优越性得以体现,该方案可行性得到检验。     

基于自适应神经模糊推理系统的平行泊车路径规划

针对常见的平行泊车场景,提出一种基于自适应神经模糊推理系统的平行泊车路径规划方法.以基于优化算法的泊车路径规划方法得出的泊车路径作为训练样本,利用Python脚本语言建立以自适应遗传算法和拟牛顿法为内核的自动化训练框架,使自动训练后的自适应神经模糊推理系统既可继承基于优化算法的泊车路径规划方法适用范围更广的优势,又有效...     

考虑多车影响的分子动力学智能网联跟驰模型

为研究含智能网联汽车(Connected and Automated Vehicle, CAV)和人工驾驶汽车(Regular Vehicle, RV)混行交通流下CAV跟驰行为的控制问题,考虑前后多车的速度、车头间距、速度差、加速差等参数,采用分子动力学定量表达不同周边车辆对主体车的影响,得到可用于描述CAV在混行交通流中的跟驰过程。稳定性分析结果表明,与全速度差模型相比,本文提出的考虑前后多车信息的CAV跟驰模型有利于提高交通流的稳定性。数值仿真与模型验证结果表明,与PATH实验室的CACC(Cooperative Adaptive Cruise Control)模型相比,本文建立的CAV跟驰模型平均速度最大误差减小了0.19 m·s^-1,平均误差减小26.79%,拟合精度提高了0.91%。同时,在CAV和RV组成的混行交通流中,随着CAV比例的逐渐增加,车队的平均速度和交通流量逐渐增加。迟滞回环曲线表明,与全速度差(Full Velocity Difference, FVD)模型相比,本文提出的CAV模型控制下的交通流稳定性更强。该模型可用于同质流或CAV与...     

智能网联车环境下交叉口车流轨迹优化模型

在智能网联环境下,车辆可通过相互穿插和协作通过交叉口,无需信号灯控制.为保证车辆安全高效运行,建立车辆到达时序和速度协同优化的交叉口车流轨迹优化模型.提出车辆到达时序优化模型和车辆速度优化模型,建立车辆到达时刻与速度的函数关系;在此基础上,模型以所有车辆在控制区域的行程时间与油耗加权最小为目标,车辆路径、到达时刻和速度...