增压柴油机内冷油腔活塞结构分析及评价

以增压柴油机振荡内冷却油腔活塞非对称性结构为研究对象,构建了全活塞-活塞销-连杆小头的有限元接触模型,分析了活塞工作条件下的导热耦合关系。确定了当量换热边界条件;进行了在机械-热负荷联合作用下的结构应力及变形分析;为直观反映温度因素对活塞结构强度的影响,提出了对结构应力合理表述的应力-温度散点图评价方法;在此基础上对原有的活塞结构进行了改进。     

联图Fs ∨ Km,n的邻点可区别全色数

设G是简单图,k是正整数,f是V(G)∪E(G)到{1,2,…,k}的映射.对任意u∈V(G),记C(u)={f(u)}U{f(uv)|uv∈E(G),v∈V(G)}.如果f为G的正常全染色,且对任意uv∈E(G),有C(u)≠C(v).那么称f为G的k-邻点可区别全染色(简记为k-AVDTC).称xat(G)=min{k|图G存在k-AVDTC}为G的邻点可区别全色数.给出了联图Fs ∨ Km,n的邻点可区别全色数.     

高度图的邻点可区别的全染色界的一点注

A.C.Burris猜想:对于一个简单图G,它的邻点可区别的全色数aχt(G)≤Δ(G) 3其中Δ(G)表示G的最大度,本文证明了对Δ(G)=|V(G)|-1时,猜想为真.     

基于键图理论的汽车平顺性仿真分析

探讨键图理论用于汽车平顺性仿真分析的方法,将所建立的汽车四自由度振动键图模型与Matlab的Simulink仿真工具箱仿真方框图相连接,直接利用Simulink的可视化功能,实现汽车平顺性可视化仿真。键图模型和Simulink仿真工具箱的连接可使键图理论在汽车系统仿真分析研究中更为简便、快捷。     

关于多部图Kn(t)的{K4-e,S3}-强制分解

设n,t为正整数,以K_n(t)表示基于顶点集X=■X_i上的完全n部图。文章证明了(Kn(t),｛K4-e,S3｝)—强制分解存在当且仅当n≥3且(n,t)≠(3,2)。     

Evaluation of green wave policy in real-time railway traffic management

In order to face the expected growth of transport demand in the next years, several new traffic control policies have been proposed and analyzed both to generate timetables and to effectively manage the traffic in real-time. In this paper, a detailed optimization model is used to analyze one such policy, called green wave, which consists in letting trains wait at the stations to avoid speed profile modifications in open corridors. Such policy is expected to be especially effective when the corridors are the bottleneck of the network. However, there is a lack of quantitative studies on the real-time effects of using this policy. To this end, this work shows a comparison of the delays obtained when trains are allowed or not to change their speed profile in open corridors. An extensive computational study is described for two practical dispatching areas of the Dutch railway network.     

Accommodating user preferences in ad hoc shared ride trip planning using GIS

Ad hoc shared ride trip planning (SRTP) utilizes mobile devices, geo-sensors and wireless networks to match on-the-fly individual travel demand with transport supply. It represents one of many alternatives to single occupancy vehicle use. This paper outlines a SRTP approach via a two-phase algorithm based on user preferences in a time-dependent routing. Whereas current algorithms use minimization of travel time as the only optimization criterion in trip planning, in the framework presented here, the user can specify multiple trip preferences including travel time, walking time, number of transfers between cars and trip length. Various scenarios are simulated in the city of Tehran (Iran) to demonstrate how preference settings affect the routes of ad hoc shared journeys.     

基于图卷积网络的路网短时交通流预测研究

智能交通系统是缓解交通拥堵行之有效的手段,精准的交通流预测是其实现的关键所在. 本文考虑路网拓扑结构和交通流时空相关性,提出基于图卷积网络(Graph Convolution Network,GCN)的大规模城市路网短时交通流预测模型,具有较高的预测精度、预测效率和现实解释意义;采用真实大规模城市路网浮动车数据对GCN模型进行测试,结果表明,GCN模型相对于现有模型,在预测性能上有较大提升.     

基于多模式的公铁联合军事运输网络图模型研究

目前,我军多方式联合运输的主要手段是铁路和公路,在现实运用中军队重点关注运输方式转换的过程,以便合理地制定转运与保障方案。运用多模式网络建模和图论的相关理论与方法,根据部队联合输送任务需求和转运保障特点,采用铁路车站军事运输装卸载能力指数和军事运输道路通过能力指数评估方法,在地理地图的基础上,简化路网,建立公铁联合军事运输网络图模型,拟为军事联合运输路径优化研究提供方法。     

WD320动力稳定车计算机控制系统软件开发

介绍与大型养路机械０８－３２型岛固车配套使用的ＷＤ３２０动力稳定计算机控制系统的快速汉字显示，动态图形显示，以及适用于大批量逻辑表达式计算的软件开发技巧。