新型折流板装置运动机构优化研究

随着燃机动力的发展,现有活动式折流板装置在动力试验尾气折流中已无法满足未来的使用要求。针对现有折流板装置的不足,采用将折流板气流冲刷面与车辆通过面分离的方法,提出一种新型折流板方案,并对新型方案的车辆通过面和运动执行机构进行优化,以降低装置的重量及对动力源的需求。最后对新型装置的性能参数进行分析,为后续设计提供参考。     

CFRP-圆钢管混凝土偏压柱承载力回归分析

根据16根CFRP-圆钢管混凝土偏压柱承载力的试验研究,对CFRP-圆钢管混凝土偏压柱的受力性能及工作机理进行简要分析;并且以钢管混凝土理论计算及CFRP-圆钢管混凝土轴压短柱理论计算为基础,回归出CFRP-圆钢管混凝土偏心受压构件的简化计算式;应用简化计算式的计算结果与实验结果吻合良好且偏于安全,满足工程需要。     

Alternative approaches to spatial modelling

In discussion of the modelling methods that can be used to assess the impacts of transport change on regional and local economies, “land-use/transport interaction (LUTI) models” are often referred to as if all such models were examples of a single, homogeneous commodity. The first and major purpose of this paper is to correct this impression by comparing and contrasting some key features of the main models or modelling packages in the LUTI tradition, particularly those which are generally recognized as constituting the current “state-of-the-art”, or at least the “state of practice”. One particular point within the comparison will be the differing use which is made (or not made) of spatial input-output models in the different approaches.The second purpose of the paper is (more briefly) to compare LUTI modelling with alternative approaches and in particular with spatial computable general equilibrium (SGCE) modelling. One of the common features to emerge from the preceding comparison is that LUTI modelling has been mainly concerned with predicting the location of fixed totals of jobs and of households under different transport scenarios. This is a general feature, even though in some cases these totals are directly fixed by the user whilst in other cases they are the results of long chains of calculations that are insensitive to transport scenarios; in a few cases, the total levels of economic activity are variable according to accessibility-related variables. In contrast, the use of SCGE modelling in testing the impact of transport proposals is very much concerned with the consequences for the total size of the economy in question, usually with a less detailed concern for the spatial distribution of impacts. This comparison leads to a discussion of whether LUTI modelling and SCGE modelling are mutually exclusive or whether some form of synthesis or integration between the two may be theoretically appropriate and/or practically desirable. The requirements of project appraisal - i.e., the assessment of benefits - are also considered.     

型号研制项目管理的质量监督工作浅析

介绍了项目管理中质量控制思路,指出应在项目管理中贯彻全系统、全寿命的质量观,并结合军代表质量监督工作的实践,对国防军工企业型号项目管理中的质量控制工作从立项论证、工程研制、生产过程和使用维修几个阶段进行了阐述.     

Green-Naghdi theory, part A: Green-Naghdi (GN) equations for shallow water waves

In this work,Green-Naghdi (GN) equations with general weight functions were derived in a simple way. A wave-absorbing beach was also considered in the general GN equations. A numerical solution for a level higher than 4 was not feasible in the past with the original GN equations. The GN equations for shallow water waves were simplified here, which make the application of high level (higher than 4) equations feasible. The linear dispersion relationships of the first seven levels were presented. The accuracy of dispersion relationships increased as the level increased. Level 7 GN equations are capable of simulating waves out to wave number times depth . Numerical simulation of nonlinear water waves was performed by use of Level 5 and 7 GN equations, which will be presented in the next paper.     

Social influences on household location, mobility and activity choice in integrated micro-simulation models

Agent-based approaches to simulating long-term location and mobility decisions and short-term activity and travel decisions of households and individuals are receiving increasing attention in land-use and transportation interaction (LUTI) models to predict land-use changes and travel behaviour in mutual interaction. Social interactions between households and between individuals potentially have an influence on a wide range of the long-term and short-term choices involved in these systems. In this paper we identify the areas in which social interactions play a role and address the question how these influences can be modelled in the context of agent-based LUTI models. We distinguish impacts on activity participation (joint activity participation, support-and-help activities) and impacts on decision making (information exchange, social adaptation of preferences and aspirations) as the two main areas of social influence. A prototype of a LUTI model is proposed that accounts for impacts of the social network on longer-term mobility decision making through information exchange and social adaptation of preferences and aspirations. The model is demonstrated in a numerical simulation.     

基于耐久性的隧道结构设计的几个问题

隧道结构应在设计使用年限内满足结构的安全性、适用性和耐久性要求,目前隧道结构的耐久性设计方法还不够完善。隧道结构的耐久性不能仅仅按照提高材料的质量和加大结构厚度等构造要求进行设计,还应该采用多道设防的设计理念,结合结构安全性设计,综合考虑隧道结构在环境作用下的耐久性。文章结合隧道结构的耐久性,对复合式衬砌隧道结构设计中的几个问题进行了分析与探讨,并提出了解决方案。     

混合动力客车再生制动}姑阢娟金台结构方案

文章介绍了基于某系列混合动力城市客车而设计的再生制动模拟试验台的组成与原理,并在分析该模拟试验台各模拟系统及其应该满足的要求的基础上,对基于某混合动力城市客车总成结构而设计的2种再生制动模拟试验台的结构方案进行了比较分析,选出了一种具有安全性和稳定性的再生制动模拟试验台结构,这种结构还具有便捷的扩展性以及多功能性     

平原区双车道公路交通条件与交通安全的关系研究

以平原区双车道公路交通事故资料为基础,分析了道路平曲线和纵断面线形及交叉口等因素与交通事故的关系,将分析结论和国外研究结果相对比,得出我国平原区双车道公路交通条件与交通安全的关系,并建立交通安全性预测模型,对提升我国双车道公路安全性具有重要的意义。