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251.
本着以学生为本的教育理念和立德树人的根本任务,汽车保险与理赔课程团队通过问卷、现场走访等形式对相关企业进行调研,结合调研情况和课程特点,基于岗位能力需求,对接职业标准,聚焦车险新政,从课程内容、教学模式和考核评价三方面进行课程创新设计,形成具有推广意义的专业课程设计思路,能有效提升教师课程设计的能力。教学团队利用改革后的课程在省级教学能力大赛中获得一等奖。  相似文献   
252.
为满足高职院校汽修类专业学生课程学习和大赛备赛需要,提高学生CAN总线故障检测诊断能力,进一步提升人才培养质量,文章在分析目前国内有关汽车CAN总线教学台架产品现状及问题的基础上,联合天津中汽恒泰教育科技有限公司深入研究迈腾B8轿车的总线控制技术,开发了迈腾B8轿车舒适CAN总线教学台架及配套实训教学软件。该实训台架将计算机信息技术引入课程教学,能够实现原理认知、信号解析和故障诊断等功能,助力理论教学与实践教学的有机统一;同时解决了实车中由于位置原因而导致检测不便的问题,减少了实操中对实车的损耗和破坏。  相似文献   
253.
文章认为英语专业口译课教学的重点应以技能训练为中心,并辅之以语言训练,探讨了培养学生综合素质的问题,同时介绍了几种常见的技巧:记忆技巧、笔记技巧、公众演说技巧等。  相似文献   
254.
文章分析传统与多媒体两种教育模式的内涵及功能特点,指出高等院校课堂教学中存在问题,探讨问题解决方法,强调教师应提高两种模式的科学认识。同时也指出实际教学中应根据教学内容、教学对象、教师水平合理将两种教学模式有机结合,有效提高课堂教学效果。  相似文献   
255.
文章基于1∶10的相似比制作拱顶带单条纵向裂缝且裂缝深度为原衬砌厚度1/3的隧道二次衬砌模型,采用弹簧模拟地层抗力,进行了分离式套拱加固衬砌(原衬砌与新增套拱之间增设防水板)的径向加载试验,得出了带裂缝衬砌经分离式套拱加固后的变形规律与破坏模式。结果表明,在松动荷载作用下,分离式套拱加固结构的受力过程分为"初期加载—预制裂缝径向贯通、预制裂缝径向贯通—套拱拱顶裂缝径向贯通、套拱拱顶裂缝径向贯通—试件破坏"三阶段,破坏荷载由原衬砌拱腰截面控制,关键部位破坏顺序为拱顶开裂—拱腰断裂—拱顶破坏,整体破坏性质为脆性破坏。  相似文献   
256.
大跨径梁式桥的主要病害   总被引:28,自引:8,他引:28  
论述了预应力混凝土大跨径梁式桥的两种主要病害,一是跨中下挠,二是梁体开裂。分析了跨中下挠、垂直裂缝、斜裂缝、纵向裂缝的原因,并叙述了预防对策。这些对策主要是:梁有足够的正截面和斜截面强度;设计中要控制恒载挠度(包括徐变挠度)在一个较小值;在梁纵向两悬臂端施加水平力对顶后合龙;三维分析箱梁主拉应力并布置预应力束;预留体外备用钢束;混凝土加载龄期不小于7天;竖向预应力应两次张拉以保证有效预应力。  相似文献   
257.
Couplers of motor units connect the wagons mechanically, electrically and pneumatically. Nowadays they are also designed to meet crash requirements. Since the traction and braking forces are distributed along the motor unit, coupler forces occuring during operation are considered to be low. In most cases, this is actually true. However, towing away a defect motor unit by another motor unit can lead to high forces due to longitudinal vibrations, which may ultimately lead to a failure of the coupler or superstructure. Investigations on the behaviour of motor units operating in an European city have been carried out for about 3 years [Kühnel, A., Hecht, M., Udriste-Breazu, I., Geike, T. and Böhme, C., Kräfte beim Bergen liegengebliebener U-Bahnen—ein unterschätztes Risiko. ZEVrail-Glasers Annalen, Tagungsband SFT Graz, 2004, pp. 128–136; Udriste-Breazu, I., Böhme, C., Kühnel, A. and Hecht, M., Behaviour of Motor Unit Couplers in Towing Case. 4th International Symposium on Passive Safety of Rail Vehicles, Okt. 2003, Berlin, Germany, homepage www.ifv-bahntechnik.de.]. The research has always been focussed on the certain parameters and conditions of the motor units under study. Little effort has been made to theoretically study the problem on a general basis. The aim of this paper is to close this gap.  相似文献   
258.
It has been suggested that commuting behaviours become habitual and that changes to commute mode are more likely at the time of major life events. However, evidence to support this has so far been limited to analyses of small-scale samples. To address this evidence gap, we use two waves of panel data from the UK Household Longitudinal Study (2009/10 and 2010/11) to identify and explain the prevalence of individual change in commute mode from year to year amongst a representative sample of the English working population (n = 15,200). One third of those that cycle or get the bus to work, and one quarter of those that walk to work, are shown to change commuting mode by the following year. Car commuting is more stable, with only one in ten car commuters changing mode by the following year. Commute mode changes are found to be primarily driven by alterations to the distance to work which occur in association with changing job or moving home. Switching to non-car commuting becomes much more likely (9.2 times) as the distance to work drops below three miles. High quality public transport links to employment centres are shown to encourage switches away from car commuting and mixed land uses are shown to encourage switches to active commuting (walking and cycling). Switches away from car commuting are found to be more likely (1.3 times) for those with a pro-environmental attitude. The attitude orientation is shown to precede the behaviour change, demonstrating evidence of ‘cause and effect’. Overall, the study shows that changes in commuting behaviour are strongly influenced by life events, spatial context and environmental attitude.  相似文献   
259.
A series of collapse analyses is performed applying nonlinear FEM on stiffened panels subjected to longitudinal thrust. MSC.Marc is used. Numbers, types and sizes of stiffeners are varied and so slenderness ratio as well as aspect ratio of local panels partitioned by stiffeners keeping the spacing between adjacent longitudinal stiffeners the same. Initial deflection of a thin-horse mode is imposed on local panels and that of flexural buckling and tripping modes on stiffeners to represent actual initial deflection in stiffened panels in ship structures. On the basis of the calculated results, buckling/plastic collapse behaviour of stiffened panels under longitudinal thrust is investigated. The calculated ultimate strength are compared with those obtained by applying several existing methods such as CSR for bulk carriers and PULS. Simple formulas for stiffened panels, of which collapse is dominated fundamentally by the collapse of local panels between longitudinal stiffeners, are also examined if they accurately estimate the ultimate strength. Through comparison of the estimated results with the FEM results, it has been concluded that PULS and modified FYH formulas fundamentally give good estimation of the ultimate strength of stiffened panels under longitudinal thrust.  相似文献   
260.
An approach is presented to assess the reliability of ship hulls made of composite materials under sagging moments. Buckling, first-ply failure, and ultimate collapse are regarded as the three possible failure modes of ship hulls of composite materials under sagging moments. Reliability estimates were carried out by a combination of the first-order second-moment method and the response surface methodology. A ship hull of composite materials under sagging moments was evaluated and the results showed that the effects on reliability estimates of the model uncertainty in the longitudinal strength of the ship hull, the model uncertainty of the sagging moments, and the sagging moments were significant, whereas the influences of the stochastic characteristics of material elastic moduli were relatively unimportant.  相似文献   
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