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排序方式: 共有1733条查询结果,搜索用时 15 毫秒
151.
LUO Yao-hua YE Xiu-fen YE Gui-yun LI Fu-yi PENG Xia-fuAutomation College Harbin Engineering University Harbin China 《船舶与海洋工程学报》2002,1(1):47-51
This paper introduces the composition, control method and testing results of the integrated control system for the firsttidal flow electricity generating (TFEG) ship of China. The control method, control algorithm and the specific circuits for thehydraulies system are also introduced. Our research works are emphasized on the control algorithm of stabilizing frequency andsome special problems of the controller.The related protection measures for hydraulic system and TFEG system have been tak- 相似文献
152.
分析了碾压混凝土的稠度特性,研究了改进维勃仪面荷载与压路机线压力的关系,指出了改进维勃仪的不足之处,提出了测量碾压混凝土稠度的新方法。 相似文献
153.
介绍一种列车接近防护系统的设计,详细介绍系统的结构与组成、系统参数以及软硬件的实现方法。 相似文献
154.
155.
铁路加筋土挡墙计算机辅助绘图技术 总被引:1,自引:0,他引:1
介绍铁路加筋土挡墙计算机辅助设计系统的总体实现思想 ,并对在AutoCAD2 0 0 0 /2 0 0 2平台上运用VisualLisp语言 ,研制开发的铁路加筋土挡墙计算机辅助绘图系统的具体实现过程进行论述。简要地对软件应用进行说明 ,给出执行结果。 相似文献
156.
自动售检票(AFC)系统作为地铁运营体系的核心部分,其信息的安全性需要得到充分保证.深圳地铁为了提升AFC系统的安全性,建立了信息安全管理体系.结合该体系建立过程,对风险评估的流程和重点进行了探讨.风险评估是在对AFC系统的资产、威胁和脆弱性进行详细的识别和估值后,再计算风险值,得出了系统中一系列存在风险的业务范围和较全面的安全需求. 相似文献
157.
罗利平 《城市轨道交通研究》2008,11(1):58-61
随着显示墙技术的发展,采用数字光处理(DLP)大屏幕投影显示技术已经是大势所趋.通过对大屏幕投影显示墙系统几个重要组成部分如显示技术、屏幕材质、屏幕尺寸等的探讨,结合武汉轨道交通的实践,提出:应用于监控系统的大屏幕投影显示墙,配置应采用DLP投影显示技术;应选用不变形、不反光、视角好、发光强度高的屏幕;屏幕尺寸可根据项目特点及人体视觉学等进行处理. 相似文献
158.
This paper establishes the simulation model of a city bus on the basis of the EQ6110 bus prototype and its experimental data.
According to the actual urban driving cycle, the fuel economy and the traction performance of the EQ6110 city bus have been
simulated, and factors such as the driving cycle, the loss of power to engine accessories, the gear-shifting strategy, the
fuel shut-off strategy of the engine, etc., which influence on the bus’s fuel economy, are also quantitatively analyzed. Some
conclusions are drawn as follows: (1) driving cycles have a great influence on the fuel economy of a city bus; (2) under the
typical urban driving cycle of the public bus in China, the engine fuel shut-off strategy can save about 1 to 1.5 percent
of the fuel consumption; and (3) the optimized gear-shifting rules can save 6.7 percent of the fuel consumption. Experimental
results verify that the fuel economy for the EQ6110 public bus is improved by 7.2 pecent over the actual Wuhan urban driving
cycle of the current public bus in China. 相似文献
159.
基于Zigbee和GPRS的无线公交考勤管理系统 总被引:1,自引:0,他引:1
目前各城市公交公司主要采用人工打卡方式作为公交车考勤的主要手段,操作起来既不方便又费时。本文提出一种基于Zigbee技术和GPRS的无线智能公交考勤系统。该系统通过Zigbee无线传输技术实现车载终端与考勤打卡机通信,由打卡机记录下公交车的车号和时间,再通过GPRS技术传输到管理中心,实现对运行中的公交车进行监控和定位,具有方便省时,简单可靠,成本低等优点。 相似文献
160.
Chunsheng Li Shihui Luo Colin Cole Maksym Spiryagin 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2018,56(10):1604-1621
An on-board health monitoring system is proposed for heavy haul wagons in this paper including a signal-based fault detection and isolation (FDI) method and an on-line fault diagnose strategy. Such a system, to be feasible on freight wagons, must be sufficiently cheap and robust, hence the design assumes the constraint of using only two accelerometers mounted on the front left and right rear part of each carbody in a heavy haul train. This paper focuses on the detection of bolster spring fault conditions. The problem is made more complex by the modes of failure which might be expected in bolster spring nests. Types of spring failure are firstly identified and discussed covering situations of broken (shortening springs) and softening (individual spring loss from a nest or cross-section loss through corrosion). The effects of these faults and their detectability were investigated using simulations on straight and curved track and using a fully detailed model of a typical 40?t axle-load heavy haul wagon. The simulation results were then examined and compared using cross-correlation analysis and an FDI system was proposed. The FDI system introduced five possible fault indicators. Initial results indicated that it was possible to detect changes in bolster stiffness of ±25%. An on-line fault diagnoses strategy is proposed for bolster spring faults which only requires data from wagon monitoring during travel around sharp curves to detect and the occurrence of confirm faults. The functionality envisaged needs only a ‘once per trip’ monitoring site, such as a sharper curve, and is aimed at condition monitoring rather than the provision of alarms or comprehensive monitoring of all events. 相似文献