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121.
钢轨断面的廓形参数对钢轨焊接后的平直度、焊后打磨、钢轨品质等影响重大。针对钢轨焊接前的轨端廓形检测,在激光传感器采集的廓形数据基础上,详细论述数据的处理方法和过程,主要包括数据的预处理、数据的融合、分段拟合、廓形的计算等,分析不同方法针对该研究目的的可行性、适应性以及准确性,最终选择移动平均法进行数据的预处理,采用矩形标准块和圆柱标准块标定进行数据融合,基于协方差矩阵的特征值选取分段点,最小二乘法进行分段拟合。试验数据表明,该方法对数据处理的效果良好,可以高效精确地检测出钢轨焊前断面的廓形尺寸。 相似文献
122.
应答器报文是实现CTCS-2级列控系统功能的关键数据。介绍了一种基于数据可视化方法分析验证应答器报文的软件——BTViewer的设计和实现,该软件为应答器报文的设计分析、现场维护提供了全新的手段和工具。 相似文献
123.
乘客信息显示系统移动宽带传输网建设与思考 总被引:1,自引:0,他引:1
移动宽带传输网实现了乘客信息显示系统(PIDS)地面设备与车载设备之间的双向信息交换,是PIDS系统的重要组成部分。研究广州地铁1—4号线PIDS移动宽带传输网建设方案,对车-地信息传输方式进行分析,讨论几种无线传输技术,并对网络冗余设计和抗干扰进行分析。 相似文献
124.
This study addresses the issue of eco-design for transportation in sustainable supply chain management (SSCM). Data envelopment analysis (DEA) is adopted and extended to construct a model for this application. This proposed model, together with the tractable algorithm developed in this research, can provide stakeholders with a Pareto Optimal transportation strategy. This derived transportation strategy can help stakeholders realize certain transportation goals with less resource consumption and pollution emission. The discussion presented leads to a heuristic Joint Transportation Policy and concludes with two useful suggestions for putting the strategy into practice. The proposed model was used in an empirical study of design sustainable transportation mechanism for one air-condition manufacturer in China to transport its products as well, the analysis further demonstrating the theoretical and practical value of this research. 相似文献
125.
文章提出运用网络云空间作为师生互动交流的通道,籍以再现经典"1对1"改图模式教学效果的教学改革路径,并运用云空间和数据挖掘技术进行设计图纸数据的积累和动态分析,有助于提升学生艺术设计能力的个性特质。 相似文献
126.
Traffic congestion has become a major challenge in recent years in many countries of the world. One way to alleviate congestion is to manage the traffic efficiently by applying intelligent transportation systems (ITS). One set of ITS technologies helps in diverting vehicles from congested parts of the network to alternate routes having less congestion. Congestion is often measured by traffic density, which is the number of vehicles per unit stretch of the roadway. Density, being a spatial characteristic, is difficult to measure in the field. Also, the general approach of estimating density from location-based measures may not capture the spatial variation in density. To capture the spatial variation better, density can be estimated using both location-based and spatial data sources using a data fusion approach. The present study uses a Kalman filter to fuse spatial and location-based data for the estimation of traffic density. Subsequently, the estimated data are utilized for predicting density to future time intervals using a time-series regression model. The models were estimated and validated using both field and simulated data. Both estimation and prediction models performed well, despite the challenges arising from heterogeneous traffic flow conditions prevalent in India. 相似文献
127.
从网络设备、路由规划、用户隔离、防攻击、信息加密、终端安全等方面对铁路信息网络面临的各种安全问题进行了探讨。针对这些问题,作者结合实际工作提出了相应的解决方案。 相似文献
128.
129.
底盘测功机工作原理及使用 总被引:1,自引:0,他引:1
底盘测功机以其方便、安全和溯源性好等优势在汽车开发及检测工作中得到广泛应用。利用数据采集卡实现驱动力和车速的测量,通过单片机与PC机通信可实现传感器信号的采样和数据传送。文章采用底盘测功机测量驱动轮输出功率来换算发动机功率,分析驱动轮输出功率不足的原因并得出底盘的技术状况。底盘测功机可用以模拟汽车在实际行驶时的阻力、测定汽车的使用性能、检测汽车的技术状况以及诊断汽车故障。 相似文献
130.
Alan J. Horowitz 《运输规划与技术》2013,36(1-2):139-153
Transportation network data structures must be designed to meet the requirements of the analyses being conducted and must be compatible with the selected graphical user interface. Increasing interest in geographic information systems (GIS) and intelligent transportation systems (ITS) have further burdened the network data structure. It is possible to implement object oriented programming (OOP) technology to satisfy these needs, without making the data structure excessively complicated. This paper shows how a well‐developed network data structure can incorporate major capabilities normally associated with stand‐alone GIS's. The design of a network data structure derives from both theoretical and practical considerations. A design of a network data structure, composed entirely of objects, is presented. Examples of its implementation, limitations, advantages, and possible extensions are drawn from experience with the General Network Editor (GNE). 相似文献