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91.
This paper aims at demonstrating the usefulness of integrating virtual 3D models in vehicle localization systems. Usually, vehicle localization algorithms are based on multi-sensor data fusion. Global Navigation Satellite Systems GNSS, as Global Positioning System GPS, are used to provide measurements of the geographic location. Nevertheless, GNSS solutions suffer from signal attenuation and masking, multipath phenomena and lack of visibility, especially in urban areas. That leads to degradation or even a total loss of the positioning information and then unsatisfactory performances. Dead-reckoning and inertial sensors are then often added to back up GPS in case of inaccurate or unavailable measurements or if high frequency location estimation is required. However, the dead-reckoning localization may drift in the long term due to error accumulation. To back up GPS and compensate the drift of the dead reckoning sensors based localization, two approaches integrating a virtual 3D model are proposed in registered with respect to the scene perceived by an on-board sensor. From the real/virtual scenes matching, the transformation (rotation and translation) between the real sensor and the virtual sensor (whose position and orientation are known) can be computed. These two approaches lead to determine the pose of the real sensor embedded on the vehicle. In the first approach, the considered perception sensor is a camera and in the second approach, it is a laser scanner. The first approach is based on image matching between the virtual image extracted from the 3D city model and the real image acquired by the camera. The two major parts are: 1. Detection and matching of feature points in real and virtual images (three features points are compared: Harris corner detector, SIFT and SURF). 2. Pose computation using POSIT algorithm. The second approach is based on the on–board horizontal laser scanner that provides a set of distances between it and the environment. This set of distances is matched with depth information (virtual laser scan data), provided by the virtual 3D city model. The pose estimation provided by these two approaches can be integrated in data fusion formalism. In this paper the result of the first approach is integrated in IMM UKF data fusion formalism. Experimental results obtained using real data illustrate the feasibility and the performances of the proposed approaches.  相似文献   
92.
The number of variables involved in the monitoring of an ecosystem can be high and often one of the first stages in the analysis is to reduce the number of variables. We describe a method developed for geological purposes, using the information theory, that enables selection of the most relevant variables. This technique also allows the examination of the asymmetrical relationships between variables. Applied to a set of physical and biological variables (plankton assemblages in four areas of the North Sea), the method shows that biological variables are more informative than physical variables although the controlling factors are mainly physical (sea surface temperature in winter and spring). Among biological variables, diversity measures and warm-water species assemblages are informative for the state of the North Sea pelagic ecosystems while among physical variables sea surface temperature in late winter and early spring are highly informative. Although often used in bioclimatology, the utilisation of the North Atlantic Oscillation (NAO) index does not seem to provide a lot of information. The method reveals that only the extreme states of this index has an influence on North Sea pelagic ecosystems. The substantial and persistent changes that were detected in the dynamic regime of the North Sea ecosystems and called regime shift are detected by the method and corresponds to the timing of other shifts described in the literature for some European Systems such as the Baltic and the Mediterranean Sea when both physical and biological variables are considered.  相似文献   
93.
对舰载信息系统数据融合攻击分析   总被引:1,自引:0,他引:1  
针对对舰载信息系统的攻击,分析了系统的易损性,提出对数据融合系统的攻击类型,给出了攻击矩阵,并对攻击效果作了简单定性分析。  相似文献   
94.
一种面向海事分支机构的船舶安全管理信息系统的设计   总被引:1,自引:0,他引:1  
针对直属海事局分支机构船舶安全管理业务的需求,提出一种船舶安全管理信息系统的设计思路。该系统将电子海图平台、船舶交通动态数据和船舶安全管理信息集成,以实现船舶安全管理数字化、信息化、网络化。从系统技术实现角度,对信息管理系统作出详细的设计与分析。  相似文献   
95.
国内信息     
交通部认真做好2008年春节运输工作;交通部开展暴风雷应对准备工作检查确保水上交通安全;交通部公布全国主要港口引航员登轮点。  相似文献   
96.
从知识融合的物理层次角度,对发动机智能化故障诊断系统的知识融合技术进行了探讨,通过对知识融合内容各节点以及接口的研究,证明了知识融合具有互补性、实时性、低成本性和再学习等优点。该项研究成果为实现发动机智能化故障诊断提供了一条新的途径。  相似文献   
97.
周申培  严新平 《ITS通讯》2005,7(3):43-45
交通流量预测是智能运输系统的一个重要组成内容,但传统的数学方法一直未能取得令人满意的预测效果。信息融合技术是最近十多年来新兴的技术。它通过合理协调多源数据,充分综合有用信息,在较短的时间内,以较小的代价获得对未来交通流量的预测。实验证明,借助信息融合理论建立的聚类分析模型和神经网络模型对未来交通流量的预测比较准确,有实际意义。  相似文献   
98.
讨论了视觉传感器和2维、3维成像声纳的数据融合方法,利用传感器间的外标定方法,把成像声纳的特征元素转换到相机坐标系中,再利用计算机视觉领域的structure from motion 方法进行求解.仿真实验表明,随着时间的推移,误差变得越来越小;经多传感器融合后,实验误差比融合前要小,结果精度比单个传感器高.  相似文献   
99.
以SuperMap地理信息系统为基础平台,实现公路养护与施工数据的共享,建立一套管理信息系统,能完成图形、属性、影像、文本高度集成的一体化数据库可视化统一管理,提高公路养护的效率,并能为决策提供支持。  相似文献   
100.
结合近年来基建工程通信、信息系统建设情况,探讨通信、信息系统设计原则。  相似文献   
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