全文获取类型
收费全文 | 2435篇 |
免费 | 317篇 |
国内免费 | 233篇 |
专业分类
电工技术 | 145篇 |
综合类 | 474篇 |
化学工业 | 28篇 |
金属工艺 | 13篇 |
机械仪表 | 244篇 |
建筑科学 | 333篇 |
矿业工程 | 37篇 |
能源动力 | 31篇 |
轻工业 | 15篇 |
水利工程 | 9篇 |
石油天然气 | 5篇 |
武器工业 | 106篇 |
无线电 | 218篇 |
一般工业技术 | 126篇 |
冶金工业 | 29篇 |
原子能技术 | 5篇 |
自动化技术 | 1167篇 |
出版年
2024年 | 23篇 |
2023年 | 87篇 |
2022年 | 109篇 |
2021年 | 116篇 |
2020年 | 127篇 |
2019年 | 99篇 |
2018年 | 74篇 |
2017年 | 78篇 |
2016年 | 89篇 |
2015年 | 121篇 |
2014年 | 209篇 |
2013年 | 162篇 |
2012年 | 211篇 |
2011年 | 205篇 |
2010年 | 160篇 |
2009年 | 116篇 |
2008年 | 134篇 |
2007年 | 164篇 |
2006年 | 138篇 |
2005年 | 112篇 |
2004年 | 79篇 |
2003年 | 74篇 |
2002年 | 58篇 |
2001年 | 50篇 |
2000年 | 39篇 |
1999年 | 25篇 |
1998年 | 34篇 |
1997年 | 20篇 |
1996年 | 22篇 |
1995年 | 16篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 4篇 |
1991年 | 6篇 |
1990年 | 2篇 |
1989年 | 6篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1979年 | 1篇 |
1959年 | 1篇 |
排序方式: 共有2985条查询结果,搜索用时 15 毫秒
1.
Yingcai Bi Menglu Lan Jiaxin Li Shupeng Lai Ben M. Chen 《Asian journal of control》2019,21(4):1732-1744
Micro Aerial Vehicles (MAVs) have great potentials to be applied for indoor search and rescue missions. In this paper, we propose a modular lightweight design of an autonomous MAV with integrated hardware and software. The MAV is equipped with the 2D laser scanner, camera, mission computer and flight controller, running all the computation onboard in real time. The onboard perception system includes a laser‐based SLAM module and a custom‐designed visual detection module. A dual Kalman filter design provides robust state estimation by multiple sensor fusion. Specifically, the fusion module provides robust altitude measurement in the circumstance of surface changing. In addition, indoor‐outdoor transition is explicitly handled by the fusion module. In order to efficiently navigate through obstacles and adapt to multiple tasks, a task tree‐based mission planning method is seamlessly integrated with path planning and control modules. The MAV is capable of searching and rescuing victims from unknown indoor environments effectively. It was validated by our award‐winning performance at the 2017 International Micro Air Vehicle Competition (IMAV 2017), held in Toulouse, France. The performance video is available on https://youtu.be/8H19ppS_VXM . 相似文献
2.
面对日益突出的城市静态交通问题,针对普陀区所处的地理位置和发展形势,提出了在普陀区实施静态交通规划(包括技术路线、政策研究及相关的经济分析方法)的初步构想。 相似文献
3.
空间机器人控制语言是实现空间机器人三种控制方式:遥控操作,自主操作和协同操作的软件基础,本文描述了该语言的基本结构,对于自主方式,给出了编程示例;对于遥控方式,运用程序辅助的方法,解决了操作员单独进行主/从操作时难以解决的问题. 相似文献
4.
5.
6.
New small‐scale dispersed generation systems, such as fuel cells and micro gas turbines, have made remarkable advances lately and they will be applied practically in the near future. Although a large number of researches on the introduction of small‐scale dispersed generation systems have been carried out, only a small number of small‐scale dispersed generation systems are considered in these researches. Therefore, little is known about problems to be solved when a large number of small‐scale dispersed generation systems are introduced into electric power systems. This paper deals with a super‐distributed energy system that consists of a great number of dispersed generation systems such as fuel cells, micro gas turbines, and so on. The behavior of a customer with a dispersed generation system is simulated as the Ising model in statistical mechanics. The necessity of a distribution network in super‐distributed energy systems is discussed based on the Ising model. The feasibility of decentralized autonomous control using vicinity information is also investigated on the basis of stability analysis of the Hopfield neural network model. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(1): 43–55, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10368 相似文献
7.
Photovoltaic (PV) cells, when integrated within a building facade, offer the possibility of generating electric power and heat for local use or export. This paper reports on a project to investigate the practical operational efficiencies that might be delivered from such facades. The results from laboratory experiments and computer simulations are presented: the former were used to develop an empirical relationship between cell temperature and power output; the latter were undertaken to assess operational efficiencies under a range of climate conditions representative of the UK. 相似文献
8.
针对当前城市中普遍存在的停车难及停车场管理不规范的问题,提出了一种基于ZigBee技术的智能停车场管理系统。该系统采用125kHz激励器唤醒载有2.4GHz高频电子标签以及语音播报模块的车载单元,结合红外线反射性传感器和CC2530实现停车定位,并通过ZigBee无线通信网络实现车辆和控制中心的交互,从而实现无障碍智能停车场管理。本方法比传统的停车场管理方式更加准确、便捷、高效。 相似文献
9.
为了提高自动驾驶汽车环境感知的性能,增强单目相机对障碍物三维和边界信息的感知能力,提出了一种基于地面先验的3D目标检测算法。基于优化的中心网络(CenterNet)模型,以DLA(deep layer aggregation)为主干网络,增加目标3D边沿框中心点冗余信息预测。根据自动驾驶场景的地面先验信息,结合针孔相机模型,获取目标3D中心深度信息,以优化深度网络学习效果。使用KITTI 3D数据集评测算法性能,结果表明:在保证2D目标检测准确性的基础上,该算法运行帧率约20 fps,满足自动驾驶感知实时性要求;同时相比于CenterNet模型,在平均方位角得分(average orientation score)和鸟视图平均准确率(bird eye view AP)上分别有4.4和4.4%的性能提升。因而,该算法可以提高自动驾驶汽车对障碍物三维和边界信息的感知能力。 相似文献
10.
Nikolaos G. Bourbakis 《Journal of Intelligent and Robotic Systems》1989,1(4):375-387
In this paper, a heuristic and learning, algorithmic scheme for collision-free navigation is presented. This scheme determines an optimum collision-free navigation path of an autonomous platform by using a trial and error process, past navigation knowledge and current information extracted from the generated surrounding environment. 相似文献