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21.
L. V. Chekalov Yu. I. Gromov V. V. Chekalov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):176-179
Cleaning of TPP flue gases with bag filters capable of pulsed regeneration is examined. A new filtering element with a three-dimensional
filtering material formed from a needle-broached cloth in which the filtration area, as compared with a conventional smooth
bag, is increased by more than two times, is proposed. The design of a new FRMI type of modular filter is also proposed. A
standard series of FRMI filters with a filtration area ranging from 800 to 16,000 m2 is designed for an output more than 1 million m3/h of with respect to cleaned gas. The new bag filter permits dry collection of sulfur oxides from waste gases at TPP operating
on high-sulfur coals. The design of the filter makes it possible to replace filter elements without taking the entire unit
out of service.
__________
Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 43–46. 相似文献
22.
A novel reconfigurable microstrip patch antenna with frequency and polarization diversities is proposed. A U‐slot is incorporated into a square patch, and a PIN diode is utilized to switch the slot on and off, which realizes the frequency diversity characteristic. The polarization diversities among linear polarization (LP), right‐hand circular polarization (RHCP), and left‐hand circular polarization (LHCP) are also obtained by switching three PIN diodes on the slot and the truncating corners of a square patch on and off. The antenna design and experimental results are presented. 相似文献
23.
James A. Cutts Kerry T. Nock Jack A. Jones Guillermo Rodriguez J. Balaram 《Autonomous Robots》1995,2(4):261-282
Planetary aerobots are a new type of telerobotic science platform that can fly and navigate in a dynamic 3-dimensional atmospheric environment, thus enabling the global in situ exploration of planetary atmospheres and surfaces. Aerobots are enabled by a new concept in planetary balloon altitude control, developed at JPL, which employs reversible-fluid changes to permit repeated excursions in altitude. The essential physics and thermodynamics ofreversible-fluid altitude control have been demonstrated in a series of altitude-control experiments conducted in the Earth's atmosphere, which are described. Aerobot altitude-control technology will be important in the exploration of seven planets and satellites in our solar system. Three of these objects—Venus, Mars, and the Saturnian satellite Titan—have accessible solid surfaces and atmospheres dominated by the dense gases nitrogen or carbon dioxide. They will be explored with aerobots using helium or hydrogen as their primary means of buoyancy. The other four planets—Jupiter, Saturn, Uranus, and Neptune—have deep atmospheres that are predominantly hydrogen. It may be possible to explore these atmospheres with aerobots inflated with atmospheric gas that is then radiatively heated from the hotter gaseous depths below. To fulfill their potential, aerobots to explore the planets will need autonomous state estimators to guide their observations and provide information to the altitude-control systems. The techniques of acquiring these data remotely are outlined. Aerobots will also use on board altitude control and navigation systems to execute complex flight paths including descent to the surface and exploiting differential wind velocities to access different latitude belts. Approaches to control of these systems are examined. The application of aerobots to Venus exploration is explored in some detail: The most ambitious mission described, the Venus Flyer Robot (VFR), would have the capability to make repeated short excursions to the high-temperature surface environment of Venus to acquire data and then return to the Earth-like upper atmosphere to communicate and recool its electronic systems. Finally a Planetary Aerobot Testbed is discussed which will conduct Earth atmospheric flights to validate autonomous-state-estimator techniques and flight-path-control techniques needed for future planetary missions. 相似文献
24.
25.
针对拼接结构的高分辨率彩色等离子体大屏幕系统的应用,指出了刷新型电路模式的不足之处,提出了一种混合型模式的驱动电路。从彩色模块ACPDP的结构特性出发,详细讨论了该电路的工作原理,驱动波形以及放电过程。 相似文献
26.
智能机器人研究的进展,趋势与对策 总被引:5,自引:0,他引:5
本文着重介绍了国内外高级机器人的发展趋势,讨论了发展智能机器人技术的对策,有助于对机器人的现状和未来发展的进一步了解。 相似文献
27.
后工业时代米兰单功能城区更新 总被引:1,自引:0,他引:1
在物化的形式上,解释米兰城市发展历史上的单功能城区的改造意义,并由此分析单功能城区更新的经验:单功能城区向混合居住模式的更新是发展方向;城区的功能重新定义对城区发展有重要意义;以新的建设为基础,发展城区自身的特色,做到城市在更新和特色之间的协调。 相似文献
28.
A computationally efficient, obstacle avoidance algorithm for redundant robots is presented in this paper. This algorithm incorporates the neural networks and pseudodistance function D
p in the framework of resolved motion rate control. Thus, it is well suited for real-time implementation. Robot arm kinematic control is carried out by the Hopfield network. The connection weights of the network can be determined from the current value of Jacobian matrix at each sampling time, and joint velocity commands can be generated from the outputs of the network. The obstacle avoidance task is achieved by formulating the performance criterion as D
p>d
min (d
min represents the minimal distance between the redundant robot and obstacles). Its calculation is only related to some vertices which are used to model the robot and obstacles, and the computational times are nearly linear in the total number of vertices. Several simulation cases for a four-link planar manipulator are given to prove that the proposed collision-free trajectory planning scheme is efficient and practical. 相似文献
29.
提出状态空间离散化的思想,建立换热器的动态机理模型,然后通过Simulink模块化进行连接,对换热网络进行动态仿真。在大规模原油换热网络的仿真中,采用存储初值和切断代数环的方法,使换热网络的收敛速度得到了很大的提高,为复杂换热网络的动态仿真和实时优化打下了基础。这种方法,还可适用于一般石油化工过程装置的大规模动态仿真运行中。 相似文献
30.
视觉伺服的乒乓球机器人系统作为典型的"手眼系统",是研究高速视觉感知和快速伺服运动的理想平台,其涉及的高速物体识别跟踪、快速精确轨迹预测及机械臂伺服准确回球等关键技术在工业、军事等领域有广泛的应用前景.本文提出了乒乓球机器人的高速视觉伺服系统实现方法,包括基于特征直方图统计和快速轮廓搜索的目标识别算法,基于模型参数学习和自适应模型调整的物体运动状态估计和轨迹预测算法,及基于轨迹预测的灵巧臂回球规划算法.通过实验验证了各算法的实时性和高效性,并在165cm高的仿人机器人"悟"和"空"上成功实现了双机器人对打和与人对打任务. 相似文献