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1.
2.
Key areas of robot agility include methods that increase capability and flexibility of industrial robots and facilitate robot re-tasking. Manual guidance can achieve robot agility effectively, provided that a safe and smooth interaction is guaranteed when the user exerts an external force on the end effector. We approach this by designing an adaptive admittance law that can adjust its parameters to modify the robot compliance in critical areas of the workspace, such as near and on configuration singularities, joint limits, and workspace limits, for a smooth and safe operation. Experimental validation was done with two tests: a constraint activation test and a 3D shape tracing task. In the first one, we validate the proper response to constraints and in the second one, we compare the proposed approach with different admittance parameter tuning strategies using a drawing task where the user is asked to guide the robot to trace a 3D profile with an accuracy or speed directive and evaluate performance considering path length error and execution time as metrics, and a questionnaire for user perception. Results show that appropriate response to individual and simultaneous activation of the aforementioned constraints for a safe and intuitive manual guidance interaction is achieved and that the proposed parameter tuning strategy has better performance in terms of accuracy, execution time, and subjective evaluation of users. 相似文献
3.
This paper demonstrates a haptic device for interaction with a virtual environment. The force control is added by visual feedback
that makes the system more responsive and accurate. There are two popular control methods widely used in haptic controller
design. First, is impedance control when user motion input is measured, and then, the reaction force is fed back to the operator.
The alternative method is admittance control, when forces exerted by user are measured and motion is fed back to the user.
Both, impedance and admittance control are also basic ways for interacting with a virtual environment. In this paper, several
experiments were performed to evaluate the suitability of force-impedance control for haptic interface development. The difference
between conventional application of impedance control in robot motion control and its application in haptic interface development
is investigated. Open loop impedance control methodology is implemented for static case and a general-purpose robot under
open loop impedance control was developed as a haptic device, while a closed loop model based impedance control was used for
haptic controller design in both static and dynamic case. The factors that could affect to the performance of a haptic interface
are also investigated experimentally using parametric studies. Experimental results for 1 DOF rotational motion and 2 DOF
planar translational motion systems are presented. The results show that the impedance control aided by visual feedback broaden
the applicability of the haptic device and makes the system more responsive and accurate.
相似文献
J. SasiadekEmail: |
4.
正确认知射频导纳液位计 总被引:1,自引:0,他引:1
以DREXELBROOK公司的射频导纳液位计为例,从概念、结构、原理和应用几方面对射频导纳液位计进行了一系列剖析,以便使人们了解射频导纳液位计的本质,消除一些错误认识,从而更好地发挥其作用。 相似文献
5.
Guocai Wang Longzhu Chen Chunyu Song 《International journal for numerical methods in engineering》2006,67(7):916-932
The formulations of axisymmetrically infinite elements for dynamic analysis of vertical vibration problems in unbounded saturated composite foundations are presented. The theoretical basis as well as the implementation of the elements is discussed, and the element decay functions are derived using the analytical solutions of axially symmetric configurations. Using the proposed finite–infinite element method, the surface vertical displacements of air‐saturated soil (‘dry’ soil) and of water‐saturated soil with extremely low permeability subjected to a surface point excitation (called as the Lamb's problem) are calculated and the results agree very well with the existing theoretical solutions of single‐phase elastic media. As an application, the velocity admittances of a concrete block resting on cement mixing‐pile or gravel‐pile saturated composite foundations are calculated. The influence of soil permeability and pile rigidity on the dynamic response of the composite foundations is investigated. The method proposed by this paper is a simple and reliable numerical one that could be used to study axisymmetrically dynamic problems of layered saturated media and to get the mechanism of dynamic testing on single‐pile saturated composite foundations. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
6.
基于节点导纳方程的故障定位及仿真 总被引:1,自引:1,他引:1
根据频域故障传输线的分布参数节点导纳方程推导了一种双短故障测距方法。该方法可以对不对称故障进行定位,这些故障包括单相接地故障、两相接地故障和两相短路故障;而且不要求传输线分布参数对称,不受系统阻抗的影响,不受过渡阻抗的影响。 相似文献
7.
本文以静态Ward等值法为基础,结合模糊数学理论应用灵敏度分析法,提出了一种新的静态等值方法.例系统计算结果表明,本文提出的方法具有较好的准确度. 相似文献
8.
应用电路原理,论述含有多个理想运算放大器网络的机辅分析方法。完善自行编制的SPFD电路分析程序。重点介绍程序中建立电路方程的功能;提供实用的算法及信号流程图。 相似文献
9.
星形延边三角形接线平衡变压器的阻抗匹配与数学模型 总被引:17,自引:5,他引:17
星形延边三角形接线平衡变压器是应用于我国电气化铁道的一种新型三相一两相平衡变压器。针对其特殊的接线形式,提出了以磁势平衡方程、绕组连接方程、端口输出方程和电压传递方程为基础的多绕组变压器系统化分析方法。根据理想平衡变压器的技术条件提出了基于绕组之间短路阻抗的阻抗匹配关系式,推广了以前的有关结论。讨论了星形延边三角形接线平衡变压器的等值模型、两相等值电路和中性点不接地运行等问题。给出了星形延边三角形接线平衡变压器在相坐标下的节点导纳矩阵,以便与电力系统其它部分接口进行有关分析。 相似文献
10.