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61.
Reconfigurable control as actuatorfault-tolerant control design for poweroscillation damping 下载免费PDF全文
This paper presents design of an self contained actuators unit in wide area damping control of power system in
stabilizing system response for both nominal system condition and during actuator faults. First it is presented that use
of multiple actuators in wide area control aid in improving damping in power system. A wide area damping controller
feeding multiple actuators to satisfy multiple objectives in wide area damping control of power system is designed.
Minimization of infinity norm of closed loop transfer function of power system with wide area controller in feedback
path & closed loop poles placement techniques are used in controller synthesis. Second a reconfigurable control on
the lines of fault hiding principle is added to the controller design to maintain system damping to pre-fault level in
case of actuator faults. A reconfiguration component(RC) is activated on occurrence of actuator fault thereby
reconfiguring system dynamics and redistributing wide area control signal among remaining active actuators. RC
together with remaining active actuators and under same wide area damping controller maintains system damping to
pre-fault level thereby preserving system dynamic response. In the reconfigurable control design presented here no
new actuators outside the unit of actuators designed for wide area damping control is required. This makes for an self
contained actuators unit in wide area damping control of power system both for nominal system condition and for
system affected by actuator faults. A two area power system model is considered here for demonstrating effectiveness
of designed robust damping controller with multiple outputs feeding multiple actuators in wide area control and
illustrating the idea of self contained actuators unit for maintaining system damping in case of actuator faults. 相似文献
62.
某动力厂 12 0m高混凝土烟囱采用滑模施工 ,在 73 3~ 97 7m标高处 ,烟囱中心偏差严重超标 ,造成质量事故。在事故处理过程中 ,利用原有滑模体系将该段混凝土壁顺利拆除 ,并采取措施保证了施工质量 相似文献
63.
In this paper, an active fuzzy fault tolerant tracking control (AFFTTC) scheme is developed for a class of multi-input multi-output (MIMO) unknown nonlinear systems in the presence of unknown actuator faults, sensor failures and external disturbance. The developed control scheme deals with four kinds of faults for both sensors and actuators. The bias, drift, and loss of accuracy additive faults are considered along with the loss of effectiveness multiplicative fault. A fuzzy adaptive controller based on back-stepping design is developed to deal with actuator failures and unknown system dynamics. However, an additional robust control term is added to deal with sensor faults, approximation errors, and external disturbances. Lyapunov theory is used to prove the stability of the closed loop system. Numerical simulations on a quadrotor are presented to show the effectiveness of the proposed approach. 相似文献
64.
The 2-degree of freedom (DOF) helicopter system is a typical higher-order, multi-variable, nonlinear and strong coupled control system. The helicopter dynamics also includes parametric uncertainties and is subject to unknown external disturbances. Such complicated system requires designing a sophisticated control algorithm that can handle these difficulties. This paper presents a new robust control algorithm which is a combination of two continuous control techniques, composite nonlinear feedback (CNF) and super-twisting control (STC) methods. In the existing integral sliding mode (ISM) based CNF control law, the discontinuous term exhibits chattering which is not desirable for many practical applications. As the continuity of well known STC reduces chattering in the system, the proposed strategy is beneficial over the current ISM based CNF control law which has a discontinuous term. Two controllers with integral sliding surface are designed to control the position of the pitch and the yaw angles of the 2- DOF helicopter. The adequacy of this specific combination has been exhibited through general analysis, simulation and experimental results of 2-DOF helicopter setup. The acquired results demonstrate the good execution of the proposed controller regarding stabilization, following reference input without overshoot against actuator saturation and robustness concerning to the limited matched disturbances. 相似文献
65.
可控硅脉冲调速方式具有启动牵引力大,调速均匀,无电能损耗,能实现无级启动等特点,极大地改善了矿用电机车的启动和调速性能。但在可控硅脉冲调速过程中出现的失控现象,常会使电机车损坏或者造成运输事故。因此,分析脉冲调速中的失控故障现象,并且采取相应的处理措施,才能保证矿用电机车的正常运行,以实现煤矿的安全生产。 相似文献
66.
介绍了西曲矿选煤厂对原来分流机构的改造,将原来的分流箱改成了分流管,取得了显著效果,解决了因为分流箱执行机构动作不灵而致使分流效果不佳的问题。 相似文献
67.
为研究介电型EAP摆动驱动器的性能,设计制作了柔杆式介电型EAP摆动驱动器。对驱动器的摆动性能进行了测试,获得了不同施加电压下驱动器的摆动角度与阻转力。结果表明,随着施加电压的增加,驱动器的摆动角度、阻转力也在增加,且在电压较大时增加更快。此外,EAP的拉伸率对驱动器性能也有一定的影响,并指出了该驱动器在结构与性能优化的基础上,可潜在用于仿生机器人的摆动驱动。 相似文献
68.
介绍蓄能器的结构与应用,引用实例分析蓄能器在液压系统中的作用,得出该系统下的气压计算结果,针对矿用乳化液泵蓄能器使用中常见的问题,分析出现故障的原因,提出处理方法。 相似文献
69.
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