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排序方式: 共有3693条查询结果,搜索用时 500 毫秒
991.
992.
The galvanostatic polymerization of pyrrole is carried out on stainless steel electrodes using p-toluene sulphonic acid. The morphology of the film is studied from Scanning Electron Microscopy (SEM) measurements while
the nature of the substrate is analysed using Energy Dispersive X-ray Spectroscopy (EDAX) technique. The electrochemical behaviour
is studied using cyclic voltammetry, charge-discharge analysis and impedance spectroscopy. The feasibility of the electrode
for supercapacitor applications is investigated. The specific capacitance is estimated as ∼102 Farads per gram with 103 charge-discharge cycles. A plausible equivalent circuit for the system is proposed and the circuit parameters are obtained
by non-linear regression analysis. 相似文献
993.
A planning and scheduling model is developed for the onsertion-phase in printed circuit board (PCB) assembly. PCBs are manufactured by machines that mount components, such as chips, on a PCB. On an onsertor machine, a certain number of component types can be stored. These components are subsequently used for the production of a certain PCB batch type. This research develops a production planning and scheduling formulation to determine the component–machine allocations, as well as a PCB sequence. Two strategies are proposed; one focusing on minimal number of changeovers (C-strategy), and the other on minimal process time (P-strategy). Both strategies were validated in a pilot study with real company data, with encouraging results for potential implementation. 相似文献
994.
自动铺丝平行等距轨迹规划算法实现 总被引:1,自引:0,他引:1
针对复合材料自动铺丝技术轨迹规划问题,提出了一种新的基于测地线的平行等距轨迹规划算法.该算法首先将已知的第一条轨迹线在曲面上等弧长离散得到若干数据点,然后在数据点处曲线切矢和曲面法矢的向量积方向上利用测地线的短程性获得下一条铺放轨迹上数据点,并利用B样条曲线拟和数据点生成铺放轨迹,最后使轨迹线铺满模具表面.算法中测地线利用微分方程组数值求解得到,以曲面曲线弧长为自变量,可实现等距线求解的自适应步长调整和较高的精度.经实际算例验证,该算法简单实用,精度能够满足铺丝技术工艺要求. 相似文献
995.
用仪器放大器作为可控电压源连接在电路中,清除阻尼,实现LC电路的自由振荡,并利用计算机测量和分析系统-PAKMA,验证实验结果。 相似文献
996.
Zhisheng Lin Haitau Lin Hangbo Xue Chuhua Pan Yuliang Long 《International Journal of Infrared and Millimeter Waves》1998,19(3):551-568
This paper reports an automatical slotted-lin system which has been developed by us. This system is controlled with IBM-PC 80486. Its software is designed with C Language. It can performs a variety of measurements such as high, medium and low SWR measurement, signal source SWR, attenuation, phase shift, scattering coefficient of two port network and dielectric constant measurement etc. rapily, exately and conveniently. In this paper, the hardware composition and software design are described. A series of typical measurement results of SWR at 30MM wave-band are given. This method is adaptable for MM-Wave band and other Micro-wave band. 相似文献
997.
In this paper stabilization of infinite-dimensional undamped
second-order systems is considered in the case where the input
and output operators are collocated. The systems have an infinitenumber of poles and zeros on the imaginary axis. In the casewhere only position feedback is available, a parallel compensatoris effective. The stabilizer is constructed by a P-controllerfor the augmented system which consists of the controlled systemand a parallel compensator. The asymptotic stability of theaugmented system is proved by LaSalle's invariance principleunder compactness of the resolvent. 相似文献
998.
L. Ya. Banakh A. S. Gorobtsov O. K. Chesnokov 《Computational Mathematics and Mathematical Physics》2006,46(12):2124-2128
Systems of differential algebraic equations are examined. A method is proposed for transforming the rectangular matrix of algebraic equations to block diagonal form. This method ensures the prescribed accuracy of the solution with respect to the original system of equations. 相似文献
999.
基于电荷具有离散性的事实对介观电路进行量子化,以介观三环为例研究多环耦合系统中的量子电流增强效应.结果表明,量子电流增强效应不仅存在于耦合双环系统中,而且在金属多环系统中也存在.
关键词:
介观电路
耦合系统
量子电流
增强效应 相似文献
1000.
The paper describes the mechanical design of a parallel manipulator for motions of pure translation, whose kinematic analysis
has shown very good performances such as a large workspace and small overall dimensions of the mobile platform; in particular,
the “Cartesian” structure of the machine allowed to obtain constant accuracy and kinematic properties throughout the workspace.
The structural design has minimized the mass of the moving links and, by the combined use of FEM and multibody codes, allowed
to take into consideration the high stresses coming from inertial forces and to evaluate a-priori the resulting dynamic properties. A physical prototype has just been built in order to validate the developed models and
assess the actual robot performances in real operating conditions.
The present research has been partially co-funded by the Italian Ministry of Research and University and by the Polytechnic
University of Marche under PRIN03 project “Design and prototyping of application-oriented mini-PKM”. 相似文献