中国科学院机构知识库网格系统: 检索

A New Technique to Diagnose the Geomagnetic Field Based on a Single Circular Current Loop Model 期刊论文 OAI收割
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH, 2021, 卷号: 126, 期号: 11, 页码: 15
作者: Rong, Z. J.; Wei, Y.; Klinger, Lucy; Yamauchi, M.; Xu, W. Y.

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收藏 | 浏览/下载：58/0 | 提交时间：2022/07/04

geomagnetic field dipole field spherical harmonic analysis current loop dynamo currents planetary magnetic field

7T Transmit/Receive Arrays Using ICE Decoupling for Human Head MR Imaging 期刊论文 OAI收割
IEEE TRANSACTIONS ON MEDICAL IMAGING, 2014, 卷号: 33, 期号: 9, 页码: 1781-1787
作者: Yan XQ(燕新强); Yan, XQ; Feng BT(丰宝桐); Zhang, XL; Feng, BT

收藏 | 浏览/下载：40/0 | 提交时间：2016/04/08

Decoupling high field magnetic resonance imaging (MRI) human head induced current compensation or elimination (ICE) loop parallel imaging phased array radio-frequency (RF) coil

LABTM control system based on FPGA (EI CONFERENCE) 会议论文 OAI收割
2nd International Conference on Mechatronics and Applied Mechanics, ICMAM 2012, December 8, 2012 - December 9, 2012, Taiwan
作者: Wang Y.; Yu P.; Yu P.; Wang Y.; Wang Y.

收藏 | 浏览/下载：156/0 | 提交时间：2013/03/25

This paper presents the digital PI control method for design and simulation of a high precision limited angle brushless torque motor control system in Field Programmable Gate Array device (FPGA). The direct drive structures which are widely applied in many servo control fields. Matlab Xilinx System GeneratorR toolbox based on Fixed-Point Arithmetic is used to design the digital PI controller using DSP architecture plot the responses of the control system and generate the VHDL source code. The control system model consists of a digital PI a real LABTM and a real absolute Inductosyn encoder to rpm and position blocks. Through loading generated codes in process of the simulation that built by the digital discrete model it is verified that the rising time of current loop is only 1.2ms and rate loop is 8ms overshoot is rarely 4.2%. Finally the comprehensive positioning accuracy of system can reach up to 5 arc sec and the rate jitter achieves 5% with the 4 arc sec accuracy absolute Inductosyn. (2013) Trans Tech Publications Switzerland.

Kinetic Alfven wave instability driven by a field-aligned current in high-beta plasmas 期刊论文 OAI收割
PHYSICAL REVIEW E, 2011, 卷号: 84, 期号: 4, 页码: 046406
作者: Chen, L.; Wu, D. J.; Hua, Y. P.

收藏 | 浏览/下载：33/0 | 提交时间：2012/08/07

CORONAL LOOP OSCILLATIONS ELECTRON ACCELERATION NONLINEAR EXCITATION TRANSITION-REGION HOSE INSTABILITY SOLAR ATMOSPHERE MODE CONVERSION MAGNETIC-FIELD CURRENT SHEETS HEAVY-IONS

The technique of camera scan control based on current loop control (EI CONFERENCE) 会议论文 OAI收割
2011 International Conference on Electronics and Optoelectronics, ICEOE 2011, July 29, 2011 - July 31, 2011, Dalian, China
作者: Liu Z.

收藏 | 浏览/下载：22/0 | 提交时间：2013/03/25

As the crucial structure of aerial camera sca reflector is always requested with high performance of control precision stable running and rapid responding. The paper introduces a kind of method about current loop control system which is based on position and velocity dual-closed loop control system. This method improves effectively the performance of velocity closed loop control system and amplifies the gain of low frequency. The results show applying these control methods the influence of the torque ripple has decrease 50% and the compensation rate precsion has promoted double. 2011 IEEE.

The ship-borne infrared searching and tracking system based on the inertial platform (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Li Y.; Zhang H.; Zhang H.; Li Y.; Li Y.

收藏 | 浏览/下载：41/0 | 提交时间：2013/03/25

As a result of the radar system got interferenced or in the state of half silent it can cause the guided precision drop badly In the modern electronic warfare therefore it can lead to the equipment depended on electronic guidance cannot strike the incoming goals exactly. It will need to rely on optoelectronic devices to make up for its shortcomings but when interference is in the process of radar leading especially the electro-optical equipment is influenced by the roll pitch and yaw rotation it can affect the target appear outside of the field of optoelectronic devices for a long time so the infrared optoelectronic equipment can not exert the superiority and also it cannot get across weapon-control system "reverse bring" missile against incoming goals. So the conventional ship-borne infrared system unable to track the target of incoming quickly the ability of optoelectronic rivalry declines heavily.Here we provide a brand new controlling algorithm for the semi-automatic searching and infrared tracking based on inertial navigation platform. Now it is applying well in our XX infrared optoelectronic searching and tracking system. The algorithm is mainly divided into two steps: The artificial mode turns into auto-searching when the deviation of guide exceeds the current scene under the course of leading for radar.When the threshold value of the image picked-up is satisfied by the contrast of the target in the searching scene the speed computed by using the CA model Least Square Method feeds back to the speed loop. And then combine the infrared information to accomplish the closed-loop control of the infrared optoelectronic system tracking. The algorithm is verified via experiment. Target capturing distance is 22.3 kilometers on the great lead deviation by using the algorithm. But without using the algorithm the capturing distance declines 12 kilometers. The algorithm advances the ability of infrared optoelectronic rivalry and declines the target capturing time by using semi-automatic searching and reliable capturing-tracking when the lead deviation of the radar is great. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

A brushless DC motor controller with current-loop control (EI CONFERENCE) 会议论文 OAI收割
2nd Annual Conference on Electrical and Control Engineering, ICECE 2011, September 16, 2011 - September 18, 2011, Yichang, China
Gao S.

收藏 | 浏览/下载：33/0 | 提交时间：2013/03/25

This paper presents a brushless DC motor controller with current loop control. The controller applies a complementary PWM modulation scheme to the power MOSFET. The current processor employed by the controller could detect the current flow through the motor windings accurately and convert the current to a voltage input to the error amplifier. The controller has 100% duty cycle high side conduction capability and real four quadrant torque control capability. It is able to implement a tight torque control for a DC brushless motor to satisfy the need of some servo system which calls for high bandwidth and raid dynamic response. 2011 IEEE.

A physical explanation of solar microwave Zebra pattern with the current-carrying plasma loop model 期刊论文 OAI收割
ASTROPHYSICS AND SPACE SCIENCE, 2010, 卷号: 325, 期号: 2, 页码: 251-257
作者: Tan, Baolin

收藏 | 浏览/下载：28/0 | 提交时间：2017/04/18

Solar microwave emission Zebra pattern structure Electric current loop Flare

Position servo control of a DC electromotor using a hybrid method based on model reference adaptive control (MRAC) (EI CONFERENCE) 会议论文 OAI收割
2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China
作者: Chen J.

收藏 | 浏览/下载：27/0 | 提交时间：2013/03/25

This paper dealed with position control problems of a DC motor servo system that had nonlinear friction and was subject to parametric uncertainties external disturbances etc. In order to overcame those unfavourable factors mentioned above a model reference adaptive control method was proposed to regulate the important and main speed loop in the positioning system which was designed with three closed control loop where a compensatory measure was given so as to counterbalance the friction torque disturbances. In addition the other two close loops were built in adjusting the position and the current of the servo system respectively that aimed to achieve the fast and precise positioning and increase dynamic stiffness against load disturbances. Experimental results illustrate satisfactory performances in steady state error load capability high rapidity and so on. 2010 IEEE.

Persistent spin current in a quantum-dot ring with Rashba spin-orbit coupling 期刊论文 OAI收割
Physics Letters A, 2009, 卷号: 373, 期号: 18-19, 页码: 1672-1678
G. Y. Yi; Y. Han; W. J. Gong; H. N. Wu; G. Z. Wei

收藏 | 浏览/下载：15/0 | 提交时间：2012/04/13

Quantum-dot ring Green's function Persistent spin current phase-factors berrys phase loop transport single