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Recovering node parameters and topologies of uncertain non-linearly coupled complex networks 期刊论文  OAI收割
IET CONTROL THEORY AND APPLICATIONS, 2020, 卷号: 14, 期号: 1, 页码: 105-115
作者:  
Wang, Xiong;  Gu, Haibo;  Chen, Yao;  Lu, Jinhu
  |  收藏  |  浏览/下载:68/0  |  提交时间:2020/05/24
Modeling and variable structure control of a vehicle flexible manipulator (EI CONFERENCE) 会议论文  OAI收割
10th World Congress on Intelligent Control and Automation, WCICA 2012, July 6, 2012 - July 8, 2012, Beijing, China
作者:  
Wang Z.;  Li Y.;  Li Y.;  Li Y.;  Li Y.
收藏  |  浏览/下载:23/0  |  提交时间:2013/03/25
In this paper  the mathematical modeling and the application of a new trajectory tracking control technique for hydraulic-driven rigid-flexible manipulator are concerned. To get a closer dynamic behavior of the real system  both the flexible manipulator linkage and the actuator dynamics are considered. The exact dynamic model of flexible manipulator is derived using Lagrange principle and assumed modes method. The partial decoupled dynamic equation is derived using nonlinear decoupling feedback control method. The whole dynamic model is established by a driven Jacobin matrix  which represents the coupling between hydraulic servo system and mechanical system. A variable structure controller with inverse dynamics is designed for trajectory tracking. To weaken the chattering of control signal  saturation function is used to instead of sign function. The experimental results investigate the effectiveness of the proposed approaches. 2012 IEEE.  
Land use dynamics and landscape change pattern in Hetao irrigation district, Inner Mongolia, China 会议论文  OAI收割
6th International Symposium on Digital Earth: Data Processing and Applications, Beijing, China, September 9, 2009 - September 12,2009
Zhang, Yinhui; Luo, Yi; Zhao, Wenwu
收藏  |  浏览/下载:28/0  |  提交时间:2014/12/07
This study analyzed spatial and temporal changes in land use in an irrigation district covering an area of 1.7 million ha in Northern China by GIS analyses and also investigated changes in landscape pattern using the landscape structure analysis program FRAGSTATS over the study period from 1986 to 2000. The decreases in farmland and the increases in grassland area mainly resulted from the policy of grain for green and converting slope farmland into pasture from China government. In spite of the efforts to conserve the fragile ecosystem  the land degradation  including soil salinization and grassland degradation  was spreading rapidly. The area of alkali-saline land increased by 22493 ha and about 50555 ha of dense grassland degraded into mid-density grassland. In terms of landscape fragmentation  both farmland and dense grassland showed the tendency of increased fragmentation. Both adverse natural conditions and human activities are responsible for the land degradation expansion in Hetao irrigation district  but the root causes are increasing population pressure and irrational human activities  such as flooding irrigation method and over-grazing. To prevent land degradation from spreading  population control and improvement of the management are prerequisite approaches. 2010 SPIE.  
Hierarchical sliding mode control for a class of SIMO under-actuated systems 期刊论文  OAI收割
CONTROL AND CYBERNETICS, 2008, 卷号: 37, 期号: 1, 页码: 159-175
作者:  
Qian, Dianwei;  Yi, Jianqiang;  Zhao, Dongbin
收藏  |  浏览/下载:39/0  |  提交时间:2015/11/08
Chip design of linear CCD drive pulse generator and control interface (EI CONFERENCE) 会议论文  OAI收割
2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies - Advanced Optical Manufacturing and Testing Technologies, November 2, 2005 - November 5, 2005, Xian, China
作者:  
Sun H.;  Wang Y.;  Wang Y.;  Wang Y.;  Wang Y.
收藏  |  浏览/下载:31/0  |  提交时间:2013/03/25
CCD noises and their causes are analyzed. Methods to control these noises  such as Correlated Double Sampling (CDS)  filtering  cooling  clamping  and calibration are proposed. To improve CCD sensor's performances  the IC  called Analog Front End (AFE)  integration of CDS  clamping  Programmable Gain Amplifier (PGA)  offset  and ADC  which can fulfill the CDS and analog-to-digital conversion  is employed to process the output signal of CCD. Based on the noise control approaches  the idea of chip design of linear CCD drive pulse generator and control interface is introduced. The chip designed is playing the role of (1) drive pulse generator  for both CCD and AFE  and (2) interface  helping to analysis and transfer control command and status information between MCU controller and drive pulse generator  or between global control unit in the chip and CCD/AFE. There are 6 function blocks in the chip designed  such as clock generator for CCD and AFE  MCU interface  AFE serial interface  output interface  CCD antiblooming parameter register and global control logic unit. These functions are implemented in a CPLD chip  Xilinx XC2C256-6-VQ100  with 20MHz pixel frequency  and 16-bit high resolution. This chip with the AFE can eliminate CCD noise largely and improve the SNR of CCD camera. At last  the design result is presented.  
Using one-dimensional nonlinear photonic crystal for dynamical addressing optical interconnection (EI CONFERENCE) 会议论文  OAI收割
ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China
作者:  
Li C.;  Wang W.;  Wang W.;  Li C.;  Li C.
收藏  |  浏览/下载:36/0  |  提交时间:2013/03/25
Optical interconnection is the key technique of high-speed optical information process and optical communication. A lot of approaches for optical interconnection have been proposed since Goodman in Stanford University firstly proposed the optical interconnection for very large scale integrated circuits technology. A dynamical addressing device for optical interconnection was designed and fabricated in this paper. This optical device is based on one-dimensional nonlinear photonic crystal made on the planar waveguide. The nonlinear materials ZnS and ZnSe  which have large nonlinear refractive index coefficients  were alternately deposited on the waveguide to form one-dimensional photonic crystal. The Bragg condition is changed when the input power of the control light increased due to the nonlinear characters of the materials  thus the reflective angle of the signal light can be changed with the input power change of the control light. In our experiment  when increasing the power density of control light from 0 to 2.60X105W/cm 2  the angle of the signal beam can be changed about 20. The interconnection characteristics were investigated in theory and in experiment. The testing data agree well with theoretical predictions. This kind of devices is promising to use in the all-optical interconnection  optical information processing and optical communication.