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2010 International Conference on Microwave and Millimeter Wave Technology, ICMMT 2010

作者： Wei, Xue Xiaoniu, Yang Zhaoyang, Zhang National Laboratory of Information Control Technology for Communication System Jiaxing Zhejiang 314033 China Department of Information Science and Electronic Engineering Zhejiang Uinversity Hangzhou Zhejiang 310027 China

ISBN: (纸本)9781424457052

The constant modulus algorithm (CMA) is one widely used algorithm for blind equalization of quadrature amplitude modulation (QAM) signals. The algorithm exhibits slow convergence rate and large steady state mean square error and the phase blind nature in comparison with the algorithms used in conventional data-aided equalization schemes. In this paper, a variable step size modified constant modulus algorithm is proposed. The proposed algorithm can achieve fast convergence rate and decrease steady state mean square error and correct phase shift and carrier frequency offset at the same time. The simulation results demonstrate the effectiveness of the proposed algorithm in improving convergence behavior and bit error rate performance. © 2010 IEEE.

关键词： Blind equalization

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A stop and go blind equalization algorithm for QAM signals

A stop and go blind equalization algorithm for QAM signals

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International Conference on Wireless Communications, Networking and Mobile Computing (WiCom)

ISBN: (纸本)9781424437092

The constant modulus algorithm (CMA) has been widely used in the blind equalization of quadrature amplitude modulation (QAM) signals, but it has slow convergence rate and large steady state mean square error and the phase blind nature. In this paper, a modified constant modulus algorithm which incorporates a stop and go technique is proposed. The proposed algorithm can speed up convergence rate and decrease steady state mean square error and correct phase error and frequency offset simultaneously. The simulation results demonstrate the effectiveness of the proposed algorithm in improving convergence behavior and bit error rate (BER) performance. © 2010 IEEE.

关键词： Blind equalization

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A carrier recovery algorithm for high order QAM signals

A carrier recovery algorithm for high order QAM signals

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International Conference on Wireless Communications, Networking and Mobile Computing

作者： Xue, Wei Yang, Xiaoniu Zhang, Zhaoyang National Laboratory of Information Control Technology for Communication System Jiaxing Zhejiang 314033 China Department of Information Science and Electronic Engineering Zhejiang Uinversity Hangzhou Zhejiang 310027 China

ISBN: (纸本)9781424437092

The carrier recovery is one key technique in the demodulation of high order quadrature amplitude modulation (QAM) signals. A carrier recovery algorithm which switches between multi-threshold polarity decision mode and decision directed mode according to the standard deviation of the frequency of numerically controlled oscillator (NCO) is proposed. The proposed algorithm can detect a proper time for the mode switch to yield lower steady state error. The simulation results demonstrate the effectiveness of the proposed algorithm in improving the performance of blind carrier recovery. © 2010 IEEE.

关键词： Quadrature amplitude modulation

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Analysis on the reflection coefficient of irregular wave by perforated breakwaters with superstructure

Analysis on the reflection coefficient of irregular wave by ...

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20th International Offshore and Polar engineering Conference, ISOPE-2010

作者： Chen, Xuefeng Li, Kong Li, Yucheng Key Laboratory for Prediction and Control on Complicated Structure System of the Education Department of Liaoning Province Dalian University Dalian China State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian Liaoning China

ISBN: (纸本)9781880653777

Irregular wave acting on the superstructure of the perforated breakwaters is simulated through numerical wave flume. And the reflection coefficient in front of perforated structure is analysed. VOF method is utilized to solve the Reynolds-averaged Navier-Stokes equation (RANS) and the k-Ε model. In order to simulate successive long-time making wave of irregular waves and absorb the reflected waves from the perforated breakwaters, the internal source generation of wave is applied. An air state equation under the constant temperature condition is used to simulate the air pressure in the chamber when the hole of perforated plate is full of the water. According to the comparison between the numerical result and test data, it is seen that the numerical model is well verified by the experimental data. Then an empirical expression for computing the reflection coefficient is obtained from the linear regression with the main related parameters. The expressions of these empirical relations are simple and useful for actual engineering design. © 2010 by The International Society of Offshore and Polar Engineers (ISOPE).

关键词： Reflection

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Discussion on setting calculation of loss-of-excitation protection for large turbogenerator

Discussion on setting calculation of loss-of-excitation prot...

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2010 International Conference on Electrical Machines and systems, ICEMS2010

作者： Yao, Siwang Wang, Weijian Luo, Ling Gui, Lin Qiu, Arui State Key Laboratory of Control and Simulation of Power System and Generation Equipments Department of Electrical Engineering Tsinghua University Beijing China

Loss of excitation (LOE) is a common fault found in the generators. The most widely applied method for detecting a generator loss of excitation is the use of impedance relays to sense the variation of impedance as viewed from the generator terminals [1]. However, compared with China's approachs, in the setting of impedance circle, the IEEE's allow the circle to extend along the negative X axis, meanwhile, in the latest edition of the "IEEE Guide for AC Generator Protection", the circle is further extended, reaching to -1.25X_d.We think this is adverse, to prove our point, the paper ,basing on the IEEE 9 bus model and using computer digital simulation, have studied various loss-of-excitation conditions and some system disturbances that may lead to the relay false tripping. Simulation results indicate that the IEEE's method not only can't accelerate the operation effectively, but also will increase the chances of maloperation.

关键词： Impedance Generators Relays Analytical models Power system stability Reactive power

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Tailor-made modeling and sway control of human posture riding on electrical wheelchair for comfort driving

Tailor-made modeling and sway control of human posture ridin...

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2010 IEEE/RSJ International Conference on Intelligent Robots and systems

作者： Koumei Yamashita Yoshiyuki Noda Takanori Miyoshi Kazuhiko Terashima System and Control Laboratory Production System Engineering Toyohashi University of Technology Toyohashi Aichi Japan

This paper gives an advanced driving control system that considers sway suppression of a passenger's posture in an electrical wheelchair. We proposed a passenger model that considers the passenger's physical frame and seating condition. The passenger's seating condition is classified as upright, standard, or round-shouldered posture. The sway of a passenger with round-shouldered posture is smaller than that of a passenger with upright posture, and they can be represented by the proposed model. To suppress the sway of a wheelchair passenger's posture, the wheelchair driving pattern is optimized using the proposed passenger's posture model. The comfort of the passenger with respect to the proposed wheelchair driving is evaluated through experiments.

关键词： Wheelchairs Torso Springs Gravity Acceleration Mathematical model Joints

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Research on data-based nonlinear fault prediction theory and methods in multi-transform domains for electromechanical equipment

Research on data-based nonlinear fault prediction theory and...

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23rd International Congress on Condition Monitoring and Diagnostic engineering Management, COMADEM 2010

作者： Wang, Shaohong Chen, Tao Xu, Xiaoli School of Mechanical and Vehicular Engineering Beijing Institute of Technology Beijing China Beijing Key Laboratory on Measurement and Control of Mechanical and Electrical System Beijing Information Science and Technology University Beijing China

ISBN: (纸本)9784883254194

Most faults of large-scale electromechanical equipment are trendy ones, often have long course characteristics. As the fault information is usually lost in non-fault information of condition changes, the traditional methods are difficult to predict it effectively. To solve this problem, field data-based fault prediction theory and methods are studied primary for large rotating electromechanical equipment, and new nonlinear prediction way in multi-transform domains is proposed to achieve long course prediction for the equipment under variable operating conditions. In the new way fault feature extraction method of nonlinear dimensionality reduction is investigated to extract fault and potential fault sensitive information and to separate faulty development changes from non-fault energy changes. The research is important for large electromechanical equipment to achieve early fault prediction, guarantee safe operation, save maintenance costs, improve utilization and implement scientific maintenance.

关键词： Feature extraction

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Single sensor information fusion for local fault prediction of large rotating machinery

Single sensor information fusion for local fault prediction ...

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International Conference on Electrical and control engineering, ICECE 2010

作者： Jianghong, Sun Yunbo, Zuo Xu, Xiaoli School of ElectroMechanical Engineering Beijing Information Science and Technology University Beijing China School of Mechanical and Vehicular Engineering Beijing Institute of Technology Beijing China Beijing Key Laboratory - Measurement and Control of Mechanical and Electrical System Beijing China

ISBN: (纸本)9780769540313

Data process of large rotating machinery is in line with basic features of information fusion. A framework of fault diagnosis and prediction based on sensor information fusion is built. An improved extracting method of features is used to deal with the information fusion of single sensor, which raises the calculation efficiency and precision. The local fault prediction process is presented, and the fault deterioration trend is judged on the basis of dynamic weighted method. Actual example of Beijing Yanshan Petrochemical Co. shows the correction of conclusion. © 2010 Crown.

关键词： Information fusion

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A study based on DC chopper excitation system

A study based on DC chopper excitation system

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作者： Zhang, Guofei Wang, Huilin Key Laboratory of Power System Protection and Dynamic Security Monitoring and Control School of Electrical and Electronic Engineering North China Electric Power University Beijing 102206 China

ISBN: (纸本)9789810863227

A new self-shunt excitation control method has been brought in this paper, which is about how to use DC chopper that is composed with full controlled switch device IGBT to regulate exciting voltage. This new method replaces traditional method which is adopted controlled rectifier by thyristor. Exciting voltage refers from terminal voltage by exciting transformer, and then it goes through uncontrollable rectifier circuit and switches to DC voltage. This DC voltage is used for DC chopper. We can control duty cycle of IGBT to change output voltage and hold terminal voltage steady. In this paper, the conclusion of DC chopper output current proportioned with duty cycle is proved by simulation in PSCAD. And it also proves that it can maintain terminal voltage stability in steady state operation by the control of trigger angle of IGBT. ©Memetic Computing Society.

关键词： Problem solving

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New development thoughts on the bio-inspired intelligence based control for unmanned combat aerial vehicle

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Science China(Technological Sciences) 2010年第8期53卷 2025-2031页

作者： DUAN HaiBin 1 ,SHAO Shan 2 ,SU BingWei 3 &ZHANG Lei 41 State Key laboratory of Science and Technology on Holistic Flight control,School of Automation Science and Electrical engineering, Beijing University of Aeronautics and Astronautics,Beijing 100191,China 2 Flight control Department,Shenyang Aircraft Design and Research Institute,Shenyang 110035,China 3 Beijing Institute of Near Space Vehicle’s system engineering,Beijing 100076,China 4Integration and Project Section,Air Force Equipment Academy,Beijing 100085,China 1. State Key Laboratory of Science and Technology on Holistic Flight Control School of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China2. Flight Control Department Shenyang Aircraft Design and Research Institute Shenyang 110035 China3. Beijing Institute of Near Space Vehicle’s System Engineering Beijing 100076 China4. Integration and Project Section Air Force Equipment Academy Beijing 100085 China

Bio-inspired intelligence is in the spotlight in the field of international artificial intelligence,and unmanned combat aerial vehicle(UCAV),owing to its potential to perform dangerous,repetitive tasks in remote and hazardous,is very promising for the technological leadership of the nation and essential for improving the security of *** the basis of introduction of bioinspired intelligence and UCAV,a series of new development thoughts on UCAV control are proposed,including artificial brain based high-level autonomous control for UCAV,swarm intelligence based cooperative control for multiple UCAVs,hy-brid swarm intelligence and Bayesian network based situation assessment under complicated combating environments, bio-inspired hardware based high-level autonomous control for UCAV,and meta-heuristic intelligence based heterogeneous cooperative control for multiple UCAVs and unmanned combat ground vehicles(UCGVs).The exact realization of the proposed new development thoughts can enhance the effectiveness of combat,while provide a series of novel breakthroughs for the intelligence,integration and advancement of future UCAV systems.

关键词： bio-inspired intelligence unmanned combat aerial vehicle(UCAV) artificial brain autonomous control bayesian network bio-inspired hardware heterogeneous cooperative control

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