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18th Pacific-Asia Conference on Advances in Knowledge Discovery and Data Mining, PAKDD 2014

作者： Tu, Xinhui Luo, Jing Li, Bo He, Tingting Gu, Jinguang College of Computer Science and Technology Wuhan University of Science and Technology Wuhan China Hubei Province Key Laboratory of Intelligent Information Processing and Real-time Industrial System Wuhan China Department of Computer Science Central China Normal University Wuhan China State Key Lab. of Software Engineering Wuhan University Wuhan China

ISBN: (纸本)9783319066042

Most existing language modeling approaches are based on the term independence hypothesis. To go beyond this assumption, two main directions were investigated. The first one considers the use of the proximity features that capture the degree to which search terms appear close to each other in a document. Another one considers the use of semantic relationships between words. Previous studies have proven that these two types of information, including term proximity features and semantic relationships between words, are both useful to improve retrieval performance. Intuitionally, we can use them in combination to further improve retrieval performance. Based on this idea, this paper propose a positional translation language model to explicitly incorporate both of these two types of information under language modeling framework in a unified way. In the first step, we present a proximity-based method to estimate word-word translation probabilities. Then, we define a translation document model for each position of a document and use these document models to score the document. Experimental results on standard TREC collections show that the proposed model achieves significant improvements over the state-of-the-art models, including positional language model, and translation language models. © 2014 Springer International Publishing.

关键词： Information retrieval

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A GA-ACO hybrid algorithm for the multi-UAV mission planning problem

A GA-ACO hybrid algorithm for the multi-UAV mission planning...

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International Symposium on Communications and Information Technologies (ISCIT)

作者： Ke Shang Stephen Karungaru Zuren Feng Liangjun Ke Kenji Terada Department of Information Science and Intelligent System The University of Tokushima Japan State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University China

Multi-UAV mission planning is a combinational optimization problem, that aims at planning a set of paths for UAVs to visit targets in order to collect the maximum surveillance benefits, while satisfying some constraints. In this paper, a genetic algorithm and ant colony optimization hybrid algorithm is proposed to solve the multi-UAV mission planning. The basic idea of the proposed hybrid algorithm is replacing the bad individuals of the GA's population by new individuals constructed by ant colony algorithm. Also, an efficient recombination operator called path relinking is used for mating. A population partition strategy is adopted for improving the evolving efficiency. Experimental results suggested that the proposed hybrid algorithm can solve the test instances effectively in a reasonable time. The comparison study with several existing algorithms shows that the proposed algorithm is competitive and promising.

关键词： Planning Sociology Statistics Genetic algorithms Partitioning algorithms Surveillance Ant colony optimization

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Open Architecture and Its Implementation of Power system Numerical Simulation Software

Open Architecture and Its Implementation of Power System Num...

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2014 International Conference on Artificial,Intelligence and Software Engineering(AISE 2014)

作者： Wen-xin LYU Xin-huan JIANG Qun XU Heng-xu ZHANG Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University Qingdao Power Company Shandong State Grid Corporation of China

An open architecture of power system numerical simulation software is proposed, the interface information between simulation engine and user program is exchanged by Client/Server implementation. The open application program interface is realized by establishing an identical and standardized database(a normalized function interface table) on both sides so that they can understand each other through table searching. The client-side secondary development is not limited to single programming language. Interface software packages have been developed for different programming languages including C++, Matlab and Python. It is verified that the proposed framework has powerful openness as well as flexibility, which will greatly improve the calculating and analyzing capabilities of the power system numerical simulation software.

关键词： Power system Numerical simulation Application program interface(API) Open architecture

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Finger Pinch Force Estimation Through Muscle Activations Using A Surface EMG Sleeve On the Forearm

Finger Pinch Force Estimation Through Muscle Activations Usi...

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IEEE International Conference on Fuzzy systems

作者： Yinfeng Fang Zhaojie Ju Xiangyang Zhu Honghai Liu Intelligent Systems and Biomedical Robotics Group School of Computing University of Portsmouth State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

ISBN: (纸本)9781479920747

For prosthetic hand manipulation, the surface Electromyography (sEMG) has been widely applied. Researchers usually focus on the recognition of hand grasps or gestures, but ignore the hand force, which is equally important for robotic hand control. Therefore, this paper concentrates on the methods of finger forces estimation based on multi-channel sEMG signal. A custom-made sEMG sleeve system omitting the stage of muscle positioning is utilised to capture the sEMG signal on the forearm. A mathematic model for muscle activation extraction is established to describe the relationship between finger pinch forces and sEMG signal, where the genetic algorithm is employed to optimise the coefficients. The results of experiments in this paper shows three main contributions: 1) There is a systematical relationship between muscle activations and the pinch finger forces. 2) To estimate the finger force, muscle precise positioning for electrodes placement is not inevitable. 3) In a multi-channel EMG system, selecting specific combinations of several channels can improve the estimation accuracy for specific gestures.

关键词： Muscles Force Electromyography Electrodes Channel estimation Mathematical model Estimation

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Mechanics analysis of a wheelchair robot with wheel-track coupling mechanism

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Journal of Beijing Institute of Technology 2013年第3期22卷 301-307页

作者：李敬一白阳靳飞王冬晓高学山 Intelligent Robotics Institute Beijing Institute of Technology State Key Laboratory of Robotics and System ( HIT)

A barrier-free wheelchair robot with a mechanism coupled by wheel and track is presen- ted in this paper. Using the wheelchair, the lower limb disabled persons could be more relaxed to take part in outdoor activities whether on flat ground or stairs and obstacles in the city. The wheel- track coupling mechanism is designed and the stability of the bodywork of the wheelchair robot on the stairs is analyzed. In order to obtain the stability of wheelchair robot when it climbs obstacles, centroid projection method is applied to analyze the static stability, stability margin is proposed to provide the stability under some dynamic forces, and the push rod rotation angle in terms of the guaranteed stability margin is given. Finally, the dynamic model of the wheelchair robot based on Lagrange equation is established, which can be a theoretical foundation for the wheelchair control system design.

关键词： wheelchair robot wheel/track coupling mechanism centroid projection method sta-bility margin dynamic analysis

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A Direct Swing Constraint-based Trajectory Planning Method for Underactuated Overhead Cranes

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Acta Automatica Sinica 2014年第11期40卷 2414-2419页

作者： Peng-Cheng WANG Yong-Chun FANG Zi-Ya JIANG Institute of Robotics and Automatic Information System (IRAIS) Nankai University Tianjin 300071 China Tianjin Key Laboratory of Intelligent Robotics Nankai University Tianjin 300071 China State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China

This paper proposes a novel swing constraint-based trajectory planning method for nonlinear overhead crane systems. To enhance the efficiency and security of the transportation process, some desired trajectories are designed to achieve the following merits: 1) leading the trolley to reach the destination sufficiently fast; 2) keeping the payload swing in an acceptable domain; 3) eliminating the residue swing when the trolley stops at the desired position. Specifically, the trajectories are divided into three stages. For each stage, the desired curve of the swing angle is directly constructed in accordance with anti-swing and zero-residual swing requirements, based on which the trolley trajectory is then obtained by analyzing the nonlinear kinematics of the crane system. An optimization mechanism is introduced to make intelligent compromises among the indices of transportation time, maximal swing angle, and so on. Both simulation and experimental results are provided to demonstrate the performance of the proposed direct swing constraint-based trajectory planning method.

关键词： Trajectory planning overhead cranes swing optimization nonlinear kinematics

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A coordination control strategy of voltage source converter based MTDC for offshore wind farms

A coordination control strategy of voltage source converter ...

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2014 IEEE Industry Application Society Annual Meeting, IAS 2014

作者： Ren, Jing-Guo Li, Ke-Jun Sun, Lijun Zhao, Jian-Guo Liang, Yong-Liang Lee, Wei-Jen Ding, Zhao-Hao Sun, Ying Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong University Jinan250061 China State Grid of China Technology College Jinan250002 China Energy Systems Research Center University of Texas at Arlington ArlingtonTX76019 United States Shandong Electric Power Research Institute China

ISBN: (纸本)9781479922888

This paper proposes a coordination control strategy of voltage source converter based multi-terminal DC (VSC-MTDC) transmission system for integrating large-scale offshore wind power. Using a typical five-terminal DC transmission system as an example, coordination control strategy based on local controller among converter stations is proposed. Based on the DC voltage -Active power characteristic, improved control strategy for auxiliary converter station and APC converter station are proposed respectively. Also the working mode of the two converter stations is analyzed. The basis of parameter selection of auxiliary converter station and APC converter station is presented due to DC power flow distribution and maximum and minimum operational mode. Finally, simulations in PSCAD/EMTDC are conducted to validate the multi-point DC voltage control method under various operating state in normal, master converter station fault and auxiliary converter station fault conditions respectively. Results show that this method can guarantee the active power allocation of VSC-MTDC transmission system and good control effects are obtained. © 2014 IEEE.

关键词： Offshore wind farms

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Self-balancing robust scheduling model for demand response considering electricity load uncertainty in enterprise microgrid

Self-balancing robust scheduling model for demand response c...

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IEEE General Meeting Power& Energy Society

作者： Kun Liu Feng Gao Zhaojie Wang Xiaohong Guan Qiaozhu Zhai Jiang Wu State Key Laboratory for Manufacturing System Engineering Xi'an Jiaotong University Xi’ an China Ministry of Education Key Lab for Intelligent Networks and Networks Security Xian Jiaotong University Xi’ an China

In enterprise microgrid such as steel plants, the self-generating output is not equal to the electricity load because of the electricity load uncertainty and the self-generation power plant's limits. In order to decrease the unbalance punishment cost caused by the non-equality, electricity self-balancing multi-levels model in which load uncertainty is described by a certain interval and the objective is to minimize the unbalance punishment cost and load shifting cost at the worst case is built based on the robust optimization in this paper. The multi-levels model is equivalently transformed to single level model using a set of constraints instead of the lower problem to improve the efficiency of solution. Finally, the paper tests an enterprise microgrid and the results show that proposed approach can decrease the total cost and the unbalance obviously.

关键词： Electricity Load modeling Robustness Generators Uncertainty Power systems Optimization

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Coordinated control strategy of air-conditioning loads for power system balancing

Coordinated control strategy of air-conditioning loads for p...

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International Conference on Power system Technology (POWERCON)

作者： Meng Liu Zhongkang Wei Xiaodong Chu Wen Zhang Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education (Shandong University) Jinan China State Grid Jibei Electric Power Company Beijing China

In this paper a coordinated control strategy of air-conditioning load groups is proposed to help correct imbalances between load and generation, especially when the power system is under stressed conditions such as the loss of power generation. Firstly, a decentralized air-conditioning load group control strategy (control mode 1) is presented accounting for maintenance of load diversity, so that the large oscillations of aggregated power of load group caused by diversity loss can be avoided. However, there is an unwanted parasitic "power peak" in the control mode 1. To eliminate the negative effects of the "power peak", another load control strategy (control mode 2) is borrowed from the literature which requires to communicate with the control center. Both of the control modes 1 and 2 adopt a segmental load recovery scheme to avoid "recovery peak". Then, a coordinated load control strategy is presented to coordinate the control modes 1 and 2. The "power peak" in control mode 1 is used as the power control objective for the load group of the control mode 2, and the control signal for control mode 2 can be calculated using the dichotomy method. Simulation results verify the effectiveness of the proposed coordinated control strategy of air-conditioning loads for power system balancing.

关键词： Load flow control Temperature control Power systems Load modeling Frequency control Atmospheric modeling Oscillators

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Simulation platform of monitoring and tracking micro system for dangerous chemicals transportation

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Journal of Networks 2013年第2期8卷 477-484页

作者： Hu, Haiyan Wang, Pengfei Sun, Lining School of Mechanical and Electric Engineering Soochow University Suzhou China State Key Laboratory of Robotic and System Harbin Institute of Technology Harbin China

Real test method of monitoring and tracking micro system for dangerous chemicals transportation has many disadvantages: long test cycle, high test cost, high test risk and bad reproducibility. Aimed at these disadvantages, a simulation platform which can be used for the simulation test of monitoring and tracking micro system is developed. This simulation platform is composed of motion simulator and simulation environment. The motion simulator is a kind of parallel robot with Hexaglide structure and has a total of 8 degrees of freedom (DOF). This parallel simulator cannot only realize the motion simulation of yaw, pitch and roll, but also provide pure linear motion in the Y direction, which is significant for the acceleration or deceleration simulation. The simulation environment is developed with a sealed cavity, in which a steel tank is used to simulate the tanker for dangerous chemicals transportation. The environment parameters such as temperature, humidity, concentration of combustible gas, the pressure and liquid level in tank can be measured and changed. Based on the motion simulator and the simulation environment, motion parameters such as position, attitude, angular rate, velocity and acceleration and the environment parameters can be measured simultaneously by micro system and standard sensors. With the comparison of these measured data, the micro system can be validated. This simulation platform provides a good test method for the monitoring and tracking micro system and has important significance for dangerous chemicals transportation. © 2013 ACADEMY PUBLISHER.

关键词： Chemicals

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