Table of Content

28 February 2011, Volume 45 Issue 02 Previous Issue    Next Issue

Automation Technique, Computer Technology

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Fast Approximate Clustering Algorithm and Its Application in Image Retrieval GU Wangyi,ZHU Lin,YANG Jie 2011, 45 (02):  149-0153.  Abstract ( 5497 )   Save The fast approximate Kmeans algorithm (FAKM) was proposed to solve the limitations of traditional Kmeans algorithm in the large scale database. Based on the approximate Kmeans algorithm (AKM), FAKM classifies the cluster centers according to cluster results. This new algorithm filters out the cluster centers with few samples, and makes good use of those with intensive and stable samples, and thus the number of samples and clusters will reduce in each iteration. Accordingly it can improve the speed of this algorithm and refine the cluster result. Several experimental results in image retrieval system are presented to demonstrate its average advantage over Kmeans and AKM in the clustering time, retrieval time and the robustness capability of retrieval accuracy. Related Articles | Metrics

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Image Retrieval Research on Semantic Binding Hierarchical Visual Vocabulary FU Guanglei1，SUN Tanfeng1,2，JIANG Xinghao1,2 2011, 45 (02):  154-0158.  Abstract ( 3659 )   Save This paper proposed a hierarchical semantic model which can destruct complex image semantic, and presented the method to destruct complex semantic and to construct model. Then the paper proposed the concept of semantic binding hierarchical visual vocabulary which is based on the hierarchical semantic model and also presented the method and steps to build the visual vocabulary, and the resolution to some detail problems about vocabulary as well. The paper applied the visual vocabulary into the content and semantic based image retrieval and proposed the steps to construct the image retrieving system and to retrieving images. The proposed model and method can support both the image retrieval based on image content and the image retrieval based on image semantic. The experiments prove the better performance of the model and method compared with the traditional SIFT(Scale Invariant Feature Transform) feature based image retrieval. Related Articles | Metrics

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Uncertain Milk RunBased Cross Docking Scheduling:Model and Algorithms MAI Jiaji,CHEN Feng 2011, 45 (02):  159-0163.  Abstract ( 3403 )   Save This paper studied a milk run based cross docking scheduling problem with uncertain transportation time. By describing problem formally, a mixed integer linear programming is built under uncertain situation. A twostage heuristic and a tabu search algorithm are presented. Numerical experiments under small and large scale situations are given to verify efficiencies of the proposed heuristics. Related Articles | Metrics

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A Named Entity Mining Method Based on Transfer Learning ZHAI Haijun1,2,GUO Yong3,GUO Jiafeng2,CHENG Xueqi2 2011, 45 (02):  164-0167.  Abstract ( 3300 )   Save This paper addresses the problem of mining named entities from query logs. A novel scheme was introduced based on transfer learning, which trains classifier for target category by leveraging Wikipedia data source. In this way it can greatly make use of supervised learning and also deal with the large scale labeling problem. The experiment results show the effectiveness of the novel scheme based on transfer learning. Related Articles | Metrics

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A Revised Scatter Search Algorithm for Path Planning of Multiple UAVs BAI Jie1,YANG Genke1,PAN Changchun1,SUN Kai2 2011, 45 (02):  173-0178.  Abstract ( 4054 )   Save The unmanned aerial vehicle (UAV) path planning problem in uncertain and adversarial environment is modeled as a vehicle routing problem (VRP). After that a revised hybrid algorithm based on scatter search optimization was proposed. First，with the prior surveillance and experiential evaluation, Bayes rule is used to compute the probability of threats of flight across each pair of neighboring points, and then a weighted graph can be generated based on the threat probability map in the given planning area．The original problem is transformed to be a VRP. Then, a hybrid routing algorithm is adopted to solve the VRP problem. The proposed algorithm incorporates simulated annealing (SA) method into scatter search (SS), such that it can take advantages of both the global search ability of SS and the local optimization capability of SA in order to get good paths. The proposed method can improve the quality of solutions while not incurring additional time. Finally, computational experiments were conducted to verify the method. Related Articles | Metrics

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Knowledge Acquisition Techniques of Fault Diagnosis System Based on Test Event Graph XUAN Jianqiang1，LI Qingdong1，JIANG Jiahe1，REN Zhang1，CHEN Lulu2 2011, 45 (02):  179-0183.  Abstract ( 3216 )   Save As the difficulty of knowledge acquisition restricts the application of launch vehicle fault diagnosis expert system, a knowledge acquisition method based on test event graph was proposed. By setting a reasonable graphics components, drawing out the test event graph, it can well represent the testing process of launch vehicle, then designing the algorithm that can automatically translate the test event graph into the knowledge of expert system knowledge base. This graphical method can effectively simplify the difficulty of knowledge acquisition, and is easy to understand and use. Through the testing, this method has good prospect for engineering application. Related Articles | Metrics

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Trajectory Tracking of Fully Actuated AUV Based on TLC Method GE Hui1,JING Zhongliang1，GAO Jian2 2011, 45 (02):  184-0189.  Abstract ( 3617 )   Save Trajectory linearization control(TLC) was used to design the trajectory tracking control system for the fully actuated underwater vehicle. The TLC method is a novel and effective control theory for the tracking and decoupling method for nonlinear system which is essentially robust to the outside disturbance and could adjust the bandwidth online. The whole trajectory tracking control system is divided into two loops: fast loop and slow loop based on the time scale separation idea which belongs to the differential equation singular perturbation theory. The TLC controller is designed for the two loops. Lyapunov method is used in the stability analysis. The simulation proves the availability of the TLC controllers. Related Articles | Metrics

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Sliding Mode Fault Tolerant Control for Satellite Attitude Systems Based on Sliding Mode Observer CHENG Yuehua1，2,JIANG Bin1，SUN Jun3，4,FAN Wen1 2011, 45 (02):  190-0194.  Abstract ( 3797 )   Save In the presence of actuator faults in attitude control system of satellite, a method of sliding mode fault tolerant control based on sliding mode observer was proposed. The estimation of attitude and angle rate was obtained via a sliding mode observer, and an iterative learning algorithm was utilized to update the switching gain of the sliding mode term. Considering actuator faults as unknown dynamics, a method of sliding mode fault tolerant control which is insensitive to the actuator faults of attitude control system of satellite was presented. By using the system, input and state information, unknown dynamics was estimated based on which a sliding mode control law was designed. Finally, the numerical simulation result demonstrates the effectiveness of the proposed fault tolerant control method. Related Articles | Metrics

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Analytics of Human Dynamics in Email Networks ZHENG Ziyuan，WANG Xiaofan 2011, 45 (02):  195-0201.  Abstract ( 3757 )   Save This article analyzed the email communication patterns of users reflected in a national university’s email network. It is shown that the two existed models, prioritybased queuing model and the cascading nonhomogeneous Poisson process model, both fail to describe properly the dynamic mechanism in the email network. The hypothesis in the prioritybased queuing model that users share a universal behavior pattern is unreasonable; besides the cascading nonhomogeneous Poisson process cannot embody the unexpected cessation or dynamic evolution in individual activities. Therefore, the clusteringanalysisbased segmented cascading nonhomogeneous Poisson process model is promoted which can produce better predictions. Related Articles | Metrics

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Analysis and Control Strategy of a ThreeAxis Electric Rotary Table Dynamic Coupling LI Fujun1,LUO Baoying1,ZENG Jungao2,WANG Xuyong1,TAO Jianfeng1,LIU Peng1 2011, 45 (02):  202-0207.  Abstract ( 3269 )   Save This paper built a kinematics equation and dynamics equation for a threeaxis electric rotary table from the point of view of dynamics of multibody systems, and studied the effect of the dynamic coupling. An active control strategy using velocity internal feedback for a threeaxis electric rotary table dynamic coupling was presented. This strategy need not depend on the accurate modeling of the study object and it is very easy to be accomplished. The simulation result shows that this coupling control strategy is valid and the rotary table has obtained a good position accuracy and velocity smoothness. At last the paper verifies this control strategy in the practical application and the rotary table actually obtains a good control performance using this control strategy. Related Articles | Metrics

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Modeling of Fluid Network Using EABased Parameter Identification NI Hea,b,CHENG Ganga,SUN Fengruib 2011, 45 (02):  208-0213.  Abstract ( 3952 )   Save Using evolutionary arithmetic this paper studied the modeling of thermofluid network which existed in thermopower system rifely. First, a general mathematic modeling of fluid network was established based on the basic physical laws, and then evolutionary arithmetic was adopted to identify the parameters of network. This method avoids the calculational errors of conventional methods that using experiential values or testing data, enhances the computational precision of model and makes the behaviors of model accordant to the real object. This method was used to simulate the steam network in a certain type marine power plant, and the outputs of model against the real values were measured. The results show that the parameters identified model has preferable accuracy, and the EAbased modeling method is useful. Related Articles | Metrics

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Violent Videos Classification Algorithm Based on Bag of Audio Words LI Rongjie1,JIANG Xinghao1,2,SUN Tanfeng1,2 2011, 45 (02):  214-0218.  Abstract ( 4006 )   Save A new method to classify the violent videos by the bag of audio words was introduced. The MPEG7 audio descriptors are firstly extracted, including the low level features such as AudioSpectrumCentroid and AudioSpectrumSpread etc. After that, the audio words are built through the MPEG7 high level descriptor, the AudioSighnature, which is considered as the fingerprint of the audio stream. The support vector machine is used to classify the feature vectors into two genres, which are the violent and nonviolent. There are three experiments in this paper: the research on the different types of the audio words, the different size of words and the classification of the shots detected from the visual features. It is demonstrated from the experiment result that the proposed method achieves good recall accuracy. Related Articles | Metrics

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Dynamic Mathematics Model of a Kind of 3 DOF Parallel Platform Based on Pneumatic Artificial Muscles SHEN Wei,SHI Guanglin 2011, 45 (02):  219-0224.  Abstract ( 3392 )   Save In terms of a pneumatic artificial muscle parallel platform, a new mathematic model of pneumatic artificial muscle was introduced to derive the state space 3 DOF mathematics model. In 3 DOF PID position tracking control experiments, the corresponding physic parameters data were collected. The inner air pressure data collected in the experiment are taken as the input to simulation dynamic models. The comparative study of simulations and experiments suggests the rationality and validity of the dynamic model. Related Articles | Metrics

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Action Recognition Based on Video Words with a SpaceTime Speeded up Robust Features Descriptor FENG Bing1，JIANG Xinghao1,2，SUN Tanfeng1,2 2011, 45 (02):  225-0229.  Abstract ( 3574 )   Save A novel spacetime speeded up robust features (SURF) descriptor and its application to human action recognition by combining with a bag of video words approach were presented. The new descriptor can better represent the spatiotemporal nature of the video data in the application of action recognition. A bag of words approach is used to represent videos, and a soft weighting strategy is exploited. Experiment is done in the KTH’s action recognition dataset. In the experiment a voting system containing second pass prediction is employed in classifying actions as well as the traditional classification framework. The results of experiment show this approach is able to outperform the previously proposed schema both in speed and accuracy, while the new voting schema works better than the traditional one in some actions. Related Articles | Metrics

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Immobility Analysis Based on 2ndorder Contact Model LUO Chen,ZHU Limin,DING Han 2011, 45 (02):  230-0235.  Abstract ( 3151 )   Save Based on the signed distance function from point to surface, this paper defined the signed distance function from surface to surface, analyzed the first and second differential properties and derived its 2nd Taylor expansion. Then by using the theories of signed distance function, 1st and 2nd free motions were presented in order to describe rigid body B motion with respect to multiplefinger A1,A2,…Ak and the 1st and 2nd free motion have the feature of coordinate invariance. Based on the 1st and 2nd free motion, a new method was presented to analyze the immobility of multiplefinger grasps. Lastly, the simulation result of four fingers’ immobile grasp at a tetrahedral shows the validity of the method. Related Articles | Metrics

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Local Extreme Learning Machine and Its Application to Condition Online Monitoring ZHANG Xian,WANG Hongli 2011, 45 (02):  236-0240.  Abstract ( 10961 )   Save To reduce the computational cost of extreme learning machine (ELM) online training, a new algorithm called local extreme learning machine (LELM) was proposed. LELM adopts the latest training sample and abandons the oldest training sample iteratively to insure that only the most relevant samples are applied to LELM online training. The output weights of LELM are determined recursively during each training procedure to reduce the computational cost of online training. The numerical experiments on chaotic time series prediction indicate that the online training computational cost of LELM is much less than that of ELM. The numerical experiments on radar transmitter condition online monitoring based on time series prediction indicate that LELM has better performance in online training computational cost and prediction accuracy in comparison with conventional electronic system condition online monitoring method using adaptive grey model. Related Articles | Metrics

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Robust Fault Detection Observer Design for Nonlinear Distributed Parameter Systems LIU Pingyue，WU Huaining 2011, 45 (02):  241-0246.  Abstract ( 4013 )   Save This paper addresses the problem of robust fault detection observer (FDO) design for a class of nonlinear distributed parameter systems described by partial differential equations (PDEs). Firstly, applying modal decomposition techniques, the PDE system can be transformed to an equivalent infinitedimensional ordinary differential equations (ODE) system. Based on the spectrum of spatial differential operator, the ODE system can be represented by a finitedimensional slow subsystem and a coupled infinitedimensional fast subsystem. Subsequently, a finitedimensional FDO is designed based on the slow subsystem such that the normal residual system is asymptotically stable for all admissible unknown nonlinear dynamics and fast subsystem dynamics. Then, the corresponding timevarying threshold is proposed to implement fault detection. Finally, numerical simulations are performed to demonstrate the effectiveness of the developed FDO design methodology. Related Articles | Metrics

Physics

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State Variable Method for Transient Heat Conduction Analysis of Composite Sold Cylinder SHENG Hongyu 1, LI Heping 1，YE Jianqiao 2,WU Xutao 1 2011, 45 (02):  247-0251.  Abstract ( 4432 )   Save The state space theory was introduced and a difference scheme in time domain was applied to establish the state equation of solid cylinder for the analysis of transient heat conduction. In order to check the effectiveness of the present approach, an exact solution for a given initial temperature distribution was provided and the results were compared with that of the present method. The numerical results illustrate that the present approach has high solving precision and is very effective for the transient analysis of heat conducting process of cylindrical shell. Furthermore, the present method can be extended to the analysis of transient coupling thermal stress of composite laminated cylindrical shell. Related Articles | Metrics

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Investigation on Radial Composite Round Tube Piezoelectric Ceramic Ultrasonic Transducer LIU Shiqing1,YAO Ye2 2011, 45 (02):  252-0256.  Abstract ( 3232 )   Save The radial vibration of a radial composite round tube piezoelectric ultrasonic transducer was studied. The transducer consists of an inner radially polarized short piezoelectric ceramic round tube and an outer short thinwalled metal prestressed tubular shell which are compounded in the radial direction. Based on the elastic dynamics theory and the electromechanical analogy, the equivalent circuit of the radial composite piezoelectric transducer is derived. The analysis formulae of the resonance frequency and the antiresonance frequency equation as well as the effective electromechanical couple coefficient of the transducer are obtained. By testing the radial resonance frequencies and the effective electromechanical couple coefficients of some trialmade transducers,it is shown that the theoretical radial resonance frequencies of the transducers from the frequency equation in this paper are in a good agreement with the measured results. Related Articles | Metrics

Aeronautics & Astronautics

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Air Combat DecisionMaking for Multifighter Coordinated Attack Based on Probability Collectives LIU Bo,CHEN Shaodong,HE Jianliang 2011, 45 (02):  257-0261.  Abstract ( 4009 )   Save A new algorithm based on probability collectives was proposed to solve the decisionmaking of multifighter to coordinated attack multitarget without centric control. Firstly, the coordinated distributed decision making model is proposed based on missile which is defined as an agent. To solve an optimization problem in which there is subspace full of local optimal value near the global optimum in the solution space, the new algorithm turns it into a convex problem in a space of probability distributions based on probability collectives. Secondly, the probability collectives framework is extended by agent contribution rate to realize accurate convergence. The simulation results show that as compared with conventional methods, the proposed method is able to converge to the global optimum with more stability, scalability and faster convergence rate. Related Articles | Metrics

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Reentry Trajectory Optimization of Hypersonic Vehicle Based on Pseudo Energy SUN Yong，DUAN Guangren，ZHANG Maorui，ZHANG Ze 2011, 45 (02):  262-0266.  Abstract ( 3355 )   Save The whole heating of the hypersonic vehicle in reentry process was minimized based on the pseudo energy, which is used to divide the reentry trajectory into some segments. The control variable parameterization with different time durations was introduced to optimize each trajectory. The reentry trajectory of the hypersonic vehicle must satisfy the heating rate, dynamic pressure and the overload path constraints. The control variable parameterization was applied and the trajectory optimization problem become a nonlinear programming problem by the time scaling and the inequality constraint transformation. The pseudo energy definition was introduced to divide the reentry trajectory into some segments for optimization. A case with four segments was taken as an example for simulation. The computing time is less than that of one segment by 50%. Related Articles | Metrics

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Task Planning Method for Multipayload Remote Sensing UAV CAI Zhihao，YAN Ruyi，WANG Yingxun 2011, 45 (02):  267-0271.  Abstract ( 4090 )   Save In view of the remote sensing of UAV (unmanned aircraft vehicle) which carries multiple payloads, a task planning method was studied to get more useable results. According to payloads’ different requirements on flight altitude, flight speed and so on, the task planning method commonly includes route planning and payloads planning. The method based on XML (eXtensible Markup Language) modeling remote sensing can develop universal standards for task planning norms, improve the UAV remote sensing flight efficiency and adaptability. Using KML (Keyhole Markup Language) to demonstrate the planning results on Google Earth, real time planning results can be visually displayed on GISbased user interface and obtain effective assessments. Related Articles | Metrics

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Modeling and Disturbance Observer Based Control for a Hypersonic Vehicle QU Xin,REN Zhang,SONG Jianshuang,WANG Junbo 2011, 45 (02):  272-0276.  Abstract ( 4148 )   Save The disturbance observer based control was proposed for a hypersonic vehicle controller design. Hypersonic vehicles were typically characterized by a significant degree of interaction between the highly elastic airframe and the propulsion system. A nonlinear longitudinal dynamic model considering flexible effects and the coupling between the aerodynamics and propulsion systems was established. Then, the potential sources of uncertainty for this class of vehicle were discussed and three forms of uncertainty models were developed: real parameter, unstructured, and structured. The disturbance observer based control law was designed to improve the performance and robustness for nonlinear model. Finally, the simulation results show that the proposed method is feasible. Related Articles | Metrics

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Hierarchical Hybrid Reliability Modeling Method for Flight Control Computer System SUN Xiaozhe，LI Weiqi，CHEN Zongji 2011, 45 (02):  277-0283.  Abstract ( 3543 )   Save According to the characteristics of complex dissimilar, redundant flight control computer system and the combination of the advantage of static and dynamic reliability modeling, the hierarchical hybrid reliability modeling method(HHRM), which combines reliability block diagram(RBD) and generalized stochastic Petri net(GSPN), was presented. In the case that components of common cause failures exist in the various lowlevel subsystems, the system reliability modeling method was analyzed. The HHRM and GSPN methods were respectively used for the reliability modeling and analysis of the main flybywire flight control computer system of Boeing777. Compared with the dynamic GSPN method, the HHRM method adopted static and dynamic reliability modeling methods and combined the flexibility of statespace models and efficiency of combinatorial models. The state space explosion problem caused by GSPN method is avoided by using hierarchical structure. The results of the two methods show that the HHRM method is feasible, efficient and accurate. Related Articles | Metrics

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Robust Model Following Switching Control of BTT Missile CHI Xueqiana,WANG Qinga，HOU Yanzea,DONG Chaoyangb 2011, 45 (02):  284-0289.  Abstract ( 3443 )   Save The mixed pitchyaw channel dynamic model of banktoturn (BTT) missile at one operating point was described as a linear switched system switched as the roll angle rate changes. The reference model and control law of each subsystem were designed based on the eigenstructure assignment method and the feedforward method. The different controllers can be fast switched according to the switching law determined by the roll angle rate of missile. Thus the set of different controllers can restrain the model uncertainties caused by the rapid change of roll angle rate, which means it has better robustness. To ensure the uniform boundedness of the closedloop switched system within the whole varying range of roll angle rate, a sufficient condition in the form of linear matrix inequations was deduced using the common Lyapunov function method. Related Articles | Metrics

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Semantic Interoperability Based on Domain Ontology for MultiUAVs WU Jiang，CHEN Zongji 2011, 45 (02):  290-0294.  Abstract ( 3264 )   Save The formal modeling method for UAVs（unmanned air vehicles） interoperability based on domain ontology semantic model was introduced. Semantic description model for multiUAVs interaction description and the semantic enhanced method for interactive configuration were proposed. UAV ontology and UAV interaction description ontology were designed. Based on the OWLS (ontology Web language for services), dynamic properties description of multiUAVs was extended, which can provide semantic description for service quality, service status and service relationships, etc. In order to achieve multiUAVs’ automatic and dynamic configuration, semantic method based on domain ontology was used to configuration management. Highlevel semantic matching was introduced in multiUAVs configuration, which can increase multiUAVs’ interaction configuration with semantic processing. The simulation and experimental result shows that the proposed method of semantic interoperability based on ontology can support multiUAVs effectively in future. Related Articles | Metrics

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Fuzzy Sliding Mode Control for Hypersonic Reentry Vehicles LI Jingjing,REN Zhang，SONG Jianshuang 2011, 45 (02):  295-0300.  Abstract ( 3282 )   Save This paper developed a fuzzy sliding mode controller for the attitude control of hypersonic reentry vehicles. First, the controloriented model of vehicles is given. Then, by combining fuzzy control theory and sliding mode control technique, a fuzzy sliding mode control method is proposed. The design of fuzzy sliding mode controller is based on a predesigned sliding surface in the stable error phase plane. The output of the fuzzy controller is accordingly adjusted with respect to the distances between the error state and the sliding surface, which could force the system state to reach the sliding surface, in turn lead error to converge to the origin along it. Furthermore, this control design method is applied to the attitude control problem of hypersonic reentry vehicles. Three independent fuzzy sliding mode controllers are designed for the control of angle of attack, sideslip and bank. In addition, a practical piecewise linear control allocation scheme is introduced. Finally, the simulation results show that the proposed method is feasible. Related Articles | Metrics