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QoS multicast routing scheme using QGA in IP/DWDM networks

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 95-100页

作者： XING Huan-lai bai Lin JI yue-feng Key Laboratory of Optical Communications and Lightwave Techno ogies Beijing University of Posts and Telecommunications Beijing 100876 China

This article studies multi-constraints least-cost multicast routing problem in internet protocol over dense wavelength division multiplexing （IP/DWDM） networks. To address this problem, an individual-difference-based quantum genetic algorithm （IDQGA） is proposed. This algorithm considers individual differences among chromosomes by introducing an adaptive rotation angle step determination scheme and a grouping-based quantum mutation operation. Simulations are conducted over network topologies. The results indicate that compared with other heuristic algorithms, IDQGA has better optimal performance on solving quality of service （QoS） multicast routing problem in IP/DWDM networks and is characterized by strong robustness, high success ratio and excellent capability on global searching.

关键词： IP-over-DWDM multicast QoS quantum genetic algorithm

Soil Fertility Self-development Under Ecological Restoration in the Zhuxi Watershed in the Red Soil Hilly Region of China

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Journal of Mountain Science 2014年第5期11卷 1231-1241页

作者： bai Li-yue CHEN Zhi-qiang CHEN Zhi-biao College of Geographical Sciences Fujian Normal University Institute of Agriculture Regional Planning of Fujian Province

Current methods that utilize simple data or models to judge whether soil fertility can selfdevelop are not sufficiently rigorous. A new framework has been set up using catastrophe theory, laboratory experiment, field work, and 3S(Geographic information system, Global positioning system, and Remote sensing) to explore soil fertility catastrophe under ecological restoration, discriminate whether soil fertility can self-develop, and propose adjustment of ecological restoration measures in the Zhuxi watershed of Changting County, Fujian Province, China, which is a typical representative of the red soil hilly region of China. The results show that: 1) the soil fertility is obviously improved through the four ecological restoration measures, which impels soil fertility catastrophe. Among 89 soil samples, catastrophic soil samples and stable soil samples account for 26(29.21%) and 63(70.79%) of the samples, respectively. The four ecological restoration measures are listed in the order lowquality forest improvement > arbor–bush–herb mixed plantation > orchard improvement > closing measures according to the proportions of catastrophic soil samples. A typical soil sample in Bashilihe that can self-develop is selected as the criterion to judge the upper lobe and lower lobe of soil fertility in the process surface of the Cusp catastrophe model. Twenty-six(29.21%) were in the middle lobe, 10(11.24%) were in the upper lobe, and 53(70.79%) were in the lower lobe. The catastrophic direction of 26 catastrophic soil samples is to the upper lobe according to soil and water loss change as well as fieldwork. There is a significant positive correlation of Δ with soil and water loss change, and the lower soil and water loss relates to higher catastrophic probability. 2) Soil fertility self-development could be regionalized as "Soil fertility can self-develop" whose area was 12.74 km2(28.33%) distributed mainly in the leftmost and rightmost parts, "Soil fertility tends to self-develop" who

关键词： Soil fertility Catastrophe Ecological restoration Red soil hilly region

An efficient stiffness analysis model based on shear deformation theory for flexible skin shear variable-sweep wing

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Chinese Journal of Aeronautics 2024年第10期37卷 445-458页

作者： yue bai Guang YANG Hong XIAO Hongwei GUO Rongqiang LIU Bei LIU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China China Aerodynamics Research and Development Center Institute of High-Speed AerodynamicsMianyang 621000China

Fixed-wing aircraft cannot maintain optimal aerodynamic performance at different flight speeds. As a type of morphing aircraft, the shear variable-sweep wing(SVSW) can dramatically improve its aerodynamic performance by altering its shape to adapt to various flight *** order to achieve smooth continuous shear deformation, SVSW's skin adopts a flexible composite skin design instead of traditional aluminum alloy materials. However, this also brings about the non-linear difficulty in stiffness modeling and calculation. In this research, a new SVSW design and efficient stiffness modeling method are proposed. Based on shear deformation theory, the flexible composite skin is equivalently modeled as diagonally arranged nonlinear springs, simulating the elastic force interaction between the skin and the mechanism. By shear loading tests of flexible composite skin, the accuracy of this flexible composite skin modeling method is verified. The SVSW stiffness model was established, and its accuracy was verified through static loading tests. The effects of root connection, sweep angles, and flexible composite skin on the SVSW stiffness are analyzed. Finally, considering three typical flight conditions of SVSW: low-speed flow(Ma = 0.3,Re = 5.82 × 10^(6)), transonic flow(Ma = 0.9, Re = 3.44 × 10^(6)), and supersonic flow(Ma = 3,Re = 7.51 × 10^(6)), the stiffness characteristics of SVSW under flight conditions were *** calculated results guide the application of SVSW.

关键词： Shear variable-sweep wing(SVSW) Flexible composite skin Morphing mechanism Stiffness analysis Loading tests Structure

Gain adaptive sliding mode controller based on interval type-Ⅱfuzzy neural network designed for attitude control for micro aircraft vehicle

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International Journal of Intelligent Computing and Cybernetics 2014年第2期7卷 209-226页

作者： Xiangjian Chen Di Li Zhijun Xu yue bai School of Computer Science and Engineering Jiangsu University of Science and TechnologyZhenjiangJiangsuChina The 723 Institute of China Shipbuilding Industry Corporation(CSIC) YangzhouJiangsuChina Chang Chun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchunChina

Purpose–Micro aerial vehicle is nonlinear plant;it is difficult to obtain stable control for MAV attitude due to *** purpose of this paper is to propose one robust stable control strategy for MAV to accommodate system uncertainties,variations,and external ***/methodology/approach–First,by employing interval type-II fuzzy neural network(ITIIFNN)to approximate the nonlinearity function and uncertainty functions in the attitude angle dynamic model of micro aircraft vehicle(MAV).Then,the Lyapunov stability theorem is used to testify the asymptotic stability of the closed-loop system,the parameters of the ITIIFNN and gain of sliding mode control can be tuned on-line by adaptive laws based on Lyapunov synthesis approach,and the Lyapunov stability theorem has been used to testify the asymptotic stability of the closed-loop ***–The validity of the proposed control method has been verified through real-time *** experimental results show that the performance of interval type-II fuzzy neural network based gain adaptive sliding mode controller(GASMC-ITIIFNN)is significantly improved compared with conventional adaptive sliding mode controller(CASMC),type-I fuzzy neural network based sliding mode controller(GASMC-TIFNN).Practical implications–This approach has been used in one MAV,the controller works well,and which could guarantee the MAV control system with good performances under uncertainties,variations,and external ***/value–The main original contributions of this paper are:the proposed control scheme makes full use of the nominal model of the MAV attitude control model;the overall closed-loop control system is globally stable demonstrated by Lyapunov stable theory;the tracking error can be asymptotically attenuated to a desired small level around zero by appropriate chosen parameters and learning rates;and the MAV attitude control system based on GASMC-ITIIFNN controller can achieve favourable tracki

关键词： Flight control Performance Intelligent control Micro aircraft vehicle Attitude stabilization High pointing accuracy

SAMES： deadline-constraint scheduling in MapReduce

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Frontiers of Computer Science 2015年第1期9卷 128-141页

作者： Xite WANG Derong SHEN Mei bai Tiezheng NIE yue KOU Ge YU College of Information Science & Engineering Northeastern University Shenyang 110819 China

MapReduce is a popular parallel data-processing system, and task scheduling is one of the kernel techniques in MapReduce. In many applications, users have requirements that their MapReduce jobs should be completed before specific deadlines. Hence, in this paper, a novel scheduling algorithm based on the most effective sequence （SAMES） is proposed for deadline-constraint jobs in MapReduce. First, according to the characteristics of MapReduce, we propose a novel sequence-based execution strategy for MapReduce jobs and a new concept, the effective sequence （ES）. Then, we design some efficient approaches for finding ESes and choose the most effective sequence （MES） for job execution. We also propose methods for MES-updates and exception handling. Finally, we verify the effectiveness of SAMES through experiments. The experimental results show that SAMES is an efficient scheduling algorithm for deadline-constraint jobs in MapReduce.

关键词： MapReduce scheduling deadline

Attitude estimation method based on extended Kalman filter algorithm with 22 dimensional state vector for low-cost agricultural UAV

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High Technology Letters 2020年第2期26卷 125-135页

作者： Wu Helong Pei Xinbiao Li Jihui Gao Huibin bai yue Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

To overcome the shortcomings of traditional artificial spraying pesticides and make more efficient prevention of diseases and pests,a coaxial sixteen-rotor unmanned aerial vehicle(UAV)with pesticide spraying system is *** coaxial sixteen-rotor UAV’s basic structure and attitude estimation method are *** whole system weights 25 kg,cruising speed can reach 15 m/s,and the flight time is more than 20 *** the UAV takes large load,the traditional extended Kalman filter(EKF)attitude estimation method can not meet the work requirements under the condition of strong vibration,the attitude measure accuracy is poor and the attitude angle divergence is easily *** an attitude estimation method based on EKF algorithm with 22 dimensional state vector is proposed which can solve these *** UAV system consists of STM32F429 as controller,integrating following measure sensors:accelerometer and gyroscope MPU6000,magnetometer LSM303D,GPS NEO-M8N and *** attitude unit quaternion,velocity,position,earth magnetic field,biases error of gyroscope,accelerometer and magnetometer are introduced as the inertial navigation systems(INS)state vector,while magnetometer,global positioning system(GPS)and barometer are introduced as observation vector,thus making the estimate of the navigation information more *** control strategy of coaxial sixteen-rotor UAV is based on the control method of combining active disturbance rejection control(ADRC)and proportion integral derivative(PID)*** flight data are used to verify the algorithm,and the static experiment shows that the precision of roll angle and pitch angle of the algorithm are±0.1°,the precision of yaw angle is±0.2°.The attitude angle output of MTi sensor is used as *** dynamic experiment shows that the accuracy of attitude estimated by EKF algorithm is quite similar to that of MTi’s output,moreover,the algorithm has good real-time performance which meets the need of hi

关键词： coaxial sixteen-rotor unmanned aerial vehicle(UAV) extended Kalman filter(EKF) quaternion low-cost

Modeling and robust adaptive control for a coaxial twelve-rotor UAV

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High Technology Letters 2019年第2期25卷 137-143页

作者： Pei Xinbiao Peng Cheng bai yue Wu Helong Ma Ping Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033P.R.China University of Chinese Academy of Sciences Beijing 100039P.R.China

Compared with the quad-rotor unmanned aerial vehicle (UAV), the coaxial twelve-rotor UAV has stronger load carrying capacity, higher driving ability and stronger damage resistance. This paper focuses on its robust adaptive control. First, a mathematical model of a coaxial twelve-rotor is established. Aiming at the problem of model uncertainty and external disturbance of the coaxial twelve-rotor UAV, the attitude controller is innovatively adopted with the combination of a backstepping sliding mode controller (BSMC) and an adaptive radial basis function neural network (RBFNN). The BSMC combines the advantages of backstepping control and sliding mode control, which has a simple design process and strong robustness. The RBFNN as an uncertain observer, can effectively estimate the total uncertainty. Then the stability of the twelve-rotor UAV control system is proved by Lyapunov stability theorem. Finally, it is proved that the robust adaptive control strategy presented in this paper can overcome model uncertainty and external disturbance effectively through numerical simulation and prototype of twelve-rotor UAV tests.

关键词： coaxial twelve-rotor unmanned aerial vehicle(UAV) backstepping sliding mode controller(BSMC) adaptive radial basis function neural network(RBFNN) external disturbances

Backstepping sliding mode tracking control of quad-rotor under input saturation

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International Journal of Intelligent Computing and Cybernetics 2012年第4期5卷 515-532页

作者： Xun Gong yue bai Zhicheng Hou Changjun Zhao Yantao Tian Qiang Sun School of Telecommunication Engineering Jilin UniversityChangchunChina Chang Chun Institute of Optics Fine Mechanics and Physics Chinese Academy of SciencesChangchunChina

Purpose–The quad-rotor is an under-actuation,strong coupled nonlinear system with parameters uncertainty,unmodeled disturbance and drive capability *** purpose of the paper is to design a flight control system to regulate the aircraft track the desired trajectory and keep the attitude angles stable on account of these ***/methodology/approach–Considering the dynamics of a quad-rotor,the closed-loop flight control system is divided into two nested loops:the translational outer-loop and the attitude *** the outer-loop,the translational controller,which exports the desired attitude angles to the inner-loop,is designed based on bounded control *** consideration of the influence of uncertain rotational inertia and external disturbance,the backstepping sliding mode approach with adaptive gains is used in the *** switching control strategy based on the sign functions of sliding surface is introduced into the design procedure with respect to the input ***–The validity of the proposed flight control system was verified through numerical simulation and prototype flight experiment in this ***,with relation to the flying,the motor speed is kept in the predetermined ***/value–This article introduces a new flight control system designed for a quad-rotor.

关键词： Quad-rotor Double-loops Backstepping algorithm Adaptive approximation Bounded control Prototype experiment Genetic algorithms Flight control

Determination of Li+ solid diffusion coefficient in LiMn2O4 by CITT

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Journal of Central South University of Technology 2005年第z1期12卷 1-4页

作者： TANG Xin-cun HUANG bai-yun HE yue-hui School of Chemistry and Chemical Engineering Central South University Changsha 410083 China State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

The capacity intermittent titration technique (CITT) was developed based on the ratio of potentio-charge capacity to galvano-charge capacity (RPG) method, to continuously determine the solid diffusion coefficient (D) of the intercalary species within insertion-host materials with a small voltage region. The linear equations of D vs the value of ratio of the potentio-charge capacity to the galvano-charge capacity (q) were given. By the CITT technique,the Li+ solid diffusion coefficients within LiMn2 O4 at different voltages were determined. The results show that the values of D varied from 3. 447× 10-9 to 7.60× 10-11 cm2/s in the voltage range of charge from 3.3 to 4.3 V as a function of voltage with "W" shape.

关键词： capacity titration technique Li+ solid diffusion coefficient LiMn2O4