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Spatial Distribution of Land Cover and Vegetation Activity along Topographic Gradient in an Arid River Valley, SW China

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Journal of Mountain Science 2009年第3期6卷 274-285页

作者： LIU Wen XU Xianli LUO Jiancheng SHEN Zhanfeng ZHONG Qiuhai Department of Automatic Control School of Automation Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China Centre for Hydrology Micrometeorology and Climate Change Department of Civil and Environmental Engineering University College Cork Cork Ireland

Anthropogenic activities have become more and more important in characterizing the landscape, but their impacts are still restricted by natural environments. This paper discusses the interactions of anthropogenic activity, vegetation activity and topography through describing the spatial distribution of land cover and vegetation activity (represented by Normalized Difference Vegetation Index, NDVI) along topographic gradient in a mountainous area of southwestern China. Our results indicate that the existing landscape pattern is controlled by anthropogenic activities as well as topographic factors. Intensive anthropogenic activities mainly occur in areas with relatively low elevation, gentle and concave slopes, as these areas are easy and convenient to attain for human. Because of the destruction by human, some land cover types (mainly grassland and shrub) are only found in relatively harsher environments. This study also finds that topographic wetness index (W) used in other places only reflects runoff generation capacity, but not indicate the real spatial pattern of soil water content in this area. The relationships between NDVI and W, and NDVI and length slope factor (LSF) show that runoff and erosion have complex effects on vegetation activity. Greater values of W and LSF will lead to stronger capacity to produce runoff and transport sediment, and thereby increase soil water content and soil deposition, whereas beyond a certain threshold runoff and erosion are so strong that they would destruct vegetation growth. This study provides information needed to successfully restore native vegetation, improve land management, and promote sustainable development in mountainous areas, especially for developing regions.

关键词： Vertical distribution of land cover Anthropogenic activity Vegetation activity Environmental variability China

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An adaptive weight PSO for rolling schedules multi-objective optimization of tandem cold rolling

An adaptive weight PSO for rolling schedules multi-objective...

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IEEE International Conference on automation and Logistics

作者： Yu Wang Yong Li Jianchang Liu Key Laboratory of Integrated Automation of Process Industry Ministry of Education Northeastern University Shenyang Liaoning China Department of Automatic Control Shenyang Institute of Aeronautical Engineering Shenyang Liaoning China

In this paper, an adaptive weight particle swarm optimization is proposed for multi-objective optimization. And it is applied to rolling schedules multi-objective optimization of tandem cold rolling. According to the demands of actual rolling schedules designing, power distribution, rolling energy consumption and slip rate are selected as objective functions. Then the multi-objective model of rolling schedules is established. The proposed algorithm is applied to rolling schedules optimization of tandem cold rolling. The result shows that the proposed method decreases the values of three objective functions simultaneously compared to actual rolling schedules. Furthermore the proposed algorithm has faster convergence speed than the adaptive weight approach GA.

关键词： Job shop scheduling Particle swarm optimization Optimization methods Power distribution Scheduling algorithm automation Energy consumption Logistics Laboratories Convergence

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Real time optimisation for thermal processes

Real time optimisation for thermal processes

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European control Conference (ECC)

作者： Míriam R. García Carlos Vilas Eva Balsa-Canto Antonio A. Alonso NUIM Hamilton Institute Ireland Facult Polytechnique de Mons Automatic Control Laboratory Belgium IIM-CSIC Process Engineering Group Vigo Spain

This work presents the theoretical design and the experimental validation of a real time optimisation logic for distributed parameter systems. This logic consists of a hierarchy of two layers. The upper layer is responsible of obtaining the optimal control profile by a suitable combination of the control vector parameterisation approach with a hybrid global-local optimiser and the use of reduced models for distributed parameter systems. The lower layer corresponds to a PID controller designed in the framework of Internal Model control to keep tracking capabilities at short time scales. This logic was applied to the real time optimisation of the thermal processing of packaged foods in batch retorts at the pilot plant available at the IIM-CSIC. The objective was to maximise food product quality while satisfying safety constraints. The proposed scheme was able to optimally operate the system under standard plant perturbations and under a pressure drop.

关键词： Optimization Real-time systems Mathematical model Valves Read only memory Heating Vectors

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Particle Swarm Optimization in Solving Vehicle Routing Problem

Particle Swarm Optimization in Solving Vehicle Routing Probl...

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International Conference on Intelligent Computation Technology and automation, ICICTA

作者： Hai Shen Yunlong Zhu Ting Liu Li Jin College of Physics Science and Technology Shenyang Normal University Shenyang China Key Laboratory of Industrial Informatics Shenyang Institute of Automation Chinese Academy and Sciences Shenyang China Key Laboratory of Industrial Informatics Shenyang Institute of Automation Chinese Academy and Sciences Beijing China Department of Automatic Control School of Information Science and Engineering Northeastern University Shenyang China Chinese Academy of Sciences Beijing Beijing CN

The vehicle routing problem (VRP) is a NP complete problem and is also a hot topic in the operational research. But traditional methods might suffer from slow convergence and the curse of large sizes, heuristics-based swarm intelligence can be an efficient alternative. Particle swarm optimization (PSO) is known to effectively solve engineering optimization problems. In this paper, the PSO in solving VRP is comprehensive surveyed from two basic aspects: the improved PSO algorithms and the particle encoding method. For each application, technical details that are required are all discussed. Finally, a summary is given together with suggestions for future research.

关键词： Particle swarm optimization Vehicles Routing automation Encoding Laboratories Computer industry Industrial control Informatics Educational institutions

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A unified approach to fuzzy modelling and robust synchronization of different hyperchaotic systems

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Chinese Physics B 2008年第11期17卷 4056-4066页

作者： Zhang, Hua-Guang Zhao, Yan Yu, Wen Yang, Dong-Sheng School of Information Science and Engineering Northeastern University Shenyang 110004 China Key Laboratory of Integrated Automation of Process Industry Ministry of Education Northeastern University Shenyang 110004 China Department of Automatic Control Engineering Shenyang Institute of Engineering Shenyang 110136 China Departamento de Control Automatico CINVESTAV-IPN Av. IPN 2508 México D. F. 07360 Mexico

In this paper, a Takagi-Sugeno (T-S) fuzzy model-based method is proposed to deal with the problem of synchronization of two identical or different hyperchaotic systems. The T-S fuzzy models with a small number of fuzzy IF-THEN rules are employed to represent many typical hyperchaotic systems exactly. The benefit of employing the T-S fuzzy models lies in mathematical simplicity of analysis. Based on the T-S fuzzy hyperchaotic models, two fuzzy controllers are designed via parallel distributed compensation (PDC) and exact linearization (EL) techniques to synchronize two identical hyperchaotic systems with uncertain parameters and two different hyperchaotic systems, respectively. The sufficient conditions for the robust synchronization of two identical hyperchaotic systems with uncertain parameters and the asymptotic synchronization of two different hyperchaotic systems are derived by applying the Lyapunov stability theory. This method is a universal one of synchronizing two identical or different hyperchaotic systems. Numerical examples are given to demonstrate the validity of the proposed fuzzy model and hyperchaotic synchronization scheme. © 2008 Chin. Phys. Soc. and IOP Publishing Ltd.

关键词： Synchronization

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Numerical simulation of flow field in a quench oil tower

Numerical simulation of flow field in a quench oil tower

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2007 ASME Pressure Vessels and Piping Conference, PVP 2007

作者： Shuihua, Zheng Shengchang, Zhang Zengliang, Gao Zhejiang University of Technology Institute of Process Equipment and Control Engineering MOE Key Laboratory of Mechanical Manufacture and Automation Hangzhou 310032 China

ISBN: (纸本)0791842819

Towers are applied in the wide range of the petrochemical industry. The flow condition and the temperature distribution in the tower are the focus of the people's attention, which would affect function of the tower and could result in unstable operation of the tower. In this paper, the flow field in a quench oil tower is simulated based on CFD method. The DPM (Discrete Phase Model) is used to calculate and analyze flow distribution and heat transfer between gas and liquid. The numerical results such as temperature and velocity distributions below lower tray in tower are obtained. According to CFD results, modification method of improving the flow distribution is proposed. Copyright © 2007 by ASME.

关键词： Flow fields

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Research on the vibratory stress relief used to reduce residual stress of mismatch butt welds of a cylinder

Research on the vibratory stress relief used to reduce resid...

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2007 ASME Pressure Vessels and Piping Conference, PVP 2007

作者： Xin, Ren Yuan, Tian Zengliang, Gao Kangda, Zhang Zhejiang University of Technology Institute of Process Equipment and Control Engineering MOE Key Laboratory of Mechanical Manufacture and Automation Hangzhou 310032 China

ISBN: (纸本)0791842843

The residual stresses of mismatch butt welds of a cylinder were measured by the blind-hole method before and after a vibratory residual stress relief treatment. The results show that this treatment could greatly reduce the maximal butt weld residual stress of dissimilar steel from 540MPa to 119MPa. The concentrated distributions of the first and the second principal residual stresses became gentle after the vibratory residual stress relief treatment. Copyright © 2007 by ASME.

关键词： Stress analysis

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Model Adjustment and Multi-Model Based Fault Diagnosis for Hydraulic Servo Axis

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IFAC Proceedings Volumes 2008年第2期41卷 13809-13814页

作者： Marco Muenchhof Mark Beck Technische Universitaet Darmstadt Institute of Automatic Control Laboratory for Control Systems and Process Automation Darmstadt Germany (Tel: +49-6151-16-3114 Technische Universitaet Darmstadt Institute of Automatic Control Laboratory for Control Systems and Process Automation Darmstadt Germany (Tel: +49-6151-16-2314

This paper presents a model adjustment and a multi-model based fault diagnosis approach. Both methods are based on the same idea. A physical model of the process is altered such that it mimics the behavior of the process in the presence of certain faults. A number of these modified models, each governing a different fault condition, are evaluated and the model with the smallest output error is determined. As this model is assumed to best govern the current process dynamics, it can be used to diagnose the actual state of the process. Two variations of this idea are presented, tailored specifically to online and offline operation respectively. For online applications, multiple models with fixed parameters are evaluated in parallel, whereas for offline application, an optimization approach is employed. Here, one model with several fault size parameters is regarded and the optimal fault size parameters are determined by means of an interval halving technique. Both techniques have been evaluated at a testbed and have shown very good fault detection and diagnosis capabilities.

关键词： Hydraulic Actuators Fault Diagnosis Sensor Failures Physical Models Optimization

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Displacement Sensor Fault Tolerance for Hydraulic Servo Axis

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IFAC Proceedings Volumes 2008年第2期41卷 13803-13808页

作者： Marco Muenchhof Technische Universitaet Darmstadt Institute of Automatic Control Laboratory for Control Systems and Process Automation Darmstadt Germany (Tel: +49-6151-16-3114

In this paper, a fault management system for a hydraulic servo axis is described. This system is capable of sustaining faults in the piston displacement sensor of the position-controlled hydraulic servo axis. By means of a parity equation based fault detection stage, faults in the displacement sensor as well as other sensors and components of the servo axis can be detected and subsequently be diagnosed by means of a fuzzy-logic based reasoning system. Upon the diagnosis of a piston displacement sensor fault, the system switches to a “model-sensor” which provides an estimate for the piston position. To ensure the utmost model fidelity of the model sensor, the model parameters are constantly updated by means of parameter estimation during the fault-free operation of the servo axis. Experiments at a hydraulic servo axis conclude this paper and show the high quality of the reconstructed piston displacement sensor signal.

关键词： Hydraulic Actuators Fault Diagnosis Fault Tolerance Sensor Failures Physical Models Parameter Estimation

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'Cycle to cycle' optimizing control of simulated moving beds - Experimental implementation for a nonlinear chiral separation

'Cycle to cycle' optimizing control of simulated moving beds...

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2008 AIChE Annual Meeting, AIChE 100

作者： Grossmann, Cristian Langel, Christian Mazzotti, Marco Morari, Manfred Morbidelli, Massimo Automatic Control Laboratory ETH Zurich Zurich Switzerland Institute for Process Engineering ETH Zurich Zurich Switzerland Department of Chemistry and Applied Biosciences Institute for Chemical and Bioengineering ETH Zurich Wolfgang-Pauli-Str. 10 Zurich 8093 Switzerland

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