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A closed-loop particle swarm optimizer for multivariable process controller design

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第8期9卷 1050-1060页

作者： Kai HAN Jun ZHAO Zu-hua XU ji-xin qian State Key Lab of Industrial Control Technology Institute of Industrial Process Control Zhejiang University Hangzhou 310027 China

Design of general multivariable process controllers is an attractive and practical alternative to optimizing design by evolutionary algorithms (EAs) since it can be formulated as an optimization problem. A closed-loop particle swarm optimization (CLPSO) algorithm is proposed by mapping PSO elements into the closed-loop system based on control theories. At each time step, a proportional integral (PI) controller is used to calculate an updated inertia weight for each particle in swarms from its last fitness. With this modification, limitations caused by a uniform inertia weight for the whole population are avoided, and the particles have enough diversity. After the effectiveness, efficiency and robustness are tested by benchmark functions, CLPSO is applied to design a multivariable proportional-integral-derivative (PID) controller for a solvent dehydration tower in a chemical plant and has improved its performances.

关键词： Multivariable process control Proportional-integral-derivative (PID) control Model predictive control (MPC) Particle swarm optimization (PSO) Closed-loop system

Simultaneous approach for simulation of a high-temperature gas-cooled reactor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 567-574页

作者： Yang CHEN jiang-hong YOU Zhi-jiang SHAO Ke-xin WANG ji-xin qian State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China

The simulation of a high-temperature gas-cooled reactor pebble-bed module(HTR-PM) plant is *** lumped parameter model has the form of a set differential algebraic equations(DAEs) that include stiff equations to model point neutron *** nested approach is the most common method to solve DAE,but this approach is very expensive and time-consuming due to inner *** paper deals with an alternative approach in which a simultaneous solution method is *** DAEs are discretized over a time horizon using collocation on finite elements,and Radau collocation points are *** resulting nonlinear algebraic equations can be solved by existing *** discrete algorithm is discussed in detail;both accuracy and stability issues are ***,the simulation results are presented to validate the efficiency and accuracy of the simultaneous approach that takes much less time than the nested one.

关键词： Differential algebraic equations(DAEs) High-temperature gas-cooled reactor(HTR) Simulation Simultaneous approach

Model predictive control with an on-line identification model of a supply chain unit

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第5期11卷 394-400页

作者： jian NIU Zu-hua XU Jun ZHAO Zhi-jiang SHAO ji-xin qian State Key Lab of Industrial Control Technology Zhejiang University Hangzhou 310027 China

A model predictive controller was designed in this study for a single supply chain unit.A demand model was described using an autoregressive integrated moving average(ARIMA) model,one that is identified on-line to forecast the future *** was used to modify the demand prediction,and profit was chosen as the control *** imitate reality,the purchase price was assumed to be a piecewise linear form,whereby the control objective became a nonlinear *** addition,a genetic algorithm was introduced to solve the *** were put on the predictive inventory to control the inventory fluctuation,that is,the bullwhip effect was *** model predictive control(MPC) method was compared with the order-up-to-level(OUL) method in *** results revealed that using the MPC method can result in more profit and make the bullwhip effect controllable.

关键词： Supply chain Model predictive control On-line identification Optimization with constraint Piecewise linear price

Reduced precision solution criteria for nonlinear model predictive control with the feasibility-perturbed sequential quadratic programming algorithm

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第11期12卷 919-931页

作者： jiao-na WAN Zhi-jiang SHAO Ke-xin WAN Xue-yi FANG Zhi-qiang WANG ji-xin qian State Key Lab of Industrial Control Technology Institute of Industrial Control Department of Control Science and Engineering Zhejiang University Hangzhou 310027 China

We propose a novel kind of termination criteria, reduced precision solution (RPS) criteria, for solving optimal control problems (OCPs) in nonlinear model predictive control (NMPC), which should be solved quickly for new inputs to be applied in time. Computational delay, which may destroy the closed-loop stability, usually arises while non-convex and nonlinear OCPs are solved with differential equations as the constraints. Traditional termination criteria of optimization algorithms usually involve slow convergence in the solution procedure and waste computing resources. Considering the practical demand of solution precision, RPS criteria are developed to obtain good approximate solutions with less computational cost. These include some indices to judge the degree of convergence during the optimization procedure and can stop iterating in a timely way when there is no apparent improvement of the solution. To guarantee the feasibility of iterate for the solution procedure to be terminated early, the feasibility- perturbed sequential quadratic programming (FP-SQP) algorithm is used. Simulations on the reference tracking performance of a continuously stirred tank reactor (CSTR) show that the RPS criteria efficiently reduce computation time and the adverse effect of computational delay on closed-loop stability.

关键词： Nonlinear model predictive control (NMPC) Computational delay Termination criteria Continuously stirred tankreactor (CSTR)

Stochastic Multiresonance Induced by an Optimal Noise Pulse Interval Due to Hopping of Energy Levels

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Chinese Physics Letters 2001年第7期18卷 870-873页

作者： ZHANG ji-qian xin Hou-Wen Department of Chemical Physics University of Science and Technology of ChinaHefei 230026

An interesting phenomenon,called the Stochastic multiresonance(SMR),induced by the variation of the noise pulse interval,is described and the formative mechanism of SMR is investigated by using the concept of hopping between different energy ***,the SMR can be realized by choosing the optimal noise pulse interval or selecting the appropriate noise intensity.

关键词： resonance SMR Optimal

Impacts of meteorological parameters on the occurrence of air pollution episodes in the Sichuan basin

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Journal of Environmental Sciences 2022年第4期34卷 308-321页

作者： qian Guo Dongyou Wu Chunxue Yu Tianshuang Wang Mingxia ji xin Wang Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China Research Center for Eco-environmental Engineering Dongguan University of TechnologyDongguan 523808China

Episodes of fine-particulate matter(PM_(2.5))pollution are a widespread and common occurrence in China,and have potentially serious implications for human *** conditions play an important role in air quality and influence the formation of regional air pollution *** study applied a new classification method and daily PM_(2.5)concentration data to(a)evaluate different levels of air pollution in the Sichuan-Chongqing region between 2015 and 2017,and(b)investigate their relationships with meteorological parameters including atmospheric boundary layer height,wind speed,temperature inversion,weather type,and atmospheric *** identified a total of 40 air pollution episodes,the most severe of which occurred in winter when the atmospheric layer height was *** heavy pollution events also coincided with low surface(10 m)wind speeds and temperature inversions,weather conditions that generally result from low pressure over the northwestern Sichuan Basin(90-102°E,28-36°N)and southerly atmospheric transport.

关键词： Air pollution Pollution episode PM_(2.5) Meteorological factors

Chaotic Identification and Prediction of Silicon Content in Hot Metal

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Journal of Iron and Steel Research International 2005年第5期12卷 3-5,46页

作者： GAO Chuan-hou ZHOU Zhi-min qian ji-xin Zhejiang University Hangzhou 310027 China

The time series data of silicon content in hot metal were identified to have the chaotic feature because of the positive maximum Lyapunov exponent, and then the time scales to predict future were estimated. Finally a chaotic local-region model was constructed to predict silicon content in hot metal with good performance due to high hitting rate.

关键词： blast furnace silicon content hot metal chaos Lyapunov spectra prediction

彼得·马修森从地方到全球的生态旅行书写研究

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佳木斯大学社会科学学报 2025年第1期43卷 130-133,138页

作者：王倩季文合肥职业技术学院基础教育学院安徽合肥238000

彼得·马修森是美国知名作家和环保主义者,其小说中多次围绕生态旅行和自然主题展开。他以清新的笔触为读者展开了一场场人类与自然的博弈,这既是人类向自然界进发的探险之旅,更是人类内心深处的自我探索之旅。彼得·马修森借助生态旅... 详细信息

彼得·马修森是美国知名作家和环保主义者,其小说中多次围绕生态旅行和自然主题展开。他以清新的笔触为读者展开了一场场人类与自然的博弈,这既是人类向自然界进发的探险之旅,更是人类内心深处的自我探索之旅。彼得·马修森借助生态旅行书写,表达了对自然世界的独特理解,以及对人类与自然之间复杂关系的思考。透过这些作品,马修森展示了其对自然界的深刻洞察力及对地球上各种生态系统和不同文化的尊重。从多元化、现实与虚拟以及归宿三个维度对彼得·马修森从地方到全球的生态旅行书写展开研究。

关键词：彼得·马修森生态旅行书写自然界救赎

Modified calcination conditions of rare alkali metal Rb-containing muscovite(KAl_2[AlSi_3O_(10)](OH)_2)

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Rare Metals 2013年第6期32卷 632-635页

作者： Zhi-qiang Shan xin-qian Shu ji-Fu Feng Wei-Ning Zhou School of Chemical and Environmental Engineering China University of Mining & Technology Comprehensive Utilization Research Institute of Resource Guilin Research Institute Geology for Mineral Resources

Muscovite mineral was roasted in different *** leaching rate was a standard to examine the impact of various factors on calcination effect,including the agent types,roasting time,mass ratio,and roasting *** results indicate that the best agent is the combination of sodium chloride and calcium chloride,and its mass ratio of muscovite/NaCl/CaCl2is1.00:0.25:*** at 850℃ for 30 min,the rubidium leaching rate is up to 90.12%.The reaction of muscovite ore with the chlorinating agent CaCl2was studied by TG/DSC,and the surface morphology before and after leaching was characterized by *** chloride products can be obtained using t-BAMBP extraction,hydrochloric acid re-extraction,and purification.

关键词： Modified calcination Muscovite ore Chlorinating agent