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Data-driven optimal operation of the industrial methanol to olefin process based on relevance vector machine

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Chinese Journal of Chemical Engineering 2021年第6期34卷 106-115页

作者： zhiquan wang Liang wang Zhihong Yuan Bingzhen Chen Department of Chemical Engineering Tsinghua UniversityBeijing 100084China State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

Methanol to olefin(MTO)technology provides the opportunity to produce olefins from nonpetroleum sources such as coal,biomass and natural *** than 20 commercial MTO plants have been put into *** now,contributions on optimal operation of industrial MTO plants from a process systems engineering perspective are *** on relevance vector machine(RVM),a data-driven framework for optimal operation of the industrial MTO process is established to fully utilize the plentiful industrial data *** correlates the yield distribution prediction of main products and the operation *** correlations then serve as the constraints for the multi-objective optimization model to pursue the optimal operation of the *** sorting genetic algorithmⅡis used to solve the optimization *** tests demonstrate that the ethylene yield is effectively improved based on the proposed *** RVM does provide the distribution prediction instead of point estimation,the established model is expected to provide guidance for actual production operations under uncertainty.

关键词： Methanol to olefins Relevance vector machine Genetic algorithm Operation optimization Systems engineering Process systems

Satisfactory fault-tolerant controller design for uncertain systems subject to actuator faults

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仪器仪表学报 2008年第5期29卷 921-926页

作者： Zhang Dengfeng Su Hongye wang zhiquan Institute of Advanced Process Control Zhejiang University Hangzhou 310027 China Key Lab of Digital Manufacturing Technology Huaiyin Institute of Technology Huai＇an 223001 China School of Automation Nanjing University of Science and Technology Nanjing 210094 China

Based on satisfactory control strategy,a new method for robust passive fault tolerant controller is proposed for a class of uncertain discrete-time systems subject to actuator *** state-feedback gain matrix is calculated by linear matrix inequality(LMI)*** designed controller guarantees that the closed-loop system meets the pre-specified consistent constraints on circular pole index and steady-state variance index simultaneously for normal case and possible actuator fault *** consistency of the performance indices is ***,with the mentioned indices constraints,a solution is obtained by convex optimal technique for the robust satisfactory fault-tolerant controller with optimal control-cost.

关键词：控制器设计方案不确定性误差机械仪器

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太赫兹波光电导天线探测器的研究进展

渭南师范学院学报 2024年第8期39卷 79-87,94页

作者：王志全董陈岗王欣渭南师范学院物理与电气工程学院陕西渭南714099

对国内外利用光电导天线探测器检测偏振太赫兹波进行了归纳总结,发现国内外对用于太赫兹偏振检测的光电导天线探测器的研发各有优缺点,但不能同时满足高效率、高精度、高信噪比的要求。因此,通过对光电导天线阵列探测器的有源区域、相... 详细信息

对国内外利用光电导天线探测器检测偏振太赫兹波进行了归纳总结,发现国内外对用于太赫兹偏振检测的光电导天线探测器的研发各有优缺点,但不能同时满足高效率、高精度、高信噪比的要求。因此,通过对光电导天线阵列探测器的有源区域、相邻阵元之间的反向电流和探测准确性等进行国内外研究现状和发展动态梳理,分析光电导阵列探测器在太赫兹偏振检测中所遇到的关键问题,为光电导天线阵列探测器的研发和应用提供一定的参考。

关键词：太赫兹波光电导天线偏振光

Detecting JPEG image forgery based on double compression

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Journal of Systems Engineering and Electronics 2009年第5期20卷 1096-1103页

作者： wang Junwen Liu Guangjie Dai Yuewei wang zhiquan School of Automation Nanjing Univ. of Science &: Technology Nanjing 210094 P. R. China

Detecting the forgery parts from a double compressed image is very important and urgent work for blind authentication. A very simple and efficient method for accomplishing the task is proposed. Firstly, the probabilistic model with periodic effects in double quantization is analyzed, and the probability of quantized DCT coefficients in each block is calculated over the entire iraage. Secondly, the posteriori probability of each block is computed according to Bayesian theory and the results mentioned in first part. Then the mean and variance of the posteriori probability are to be used for judging whether the target block is tampered. Finally, the mathematical morphology operations are performed to reduce the false alarm probability. Experimental results show that the method can exactly locate the doctored part, and through the experiment it is also found that for detecting the tampered regions, the higher the second compression quality is, the more exact the detection efficiency is.

关键词： image forgery JPEG double compression quantization posteriori probability.

Research on robust mean square stability of networked control systems with packet dropout

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Journal of Systems Engineering and Electronics 2010年第1期21卷 95-101页

作者： Dexiao Xie Xiaodong Han He Huang zhiquan wang School of Automation Nanjing University of Science and Technology Nanjing 210094 P. R. China Beijing Institute of Satellite Information Engineering China Academy of Space Technology Beijing 100094 E R. China

This paper is concerned with the robust stabilization problem of networked control systems with stochastic packet dropouts and uncertain parameters. Considering the stochastic packet dropout occuring in two channels between the sensor and the controller, and between the controller and the actuator, networked control systems are modeled as the Markovian jump linear system with four operation modes. Based on this model, the necessary and sufficient conditions for the mean square stability of the deterministic networked control systems and uncertain networked control systems are given by using the theory of the Markovian jump linear system, and corresponding controller design procedures are proposed via the cone complementarity linearization method. Finally, the numerical example and simulations are given to illustrate the effectiveness of the proposed results.

关键词： networked control system packet dropout meansquare stability Markovian jump linear system.

Enterprise-wide optimization of integrated planning and scheduling for refinery-petrochemical complex with heuristic algorithm

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Frontiers of Chemical Science and Engineering 2023年第10期17卷 1516-1532页

作者： Lifeng Zhang Haoyang Hu zhiquan wang Zhihong Yuan Bingzhen Chen State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

This paper focuses on the integrated problem of long-term planning and short-term scheduling in a largescale refinery-petrochemical complex,and considers the overall manufacturing process from the upstream refinery to the downstream petrochemical *** time scales are incorporated from the planning and scheduling *** the end of each discrete time period,additional constraints are imposed to ensure material balance between different time *** time representation is applied to the planning subproblem,while continuous time is applied to the scheduling of ethylene cracking and polymerization processes in the petrochemical *** enterprise-wide mathematical model is formulated through mixed integer nonlinear *** solve the problem efficiently,a heuristic algorithm combined with a convolutional neural network(CNN),is *** variables are used as the CNN input,leading to the integration of a data-driven approach and classical optimization by which a heuristic algorithm is *** results do not only illustrate the detailed operations in a refinery and petrochemical complex under planning and scheduling,but also confirm the high efficiency of the proposed algorithm for solving large-scale problems.

关键词： planning scheduling refinery-petrochemical convolutional neural network heuristic algorithm

Robust H_∞ guaranteed cost satisfactory fault-tolerant control for discrete-time systems with quadratic D stabilizability

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Journal of Systems Engineering and Electronics 2010年第3期21卷 496-502页

作者： Xiaodong Han Jiangong Liu Dexiao Xie Dengfeng Zhang zhiquan wang Institute of Telecommunication Satellite China Academy of Space Technology Beijing 100094 P. R. China School of Automation Nanjing University of Science and Technology Nanjing 210094 E R. China

The problem of robust H∞ guaranteed cost satisfactory fault-tolerant control with quadratic D stabilizability against actuator failures is investigated for a class of discrete-time systems with value-bounded uncertainties existing in both the state and control input *** on a more practical and general model of actuator continuous gain failures,taking the transient property,robust behaviour on H∞ performance and quadratic cost performance requirements into consideration,sufficient conditions for the existence of satisfactory fault-tolerant controller are given and the effective design steps with constraints of multiple performance indices are ***,the consistency of the regional pole index,H∞ norm-bound constraint and cost performance indices is set up for fault-tolerant control.A simulation example shows the effectiveness of the proposed method.

关键词： fault-tolerant control actuator failures consistency theory quadratic D stabilizability.

SolidWorks与机械制图有机融合的教学实践

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甘肃高师学报 2024年第2期29卷 79-83页

作者：王志全王振禄魏伟刘善春兰州城市学院培黎机械工程学院甘肃兰州730070

SolidWorks软件以其用户友好的界面和丰富的功能模块,能够有效地支持机械制图教学,促进理论知识的掌握与实践技能的有效提高.文章依托SolidWorks软件作为辅助教学平台,通过利用机械制图与计算机辅助设计技术的有机融合,采用“一题两作... 详细信息

SolidWorks软件以其用户友好的界面和丰富的功能模块,能够有效地支持机械制图教学,促进理论知识的掌握与实践技能的有效提高.文章依托SolidWorks软件作为辅助教学平台,通过利用机械制图与计算机辅助设计技术的有机融合,采用“一题两作”项目式教学模式,将学生的理论学习与实际操作紧密结合,以此提升学生的应用技能和创新思维.这种教学模式对于推动工程教育发展和培养应用型人才具有重要的作用.

关键词： SolidWorks软件机械制图一题两作项目式教学

Analysis of on-chip distributed interconnects based on Pade expansion

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控制理论与应用（英文版） 2009年第1期7卷 92-96页

作者： Xiaopeng JI Long GE zhiquan wang College of Automation. Nanjing University of Science and Technology Nanjing Jiangsu 210094 China

In this paper, on-chip interconnects are modeled as distributed parameter RLCG transmission lines, based on which the matrix ABCD of interconnects is deduced. With help of the ABCD matrix, a voltage transfer function of an interconnect system, consisting of a driver, interconnect line and load, is obtained analytically in the form of a transcendental function, and it is reduced to a finite order system based on high order Pade approximation. With the reduced-order transfer function, response waveforms with step input can be obtained, and signal delay can be calculated consequently. Two numerical experiments are conducted to demonstrate its efficiency.

关键词： Distributed interconnects ABCD matrix Transfer function Pade expansion Response waveform Signal delay