检索结果-内蒙古大学图书馆

Novel control Vector Parameterization Method with Differential Evolution Algorithm and Its Application in Dynamic optimization of chemical processes

引用

Chinese Journal of chemical Engineering 2013年第1期21卷 64-71页

作者：孙帆钟伟民程辉钱锋 Key Laboratory of Advanced Control and Optimization for Chemical Processes (Ministry of Education) East China University of Science and Technology Department of Automation East China University of Science and Technology

Two general approaches are adopted in solving dynamic optimization problems in chemical processes, namely, the analytical and numerical methods. The numerical method, which is based on heuristic algorithms, has been widely used. An approach that combines differential evolution （DE） algorithm and control vector parameteri- zation （CVP） is proposed in this paper. In the proposed CVP, control variables are approximated with polynomials based on state variables and time in the entire time interval. Region reduction strategy is used in DE to reduce the width of the search region, which improves the computing efficiency. The results of the case studies demonstrate the feasibility and efficiency of the oroposed methods.

关键词： control vector pararneterization differential evolution algorithm dynamic optimization chemical processes

来源：评论

学校读者我要写书评

暂无评论

Automatic Sleep Stage Classification for Daytime Nap Based on Hopfield Neural Network

Automatic Sleep Stage Classification for Daytime Nap Based o...

引用

第25届中国控制与决策会议

作者： Xi Chen Bei Wang Xingyu Wang Key Laboratory of Advanced Control and Optimization for Chemical Processes (East China University of Science and Technology) Ministry of Education School of Information Science and Engineering East China University of Science and Technology

ISBN: (纸本)9781467355339

In this study, automatic method of sleep stage classification for daytime nap is investigated. The ultimate objective is to identify the changing of sleep level during one's nap. The sleep data is recorded according to the polysomnographic (PSG) measurement. The Electroencephalograph (EEG) is analyzed for sleep stage classification. Totally, 4 parameters are selected and calculated for each 20-second segment of EEG data. The main method is based on Hopfield Neural Network (HNN). The neural network is trained by using standard mode. The sleep stages are classified based on HNN for each consecutive segment. The obtained result showed about 80.6% consistence comparing with the visual inspection. The automatic classification results indicated the changing of sleep level during nap, which can be useful for daytime nap sleep evaluation.

关键词： Sleep Stage Determination, Daytime Nap, EEG, Hopfield Neural Network

来源：评论

学校读者我要写书评

暂无评论

Modeling and optimization for ethylene cracking furnace systems scheduling with consideration of changing feedstock

引用

Huagong Xuebao/CIESC Journal 2013年第12期64卷 4304-4312页

作者： Shang, Baopeng Du, Wenli Jin, Yangkun Qian, Feng Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and Technology Shanghai 200237 China

An ethylene plant employs multiple cracking furnaces in parallel to convert various hydrocarbon feedstocks to smaller hydrocarbon molecules. The continuous operational performance of cracking furnaces gradually decays because of coke formation in the reaction coils, which requires each furnace to be periodically shut down for decoking. Given multiple feeds and different cracking furnaces as well as various product prices and manufacturing costs, the operational scheduling for the entire furnace system should be optimized to achieve the best economic performance. In this paper, a new MINLP(mixed-integer nonlinear programming) model is developed to obtain cyclic scheduling strategies for cracking furnace systems. Compared to previous studies, the new model has more capabilities to address operation profitability of multiple feeds cracked in multiple furnaces. Meanwhile, solving the problem of the choice for the right time of changing feedstock in the process of cracking furnace, case studies demonstrate the efficacy of the developed methodology. © All Rights Reserved.

关键词： Feedstocks

来源：评论

学校读者我要写书评

暂无评论

Feed property identification of ethylene cracking based on improved fuzzy C-mean clustering algorithm

引用

Huagong Xuebao/CIESC Journal 2013年第12期64卷 4366-4372页

作者： Li, Jiawen Du, Wenli Li, Jinlong Qian, Feng Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and Technology Shanghai 200237 China

In ethylene cracking process, the changes of feed have many kinds, and due to its expensive feed analyzer, little industrial site equips with it, so online recognition of oil property is important to achieve cracking online optimization. As the traditional fuzzy C-means algorithm is based on the membership of the strike Euclidean distance, the algorithm contains only the mean center, bringing the unity of clustering results. To take full advantage of effective information of cracking feed, this paper proposes a fuzzy membership set method based on hybrid probabilistic model, namely through the establishment of Gaussian mixture model to achieve describing the probability distribution of clustering sample's affiliation, and use EM algorithm to estimate the model parameter's pole maximum likelihood. The algorithm can not only consider mean center of the sample, but also effectively use sample covariance and the weight coefficient information for mode discrimination. Finally, the simulation is based on classic IRIS data clustering and ethylene cracking feedstock identification, verifying the method described in this paper in the index of dunn and Xiebieni is better than fuzzy C-means clustering algorithm, showing that the method is effective. © All Rights Reserved.

关键词： Clustering algorithms

来源：评论

学校读者我要写书评

暂无评论

Synchronization of Nonlinear Coupled Networks with Time-delay via Distributed Impulsive control

Synchronization of Nonlinear Coupled Networks with Time-dela...

引用

第三十二届中国控制会议

作者： ZHANG Hao FENG Gang YAN Huaicheng CHEN Qijun Department of Control Science and Engineering Tongji University Department of Mechanical & Biomedical Engineering City University of Hong Kong Key Laboratory of Advanced Control and Optimization for Chemical Processes of Ministry of Education School of Information Science and Engineering East China University of Science and Technology

ISBN: (纸本)9781479900305

In this paper,the synchronization of a nonlinear network with time-varying coupling delay is investigated via distributed impulsive *** objective is to design the distributed impulsive controller with minimum coupling strength such that the nonlinear network with coupling delay is globally exponentially *** sufficient conditions have been derived based on Lyapunov-Razumikhin method in terms of matrix *** example is presented to illustrate the effectiveness of the proposed control methods.

关键词： Global exponential synchronization Distributed impulsive control Time-varying delay Coupled network

来源：评论

学校读者我要写书评

暂无评论

Modeling and optimization of the Steam Turbine Network of an Ethylene Plant

引用

Chinese Journal of chemical Engineering 2013年第5期21卷 520-528页

作者：李泽秋赵亮杜文莉钱锋 Key Laboratory of Advanced Control and Optimization for chemical Process (hTlinistry of t~ducation) East ChinaUniversity of Science and Technology Shanghai 200237 China

In this paper,we developed a hybrid model for the steam turbines of a utility system,which combines an improved neural network model with the thermodynamic ***,a nonlinear programming(NLP) model of the steam turbine network is formulated by utilizing the developed steam turbine models to minimize the total steam cost for the whole steam turbine ***,this model is applied to optimize the steam turbine network of an ethylene *** obtained results demonstrate that this hybrid model can accurately estimate and evaluate the performance of steam turbines,and the significant cost savings can be made by optimizing the steam turbine network operation at no capital cost.

关键词： hybrid model steam turbine network utility system economic objective

来源：评论

学校读者我要写书评

暂无评论

Adaptive neural output feedback control for stochastic nonlinear systems with unknown control directions

Adaptive neural output feedback control for stochastic nonli...

引用

第三十二届中国控制会议

作者： Yu Zhaoxu Li Shugang Key Laboratory of Advanced Control and Optimization for Chemical Process of Ministry of Education East China University of Science and Technology Department of Industrial Engineering and Logistics Shanghai Jiao Tong University

ISBN: (纸本)9781479900305

This paper focuses on the problem of adaptive output feedback stabilization for a class of stochastic nonlinear system with unknown control *** using a linear state transformation,the unknown control coefficients are lumped together, such that the original system is transformed to a new system for which control design becomes *** employing the inputdriven observer,a novel adaptive neural network(NN) output-feedback controller which only contains one adaptive parameter is developed for such systems by using backstepping technique and NNs' *** proposed control design guarantees that all the signals in the closed-loop systems are 4-moment semi-globally uniformly ultimately bounded.

关键词： stochastic systems output-feedback neural network(NN) Nussbaum function backstepping

来源：评论

学校读者我要写书评

暂无评论

Outlet Temperature Correlation and Prediction of Transfer Line Exchanger in an Industrial Steam Ethylene Cracking Process

引用

Chinese Journal of chemical Engineering 2013年第4期21卷 388-394页

作者：金阳坤李进龙杜文莉王振雷钱锋 Key Laboratory of Advanced Control and Optimization for Chemical Processes of Ministry of Education East China University of Science and Technology Shanghai 200237 China Institute of Automation East China University of Science and Technology Shanghai 200237 China

Predicting the best shutdown time of a steam ethylene cracking furnace in industrial practice remains a challenge due to the complex coking process. As well known, the shutdown time of a furnace is mainly determined by coking condition of the transfer line exchangers （TLE） when naphtha or other heavy hydrocarbon feedstocks are cracked. In practice, it is difficult to measure the coke thickness in TLE through experimental method in the complex industrial situation. However, the outlet temperature of TLE （TLEOT） can indirectly characterize the coking situation in TLE since the coke accumulation in TLE has great influence on TLEOT. Thus, the TLEOT could be a critical factor in deciding when to shut down the furnace to decoke. To predict the TLEOT, a paramewic model was proposed in this work, based on theoretical analysis, mathematic reduction, and parameters estimation. The feasibility of the proposed model was further checked through industrial data and good agreements between model prediction and industrial data with maximum deviation 2% were observed.

关键词： transfer line exchanger outlet temperature parametric model steam ethylene cracking

来源：评论

学校读者我要写书评

暂无评论

A novel second order sliding mode control algorithm for velocity control permanent magnet synchronous motor

Communications in Computer and Information Science

引用

Communications in Computer and Information Science 2013年 355卷 213-220页

作者： Qi, Liang Shi, Hongbo Key Laboratory of Advanced Control Optimization for Chemical Processes of Ministry of Education East China University of Science and Technology 200237 Shanghai China

This paper focuses on performance improvements of the permanent magnet synchronous motor (PMSM) vector control. In this paper, a novel second order sliding mode control (SOSMC) algorithm is presented to accomplish velocity control of the PMSM. The integral manifold is utilized to avoid noise signals being amplified because of the acceleration information in control system, and the second order sliding mode control law is achieved by a Lyapunov function approach. The novel method can successfully eliminate the system chattering problem and improve the performance of the PMSM control system, such as fast response, high robustness and tracking speed performance. Meanwhile, an anti-windup control method is used to solve the problem of the windup phenomenon of the PMSM control system. The experimental results show that the proposed method is feasible and effective and is capable of controlling the permanent magnet synchronous motor. © Springer-Verlag Berlin Heidelberg 2013.

关键词： Lyapunov functions

来源：评论

学校读者我要写书评

暂无评论

Analysis and modeling of GTAW weld pool geometry

Communications in Computer and Information Science

引用

Communications in Computer and Information Science 2013年 355卷 284-293页

作者： Wang, XueWu Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and Technology 200237 Shanghai China

A three dimensional vision sensing system was used to mimic the human vision system to observe the three-dimensional weld pool surface in pipe Gas Tungsten Arc Welding (GTAW) process. Novel characteristic parameters containing information about the penetration state specified by its back-side weld pool width and height were proposed based on the reconstructed three dimensional weld pool surfaces. In order to obtain the penetration status in real time conveniently, a neural network model was established to estimate the penetration based on the proposed characteristic parameters. It was found that the top-side characteristic parameters proposed can reflect the back-side weld pool parameters accurately and the neural network is capable of predicting the penetration status in real time by observing the three-dimensional weld pool surface which is beneficial for penetration control of GTAW process. © Springer-Verlag Berlin Heidelberg 2013.

关键词： Gas metal arc welding

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：