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Mathematical Modeling and Control Algorithm Development for Bidirectional Power Flow in CCS-CNT System
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作者 Sinqobile Wiseman Nene 《Journal of Power and Energy Engineering》 2024年第9期131-143,共12页
As the demand for more efficient and adaptable power distribution systems intensifies, especially in rural areas, innovative solutions like the Capacitor-Coupled Substation with a Controllable Network Transformer (CCS... As the demand for more efficient and adaptable power distribution systems intensifies, especially in rural areas, innovative solutions like the Capacitor-Coupled Substation with a Controllable Network Transformer (CCS-CNT) are becoming increasingly critical. Traditional power distribution networks, often limited by unidirectional flow capabilities and inflexibility, struggle to meet the complex demands of modern energy systems. The CCS-CNT system offers a transformative approach by enabling bidirectional power flow between high-voltage transmission lines and local distribution networks, a feature that is essential for integrating renewable energy sources and ensuring reliable electrification in underserved regions. This paper presents a detailed mathematical representation of power flow within the CCS-CNT system, emphasizing the control of both active and reactive power through the adjustment of voltage levels and phase angles. A control algorithm is developed to dynamically manage power flow, ensuring optimal performance by minimizing losses and maintaining voltage stability across the network. The proposed CCS-CNT system demonstrates significant potential in enhancing the efficiency and reliability of power distribution, making it particularly suited for rural electrification and other applications where traditional methods fall short. The findings underscore the system's capability to adapt to varying operational conditions, offering a robust solution for modern power distribution challenges. 展开更多
关键词 Capacitor Couple Substation Ferroresonance Power Flow Control Controllable Network Controller Capacitor-Coupled Substation Incorporating Controllable Network Transformer (CCS-CNT) System System modeling
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Hierarchical Modeling by Recursive Unsupervised Spectral Clustering and Network Extended Importance Measures to Analyze the Reliability Characteristics of Complex Network Systems 被引量:1
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作者 Yiping Fang Enrico Zio 《American Journal of Operations Research》 2013年第1期101-112,共12页
The complexity of large-scale network systems made of a large number of nonlinearly interconnected components is a restrictive facet for their modeling and analysis. In this paper, we propose a framework of hierarchic... The complexity of large-scale network systems made of a large number of nonlinearly interconnected components is a restrictive facet for their modeling and analysis. In this paper, we propose a framework of hierarchical modeling of a complex network system, based on a recursive unsupervised spectral clustering method. The hierarchical model serves the purpose of facilitating the management of complexity in the analysis of real-world critical infrastructures. We exemplify this by referring to the reliability analysis of the 380 kV Italian Power Transmission Network (IPTN). In this work of analysis, the classical component Importance Measures (IMs) of reliability theory have been extended to render them compatible and applicable to a complex distributed network system. By utilizing these extended IMs, the reliability properties of the IPTN system can be evaluated in the framework of the hierarchical system model, with the aim of providing risk managers with information on the risk/safety significance of system structures and components. 展开更多
关键词 COMPLEX NETWORK System Hierarchical modeling Spectral Clustering EXTENDED IMPORTANCE Measure
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DTHMM based delay modeling and prediction for networked control systems 被引量:2
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作者 Shuang Cong Yuan Ge +2 位作者 Qigong Chen Ming Jiang Weiwei Shang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1014-1024,共11页
In the forward channel of a networked control system (NCS), by defining the network states as a hidden Markov chain and quantizing the network-induced delays to a discrete sequence distributing over a finite time in... In the forward channel of a networked control system (NCS), by defining the network states as a hidden Markov chain and quantizing the network-induced delays to a discrete sequence distributing over a finite time interval, the relation between the network states and the network-induced delays is modelled as a discrete-time hidden Markov model (DTHMM). The expectation maximization (EM) algorithm is introduced to derive the maximumlikelihood estimation (MLE) of the parameters of the DTHMM. Based on the derived DTHMM, the Viterbi algorithm is introduced to predict the controller-to-actuator (C-A) delay during the current sampling period. The simulation experiments demonstrate the effectiveness of the modelling and predicting methods proposed. 展开更多
关键词 networked control system discrete-time hidden Markov model network state delay prediction.
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Integration of Management Systems: A Process Based Model
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作者 QI Guo-you ZENG Sai-xing +1 位作者 JIA Yan-hong LIANG Dong-ling 《Journal of Northeast Agricultural University(English Edition)》 CAS 2005年第2期151-154,共4页
The paper discusses the barriers of integration of management systems (IMS). A model based on process is explored, It is indicated that integrating management systems should not ignore the characteristics of the man... The paper discusses the barriers of integration of management systems (IMS). A model based on process is explored, It is indicated that integrating management systems should not ignore the characteristics of the management systems, especially scope issues. IMS needs to take into the continuous improvement. 展开更多
关键词 management systems integration PROCESS model
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The Complex System Modeling Method Based on Uniform Design and Neural Network 被引量:1
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作者 Zhang Yong(Beijing Simulation Center, P.O.Box 142-23, Beijing 100854, P.R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1996年第4期27-36,共10页
In this paper, the method based on uniform design and neural network is proposed to model the complex system. In order to express the system characteristics all round, uniform design method is used to choose the model... In this paper, the method based on uniform design and neural network is proposed to model the complex system. In order to express the system characteristics all round, uniform design method is used to choose the modeling samples and obtain the overall information of the system;for the purpose of modeling the system or its characteristics, the artificial neural network is used to construct the model. Experiment indicates that this method can model the complex system effectively. 展开更多
关键词 modeling method Uniform design Neural network Complex system Simulation.
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On the model-based networked control for singularly perturbed systems 被引量:1
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作者 Hongwang YU Zhiming WANG Yufan ZHENG 《控制理论与应用(英文版)》 EI 2008年第2期153-162,共10页
In this paper, the control of a two-time-scale plant, where the sensor is connected to a linear controller/ actuator via a network is addressed. The slow and fast systems of singularly perturbed systems are used to pr... In this paper, the control of a two-time-scale plant, where the sensor is connected to a linear controller/ actuator via a network is addressed. The slow and fast systems of singularly perturbed systems are used to produce an estimate of the plant state behavior between transmission times, by which one can reduce the usage of the network. The approximate solutions of the whole systems are derived and it is shown that the whole systems via the network control are generally asymptotically stable as long as their slow and fast systems are both stable. These results are also extended to the case of network delay. 展开更多
关键词 model-based networked control systems Singularly perturbed control systems Asymptotically stable Globally practical stability
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Enhancing Feature Discretization in Alarm and Fire Detection Systems Using Probabilistic Inference Models
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作者 Joe Essien 《Journal of Computer and Communications》 2023年第7期140-155,共16页
Sensors for fire alarms require a high level of predictive variables to ensure accurate detection, injury prevention, and loss prevention. Bayesian networks can aid in enhancing early fire detection capabilities and r... Sensors for fire alarms require a high level of predictive variables to ensure accurate detection, injury prevention, and loss prevention. Bayesian networks can aid in enhancing early fire detection capabilities and reducing the frequency of erroneous fire alerts, thereby enhancing the effectiveness of numerous safety monitoring systems. This research explores the development of optimized probabilistic graphic models for the discretization thresholds of alarm system predictor variables. The study presents a statistical model framework that increases the efficacy of fire detection by predicting the discretization thresholds of alarm system predictor variable fluctuations used to detect the onset of fire. The work applies the Bayesian networks and probabilistic visual models to reveal the specific characteristics required to cope with fire detection strategies and patterns. The adopted methodology utilizes a combination of prior knowledge and statistical data to draw conclusions from observations. Utilizing domain knowledge to compute conditional dependencies between network variables enabled predictions to be made through the application of specialized analytical and simulation techniques. 展开更多
关键词 Neural Network DISCRETIZATION Alarm systems Graphical models Machine Learning
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Semantic model and optimization of creative processes at mathematical knowledge formation
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作者 Victor Egorovitch Firstov 《Natural Science》 2010年第8期915-922,共8页
The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the ... The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications. 展开更多
关键词 the Cybernetic Conception Optimization of CONTROL Quantitative and Qualitative Information Measures modelling Intellectual systems Neural Network MAtheMATICAL Education the CONTROL of Pedagogical PROCESSES CREATIVE Pedagogics Cognitive and CREATIVE PROCESSES Informal Axiomatic thery SEMANTIC NET NET Optimization Parameters the Topology of SEMANTIC NET Metrization the System of Coverings Stochastic model of CREATIVE PROCESSES At the Formation of MAtheMATICAL Knowledge Branching Markovian Process Great Main Points Strategy (GMP-Strategy) of the CREATIVE PROCESSES CONTROL Interdisciplinary Learning: Colorimetric Barycenter
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On the Community Correction Model of the State and Domain Jurisprudence
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作者 Si Haojie 《学术界》 CSSCI 北大核心 2014年第10期263-267,共5页
The"state and domain phenomenon"emerged at the modeling period of the crowd system,and with the development of cities,communities are extruded by the multivariate space and the crowd system,forming the socia... The"state and domain phenomenon"emerged at the modeling period of the crowd system,and with the development of cities,communities are extruded by the multivariate space and the crowd system,forming the social need of a basic guarantee of community correction. After the expansion of communities,the functional integration period begins,which leads to the period of urban transition,when community and the jurisprudential basis begin to coincide with each other,bringing the community correction model. In the industrialized period,the urban population made great contribution to the community correction of cities. Fromthe perspective of globalization,urban integration will experience the anguish of community correction,and crime and punishment will enter communities of the whole society,forming normal community correction model,so the service systemof community correction begins with the formation of the community-based management system,the crowd-based management range,the fundamental organization structure and the coincidence of the organizing function. 展开更多
关键词 社区 矫正 域名 社会需求 城市转型 挤出系统 管理系统 组织结构
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The Integration of Network Teaching and Chinese Art History Education in Colleges
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作者 Tiantian Hou 《Journal of Contemporary Educational Research》 2021年第5期47-50,共4页
Based on the network teaching model,this article briefly summarizes the development of Chinese art history education in universities,analyzes the importance of integrating network teaching in Chinese art history lesso... Based on the network teaching model,this article briefly summarizes the development of Chinese art history education in universities,analyzes the importance of integrating network teaching in Chinese art history lessons,and explores the integration strategy. 展开更多
关键词 Network teaching model Colleges and universities Chinese art history teaching integration strategy
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The Fuzzy Modeling Algorithm for Complex Systems Based on Stochastic Neural Network
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作者 李波 张世英 李银惠 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2002年第3期46-51,共6页
A fuzzy modeling method for complex systems is studied. The notation of general stochastic neural network (GSNN) is presented and a new modeling method is given based on the combination of the modified Takagi and Suge... A fuzzy modeling method for complex systems is studied. The notation of general stochastic neural network (GSNN) is presented and a new modeling method is given based on the combination of the modified Takagi and Sugeno's (MTS) fuzzy model and one-order GSNN. Using expectation-maximization(EM) algorithm, parameter estimation and model selection procedures are given. It avoids the shortcomings brought by other methods such as BP algorithm, when the number of parameters is large, BP algorithm is still difficult to apply directly without fine tuning and subjective tinkering. Finally, the simulated example demonstrates the effectiveness. 展开更多
关键词 Complex system modeling General stochastic neural network MTS fuzzy model Expectation-maximization algorithm
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Mechatronic Modeling and Domain Transformation of Multi-physics Systems
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作者 Clarence W.DE SILVA 《Instrumentation》 2021年第1期14-28,共15页
The enhanced definition of Mechatronics involves the four underlying characteristics of integrated,unified,unique,and systematic approaches.In this realm,Mechatronics is not limited to electro-mechanical systems,in th... The enhanced definition of Mechatronics involves the four underlying characteristics of integrated,unified,unique,and systematic approaches.In this realm,Mechatronics is not limited to electro-mechanical systems,in the multi-physics sense,but involves other physical domains such as fluid and thermal.This paper summarizes the mechatronic approach to modeling.Linear graphs facilitate the development of state-space models of mechatronic systems,through this approach.The use of linear graphs in mechatronic modeling is outlined and an illustrative example of sound system modeling is given.Both time-domain and frequency-domain approaches are presented for the use of linear graphs.A mechatronic model of a multi-physics system may be simplified by converting all the physical domains into an equivalent single-domain system that is entirely in the output domain of the system.This approach of converting(transforming)physical domains is presented.An illustrative example of a pressure-controlled hydraulic actuator system that operates a mechanical load is given. 展开更多
关键词 Mechatronic modeling Multi-physics systems Integrated Unified Unique and Systematic Approach Linear Graphs Physical Domain Conversion/Transformation
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Research on the Propagation Models and Defense Techniques of Internet Worms
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作者 Tian-Yun Huang 《Journal of Electronic Science and Technology of China》 2008年第1期32-38,共7页
Internet worm is harmful to network security,and it has become a research hotspot in recent years.A thorough survey on the propagation models and defense techniques of Internet worm is made in this paper.We first give... Internet worm is harmful to network security,and it has become a research hotspot in recent years.A thorough survey on the propagation models and defense techniques of Internet worm is made in this paper.We first give its strict definition and discuss the working mechanism.We then analyze and compare some repre-sentative worm propagation models proposed in recent years,such as K-M model,two-factor model,worm-anti-worm model(WAW),firewall-based model,quarantine-based model and hybrid benign worm-based model,etc.Some typical defense techniques such as virtual honeypot,active worm prevention and agent-oriented worm defense,etc.,are also discussed.The future direction of the worm defense system is pointed out. 展开更多
关键词 Defense system Internet worm network security propagation model
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THE MODEL VALIDATION OF DYNAMIC NEURAL NETWORKS
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作者 李秀娟 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期185-189,共5页
This paper investigates the problem of the model validation in identifying discrete-time-nonlinear dynamic systems by using neural networks with a single hidden layer.Based on the estimation theory,a synthetic error-i... This paper investigates the problem of the model validation in identifying discrete-time-nonlinear dynamic systems by using neural networks with a single hidden layer.Based on the estimation theory,a synthetic error-index(SEI)criterion for the neural network models has been developed.By using the powerful training algorithm of recursive prediction error (RPE),two simulated non-linear systems are studied,and the results show that the synthetic error-index criterion can be used to verify the dynamic neural network models.Furthermore,the proposed technique is much simple in calculation than that of the effective correlation tests.Finally,some problems required by further study are discussed. 展开更多
关键词 neural networks dynamic models non-linear systems odel validation system identification
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Uniformed model of networked control systems with long time delay 被引量:4
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作者 Zhu Qixin Liu Hongli Hu Shousong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第2期385-390,共6页
Feedback control systems wherein the control loops are closed through a real-time network are called networked control systems (NCS). The defining feature of an NCS is that information is exchanged using a network a... Feedback control systems wherein the control loops are closed through a real-time network are called networked control systems (NCS). The defining feature of an NCS is that information is exchanged using a network among control system components. Two new concepts including long time delay and short time delay are proposed. The sensor is almost always clock driven. The controller or the actuator is either clock driven or event driven. Four possible driving modes of networked control systems are presented. The open loop mathematic models of networked control systems with long time delay are developed when the system is driven by anyone of the four different modes. The uniformed modeling method of networked control systems with long time delay is proposed. The simulation results are given in the end. 展开更多
关键词 networked control systems time delay model driving mode.
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Understanding roof deformation mechanics and parametric sensitivities of coal mine entries using the discrete element method 被引量:11
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作者 Rami Abousleiman Gabriel Walton Sankhaneel Sinha 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第1期123-129,共7页
Although conventional coal mine designs are conservative regarding pillar strength,local failures such as roof-falls and pillar bursts still affect mine safety and operations.Previous studies have identified that disc... Although conventional coal mine designs are conservative regarding pillar strength,local failures such as roof-falls and pillar bursts still affect mine safety and operations.Previous studies have identified that discontinuous,layered roof materials have some self-supporting capacity.This research is a preliminary step towards understanding these mechanics in coal-measure rocks.Although others have considered broad conceptual models and simplified analogs for mine roof behavior,this study presents a unique numerical model that more completely represents in-situ roof conditions.The discrete element method(DEM)is utilized to conduct a parametric analysis considering a range of in-situ stress ratios,material properties,and joint networks to determine the parameters controlling the stability of single-entries modeled in two-dimensions.Model results are compared to empirical observations of roof-support effectiveness(ARBS)in the context of the coal mine roof rating(CMRR)system.Results such as immediate roof displacement,overall stability,and statistical relationships between model parameters and outcomes are presented herein.Potential practical applications of this line of research include:(1)roof-support optimization for a range of coal-measure rocks,(2)establishment of a relationship between roof stability and pillar stress,and(3)determination of which parameters are most critical to roof stability and therefore require concentrated evaluation. 展开更多
关键词 Numerical modeling DISCRETE element method Coal mine ROOF rating ANALYSIS of ROOF bolt systems Sensitivity ANALYSIS Strain SOFTENING ubiquitous joints DISCRETE fracture network
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Resilience Against Replay Attacks:A Distributed Model Predictive Control Scheme for Networked Multi-Agent Systems 被引量:5
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作者 Giuseppe Franzè Francesco Tedesco Domenico Famularo 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第3期628-640,共13页
In this paper,a resilient distributed control scheme against replay attacks for multi-agent networked systems subject to input and state constraints is proposed.The methodological starting point relies on a smart use ... In this paper,a resilient distributed control scheme against replay attacks for multi-agent networked systems subject to input and state constraints is proposed.The methodological starting point relies on a smart use of predictive arguments with a twofold aim:1)Promptly detect malicious agent behaviors affecting normal system operations;2)Apply specific control actions,based on predictive ideas,for mitigating as much as possible undesirable domino effects resulting from adversary operations.Specifically,the multi-agent system is topologically described by a leader-follower digraph characterized by a unique leader and set-theoretic receding horizon control ideas are exploited to develop a distributed algorithm capable to instantaneously recognize the attacked agent.Finally,numerical simulations are carried out to show benefits and effectiveness of the proposed approach. 展开更多
关键词 Distributed model predictive control leader-follower networks multi-agent systems replay attacks resilient control
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t/k-fault diagnosis algorithm of n-dimensional hypercube network based on the MM*model 被引量:4
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作者 LIANG Jiarong ZHOU Ning YUN Long 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第1期216-222,共7页
Compared with accurate diagnosis, the system’s selfdiagnosing capability can be greatly increased through the t/kdiagnosis strategy at most k vertexes to be mistakenly identified as faulty under the comparison model,... Compared with accurate diagnosis, the system’s selfdiagnosing capability can be greatly increased through the t/kdiagnosis strategy at most k vertexes to be mistakenly identified as faulty under the comparison model, where k is typically a small number. Based on the Preparata, Metze, and Chien(PMC)model, the n-dimensional hypercube network is proved to be t/kdiagnosable. In this paper, based on the Maeng and Malek(MM)*model, a novel t/k-fault diagnosis(1≤k≤4) algorithm of ndimensional hypercube, called t/k-MM*-DIAG, is proposed to isolate all faulty processors within the set of nodes, among which the number of fault-free nodes identified wrongly as faulty is at most k. The time complexity in our algorithm is only O(2~n n~2). 展开更多
关键词 hypercube network t/k-diagnosis algorithm multiprocessor systems the Maeng and Malek(MM)* model Preparata Metze and Chien(PMC)
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Design and Analysis of Integrated Predictive Iterative Learning Control for Batch Process Based on Two-dimensional System Theory 被引量:3
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作者 陈宸 熊智华 钟宜生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期762-768,共7页
Based on the two-dimensional (2D) system theory, an integrated predictive iterative learning control (2D-IPILC) strategy for batch processes is presented. First, the output response and the error transition model ... Based on the two-dimensional (2D) system theory, an integrated predictive iterative learning control (2D-IPILC) strategy for batch processes is presented. First, the output response and the error transition model predictions along the batch index can be calculated analytically due to the 2D Roesser model of the batch process. Then, an integrated framework of combining iterative learning control (ILC) and model predictive control (MPC) is formed reasonably. The output of feedforward ILC is estimated on the basis of the predefined process 2D model. By min- imizing a quadratic objective function, the feedback MPC is introduced to obtain better control performance for tracking problem of batch processes. Simulations on a typical batch reactor demonstrate that the satisfactory tracking performance as well as faster convergence speed can be achieved than traditional proportion type (P- t-we) ILC despite the model error and disturbances. 展开更多
关键词 lterative learning control model predictive control Integrated control Batch process Two-dimensional systems
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Systems biology approaches for studying the pathogenesis of non-alcoholic fatty liver disease 被引量:2
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作者 Ciarán P Fisher Andrzej M Kierzek +1 位作者 Nick J Plant J Bernadette Moore 《World Journal of Gastroenterology》 SCIE CAS 2014年第41期15070-15078,共9页
Non-alcoholic fatty liver disease (NAFLD) is a progressive disease of increasing public health concern. In western populations the disease has an estimated prevalence of 20%-40%, rising to 70%-90% in obese and type II... Non-alcoholic fatty liver disease (NAFLD) is a progressive disease of increasing public health concern. In western populations the disease has an estimated prevalence of 20%-40%, rising to 70%-90% in obese and type II diabetic individuals. Simplistically, NAFLD is the macroscopic accumulation of lipid in the liver, and is viewed as the hepatic manifestation of the metabolic syndrome. However, the molecular mechanisms mediating both the initial development of steatosis and its progression through non-alcoholic steatohepatitis to debilitating and potentially fatal fibrosis and cirrhosis are only partially understood. Despite increased research in this field, the development of non-invasive clinical diagnostic tools and the discovery of novel therapeutic targets has been frustratingly slow. We note that, to date, NAFLD research has been dominated by in vivo experiments in animal models and human clinical studies. Systems biology tools and novel computational simulation techniques allow the study of large-scale metabolic networks and the impact of their dysregulation on health. Here we review current systems biology tools and discuss the benefits to their application to the study of NAFLD. We propose that a systems approach utilising novel in silico modelling and simulation techniques is key to a more comprehensive, better targeted NAFLD research strategy. Such an approach will accelerate the progress of research and vital translation into clinic. 展开更多
关键词 Non-alcoholic fatty liver disease Network METABOLISM systems biology modelling Regulation Simulation
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