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Analysis of the Current Situation of Cost Management and Control of Highway Construction Projects
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作者 Pei Liu 《Journal of Architectural Research and Development》 2024年第5期30-35,共6页
The highway engineering process is complex,coupled with a relatively long construction period,hence requires increased coordination between participating units to prevent economic disputes and efficiency losses.The ma... The highway engineering process is complex,coupled with a relatively long construction period,hence requires increased coordination between participating units to prevent economic disputes and efficiency losses.The main body of the construction project needs to strengthen the management and control of funds.In this regard,this paper analyzes the importance of cost management in highway projects by clarifying and analyzing the current cost management status quo problems and causes.The highway engineering cost control strategy and implementation methods are summarized to provide references for improving the quality of highway engineering. 展开更多
关键词 Highway engineering cost management Management status cost control
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Cost Management and Cost Control of Photovoltaic Projects
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作者 Weimin Lv 《Journal of Architectural Research and Development》 2024年第4期63-70,共8页
With the rapid development of the photovoltaic(PV)industry and policy support,photovoltaic engineering has attracted much attention as a clean energy project.However,the complexity and huge investment scale of photovo... With the rapid development of the photovoltaic(PV)industry and policy support,photovoltaic engineering has attracted much attention as a clean energy project.However,the complexity and huge investment scale of photovoltaic projects make cost management and cost control the key to project success.The purpose of this paper is to discuss the cost management and cost control strategies of photovoltaic projects,analyze their importance and challenges in the process of project implementation,and discuss the common cost control methods and techniques in photovoltaic projects,to improve cost management and cost control in photovoltaic projects,and to provide a reference for the sustainable development of the industry. 展开更多
关键词 Photovoltaic engineering cost management cost control
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Discussion on Cost Budgeting and Cost Control Strategies for Prefabricated Construction Projects
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作者 Congzi Cheng 《Journal of Architectural Research and Development》 2024年第4期17-23,共7页
In the process of China’s national economic development,the construction industry is a very important component and has a direct impact on the level of China’s economic construction.Nowadays,the development speed of... In the process of China’s national economic development,the construction industry is a very important component and has a direct impact on the level of China’s economic construction.Nowadays,the development speed of the prefabricated construction industry is constantly accelerating.To effectively ensure the economic benefits of engineering projects,it is necessary to comprehensively strengthen cost budgeting and cost control.This article analyzes the cost budget of prefabricated construction projects,introduces the application advantages of prefabricated construction,and proposes specific cost budgeting and cost control measures,hoping to provide some reference for relevant researchers. 展开更多
关键词 Prefabricated building Engineering cost budget cost control
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Construction Cost Control Strategy of Finished House Based on BIM-5D
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作者 Dongchun Xia Xinyue Zhou 《Journal of World Architecture》 2024年第4期15-20,共6页
Building Information Modeling(BIM)technology can not only achieve project refinement management of the construction process based on a 3D model but also form a BIM-5D model based on the fusion of progress data and cos... Building Information Modeling(BIM)technology can not only achieve project refinement management of the construction process based on a 3D model but also form a BIM-5D model based on the fusion of progress data and cost data to achieve the dynamic control of the whole process of project cost.This paper discusses the application of BIM-5D in the cost control of finished house construction,aiming to provide technical reference for China’s finished house project units,so that they can master how to realize the construction of cost control system based on BIM,the monitoring of the key coefficients of the cost,corrective action,to ensure that the project cost deviation is within the controllable range,and to make an effective guarantee for the economic benefits of the project construction. 展开更多
关键词 BIM-5D Finished house project cost control system cost corrective deviation
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Cost control for real estate development projects in China - Part 1: Literature review
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作者 夏煦 《Journal of Chongqing University》 CAS 2014年第2期54-61,共8页
The background and purpose, and the current situation of the cost control theory of real estate development project are disscussed in the paper. Problems of cost control for real estate development projects in China a... The background and purpose, and the current situation of the cost control theory of real estate development project are disscussed in the paper. Problems of cost control for real estate development projects in China are analyzed and summarized. According to the real estate development project cost control problems and related factors, a cost control index system of real estate development enterprise, and a cost control factors index system of real estate projects are constructed respectively. Cost control in the five stages of a real estate development project is introduced and summarized respectively. The five stages include: the investment decision-making, planning and design stage, the bidding phase, project implementation stage, and rental or sale. 展开更多
关键词 real estate cost control index system cost control factors cost control method
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Cost Control Strategies for Hubei General Highway Greening Project
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作者 ZHANG Qian HUANG Yaojun AN Yunhua 《Journal of Landscape Research》 2024年第4期17-20,共4页
In order to respond to the national policy of focusing on the service of building a new development pattern and promoting high-quality development,and to reduce the cost of greening projects while ensuring the effect ... In order to respond to the national policy of focusing on the service of building a new development pattern and promoting high-quality development,and to reduce the cost of greening projects while ensuring the effect of highway landscape,a process and cost control points of highway greening design,construction,and maintenance are summarized through a review of the literature.Additionally,this paper examines the attributes of highway greening and proposes cost control strategies that are aligned with these attributes.It is proposed that the implementation of cost control strategies for highway greening should commence at the project establishment phase,with the objective of establishing a comprehensive and effective cost management control system.While guaranteeing the greening landscape effect and the duration of the project,it is essential to regulate the crucial nodes in each phase of the design,construction,and maintenance process.Furthermore,it is vital to facilitate close collaboration between all parties involved,thereby reducing costs,conserving resources,and lowering energy consumption.This approach can also lead to enhanced economic and social benefits for highway greening projects. 展开更多
关键词 General highway Highway greening Greening project cost control
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Cost Control Strategies in the Pre-Construction Period of Highway Construction
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作者 Chunbo Chen 《Journal of Architectural Research and Development》 2024年第3期104-109,共6页
Effective cost control in the investment and design phases of highway construction is crucial for managing project expenses.However,current management practices often overlook pre-construction cost management,leading ... Effective cost control in the investment and design phases of highway construction is crucial for managing project expenses.However,current management practices often overlook pre-construction cost management,leading to budget overruns and project delays during later stages.To ensure the smooth execution and cost control of highway construction projects,this paper examines the significance of cost control,evaluates the current state and challenges of highway construction,and proposes strategies for cost management.These strategies aim to establish a robust foundation for cost management in highway projects. 展开更多
关键词 Highway construction Preliminary management cost control Contract management Investment estimate
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Guaranteed Cost Active Fault-tolerant Control of Networked Control System with Packet Dropout and Transmission Delay 被引量:5
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作者 Xiao-Yuan Luo Mei-Jie Shang +1 位作者 Cai-Lian Chen Xin-Ping Guan 《International Journal of Automation and computing》 EI 2010年第4期509-515,共7页
The problem of guaranteed cost active fault-tolerant controller (AFTC) design for networked control systems (NCSs) with both packet dropout and transmission delay is studied in this paper. Considering the packet d... The problem of guaranteed cost active fault-tolerant controller (AFTC) design for networked control systems (NCSs) with both packet dropout and transmission delay is studied in this paper. Considering the packet dropout and transmission delay, a piecewise constant controller is adopted. With a guaranteed cost function, optimal controllers whose number is equal to the number of actuators are designed, and the design process is formulated as a convex optimal problem that can be solved by existing software. The control strategy is proposed as follows: when actuator failures appear, the fault detection and isolation unit sends out the information to the controller choosing strategy, and then the optimal stabilizing controller with the smallest guaranteed cost value is chosen. Two illustrative examples are given to demonstrate the effectiveness of the proposed approach. By comparing with the existing methods, it can be seen that our method has a better performance. 展开更多
关键词 Networked control system (NCS) packet dropout transmission delay active fault-tolerant control (AFTC) guaranteed cost controller.
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Energy-Efficient Optimal Guaranteed Cost Intermittent-Switch Control of a Direct Expansion Air Conditioning System 被引量:1
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作者 Jun Mei Zhenyu Lu +1 位作者 Junhao Hu Yuling Fan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第11期1852-1866,共15页
To improve the energy efficiency of a direct expansion air conditioning(DX A/C) system while guaranteeing occupancy comfort, a hierarchical controller for a DX A/C system with uncertain parameters is proposed. The con... To improve the energy efficiency of a direct expansion air conditioning(DX A/C) system while guaranteeing occupancy comfort, a hierarchical controller for a DX A/C system with uncertain parameters is proposed. The control strategy consists of an open loop optimization controller and a closed-loop guaranteed cost periodically intermittent-switch controller(GCPISC). The error dynamics system of the closed-loop control is modelled based on the GCPISC principle. The difference,compared to the previous DX A/C system control methods, is that the controller designed in this paper performs control at discrete times. For the ease of designing the controller, a series of matrix inequalities are derived to be the sufficient conditions of the lower-layer closed-loop GCPISC controller. In this way, the DX A/C system output is derived to follow the optimal references obtained through the upper-layer open loop controller in exponential time, and the energy efficiency of the system is improved. Moreover, a static optimization problem is addressed for obtaining an optimal GCPISC law to ensure a minimum upper bound on the DX A/C system performance considering energy efficiency and output tracking error. The advantages of the designed hierarchical controller for a DX A/C system with uncertain parameters are demonstrated through some simulation results. 展开更多
关键词 Energy efficiency hierarchical control open loop optimal control optimal guaranteed cost periodically intermittent-switch control
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Social Cost Analysis of Biological Control Technology for Crop Diseases and Insect Pests
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作者 Jie XIE Lingling XIAO +4 位作者 Jinyu ZHAO Shoumei WAN Jian TANG Xiaolei JI Jing PENG 《Asian Agricultural Research》 2024年第8期14-16,共3页
With the rapid development of modern agriculture,the prevention and control of crop diseases and insect pests has become an important part to ensure the safety of agricultural production,the quality of agricultural pr... With the rapid development of modern agriculture,the prevention and control of crop diseases and insect pests has become an important part to ensure the safety of agricultural production,the quality of agricultural products and the safety of agricultural ecological environment.Although the effect of traditional chemical prevention and control technology is remarkable,the health risks and environmental problems brought by it should not be ignored.As a green and environmentally friendly means of prevention and control,biological prevention and control technology has gradually become a hot research topic and a trend of agricultural production.This paper is intended to comprehensively evaluate the social costs of biological control technologies for crop diseases and pests,including the health risks reduced,environmental improvements,economic benefits,and barriers to promotion,and put forward corresponding policy recommendations. 展开更多
关键词 CROPS DISEASES and INSECT PESTS BIOLOGICAL control SOCIAL cost
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Standard Costing and Cost Control in Nigerian Oil and Gas Industry
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作者 Cletus O. Akenbor Thankgod C. Agwor 《Journal of Modern Accounting and Auditing》 2015年第4期185-193,共9页
The purpose of this study was to investigate the relationship between standard costing and cost control in Nigerian oil and gas industry. This was achieved through a review of extant literature and development of hypo... The purpose of this study was to investigate the relationship between standard costing and cost control in Nigerian oil and gas industry. This was achieved through a review of extant literature and development of hypotheses. The population for the study consisted of petroleum marketing companies listed in the Nigerian Stock Exchange Factbook of 2012. In order to generate the necessary data for this study, both primary and secondary methods of data collection were adopted. The primary data were collected through the administration of a questionnaire designed in a 5-point Likert scale, while the secondary data were sourced from the Nigerian Stock Exchange Factbook of 2011. The findings generated in this study revealed that a significant relationship exists between standard costing and cost control. It was observed that the more a firm practices standard costing, the more efficient is the firm in material, labor, and overhead costs. Based on the above findings, we recommended that oil and gas finns in Nigeria should adopt and apply standard costing in their accounting system so as to ensure the efficient use of resources for an effective control of costs. 展开更多
关键词 standard costing cost control variance actual cost
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Mining cost analysis and cost control based on the sensitivity factor analysis
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作者 ZHAO Shun-di KONG Yu-sheng LU Min 《Journal of Modern Accounting and Auditing》 2007年第11期44-49,共6页
This paper systematically generalizes relevant theories and methods regarding mining cost control and constitutes the model for the mining cost analysis. It also comes up with the sensitivity factor analysis to conduc... This paper systematically generalizes relevant theories and methods regarding mining cost control and constitutes the model for the mining cost analysis. It also comes up with the sensitivity factor analysis to conduct mining cost control. The theories and methods have been experimented with Jiangsu Chuanshan Mining Joint-Stock Company Ltd. Case studies have been undertaken on mining cost of the company and the most sensitive factor which affects mining cost has been found accordingly. Finally the paper concludes that the focus concerning the cost control of the company should be directed at output and material costs. 展开更多
关键词 mining cost cost analysis cost control
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Research on Procurement Cost Control Based on Supply Chain Management
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作者 Lixia Liu Wenting Shao 《Proceedings of Business and Economic Studies》 2024年第5期106-111,共6页
In modern enterprise management,strengthening the control and management of procurement processes can effectively reduce operational costs.However,with the continuous reform and improvement of China’s market economy ... In modern enterprise management,strengthening the control and management of procurement processes can effectively reduce operational costs.However,with the continuous reform and improvement of China’s market economy system,competition among supply chain enterprises has intensified.The traditional procurement management model is no longer able to meet the needs of enterprise development in the current era.As a result,procurement management based on supply chain management has emerged,offering significant improvements in the scientific management of procurement processes.It has become an important means of promoting the long-term development of enterprises.This paper primarily analyzes and studies procurement cost control based on supply chain management,providing insights for reference. 展开更多
关键词 Supply chain management Procurement cost control
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Robust Non-Fragile Guaranteed Cost Control for Nonlinear Time Delay Discrete-Time Systems Based on T-S Model
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作者 Yu-Ping Zhang Hong Zhu Shou-Ming Zhong 《Journal of Electronic Science and Technology of China》 2007年第2期153-158,共6页
This paper concerns the robust non-fragile guaranteed cost control for nonlinear time delay discrete-time systems based on Takagi-Sugeno (T-S) model. The problem is to design a guaranteed cost state feedback control... This paper concerns the robust non-fragile guaranteed cost control for nonlinear time delay discrete-time systems based on Takagi-Sugeno (T-S) model. The problem is to design a guaranteed cost state feedback controller which can tolerate uncertainties from both models and gain variation. Sufficient conditions for the existence of such controller are given based on the linear matrix inequality (LMI) approach combined with Lyapunov method and inequality technique. A numerical example is given to illustrate the feasibility and effectiveness of our result. 展开更多
关键词 Guaranteed cost control linear matrix Inequality non-fragil e control robust control T-S model.
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Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints
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作者 Qian Ma Peng Jin Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第6期1447-1457,共11页
In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is studied.First,an augmented system is constructed by the tracking error system a... In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is studied.First,an augmented system is constructed by the tracking error system and reference system.This transformation aims to convert the tracking control prob-lem into a stabilization control problem.Then,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty items.Based on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is developed.Finally,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal controller.The proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety constraints.The performance of the algorithm is evaluated by the numerical simulation. 展开更多
关键词 Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.
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Robust reliable guaranteed cost control for uncertain singular systems with time-delay 被引量:4
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作者 Qixun Lan Yuxiao Liu +1 位作者 Huawei Niu Jiarong Liang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第1期110-117,共8页
The robust reliable guaranteed cost control for uncertain singular delay systems with actuator failures and a given quadratic cost function is studied. The system under consideration involves constant time-delay and n... The robust reliable guaranteed cost control for uncertain singular delay systems with actuator failures and a given quadratic cost function is studied. The system under consideration involves constant time-delay and norm-bounded parameter uncertainties. The purpose is to design state feedback controllers which can tolerate actuator failure, such that the closed-loop system is stable, and the specified cost function has an upper bound for all admissible uncertainties. The sufficient conditions for the solvability of this problem are obtained by a linear matrix inequality (LMI) method. Furthermore, a numerical example is given to demonstrate the applicability of the proposed approach. 展开更多
关键词 singular system reliable control guaranteed cost control actuator failure linear matrix inequality time-delay.
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Non-fragile guaranteed cost control of discrete-time fuzzy bilinear system 被引量:5
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作者 Guo Zhang Junmin Li 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期629-634,共6页
This paper focuses on the problem of non-fragile guaranteed cost control for a class of T-S discrete-time fuzzy bilinear systems(DFBS).Based on the parallel distributed compensation(PDC) approach,the sufficient co... This paper focuses on the problem of non-fragile guaranteed cost control for a class of T-S discrete-time fuzzy bilinear systems(DFBS).Based on the parallel distributed compensation(PDC) approach,the sufficient conditions are derived such that the closed-loop system is asymptotically stable and the cost function value is no more than a certain upper bound in the presence of the additive controller gain perturbations.The non-fragile guaranteed cost controller can be obtained by solving a set of bilinear matrix inequalities(BMIs).The Van de Vusse model is utilized to demonstrate the validity and effectiveness of the proposed approach. 展开更多
关键词 discrete-time fuzzy bilinear system(DFBS) nonfragile control guaranteed cost control bilinear matrix inequality(BMI).
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Nonfragile guaranteed cost control for Delta operator-formulated uncertain time-delay systems 被引量:2
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作者 Ruiquan LIN, Silian CHEN, Xuwei DING (College of Electrical Engineering and Automation, Fuzhou University, Fuzhou Fujian 350108, China) 《控制理论与应用(英文版)》 EI 2010年第2期233-238,共6页
With consideration that the controller parameters may vary from the designed value when the controller is realized, based on Lyapunov stability theory, a design method of nonfragile guaranteed cost control for a class... With consideration that the controller parameters may vary from the designed value when the controller is realized, based on Lyapunov stability theory, a design method of nonfragile guaranteed cost control for a class of Delta operator-formulated uncertain time-delay systems is studied. A sufficient condition for the existence of the nonfragile guaranteed cost controller is given. A numeric example is then given to illustrate the effectiveness and the feasibility of the designed method. The results show that even if the parameters of the designed controller are of variations, the closed-loop system is still asymptotically stable and the super value of the cost function can also be obtained, while the closed-loop system will be unstable if the variations of the controller parameters are not considered when the controller is designed. The nonfragile guaranteed cost controller derived from the traditional shift operator method may cause the closed-loop system to be unstable, while the nonfragile guaranteed cost controller based on Delta operator method can avoid the unstable problem of the closed-loop system. 展开更多
关键词 Delta operator Time-delay system Nonfragile control Guaranteed cost control LMI
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An LMI Method to Robust Iterative Learning Fault-tolerant Guaranteed Cost Control for Batch Processes 被引量:11
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作者 王立敏 陈曦 高福荣 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期401-411,共11页
Based on an equivalent two-dimensional Fornasini-Marchsini model for a batch process in industry, a closed-loop robust iterative learning fault-tolerant guaranteed cost control scheme is proposed for batch processes w... Based on an equivalent two-dimensional Fornasini-Marchsini model for a batch process in industry, a closed-loop robust iterative learning fault-tolerant guaranteed cost control scheme is proposed for batch processes with actuator failures. This paper introduces relevant concepts of the fault-tolerant guaranteed cost control and formulates the robust iterative learning reliable guaranteed cost controller (ILRGCC). A significant advantage is that the proposed ILRGCC design method can be used for on-line optimization against batch-to-batch process uncertainties to realize robust tracking of set-point trajectory in time and batch-to-batch sequences. For the convenience of implementation, only measured output errors of current and previous cycles are used to design a synthetic controller for iterative learning control, consisting of dynamic output feedback plus feed-forward control. The proposed controller can not only guarantee the closed-loop convergency along time and cycle sequences but also satisfy the H∞performance level and a cost function with upper bounds for all admissible uncertainties and any actuator failures. Sufficient conditions for the controller solution are derived in terms of linear matrix inequalities (LMIs), and design procedures, which formulate a convex optimization problem with LMI constraints, are presented. An example of injection molding is given to illustrate the effectiveness and advantages of the ILRGCC design approach. 展开更多
关键词 two-dimensional Fornasini-Marchsini model batch process iterative learning control linear matrix inequality fault-tolerant guaranteed cost control
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Event-triggered robust guaranteed cost control for two-dimensional nonlinear discrete-time systems 被引量:2
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作者 WANG Sen BU Xuhui LIANG Jiaqi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1243-1251,共9页
An event-triggered scheme is proposed to solve the problems of robust guaranteed cost control for a class of two-dimensional(2-D)discrete-time systems.Firstly,an eventtriggered scheme is proposed for 2-D discrete-time... An event-triggered scheme is proposed to solve the problems of robust guaranteed cost control for a class of two-dimensional(2-D)discrete-time systems.Firstly,an eventtriggered scheme is proposed for 2-D discrete-time systems with parameter uncertainties and sector nonlinearities.Then,according to the Lyapunov functional method,the sufficient conditions for the existence of event-triggered robust guaranteed cost controller for 2-D discrete-time systems with parameter uncertainties and sector nonlinearities are given.Furthermore,based on the sufficient conditions and the linear matrix inequality(LMI)technique,the problem of designing event-triggered robust guaranteed cost controller is transformed into a feasible solution problem of LMI.Finally,a numerical example is given to demonstrate that,under the proposed event-triggered robust guaranteed cost control,the closed-loop system is asymptotically stable and fewer communication resources are occupied. 展开更多
关键词 event-triggered robust guaranteed cost control two dimensional(2-D)nonlinear system networked control system.
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