期刊文献+
共找到21,177篇文章
< 1 2 250 >
每页显示 20 50 100
Contract Mechanism of Water Environment Regulation for Small and Medium Sized Enterprises Based on Optimal Control Theory
1
作者 Shuang Zhao Hongbin Gu +2 位作者 Lianfang Xue Dongsheng Wang Bin Huang 《Journal of Water Resource and Protection》 CAS 2024年第7期538-556,共20页
The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of trea... The small and scattered enterprise pattern in the county economy has formed numerous sporadic pollution sources, hindering the centralized treatment of the water environment, increasing the cost and difficulty of treatment. How enterprises can make reasonable decisions on their water environment behavior based on the external environment and their own factors is of great significance for scientifically and effectively designing water environment regulation mechanisms. Based on optimal control theory, this study investigates the design of contractual mechanisms for water environmental regulation for small and medium-sized enterprises. The enterprise is regarded as an independent economic entity that can adopt optimal control strategies to maximize its own interests. Based on the participation of multiple subjects including the government, enterprises, and the public, an optimal control strategy model for enterprises under contractual water environmental regulation is constructed using optimal control theory, and a method for calculating the amount of unit pollutant penalties is derived. The water pollutant treatment cost data of a paper company is selected to conduct empirical numerical analysis on the model. The results show that the increase in the probability of government regulation and public participation, as well as the decrease in local government protection for enterprises, can achieve the same regulatory effect while reducing the number of administrative penalties per unit. Finally, the implementation process of contractual water environmental regulation for small and medium-sized enterprises is designed. 展开更多
关键词 Optimal control Theory Small and Medium-Sized Enterprises Water Environment regulation Contract Mechanism
下载PDF
Frequency Regulation of Alternating Current Microgrid Based on Hierarchical Control Using Fuzzy Logic
2
作者 WU Xueyang SHAN Yinghao SHEN Bo 《Journal of Donghua University(English Edition)》 CAS 2024年第5期536-544,共9页
An alternating current(AC)microgrid is a system that integrates renewable power,power converters,controllers and loads.Hierarchical control can manage the frequency of the microgrid to prevent imbalance and collapse o... An alternating current(AC)microgrid is a system that integrates renewable power,power converters,controllers and loads.Hierarchical control can manage the frequency of the microgrid to prevent imbalance and collapse of the system.The existing frequency control methods use traditional proportion integration(PI)controllers,which cannot adjust PI parameters in real-time to respond to the status changes of the system.Hierarchical control driven by fuzzy logic allows real-time adjustment of the PI parameters and the method used a two-layer control structure.The primary control used droop control to adjust power distribution,and fuzzy logic was used in the voltage loop of the primary control.The secondary control was added to make up for frequency deviation caused by droop control,and fuzzy logic was used in the secondary frequency control to deal with the dynamic change of frequency caused by the disturbances of loads.The proposed method was simulated in Matlab/Simulink.In the primary control,the proposed method reduced the total harmonic distortion(THD)of two cycles of the output voltage from 4.19%to 3.89%;in the secondary control,the proposed method reduced the frequency fluctuation of the system by about 0.03 Hz and 0.04 Hz when the load was increased and decreased,respectively.The results show that the proposed methods have a better effect on frequency maintenance and voltage control of the AC microgrid. 展开更多
关键词 fuzzy logic hierarchical control frequency regulation droop control alternating current(AC)microgrid
下载PDF
Fractional Gradient Descent RBFNN for Active Fault-Tolerant Control of Plant Protection UAVs
3
作者 Lianghao Hua Jianfeng Zhang +1 位作者 Dejie Li Xiaobo Xi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2129-2157,共29页
With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rej... With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance. 展开更多
关键词 Radial basis function neural network plant protection unmanned aerial vehicle active disturbance rejection controller fractional gradient descent algorithm
下载PDF
Regulation on the Protection of Fossils Issued by the State Council of the People's Republic of China:Scientists' Researches Protected Legally—Further Explanation 被引量:1
4
作者 Hao Ziguo,Fei Hongcai and Liu Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第2期532-532,共1页
With large-scale engineering projects being carried out in China, a large number of fossil localities have been discovered and excavated by responsible agencies, but still some important fossils of great value have be... With large-scale engineering projects being carried out in China, a large number of fossil localities have been discovered and excavated by responsible agencies, but still some important fossils of great value have been removed and smuggled into foreign countries. In the last three years, more than 1345 fossil specimens have been intercepted by Customs in Shenzhen, Shanghai, Tianjin, Beijing and elsewhere, and more than 5000 fossils, most of which are listed as key fossils, 展开更多
关键词 Further Explanation regulation on the protection of Fossils Issued by the State Council of the People’s Republic of China Researches protected Legally
下载PDF
Histone demethylase JMJD3 downregulation protects against aberrant force-induced osteoarthritis through epigenetic control of NR4A1 被引量:2
5
作者 Yu Jin Zhen Liu +5 位作者 Zhenxia Li Hairui Li Cheng Zhu Ruomei Li Ting Zhou Bing Fang 《International Journal of Oral Science》 SCIE CAS CSCD 2022年第3期396-409,共14页
Osteoarthritis(OA)is a prevalent joint disease with no effective treatment strategies.Aberrant mechanical stimuli was demonstrated to be an essential factor for OA pathogenesis.Although multiple studies have detected ... Osteoarthritis(OA)is a prevalent joint disease with no effective treatment strategies.Aberrant mechanical stimuli was demonstrated to be an essential factor for OA pathogenesis.Although multiple studies have detected potential regulatory mechanisms underlying OA and have concentrated on developing novel treatment strategies,the epigenetic control of OA remains unclear.Histone demethylase JMJD3 has been reported to mediate multiple physiological and pathological processes,including cell differentiation,proliferation,autophagy,and apoptosis.However,the regulation of JMJD3 in aberrant force-related OA and its mediatory effect on disease progression are still unknown.In this work,we confirmed the upregulation of JMJD3 in aberrant forceinduced cartilage injury in vitro and in vivo.Functionally,inhibition of JMJD3 by its inhibitor,GSK-J4,or downregulation of JMJD3 by adenovirus infection of sh-JMJD3 could alleviate the aberrant force-induced chondrocyte injury.Mechanistic investigation illustrated that aberrant force induces JMJD3 expression and then demethylates H3K27me3 at the NR4A1 promoter to promote its expression.Further experiments indicated that NR4A1 can regulate chondrocyte apoptosis,cartilage degeneration,extracellular matrix degradation,and inflammatory responses.In vivo,anterior cruciate ligament transection(ACLT)was performed to construct an OA model,and the therapeutic effect of GSK-J4 was validated.More importantly,we adopted a peptide-si RNA nanoplatform to deliver si-JMJD3 into articular cartilage,and the severity of joint degeneration was remarkably mitigated.Taken together,our findings demonstrated that JMJD3 is flow-responsive and epigenetically regulates OA progression.Our work provides evidences for JMJD3 inhibition as an innovative epigenetic therapy approach for joint diseases by utilizing p5RHH-si RNA nanocomplexes. 展开更多
关键词 Histone demethylase JMJD3 downregulation protects against aberrant force-induced osteoarthritis through epigenetic control of NR4A1
下载PDF
Regulations for the Protection of the Right of Communication through Information Network
6
《中国专利与商标》 2006年第3期90-94,共5页
Article 1 These Regulations have been formulated under the Copyright Law of the People's Republic of China (hereinafter referred to as the Copyright Law) with a view to protecting the right of communication throug... Article 1 These Regulations have been formulated under the Copyright Law of the People's Republic of China (hereinafter referred to as the Copyright Law) with a view to protecting the right of communication through information network enjoyed by copyright owners, performers and producers of sound recordings and video recordings (hereinafter collectively referred to as the right owners) and to encouraging creation and communication of works conducive to the building of a socialist society that is advanced ethically and materially. 展开更多
关键词 regulations for the protection of the Right of Communication through Information Network
下载PDF
Technical Regulations for Comprehensive Control Weeding in Millet Field 被引量:1
7
作者 周新建 刘环 +3 位作者 魏志敏 袁淑红 侯升林 周汉章 《Agricultural Science & Technology》 CAS 2016年第10期2321-2323,2426,共4页
According to experiments in many years in Hebei Province, the research explored weed comprehensive control technology on millet fields in terms of application range, prevention rules, prevention object, agricultural c... According to experiments in many years in Hebei Province, the research explored weed comprehensive control technology on millet fields in terms of application range, prevention rules, prevention object, agricultural control, physical control, and chemical control and proposed specific methods and technological indices in order to provide technological references for comprehensive control on weeds of millet fields. 展开更多
关键词 MILLET WEED Comprehensive control Technical regulations
下载PDF
The future of artificial hibernation medicine:protection of nerves and organs after spinal cord injury 被引量:1
8
作者 Caiyun Liu Haixin Yu +4 位作者 Zhengchao Li Shulian Chen Xiaoyin Li Xuyi Chen Bo Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期22-28,共7页
Spinal cord injury is a serious disease of the central nervous system involving irreversible nerve injury and various organ system injuries.At present,no effective clinical treatment exists.As one of the artificial hi... Spinal cord injury is a serious disease of the central nervous system involving irreversible nerve injury and various organ system injuries.At present,no effective clinical treatment exists.As one of the artificial hibernation techniques,mild hypothermia has preliminarily confirmed its clinical effect on spinal cord injury.However,its technical defects and barriers,along with serious clinical side effects,restrict its clinical application for spinal cord injury.Artificial hibernation is a futureoriented disruptive technology for human life support.It involves endogenous hibernation inducers and hibernation-related central neuromodulation that activate particular neurons,reduce the central constant temperature setting point,disrupt the normal constant body temperature,make the body adapt"to the external cold environment,and reduce the physiological resistance to cold stimulation.Thus,studying the artificial hibernation mechanism may help develop new treatment strategies more suitable for clinical use than the cooling method of mild hypothermia technology.This review introduces artificial hibernation technologies,including mild hypothermia technology,hibernation inducers,and hibernation-related central neuromodulation technology.It summarizes the relevant research on hypothermia and hibernation for organ and nerve protection.These studies show that artificial hibernation technologies have therapeutic significance on nerve injury after spinal co rd injury through inflammatory inhibition,immunosuppression,oxidative defense,and possible central protection.It also promotes the repair and protection of res pirato ry and digestive,cardiovascular,locomoto r,urinary,and endocrine systems.This review provides new insights for the clinical treatment of nerve and multiple organ protection after spinal cord injury thanks to artificial hibernation.At present,artificial hibernation technology is not mature,and research fa ces various challenges.Neve rtheless,the effort is wo rthwhile for the future development of medicine. 展开更多
关键词 artificial hibernation central thermostatic-resista nt regulation hypothermia multi-system protection neuroprotection organ protection spinal cord injury synthetic torpor
下载PDF
Control design for the nonlinear benchmark problem via the output regulation method 被引量:4
9
作者 JieHUANG GuoqiangHU 《控制理论与应用(英文版)》 EI 2004年第1期11-19,共9页
The problem of designing a feedback controller to achieve asymptotic disturbance rejection / attenuation while maintaining good transient response in the RTAC system is known as a benchmark nonlinear control problem, ... The problem of designing a feedback controller to achieve asymptotic disturbance rejection / attenuation while maintaining good transient response in the RTAC system is known as a benchmark nonlinear control problem, which has been an intensive research subject since 1995. In this paper, we will further investigate the solvability of the robust disturbance rejection problem of the RTAC system by the measurement output feedback control based on the robust output regulation method. We have obtained a design by overcoming two major obstacles: find a closed-form solution of the regulator equations; and devise a nonlinear internal model to account for non-polynomial nonlinearities. 展开更多
关键词 RTAC system Robust control Nonlinear control Output regulation problem Disturbance rejection
下载PDF
Asymptotic regulation of cascade systems with unknown control directions and nonlinear parameterization 被引量:4
10
作者 Qiangde WANG Chunling WEI Yuqiang WU 《控制理论与应用(英文版)》 EI 2009年第1期51-56,共6页
A robust partial-state feedback asymptotic regulating control scheme is developed for a class of cascade systems with both nonlinear uncertainties and unknown control directions. A parameter separation technique is in... A robust partial-state feedback asymptotic regulating control scheme is developed for a class of cascade systems with both nonlinear uncertainties and unknown control directions. A parameter separation technique is introduced to separate the time-varying uncertainty and the unmeasurable state from nonlinear functions. Then, the Nussbaum-type gain method together with the idea of changing supply functions is adopted in the design of a smooth partial-state regulator that can ensure all the signals of the closed-loop system are globally uniformly bounded. Especially, the system state asymptotically converges to zero. The design procedure is illustrated through an example and the simulation results show that the controller is feasible and effective. 展开更多
关键词 Nonlinear systems Robust control Partial-state feedback Smooth regulator
下载PDF
Privacy Protection Based Access Control Scheme in Cloud-Based Services 被引量:3
11
作者 Kai Fan Qiong Tian +2 位作者 Junxiong Wang Hui Li Yintang Yang 《China Communications》 SCIE CSCD 2017年第1期61-71,共11页
With the rapid development of computer technology, cloud-based services have become a hot topic. They not only provide users with convenience, but also bring many security issues, such as data sharing and privacy issu... With the rapid development of computer technology, cloud-based services have become a hot topic. They not only provide users with convenience, but also bring many security issues, such as data sharing and privacy issue. In this paper, we present an access control system with privilege separation based on privacy protection(PS-ACS). In the PS-ACS scheme, we divide users into private domain(PRD) and public domain(PUD) logically. In PRD, to achieve read access permission and write access permission, we adopt the Key-Aggregate Encryption(KAE) and the Improved Attribute-based Signature(IABS) respectively. In PUD, we construct a new multi-authority ciphertext policy attribute-based encryption(CP-ABE) scheme with efficient decryption to avoid the issues of single point of failure and complicated key distribution, and design an efficient attribute revocation method for it. The analysis and simulation result show that our scheme is feasible and superior to protect users' privacy in cloud-based services. 展开更多
关键词 access control data sharing privacy protection cloud-based services
下载PDF
Notch signaling controls chondrocyte hypertrophy via indirect regulation of Sox9 被引量:9
12
作者 Anat Kohn Timothy P Rutkowski +4 位作者 Zhaoyang Liu Anthony J Mirando Michael J Zuscik Regis J O'Keefe Matthew J Hilton 《Bone Research》 SCIE CAS CSCD 2015年第3期140-151,共12页
RBPjk-dependent Notch signaling regulates both the onset of chondrocyte hypertrophy and the progression to terminal chondrocyte maturation during endochondral ossification. It has been suggested that Notch signaling c... RBPjk-dependent Notch signaling regulates both the onset of chondrocyte hypertrophy and the progression to terminal chondrocyte maturation during endochondral ossification. It has been suggested that Notch signaling can regulate Sox9 transcription, although how this occurs at the molecular level in chondrocytes and whether this transcriptional regulation mediates Notch control of chondrocyte hypertrophy and cartilage development is unknown or controversial. Here we have provided conclusive genetic evidence linking RBPjk-dependent Notch signaling to the regulation of Sox9 expression and chondrocyte hypertrophy by examining tissuespecific Rbpjk mutant(Prx1Cre;Rbpjkf/f), Rbpjk mutant/Sox9 haploinsufficient(Prx1Cre;Rbpjkf/f;Sox9f/1),and control embryos for alterations in SOX9 expression and chondrocyte hypertrophy during cartilage development. These studies demonstrate that Notch signaling regulates the onset of chondrocyte maturation in a SOX9-dependent manner, while Notch-mediated regulation of terminal chondrocyte maturation likely functions independently of SOX9. Furthermore, our in vitro molecular analyses of the Sox9 promoter and Notch-mediated regulation of Sox9 gene expression in chondrogenic cells identified the ability of Notch to induce Sox9 expression directly in the acute setting, but suppresses Sox9 transcription with prolonged Notch signaling that requires protein synthesis of secondary effectors. 展开更多
关键词 Figure Notch signaling controls chondrocyte hypertrophy via indirect regulation of Sox9 NICD SOX
下载PDF
Robust Non-fragile PID Controller Design for the Stroke Regulation of Metering Pumps 被引量:3
13
作者 余世明 吴江江 张端 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第1期83-88,共6页
This job focuses on the stroke regulation of a class of high-precision metering pumps.A parametertuning method of robust non-fragile PID(proportional-integral-derivative)controllers is proposed with the assumption t... This job focuses on the stroke regulation of a class of high-precision metering pumps.A parametertuning method of robust non-fragile PID(proportional-integral-derivative)controllers is proposed with the assumption that a PID controller has additive gain perturbations.An H-infinite robust PID controller can be obtained by solving a linear matrix inequality.This approach can guarantee that the closed-loop control systems is asymptotically stable and the H-infinite norm of the transfer function from the disturbance to the output of a controlled system is less than a given constant to attenuate disturbances.The simulation case shows that the control performance of the proposed strategy is significantly better than the traditional PID approach in the situation with perturbations of controller parameters. 展开更多
关键词 metering pump stroke regulation H-infinite robust control PID control NON-FRAGILE
下载PDF
High-Speed Trains Automatic Operation with Protection Constraints: A Resilient Nonlinear Gain-based Feedback Control Approach 被引量:2
14
作者 Shigen Gao Yuhan Hou +2 位作者 Hairong Dong Sebastian Stichel Bin Ning 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期992-999,共8页
This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of gua... This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of guaranteeing,under some proper non-restrictive initial conditions,the protection constraints control raised by the distance-to-go(moving authority)curve and automatic train protection in practice.A new hyperbolic tangent function-based model is presented to mimic the whole operation process of high-speed trains.The proposed feedback control methods are easily implementable and computationally inexpensive because the presence of only two feedback gains guarantee satisfactory tracking performance and closed-loop stability,no adaptations of unknown parameters,function approximation of unknown nonlinearities,and attenuation of external disturbances in the proposed control strategies.Finally,rigorous proofs and comparative simulation results are given to demonstrate the effectiveness of the proposed approaches. 展开更多
关键词 AUTOMATIC TRAIN operation high-speed TRAIN nonlinear GAIN feedback protection CONSTRAINT resilient control
下载PDF
Response of Osmotic Regulation Substance Content and Protective Enzyme Activities to Shading in Leaves of Different Rice Genotypes 被引量:2
15
作者 LIU Li WANG Li +4 位作者 DENG Fei HUANG Yun LIU Dai-yin REN Wan-jun YANG Wen-yu 《Rice science》 SCIE 2013年第4期276-283,共8页
Effects of shading at the flowering and grain filling stages on osmotic regulation substance content and protective enzyme activities in the leaves of different rice genotypes (e.g., Ilyou 498, Gangyou 188, Dexiang 4... Effects of shading at the flowering and grain filling stages on osmotic regulation substance content and protective enzyme activities in the leaves of different rice genotypes (e.g., Ilyou 498, Gangyou 188, Dexiang 4103, Gangyou 527 and Chuanxiang 9838) were investigated. The results showed that the malondialdehyde content of Gangyou 188 significantly increased under shading, whereas those of Ilyou 498, Dexiang 4103, Gangyou 527 and Chuanxiang 9838 showed no significant differences compared to the control. The soluble sugar content significantly decreased in Ilyou 498, Gangyou 188, Dexiang 4103 and Chuanxiang 9838, whereas it did not significantly increase in Gangyou 527 under the weak light conditions (shading). Moreover, the soluble protein content in the leaves of different genotypes tended to decrease under shading. Further, the protective enzyme activities in the leaves varied in different rice genotypes under the shading treatment. Based on the osmotic regulation substance content and the protective enzyme activities in the leaves of different rice genotypes, it was concluded that Gangyou 188 and Gangyou 527 had strong abilities to adapt to the low light conditions. In addition, the mechanism of damage to rice leaves in different genotypes under shading was discussed. 展开更多
关键词 malondialdehyde content osmotic regulation substance content protective enzyme rice genotype SHADING
下载PDF
Pressure Regulation for Earth Pressure Balance Control on Shield Tunneling Machine by Using Adaptive Robust Control 被引量:8
16
作者 XIE Haibo LIU Zhibin YANG Huayong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期598-606,共9页
Most current studies about shield tunneling machine focus on the construction safety and tunnel structure stability during the excavation. Behaviors of the machine itself are also studied, like some tracking control o... Most current studies about shield tunneling machine focus on the construction safety and tunnel structure stability during the excavation. Behaviors of the machine itself are also studied, like some tracking control of the machine. Yet, few works concern about the hydraulic components, especially the pressure and flow rate regulation components. This research focuses on pressure control strategies by using proportional pressure relief valve, which is widely applied on typical shield tunneling machines. Modeling of a commercial pressure relief valve is done. The modeling centers on the main valve, because the dynamic performance is determined by the main valve. To validate such modeling, a frequency-experiment result of the pressure relief valve, whose bandwidth is about 3 Hz, is presented as comparison. The modeling and the frequency experimental result show that it is reasonable to regard the pressure relief valve as a second-order system with two low corner frequencies. PID control, dead band compensation control and adaptive robust control(ARC) are proposed and simulation results are presented. For the ARC, implements by using first order approximation and second order approximation are presented. The simulation results show that the second order approximation implement with ARC can track 4 Hz sine signal very well, and the two ARC simulation errors are within 0.2 MPa. Finally, experiment results of dead band compensation control and adaptive robust control are given. The results show that dead band compensation had about 30° phase lag and about 20% off of the amplitude attenuation. ARC is tracking with little phase lag and almost no amplitude attenuation. In this research, ARC has been tested on a pressure relief valve. It is able to improve the valve's dynamic performances greatly, and it is capable of the pressure control of shield machine excavation. 展开更多
关键词 shield tunneling machine pressure regulation adaptive robust control
下载PDF
Adaptive Optimal Output Regulation of Interconnected Singularly Perturbed Systems With Application to Power Systems
17
作者 Jianguo Zhao Chunyu Yang +2 位作者 Weinan Gao Linna Zhou Xiaomin Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期595-607,共13页
This article studies the adaptive optimal output regulation problem for a class of interconnected singularly perturbed systems(SPSs) with unknown dynamics based on reinforcement learning(RL).Taking into account the sl... This article studies the adaptive optimal output regulation problem for a class of interconnected singularly perturbed systems(SPSs) with unknown dynamics based on reinforcement learning(RL).Taking into account the slow and fast characteristics among system states,the interconnected SPS is decomposed into the slow time-scale dynamics and the fast timescale dynamics through singular perturbation theory.For the fast time-scale dynamics with interconnections,we devise a decentralized optimal control strategy by selecting appropriate weight matrices in the cost function.For the slow time-scale dynamics with unknown system parameters,an off-policy RL algorithm with convergence guarantee is given to learn the optimal control strategy in terms of measurement data.By combining the slow and fast controllers,we establish the composite decentralized adaptive optimal output regulator,and rigorously analyze the stability and optimality of the closed-loop system.The proposed decomposition design not only bypasses the numerical stiffness but also alleviates the high-dimensionality.The efficacy of the proposed methodology is validated by a load-frequency control application of a two-area power system. 展开更多
关键词 Adaptive optimal control decentralized control output regulation reinforcement learning(RL) singularly perturbed systems(SPSs)
下载PDF
Architecture Design for Integrated Wide Area Protection and Control Systems 被引量:2
18
作者 Z. Q. Bo Q. P. Wang +3 位作者 Lin Wang Fengqun Zhou Shengming Ge B. M. Zhang 《Journal of Power and Energy Engineering》 2015年第4期412-416,共5页
This paper firstly reviews the recent development in power system protection and control, with special attention paid to the wide-area and integrated protection, in order to look into future development of integration... This paper firstly reviews the recent development in power system protection and control, with special attention paid to the wide-area and integrated protection, in order to look into future development of integration of protection and control for smart grids. This paper mainly reports on the development of integrated wide area protection and control for power systems. The concept of integrated wide area protection and control is introduced, in which a hierarchical protection and control system provides the protection and control of wide area or regional power substations/ plants and their associated power network. The system is mainly divided into three levels, the local, the substation/plant and the wide area/regional protection and control. The integrated functions at each level are described in details with an aim to develop an optimal coordination mechanism between the levels. One of the core elements in the system is the synchronised wide area communication network between the substations and the protection and control system, in which latest communication technology is employed. Another important player in the system is the wide area synchronized protection and control information platform, which not only enables the fusion three line of defence for power system protection and control, but also provides a perfect tool for the application of cloud computing to substations and power networks. 展开更多
关键词 INTEGRATED protection WIDE Area protection protection and control CLOUD COMPUTING
下载PDF
Event-triggered robust cooperative output regulation for a class of linear multi-agent systems with an unknown exosystem
19
作者 Yangyang Qian Lu Liu 《Journal of Automation and Intelligence》 2024年第2期119-127,共9页
This paper investigates the robust cooperative output regulation problem for a class of heterogeneousuncertain linear multi-agent systems with an unknown exosystem via event-triggered control (ETC). By utilizingthe in... This paper investigates the robust cooperative output regulation problem for a class of heterogeneousuncertain linear multi-agent systems with an unknown exosystem via event-triggered control (ETC). By utilizingthe internal model approach and the adaptive control technique, a distributed adaptive internal model isconstructed for each agent. Then, based on this internal model, a fully distributed ETC strategy composed ofa distributed event-triggered adaptive output feedback control law and a distributed dynamic event-triggeringmechanism is proposed, in which each agent updates its control input at its own triggering time instants. It isshown that under the proposed ETC strategy, the robust cooperative output regulation problem can be solvedwithout requiring either the global information associated with the communication topology or the bounds ofthe uncertain or unknown parameters in each agent and the exosystem. A numerical example is provided toillustrate the effectiveness of the proposed control strategy. 展开更多
关键词 Adaptive control Event-triggered control Internal model Multi-agent systems Output regulation
下载PDF
Flexural Property of String Beam of Pre-Stressed Glulam Based on Influence of Regulation and Control 被引量:2
20
作者 Nan Guo Wenbo Wang Hongliang Zuo 《Structural Durability & Health Monitoring》 EI 2019年第2期143-179,共37页
Applying pre-stress in glulam beam can reduce its deformation and make full use of the compressive strength of wood.However,when the glulam with low strength and the pre-stressed steel with high strength form combined... Applying pre-stress in glulam beam can reduce its deformation and make full use of the compressive strength of wood.However,when the glulam with low strength and the pre-stressed steel with high strength form combined members,materials of high strength can’t be fully utilized.Therefore,this study puts forward the idea of regulating and controlling string beam of pre-stressed glulam.By regulating and controlling the pre-stress,a part of the load borne by the wood is allocated to the pre-stressed tendon,which is equivalent to completing a redistribution of internal force,thus realizing the repeated utilization of the wood strength and the full utilization of the strength of the high-strength pre-stressed tendon.The bending experiments of 10 beams under 5 working conditions are carried out.The failure mode,bearing capacity and deformation of the beams are analyzed.The results show that 90%of beams are deformed under compression.The ultimate load of the regulated and controlled beam is obviously larger than that of the unregulated beam,and the ultimate load of the beam increases with the increase of the degree of regulation and control.Compared with that of the unregulated beams,the ultimate load of beams regulated by 7.5%-30%increases by 25.42%-65.08%,and the regulated and controlled effect is obvious.With the increase of the regulation and control amplitude of pre-stress,the stiffness of string beam of pre-stressed glulam increases.In addition,with the increase of the regulation and control amplitude,the compression height of the beam increases before the failure,and it reaches the state of full-section compression at the time of failure,giving full play to the compressive property of the glulam.At the end of the experiment,the constitutive relation which can reflect the anisotropy of the wood is established combined with the experimental data.The finite element analysis of the beam under 7 working conditions is carried out by using ABAQUS finite element program,and the influence of the regulation and control amplitude on the stress distribution and ultimate bearing capacity of the beam is discussed. 展开更多
关键词 STRING beam of GLULAM FLEXURAL PROPERTY experimental study PRE-STRESS regulation and control
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部