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
This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associat...This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associated fatty liver disease.We provide supplementary insights to their research,highlighting the broader systemic implications of GLP-1RAs,synthesizing the current understanding of their mechanisms and the trajectory of research in this field.GLP-1RAs are revolutionizing the treatment of type 2 diabetes mellitus and beyond.Beyond glycemic control,GLP-1RAs demonstrate cardiovascular and renal protective effects,offering potential in managing diabetic kidney disease alongside renin–angiotensin–aldosterone system inhibitors.Their role in bone metabolism hints at benefits for diabetic osteoporosis,while the neuroprotective properties of GLP-1RAs show promise in Alzheimer's disease treatment by modulating neuronal insulin signaling.Additionally,they improve hormonal and metabolic profiles in polycystic ovary syndrome.This editorial highlights the multifaceted mechanisms of GLP-1RAs,emphasizing the need for ongoing research to fully realize their therapeutic potential across a range of multisystemic diseases.展开更多
A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to...A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to poor performance.The method combines a fault-tolerant fault location method based on long-term and short-term memory networks to accurately locate the fault section.Then,an operation control method for relay protection based on adaptive weight and whale optimization algorithm(WOA)is used to construct an objective function considering the shortest relay protection action time and the smallest impulse current.The adaptive weight and WOA are employed to obtain the optimal strategy for relay protection operation control,reducing the action time and impulse current.Experimental results demonstrate the effectiveness of the proposed method in accurately locating faults and improving relay protection performance.The longest operation time is reduced by 4.7023 s,and the maximum impulse current is limited to 0.3 A,effectively controlling the impact of large impulse currents and enhancing control efficiency.展开更多
Supervisory control and data acquisition(SCADA)systems are computer systems that gather and analyze real-time data,distributed control systems are specially designed automated control system that consists of geographi...Supervisory control and data acquisition(SCADA)systems are computer systems that gather and analyze real-time data,distributed control systems are specially designed automated control system that consists of geographically distributed control elements,and other smaller control systems such as programmable logic controllers are industrial solid-state computers that monitor inputs and outputs and make logic-based decisions.In recent years,there has been a lot of focus on the security of industrial control systems.Due to the advancement in information technologies,the risk of cyberattacks on industrial control system has been drastically increased.Because they are so inextricably tied to human life,any damage to them might have devastating consequences.To provide an efficient solution to such problems,this paper proposes a new approach to intrusion detection.First,the important features in the dataset are determined by the difference between the distribution of unlabeled and positive data which is deployed for the learning process.Then,a prior estimation of the class is proposed based on a support vector machine.Simulation results show that the proposed approach has better anomaly detection performance than existing algorithms.展开更多
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
To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is ...To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability.展开更多
Generator control system decides whether the generator can work as usual or not, as well as its stability of performance. Both types of generators control system composed of the transistor and DSP are sensitive to out...Generator control system decides whether the generator can work as usual or not, as well as its stability of performance. Both types of generators control system composed of the transistor and DSP are sensitive to outward electromagnetic interference, directly related to the generator performance. In this text, we first analyze the electromagnetic interference threat generator control system of transistor type may face, then design a electromagnetic protection plan for the intake, the panel and the sense organ. This work is of great significance in improving its electromagnetic protection ability and stability of performance.展开更多
Supervisory control and protection system of the neutral beam injector (NBI) in the HL-2A tokamak is presented. The system is used for a safe coordination of all the main NBI subsystems. Because the system is based ...Supervisory control and protection system of the neutral beam injector (NBI) in the HL-2A tokamak is presented. The system is used for a safe coordination of all the main NBI subsystems. Because the system is based on computer networks with its transmission medium of optical fiber, its advantages in high operational stability, reliability, security and flexible functional expandability are clearly shown during the NBI commissioning and heating experiment in HL-2A.展开更多
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
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
Theoretical and practical issues concerning the multi-faceted task of mitigating the latero-torsional seismic response of a prototypal frame structure with asymmetric mass distribution are approached, Chevron braces w...Theoretical and practical issues concerning the multi-faceted task of mitigating the latero-torsional seismic response of a prototypal frame structure with asymmetric mass distribution are approached, Chevron braces with embedded magnetorheological dampers acting on the interstory drift are used to ensure additional energy dissipation. The semi-active control strategy employed to govern the modification of the damper characteristics via feedback is based on the selection of optimal forces according to a H2/LQG criterion, with respect to which the actual forces are regulated by a clipped-optimal logic. A dynamic observer is used to estimate the state through a non-collocated placement of the acceleration sensors. Several aspects to be addressed throughout the complex process including the design, modelization, and implementation phases of semi-active protection systems are discussed. Finally, experimental results obtained to mitigate the motion induced by ground excitation in a large-scale laboratory prototype, simulating the seismic response of a two-story building, are summarized.展开更多
This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Thr...This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Through the combination of three methods including literature review, visiting and investigational studies, and field surveys, the data of investigation, collection and collation were analyzed. According to data of surveys, collection and collation, problems related to the protection of wild Chinese herbal medicine resources faced by Longyuwan Scenic Spot within Funiu Mountain Nature Reserve were also analyzed and protection strategies and quality control of wild Chinese herbal medicine resources in this nature reserve were discussed. It was expected that the results would provide important scientific references for the sustainable development, protection and quality control of wild Chinese herbal medicine resources within nature reserves.展开更多
The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-bind...The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-binding site of the antibody prior to immo-bilization to -functionalized mixed self-assembled monolayer (SAM) of 12-mercaptododecanoic acid and 1-heptanethiol. More importantly, the number of immobilization bonds formed between each an-tigen-binding site protected antibody molecule and the solid surface was controlled by optimizing the mole fraction of the activated carboxyl group of the linker molecules in the mixed SAM. The amount of antibody used in this study was approximately equivalent to the amount for one monolayer surface coverage. The resulting activity of protected immo-bilized antibody was about 10 fold higher than that of random immobilized展开更多
Programmable Logic Controllers(PLC),core of industrial control systems,is widely used in industrial control systems.The security of PLC is the key to the security of industrial control systems.Nowadays,a large number ...Programmable Logic Controllers(PLC),core of industrial control systems,is widely used in industrial control systems.The security of PLC is the key to the security of industrial control systems.Nowadays,a large number of industrial control systems are connected to the Internet which exposes the PLC equipment to the Internet,and thus raising security concerns.First of all,we introduce the basic principle of PLC in this paper.Then we analyze the PLC code security,firmware security,network security,virus vulnerability and Modbus communication protocol by reviewing the previous related work.Finally,we make a summary of the current security protection methods.展开更多
The design idea of tracking-differentiator and the nonlinear PID controllerare introduced, the applicable algorithm and its real result for distributed aerodynamicsloading control system are discussed, and the constru...The design idea of tracking-differentiator and the nonlinear PID controllerare introduced, the applicable algorithm and its real result for distributed aerodynamicsloading control system are discussed, and the construction of the test & contro1 system arealso presented. The application shows that the nonlinear PID algorithm has the advan-tages of high reliability, short run time and strong stability.展开更多
Train control systems ensure the safety of railways. This paper begins with a summary of the typical train control systems in Japan and Europe. Based on this summary, the author then raises the following question rega...Train control systems ensure the safety of railways. This paper begins with a summary of the typical train control systems in Japan and Europe. Based on this summary, the author then raises the following question regarding current train control systems: What approach should be adopted in order to enhance the functionality, safety, and reliability of train control systems and assist in commercial operations on railways? Next, the author provides a desirable architecture that is likely to assist with the development of new train control systems based on current information and communication technologies. A new unified train control system (UTCS) is proposed that is effective in enhancing the robustness and com- petitiveness of a train control system. The ultimate architecture of the UTCS will be only composed of essential elements such as point machines and level crossing control devices in the field. Finally, a pro- cessing method of the UTCS is discussed.展开更多
It is widely acknowledged that masonry walls in RC (reinforced concrete) frame structures, although often omitted in the design process, contribute significantly on the seismic resistance of buildings. Their contrib...It is widely acknowledged that masonry walls in RC (reinforced concrete) frame structures, although often omitted in the design process, contribute significantly on the seismic resistance of buildings. Their contribution toward seismic response improvement is proportional to their participation level on buildings. The more abundant they are on buildings, their lateral strength contribution gets more significant, especially for "frame systems" of both RC and steel structures. This paper presents an "innovative" solution which aims to provide a seismic protection to masonry walls and to improve the seismic performance of the entire building structure. These goals are achieved through use of so called "IDRIZI" seismic devices. These "box-like" devices are placed at characteristic locations between the masonry infill walls and the structural frame system of the building. They act as special link elements between the top of wall panels and the bottom of beams and/or slabs. The assemblage of a wall panel, IDRIZI seismic devices and other boundary structural elements forms an integral structural system that is shortly called "IDRIZI" wall system. In addition, as part of this paper is shown selected experimental investigations, which demonstrate that under "optimal design" of buildings integrated with IDRIZI wall system, up to 80% of earthquake energy input in the structure can be dissipated by the friction mechanism of the IDRIZI devices. This feature provides remarkable improvements on the seismic performance of residential buildings or any other type of building where masonry walls are abundantly present.展开更多
In response to the frequent safety accidents of industrial robots, this paper designs and implements a safety detection system for robot control. It can perform real-time security detection of robot operations on indu...In response to the frequent safety accidents of industrial robots, this paper designs and implements a safety detection system for robot control. It can perform real-time security detection of robot operations on industrial production lines to improve the security and reliability of robot control systems. This paper designs and implements a robot control system based Snort-BASE for real-time online detection of DoS attacks. The system uses a six-degree-of-freedom robotic arm as an example, uses Snort to record the network communication data of the robot arm control system in real time, and filters the network traffic through self-defined rules, and then uses the BASE analysis platform to achieve security analysis of the network traffic. The solution verifies the effectiveness of online real-time detection of attacks and visualisation of attack records by designing simulated robotic arm and real robotic arm attack experiments respectively, thus achieving the security of network communication of the robot remote control system.展开更多
As capacity design philosophy suggests, the best way to achieve a safe seismic response of multistory buildings, under strong earthquakes, is to uniformly spread the inelastic deformation demands throughout the buildi...As capacity design philosophy suggests, the best way to achieve a safe seismic response of multistory buildings, under strong earthquakes, is to uniformly spread the inelastic deformation demands throughout the building structure. Unfortunately, this type of mechanism is difficult to be reached due to the abundant presence ofinfill wall panels on buildings, which under strong earthquakes show severe cracks and strength degradations, thus complicating the seismic response of buildings. In order to avoid these brittle mechanisms of failure, studies were made toward development of new seismic protection system which would completely protect the infill walls from any cracks and strength degradation manifestations and simultaneously improve the seismic response of the entire structure. Utilization of the "IDRIZI" seismic protection system, would greatly contribute to many important aspects, like the increase of structural seismic performance, drastic reduction of damages under strong earthquake events and avoiding any unpredictable local failure mechanisms on buildings.展开更多
基金the 2021 Key Project of Natural Science and Technology of Yangzhou Polytechnic Institute,Active Disturbance Rejection and Fault-Tolerant Control of Multi-Rotor Plant ProtectionUAV Based on QBall-X4(Grant Number 2021xjzk002).
文摘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.
基金Supported by National Natural Science Foundation of China,No.U23A20398 and No.82030007Sichuan Science and Technology Program,No.2022YFS0578.
文摘This editorial takes a deeper look at the insights provided by Soresi and Giannitrapani,which examined the therapeutic potential of glucagon-like peptide-1 receptor agonists(GLP-1RAs)for metabolic dysfunction-associated fatty liver disease.We provide supplementary insights to their research,highlighting the broader systemic implications of GLP-1RAs,synthesizing the current understanding of their mechanisms and the trajectory of research in this field.GLP-1RAs are revolutionizing the treatment of type 2 diabetes mellitus and beyond.Beyond glycemic control,GLP-1RAs demonstrate cardiovascular and renal protective effects,offering potential in managing diabetic kidney disease alongside renin–angiotensin–aldosterone system inhibitors.Their role in bone metabolism hints at benefits for diabetic osteoporosis,while the neuroprotective properties of GLP-1RAs show promise in Alzheimer's disease treatment by modulating neuronal insulin signaling.Additionally,they improve hormonal and metabolic profiles in polycystic ovary syndrome.This editorial highlights the multifaceted mechanisms of GLP-1RAs,emphasizing the need for ongoing research to fully realize their therapeutic potential across a range of multisystemic diseases.
文摘A novel operation control method for relay protection in flexible DC distribution networks with distributed power supply is proposed to address the issue of inaccurate fault location during relay protection,leading to poor performance.The method combines a fault-tolerant fault location method based on long-term and short-term memory networks to accurately locate the fault section.Then,an operation control method for relay protection based on adaptive weight and whale optimization algorithm(WOA)is used to construct an objective function considering the shortest relay protection action time and the smallest impulse current.The adaptive weight and WOA are employed to obtain the optimal strategy for relay protection operation control,reducing the action time and impulse current.Experimental results demonstrate the effectiveness of the proposed method in accurately locating faults and improving relay protection performance.The longest operation time is reduced by 4.7023 s,and the maximum impulse current is limited to 0.3 A,effectively controlling the impact of large impulse currents and enhancing control efficiency.
基金funded by the Research Deanship at the University of Ha’il-Saudi Arabia through Project Number RG-20146。
文摘Supervisory control and data acquisition(SCADA)systems are computer systems that gather and analyze real-time data,distributed control systems are specially designed automated control system that consists of geographically distributed control elements,and other smaller control systems such as programmable logic controllers are industrial solid-state computers that monitor inputs and outputs and make logic-based decisions.In recent years,there has been a lot of focus on the security of industrial control systems.Due to the advancement in information technologies,the risk of cyberattacks on industrial control system has been drastically increased.Because they are so inextricably tied to human life,any damage to them might have devastating consequences.To provide an efficient solution to such problems,this paper proposes a new approach to intrusion detection.First,the important features in the dataset are determined by the difference between the distribution of unlabeled and positive data which is deployed for the learning process.Then,a prior estimation of the class is proposed based on a support vector machine.Simulation results show that the proposed approach has better anomaly detection performance than existing algorithms.
文摘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.
文摘To fit in with the developing requirement of int and communication of protective relays, a protection egrated functions of protection measurement, control measurement and control system based on DeviceNet fieldbus is designed. The communication mechanism of DeviceNet is studied and data trigger modes, communication connection, message types and other key technologies are analyzed. The object modeling and device description of the device are realized too. Results of network test, dynamic simulation and test in the field indicate that this system can accomplish all the communication tasks in real time and can make precise response to every kind of faults of the motor, transformer, line and capacitor. Moreover, this system has higher measurement precision and better control capability.
文摘Generator control system decides whether the generator can work as usual or not, as well as its stability of performance. Both types of generators control system composed of the transistor and DSP are sensitive to outward electromagnetic interference, directly related to the generator performance. In this text, we first analyze the electromagnetic interference threat generator control system of transistor type may face, then design a electromagnetic protection plan for the intake, the panel and the sense organ. This work is of great significance in improving its electromagnetic protection ability and stability of performance.
文摘Supervisory control and protection system of the neutral beam injector (NBI) in the HL-2A tokamak is presented. The system is used for a safe coordination of all the main NBI subsystems. Because the system is based on computer networks with its transmission medium of optical fiber, its advantages in high operational stability, reliability, security and flexible functional expandability are clearly shown during the NBI commissioning and heating experiment in HL-2A.
基金financially supported by the National Natural Science Foundation of China(No.61303216,No.61272457,No.U1401251,and No.61373172)the National High Technology Research and Development Program of China(863 Program)(No.2012AA013102)National 111 Program of China B16037 and B08038
文摘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.
基金supported jointly by the National Natural Science Foundation of China(61703033,61790573)Beijing Natural Science Foundation(4192046)+1 种基金Fundamental Research Funds for Central Universities(2018JBZ002)State Key Laboratory of Rail Traffic Control and Safety(RCS2018ZT013),Beijing Jiaotong University
文摘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.
基金Project DPC-ReLUIS 2005-2008, RL n.7 "Technologies for the isolation and control of structures and infrastructures"
文摘Theoretical and practical issues concerning the multi-faceted task of mitigating the latero-torsional seismic response of a prototypal frame structure with asymmetric mass distribution are approached, Chevron braces with embedded magnetorheological dampers acting on the interstory drift are used to ensure additional energy dissipation. The semi-active control strategy employed to govern the modification of the damper characteristics via feedback is based on the selection of optimal forces according to a H2/LQG criterion, with respect to which the actual forces are regulated by a clipped-optimal logic. A dynamic observer is used to estimate the state through a non-collocated placement of the acceleration sensors. Several aspects to be addressed throughout the complex process including the design, modelization, and implementation phases of semi-active protection systems are discussed. Finally, experimental results obtained to mitigate the motion induced by ground excitation in a large-scale laboratory prototype, simulating the seismic response of a two-story building, are summarized.
基金Supported by Funding from the State Nationalities Affairs Commission(2015-GM-178)National Training Programs of Innovation and Entrepreneurship for Undergraduates(GCYS2016110001)
文摘This paper discussed how to protect and control the quality of wild Chinese herbal medicine resources in nature reserves by taking Longyuwan National Forest Park within Funiu Mountain Nature Reserve as an example. Through the combination of three methods including literature review, visiting and investigational studies, and field surveys, the data of investigation, collection and collation were analyzed. According to data of surveys, collection and collation, problems related to the protection of wild Chinese herbal medicine resources faced by Longyuwan Scenic Spot within Funiu Mountain Nature Reserve were also analyzed and protection strategies and quality control of wild Chinese herbal medicine resources in this nature reserve were discussed. It was expected that the results would provide important scientific references for the sustainable development, protection and quality control of wild Chinese herbal medicine resources within nature reserves.
文摘The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-binding site of the antibody prior to immo-bilization to -functionalized mixed self-assembled monolayer (SAM) of 12-mercaptododecanoic acid and 1-heptanethiol. More importantly, the number of immobilization bonds formed between each an-tigen-binding site protected antibody molecule and the solid surface was controlled by optimizing the mole fraction of the activated carboxyl group of the linker molecules in the mixed SAM. The amount of antibody used in this study was approximately equivalent to the amount for one monolayer surface coverage. The resulting activity of protected immo-bilized antibody was about 10 fold higher than that of random immobilized
基金This work is funded by the National Key Research and Development Plan(Grant No.2018YFB0803504)the National Natural Science Foundation of China(Nos.61702223,61702220,61871140,U1636215)the Opening Project of Shanghai Trusted Industrial Control Platform.
文摘Programmable Logic Controllers(PLC),core of industrial control systems,is widely used in industrial control systems.The security of PLC is the key to the security of industrial control systems.Nowadays,a large number of industrial control systems are connected to the Internet which exposes the PLC equipment to the Internet,and thus raising security concerns.First of all,we introduce the basic principle of PLC in this paper.Then we analyze the PLC code security,firmware security,network security,virus vulnerability and Modbus communication protocol by reviewing the previous related work.Finally,we make a summary of the current security protection methods.
文摘The design idea of tracking-differentiator and the nonlinear PID controllerare introduced, the applicable algorithm and its real result for distributed aerodynamicsloading control system are discussed, and the construction of the test & contro1 system arealso presented. The application shows that the nonlinear PID algorithm has the advan-tages of high reliability, short run time and strong stability.
文摘Train control systems ensure the safety of railways. This paper begins with a summary of the typical train control systems in Japan and Europe. Based on this summary, the author then raises the following question regarding current train control systems: What approach should be adopted in order to enhance the functionality, safety, and reliability of train control systems and assist in commercial operations on railways? Next, the author provides a desirable architecture that is likely to assist with the development of new train control systems based on current information and communication technologies. A new unified train control system (UTCS) is proposed that is effective in enhancing the robustness and com- petitiveness of a train control system. The ultimate architecture of the UTCS will be only composed of essential elements such as point machines and level crossing control devices in the field. Finally, a pro- cessing method of the UTCS is discussed.
文摘It is widely acknowledged that masonry walls in RC (reinforced concrete) frame structures, although often omitted in the design process, contribute significantly on the seismic resistance of buildings. Their contribution toward seismic response improvement is proportional to their participation level on buildings. The more abundant they are on buildings, their lateral strength contribution gets more significant, especially for "frame systems" of both RC and steel structures. This paper presents an "innovative" solution which aims to provide a seismic protection to masonry walls and to improve the seismic performance of the entire building structure. These goals are achieved through use of so called "IDRIZI" seismic devices. These "box-like" devices are placed at characteristic locations between the masonry infill walls and the structural frame system of the building. They act as special link elements between the top of wall panels and the bottom of beams and/or slabs. The assemblage of a wall panel, IDRIZI seismic devices and other boundary structural elements forms an integral structural system that is shortly called "IDRIZI" wall system. In addition, as part of this paper is shown selected experimental investigations, which demonstrate that under "optimal design" of buildings integrated with IDRIZI wall system, up to 80% of earthquake energy input in the structure can be dissipated by the friction mechanism of the IDRIZI devices. This feature provides remarkable improvements on the seismic performance of residential buildings or any other type of building where masonry walls are abundantly present.
文摘In response to the frequent safety accidents of industrial robots, this paper designs and implements a safety detection system for robot control. It can perform real-time security detection of robot operations on industrial production lines to improve the security and reliability of robot control systems. This paper designs and implements a robot control system based Snort-BASE for real-time online detection of DoS attacks. The system uses a six-degree-of-freedom robotic arm as an example, uses Snort to record the network communication data of the robot arm control system in real time, and filters the network traffic through self-defined rules, and then uses the BASE analysis platform to achieve security analysis of the network traffic. The solution verifies the effectiveness of online real-time detection of attacks and visualisation of attack records by designing simulated robotic arm and real robotic arm attack experiments respectively, thus achieving the security of network communication of the robot remote control system.
文摘As capacity design philosophy suggests, the best way to achieve a safe seismic response of multistory buildings, under strong earthquakes, is to uniformly spread the inelastic deformation demands throughout the building structure. Unfortunately, this type of mechanism is difficult to be reached due to the abundant presence ofinfill wall panels on buildings, which under strong earthquakes show severe cracks and strength degradations, thus complicating the seismic response of buildings. In order to avoid these brittle mechanisms of failure, studies were made toward development of new seismic protection system which would completely protect the infill walls from any cracks and strength degradation manifestations and simultaneously improve the seismic response of the entire structure. Utilization of the "IDRIZI" seismic protection system, would greatly contribute to many important aspects, like the increase of structural seismic performance, drastic reduction of damages under strong earthquake events and avoiding any unpredictable local failure mechanisms on buildings.