The identification of variations in the dynamic behavior of structures is an important subject in structural integrity assessment.Improvement and servicing of offshore platforms in the marine environment with constant...The identification of variations in the dynamic behavior of structures is an important subject in structural integrity assessment.Improvement and servicing of offshore platforms in the marine environment with constant changing,requires understanding the real behavior of these structures to prevent possible failure.In this work,empirical and numerical models of jacket structure are investigated.A test on experimental modal analysis is accomplished to acquire the response of structure and a mathematical model of the jacket structure is also performed.Then,based on the control theory using developed reduction system,the matrices of the platform model is calibrated and updated.The current methodology can be applied to prepare the finite element model to be more adaptable to the empirical model.Calibrated results with the proposed approach in this paper are very close to those of the actual model and also this technique leads to a reduction in the amount of calculations and expenses.The research clearly confirms that the dynamic behavior of fixed marine structures should be designed and assessed considering the calibrated analytical models for the safety of these structures.展开更多
In the construction of a soft rock tunnel,it is critical to accurately estimate the pre-stressed anchor support parameters for surrounding rock reinforcement;otherwise,engineering disasters may occur.This paper presen...In the construction of a soft rock tunnel,it is critical to accurately estimate the pre-stressed anchor support parameters for surrounding rock reinforcement;otherwise,engineering disasters may occur.This paper presents a support parameter selection method that aims to allow deformation as a control objective,which was applied to the tunnel located in Muzailing Highway,Min County,Dingxi City,Gansu Province,China.Through theoretical analysis,we have identified five factors that influence pre-stressing anchorages.The selection of mechanical parameters for the rock mass was carried out using an inverse analysis method.Compared with the measured data,the maximum displacement error of the numerical simulation results was only 0.07 m.The length of anchor cable,circumferential spacing of anchor cable,longitudinal spacing,and pre-stress index are adopted as the input parameters for the support vector machine neural network model based on particle swarm optimization(PSO-LSSVM).Besides,the vault subsidence and the maximum deformation of surrounding rock are considered as output values(performance indices).The goodness of fit between the predicted values and the simulated values exceeds 0.9.Finally,all support parameters within the acceptable deformation range are calculated.The optimal support variables are derived by considering the construction cost and duration.The field application results show that it is feasible to construct the sample database utilizing the numerical simulation approach by taking the displacement as the control target and using the neural network to specify the appropriate support parameters.展开更多
Considering the instability of data transferred existing in high speed network, a new method is proposed for improving the stability using control theory. Under this method, the mathematical model of such a network is...Considering the instability of data transferred existing in high speed network, a new method is proposed for improving the stability using control theory. Under this method, the mathematical model of such a network is established. Stability condition is derived from the mathematical model. Several simulation experiments are performed. The results show that the method can increase the stability of data transferred in terms of the congestion window, queue size, and sending rate of the source.展开更多
The paper addresses the problem of reconciling the modern control paradigm developed by R. Kalman in the sixties of the past century, and the centenary error-based design of the proportional, integrative and derivati...The paper addresses the problem of reconciling the modern control paradigm developed by R. Kalman in the sixties of the past century, and the centenary error-based design of the proportional, integrative and derivative （PID） controllers. This is done with the help of the error loop whose stability is proved to be necessary and sufficient for the close-loop plant stability. The error loop is built by cascading the uncertain plant-to-model discrepancies （causal, parametric, initial state, neglected dynamics）, which are driven by the design model output and by arbitrary bounded signals, with the control unit transfer functions. The embedded model control takes advantage of the error loop and its equations to design appropriate algorithms of the modern control theory （state predictor, control law, reference generator）, which guarantee the error loop stability and performance. A simulated multivariate case study shows modeling and control design steps and the coherence of the predicted and simulated performance.展开更多
Based on perceptual control theory,a task analysis approach is proposed to describe more accurately user tasks in dynamic environments,which is of more powerful and flexible descriptive ability. Theoretically,a task m...Based on perceptual control theory,a task analysis approach is proposed to describe more accurately user tasks in dynamic environments,which is of more powerful and flexible descriptive ability. Theoretically,a task meta model is established to describe the interactive process in an individual,dynamic,and flexible way.Methodologically,an implementation framework is illustrated to map the user-oriented description into implementation-oriented models,which will be as a technical tool to transform from a task model to a user interface prototype.展开更多
Recently, switched control systems have been attracting much attention m the control community because the problems are not only academically challenging for the inherent complexity, but also of practical importance d...Recently, switched control systems have been attracting much attention m the control community because the problems are not only academically challenging for the inherent complexity, but also of practical importance due to its wide ranges of applications in nature, engineering, and social sciences.展开更多
Wireless Sensor Network （WSN） is characterized by the dense deployment of sensor nodes that continuously observe physical phenomenon. The main advantages of WSN include its low cost, rapid deployment, self-organizat...Wireless Sensor Network （WSN） is characterized by the dense deployment of sensor nodes that continuously observe physical phenomenon. The main advantages of WSN include its low cost, rapid deployment, self-organization, and fault tolerance. WSN has received tremendous interests of various research communities,展开更多
Respiratory variables, including tidal volume and respiratory rate, display significant variability. The probability density function (PDF) of respiratory variables has been shown to contain clinical information and c...Respiratory variables, including tidal volume and respiratory rate, display significant variability. The probability density function (PDF) of respiratory variables has been shown to contain clinical information and can predict the risk for exacerbation in asthma. However, it is uncertain why this PDF plays a major role in predicting the dynamic conditions of the respiratory system. This paper introduces a stochastic optimal control model for noisy spontaneous breathing, and obtains a Shrödinger’s wave equation as the motion equation that can produce a PDF as a solution. Based on the lobules-bronchial tree model of the lung system, the tidal volume variable was expressed by a polar coordinate, by use of which the Shrödinger’s wave equation of inter-breath intervals (IBIs) was obtained. Through the wave equation of IBIs, the respiratory rhythm generator was characterized by the potential function including the PDF and the parameter concerning the topographical distribution of regional pulmonary ventilations. The stochastic model in this study was assumed to have a common variance parameter in the state variables, which would originate from the variability in metabolic energy at the cell level. As a conclusion, the PDF of IBIs would become a marker of neuroplasticity in the respiratory rhythm generator through Shr?dinger’s wave equation for IBIs.展开更多
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
It is our great pleasure to put up this special issue in Journal of Control Theory and Applications in honor of the 60th birthday of Professor Frank Lewis, who has made many significant contributions to the field of c...It is our great pleasure to put up this special issue in Journal of Control Theory and Applications in honor of the 60th birthday of Professor Frank Lewis, who has made many significant contributions to the field of control engineering through the years, and who is regarded as a pioneer in many areas in control and automation, which includes applied optimal control and geometric systems theory in his earlier research period, and his recent focus on intelligent nonlinear control,展开更多
Locus of control theory,which was developed by Rotter,suggests that there are two main types of peoples’behaviors when attributing their failure or success of their life events:external locus of control and internal....Locus of control theory,which was developed by Rotter,suggests that there are two main types of peoples’behaviors when attributing their failure or success of their life events:external locus of control and internal.The way that individuals act is determined by their expectations of their specific behaviors and the value that they add to these expectations.For instance,people who fit in the internal category are more likely to attribute their life events to their own behaviors,skills,and attitudes,while people who fit in the external category,tend to attribute their acts to fate,chance,and other exterior factors that are out of their control.The aim of this systematic literature review was to define the fundamental concept of LOC theory,to investigate major findings of the theory in accordance with LOC and procrastination,job satisfaction,and performance and lastly,to discuss the practical use of the theory in the organizational context.展开更多
The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising...The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising with increasing frequency in widely different areas, which cannot be addressed using conventional control techniques. The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where presence of large uncertainties as well as nonlinearities plays a major role. For instance, the design of unmanned aircraft, unmanned underwater vehicles, and automatic driving systems for automobiles are all typical examples of such difficult control problems. The large uncertainties concerning the plant may arise due to large external disturbances, large parameter variations because of faults in the system, or failure of some of the subsystems. In such cases, the controller has to determine the specific situation that exists at any instant, and take the appropriate control action. Accomplishing this rapidly, accurately, and in a stable fashion is the objective of control design.展开更多
文摘The identification of variations in the dynamic behavior of structures is an important subject in structural integrity assessment.Improvement and servicing of offshore platforms in the marine environment with constant changing,requires understanding the real behavior of these structures to prevent possible failure.In this work,empirical and numerical models of jacket structure are investigated.A test on experimental modal analysis is accomplished to acquire the response of structure and a mathematical model of the jacket structure is also performed.Then,based on the control theory using developed reduction system,the matrices of the platform model is calibrated and updated.The current methodology can be applied to prepare the finite element model to be more adaptable to the empirical model.Calibrated results with the proposed approach in this paper are very close to those of the actual model and also this technique leads to a reduction in the amount of calculations and expenses.The research clearly confirms that the dynamic behavior of fixed marine structures should be designed and assessed considering the calibrated analytical models for the safety of these structures.
基金supported by the Open Fund of State Key Laboratory of High speed Railway Track Technology(2022YJ127-1)National Natural Science Foundation of China(52104125,41941018)+1 种基金the Natural Science Basic Research Plan in Shaanxi Province of China(2022JQ-304)the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)。
文摘In the construction of a soft rock tunnel,it is critical to accurately estimate the pre-stressed anchor support parameters for surrounding rock reinforcement;otherwise,engineering disasters may occur.This paper presents a support parameter selection method that aims to allow deformation as a control objective,which was applied to the tunnel located in Muzailing Highway,Min County,Dingxi City,Gansu Province,China.Through theoretical analysis,we have identified five factors that influence pre-stressing anchorages.The selection of mechanical parameters for the rock mass was carried out using an inverse analysis method.Compared with the measured data,the maximum displacement error of the numerical simulation results was only 0.07 m.The length of anchor cable,circumferential spacing of anchor cable,longitudinal spacing,and pre-stress index are adopted as the input parameters for the support vector machine neural network model based on particle swarm optimization(PSO-LSSVM).Besides,the vault subsidence and the maximum deformation of surrounding rock are considered as output values(performance indices).The goodness of fit between the predicted values and the simulated values exceeds 0.9.Finally,all support parameters within the acceptable deformation range are calculated.The optimal support variables are derived by considering the construction cost and duration.The field application results show that it is feasible to construct the sample database utilizing the numerical simulation approach by taking the displacement as the control target and using the neural network to specify the appropriate support parameters.
基金the National Natural Science Foundation of China (50579022 50539140).
文摘Considering the instability of data transferred existing in high speed network, a new method is proposed for improving the stability using control theory. Under this method, the mathematical model of such a network is established. Stability condition is derived from the mathematical model. Several simulation experiments are performed. The results show that the method can increase the stability of data transferred in terms of the congestion window, queue size, and sending rate of the source.
文摘The paper addresses the problem of reconciling the modern control paradigm developed by R. Kalman in the sixties of the past century, and the centenary error-based design of the proportional, integrative and derivative （PID） controllers. This is done with the help of the error loop whose stability is proved to be necessary and sufficient for the close-loop plant stability. The error loop is built by cascading the uncertain plant-to-model discrepancies （causal, parametric, initial state, neglected dynamics）, which are driven by the design model output and by arbitrary bounded signals, with the control unit transfer functions. The embedded model control takes advantage of the error loop and its equations to design appropriate algorithms of the modern control theory （state predictor, control law, reference generator）, which guarantee the error loop stability and performance. A simulated multivariate case study shows modeling and control design steps and the coherence of the predicted and simulated performance.
基金Supported by the National Natural Science Foundation of China(61272286)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20126101110006)
文摘Based on perceptual control theory,a task analysis approach is proposed to describe more accurately user tasks in dynamic environments,which is of more powerful and flexible descriptive ability. Theoretically,a task meta model is established to describe the interactive process in an individual,dynamic,and flexible way.Methodologically,an implementation framework is illustrated to map the user-oriented description into implementation-oriented models,which will be as a technical tool to transform from a task model to a user interface prototype.
文摘Recently, switched control systems have been attracting much attention m the control community because the problems are not only academically challenging for the inherent complexity, but also of practical importance due to its wide ranges of applications in nature, engineering, and social sciences.
文摘Wireless Sensor Network （WSN） is characterized by the dense deployment of sensor nodes that continuously observe physical phenomenon. The main advantages of WSN include its low cost, rapid deployment, self-organization, and fault tolerance. WSN has received tremendous interests of various research communities,
文摘Respiratory variables, including tidal volume and respiratory rate, display significant variability. The probability density function (PDF) of respiratory variables has been shown to contain clinical information and can predict the risk for exacerbation in asthma. However, it is uncertain why this PDF plays a major role in predicting the dynamic conditions of the respiratory system. This paper introduces a stochastic optimal control model for noisy spontaneous breathing, and obtains a Shrödinger’s wave equation as the motion equation that can produce a PDF as a solution. Based on the lobules-bronchial tree model of the lung system, the tidal volume variable was expressed by a polar coordinate, by use of which the Shrödinger’s wave equation of inter-breath intervals (IBIs) was obtained. Through the wave equation of IBIs, the respiratory rhythm generator was characterized by the potential function including the PDF and the parameter concerning the topographical distribution of regional pulmonary ventilations. The stochastic model in this study was assumed to have a common variance parameter in the state variables, which would originate from the variability in metabolic energy at the cell level. As a conclusion, the PDF of IBIs would become a marker of neuroplasticity in the respiratory rhythm generator through Shr?dinger’s wave equation for IBIs.
文摘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.
文摘It is our great pleasure to put up this special issue in Journal of Control Theory and Applications in honor of the 60th birthday of Professor Frank Lewis, who has made many significant contributions to the field of control engineering through the years, and who is regarded as a pioneer in many areas in control and automation, which includes applied optimal control and geometric systems theory in his earlier research period, and his recent focus on intelligent nonlinear control,
文摘Locus of control theory,which was developed by Rotter,suggests that there are two main types of peoples’behaviors when attributing their failure or success of their life events:external locus of control and internal.The way that individuals act is determined by their expectations of their specific behaviors and the value that they add to these expectations.For instance,people who fit in the internal category are more likely to attribute their life events to their own behaviors,skills,and attitudes,while people who fit in the external category,tend to attribute their acts to fate,chance,and other exterior factors that are out of their control.The aim of this systematic literature review was to define the fundamental concept of LOC theory,to investigate major findings of the theory in accordance with LOC and procrastination,job satisfaction,and performance and lastly,to discuss the practical use of the theory in the organizational context.
文摘The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory. In recent years control problems have been arising with increasing frequency in widely different areas, which cannot be addressed using conventional control techniques. The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where presence of large uncertainties as well as nonlinearities plays a major role. For instance, the design of unmanned aircraft, unmanned underwater vehicles, and automatic driving systems for automobiles are all typical examples of such difficult control problems. The large uncertainties concerning the plant may arise due to large external disturbances, large parameter variations because of faults in the system, or failure of some of the subsystems. In such cases, the controller has to determine the specific situation that exists at any instant, and take the appropriate control action. Accomplishing this rapidly, accurately, and in a stable fashion is the objective of control design.
