A new intelligent control method for welding positioner is proposed. Applying an improved fuzzy controller and a variable PID controller, a two-mode intelligent coordinating controller ( TMICC ) is designed on basis o...A new intelligent control method for welding positioner is proposed. Applying an improved fuzzy controller and a variable PID controller, a two-mode intelligent coordinating controller ( TMICC ) is designed on basis of fuzzy logic and rules. The simulation and experimental results show that this control system can obtain better dynamic and static characteristics.展开更多
In order to overcome the drawbacks of conventional artificial potential fields (APF) based methods for the motion planning problems of mobile robots in dynamic uncertain environments, an artificial coordinating fields...In order to overcome the drawbacks of conventional artificial potential fields (APF) based methods for the motion planning problems of mobile robots in dynamic uncertain environments, an artificial coordinating fields (ACF) based method has been proposed recently. This paper deals with the reachability problem of the ACF, that is, how to design and choose the parameters of the ACF and how the environment should be such that the robot can reach its goal without being trapped in local minima. Some sufficient conditions for these purposes are developed theoretically. Theoretical analyses show that, the ACF can effectively remove local minima in dynamic uncertain environments with V-shape or U-shape obstacles, and guide the mobile robot to reach its goal with some necessary environment constraints and based on the methods provided in this paper to properly choose the parameters of the ACF. Comparisons between the ACF and APF, and simulations are provided to illustrate the advantages of the ACF.展开更多
This paper studies the problem of coordinated motion generation for a group of rigid bodies. Two classes of coordinated motion primitives, relative equilibria and ma- neuvers, are given as building blocks for generati...This paper studies the problem of coordinated motion generation for a group of rigid bodies. Two classes of coordinated motion primitives, relative equilibria and ma- neuvers, are given as building blocks for generating coordi- nated motions. In a motion-primitive based planning frame- work, a control method is proposed for the robust execution of a coordinated motion plan in the presence of perturba- tions. The control method combines the relative equilibria stabilization with maneuver design, and results in a close- loop motion planning framework. The performance of the control method has been illustrated through a numerical sim- ulation.展开更多
The coordinating control system is popular used in power plant.This paper describes the advanced coordinating control by control methods and optimal operation,introduces their principals and features by using the exam...The coordinating control system is popular used in power plant.This paper describes the advanced coordinating control by control methods and optimal operation,introduces their principals and features by using the examples of power plant op- eration.It is wealthy for automation application in optimal power plant operation.展开更多
A sliding mode variable structure control (SMVSC) based on a coordinating optimization algorithm has been developed. Steady state error and control switching frequency are used to constitute the system performance i...A sliding mode variable structure control (SMVSC) based on a coordinating optimization algorithm has been developed. Steady state error and control switching frequency are used to constitute the system performance indexes in the coordinating optimization, while the tuning rate of boundary layer width (BLW) is employed as the optimization parameter. Based on the mathematical relationship between the BLW and steady-state error, an optimized BLW tuning rate is added to the nonlinear control term of SMVSC. Simulation experiment results applied to the positioning control of an electro-hydraulic servo system show the comprehensive superiority in dynamical and static state performance by using the proposed controller is better than that by using SMVSC without optimized BLW tuning rate. This succeeds in coordinately considering both chattering reduction and high-precision control realization in SMVSC.展开更多
In order to implement the spirit of the Sixteenth National People's Congress to accelerate development of rural education, deepen reform of rural education, guarantee a well-off society, and harmonize rural and urban...In order to implement the spirit of the Sixteenth National People's Congress to accelerate development of rural education, deepen reform of rural education, guarantee a well-off society, and harmonize rural and urban development, coordinating ruralurban education is the key to China's development. At present, the rural-urban coordinating education is influenced by many factors, including rural-urban income difference, rural-urban educational resources difference, rural-urban background difference, and rural- urban institutional difference. In order to realize the coordinating development of rural-urban education, we need innovation in "Hukou" institution, land institution, financial institution and rural education institution. Institution innovation would be the guarantee to the coordinating rural-urban education.展开更多
New thermotropic chloro-bridged dinuclear palladium coordinating imine side chain liquid crystalline polysiloxanes have been synthesized. Their mesomorphic properties have been investigated by DSC, X-ray diffraction a...New thermotropic chloro-bridged dinuclear palladium coordinating imine side chain liquid crystalline polysiloxanes have been synthesized. Their mesomorphic properties have been investigated by DSC, X-ray diffraction and polarizing microscopy. The polymeric complexes show nematicdiscotic (Nd) mesophase. It is found that the temperature range of liquid crystalline state of chloro- bridged polymeric complexes is much wider than that of acetato- bridged ones and imine side chain polysiloxane. This indicates that the disc-like chloro-bridged palladium complexing units play a role as mesogen in mesophase.展开更多
In May 2011, the Prison Management Bureau of Sichuan Province in Southwest China held a conference in its capital city Chengdu to discuss the management of severely sick prisoners. Coordinating Management on Major Dis...In May 2011, the Prison Management Bureau of Sichuan Province in Southwest China held a conference in its capital city Chengdu to discuss the management of severely sick prisoners. Coordinating Management on Major Diseases of Sick Prisoners in Sichuan (Trial) was issued then, marking the start of an overall deployment.展开更多
The thesis researches urban-rural coordination which is incorporated into the framework of "agriculture,rural areas and farmers",and it focuses on farmers' human resources development,agricultural indust...The thesis researches urban-rural coordination which is incorporated into the framework of "agriculture,rural areas and farmers",and it focuses on farmers' human resources development,agricultural industrial adjustment,rural regional coordinated development and so on.The main problems existing in the process of coordinating urban-rural development of Chongqing City are discussed under the foregoing framework.We find that input and flow direction of capital deviating from "agriculture,rural areas and farmers" is the direct cause of insufficient rural educational input,insufficient agricultural input,and irrational rural input,while the fundamental reason lies in the irrational financial policy.Based on this,the measures of innovating upon financial policy and financial system are put forward.展开更多
Faced with economic recession,firms struggle to find ways to stay competitive and maintain market share.Effective coordination of the supply chain can solve this problem,but this may fail if existing capital constrain...Faced with economic recession,firms struggle to find ways to stay competitive and maintain market share.Effective coordination of the supply chain can solve this problem,but this may fail if existing capital constraints and financial flows are ignored.This study addresses the challenge by exploiting coordination through joint decision-making on the physical and financial flows of a capital-constrained supply chain.We also consider the capital-constrained member’s financing limitations that lead to lost sales.Two scenarios based on non-coordinated and coordinated structures are modeled in the form of bi-objective optimization problems that simultaneously optimize system costs and service levels.The models are solved using the-constraint method.The results indicate that the non-coordinated model cannot satisfy more than about 50%of the demand due to capital shortage and financing limitations,while the coordinated model can satisfy all of the demand via internal financing.Furthermore,the proposed coordination scheme leads to cost reduction for the members and the total system.To motivate all members to accept the proposed coordination scheme,a cost-sharing mechanism is applied to the coordination procedure.Finally,a sensitivity analysis concerning financial parameters is provided for validating the coordination model.展开更多
It has been well identified that the extreme events significantly impact the system operation. In this work, a comprehensive operating strategy, which coordinates the preventive strategies and system restoration, was ...It has been well identified that the extreme events significantly impact the system operation. In this work, a comprehensive operating strategy, which coordinates the preventive strategies and system restoration, was proposed. A re-dispatch model that limits the potential loss under extreme events, as well as provides adequate resources for system restoration after the extreme events, was proposed. An optimal power flow based method was established to solve the proposed model. The availabilities of components and the remaining system due to the extreme events were restored by extending the EPRI’s System Restoration Navigator (SRN) with a little modification. Case studies demonstrate the proposed model and methods.展开更多
By setting the urban-rural public goods supply model,this paper evaluates the effects of coordinating supply public goods on resource allocation and welfare from efficiency and fairness,and examines the necessity and ...By setting the urban-rural public goods supply model,this paper evaluates the effects of coordinating supply public goods on resource allocation and welfare from efficiency and fairness,and examines the necessity and possibility of coordinating public goods supply in urban and rural areas. The model assumes that the population size of urban and rural areas is different,and the population can not flow freely between urban and rural areas; there are different degrees of spillover in the public goods supply. Model results show that coordinating public goods supply in urban and rural areas is the result of optimizing resource allocation efficiency,but the residents' individual utility level will not necessarily improve,so residents' willingness to support coordinated urban-rural supply is different,and public goods spillover and different tax systems are the factors that affect the residents' utility level. Finally,this paper uses the practice of coordinating urban and rural compulsory education in Chengdu City to confirm the above conclusions.展开更多
To establish the institutional mechanism for land conflict coordination in China, a case-based reasomng system is developed as an intelligent support and effective manner to resolve such issues. The establishment of t...To establish the institutional mechanism for land conflict coordination in China, a case-based reasomng system is developed as an intelligent support and effective manner to resolve such issues. The establishment of the case library is discussed, previous land conflict cases are archived in a structural representation format for retrieval, and the similarity algorithm is adopted to compare the case features. Group tests show a good classification performance, which reveals that the system is feasible.展开更多
State-society boundary organizations face the challenge to maintain autonomy as well as flexibilities to respond to various goals and needs of state and non-state actors.Chinese state used to exert much control over i...State-society boundary organizations face the challenge to maintain autonomy as well as flexibilities to respond to various goals and needs of state and non-state actors.Chinese state used to exert much control over intermediary NGOs(boundary organizations)and some have become bureaucratized.Recent reforms have sought to transform them to be more autonomous from the government and more responsive to NGOs.This paper investigates the managerial autonomy and coordinating mechanisms of 29 intermediary NGOs in Shanghai,Beijing and Guangdong.Regardless whether they are initiated by the state or non-state actors,as boundary organizations,they can effectively play a bridging role when they simultaneously deploy multiple mechanisms to sustain autonomy and at the same time integrate differences of interests between state and non-state actors.展开更多
Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a ...Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robots dynamic constraints. The direction of the coordinating force can be determined on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.展开更多
Vehicles operating in space need to withstand extreme thermal and electromagnetic environments in light of the burgeoning of space science and technology.It is imperatively desired to high insulation materials with li...Vehicles operating in space need to withstand extreme thermal and electromagnetic environments in light of the burgeoning of space science and technology.It is imperatively desired to high insulation materials with lightweight and extensive mechanical properties.Herein,a boron-silica-tantalum ternary hybrid phenolic aerogel(BSiTa-PA)with exceptional thermal stability,extensive mechanical strength,low thermal conductivity(49.6 mW m^(-1)K^(-1)),and heightened ablative resistance is prepared by an expeditious method.After extremely thermal erosion,the obtained carbon aerogel demonstrates noteworthy electromagnetic interference(EMI)shielding performance with an efficiency of 31.6 dB,accompanied by notable loading property with specific modulus of 272.8 kN·m kg^(-1).This novel design concept has laid the foundation for the development of insulation materials in more complex extreme environments.展开更多
文摘A new intelligent control method for welding positioner is proposed. Applying an improved fuzzy controller and a variable PID controller, a two-mode intelligent coordinating controller ( TMICC ) is designed on basis of fuzzy logic and rules. The simulation and experimental results show that this control system can obtain better dynamic and static characteristics.
基金This paper was partly supported by the National Natural Science Foundation (No.60131160741,60334010) of China.
文摘In order to overcome the drawbacks of conventional artificial potential fields (APF) based methods for the motion planning problems of mobile robots in dynamic uncertain environments, an artificial coordinating fields (ACF) based method has been proposed recently. This paper deals with the reachability problem of the ACF, that is, how to design and choose the parameters of the ACF and how the environment should be such that the robot can reach its goal without being trapped in local minima. Some sufficient conditions for these purposes are developed theoretically. Theoretical analyses show that, the ACF can effectively remove local minima in dynamic uncertain environments with V-shape or U-shape obstacles, and guide the mobile robot to reach its goal with some necessary environment constraints and based on the methods provided in this paper to properly choose the parameters of the ACF. Comparisons between the ACF and APF, and simulations are provided to illustrate the advantages of the ACF.
基金supported by the National Natural Science Foundation of China (11072002,10832006)
文摘This paper studies the problem of coordinated motion generation for a group of rigid bodies. Two classes of coordinated motion primitives, relative equilibria and ma- neuvers, are given as building blocks for generating coordi- nated motions. In a motion-primitive based planning frame- work, a control method is proposed for the robust execution of a coordinated motion plan in the presence of perturba- tions. The control method combines the relative equilibria stabilization with maneuver design, and results in a close- loop motion planning framework. The performance of the control method has been illustrated through a numerical sim- ulation.
文摘The coordinating control system is popular used in power plant.This paper describes the advanced coordinating control by control methods and optimal operation,introduces their principals and features by using the examples of power plant op- eration.It is wealthy for automation application in optimal power plant operation.
基金This work was supported by the Provincial Natural Science Foundation of Hunan(No.04JJ6033) the Research Foundation of Hunan Education Bureau (No.03C066).
文摘A sliding mode variable structure control (SMVSC) based on a coordinating optimization algorithm has been developed. Steady state error and control switching frequency are used to constitute the system performance indexes in the coordinating optimization, while the tuning rate of boundary layer width (BLW) is employed as the optimization parameter. Based on the mathematical relationship between the BLW and steady-state error, an optimized BLW tuning rate is added to the nonlinear control term of SMVSC. Simulation experiment results applied to the positioning control of an electro-hydraulic servo system show the comprehensive superiority in dynamical and static state performance by using the proposed controller is better than that by using SMVSC without optimized BLW tuning rate. This succeeds in coordinately considering both chattering reduction and high-precision control realization in SMVSC.
文摘In order to implement the spirit of the Sixteenth National People's Congress to accelerate development of rural education, deepen reform of rural education, guarantee a well-off society, and harmonize rural and urban development, coordinating ruralurban education is the key to China's development. At present, the rural-urban coordinating education is influenced by many factors, including rural-urban income difference, rural-urban educational resources difference, rural-urban background difference, and rural- urban institutional difference. In order to realize the coordinating development of rural-urban education, we need innovation in "Hukou" institution, land institution, financial institution and rural education institution. Institution innovation would be the guarantee to the coordinating rural-urban education.
文摘New thermotropic chloro-bridged dinuclear palladium coordinating imine side chain liquid crystalline polysiloxanes have been synthesized. Their mesomorphic properties have been investigated by DSC, X-ray diffraction and polarizing microscopy. The polymeric complexes show nematicdiscotic (Nd) mesophase. It is found that the temperature range of liquid crystalline state of chloro- bridged polymeric complexes is much wider than that of acetato- bridged ones and imine side chain polysiloxane. This indicates that the disc-like chloro-bridged palladium complexing units play a role as mesogen in mesophase.
文摘In May 2011, the Prison Management Bureau of Sichuan Province in Southwest China held a conference in its capital city Chengdu to discuss the management of severely sick prisoners. Coordinating Management on Major Diseases of Sick Prisoners in Sichuan (Trial) was issued then, marking the start of an overall deployment.
文摘The thesis researches urban-rural coordination which is incorporated into the framework of "agriculture,rural areas and farmers",and it focuses on farmers' human resources development,agricultural industrial adjustment,rural regional coordinated development and so on.The main problems existing in the process of coordinating urban-rural development of Chongqing City are discussed under the foregoing framework.We find that input and flow direction of capital deviating from "agriculture,rural areas and farmers" is the direct cause of insufficient rural educational input,insufficient agricultural input,and irrational rural input,while the fundamental reason lies in the irrational financial policy.Based on this,the measures of innovating upon financial policy and financial system are put forward.
文摘Faced with economic recession,firms struggle to find ways to stay competitive and maintain market share.Effective coordination of the supply chain can solve this problem,but this may fail if existing capital constraints and financial flows are ignored.This study addresses the challenge by exploiting coordination through joint decision-making on the physical and financial flows of a capital-constrained supply chain.We also consider the capital-constrained member’s financing limitations that lead to lost sales.Two scenarios based on non-coordinated and coordinated structures are modeled in the form of bi-objective optimization problems that simultaneously optimize system costs and service levels.The models are solved using the-constraint method.The results indicate that the non-coordinated model cannot satisfy more than about 50%of the demand due to capital shortage and financing limitations,while the coordinated model can satisfy all of the demand via internal financing.Furthermore,the proposed coordination scheme leads to cost reduction for the members and the total system.To motivate all members to accept the proposed coordination scheme,a cost-sharing mechanism is applied to the coordination procedure.Finally,a sensitivity analysis concerning financial parameters is provided for validating the coordination model.
文摘It has been well identified that the extreme events significantly impact the system operation. In this work, a comprehensive operating strategy, which coordinates the preventive strategies and system restoration, was proposed. A re-dispatch model that limits the potential loss under extreme events, as well as provides adequate resources for system restoration after the extreme events, was proposed. An optimal power flow based method was established to solve the proposed model. The availabilities of components and the remaining system due to the extreme events were restored by extending the EPRI’s System Restoration Navigator (SRN) with a little modification. Case studies demonstrate the proposed model and methods.
基金Supported by Fundamental Research Funds for Central Universities,Southwest University(SWU1109028)Southwest University Youth Foundation(SWU07104)Key Humanities and Social Sciences Research Project in Chongqing City(13SKB022)
文摘By setting the urban-rural public goods supply model,this paper evaluates the effects of coordinating supply public goods on resource allocation and welfare from efficiency and fairness,and examines the necessity and possibility of coordinating public goods supply in urban and rural areas. The model assumes that the population size of urban and rural areas is different,and the population can not flow freely between urban and rural areas; there are different degrees of spillover in the public goods supply. Model results show that coordinating public goods supply in urban and rural areas is the result of optimizing resource allocation efficiency,but the residents' individual utility level will not necessarily improve,so residents' willingness to support coordinated urban-rural supply is different,and public goods spillover and different tax systems are the factors that affect the residents' utility level. Finally,this paper uses the practice of coordinating urban and rural compulsory education in Chengdu City to confirm the above conclusions.
基金The National Natural Science Foundationof China (No70573036)
文摘To establish the institutional mechanism for land conflict coordination in China, a case-based reasomng system is developed as an intelligent support and effective manner to resolve such issues. The establishment of the case library is discussed, previous land conflict cases are archived in a structural representation format for retrieval, and the similarity algorithm is adopted to compare the case features. Group tests show a good classification performance, which reveals that the system is feasible.
文摘State-society boundary organizations face the challenge to maintain autonomy as well as flexibilities to respond to various goals and needs of state and non-state actors.Chinese state used to exert much control over intermediary NGOs(boundary organizations)and some have become bureaucratized.Recent reforms have sought to transform them to be more autonomous from the government and more responsive to NGOs.This paper investigates the managerial autonomy and coordinating mechanisms of 29 intermediary NGOs in Shanghai,Beijing and Guangdong.Regardless whether they are initiated by the state or non-state actors,as boundary organizations,they can effectively play a bridging role when they simultaneously deploy multiple mechanisms to sustain autonomy and at the same time integrate differences of interests between state and non-state actors.
基金the National Natural Science Foundation of China (Grant Nos. 60131160741 , 60334010).
文摘Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robots dynamic constraints. The direction of the coordinating force can be determined on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.
基金the support from the Joint Fund of Advanced Aerospace Manufacturing Technology Research of National Natural Science Foundation of China(U1837601)National Natural Science Foundation of China(52273255)+3 种基金NASF Joint Fund of National Natural Science Foundation of China and China Academy of Engineering Physics(U2130118)China Postdoctoral Science Foundation(2023M732029)Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(CX2023092)Undergraduate Innovation&Business Program in Northwestern Polytechnical University(XN2022226)。
文摘Vehicles operating in space need to withstand extreme thermal and electromagnetic environments in light of the burgeoning of space science and technology.It is imperatively desired to high insulation materials with lightweight and extensive mechanical properties.Herein,a boron-silica-tantalum ternary hybrid phenolic aerogel(BSiTa-PA)with exceptional thermal stability,extensive mechanical strength,low thermal conductivity(49.6 mW m^(-1)K^(-1)),and heightened ablative resistance is prepared by an expeditious method.After extremely thermal erosion,the obtained carbon aerogel demonstrates noteworthy electromagnetic interference(EMI)shielding performance with an efficiency of 31.6 dB,accompanied by notable loading property with specific modulus of 272.8 kN·m kg^(-1).This novel design concept has laid the foundation for the development of insulation materials in more complex extreme environments.