In order to continuously simulate multi-pass plate rolling process,a 3-D elastic hollow-roll model was proposed and an auto mesh-refining module with data passing was developed and integrated with FE software,Marc.The...In order to continuously simulate multi-pass plate rolling process,a 3-D elastic hollow-roll model was proposed and an auto mesh-refining module with data passing was developed and integrated with FE software,Marc.The hollow-roll model has equivalent stiffness of bending resistance and deformation to the real solid and much less meshes,so the computational time is greatly reduced.Based on these,the factors influencing plate profile,such as the roll-bending force,initial crown,thermal crown and heat transfer during rolling and inter-pass cooling can be taken into account in the simulation.The auto mesh-refining module with data passing can automatically refine and re-number elements and transfer the nodal and elemental results to the new meshes.Furthermore,the 3-D modeling routine is parametrically developed and can be run independently of Marc pre-processing program.A seven-pass industrial hot rolling process was continuously simulated to validate the accuracy of model.By comparison of the calculated results with the industrial measured data,the rolling force,temperature and plate profile are in good accordance with the measured ones.展开更多
Aimed at the lack of self-tuning PID parameters in conventional PID controllers, the structure and learning algorithm of an adaptive PID controller based on reinforcement learning were proposed. Actor-Critic learning ...Aimed at the lack of self-tuning PID parameters in conventional PID controllers, the structure and learning algorithm of an adaptive PID controller based on reinforcement learning were proposed. Actor-Critic learning was used to tune PID parameters in an adaptive way by taking advantage of the model-free and on-line learning properties of reinforcement learning effectively. In order to reduce the demand of storage space and to improve the learning efficiency, a single RBF neural network was used to approximate the policy function of Actor and the value function of Critic simultaneously. The inputs of RBF network are the system error, as well as the first and the second-order differences of error. The Actor can realize the mapping from the system state to PID parameters, while the Critic evaluates the outputs of the Actor and produces TD error. Based on TD error performance index and gradient descent method, the updating rules of RBF kernel function and network weights were given. Simulation results show that the proposed controller is efficient for complex nonlinear systems and it is perfectly adaptable and strongly robust, which is better than that of a conventional PID controller.展开更多
As system of a serial of technologies and engineering activities, remanufacturing aims at restoring and rebuilding waste machinery through advanced technologies and industrialized measures under the direction of the p...As system of a serial of technologies and engineering activities, remanufacturing aims at restoring and rebuilding waste machinery through advanced technologies and industrialized measures under the direction of the product total life cycle theory. With the development of surface engineering, nano-surface engineering has been one subject of intensive studies. In addition, nano-surface engineering has become an important means for property reforming and promoting of remanufacturing parts. Many low-dimension and nano-size or nano-structure functional coatings, which can improve materials properties evidently, are deposited by new methods. In this paper, some researches about the new achievement and remanufacturing application of the nano-stmctured coatings by different nano-surface engineering technologies in our laboratory were introduced. Especially, nano-structured DLC multilayer coatings by d.c. plasma CVD, nano-composed Al2O3/Ni, SiC/Ni and Diamond/Ni coatings by brush plating, and nano-composed Al2O3/TiO2 coating by plasma spraying were introduced in detail.展开更多
Research, performed by the authors proved that one of the most significant factors affecting the increase in flexibility and competitive ability of a firm is the conceptual, complex intra-plant standardization. The en...Research, performed by the authors proved that one of the most significant factors affecting the increase in flexibility and competitive ability of a firm is the conceptual, complex intra-plant standardization. The enterprise implementing the standardization is capable of flexible responding to customer's demands for the assortment, accelerates considerably research, and offers satisfactory delivery terms. That means the selection of types of the input factors and the method how to use them, the selection of working procedures and procedures of intermediary consumption, definition of the relations in the process of control, rational structure of the final products etc.. The permanent innovative atmosphere is presupposed.展开更多
This paper introduces a solution to the secure requirement for digital rights management (DRM) by the way of geospacial access control named geospacial access control (GeoAC) in geospacial field. The issues of aut...This paper introduces a solution to the secure requirement for digital rights management (DRM) by the way of geospacial access control named geospacial access control (GeoAC) in geospacial field. The issues of authorization for geospacial DRM are concentrated on. To geospacial DRM, one aspect is the declaration and enforcement of access rights, based on geographic aspects. To the approbation of digital geographic content, it is important to adopt online access to geodata through a special data infrastructure (SDI). This results in the interoperability requirements on three different levels: data model level, service level and access control level. The interaction between the data model and service level can be obtained by criterions of the open geospacial consortium (OGC), and the interaction of the access control level may be reached by declaring and enforcing access restrictions in GeoAC. Then an archetype enforcement based on GeoAC is elucidated. As one aspect of performing usage rights, the execution of access restrictions as an extension to a regular SDI is illuminated.展开更多
The speed and cost of A/D conversion are conflict to each other. As micro-controller speed is increasing and its internal function is improving, full utilization of its internal resource can dramatically increase A/D ...The speed and cost of A/D conversion are conflict to each other. As micro-controller speed is increasing and its internal function is improving, full utilization of its internal resource can dramatically increase A/D conversion speed and without compromising conversion quality. MSP430F11x1 series micro-controller is exploited to increase A/D conversion speed.展开更多
This paper presnts a team-oriented programming method specially designed for multiple mobile robots. The team, which is a typical constitution structure in multi-robot system, forms after the user selects suitable rob...This paper presnts a team-oriented programming method specially designed for multiple mobile robots. The team, which is a typical constitution structure in multi-robot system, forms after the user selects suitable robots, assigns their roles and sets related parameters. Team behavior module are introduced for the team-level behavior description and the temporal chain of these modules, realized by finite state automata, partitions the team tasks into discrete operating states and triggers. A graphical programming tool is designed for the team task description with visual diagrams. The real robots experiment of adaptive formation shows the system's usability and effectivity.展开更多
The economic crisis within the European Union also involves a crisis of democracy. On the one side the austerity-politics of the Troika limits the influence of democratic procedures. On the other side new forms of soc...The economic crisis within the European Union also involves a crisis of democracy. On the one side the austerity-politics of the Troika limits the influence of democratic procedures. On the other side new forms of social protests rise in which social actors struggle for an extension of the democratic public: the resistance against evictions the self-organization of medical care, the occupation of public places etc. realized new forms of social cooperation, discussion and decision-making processes. On this background a reference to John Deweys theory of the democratic public seems to be helpful to reconstruct and to orient these conflicts and the claims raised in them. According to Dewey the normative criteria which we use if we evaluate actions or common institutions are a part of the social process and insofar a process themselves. These criteria have to be reflected and reformulated in new situations in which new social problems and conflicts occur. The democratic public is in this conception the realm in which a common elucidation of problematic social consequences of the existing institutions takes place and in which proposals for the overcoming of these consequences are formulated. Therefore it reconstructs the central norms embedded within the social institutions, it shows how collective actions guided by these norms leads to problematic social consequences. This is then the background for a critical reflection on, and a reformulation of the guiding norms of these institutions. To realize such a form of collective self-determination the democratic public can not be reduced to a separate political sphere, rather it has to be extended to all forms of social cooperation especially the economy.展开更多
In this paper, the function characteristics of instruction are introduced, and the focus is on contact compare instruction and the characteristics of the transfer instructions. With the traffic lights control as an ex...In this paper, the function characteristics of instruction are introduced, and the focus is on contact compare instruction and the characteristics of the transfer instructions. With the traffic lights control as an example, this paper proposes the application of contact compare instruction and transfer instruction to program design method, making the program structure compact and statement concise. The control requirements are easily completed. Key words: Function Instruction; Programming; Traffic Lights; Contact Compare Instruction; Transfer展开更多
A different set of governing equations on the large deflection of plates are derived by the principle of virtual work(PVW), which also leads to a different set of boundary conditions. Boundary conditions play an impor...A different set of governing equations on the large deflection of plates are derived by the principle of virtual work(PVW), which also leads to a different set of boundary conditions. Boundary conditions play an important role in determining the computation accuracy of the large deflection of plates. Our boundary conditions are shown to be more appropriate by analyzing their difference with the previous ones. The accuracy of approximate analytical solutions is important to the bulge/blister tests and the application of various sensors with the plate structure. Different approximate analytical solutions are presented and their accuracies are evaluated by comparing them with the numerical results. The error sources are also analyzed. A new approximate analytical solution is proposed and shown to have a better approximation. The approximate analytical solution offers a much simpler and more direct framework to study the plate-membrane transition behavior of deflection as compared with the previous approaches of complex numerical integration.展开更多
基金Project(20050248007) supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘In order to continuously simulate multi-pass plate rolling process,a 3-D elastic hollow-roll model was proposed and an auto mesh-refining module with data passing was developed and integrated with FE software,Marc.The hollow-roll model has equivalent stiffness of bending resistance and deformation to the real solid and much less meshes,so the computational time is greatly reduced.Based on these,the factors influencing plate profile,such as the roll-bending force,initial crown,thermal crown and heat transfer during rolling and inter-pass cooling can be taken into account in the simulation.The auto mesh-refining module with data passing can automatically refine and re-number elements and transfer the nodal and elemental results to the new meshes.Furthermore,the 3-D modeling routine is parametrically developed and can be run independently of Marc pre-processing program.A seven-pass industrial hot rolling process was continuously simulated to validate the accuracy of model.By comparison of the calculated results with the industrial measured data,the rolling force,temperature and plate profile are in good accordance with the measured ones.
基金Projects 0601033B supported by the Science Foundation for Post-doctoral Scientists of Jiangsu Province, 0C4466 and 0C060093the Scientific and Technological Foundation for Youth of China University of Mining & Technology
文摘Aimed at the lack of self-tuning PID parameters in conventional PID controllers, the structure and learning algorithm of an adaptive PID controller based on reinforcement learning were proposed. Actor-Critic learning was used to tune PID parameters in an adaptive way by taking advantage of the model-free and on-line learning properties of reinforcement learning effectively. In order to reduce the demand of storage space and to improve the learning efficiency, a single RBF neural network was used to approximate the policy function of Actor and the value function of Critic simultaneously. The inputs of RBF network are the system error, as well as the first and the second-order differences of error. The Actor can realize the mapping from the system state to PID parameters, while the Critic evaluates the outputs of the Actor and produces TD error. Based on TD error performance index and gradient descent method, the updating rules of RBF kernel function and network weights were given. Simulation results show that the proposed controller is efficient for complex nonlinear systems and it is perfectly adaptable and strongly robust, which is better than that of a conventional PID controller.
基金National"973"Projects (G1999065009) andNational Natural Science Foundation of China (50075086)
文摘As system of a serial of technologies and engineering activities, remanufacturing aims at restoring and rebuilding waste machinery through advanced technologies and industrialized measures under the direction of the product total life cycle theory. With the development of surface engineering, nano-surface engineering has been one subject of intensive studies. In addition, nano-surface engineering has become an important means for property reforming and promoting of remanufacturing parts. Many low-dimension and nano-size or nano-structure functional coatings, which can improve materials properties evidently, are deposited by new methods. In this paper, some researches about the new achievement and remanufacturing application of the nano-stmctured coatings by different nano-surface engineering technologies in our laboratory were introduced. Especially, nano-structured DLC multilayer coatings by d.c. plasma CVD, nano-composed Al2O3/Ni, SiC/Ni and Diamond/Ni coatings by brush plating, and nano-composed Al2O3/TiO2 coating by plasma spraying were introduced in detail.
文摘Research, performed by the authors proved that one of the most significant factors affecting the increase in flexibility and competitive ability of a firm is the conceptual, complex intra-plant standardization. The enterprise implementing the standardization is capable of flexible responding to customer's demands for the assortment, accelerates considerably research, and offers satisfactory delivery terms. That means the selection of types of the input factors and the method how to use them, the selection of working procedures and procedures of intermediary consumption, definition of the relations in the process of control, rational structure of the final products etc.. The permanent innovative atmosphere is presupposed.
基金Funded by the Large-Scale Security SoC Project of Wuhan Science and Technology Bureau of China (No. 20061005119).
文摘This paper introduces a solution to the secure requirement for digital rights management (DRM) by the way of geospacial access control named geospacial access control (GeoAC) in geospacial field. The issues of authorization for geospacial DRM are concentrated on. To geospacial DRM, one aspect is the declaration and enforcement of access rights, based on geographic aspects. To the approbation of digital geographic content, it is important to adopt online access to geodata through a special data infrastructure (SDI). This results in the interoperability requirements on three different levels: data model level, service level and access control level. The interaction between the data model and service level can be obtained by criterions of the open geospacial consortium (OGC), and the interaction of the access control level may be reached by declaring and enforcing access restrictions in GeoAC. Then an archetype enforcement based on GeoAC is elucidated. As one aspect of performing usage rights, the execution of access restrictions as an extension to a regular SDI is illuminated.
文摘The speed and cost of A/D conversion are conflict to each other. As micro-controller speed is increasing and its internal function is improving, full utilization of its internal resource can dramatically increase A/D conversion speed and without compromising conversion quality. MSP430F11x1 series micro-controller is exploited to increase A/D conversion speed.
基金国家高技术研究发展计划(863计划),the National Natural Science Foundation of China
文摘This paper presnts a team-oriented programming method specially designed for multiple mobile robots. The team, which is a typical constitution structure in multi-robot system, forms after the user selects suitable robots, assigns their roles and sets related parameters. Team behavior module are introduced for the team-level behavior description and the temporal chain of these modules, realized by finite state automata, partitions the team tasks into discrete operating states and triggers. A graphical programming tool is designed for the team task description with visual diagrams. The real robots experiment of adaptive formation shows the system's usability and effectivity.
文摘The economic crisis within the European Union also involves a crisis of democracy. On the one side the austerity-politics of the Troika limits the influence of democratic procedures. On the other side new forms of social protests rise in which social actors struggle for an extension of the democratic public: the resistance against evictions the self-organization of medical care, the occupation of public places etc. realized new forms of social cooperation, discussion and decision-making processes. On this background a reference to John Deweys theory of the democratic public seems to be helpful to reconstruct and to orient these conflicts and the claims raised in them. According to Dewey the normative criteria which we use if we evaluate actions or common institutions are a part of the social process and insofar a process themselves. These criteria have to be reflected and reformulated in new situations in which new social problems and conflicts occur. The democratic public is in this conception the realm in which a common elucidation of problematic social consequences of the existing institutions takes place and in which proposals for the overcoming of these consequences are formulated. Therefore it reconstructs the central norms embedded within the social institutions, it shows how collective actions guided by these norms leads to problematic social consequences. This is then the background for a critical reflection on, and a reformulation of the guiding norms of these institutions. To realize such a form of collective self-determination the democratic public can not be reduced to a separate political sphere, rather it has to be extended to all forms of social cooperation especially the economy.
文摘In this paper, the function characteristics of instruction are introduced, and the focus is on contact compare instruction and the characteristics of the transfer instructions. With the traffic lights control as an example, this paper proposes the application of contact compare instruction and transfer instruction to program design method, making the program structure compact and statement concise. The control requirements are easily completed. Key words: Function Instruction; Programming; Traffic Lights; Contact Compare Instruction; Transfer
基金the National Natural Science Foundation of China(Grant No.11372321)
文摘A different set of governing equations on the large deflection of plates are derived by the principle of virtual work(PVW), which also leads to a different set of boundary conditions. Boundary conditions play an important role in determining the computation accuracy of the large deflection of plates. Our boundary conditions are shown to be more appropriate by analyzing their difference with the previous ones. The accuracy of approximate analytical solutions is important to the bulge/blister tests and the application of various sensors with the plate structure. Different approximate analytical solutions are presented and their accuracies are evaluated by comparing them with the numerical results. The error sources are also analyzed. A new approximate analytical solution is proposed and shown to have a better approximation. The approximate analytical solution offers a much simpler and more direct framework to study the plate-membrane transition behavior of deflection as compared with the previous approaches of complex numerical integration.