以糯扎渡—鹤山±800 kV特高压直流输电系统为研究对象,利用电力系统计算机辅助设计和电磁暂态模拟程序软件(power system computer aided design and electric magnetic transient in DC system,PSCAD/EMTDC),建立交流系统、换流...以糯扎渡—鹤山±800 kV特高压直流输电系统为研究对象,利用电力系统计算机辅助设计和电磁暂态模拟程序软件(power system computer aided design and electric magnetic transient in DC system,PSCAD/EMTDC),建立交流系统、换流器、换流变压器、交直流滤波器、直流平波电抗器、直流输电线路的仿真模型,并在这个仿真平台上进行单极、双极全压仿真模拟分析,仿真结果表明所建模型较准确地模拟糯扎渡—鹤山特高压直流输电系统,可以作为研究特高压直流输电系统的有效工具。展开更多
Subjected to various stochastic factors, surface mining engineering reliability is difficult to solve by using general reliability mathematical method.The concept of reliability measurement is introduced; And the auth...Subjected to various stochastic factors, surface mining engineering reliability is difficult to solve by using general reliability mathematical method.The concept of reliability measurement is introduced; And the authors have combined system simulation method with CAD technique and developed an interactive color character graphic design system for evaluating and solving the mining engineering reliability in surface mines under the given constraints.展开更多
Simulation and optimization are the key points of virtual product development (VPD). Traditional engineering simulation software and optimization methods are inadequate to analyze the optimization problems because of ...Simulation and optimization are the key points of virtual product development (VPD). Traditional engineering simulation software and optimization methods are inadequate to analyze the optimization problems because of its computational inefficiency. A systematic design optimization strategy by using statistical methods and mathematical optimization technologies is proposed. This method extends the design of experiments (DOE) and the simulation metamodel technologies. Metamodels are built to in place of detailed simulation codes based on effectively DOE, and then be linked to optimization routines for fast analysis, or serve as a bridge for integrating simulation software across different domains. A design optimization of composite material structure is used to demonstrate the newly introduced methodology.展开更多
An extended π calculus was introduced to deal with secure movement and intercommunication between agents. The system extends Nomadic-π with objective migration primitive and confined region which serves as annotatio...An extended π calculus was introduced to deal with secure movement and intercommunication between agents. The system extends Nomadic-π with objective migration primitive and confined region which serves as annotation labels of agents and channels. The confined region labels were used to uniquely identify the constraints on the migration and communication of agents, with the labels, the agents could be confined in a secure subsystem and the inter-agent communication could be confined between agents located on trusted sites during computation. The operational semantics for the calculus was given out, and a type system which enforces security properties called confined migration and confined communication was developed.展开更多
Due to the widespread computer technology, it is difficult to imagine a research or a control of any physical object without using a powerful hardware and software applications. To use digital technologies we need to ...Due to the widespread computer technology, it is difficult to imagine a research or a control of any physical object without using a powerful hardware and software applications. To use digital technologies we need to collect data of a real world in digital system by the analog-to-digital converters. Taking into account the relative high computational capabilities of modern microcontrollers the article proposes a multirate processing system. The paper presents practical design aspects of the analog and digital anti-aliasing filter fbr the measurement path. having regarded the real possibilities and limitations of today＇s filters and analog-to-digital embedded converters.展开更多
This paper used the virtual reality modeling language （VRML） to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual reali...This paper used the virtual reality modeling language （VRML） to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual realization experiment platform, the interface has friendly interface, stable operation, strong practicability like with the Windows style, is a kind of reform for the traditional physics experiment teaching mode. The system has practical use value, also has reference value for the reform and modernization of other experimental courses.展开更多
This paper presents the design method of hybrid drive system for the minibus with some limited conditions. The approach of design hybrid drive system is based on the dynamic modeling and simulation of the hybrid minib...This paper presents the design method of hybrid drive system for the minibus with some limited conditions. The approach of design hybrid drive system is based on the dynamic modeling and simulation of the hybrid minibus with planetary gear system. The main target of the design is to obtain the optimal design with the proper hybrid drive configuration and control for a given set of design constraints. In oder to meet the design target, it＇s necessary to adjust some parameters such as mechanical ratios and parameters of battery pack as well as control by simulation. During simulation the transient operating process can be studied in details with the dynamic model in Matlab/Simulink. The control strategy can be optimized by running the simulation and monitoring the operation of each components： the operating area of internal combustion engine （ICE）, fuel consumption （energy consumption）, the power distribution, the torque and rotary speed of ICE and motor, the operating efficiency of motor, the aheration of battery state of charge （SOC）, current and voltage.展开更多
This paper presents the development of a new technique to monitor the operating conditions of a grounding device of high voltage apparatus and systems without any diggings and forced outages. The model is based on the...This paper presents the development of a new technique to monitor the operating conditions of a grounding device of high voltage apparatus and systems without any diggings and forced outages. The model is based on the evaluation of the magnetic field distribution along the current-carrying horizontal element when it has been deteriorated or broken. A mathematical model which can be used to analyze and evaluate the integrity of the grounding device has been developed. Computer simulation studies were conducted to validate the effectiveness of the proposed model.展开更多
文摘以糯扎渡—鹤山±800 kV特高压直流输电系统为研究对象,利用电力系统计算机辅助设计和电磁暂态模拟程序软件(power system computer aided design and electric magnetic transient in DC system,PSCAD/EMTDC),建立交流系统、换流器、换流变压器、交直流滤波器、直流平波电抗器、直流输电线路的仿真模型,并在这个仿真平台上进行单极、双极全压仿真模拟分析,仿真结果表明所建模型较准确地模拟糯扎渡—鹤山特高压直流输电系统,可以作为研究特高压直流输电系统的有效工具。
文摘Subjected to various stochastic factors, surface mining engineering reliability is difficult to solve by using general reliability mathematical method.The concept of reliability measurement is introduced; And the authors have combined system simulation method with CAD technique and developed an interactive color character graphic design system for evaluating and solving the mining engineering reliability in surface mines under the given constraints.
文摘Simulation and optimization are the key points of virtual product development (VPD). Traditional engineering simulation software and optimization methods are inadequate to analyze the optimization problems because of its computational inefficiency. A systematic design optimization strategy by using statistical methods and mathematical optimization technologies is proposed. This method extends the design of experiments (DOE) and the simulation metamodel technologies. Metamodels are built to in place of detailed simulation codes based on effectively DOE, and then be linked to optimization routines for fast analysis, or serve as a bridge for integrating simulation software across different domains. A design optimization of composite material structure is used to demonstrate the newly introduced methodology.
基金The National Defense Project of China(No417010602)
文摘An extended π calculus was introduced to deal with secure movement and intercommunication between agents. The system extends Nomadic-π with objective migration primitive and confined region which serves as annotation labels of agents and channels. The confined region labels were used to uniquely identify the constraints on the migration and communication of agents, with the labels, the agents could be confined in a secure subsystem and the inter-agent communication could be confined between agents located on trusted sites during computation. The operational semantics for the calculus was given out, and a type system which enforces security properties called confined migration and confined communication was developed.
文摘Due to the widespread computer technology, it is difficult to imagine a research or a control of any physical object without using a powerful hardware and software applications. To use digital technologies we need to collect data of a real world in digital system by the analog-to-digital converters. Taking into account the relative high computational capabilities of modern microcontrollers the article proposes a multirate processing system. The paper presents practical design aspects of the analog and digital anti-aliasing filter fbr the measurement path. having regarded the real possibilities and limitations of today＇s filters and analog-to-digital embedded converters.
文摘This paper used the virtual reality modeling language （VRML） to establish the 3D virtual experiment instrument model, and by using the visual programming language VB to design and develop a interactive virtual realization experiment platform, the interface has friendly interface, stable operation, strong practicability like with the Windows style, is a kind of reform for the traditional physics experiment teaching mode. The system has practical use value, also has reference value for the reform and modernization of other experimental courses.
文摘This paper presents the design method of hybrid drive system for the minibus with some limited conditions. The approach of design hybrid drive system is based on the dynamic modeling and simulation of the hybrid minibus with planetary gear system. The main target of the design is to obtain the optimal design with the proper hybrid drive configuration and control for a given set of design constraints. In oder to meet the design target, it＇s necessary to adjust some parameters such as mechanical ratios and parameters of battery pack as well as control by simulation. During simulation the transient operating process can be studied in details with the dynamic model in Matlab/Simulink. The control strategy can be optimized by running the simulation and monitoring the operation of each components： the operating area of internal combustion engine （ICE）, fuel consumption （energy consumption）, the power distribution, the torque and rotary speed of ICE and motor, the operating efficiency of motor, the aheration of battery state of charge （SOC）, current and voltage.
文摘This paper presents the development of a new technique to monitor the operating conditions of a grounding device of high voltage apparatus and systems without any diggings and forced outages. The model is based on the evaluation of the magnetic field distribution along the current-carrying horizontal element when it has been deteriorated or broken. A mathematical model which can be used to analyze and evaluate the integrity of the grounding device has been developed. Computer simulation studies were conducted to validate the effectiveness of the proposed model.
