This paper establishes a new framework for modeling electrical cyber-physical systems(ECPSs),integrating both power grids and communication networks. To model the communication network associated with a power transmis...This paper establishes a new framework for modeling electrical cyber-physical systems(ECPSs),integrating both power grids and communication networks. To model the communication network associated with a power transmission grid, we use a mesh network that considers the features of power transmission grids such as high-voltage levels, long-transmission distances, and equal importance of each node. Moreover, bidirectional links including data uploading channels and command downloading channels are assumed to connect every node in the communication network and a corresponding physical node in the transmission grid. Based on this model,the fragility of an ECPS is analyzed under various cyber attacks including denial-of-service(Do S) attacks, replay attacks, and false data injection attacks. Control strategies such as load shedding and relay protection are also verified using this model against these attacks.展开更多
Cyber-physical electrical energy systems(CPEES)combine computation,communication and control technologies with physical power system,and realize the efficient fusion of power,information and control.This paper summari...Cyber-physical electrical energy systems(CPEES)combine computation,communication and control technologies with physical power system,and realize the efficient fusion of power,information and control.This paper summarizes and analyzes related critical scientific problems and technologies,which are needed to be addressed with the development of CPEES.Firstly,since the co-simulation is an effective method to investigate infrastructure interdependencies,the co-simulation platform establishment of CPEES and its evaluation is overviewed.Then,a critical problem of CPEES is the interaction between energy and information flow,especially the influence of failures happening in information communication technology(ICT)on power system.In order to figure it out,the interaction is analyzed and the current analysis methods are summarized.For the solution of power system control and protection in information network environment,this paper outlines different control principles and illustrates the concept of distributed coordination control.Moreover,mass data processing and cluster analysis,architecture of communication network,information transmission technology and security of CPEES are summarized and analyzed.By solving the above problems and technologies,the development of CPEES will be significantly promoted.展开更多
A three-dimensional elastic nonhydrostatic mesoscale(β-γ)model with nested-grid is presented.It uses a set of full equations in terrain-following coordinates as its basic dynamic frame,which is solved with a time-sp...A three-dimensional elastic nonhydrostatic mesoscale(β-γ)model with nested-grid is presented.It uses a set of full equations in terrain-following coordinates as its basic dynamic frame,which is solved with a time-splitting algorithm for acoustic and gravity waves.The model physical parameterization includes a K-theory subgrid eddy mixing for cloud and free atmosphere,a bulk planetary boundary layer parameterization,and three types of sofisticated cloud microphysics schemes with double-parameters for hail-bearing clouds,warm clouds and snowing clouds respectively. The model is designed to be used flexibly for simulations of a variety of meso-and small-scale atmospheric processes, and can be improved as a regional and local operational NWP system in future.展开更多
With the rapid development of deep submicron (DSM) VLSI circuit designs, many issues such as time closure and power consumption are making the physical designs more and more challenging. In this review paper we provid...With the rapid development of deep submicron (DSM) VLSI circuit designs, many issues such as time closure and power consumption are making the physical designs more and more challenging. In this review paper we provide readers with some recent progress of the VLSI physical designs. The recent developments of floorplanning and placement, interconnect effects, modeling and delay, buffer insertion and wire sizing, circuit order reduction, power grid analysis, parasitic extraction, and clock signal distribution are briefly reviewed.展开更多
基金Project supported by the National Basic Research Program(863)of China(No.2015AA05002)the National Natural Science Foundation of China(No.61471328)the Science and Technology Project of State Grid,China(No.XXB17201400056)
文摘This paper establishes a new framework for modeling electrical cyber-physical systems(ECPSs),integrating both power grids and communication networks. To model the communication network associated with a power transmission grid, we use a mesh network that considers the features of power transmission grids such as high-voltage levels, long-transmission distances, and equal importance of each node. Moreover, bidirectional links including data uploading channels and command downloading channels are assumed to connect every node in the communication network and a corresponding physical node in the transmission grid. Based on this model,the fragility of an ECPS is analyzed under various cyber attacks including denial-of-service(Do S) attacks, replay attacks, and false data injection attacks. Control strategies such as load shedding and relay protection are also verified using this model against these attacks.
基金supported by the national Natural Science Foundation of China(NSFC)under Grant 61233008 and 51377001by the International Science and Technology Cooperation Program of China under Grant 2015DFA70580by the State Grid Science and Technology Project of China under Grant 5216A213509X.
文摘Cyber-physical electrical energy systems(CPEES)combine computation,communication and control technologies with physical power system,and realize the efficient fusion of power,information and control.This paper summarizes and analyzes related critical scientific problems and technologies,which are needed to be addressed with the development of CPEES.Firstly,since the co-simulation is an effective method to investigate infrastructure interdependencies,the co-simulation platform establishment of CPEES and its evaluation is overviewed.Then,a critical problem of CPEES is the interaction between energy and information flow,especially the influence of failures happening in information communication technology(ICT)on power system.In order to figure it out,the interaction is analyzed and the current analysis methods are summarized.For the solution of power system control and protection in information network environment,this paper outlines different control principles and illustrates the concept of distributed coordination control.Moreover,mass data processing and cluster analysis,architecture of communication network,information transmission technology and security of CPEES are summarized and analyzed.By solving the above problems and technologies,the development of CPEES will be significantly promoted.
文摘A three-dimensional elastic nonhydrostatic mesoscale(β-γ)model with nested-grid is presented.It uses a set of full equations in terrain-following coordinates as its basic dynamic frame,which is solved with a time-splitting algorithm for acoustic and gravity waves.The model physical parameterization includes a K-theory subgrid eddy mixing for cloud and free atmosphere,a bulk planetary boundary layer parameterization,and three types of sofisticated cloud microphysics schemes with double-parameters for hail-bearing clouds,warm clouds and snowing clouds respectively. The model is designed to be used flexibly for simulations of a variety of meso-and small-scale atmospheric processes, and can be improved as a regional and local operational NWP system in future.
文摘With the rapid development of deep submicron (DSM) VLSI circuit designs, many issues such as time closure and power consumption are making the physical designs more and more challenging. In this review paper we provide readers with some recent progress of the VLSI physical designs. The recent developments of floorplanning and placement, interconnect effects, modeling and delay, buffer insertion and wire sizing, circuit order reduction, power grid analysis, parasitic extraction, and clock signal distribution are briefly reviewed.
