The original Olami-Feder-Christensen （OFC） model, which displays a robust power-law behavior, is a quasistatic two-dimensional version of the Burridge-Knopoff spring-block model of earthquakes. In this paper, we int...The original Olami-Feder-Christensen （OFC） model, which displays a robust power-law behavior, is a quasistatic two-dimensional version of the Burridge-Knopoff spring-block model of earthquakes. In this paper, we introduce a modified OFC model based on heterogeneous network, improving the redistribution rule of the original model. It can be seen as a generalization of the originM OFC model We numerically investigate the influence of the parameters θandβ, which respectively control the intensity of the evolutive mechanism of the topological growth and the inner selection dynamics in our networks, and find that there are two distinct phases in the parameter space （θ,β）. Meanwhile, we study the influence of the control parameter a either. Increasing a, the earthquake behavior of the model transfers from local to global.展开更多
Transformers utilizing HTS （high temperature superconductors） are considered as a timely invention. The number of power transformers age more than 30 years old and nearing retirement is increasing. If this window of...Transformers utilizing HTS （high temperature superconductors） are considered as a timely invention. The number of power transformers age more than 30 years old and nearing retirement is increasing. If this window of opportunity is not grabbed, there would be great reluctance to replace recently installed highly priced capital asset. Major projects of developing HTS transformers are well making progress in the United States, Europe, Japan, Korea and China which indicate the interest. The efforts must have been appropriately verified through the economic interest of the discounted losses. Consequently, it is very important to develop an understanding of the fundamental HTS transformer design issues that can provide guidance for developing practical devices of interest to the electric utility industry. The parameters of HTS transformer need to be validated before any effort is to carry out to model the behaviour of a distribution network under a range of conditions. The predicted performance and reliability of HTS transformers can then be verified through the network modelling and analysis calculation. The ultimate purpose is to furnish electric utilities precise information as to which HTS transformers work under various applications with greater technical efficiency and proven reliability.展开更多
The structural evolution of dislocation network is closely related to y' rafting and tensile properties. In this work, the effects of strain rate and temperature on the structural evolution of interface dislocatio...The structural evolution of dislocation network is closely related to y' rafting and tensile properties. In this work, the effects of strain rate and temperature on the structural evolution of interface dislocation network in Ni-based superalloys are studied by molecular dynamics simulations. The correlation between the evolution of dislocation network and tensile properties is also explored. The results indicate that the dislocation network shows different degrees of deformation and damage at various strain rates and temperatures. The ),' rafting depends on the damage structure of dislocation network at various strain rates and tem- peratures. Moreover, the tensile properties of interface in Ni-based superalloys are closely related to the evolution of disloca- tion network and dislocation motion mechanisms.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No.10675060
文摘The original Olami-Feder-Christensen （OFC） model, which displays a robust power-law behavior, is a quasistatic two-dimensional version of the Burridge-Knopoff spring-block model of earthquakes. In this paper, we introduce a modified OFC model based on heterogeneous network, improving the redistribution rule of the original model. It can be seen as a generalization of the originM OFC model We numerically investigate the influence of the parameters θandβ, which respectively control the intensity of the evolutive mechanism of the topological growth and the inner selection dynamics in our networks, and find that there are two distinct phases in the parameter space （θ,β）. Meanwhile, we study the influence of the control parameter a either. Increasing a, the earthquake behavior of the model transfers from local to global.
文摘Transformers utilizing HTS （high temperature superconductors） are considered as a timely invention. The number of power transformers age more than 30 years old and nearing retirement is increasing. If this window of opportunity is not grabbed, there would be great reluctance to replace recently installed highly priced capital asset. Major projects of developing HTS transformers are well making progress in the United States, Europe, Japan, Korea and China which indicate the interest. The efforts must have been appropriately verified through the economic interest of the discounted losses. Consequently, it is very important to develop an understanding of the fundamental HTS transformer design issues that can provide guidance for developing practical devices of interest to the electric utility industry. The parameters of HTS transformer need to be validated before any effort is to carry out to model the behaviour of a distribution network under a range of conditions. The predicted performance and reliability of HTS transformers can then be verified through the network modelling and analysis calculation. The ultimate purpose is to furnish electric utilities precise information as to which HTS transformers work under various applications with greater technical efficiency and proven reliability.
基金supported by the National Natural Science Foundation of China (Grant Nos. 11072026 and 11102139)the Fundamental Research Funds for the Central Universities (Grant No. 2009JBZ015)China Postdoctoral Science Foundation (Grant No. 20110491205)
文摘The structural evolution of dislocation network is closely related to y' rafting and tensile properties. In this work, the effects of strain rate and temperature on the structural evolution of interface dislocation network in Ni-based superalloys are studied by molecular dynamics simulations. The correlation between the evolution of dislocation network and tensile properties is also explored. The results indicate that the dislocation network shows different degrees of deformation and damage at various strain rates and temperatures. The ),' rafting depends on the damage structure of dislocation network at various strain rates and tem- peratures. Moreover, the tensile properties of interface in Ni-based superalloys are closely related to the evolution of disloca- tion network and dislocation motion mechanisms.
