Hydraulic fracturing （HF） technique has been extensively used for the exploitation of unconventional oiland gas reservoirs. HF enhances the connectivity of less permeable oil and gas-bearing rock formationsby fluid ...Hydraulic fracturing （HF） technique has been extensively used for the exploitation of unconventional oiland gas reservoirs. HF enhances the connectivity of less permeable oil and gas-bearing rock formationsby fluid injection, which creates an interconnected fracture network and increases the hydrocarbonproduction. Meanwhile, microseismic （MS） monitoring is one of the most effective approaches to evaluatesuch stimulation process. In this paper, the combined finite-discrete element method （FDEM） isadopted to numerically simulate HF and associated MS. Several post-processing tools, includingfrequency-magnitude distribution （b-value）, fractal dimension （D-value）, and seismic events clustering,are utilized to interpret numerical results. A non-parametric clustering algorithm designed specificallyfor FDEM is used to reduce the mesh dependency and extract more realistic seismic information.Simulation results indicated that at the local scale, the HF process tends to propagate following the rockmass discontinuities; while at the reservoir scale, it tends to develop in the direction parallel to themaximum in-situ stress. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.展开更多
Nowadays,mobile operators in China mainland are facing fierce competition from one to another,and their focus of customer competition has,in general,shifted from public to corporate customers.One big challenge in corp...Nowadays,mobile operators in China mainland are facing fierce competition from one to another,and their focus of customer competition has,in general,shifted from public to corporate customers.One big challenge in corporate customer management is how to identify fake corporate members and potential corporate members from corporate customers.In this study,we have proposed an identification method that combines the rule-based and probabilistic methods.Through this method,fake corporate members can be eliminated and external potential members can be mined.The experimental results based on the data obtained from a local mobile operator revealed that the proposed method can effectively and efficiently identify fake and potential corporate members.The proposed method can be used to improve the management of corporate customers.展开更多
The Beijing-Tianjin-Hebei region,Yangtze River Delta,and Guangdong-Hong Kong-Macao Greater Bay Area and other urban agglomerations are emerging as important drivers of high-quality economic development.This paper esta...The Beijing-Tianjin-Hebei region,Yangtze River Delta,and Guangdong-Hong Kong-Macao Greater Bay Area and other urban agglomerations are emerging as important drivers of high-quality economic development.This paper establishes an evaluation indicator system to assess the levels of high-quality economic development in these urban agglomerations based on the new development philosophy.Utilizing the CRITIC-Entropy weight method and kernel density estimation method,this paper measures and compares the levels of high-quality economic development in the three urban agglomerations from 2011 to 2020 and analyzes the factors influencing their high-quality development.The findings indicate that all three urban agglomerations exhibit a stable upward trend in high-quality development,with diminishing relative differences among them.From a dimensional perspective,each agglomeration has unique strengths and weaknesses in terms of highquality economic development.The innovation and entrepreneurship level,urbanization,advanced industrial structure,environmental regulation,marketization,and transportation infrastructure play significant roles in fostering high-quality economic development.展开更多
基金supported by the Natural Sciences and Engineering Research Council of Canada through Discovery Grant 341275 (G. Grasselli) and Engage EGP 461019-13
文摘Hydraulic fracturing （HF） technique has been extensively used for the exploitation of unconventional oiland gas reservoirs. HF enhances the connectivity of less permeable oil and gas-bearing rock formationsby fluid injection, which creates an interconnected fracture network and increases the hydrocarbonproduction. Meanwhile, microseismic （MS） monitoring is one of the most effective approaches to evaluatesuch stimulation process. In this paper, the combined finite-discrete element method （FDEM） isadopted to numerically simulate HF and associated MS. Several post-processing tools, includingfrequency-magnitude distribution （b-value）, fractal dimension （D-value）, and seismic events clustering,are utilized to interpret numerical results. A non-parametric clustering algorithm designed specificallyfor FDEM is used to reduce the mesh dependency and extract more realistic seismic information.Simulation results indicated that at the local scale, the HF process tends to propagate following the rockmass discontinuities; while at the reservoir scale, it tends to develop in the direction parallel to themaximum in-situ stress. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.
基金supported by the Youth Research and Innovation Program in Beijing University of Posts and Telecommunications under Grants No. 2012RC1006,No. 2012RC1008the National Key Basic Research Program of China (973 Program) under Grant No.2012CB315805and the National Natural Science Foundation of China under Grant No.71172135
文摘Nowadays,mobile operators in China mainland are facing fierce competition from one to another,and their focus of customer competition has,in general,shifted from public to corporate customers.One big challenge in corporate customer management is how to identify fake corporate members and potential corporate members from corporate customers.In this study,we have proposed an identification method that combines the rule-based and probabilistic methods.Through this method,fake corporate members can be eliminated and external potential members can be mined.The experimental results based on the data obtained from a local mobile operator revealed that the proposed method can effectively and efficiently identify fake and potential corporate members.The proposed method can be used to improve the management of corporate customers.
基金supported by the key project“Comparison and Policy Research on Highquality Economic Development Path between Beijing-Tianjin-Hebei Urban Agglomeration and Yangtze River Delta Urban Agglomeration,Guangdong-Hong Kong-Macao Greater Bay Area Urban Agglomeration”(No.21JCB052)Beijing Social Science Fund on Decision-Making Advice.
文摘The Beijing-Tianjin-Hebei region,Yangtze River Delta,and Guangdong-Hong Kong-Macao Greater Bay Area and other urban agglomerations are emerging as important drivers of high-quality economic development.This paper establishes an evaluation indicator system to assess the levels of high-quality economic development in these urban agglomerations based on the new development philosophy.Utilizing the CRITIC-Entropy weight method and kernel density estimation method,this paper measures and compares the levels of high-quality economic development in the three urban agglomerations from 2011 to 2020 and analyzes the factors influencing their high-quality development.The findings indicate that all three urban agglomerations exhibit a stable upward trend in high-quality development,with diminishing relative differences among them.From a dimensional perspective,each agglomeration has unique strengths and weaknesses in terms of highquality economic development.The innovation and entrepreneurship level,urbanization,advanced industrial structure,environmental regulation,marketization,and transportation infrastructure play significant roles in fostering high-quality economic development.
