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Estimating the Degree of Earthquake Risk from Fault Characteristics
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作者 Hou Jianjun Bai Taixu Liang Haihua Han Mukang Department of Geology, Peking University, Beijing 100871 Ollier C. D. Center for Resource and Environmental Studies, Australia National University, Canberra ACT 0200, Australia 《Journal of Earth Science》 SCIE CAS CSCD 1998年第3期16-19,共4页
A theoretical model considering the relationship between fault characteristics and tectonic stress is proposed to quantify earthquake risk degree. The model is applied in practice to the fault along the southern margi... A theoretical model considering the relationship between fault characteristics and tectonic stress is proposed to quantify earthquake risk degree. The model is applied in practice to the fault along the southern margin of Weihe basin in Shaanxi Province, Northwestern China and fitted well with reality. 展开更多
关键词 earthquake risk degree fault movement probability fault unstable degree earthquake time approach degree.
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Analysis on the Origin and Phylogenetic Status of Tong Sheep Using 12 Blood Protein and Nonprotein Markers
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作者 孙伟 常洪 +5 位作者 杨章平 耿荣庆 角田健司 任战军 陈宏宇 Musa H.Hussein 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第12期1097-1105,共9页
This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene co... This study is based on the Tong sheep obtained by the random sampling method of typical colonies in the central area of Baishui County in Shaanxi Province, China. An investigation was undertaken to clarify the gene constitution of blood protein and nonprotein types of Tong sheep. Twelve genetic markers were examined by starch-gel electrophoresis and cellulose acetate electrophoresis. Polymorphism in Tong sheep was found at the following 10 loci, transferrin (Tf), alkaline phosphatase (Alp), leucine aminopeptidase (Lap), arylesterase (Ary-Es), hemoglobin-β (Hb-β), X-protein (X-p), carbonic anhydrase (CA), catalase (Cat), malate dehydrogenase (MDH), and lysine (Ly), whereas, albumin (A1) and postalbumin (Po) loci were monomorphic. Genetic approach degree method and phylogenetic relationship clustering method were used to judge the origin and phylogenetic status of Tong sheep. Results from both methods maintained that Tong sheep belonged to the "Mongolia group", and Mongolia sheep was the origin of Tong sheep. This was also supported by the history of Tong sheep breeding. Compared to the phylogenetic relationship clustering method, the genetic approach degree method was more reliable for the extraction from East and South of Central Asia, and was more effective in reflecting the breeding course of Tong sheep. 展开更多
关键词 Tong sheep ORIGIN phylogenetic status genetic approach degree phylogenetic relationship clustering
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Optimizing selection of bridge raft based on fuzzy matter-element model and combination weighting
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作者 Li Feng Shao Fei +1 位作者 Wang Jianping Li Zhigang 《Engineering Sciences》 EI 2012年第1期61-64,96,共5页
It' s a necessary selection to support the maneuver across Yangtze River by floating bridge constructed by portable steel bridge and civilian ships. It is a comprehensive index for the scheme of bridge raft, containi... It' s a necessary selection to support the maneuver across Yangtze River by floating bridge constructed by portable steel bridge and civilian ships. It is a comprehensive index for the scheme of bridge raft, containing a variety of technical factors and uncertainties. The optimization is the selection in the constructing time, quantity of equipments and man power. Based on the calculation result of bridge rafts, an evaluating system is established, consisting of index of spacing between interior bays, raft length, truss numbers, operation difficulty and maximal bending stress. A fuzzy matter element model of optimizing selection of bridge rafts was built up by combining quantitative analysis with qualitative analysis. The method of combination weighting was used to calculate the value of weights index to reduce the subjective randomness. The sequence of schemes and the optimization resuh were gained finally based on euclid approach degree. The application result shows that it is simple and practical. 展开更多
关键词 bridge raft optimizing selection fuzzy matter-element combination weighting euclid approach degree
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Vertex Cover Optimization Using a Novel Graph Decomposition Approach
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作者 Abdul Manan Shahida Bashir Abdul Majid 《Computers, Materials & Continua》 SCIE EI 2022年第10期701-717,共17页
The minimum vertex cover problem(MVCP)is a well-known combinatorial optimization problem of graph theory.The MVCP is an NP(nondeterministic polynomial)complete problem and it has an exponential growing complexity with... The minimum vertex cover problem(MVCP)is a well-known combinatorial optimization problem of graph theory.The MVCP is an NP(nondeterministic polynomial)complete problem and it has an exponential growing complexity with respect to the size of a graph.No algorithm exits till date that can exactly solve the problem in a deterministic polynomial time scale.However,several algorithms are proposed that solve the problem approximately in a short polynomial time scale.Such algorithms are useful for large size graphs,for which exact solution of MVCP is impossible with current computational resources.The MVCP has a wide range of applications in the fields like bioinformatics,biochemistry,circuit design,electrical engineering,data aggregation,networking,internet traffic monitoring,pattern recognition,marketing and franchising etc.This work aims to solve the MVCP approximately by a novel graph decomposition approach.The decomposition of the graph yields a subgraph that contains edges shared by triangular edge structures.A subgraph is covered to yield a subgraph that forms one or more Hamiltonian cycles or paths.In order to reduce complexity of the algorithm a new strategy is also proposed.The reduction strategy can be used for any algorithm solving MVCP.Based on the graph decomposition and the reduction strategy,two algorithms are formulated to approximately solve the MVCP.These algorithms are tested using well known standard benchmark graphs.The key feature of the results is a good approximate error ratio and improvement in optimum vertex cover values for few graphs. 展开更多
关键词 Combinatorial optimization graph theory minimum vertex cover problem maximum independent set maximum degree greedy approach approximation algorithms benchmark instances
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