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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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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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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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基于组合权重的基坑支护方案模糊物元优选 被引量:6
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作者 蒋崇春 孟茁超 《湖南城市学院学报(自然科学版)》 CAS 2010年第2期5-9,共5页
针对深基坑支护方案优选决策多属性、确定性与不确定性共存的特点,从安全性、经济性和可行性3个角度出发,综合考虑影响支护方案的定量、非定量指标,选取技术先进性、类似方案成功率、稳定性、成本、工期、地质情况、环境条件和对环境的... 针对深基坑支护方案优选决策多属性、确定性与不确定性共存的特点,从安全性、经济性和可行性3个角度出发,综合考虑影响支护方案的定量、非定量指标,选取技术先进性、类似方案成功率、稳定性、成本、工期、地质情况、环境条件和对环境的影响程度8个指标,建立了基坑支护方案的模型.在评价过程中,引用信息熵所反映数据本身的效用值来计算指标的熵权和层次分析法求得的专家权重来求得综合权重,用方案的各项评价指标及其相应的模糊量值构造复合模糊物元,通过计算与标准模糊物元之间的欧式贴近度来实现方案的排序与择优.以长沙某基坑支护方案为例证明了该方法应用于支护方案优选的有效性和可行性,研究表明该模型可有效地避免权重分配困难的问题,通过评价样本与评价标准之间的远近关系,得出待选方案的欧式贴近度分别为96.7%、84.3%和88.9%,从而选取方案一,进而为基坑支护方案综合评价提供了一种新思路. 展开更多
关键词 基坑支护 方案优选 欧式贴近度(EAD) 模糊物元 层次分析法
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