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太平洋克拉里昂-克利伯顿断裂带嘴刺目线虫多样性

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生态学报 2017年第5期37卷 1630-1638页

作者：张顺林施泉孟凡旭吴敏许学伟王春生国家海洋局第二海洋研究所杭州310012 浙江大学生命科学学院杭州310058

从太平洋深海克拉里昂-克利伯顿断裂带(Clarion-Clipperton fracture zone,简称CC区)4个站位采集的深海沉积物样品中检出26条嘴刺目(Enoplida)线虫个体。综合应用形态学和分子生物学方法,共鉴定嘴刺目线虫6科8属,其中尖口线虫科(Oxystom... 详细信息

从太平洋深海克拉里昂-克利伯顿断裂带(Clarion-Clipperton fracture zone,简称CC区)4个站位采集的深海沉积物样品中检出26条嘴刺目(Enoplida)线虫个体。综合应用形态学和分子生物学方法,共鉴定嘴刺目线虫6科8属,其中尖口线虫科(Oxystominidae)个体数量最多,占总数的57.7%,其次为前感线虫科(Anticomidae,19.2%)、光皮线虫科(Phanodermatidae,7.7%)、钩线虫科(Oncholaimidae,7.7%)、烙线虫科(Ironidae,3.8%)和矛线虫科(Enchelidiidae,3.8%)。科、属组成与相邻站点同期采样所获的线虫近似,而丰度组成比例有所差异。分子生物学方法获得了线虫rRNA基因序列16条,经Gen Bank数据库比对,其与已有的序列相似性范围为94%—99%,以此为依据可确定到科的水平和大部分属的水平(84.6%)。DNA条形码比对结果和形态学鉴定结果有较高一致性,表明分子条形码技术可作为深海线虫鉴定的有效手段。系统发育分析结果显示,基于18S和28S rRNA基因序列,采用不同方法构建系统发育树,其分支结构基本一致;钩线虫科和矛线虫科聚类在一起,光皮线虫科和前感线虫科聚类在一起,显示出彼此间较近的遗传关系。

关键词：嘴刺目线虫多样性系统发育克拉里昂-克利伯顿断裂带

Discrete Differential Calculus on Simplicial Complexes and Constrained Homology

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Chinese Annals of Mathematics,Series B 2023年第4期44卷 615-640页

作者： shiquan REN School of Mathematics and Statistics Henan University

Let V be a finite *** K be a simplicial complex with its vertices in *** this paper,the author discusses some differential calculus on *** constructs some constrained homology groups of K by using the differential calculus on ***,he defines an independence hyper graph to be the complement of a simplicial complex in the complete hypergraph on *** L be an independence hypergraph with its vertices in *** constructs some constrained cohomology groups of L by using the differential calculus on V.

关键词： Simplicial complexes Hypergraphs Chain complexes Homology Differential calculus

Accurate 8-Node Hybrid Hexahedral Elements with Energy-Compatible Stress Modes

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Advances in Applied Mathematics and Mechanics 2010年第3期2卷 333-354页

作者： shiquan Zhang Xiaoping Xie School of Mathematics Sichuan UniversityChengdu 610064China

In this paper,an energy-compatibility condition is used for stress optimization in the derivation of new accurate 8-node hexahedral elements for threedimensional *** of the proposed hybrid method to an enhanced strains method is established,which makes it easy to extend the method to general nonlinear *** tests show that the resultant elements possess high accuracy at coarse meshes,are insensitive to mesh distortions and free from volume locking in the analysis of beams,plates and shells.

关键词： Finite element hybrid stress method Hellinger-Reissner principle locking

Quasi-variational principles of single flexible body dynamics and their applications

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Science China(Physics,Mechanics & Astronomy) 2009年第5期52卷 775-787页

作者： LIANG LiFu LIU shiquan ZHOU JianSheng School of Civil Engineering Harbin Engineering UniversityHarbin 150001China China Sanjiang Space Industry Group Corp Wuhan 430015China

The reasons for studying single flexible body dynamics are that on one hand,it is the basis of flexible multi-body *** the theory of the single flexible body dynamics has been deeply studied,the theory of flexible multi-body dynamics will be researched *** the other hand,it has its unique and important ***-variational principle of non-conservative single flexible body dynamics is established under the cross-link of particle rigid body mechanics and deformable body *** the interceptor as an example,this paper has explained the physical meaning of the quasi-stationary value condition of the quasi-variational principle in non-conservative single flexible body *** the launch of rocket as an example,it has illustrated the features of"one force for two effects"in a single flexible body *** an example of the extending flexible beam coupled with the spacecraft attitude,it has shown the transition from the single flexible body dynamics to the flexible multi-body ***,a number of related problems are discussed.

关键词： variational principle non-conservative system aerospace dynamics flexible multi-body dynamics single flexible body dynamics

The General-Purpose Intelligent Agent

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Engineering 2020年第3期6卷 221-226页

作者： Cewu Lu shiquan Wang Department of Computer Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Flexiv Ltd. Shanghai 201105China

*** In our daily life,we expect smart devices to help us with different kinds of *** this reason,it is necessary to design a variety of robots and related algorithms specifically for different tasks and ***,such a methodology results in smart devices with limited intelligence that fall far below our expectations and fail to adapt to different real-life task *** contrast,if we regard humans as“intelligent agents,”such an agent,given appropriate tools,can perform different manipulation tasks in various *** by this idea,we perceive a need for a generalpurpose intelligent agent(GIA),such that most tasks can be executed by the same agent,which will significantly accelerate the development of intelligent industries and increase the convenience of human *** also believe that,in order to approach the goal of artificial general intelligence[1],a powerful and standard GIA is necessary.

关键词： agent artificial app

MAXIMUM TREES OF FINITE SEQUENCES

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Applied Mathematics(A Journal of Chinese Universities) 1995年第2期10卷 223-228页

作者： WU shiquan Center for Mathematical Sciences Zhejiang University Hangzhou

Let n, s1, s2,..., sn be non-negative integers and M(s1, s2,...,sn) ={(a1, a2,..., a.)| ai is an integer and 0≤ai ≤si for each i}. In this paper, the cardinality of maximum trees of finite sequences in M(s1, s2,..., sn) sn) is obtained, which generalizes some of Frankl's results on families of finite sets with prescribed cardinalities for pairwise intersections.

关键词： Tree of subsets finite sequences tree of finite sequences.

Computational Tools in Weighted Persistent Homology

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Chinese Annals of Mathematics,Series B 2021年第2期42卷 237-258页

作者： shiquan REN Chengyuan WU Jie WU Yau Mathematical Sciences Center Tsinghua UniversityBeijing 100084China Department of Mathematics National University of SingaporeSingapore 119076Singapore Institute of High Performance Computing A*STARSingapore 138632Singapore School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China Center for Topology and Geometry based Technology Hebei Normal University050024China.

In this paper, the authors study further properties and applications of weighted homology and persistent homology. The Mayer-Vietoris sequence and generalized Bockstein spectral sequence for weighted homology are introduced. For applications, the authors show an algorithm to construct a filtration of weighted simplicial complexes from a weighted network. They also prove a theorem to calculate the mod p^(2) weighted persistent homology provided with some information on the mod p weighted persistent homology.

关键词： Algebraic topology Persistent homology Weighted persistent homology Bockstein spectral sequence

Dynamics of a stochastic three-species competitive model with Levy jumps

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International Journal of Biomathematics 2018年第5期11卷 285-308页

作者： Yongxin Cao shiquan Tian College of Science Civil Aviation University of China Tianjin 300300 P. R. China

This paper is concerned with a three-species competitive model with both white noises and Levy noises. We first carry out the almost complete parameters analysis for the model and establish the critical value between persistence in the mean and extinction for each species. The sufficient criteria for stability in distribution of solutions are obtained. Finally, numerical simulations are carried out to verify the theoretical results.

关键词： Stochastic competitive model Levy jumps extinction persistence in the mean stability in distribution.

A Künneth Formula for Finite Sets

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Chinese Annals of Mathematics,Series B 2021年第6期42卷 801-812页

作者： Chong WANG shiquan REN Jian LIU School of Mathematics Renmin University of ChinaBeijing 100872China Department of Mathematics and Statistics Cangzhou Normal UniversityCangzhou 061000HebeiChina School of Mathematics and Statistics Henan UniversityKaifeng 475001HenanChina School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050024China

In this paper,the authors define the homology of sets,which comes from and contains the ideas of path homology and embedded ***,A Kunneth formula for sets associated to the homology of sets is given.

关键词： Künneth formula Finite set Principal ideal domain Cartesian product Free R-module