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Elevation as a selective force on mitochondrial respiratory chain complexes of the Phrynocephalus lizards in the Tibetan plateau
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作者 Yuanting JIN Débora Y.C.BRANDT +3 位作者 Jiasheng LI Yubin WO Haojie TONG Vladimir SHCHUR 《Current Zoology》 SCIE CAS CSCD 2021年第2期191-199,共9页
Animals living in extremely high elevations have to adapt to low temperatures and low oxygen availability(hypoxia),but the underlying genetic mechanisms associated with these adaptations are still unclear.The mitochon... Animals living in extremely high elevations have to adapt to low temperatures and low oxygen availability(hypoxia),but the underlying genetic mechanisms associated with these adaptations are still unclear.The mitochondrial respiratory chain can provide>95%of the ATP in animal cells,and its efficiency is influenced by temperature and oxygen availability.Therefore,the respiratory chain complexes(RCCs)could be important molecular targets for positive selection associated with respiratory adaptation in high-altitude environments.Here,we investigated positive selection in 5 RCCs and their assembly factors by analyzing sequences of 106 genes obtained through RNA-seq of all 15 Chinese Phrynocephalus lizard species,which are distributed from lowlands to the Tibetan plateau(average elevation>4,500 m).Our results indicate that evidence of positive selec-tion on RCC genes is not significantly different from assembly factors,and we found no difference in selective pressures among the 5 complexes.We specifically looked for positive selection in line-ages where changes in habitat elevation happened.The group of lineages evolving from low to high altitude show stronger signals of positive selection than lineages evolving from high to low elevations.Lineages evolving from low to high elevation also have more shared codons under positive selection,though the changes are not equivalent at the amino acid level.This study advan-ces our understanding of the genetic basis of animal respiratory metabolism evolution in extreme high environments and provides candidate genes for further confirmation with functional analyses. 展开更多
关键词 ELEVATION positive selection REPTILE PLATEAU respiratory chain complexes
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CRYSTAL STRUCTURE OF LONG CHAIN COMPLEX OF [Cu(TTA)(4,4'-BIPYRIDINE)]_n
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作者 Ming Xing LI Zhong Zhi WU +3 位作者 Zheng XU Xiao Zeng YOU Zheng Chao DONG Guo Cong GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第10期819-820,共2页
The crystal structure of[Cu(2-thienoyl-trifluoroacetone)(4,4—bipyridine)]_n was determined by X-ray diffraction analysis. The crystal belongs to monoclinie with the space group C2/c, Mr=440.91, a=9.640(5) A, b=24.97(... The crystal structure of[Cu(2-thienoyl-trifluoroacetone)(4,4—bipyridine)]_n was determined by X-ray diffraction analysis. The crystal belongs to monoclinie with the space group C2/c, Mr=440.91, a=9.640(5) A, b=24.97(1) A, c=16.032(7) A, β=106.76(3)°,V=3695(3) A^3, Z=8, Dc=1.58g/cm^3, F(000)=1776. Final R and Rw are 0.062 and 0.069, respectively. The local coordination geometry around Cu(I) ion is a distorted tetrahedron. Cu(TTA) are linked with 4,4-bipyridine, forming long chain in the crystal. 展开更多
关键词 TTA BIPYRIDINE CRYSTAL STRUCTURE OF LONG chain complex OF CU
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A Global Reduction Based Algorithm for Computing Homology of Chain Complexes
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作者 Madjid Allili David Corriveau 《Advances in Pure Mathematics》 2016年第3期113-137,共25页
In this paper, we propose a new algorithm to compute the homology of a finitely generated chain complex. Our method is based on grouping several reductions into structures that can be encoded as directed acyclic graph... In this paper, we propose a new algorithm to compute the homology of a finitely generated chain complex. Our method is based on grouping several reductions into structures that can be encoded as directed acyclic graphs. The organized reduction pairs lead to sequences of projection maps that reduce the number of generators while preserving the homology groups of the original chain complex. This sequencing of reduction pairs allows updating the boundary information in a single step for a whole set of reductions, which shows impressive gains in computational performance compared to existing methods. In addition, our method gives the homology generators for a small additional cost. 展开更多
关键词 Homology Algorithm chain complex Homology Generators
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Syntheses, Crystal Structures and Properties of Two New W-Ag 1D Chain Complexes: [W_2Ag_2S_8·Ca(DMF)_6]_n and [WAgS_4·Na(DMF)_3]_n 被引量:1
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作者 LIYa-Min XIASheng-Qing ZHANGJian-Jun WUXin-Tao WANGLong-Sheng DUWen-Xin HUSheng-Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第6期716-722,共7页
Two new complexes, [W2Ag2S8?Ca(DMF)6]n 1 and [WAgS4?Na(DMF)3]n 2, have been synthesized and characterized. Single-crystal X-ray analyses show both 1 and 2 have {WAgS4}n anion linear chains, but 1 has a discrete [Ca(DM... Two new complexes, [W2Ag2S8?Ca(DMF)6]n 1 and [WAgS4?Na(DMF)3]n 2, have been synthesized and characterized. Single-crystal X-ray analyses show both 1 and 2 have {WAgS4}n anion linear chains, but 1 has a discrete [Ca(DMF)6]2+ cation while 2 is a linear chain. UV-Visible-Near-IR spectroscopy data show that the bandgaps of the two complexes are 1.86 and 1.99 eV, respectively. Electrical conductivity measurements reveal the conductivities of 1 and 2 are 10?7 and 10?8 Scm?1, respectively and they exhibit thermally activated temperature depen- dence, which may be attributed to semiconductors. 展开更多
关键词 W/Ag/S complexes linear chain conductivity
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Synthesis and Crystal Structure of One-dimensional Chain Complexes [K(18-C-6)]_2[M(mnt)_2](M=Zn,Hg)
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作者 WANGDa-qi HEGuo-fang +1 位作者 QIULin-lin DOUJian-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第3期263-268,共6页
The reactions of 18 crown 6 with each of K 2(M=Zn, Hg; mnt=1,2 dicyanoethene 1,2 dithiolate, C 2S 2(CN) 2- 2) were studied and novel complexes [K(18 C 6)] 2[Zn(mnt) 2](1) and [K(18 C 6)] 2[Hg(mnt)... The reactions of 18 crown 6 with each of K 2(M=Zn, Hg; mnt=1,2 dicyanoethene 1,2 dithiolate, C 2S 2(CN) 2- 2) were studied and novel complexes [K(18 C 6)] 2[Zn(mnt) 2](1) and [K(18 C 6)] 2[Hg(mnt) 2](2) were characterized by elemental analysis, IR spectrum and X ray diffraction analysis. Complex 1 displays a one dimensional chain of [K(18 C 6)] 2[Zn(mnt) 2] bridged by K O interactions between adjacent [K(18 C 6)] + units. Complex 2 is also a one dimensional chain of [K(18 C 6)] 2[Hg(mnt) 2] bridged by K...S weak interactions between adjacent [K(18 C 6)] + and [Hg(mnt) 2] 2- . 展开更多
关键词 One dimensional chain Crown ether mnt complex 18 Crown 6 Crystal structure
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A 1D Double Stranded Chain Complex Based on Barium Ion and 1,3,5-Triazine
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作者 曹曼丽 张秀莲 尹伟 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第4期499-504,共6页
A new coordination compound [Ba(OBPT)2(H2O)2]·H2O was obtained at room temperature by the reaction of 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol(HOBPT) with BaCl2.It was characterized by elemental analysis,FTI... A new coordination compound [Ba(OBPT)2(H2O)2]·H2O was obtained at room temperature by the reaction of 4,6-bis(2-pyridyl)-1,3,5-triazin-2-ol(HOBPT) with BaCl2.It was characterized by elemental analysis,FTIR,TG analysis,powder X-ray diffraction analysis and single-crystal X-ray diffraction analysis.The complex crystallizes in the monoclinic P21/n space group,with a = 16.325(1),b = 6.7977(5),c = 24.164(2) ,β = 104.009(1),V = 2601.8(3) 3,Z =4,C26H22BaN10O5,Mr = 691.88,Dc = 1.766 g/cm3,F(000) = 1376 and μ(MoKα) = 1.587 mm-1.The final R = 0.0282 and wR = 0.0724 for 5095 observed reflections with I 〉 2σ(I) and R = 0.0312 and wR = 0.0744 for all data.In the complex,the barium ion is ten-coordinated with six nitrogen atoms from two ligands,two deprotonated hydroxyl oxygen atoms from another two ligands and two coordinated water molecules to form a double stranded chain.The extensive supramolecular interac-tions lead to the formation of an infinite 2D framework. 展开更多
关键词 complex 1 3 5-triazine BARIUM 1D chain
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Synthesis, Structure, and Luminescent and Dielectric Properties of a Novel 1D Chain Zinc(Ⅱ) Complex {[Zn(DCImPyO)·(H_2O)_2·]·H_3O}_n 被引量:7
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作者 陈立庄 汪芳明 曹星星 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第10期1417-1422,共6页
Under hydrothermal conditions, 4-(4,5-dicarboxy-lH-imidazol-2-yl)pyridine 1-oxide (H3DCImPyO) reacted with ZnC12 to give the 1D chain complex {[Zn(DCImPyO)·(H2O)2·]·H3O}n (1). Single-crystal ... Under hydrothermal conditions, 4-(4,5-dicarboxy-lH-imidazol-2-yl)pyridine 1-oxide (H3DCImPyO) reacted with ZnC12 to give the 1D chain complex {[Zn(DCImPyO)·(H2O)2·]·H3O}n (1). Single-crystal X-ray determination shows that complex 1 crystallizes in the monoclinic system, space group P21/c with a = 9.488(2), b = 13.247(3), c = 12.959(4) A, β = 126.716(19)°, Z = 4, V= 1305.6(6)/k3, C10H11N3O8Zn, Dc = 1.865 g/cm3, Mr = 366.61, 2(MoKa) = 0.71073 A, μ= 1.930 mm1, F(000) = 744, R = 0.0472 and wR = 0.1487. Fluorescent analysis showed an intense emission band at 422 nm when the exciting radiation was set at 378 nm. Dielectric constant of complex 1 was measured at different frequencies with temperature variation. 展开更多
关键词 ID chain ZINC complex HYDROTHERMAL LUMINESCENT PERMITTIVITY
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Synthesis,Structure and Dielectric Properties of a Novel 1D Chain Bismuth(Ⅲ) Complex[(C_6H_6NO_2)_2·(BiCl_5)·2H_2O]_n 被引量:3
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作者 陈立庄 高延敏 +1 位作者 邹俊 黄美娜 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第2期284-288,共5页
Under hydrothermal conditions,isonicotinic acid reacted with BiCl 3 to give 1D zigzag chain complex [(C 6 H 6 NO 2) 2 ·(BiCl 5)·2H 2 O] n (1).Single-crystal X-ray determination shows that compound 1 cr... Under hydrothermal conditions,isonicotinic acid reacted with BiCl 3 to give 1D zigzag chain complex [(C 6 H 6 NO 2) 2 ·(BiCl 5)·2H 2 O] n (1).Single-crystal X-ray determination shows that compound 1 crystal-lizes in the monoclinic system,space group C2/c with a=13.115(3),b=19.957(4),c=7.9374(16),β=97.45(3)°,Z=4,V=2060.0(8) 3,C 12 H 16 BiCl 5 N 2 O 6,D c=2.162 g/cm 3,M r=670.50,λ(MoKa)=0.71073,μ=9.237 mm-1,F(000)=1272,R=0.0208 and wR=0.0503.Dielectric constant of compound 1 was measured at different conditions.Measurements on the dielectric properties of 1 showed that the 1D chain coordination polymer exhibited a dipolar chain relaxation process and a relatively high dielectric constant. 展开更多
关键词 1D chain BISMUTH complex HYDROTHERMAL PERMITTIVITY
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One-dimensional Chain Dibenzo-18-crown-6 Complex: [K(DB18-C-6)]_2[Pt(SCN)_6]·2H_2O·C_2H_4Cl_2 Assembled by Cation-π Interactions 被引量:1
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作者 ZHUYue-hua DUMao-xi +2 位作者 LIDa-cheng WANGDa-qi DOUJian-min 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期123-126,共4页
关键词 One-dimensional chain Crown ether complex Cation-π interactions Synthesis and crystal structure
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A MEASURE OF SUPPLY CHAIN COMPLEXITY INCORPORATING VIRTUAL ARCS
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作者 Julie Drzymalski 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2015年第4期486-499,共14页
Increased globalization, as well as the ability to have virtual supply chain partners, has had numerous effects on supply chains. While some of these effects are positive, making more resilient supply chains, there ar... Increased globalization, as well as the ability to have virtual supply chain partners, has had numerous effects on supply chains. While some of these effects are positive, making more resilient supply chains, there are also the negative effects of scale ~nd complexity, making these supply chains more challenging than ever to manage. Having a means to measure the complexity is crucial for today's managers to make more informed decisions. This measure must not only account for the number of arcs, but the amount of information and material carried on it, as well as incorporate the benefit that virtual arcs add to the network by increasing efficiency and reducing information, product and financial transfer costs and time. This research utilizes newer models in network clustering and complexity theory to make them applicable to supply chains and creates a new, practical approach to measuring supply chain complexity which can be easily implemented by practitioners. 展开更多
关键词 Supply chain complexITY CLUSTERING virtual networks
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Structure of the Heterobimetallic Linear-Chain Polymeric Complex [NH_4]_n [WAgS_4]_n and Influence of Cationic Valence State on Configurations of Polymeric W/Ag/S Complexes
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作者 HUANG Qun WU Xin-Tao LU Jia-Xi(State Key Laboratory of Structural Chemistry, Fujian Institute of Research onthe Structure of Matter, the Chinese Academy of Sciences, Fuzhou 350002) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1997年第4期253-257,共5页
The title complex [NH4]n [WAgS4]n crystallizes in the tetragonalspace group I4 with crystallographic parameters: a = b = 7. 994 (2 ), c = 5. 855 (2 ):A,V = 373. g(2) A3, Z=2, Dc= 3. 89 g/cm3, F(000) = 392, μ= 19. 27 ... The title complex [NH4]n [WAgS4]n crystallizes in the tetragonalspace group I4 with crystallographic parameters: a = b = 7. 994 (2 ), c = 5. 855 (2 ):A,V = 373. g(2) A3, Z=2, Dc= 3. 89 g/cm3, F(000) = 392, μ= 19. 27 mm-l , A(MoKα) = 0. 71069, Mr = 438. 01, and the convergence factors R = 0. 045, Rw =0. 055 for 341 observed reflections (I>3σ(I)). The anion structure can be viewed as apolymeric single chain consisting of unlimited extended rhombic fragruents of -AgS2W-which are alternately perpendicular to each other. Additionally, influence of di- and tri-valent complex cations on the assembIy of WS2-4 and Ag+ is briefly discussed. 展开更多
关键词 tungsten complex silver complex POLYMERIC LINEAR-chain complex crystal STRUCTURE
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Empirical topological investigation of practical supply chains based on complex networks
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作者 廖好 沈婧 +2 位作者 吴兴桐 陈博奎 周明洋 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第11期144-150,共7页
The industrial supply chain networks basically capture the circulation of social resource, dominating the stability and efficiency of the industrial system. In this paper, we provide an empirical study of the topology... The industrial supply chain networks basically capture the circulation of social resource, dominating the stability and efficiency of the industrial system. In this paper, we provide an empirical study of the topology of smartphone supply chain network. The supply chain network is constructed using open online data. Our experimental results show that the smartphone supply chain network has small-world feature with scale-free degree distribution, in which a few high degree nodes play a key role in the function and can effectively reduce the communication cost. We also detect the community structure to find the basic functional unit. It shows that information communication between nodes is crucial to improve the resource utilization. We should pay attention to the global resource configuration for such electronic production management. 展开更多
关键词 China supply chain networks complex networks data science network science
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Mass spectrometry assisted assignments of binding and cleavage sites of Zn(Ⅱ)complex towards oxidized insulin B chain
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作者 Jiang Jiang Qiong Jie Wu +2 位作者 Xiang Yang Cai Long Gen Zhu Wen Ji Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第1期71-75,共5页
The electrospray ionization mass spectrometry investigation showed that the binding sites of [ZnL]^2+, where L is 2-[bis(2- aminoethyl)amino]ethanol, with oxidized insulin B chain are Phel, His5 and Arg22, which le... The electrospray ionization mass spectrometry investigation showed that the binding sites of [ZnL]^2+, where L is 2-[bis(2- aminoethyl)amino]ethanol, with oxidized insulin B chain are Phel, His5 and Arg22, which lead to the selective cleavages of the peptide bonds at Phe1-Val2, His5-Leu6, Glu21-Arg22, and Arg22-Gly23 of oxidized insulin B chain. 展开更多
关键词 Oxidized insulin B chain Zn(Ⅱ) complex Mass spectrometry Hydrolytic cleavage
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Crystal Structure, Thermal Analysis and Theoretical Calculation of a One-dimensional Chain Complex [Zn(dafo)_2(H2O)_2](NO_3)_2
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作者 张荣兰 赵建社 +2 位作者 高新 史启祯 何水样 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2004年第8期837-840,共4页
A novel one-dimensional chain complex [Zn(dafo)2(H2O)2](NO3)2 was obtained when we tried synthesizing a mixed ligand supramolecular compound of Zinc(II) with dafo and o-phthalic acid. Its structure was determined by ... A novel one-dimensional chain complex [Zn(dafo)2(H2O)2](NO3)2 was obtained when we tried synthesizing a mixed ligand supramolecular compound of Zinc(II) with dafo and o-phthalic acid. Its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to triclinic system, P-1 space group. The crystallo- graphic data: a=0.6989(4) nm, b=0.8281(5) nm, c=1.0231(5) nm, α=94.934(5)°, β=91.366(7)°, γ=99.820(7)°, V=0.5809(5) nm3, Z=1, F(000)=300, Mr=589.78, Dc=1.686 g/cm3, μ(Mo Kα)=1.130 mm-1, R1=0.0521, wR2 =0.1096. The analysis of the crystal structure indicates that the compound has a one-dimensional chain structure which is formed by hydrogen bonds. The constitutes of the title complex were proved by elemental analysis, IR spectra and thermal analysis. On the basis of the experimentation, the complex was calculated by DFT-B3LYP/LANL2DZ in Gaussian-98w also. 展开更多
关键词 one-dimensional chain structure zinc(II) complex crystal structure thermal analysis theoretical calculation
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Hydrothermal Synthesis,Crystal Structure and Thermal Properties of a Novel Samarium Complex with 1D Nano-chain Structure
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作者 LI Ya-Juan LIANG Qing +3 位作者 SONG Hui-hua JIA Mi-ying SHI Shi-Kao ZHANG Jian-jun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第1期118-121,共4页
1 Introduction The design and construction of metal-organic polymers has been a field of rapid growth in materials chemistry because of their intriguing topologies and potential applications as functional materials. ... 1 Introduction The design and construction of metal-organic polymers has been a field of rapid growth in materials chemistry because of their intriguing topologies and potential applications as functional materials. In this regard, every effort has been devoted to the deliberate design and control of self-assembly infinite coordination networks via selecting the chemistry structures of ligands, Multidentate carboxylate ligands are widely adopted for construction of coordination frameworks due to their rich coordination modes. 展开更多
关键词 Samarium complex 1D Nano-chain structure Hydrothermal synthesis Thermal analysis
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基于复杂网络的洪涝灾害链风险评估 被引量:5
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作者 高玉琴 徐诺 +2 位作者 汪键 王丽君 刘彤 《水资源保护》 北大核心 2025年第2期115-122,共8页
为研究洪涝灾害演化过程对流域居民生活和社会经济的影响,从灾害链和复杂网络视角对洪涝灾害链演化风险开展评估。通过收集洪涝灾害典型案例,结合事件树分析法,搭建了洪涝灾害链演化网络。基于贝叶斯网络和网络传播模型,构建了洪涝灾害... 为研究洪涝灾害演化过程对流域居民生活和社会经济的影响,从灾害链和复杂网络视角对洪涝灾害链演化风险开展评估。通过收集洪涝灾害典型案例,结合事件树分析法,搭建了洪涝灾害链演化网络。基于贝叶斯网络和网络传播模型,构建了洪涝灾害链风险评估模型,并应用于秦淮河流域。结果表明:洪涝灾害链综合风险由节点风险累积或叠加构成;秦淮河流域“2016·7”洪涝灾害链综合风险水平在洪涝灾害发生后约103 h达极大值,约173 h达第二峰值,综合风险水平约为原生洪涝风险的7倍;公路事故、供排水事故、生态环境破坏事故、水污染事故为关键节点,洪涝灾害→水土流失灾害→水污染事故→生态环境破坏事故为关键传播边,通过对关键节点加强监测应对,对关键链条进行阻截断链,可有效减灾降损。 展开更多
关键词 洪涝灾害 灾害链 复杂网络 事件树分析法 贝叶斯网络 秦淮河流域
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科技战略供应链的基本特征与关键科学问题 被引量:3
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作者 杨善林 李霄剑 +2 位作者 莫杭杰 张强 唐孝安 《中国管理科学》 北大核心 2025年第1期1-13,共13页
无论是原子弹和人造地球卫星等高端复杂产品的制造,还是登陆月球和火箭回收等高度综合性技术工程,都是十分复杂的系统性实践过程。为了支撑高端复杂产品制造等系统工程的颠覆性创新发展,本文提出了科技战略供应链这一基本概念。深入研... 无论是原子弹和人造地球卫星等高端复杂产品的制造,还是登陆月球和火箭回收等高度综合性技术工程,都是十分复杂的系统性实践过程。为了支撑高端复杂产品制造等系统工程的颠覆性创新发展,本文提出了科技战略供应链这一基本概念。深入研究科技战略供应链的形成与发展过程,能够回答高端复杂产品是如何从无到有的、如何发展演进的、根本动力是什么、有哪些基本规律等核心科学问题,从而促进高端复杂产品的原始创造和创新发展。本文首先回顾了高端复杂产品制造等复杂系统性实践过程;其次从科学、技术、工程、产业之间供求关系的供应链特征界定了科技战略供应链基本概念;然后在总结典型科技战略供应链发展进化过程基本特征的基础上,深入探讨了科技战略供应链的形成机理与动态演化、要素空间与协同优化、韧性设计与风险管控、运行机制与效率提升等四大科学问题;最后从创新人才、创新生态、尖端科技、主导企业、管理机制等方面给出了构建科技战略供应链的战略对策,以期推动我国科技战略供应链建设,助力我国科技与经济高质量发展。 展开更多
关键词 科技战略供应链 高端复杂产品 系统工程方法论 供应链管理理论
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Discrete decision model and multi-agent simulation of the Liang Zong two-chain hierarchical organization in a complex project
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作者 MAI Qiang ZHAO Yueqiang AN Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第2期311-320,共10页
Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain an... Different from the organization structure of complex projects in Western countries, the Liang Zong hierarchical organization structure of complex projects in China has two different chains, the chief-engineer chain and the general-director chain,to handle the trade-off between technical and management decisions. However, previous works on organization search have mainly focused on the single-chain hierarchical organization in which all decisions are regarded as homogeneous. The heterogeneity and the interdependency between technical decisions and management decisions have been neglected. A two-chain hierarchical organization structure mapped from a real complex project is constructed. Then, a discrete decision model for a Liang Zong two-chain hierarchical organization in an NK model framework is proposed. This model proves that this kind of organization structure can reduce the search space by a large amount and that the search process should reach a final stable state more quickly. For a more complicated decision mechanism, a multi-agent simulation based on the above NK model is used to explore the effect of the two-chain organization structure on the speed, stability, and performance of the search process. The results provide three insights into how, compared with the single-chain hierarchical organization, the two-chain organization can improve the search process: it can reduce the number of iterations efficiently; the search is more stable because the search space is a smoother hill-like fitness landscape; in general, the search performance can be improved.However, when the organization structure is very complicated, the performance of a two-chain organization is inferior to that of a single-chain organization. These findings about the efficiency of the unique Chinese-style organization structure can be used to guide organization design for complex projects. 展开更多
关键词 complex project two-chain hierarchical organization discrete decision model multi-agent simulation
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基于复杂网络与数值模拟的暴雨-洪水-泥石流灾害链分析
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作者 杨海波 李梦雨 +2 位作者 蔡迎春 邓宇 李军华 《人民黄河》 北大核心 2025年第7期124-130,共7页
暴雨灾害会引发山洪及泥石流等次生灾害,形成复杂的灾害链,对社会经济和自然生态系统造成重大威胁。现有研究对多灾害节点之间的交互关系及其叠加风险的探索尚显不足。为解决这一问题,结合复杂网络理论与FLO-2D数值模拟技术,构建了一种... 暴雨灾害会引发山洪及泥石流等次生灾害,形成复杂的灾害链,对社会经济和自然生态系统造成重大威胁。现有研究对多灾害节点之间的交互关系及其叠加风险的探索尚显不足。为解决这一问题,结合复杂网络理论与FLO-2D数值模拟技术,构建了一种针对暴雨-洪水-泥石流灾害链的分析框架,并以河南省栾川县柿树沟为研究区域,分析河南郑州“7·20”特大暴雨灾害背景下的灾害链动态演化特征。研究结果表明:1)数值模拟结果显示泥石流的最大流速可达6.56 m/s,最大堆积深度为7.30 m,高、中、低危险区占比分别为3.61%、17.65%、78.74%;2)排水设施损坏或堵塞、电力设施损坏、内涝积水、车辆被淹、泥石流、河水倒灌是灾害链网络的关键节点;3)河水倒灌→内涝积水、内涝积水→车辆被淹、内涝积水→电力设施损坏、河堤毁坏→河道堵塞、车辆被淹→人员伤亡是灾害链网络的关键边。从动态演化的视角识别灾害链中的关键节点和关键边,深入解析多灾害节点之间的交互机制,可为灾害风险评估、防灾减灾措施优化及应急管理提供科学依据。 展开更多
关键词 暴雨-洪水-泥石流灾害链 复杂网络 FLO-2D 关键节点 关键边
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纺织服装上市公司产业链特征研究 被引量:1
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作者 张立杰 田赛 金瑞娟 《毛纺科技》 北大核心 2025年第5期102-109,共8页
为分析我国纺织服装产业链网络特征及健壮性,基于国内纺织服装上市公司报表数据,运用复杂网络分析方法构建了纺织服装上市公司产业链关联网络。研究发现:纺织服装上市公司产业链中化纤产业上市公司合作伙伴最多,服装产业上市公司覆盖产... 为分析我国纺织服装产业链网络特征及健壮性,基于国内纺织服装上市公司报表数据,运用复杂网络分析方法构建了纺织服装上市公司产业链关联网络。研究发现:纺织服装上市公司产业链中化纤产业上市公司合作伙伴最多,服装产业上市公司覆盖产业链范围最大;纺织服装上市公司产业链在结构上具有小世界特征且存在枢纽节点;运用社区发现算法分析纺织服装上市公司产业链分布特征,发现不同区域基本形成了较完整的产业链体系,长三角地区与广东、福建等沿海区域是纺织服装产业链的集中和优势区域;健壮性分析发现,动态蓄意攻击,尤其是蓄意攻击影响力较大的关键性上市公司,对纺织服装上市公司产业链的影响最大。 展开更多
关键词 纺织服装产业链 上市公司 产业链特征 复杂网络
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