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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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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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新质生产力驱动应急供应链韧性提升的组态路径研究
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作者 米俊 董丹琪 +1 位作者 王迪 张琪 《经济问题》 北大核心 2026年第2期69-79,共11页
新质生产力通过科技创新和数字化转型,成为推动应急供应链韧性提升的重要着力点。基于复杂适应系统和资源编排理论,运用模糊集定性比较分析方法(fsQCA),从组织人力资源、外部环境条件和技术赋能水平3个方面选取指标,以组态视角探究新质... 新质生产力通过科技创新和数字化转型,成为推动应急供应链韧性提升的重要着力点。基于复杂适应系统和资源编排理论,运用模糊集定性比较分析方法(fsQCA),从组织人力资源、外部环境条件和技术赋能水平3个方面选取指标,以组态视角探究新质生产力赋能应急供应链韧性提升的多维实现路径。研究发现:(1)劳动者能力、组织机构支撑、产业发展、绿色环保、创新研发能力和数字化水平均不能单独作为必要条件增强应急供应链韧性。(2)产生高水平应急供应链韧性的组态类型为组织主导高效赋能型、技术环境双轮驱动型、组织环境协同共生型、资源要素禀赋组合型,并验证了新质生产力影响因素的不同组合方式以“殊途同归”方式提升应急供应链韧性。(3)区域异质性明显,东、中、西和东北部地区的组态路径分别为“东部—技术赋能资源型”“中部—组织环境协同型”“西部—技术环境双轮驱动型”“东北部—组织主导高效赋能型”。据此,从强化应急供应链技术应用、优化资源配置策略和深化区域精准施策提出对策建议,为应急供应链的高效智能化发展提供参考。 展开更多
关键词 新质生产力 应急供应链韧性 复杂适应系统理论 资源编排理论
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基于复杂网络的山地型区域洪涝灾害链风险评估——以北京市门头沟区为例
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作者 卢兴超 徐宗学 +2 位作者 陈浩 叶婉露 王乾勋 《水科学进展》 北大核心 2026年第1期94-106,共13页
揭示山地型城市洪涝灾害链的时空演变机制,解析灾害链的级联效应,量化灾害链的风险水平,可为山地型区域灾害链断链减灾提供技术支撑。以北京市门头沟区历史洪涝灾害和典型“23·7”特大暴雨事件为例,建立山地型区域洪涝灾害链风险... 揭示山地型城市洪涝灾害链的时空演变机制,解析灾害链的级联效应,量化灾害链的风险水平,可为山地型区域灾害链断链减灾提供技术支撑。以北京市门头沟区历史洪涝灾害和典型“23·7”特大暴雨事件为例,建立山地型区域洪涝灾害链风险评估模型,厘清灾害链时空演变关系,评估灾害链风险大小,辨析洪涝灾害链和承灾系统的鲁棒性,提出基于节点防护与重要路径阻断的工程措施和基于灾害监测模拟与避险救援的非工程措施。结果表明:门头沟区洪涝灾害链中城市洪涝(C11)和交通中断(E13)为关键节点,以经济财产损失(G13)为核心的边是灾害链系统的脆弱路径,且是风险爆发的关键出口;灾害链的综合风险值为23.909,其中节点风险贡献80.4%;在采取防灾措施情况下,承灾系统鲁棒性增强,灾害链风险降低,二者呈现负相关关系。借助复杂网络模型厘清山地型城市洪涝灾害链的复杂性,识别关键节点和脆弱边,有助于制定针对性的灾害防控策略和措施。 展开更多
关键词 洪涝灾害链 风险评估 复杂网络 节点 脆弱边 鲁棒性 山地型区域
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Synchronization of spatiotemporal chaos in complex networks via backstepping
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作者 柴元 吕翎 陈立群 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期131-137,共7页
A backstepping approach is proposed for the synchronization of chain networks of multi-spatiotemporal chaotic systems with topologically equivalent structures. The synchronization of multi-spatiotemporal chaotic syste... A backstepping approach is proposed for the synchronization of chain networks of multi-spatiotemporal chaotic systems with topologically equivalent structures. The synchronization of multi-spatiotemporal chaotic systems is imple- merited by adding the control only to a terminal node, and the controller is designed via a corresponding update law. The control law is applied to spatiotemporal Gray-Scott systems. Numerical results demonstrate the effectiveness and the feasibility of the proposed approach. 展开更多
关键词 spatiotemporal chaos backstepping design Lyapunov function chain complex networks
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大型油浸式变压器火灾风险集成评估方法
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作者 赵欣洋 王立志 +1 位作者 成诚 景伟 《消防科学与技术》 北大核心 2026年第1期56-63,共8页
大型油浸式变压器火灾易造成严重的后果损失,为此,提出一种动态火灾风险评估方法,为事故预防与风险管理提供指导。基于事故案例与行业统计数据分析油浸式变压器火灾成因,构建涵盖变压器本体部件固有风险、动态运行风险、附属设施失效风... 大型油浸式变压器火灾易造成严重的后果损失,为此,提出一种动态火灾风险评估方法,为事故预防与风险管理提供指导。基于事故案例与行业统计数据分析油浸式变压器火灾成因,构建涵盖变压器本体部件固有风险、动态运行风险、附属设施失效风险、外部环境触发因素、消防设备系统可靠性、消防安全管理水平6个维度的变压器火灾风险指标体系,提出涵盖4个严重程度等级的单指标分级评价方法;采用复杂网络方法构建火灾链式演化模型,基于节点重要性测度结果计算指标权重;基于TOPSIS法提出变压器总体火灾风险值与极端火灾风险值计算方法,通过实例应用展示评估模型应用过程。结果表明,油温上升、短路、电弧放电是重要度最高的变压器火灾风险点,所提出的变压器火灾风险评估方法能够在给出总体风险等级基础上,进一步细化呈现各维度风险状况。研究结果可为变压器火灾风险动态监测、风险降低措施的实施决策提供指导。 展开更多
关键词 变压器火灾 链式演化 复杂网络 风险评估 逼近理想解排序法
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