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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 of Branched Polyethylene via Bulky α-Diimine Nickel(II)-Catalyzed Ethylene Chain-Walking Polymerization
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作者 Zhengquan Dong Pei Li +1 位作者 Guoyong Xu Fuzhou Wang 《Open Journal of Organic Polymer Materials》 2024年第1期1-12,共12页
The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, ... The catalysis of olefin polymerization through the chain-walking process is a subject of great interest. In this contribution, the successful synthesis of a Brookhart-type unsymmetrical α-diimine nickel catalyst Ni, which contains both dibenzhydryl and phenyl groups, was determined by X-ray crystallography. The compound has a pseudo-tetrahedral geometry at the Ni center, showing pseudo-C2-symmetry. Upon activation with modified methylaluminoxane (MMAO), Ni1 exhibits high catalytic activity up to 1.02 × 107 g PE (mol Ni h)−1 toward ethylene polymerization, enabling the synthesis of high molecular weight branched polyethylene. The molecular weights and branching densities could be tuned over a very wide range. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature. The branching densities were decreased with increasing the polymerization temperature. 展开更多
关键词 Ethylene Polymerization α-Diimine Ni(II) complex chain-Walking Polymerization Branched Polyethylene
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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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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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群聚传播的凝结空间生产与价值指向 被引量:2
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作者 隋岩 揭其涛 《南昌大学学报(人文社会科学版)》 CSSCI 北大核心 2024年第2期130-140,共11页
互联网群聚传播生成的凝结空间强化了群聚传播多重关系缠绕的复杂机制。受到多元主体不平衡交往碰撞的影响,散漫、飘荡和漫渍的凝结空间随着互联网群聚传播的随机涨落处于永恒的流动之中,进而生产了复杂的关系链条。在以往的传播学视域... 互联网群聚传播生成的凝结空间强化了群聚传播多重关系缠绕的复杂机制。受到多元主体不平衡交往碰撞的影响,散漫、飘荡和漫渍的凝结空间随着互联网群聚传播的随机涨落处于永恒的流动之中,进而生产了复杂的关系链条。在以往的传播学视域中,空间始终是“缺席”或“被征服”的对象,西方空间学者虽然提出了空间生产理论,但是忽视了空间生产后伴随环境和交互作用而发生的跃变。随时随地“因事”而“凝结的空间”改变了以往空间的永恒性,借助群聚传播的时间之流对空间碎片的拼接与镶嵌,随时会发生位置漂移,没有边际亦无永久性的节点,只有永恒的空间聚合与消散,以及伴随这一过程的持续流动。凝结空间的流动习惯以多样性、复杂性、异质性来摧毁整体性和均质性。这种流动本身所具有的物质力量暗含了偶然性聚集的合力和对立性的张力,进而形成了斑斓杂陈的社会景观。在凝结空间的无限嵌套、互渗和叠置中,群聚传播的驳杂性增强了时空结构的混沌度。这些都提醒我们要重塑凝结空间中的交往理性,认识凝结空间生产的初始条件和演进规律,破除群聚传播空间生产的阻碍,实现自我超越,回归人类共通的价值本性。 展开更多
关键词 凝结空间 流动性 复杂关系链 互联网群聚传播
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B2B2C供应链物流-订单流复合网络鲁棒性研究
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作者 孙军艳 陈马骏驰 郭柳艺 《西安理工大学学报》 CAS 北大核心 2024年第2期269-277,共9页
基于渗流理论,考虑节点的渗流容量和受上下游失效节点的影响不同,设计了复合网络上下游级联失效策略,采用平均最短路径长度、最大连通子图率和网络全局效率评估B2B2C复合网络的鲁棒性。仿真表明:随着渗流容量系数的增加,网络鲁棒性增强... 基于渗流理论,考虑节点的渗流容量和受上下游失效节点的影响不同,设计了复合网络上下游级联失效策略,采用平均最短路径长度、最大连通子图率和网络全局效率评估B2B2C复合网络的鲁棒性。仿真表明:随着渗流容量系数的增加,网络鲁棒性增强;复合网络对于蓄意攻击的抵抗性较差,平均最短路径长度、全局效率和最大连通子图率呈断崖式下降到0,网络基本瘫痪,而面对随机攻击则具有较好的鲁棒性;与物流网络相比,复合网络平均度低40.6%,幂指数高12.1%,鲁棒性较好。 展开更多
关键词 供应链 复杂网络 渗流理论 级联失效 鲁棒性
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复杂产品人工智能生产调度研究
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作者 余阿东 《机械设计与制造》 北大核心 2024年第7期26-30,共5页
针对复杂产品生产调度协同性不足问题,提出一种基于关键链的多产品人工智能生产调度模式。结合复杂产品时序约束特点,以最小产品拖期和在制品库存为优化目标,搭建了基于关键链的多产品项目人工智能生产调度优化模型,基于遗传算法与模拟... 针对复杂产品生产调度协同性不足问题,提出一种基于关键链的多产品人工智能生产调度模式。结合复杂产品时序约束特点,以最小产品拖期和在制品库存为优化目标,搭建了基于关键链的多产品项目人工智能生产调度优化模型,基于遗传算法与模拟退火算法,设计了遗传退火算法(GA-SA)对多产品项目人工智能生产调度优化模型求解,并以某重型机械企业生产的矿渣立磨为例验证了优化模型和智能算法的有效性,实现了复杂产品生产调度精益性和智能性目标,研究结果表明:采用GA-SA+关键链调度方法,产品可以做到准时交付且在制品库存减少24%。 展开更多
关键词 关键链 复杂产品 生产调度 遗传退火算法 人工智能
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