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Three-dimensionally interconnected Co9S8/MWCNTs composite cathode host for lithium–sulfur batteries 被引量:3
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作者 Shengyu Zhao Xiaohui Tian +2 位作者 Yingke Zhou Ben Ma Angulakshmi Natarajan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第7期22-29,I0002,共9页
Several challenging issues,such as the poor conductivity of sulfur,shuttle effects,large volume change of cathode,and the dendritic lithium in anode,have led to the low utilization of sulfur and hampered the commercia... Several challenging issues,such as the poor conductivity of sulfur,shuttle effects,large volume change of cathode,and the dendritic lithium in anode,have led to the low utilization of sulfur and hampered the commercialization of lithium–sulfur batteries.In this study,a novel three-dimensionally interconnected network structure comprising Co9 S8 and multiwalled carbon nanotubes(MWCNTs)was synthesized by a solvothermal route and used as the sulfur host.The assembled batteries delivered a specific capacity of1154 m Ah g-1 at 0.1 C,and the retention was 64%after 400 cycles at 0.5 C.The polar and catalytic Co9 S8 nanoparticles have a strong adsorbent effect for polysulfide,which can effectively reduce the shuttling effect.Meanwhile,the three-dimensionally interconnected CNT networks improve the overall conductivity and increase the contact with the electrolyte,thus enhancing the transport of electrons and Li ions.Polysulfide adsorption is greatly increased with the synergistic effect of polar Co9 S8 and MWCNTs in the three-dimensionally interconnected composites,which contributes to their promising performance for the lithium–sulfur batteries. 展开更多
关键词 three-dimensional network structure MWCNTS Polar and catalytic Co9S8 Lithium–sulfur batteries
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Synthesis and Crystal Structure of a Three-dimensional (3D) Complex Mn(H_2O)_2(HNic)_2 (HNic=2-Hydroxynicotinic Acid)
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作者 LI Yu-Mei CHE Yun-Xia ZHENG Ji-Min 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第5期572-576,共5页
The title complex Mn(H2O)2(HNic)2 (C22H12MnN2O8, Mr = 367.18) crystallizes in monoclinic, space group P21/c with a = 7.5735(8), b = 12.5295(13), c = 7.6466(8)A.β = 101.2790(10)°, Z = 2, V= 711.59... The title complex Mn(H2O)2(HNic)2 (C22H12MnN2O8, Mr = 367.18) crystallizes in monoclinic, space group P21/c with a = 7.5735(8), b = 12.5295(13), c = 7.6466(8)A.β = 101.2790(10)°, Z = 2, V= 711.59(13) A^3, D, = 1.714 g/cm^3,μ(MoKa) = 0.974 mm^-1, F(000) = 374, R1 (1255 observed reflections (Ⅰ 〉 2σ(Ⅰ)) = 0.0250) and wR2 = 0.0662 (all data). In this paper, we report the complexation of Mn(Ⅱ) by the bidentate ligand 2-hydroxynicotinic acid (HNic). In the crystal the Mn(Ⅱ) ion exhibits a deformed octahedron structure. The title complex Mn(H2O)2(HNic)2 has a three-dimensional (3D) network structure extended by hydrogen bonds, which are formed by two typical eight-membered hydrogen-bonded rings. 展开更多
关键词 COMPLEX crystal structure three-dimensional network
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Three-dimensional-printed polycaprolactone scaffolds with interconnected hollow-pipe structures for enhanced bone regeneration 被引量:2
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作者 Jiahua Duan Dong Lei +6 位作者 Chen Ling Yufeng Wang Zhicheng Cao Ming Zhang Huikang Zhang Zhengwei You Qingqiang Yao 《Regenerative Biomaterials》 SCIE EI 2022年第1期471-479,共9页
Three-dimensional(3D)-printed scaffolds are widely used in tissue engineering to help regenerate critical-sized bone defects.However,conventional scaffolds possess relatively simple porous structures that limit the de... Three-dimensional(3D)-printed scaffolds are widely used in tissue engineering to help regenerate critical-sized bone defects.However,conventional scaffolds possess relatively simple porous structures that limit the delivery of oxygen and nutrients to cells,leading to insufficient bone regeneration.Accordingly,in the present study,perfusable and permeable polycaprolactone scaffolds with highly interconnected hollow-pipe structures that mimic natural micro-vascular networks are prepared by an indirect onepot 3D-printing method.In vitro experiments demonstrate that hollow-pipe-structured(HPS)scaffolds promote cell attachment,proliferation,osteogenesis and angiogenesis compared to the normal non-hollow-pipe-structured scaffolds.Furthermore,in vivo studies reveal that HPS scaffolds enhance bone regeneration and vascularization in rabbit bone defects,as observed at 8 and 12weeks,respectively.Thus,the fabricated HPS scaffolds are promising candidates for the repair of critical-sized bone defects. 展开更多
关键词 three-dimensional printing interconnected hollow-pipe structure bone regeneration VASCULARIZATION POLYCAPROLACTONE
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Generative deep-learning-embedded asynchronous structured light for three-dimensional imaging 被引量:1
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作者 Lei Lu Chenhao Bu +4 位作者 Zhilong Su Banglei Guan Qifeng Yu Wei Pan Qinghui Zhang 《Advanced Photonics》 SCIE EI CAS CSCD 2024年第4期45-58,共14页
Three-dimensional(3D)imaging with structured light is crucial in diverse scenarios,ranging from intelligent manufacturing and medicine to entertainment.However,current structured light methods rely on projector-camera... Three-dimensional(3D)imaging with structured light is crucial in diverse scenarios,ranging from intelligent manufacturing and medicine to entertainment.However,current structured light methods rely on projector-camera synchronization,limiting the use of affordable imaging devices and their consumer applications.In this work,we introduce an asynchronous structured light imaging approach based on generative deep neural networks to relax the synchronization constraint,accomplishing the challenges of fringe pattern aliasing,without relying on any a priori constraint of the projection system.To overcome this need,we propose a generative deep neural network with U-Net-like encoder-decoder architecture to learn the underlying fringe features directly by exploring the intrinsic prior principles in the fringe pattern aliasing.We train within an adversarial learning framework and supervise the network training via a statisticsinformed loss function.We demonstrate that by evaluating the performance on fields of intensity,phase,and 3D reconstruction.It is shown that the trained network can separate aliased fringe patterns for producing comparable results with the synchronous one:the absolute error is no greater than 8μm,and the standard deviation does not exceed 3μm.Evaluation results on multiple objects and pattern types show it could be generalized for any asynchronous structured light scene. 展开更多
关键词 structured light fringe pattern projection ASYNCHRONY deep learning generative neural networks three-dimensional imaging
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Preparation and Crystal Structure of Sarcosine 5-Nitrosalicylic Acid Organic Adduct
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作者 金轶 车云霞 +1 位作者 魏荣敏 郑吉民 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第11期1292-1294,共3页
The title compound (C10H12N2O7, Mr = 272.22) crystallizes in triclinic, space group P1 with a = 5.532(2), b = 9.760(4), c = 11.731(5) ?, α = 68.107(7), β = 89.179(7), γ = 77.830(7)o, V = 573.1(4) ?3, Z = 2, Dc = 1.... The title compound (C10H12N2O7, Mr = 272.22) crystallizes in triclinic, space group P1 with a = 5.532(2), b = 9.760(4), c = 11.731(5) ?, α = 68.107(7), β = 89.179(7), γ = 77.830(7)o, V = 573.1(4) ?3, Z = 2, Dc = 1.578 g/cm3, F(000) = 284 and μ(MoKa) = 0.136 mm-1. The final R = 0.0400 and wR = 0.0951 for 1468 observed reflections with I > 2σ(I). The title compound is a 1:1 adduct of sarcosine and 5-nitrosalicylic acid. The nitrogen atom of sarcosine is protonated, and the proton is from the carboxyl group of sarcosine and 5-nitrosalicylic acid with the probability of 50 percent for each. The 5-nitrosalicylic acid and sarcosine molecule of the title adduct are ABAB arranged along the c axis. There exist a lot of hydrogen bonds in the structure, linking sarcosine and 5-nitrosalicylic acid to form a three-dimensional network. 展开更多
关键词 crystal structure SARCOSINE 5-nitrosalicylic acid hydrogen bond PROTONATED three-dimensional network
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Hydrothermal Synthesis and Crystal Structure of a New Sandwich-type Molybdenum Phosphate
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作者 杨文斌 卢灿忠 +1 位作者 吴传德 庄鸿辉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第2期137-142,共6页
The crystal structure of the title compound, [enH2][Fe{MoⅤ6O12(OH)3(HPO4)- (H2PO4)3}2]6en6H2O (en = H2NCH2CH2NH2), hydrothermally synthesized from a mixture of Na2MoO42H2O, Fe2(SO4)3, H3PO4, H2N(CH2)2NH2 and water, h... The crystal structure of the title compound, [enH2][Fe{MoⅤ6O12(OH)3(HPO4)- (H2PO4)3}2]6en6H2O (en = H2NCH2CH2NH2), hydrothermally synthesized from a mixture of Na2MoO42H2O, Fe2(SO4)3, H3PO4, H2N(CH2)2NH2 and water, has been determined by single- crystal X-ray diffraction. The crystal is of triclinic, space group P?with a = 11.9014(1), b = 13.4246(2), c = 13.8719(2) , a = 87.465(1), b = 69.981(1), g = 64.960(1)? V = 1873.46(4) 3, Z = 1, Mr = 2997.89, F(000) = 1466, m = 2.427 mm-1 and Dc = 2.657 g/cm3. The final R = 0.0404 for 5570 observed reflections (I > 2s(I)). The structural analysis reveals that each cluster anion contains two coplanar {Mo6} rings of six edge-sharing Mo(O5OH) octahedra, and the two {Mo6} rings are linked together through one octahedral FeⅡ ion to generate a sandwich-type cluster with rigorous () symmetry. Moreover, these clusters are further linked into a three-dimensional frame- work by hydrogen bonds. 展开更多
关键词 sandwich-type molybdenum (Ⅴ) phosphate hydrothermal synthesis hydrogen bond three-dimensional network crystal structure
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Synthesis and Crystal Structure of O-Ethyl-N- (2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-thiocarbamate
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作者 YANGBo ZHANGShu-sheng +2 位作者 WANGYan-fang LIXue-mei JIAOKui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第2期163-165,共3页
The crystal and molecular structures of O-ethyl-N-(2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-thiocarbamate were determined by X-ray crystallography. It crystallizes in the orthorhombic system with space group P2(1)2(1)2(... The crystal and molecular structures of O-ethyl-N-(2,3,4-tri-O-acetyl-β-D-xylopyranosyl)-thiocarbamate were determined by X-ray crystallography. It crystallizes in the orthorhombic system with space group P2(1)2(1)2(1), lattice parameters a=0.90636(18) nm, b=0.94716(19) nm, c=2.1855(4) nm, V=1.8762(7) nm 3, and Z=4. All the substituents are in equatorial positions. There are four intramolecular interactions, each forming a five-membered ring. The molecules are linked by interactions to form three-dimensional framework. Atoms O6 and O8 show positional disorder. 展开更多
关键词 O-Ethyl-N-(2 3 4-tri-O-acetyl-β-D-xylopyranosyl)-thiocarbamate Crystal structure three-dimensional network
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K频段新型相控阵双波束接收组件研究
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作者 高钟澜 王鹏毅 王新 《计算机测量与控制》 2025年第4期200-208,共9页
基于射频多层混压板设计了一款K频段新型相控阵双波束接收组件,在三维结构下通过电容加载技术创新优化设计一分六十四Wilkinson功率合路网络,在具备良好性能指标情况下,相比传统合路网络布阵尺寸更小,在此基础上利用延时补偿技术精准控... 基于射频多层混压板设计了一款K频段新型相控阵双波束接收组件,在三维结构下通过电容加载技术创新优化设计一分六十四Wilkinson功率合路网络,在具备良好性能指标情况下,相比传统合路网络布阵尺寸更小,在此基础上利用延时补偿技术精准控制组件通道间相位一致性,并在器件密集布局位置设置隔离金属柱排除腔体谐振干扰,实现了组件的高频化、高密度可靠性设计,能够很好地适应高频段下机载工作环境应用需要;在19.6~21.2 GHz设计频段内,一分六十四功率合成网络的输入端口回波损耗值大于18 dB,输出端口和输入端口间插入损耗值小于19.8 dB,具有良好的隔离度和相位一致性;对相控阵组件中的垂直互联结构进行了仿真分析,对传输不连续性结构处进行结构优化,实现了低损耗传输;经测试,在19.6~21.2 GHz频段内,双波束接收组件的驻波比小于1.5,组件单通道增益值大于22 dB,不同通道间相位差小于20°。 展开更多
关键词 合路网络 双波束 电容加载技术 功率分配器 互联结构 低损耗传输
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折叠局部扭曲立方体的结构连通度
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作者 魏宝军 把丽娜 《南开大学学报(自然科学版)》 北大核心 2025年第2期115-120,共6页
图G的T-子结构连通度κs(G;T)是指G的一个同构于T的子图的子图集F的最小基数,使得G-F是不连通的或单点.n维折叠局部扭立方体记为FLTQn.研究了网络FLTQn的路结构连通度和路子结构连通度.对于κ-点路Pκ,当3≤k≤2n时,对于奇数k和偶数k,结... 图G的T-子结构连通度κs(G;T)是指G的一个同构于T的子图的子图集F的最小基数,使得G-F是不连通的或单点.n维折叠局部扭立方体记为FLTQn.研究了网络FLTQn的路结构连通度和路子结构连通度.对于κ-点路Pκ,当3≤k≤2n时,对于奇数k和偶数k,结构(子结构)连通度分别为[2(n+1)/k+1]和[2(n+1)/k]. 展开更多
关键词 互联网络 结构连通度 路径
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基于标准空间光传送网协议的天地一体化网络构建研究
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作者 邓伟 李允博 +1 位作者 张剑寅 刘亮 《电信科学》 北大核心 2025年第7期85-95,共11页
伴随航天、航空及地面通信技术的迅猛发展,构建具备全球无缝覆盖、随遇接入与按需服务特性的空天地一体化网络,已成为通信网络发展的必然趋势。基于标准空间光传送网协议实现天地一体化网络展开研究:首先,提出空间光传送网是构建天地一... 伴随航天、航空及地面通信技术的迅猛发展,构建具备全球无缝覆盖、随遇接入与按需服务特性的空天地一体化网络,已成为通信网络发展的必然趋势。基于标准空间光传送网协议实现天地一体化网络展开研究:首先,提出空间光传送网是构建天地一体化网络的核心基石,阐述空间光通信的标准现状,剖析制式差异致使卫星信息互通受限的困境;其次,从协议层面深入探究空间光传送网的组网功能,根据卫星高速运动、星间链路切换频繁、星载资源有限等特性,提出适配空间信息网络环境的新型帧结构与可靠传输协议,支撑多星座互联互通,在确保数据精准、可靠传输的同时,提升网络资源利用效率;最后,总结此网络架构于行业应用的前景,提出未来应着重开展统一空间光传送网技术标准化的布局研究,为天地一体化网络的高效运转与广泛应用筑牢根基。 展开更多
关键词 空间光传送网 帧结构 6G 天地一体化网络 互联互通
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The three-dimensional structure and the relationship between external and internal vascularizations in the brain of rat embryos 被引量:1
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作者 张亮 赵阳 周家文 《Chinese Medical Journal》 SCIE CAS CSCD 2004年第2期280-285,共6页
Background There have been no detailed reports of the three-dimensional structure and the relationship between the external and internal vascularizations observed successively for a long duration in the rat fetus, alt... Background There have been no detailed reports of the three-dimensional structure and the relationship between the external and internal vascularizations observed successively for a long duration in the rat fetus, although many authors have studied the vascular morphology of the developing brain. This study examined the three-dimensional structure of both the external and internal vascularizations of the prenatal rat telencephalon from embryonic days 12 (E12) to 20 (E20).Method A microvascular casting method for scanning electron microscopy (SEM) was used in this study, along with vascular staining using gold-gelatine solution-autometallography (GGS-AMG) after intravascular injection of colloidal gold, as well as hematoxylin-eosin ( HE) staining for paraffin embedded specimens.Results In GGS-AMG stains, E16 fetuses had a few short perforating cortical blood vessels (SPCVs); E17 fetuses had long perforating cortico-medullary vessels (LPCVs). Older fetuses had specific patterns of vascular networks in the cortex and the deeper subcortical part of the telencephalon. In the cortex, fine longitudinal blood vessels were connected by transverse channels. The deep telencephalon had fine blood vessels running in all directions. Using SEM, the external vascularization was already visible in E12 fetuses as arborizations of arterial branches, forming a mesh of fine vascular networks covering the telencephalon. A coralliform fine venous plexus was observed in the external vascularization of E16 fetuses. There were ring-like anastomoses and bud-like protrusions in the network of small blood vessels, most likely the angiogenesis of fetal vessels. From E12 to E16, an immature and incomplete internal vascularization began to appear. There were short blood vessels with ballooned terminals branching from the external vascularization. They penetrated the brain tissue to form networks in the superficial layer, comparable to SPCVs. In E17 to E20 fetuses, tortuous venous branches, straight arterial blood vessels, and a fine network of small blood vessels formed the external vascularization. There were fewer arterial than venous branches connecting to the fine networks of small blood vessels. LPCVs were noted at E17, at the time the white matter emerged. They branched from the external vascularization, and perpendicularly penetrated the brain surface, traversing the cortical plate, and entering into the deep brain. At E17, arterial and venous blood vessels could be clearly distinguished in the external vascularization. At E20, the cortex and white matter contained specific arrangements of networks of fine blood vessels, as seen by GGS-AMG staining.Conclusion These findings show that the development of both the external and internalvascularization follows the development of thetelencephalon. In particular, the emergence ofthe cortical plate and white matter on E16 andE17 influence the development of both theinternal and the external vascularization. Thelaminal arrangement of blood vessels was notobserved corresponding to the respective laminalneuronal layers. 展开更多
关键词 cerebrovascular network rat telencephalon three-dimensional structure corrosion cast scanning electron microscopy
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高导热PVDF/Ag纤维膜的构建及其导热性能 被引量:2
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作者 齐庆欢 师晓含 +2 位作者 张庆 苑保奎 周玉嫚 《现代纺织技术》 北大核心 2024年第5期23-31,共9页
为了提高纤维材料的导热性能,选择不同尺寸的Ag片作为导热填料,通过静电纺丝技术一步构建了具有三维互通导热网络的PVDF/Ag纤维膜,对其形貌和化学结构进行表征,研究Ag片尺寸、Ag片含量、压缩程度对其导热性能的影响,并对其实际应用能力... 为了提高纤维材料的导热性能,选择不同尺寸的Ag片作为导热填料,通过静电纺丝技术一步构建了具有三维互通导热网络的PVDF/Ag纤维膜,对其形貌和化学结构进行表征,研究Ag片尺寸、Ag片含量、压缩程度对其导热性能的影响,并对其实际应用能力进行评估。结果表明:加入混合尺寸Ag片,能够形成单根纤维内部连通和纤维之间外部连通的三维互通网络结构。具有该结构的PVDF/Ag纤维膜表现出优异的导热性能,导热系数达0.1038 W/(m·K),比纯PVDF纤维膜提高了61%;将其压缩处理后,导热系数进一步提升至8.693 W/(m·K),是压缩前的83.6倍。此外,三维互通网络的PVDF/Ag纤维膜还展示出优异的力学应用能力和疏水性能。研究结果对进一步开发多功能集合的纺织品及柔性材料具有重要的参考价值。 展开更多
关键词 静电纺丝 PVDF Ag片 混合尺度 三维互通网络结构 纤维膜 导热性能
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考虑故障恢复的产业互联“智造”供需网级联失效模型
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作者 邓子玥 何建佳 《计算机系统应用》 2024年第7期222-229,共8页
大规模、数字化的产业互联“智造”供需网相比于传统供应链具有更强的响应调节能力和风险预防与恢复能力,但可能面临的风险种类更多且风险传播路径更广,导致其鲁棒性更易受到威胁,准确描述网络中故障风险的动态传播过程是提高其鲁棒性... 大规模、数字化的产业互联“智造”供需网相比于传统供应链具有更强的响应调节能力和风险预防与恢复能力,但可能面临的风险种类更多且风险传播路径更广,导致其鲁棒性更易受到威胁,准确描述网络中故障风险的动态传播过程是提高其鲁棒性的基础.首先,构建具有多个产业社团的产业互联“智造”供需网模型;其次,结合业务节点间相对关联度,构建具有相对故障概率的风险传播模型,再根据节点重要程度,建立同时考虑恢复概率和恢复周期的故障恢复模型;最后,基于改进引力模型构建网络,以网络相对连通率R作为指标,对不同故障和恢复场景下的级联失效进行仿真分析.仿真结果表明:在4组不同故障和恢复场景下均存在临界值导致R值长期处于不稳定状态;参数η和μ对R值的影响均具有一定的边际效应;当网络故障传播能力一定时,恢复能力越弱则R值振荡越明显,网络受影响规模越大,而当恢复能力一定时,故障强度越强R值振荡越明显,网络受影响规模越大. 展开更多
关键词 产业互联 供需网 多业务协同 社团结构 级联失效
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高速信号处理系统的体系结构研究 被引量:6
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作者 严胜刚 沈翠羽 +1 位作者 李林山 李志舜 《西北工业大学学报》 EI CAS CSCD 北大核心 1996年第4期554-557,共4页
依据信号处理任务的特点,结合流水线处理和并行处理,采用模块化设计方法,设计实现了一个由1个8086微处理器和13个高速数字信号处理器TMS320C25构成的多处理器系统。该系统采用双端口SRAM、FIFO进行互连网络... 依据信号处理任务的特点,结合流水线处理和并行处理,采用模块化设计方法,设计实现了一个由1个8086微处理器和13个高速数字信号处理器TMS320C25构成的多处理器系统。该系统采用双端口SRAM、FIFO进行互连网络的设计,系统的峰值运算能力为每秒2.6亿次以上的整数操作。该系统能够实时实现信号的空间处理和时间处理等,并作为小型声纳系统的信号处理机已经得到应用,并取得良好的结果。 展开更多
关键词 并行处理 流水线处理 系统结构 信号处理
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跨大区互联电网与省级电网大扰动振荡耦合机制 被引量:23
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作者 郑超 马世英 +7 位作者 盛灿辉 罗立波 林俊杰 刘道伟 秦晓辉 薛劲莹 张志强 陈得治 《中国电机工程学报》 EI CSCD 北大核心 2014年第10期1556-1565,共10页
华北电网与华中电网特高压交流互联后,位于华中电网西部末端且与互联通道电气距离最远的四川电网,其网内枢纽电站及其出线故障将会引发特高压通道功率大幅涌动,并成为约束南北电力互济的重要因素之一。首先分析了华北—华中特高压互联... 华北电网与华中电网特高压交流互联后,位于华中电网西部末端且与互联通道电气距离最远的四川电网,其网内枢纽电站及其出线故障将会引发特高压通道功率大幅涌动,并成为约束南北电力互济的重要因素之一。首先分析了华北—华中特高压互联电网网架拓扑结构与转动惯量分布特征;基于所定义的广义驱动能量,揭示华中不同省级电网故障扰动后,特高压通道华中侧落点电网的注入能量差异;通过理想主导振荡模态及大电网仿真轨迹分析,指出过渡期电网固有结构所决定的振荡机群同调性和振荡耦合叠加性,是导致四川网内故障激发大区振荡首摆驱动能量和反摆制动能量显著增大,进而引发特高压通道功率大幅涌动的根本原因。基于广义驱动能量的影响因素分析,提出相应的缓解措施。该研究可提升特高压大电网动态行为机制的认知能力和大电网安全稳定运行的驾驭能力。 展开更多
关键词 特高压交流 互联电网 功率涌动 网架结构 转动惯量 广义驱动能量 振荡耦合 缓解措施
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平原河网区水系结构连通性评价 被引量:37
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作者 茹彪 陈星 +2 位作者 张其成 王卫平 许钦 《水电能源科学》 北大核心 2013年第5期9-12,共4页
河湖水系连通在增强抵御水旱灾害能力、提高水资源统筹配置能力和改善河湖健康状况等方面均具有重要作用,已成为国家江河治理的重大课题,但相关的理论和技术研究尚处于探索阶段。基于水系结构连通性评价的内涵,探讨了水系连通性与水系... 河湖水系连通在增强抵御水旱灾害能力、提高水资源统筹配置能力和改善河湖健康状况等方面均具有重要作用,已成为国家江河治理的重大课题,但相关的理论和技术研究尚处于探索阶段。基于水系结构连通性评价的内涵,探讨了水系连通性与水系结构连通性的关系及水系结构连通性的影响要素,在分析了传统网络连通性评价方法在水网中的适用性基础上,提出了基于河道自然、社会双重属性的水系结构连通性评价方法,并通过对吴江市骨干水系结构连通性进行计算,验证了该方法的可行性。 展开更多
关键词 平原河网区 水系连通 结构连通性 自然属性 社会属性
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中压配电网柔性互联设备的电路拓扑与控制技术综述 被引量:36
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作者 张国驹 裴玮 +3 位作者 杨鹏 邓卫 朱恩泽 李倩 《电力系统自动化》 EI CSCD 北大核心 2023年第6期18-29,共12页
柔性互联技术可以实现配电网潮流灵活控制,是新型配电网实现坚强架构的重要技术手段。对中压配电网柔性互联设备的电路拓扑与控制技术进行了综述。首先,分析了可应用于中压配电网柔性互联设备的系统结构,包括应用场景与设备组成部分。然... 柔性互联技术可以实现配电网潮流灵活控制,是新型配电网实现坚强架构的重要技术手段。对中压配电网柔性互联设备的电路拓扑与控制技术进行了综述。首先,分析了可应用于中压配电网柔性互联设备的系统结构,包括应用场景与设备组成部分。然后,对中压配电网柔性互联的电路拓扑进行了对比分析,包括模块化多电平高压型和变压器降压型两类,并对技术发展进行了展望。最后,对中压配电网柔性互联设备的跟网型和构网型控制技术进行了综述,指出了虚拟同步发电机控制策略应用于柔性互联设备时所需面对的挑战。 展开更多
关键词 配电网 柔性互联设备 设备系统结构 电路拓扑 控制策略
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基于序分量法的V/V接线牵引变压器实用快速短路计算方法 被引量:9
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作者 吴奎忠 王建勋 +1 位作者 马丽红 吴奎华 《电力系统保护与控制》 EI CSCD 北大核心 2012年第2期61-65,共5页
三相V/V接线变压器在电铁牵引系统中得到广泛应用,然而V/V接线变压器结构相对于三相系统具有严重的不对称性,这给现有的以对称序分量为基础的电力系统整定计算带来困难。通过对V/V接线变压器的接线方式及其等效模型进行深入分析,提出了... 三相V/V接线变压器在电铁牵引系统中得到广泛应用,然而V/V接线变压器结构相对于三相系统具有严重的不对称性,这给现有的以对称序分量为基础的电力系统整定计算带来困难。通过对V/V接线变压器的接线方式及其等效模型进行深入分析,提出了基于序分量法的实用故障计算方法,给出了各种故障类型的序分量图及计算公式。并与基于分相法的故障计算方法进行比较研究,结合算例验证了此方法的有效性。将其与现行输电网故障计算程序相结合,对现有故障计算程序的复杂故障计算模块略作调整,即可对V/V接线变压器故障进行快速计算,从而形成了一种广泛实用的计算方法。 展开更多
关键词 V/V接线变压器 短路计算 序分量 电气化铁路 复合序网图
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Internet拓扑结构的静态概率模型研究 被引量:5
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作者 王林 戴冠中 《西北工业大学学报》 EI CAS CSCD 北大核心 2005年第3期341-346,共6页
近年来,许多学者对Internet的拓扑结构进行了研究,发现了幂律(PowerLaw)规律,然而这些研究基本上针对的是Internet拓扑的局部性质。该文从Internet拓扑的一个参数(度秩指数)出发,定义了Internet拓扑结构的一个静态概率模型。利用静态概... 近年来,许多学者对Internet的拓扑结构进行了研究,发现了幂律(PowerLaw)规律,然而这些研究基本上针对的是Internet拓扑的局部性质。该文从Internet拓扑的一个参数(度秩指数)出发,定义了Internet拓扑结构的一个静态概率模型。利用静态概率模型,对文中所提出的Internet拓扑中具有整体意义的两个重要性质(连接率和吸引率)进行了深入研究。通过理论研究和仿真研究,获得了下列成果:①发现了Internet中的一个新的幂律(即连接率满足幂律),并且相关系数超过99.3%。②发现了Internet中吸引率与Internet中幂律之间具有的内在联系;③发现了Internet中的度秩指数的临界值为1。④证明了在Internet中存在自治系统(AS)核心,而对AS核心而言,Internet可视为一个星形结构。 展开更多
关键词 Internet拓扑结构 自治系统(AS)核心 幂律 静态概率模型
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基于参数的层次化Mesh互连片上网络结构 被引量:2
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作者 简刚 韩国栋 +1 位作者 马钊坤 周玉瀚 《计算机应用研究》 CSCD 北大核心 2016年第6期1857-1861,共5页
提出一种基于参数的层次化Mesh互连片上网络结构——PHNo C,解决片上网络规模扩张引起的通信延迟和吞吐性能下降问题。采用分簇多层次互连的思想,提高片上网络扩展性和连通性;引入层数和分簇类型参数,实现不同网络规模的灵活配置;引入... 提出一种基于参数的层次化Mesh互连片上网络结构——PHNo C,解决片上网络规模扩张引起的通信延迟和吞吐性能下降问题。采用分簇多层次互连的思想,提高片上网络扩展性和连通性;引入层数和分簇类型参数,实现不同网络规模的灵活配置;引入跨层流控参数,控制并平衡层间负载流量。仿真实验表明,在多种流量模式下,不同网络规模时,PHNo C结构的延迟和吞吐性能相比传统的平面或两层结构优势明显,而资源开销和实现复杂度增加不大,说明增加多层互连资源可有效换取通信性能的提高。 展开更多
关键词 片上网络 参数化设计 分簇结构 层次化互连
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