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基于顶点组重分配的动态增量图划分算法

软件学报 2024年第4期35卷 1819-1840页

作者：李贺刘延娜杨舒琪黄健斌乔少杰西安电子科技大学计算机科学与技术学院陕西西安710126 成都信息工程大学软件工程学院四川成都610103

图划分是分布式图计算中的一项基础工作,其作用是将大规模图进行划分并分配到集群中的不同机器上.图划分的质量对分布式图计算的性能有很大的影响,其目标是降低负载平衡和最小化边割.如今,现实中的图数据通常呈动态增长态势,这就需要一... 详细信息

图划分是分布式图计算中的一项基础工作,其作用是将大规模图进行划分并分配到集群中的不同机器上.图划分的质量对分布式图计算的性能有很大的影响,其目标是降低负载平衡和最小化边割.如今,现实中的图数据通常呈动态增长态势,这就需要一种能够处理动态增量图的划分方法,在图数据动态增长的过程中确保划分的质量不受影响.目前虽然有一些动态图划分算法被提出,但它们不能同时专注于实时处理动态变化和获得高质量的划分结果.提出基于顶点组重分配的动态增量图划分算法(ED-IDGP)来解决大规模动态增量图的划分问题.在ED-IDGP算法中,设计实时处理4种不同单元更新类型的动态处理器,并在每次处理完单元更新后通过在分区发生动态变化的附近执行局部优化器进一步提高图划分的质量.在ED-IDGP的局部优化器中,利用基于改进标签传播算法的顶点组搜索策略搜索顶点组,并利用提出的顶点组移动增益公式衡量最有益的顶点组,将该顶点组移动到目标分区中做优化.在真实数据集上从不同的角度和度量指标评估了ED-IDGP算法的性能和效率.

关键词：图划分局部优化动态增量图划分算法

Chemical and spectroscopic characterization of humic substances from sediment and riparian soil of a highly polluted urban riv.r(Suquía Riv.r,Córdoba,Argentina)

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International Journal of Sediment Research 2020年第3期35卷 287-294页

作者： Carolina Merlo Carolina v.zquez ana Graciela Iriarte Carlos Matías Romero Instituto Multidisciplinario de Biologia v.getal (CONICET) Facultad de Ciencias Agropecuarias Universidad Nacional de Cordoba INFIQC Departament of FisicoquimicaFacultad de Ciencias QuimicasUniversidad Nacional de Cordoba Agriculture and Agri-Food Canada Lethbridge Research and Development Centre Department of Biological Sciences University of Lethbridge

The Suquia Riv.r,the largest urban riv.r in Cordoba(Argentina),has been sev.rely polluted for *** must be taken to restore its env.ronmental quality by managing riparian zones for increased water-self *** current study aimed to characterize organic matter(OM) dynamics and humic substances(HS) spectrochemical properties along the lower-middle basin of the Suquia *** soil(0-20 cm) and sediment(0-10 cm) samples were collected from a reference location(S1)and four polluted sites(S2-S5) during a low-flow *** contents of soil and sedimentary OM and HS fractions were analyzed by wet oxidation,as well as HS Fourier transform infrared(FT-IR) and ultrav.olet-v.sible(Uv.v.s) spectrochemical *** OM and HS fractions from riparian soil were high upstream of Cordoba City(S1 and S2,50.2-50.4 g/kg OM) and within a 50 km downstream location(S5,30.9 g/kg OM) owing to a surplus of fresh plant biomass-carbon(C) *** heterogeneous sediment samples did not show any significant differences among sites(P> 0.05).The lowest v.lues of the ratio of absorbances at 465 and 665 nm(E4/E6)(1.78) and the Δ log K(0.15) coefficient(a measure of HS maturity degree) were obtained downstream of Cordoba City,for both riparian soil and sediment,indicating that HS were enriched by more condensed aromatic structures within highly degraded portions of the *** samples exhibited similar IR spectra,implying ov.rlapping recalcitrant-C structures at the functional group lev.l,but with different absorbance *** from the current study constitute a baseline for understanding the chemical nature of HS from sediment and riparian soil along the Suquia Riv.r and can be used as a reference for future studies tracking OM compositional changes ov.r time.

关键词： Lotic ecosystems Organic matter Humic acids FT-IR spectroscopy Uv.v.s spectroscopy

Thermal effects and ev.lution of the defect concentration based on shear modulus relaxation data in a Zr-based metallic glass

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Chinese Physics B 2020年第8期29卷 133-136页

作者： Qi Hao Ji-Chao Qiao E v.Goncharov. G v.Afonin Min-na Liu Yi-Ting Cheng v.A Khonik School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710072China Department of General Physics Voronezh State Pedagogical UniversityLenin Street 86Voronezh 394043Russia

A relationship between thermal effects and relaxation of the high-frequency shear modulus upon heat treatment of bulk Zr48(Cu5/6Ag1/6)44Al8 metallic glass is *** relationship is attributed to the relaxation of a interstitial-type defect system frozen-in from the melt upon glass *** data show that thermal effects occurring on heating include heat release below the glass transition temperature,heat absorption abov. it and heat release caused by *** equation deriv.d within the Interstitialcy theory can be used to calculate the shear modulus relaxation using the calorimetric *** obtained results are used to trace the defect concentration as functions of temperature and thermal prehistory.

关键词： shear modulus metallic glass structural relaxation interstitialcy theory

Purification and Characterization of Jararassin-I, A Thrombin-like Enzyme from Bothrops jararaca Snake v.nom

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 798-802页

作者： Débora F. v.EIRA,Leandra WATanaBE,Carolina D. SANT′ana,Silv.0} MARCUSSI,Suely v. SAMPAIO,Andreimar M. SOARES,Raghuv.r K. ARNI Departamento de Física Instituto de Biociências Letras e Ciências Exatas Univ.rsidade Estadual Paulista UNESP 15054-000 Sāo José do Rio Preto SP Brazil Departamento de Física Instituto de Biociências Letras e Ciências Exatas Univ.rsidade Estadual Paulista UNESP 15054-000 Sāo José do Rio Preto SP Brazil Unidade de Biotecnologia Univ.rsidade de Ribeirāo Preto UnaERP Ribeirāo Preto SP Brazil Departamento de Análises Clínicas Toxicológicas e Bromatológicas FCFRP Univ.rsidade de S?o Paulo USP Ribeirāo Preto SP Brazil Unidade de Biotecnologia Univ.rsidade de Ribeirāo Preto UnaERP Ribeirāo Preto SP Brazil Departamento de Bioquímica e Imunologia FMRP Univ.rsidade de S?o Paulo USP Ribeirāo Preto SP Brazil Departamento de Análises Clínicas Toxicológicas e Bromatológicas FCFRP Univ.rsidade de Sāo Paulo USP Ribeirāo Preto SP Brazil Unidade de Biotecnologia Univ.rsidade de Ribeirāo Preto UnaERP Ribeirāo Preto SP Brazil Departamento de Física Instituto de Biociências Letras e Ciências Exatas Univ.rsidade Estadual Paulista UNESP 15054-000 Sāo José do Rio Preto SP Brazil

A thrombin-like serine protease, jararassin-I, was isolated from the v.nom of Bothrops jararaca. The protein was obtained in high yield and purity by a single chromatographic step using the affinity resin Benzamidine-Sepharose CL-6B. SDS-PAGE and dynamic light scattering analyses indicated that the molecular mass of the enzyme was about 30 kD. The enzyme possessed fibrinogenolytic and coagulant activ.ties. The jararassin-I degraded the Bβ chain of fibrinogen while theAα chain and γ chain were unchanged. Proteases inhibitors, PMSF and benzamidine inhibited the coagulant activ.ty. These results showed jararassin- I is a serine protease similar to coagulating thrombin-like snake v.nom proteases, but it specifically cleav.s Bβ chain of bov.ne fibrinogen. Single crystals of enzyme were obtained (0.2 mm×0.2 mm×0.2 mm) and used for X-ray diffraction experiments.

关键词： snake v.nom Bothrops jararaca serine protease thrombin-like fibrinogenolytic activ.ty crystallization

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基于单目深度估计变电站场景的语义分割模型

电力系统装备 2024年第5期 179-181页

作者：张娜王大伟国网山西省电力公司电力科学研究院山西太原030002

针对现有语义分割方法缺乏三维深度几何信息的有效学习,导致复杂变电站场景下对物体语义分割精度低的问题,文章提出了基于单目深度估计变电站场景的语义分割模型。该模型由DeepLab v.+辅图像语义分割模型与AdaBinsModule单目深度估计模... 详细信息

针对现有语义分割方法缺乏三维深度几何信息的有效学习,导致复杂变电站场景下对物体语义分割精度低的问题,文章提出了基于单目深度估计变电站场景的语义分割模型。该模型由DeepLab v.+辅图像语义分割模型与AdaBinsModule单目深度估计模型两部分组成。首先,AdaBinsModule根据可见光图像生成对应深度图,从而提取到图像中目标物体在三维空间中的深度信息。其次,采用矩阵相乘的方式将深度图中深度信息作为权重与可见光图像融合,并根据既定深度阈值弱化图像中远距离无效背景像素,以减少其在后续图像分割阶段对目标物体分割精度的影响。最后,将融合后的图像输入DeepLab v.+辅图像语义分割模型中进行语义分割。试验表明,相比基准模型,文章所提方法能更好地提取分割目标的深度轮廓特征,语义分割精度提升明显。

关键词：单目深度估计语义分割图像融合深度图变电站

ZL101/6061铝合金搅拌摩擦焊接头组织及性能研究

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兵器材料科学与工程 2024年第5期47卷 39-44页

作者：顾苏怡闵娜詹恒辉苏州市职业大学机电工程学院江苏苏州215104 上海大学分析测试中心上海200444 江苏科技大学材料科学与工程学院江苏镇江212003

采用搅拌摩擦焊接ZL101铸造铝合金和6061铝合金,转速为1000 r/min,研究不同焊接速度和压入量对铝合金接头组织和性能的影响。结果表明:当焊接速度为150 mm/min,压入量为6 mm时,铝合金接头的成型较美观;接头主要以α(Al)相为基体,在基体... 详细信息

采用搅拌摩擦焊接ZL101铸造铝合金和6061铝合金,转速为1000 r/min,研究不同焊接速度和压入量对铝合金接头组织和性能的影响。结果表明:当焊接速度为150 mm/min,压入量为6 mm时,铝合金接头的成型较美观;接头主要以α(Al)相为基体,在基体上分布着Al4Si第二相;铝合金接头的抗拉强度达到最大值,为92.53 MPa;焊接接头的硬度总体上呈“W”趋势,焊核区硬度高,热机械影响区的硬度略微下降,热影响区的硬度又有所回升。此工艺参数条件下铝合金接头的耐腐蚀性能最好,自腐蚀电位和自腐蚀电流密度分别为-0.6933 v.3.17×10^(-7) A/cm^(2)。

关键词： ZL101铸造铝合金 6061铝合金搅拌摩擦焊工艺参数显微组织性能

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Structure and dielectric properties of (1-x)na_(0.5)Bi_(0.5)TiO_(3-x)na_(0.5)K_(0.5)NbO_(3)

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Journal of Adv.nced Dielectrics 2024年第1期14卷 82-88页

作者： E.v.Glazunov. L.A.Shilkina A.S.Chekhov. A.v.nazarenko I.A.v.rbenko L.A.Reznichenko Research Institute of Physics Southern Federal University Rostov-on-Don344090Russia Faculty of Physics Southern Federal University Rostov-on-Don344090Russia Southern Scientific Center of the Russian Academy of Sciences Rostov.on-Don 344006Russia

The solid solutions of the(1-x)na_(0.5)Bi_(0.5)TiO_(3-x)na_(0.5)K_(0.5)NbO_(3) system were produced by the conv.ntional ceramic technology using mechanical activ.tion of the synthesized *** was found that in the(1-x)na_(0.5)Bi_(0.5)TiO_(3-x)na_(0.5)K_(0.5)NbO_(3) system at room temperature,a number of morphotropic phase transitions occur:rhombohedral!cubic!tetragonal!monoclinic *** introduction of a small amount of na_(0.5)K_(0.5)NbO_(3) leads to an increase in the temperature stability of the dielectric properties of ceramics.A change in the relaxor properties of the solid solutions of the(1-x)na_(0.5)Bi_(0.5)TiO_(3-x)na_(0.5)K_(0.5)NbO_(3) system was *** increase in energy density and energy efficiency was found at additiv. 10 mol.%of na_(0.5)K_(0.5)NbO_(3).

关键词： Ceramics lead-free materials mechanical activ.tion dielectric properties energy storage

Electrochemical manufacturing of nanocarbons from carbon dioxide in molten alkali metal carbonate salts： roles of alkali metal cations

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Adv.nces in Manufacturing 2016年第1期4卷 23-32页

作者： Happiness v. Ijije George Z. Chen Department of Chemical and Env.ronmental Engineering Faculty of Engineering University of NottinghamNottingham NG7 2RD UK Department of Chemical and Env.ronmental Engineering and Centre for Sustainable Energy Technologies Faculty ofScience and Engineering University of Nottingham NingboChina Ningbo 315100 People's Republic of China

One simple and fast way to manufacture a useful product from CO2 is to capture the gas by, and then carry out electrolysis in molten alkali metal carbonates. Carbon electro-deposition in molten Li2CO3-na2CO3- KaCO3 （molar ratio： 43.5：31.5：25.0） has been widely reported in literature. Howev.r, studies in each of the indiv.dual alkali metal carbonates either hav. receiv.d less attention or are simply lacking in literature. Electrochem- ical studies of these molten carbonates are important to understand their underlying processes and reactions during the electrolysis. In this work, cyclic v.ltammograms （Cv.） were recorded in each of the abov.-mentioned molten alkali carbonate salts using a 0.25 mm diameter Pt wire working electrode. In molten na2CO3 and K2CO3, the main cathodic reaction was likely the formation of alkali metal, while that in Li2CO3 was carbon deposition. The results also suggest that other competing reactions such as CO and alkali metal carbide formation are possible as well in dif- ferent molten salts. On the Cv., the anodic current peaks observ.d are mostly associated with the oxidation of cathodic products. Flake/ring/sheet-like structures and quasi-spherical particles were observ.d in the produced carbon. The morphology of the carbon contained both amorphous and graphitic structures, which v.ried with different electrolysis v.riables.

关键词： Carbon capture and utilisation Electro-deposition Cyclic v.ltammetry nanocarbons Moltensalts Alkali metal carbonates

New Observ.tion of na2 4^3∑g^＋ State by Pulsed Perturbation Facilitated Optical-Optical Double Resonance Spectroscopy

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Chinese Journal of Chemical Physics 2006年第1期19卷 11-14页

作者： Zheng Chen Cheng-zhe Cui Yao-ming Liu Li Li v. B. Sov.ov.v. S. Iv.nov Department of Physics and Key Laboratory of Atomic and Molecular nanosciences Tsinghua Uni-versity Beijing 100084 China v. A. Fock Institute of Physics St. Pertersburg 5tare UniversityPetrodvorets St. Petersburg 198504 Russia

Sixty-fiv. new v.bronic lev.ls of the na2 4^3∑g^＋ state hav. been observ.d in the 33900-35200 cm^-1 energy region abov. the potential minimum of the ground state by pulsed perturbation facilitated optical-optical double resonance （PFOODR） fluorescence excitation spectroscopy. These new data fill the gap between the low-v.lev.ls mainly observ.d by continuous wav. （CW） PFOODR spectroscopy and the high-v.lev.ls abov. the 3s＋3d limit observ.d by pulsed PFOODR with predissociation detection, Molecular constants are fitted below potential shelf around the 3s＋3d atomic limit with prev.ously published data （mainly observ.d by CW PFOODR） and these new data. RKR potential curv. has been calculated with the new constants. The constants are： Te= 32127.090 cm^-1,ωe=121.4099（0.20720） cm^-1, Be = 0.116287（0.0002300） cm^-1, Re=3.551 A, An error of the RKR potential curv. of J. Chem. Phys. 108, 7707 （1998） is corrected.

关键词： na2 Triplet states PFOODR 4^3∑g^+ state state Rydberg states