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A disk I/O optimized system for concurrent graph processing jobs

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Frontiers of Computer Science 2024年第3期18卷 13-29页

作者： Xianghao XU fang WANG Hong JIANG Yongli CHENG Dan FENG Peng fang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Department of Computer Science&Engineering University of Texas at ArlingtonArlingtonTX 76019USA College of Computer and Data Science Fuzhou UniversityFuzhou 350108China Zhejiang Lab Hangzhou 311121China

In order to analyze and process the large graphs with high cost efficiency,researchers have developed a number of out-of-core graph processing systems in recent years based on just one commodity *** the other hand,with the rapidly growing need of analyzing graphs in the real-world,graph processing systems have to efficiently handle massive concurrent graph processing(CGP)***,due to the inherent design for single graph processing job,existing out-of-core graph processing systems usually incur unnecessary data accesses and severe competition of I/O bandwidth when handling the CGP *** this paper,we propose GraphCP,a disk I/O optimized out-of-core graph processing system that efficiently supports the processing of CGP *** proposes a benefit-aware sharing execution model to share the I/O access and processing of graph data among the CGP jobs and adaptively schedule the graph data loading based on the states of vertices,which efficiently overcomes above challenges faced by existing out-of-core graph processing ***,GraphCP adopts a dependency-based future-vertex updating model so as to reduce disk I/Os in the future *** addition,GraphCP organizes the graph data with a Source-Sorted Sub-Block graph representation for better processing capacity and I/O access *** evaluation results show that GraphCP is 20.5×and 8.9×faster than two out-of-core graph processing systems GridGraph and GraphZ,and 3.5×and 1.7×faster than two state-of-art concurrent graph processing systems Seraph and GraphSO.

关键词： graph processing disk I/O concurrent jobs

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青钱柳子叶不定根的发生机制

林业科学 2009年第12期45卷 72-76页

作者：谢寅峰王莹张志敏方升佐王纪南京林业大学森林资源与环境学院南京210037

本文以青钱柳子叶为材料,WPM为基本培养基,研究不同质量浓度的外源ABA和IBA对子叶不定根发生的影响,并对不定根发生与内源激素的变化关系进行探讨。结果表明:添加0.5～5mg·mL-1IBA,对子叶不定根发生均有不同程度的促进作用,以1.5mg·m... 详细信息

本文以青钱柳子叶为材料,WPM为基本培养基,研究不同质量浓度的外源ABA和IBA对子叶不定根发生的影响,并对不定根发生与内源激素的变化关系进行探讨。结果表明:添加0.5～5mg·mL-1IBA,对子叶不定根发生均有不同程度的促进作用,以1.5mg·mL-1效果最佳,诱导生根率、平均生根条数和根长均达最大,生根率可达到100%;而添加0.01～0.5mg·mL-1ABA和不加激素的对照没有不定根的发生。内源激素的动态测定表明IAA对不定根的发生起关键性作用,根原基的启动需要较高的内源IAA,而不定根的形成与根的伸长需要相对较低的内源IAA水平。较高的IAA/ABA,IAA/GA3比值有利于不定根的发生,能较好反映出生根过程中内源激素间的平衡需求,GA3可能不是影响不定根发生的关键因素。研究结果为青钱柳生根诱导及其机制的研究提供依据。

关键词：青钱柳子叶不定根发生内源激素

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青钱柳幼胚愈伤组织的诱导

南京林业大学学报（自然科学版） 2012年第5期36卷 47-50页

作者：张金凤方升佐尚旭岚徐锡增南京林业大学森林资源与环境学院江苏南京210037

以青钱柳幼胚为外植体,研究了不同幼胚期、基本培养基种类、植物生长调节剂种类及其浓度配比对愈伤组织诱导的影响。结果表明,不同发育期的幼胚诱导出的愈伤组织在形态上差异较大,青钱柳种子发育至子叶胚中期较适合愈伤组织的诱导。青... 详细信息

以青钱柳幼胚为外植体,研究了不同幼胚期、基本培养基种类、植物生长调节剂种类及其浓度配比对愈伤组织诱导的影响。结果表明,不同发育期的幼胚诱导出的愈伤组织在形态上差异较大,青钱柳种子发育至子叶胚中期较适合愈伤组织的诱导。青钱柳幼胚愈伤诱导时基本培养基以改良DKW效果最佳,诱导率达到了88.89%,且无褐化现象;含2,4-D与KT组合的培养基较适宜愈伤组织的诱导,其中2,4-D(0.5 mg/L)+KT(2.0 mg/L)和2,4-D(1.0 mg/L)+KT(1.0 mg/L)的组合对青钱柳幼胚诱导愈伤组织效果最佳,诱导率分别为80.00%和78.33%。

关键词：青钱柳幼胚愈伤组织培养基植物生长调节剂

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不同密度杨树人工林的外源无机氮输入及土壤无机氮库研究

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南京林业大学学报（自然科学版） 2015年第4期39卷 69-74页

作者：燕亚飞田野方升佐宋浩囤兴建南京林业大学南方现代林业协同创新中心江苏南京210037 南京林业大学林学院江苏南京210037 河南科技大学林学院河南洛阳471003 山东省林业科学研究院山东济南250014

以江苏省泗洪县陈圩林场不同林分密度的‘南林95’杨（Populus＆#215;euramericana cv． Nanlin－95）人工林为试验林，利用原位离子交换树脂法对不同季节的外源无机氮输入量以及土壤0-20 cm的无机氮库进行测定。结果表明：外源无机氮... 详细信息

以江苏省泗洪县陈圩林场不同林分密度的‘南林95’杨（Populus＆#215;euramericana cv． Nanlin－95）人工林为试验林，利用原位离子交换树脂法对不同季节的外源无机氮输入量以及土壤0-20 cm的无机氮库进行测定。结果表明：外源无机氮输入量随着季节的变化均呈现出一定的变化规律，硝态氮在8-10月输入量较大，铵态氮2-4月输入量较高；高密度林分在5-10月之间的无机氮输入量比低密度林分的高。杨树人工林无机氮含量和无机氮库的变化趋势也呈现出季节变化规律，硝态氮含量在生长季节（5-10月）较高，铵态氮含量在11月较高，无机氮库总量在2月时最低；低密度林分无机氮库总量要低于高密度林分的无机氮库总量，8月时，两种密度林分的无机氮库有差异。

关键词：杨树人工林林分密度外源氮输入土壤无机氮库

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青钱柳叶三萜大孔吸附树脂纯化工艺

农业机械学报 2010年第9期41卷 143-147页

作者：吴彩娥方升佐徐琳杨万霞李婷婷贾韶千南京林业大学森林资源与环境学院南京210037

为研究大孔吸附树脂纯化青钱柳三萜的工艺,筛选了适宜的大孔吸附树脂,并通过静态和动态的吸附与解吸试验,确定了纯化工艺参数。结果表明,在供试的3种大孔吸附树脂中,D-101型大孔吸附树脂适合分离青钱柳叶三萜,其吸附量和解吸率分别为57.... 详细信息

为研究大孔吸附树脂纯化青钱柳三萜的工艺,筛选了适宜的大孔吸附树脂,并通过静态和动态的吸附与解吸试验,确定了纯化工艺参数。结果表明,在供试的3种大孔吸附树脂中,D-101型大孔吸附树脂适合分离青钱柳叶三萜,其吸附量和解吸率分别为57.5 mg/g和96.51%;动态吸附青钱柳叶三萜时的最适宜进样流速与进样质量浓度分别为2 BV/h和1.5 mg/mL;动态解吸时洗脱剂的最适宜体积分数与洗脱速度分别为50%乙醇和2 BV/h。经大孔吸附树脂分离纯化后三萜的纯度是粗提物的4.1倍,得率为74.66%,表明D-101型大孔吸附树脂纯化青钱柳三萜效果较佳。

关键词：青钱柳三萜大孔吸附树脂纯化

Planning an adaptive reuse development of underutilized urban underground infrastructures:A case study of Qingdao,China

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Underground Space 2024年第1期14卷 18-33页

作者： Yong-Kang Qiao fang-Le Peng Yun-Hao Dong Chun-fang Lu Research Center for Underground Space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Urban underground infrastructures(UUIs)are a vital component of built capital for urban ***,many cities are now home to a multitude of disused or underutilized UUIs,not least aged purpose-built underground facilities,causing a waste of valuable underground space resource *** the process of urban renewal,adaptive reuse can be an attractive solution to breathe new life into underutilized UUIs,while addressing some of the modern problems of the built environment by an economically feasible ***,there is a prevalent absence in the current literature of the overarching planning and decision-making approaches for an adaptive reuse development of underutilized *** the intention of addressing this shortfall,this paper first lays out development strategies,then sets the generic patterns for adaptive reuse of disused or underutilized *** the city of Qingdao,China as a case study,detailed planning and decision-making approaches with the aid of multi-source data and spatial analysis tools are *** is anticipated that the findings of this research will assist the adaptive reuse development of UUIs in providing theoretical guidance and empirical evidence,thereby enhancing the role of urban underground space use in contributing to urban revitalization and urban sustainability.

关键词： Urban underground infrastructures Underutilized Adaptive reuse Planning Urban renewal

A low-frequency and broadband wave-insulating vibration isolator based on plate-shaped metastructures

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Applied Mathematics and Mechanics(English Edition) 2024年第7期45卷 1171-1188页

作者： Wei WEI Feng GUAN Xin fang College of Intelligent Science National University of Defense TechnologyChangsha410073China Naval Research Academy Beijing100161China

A metamaterial vibration isolator,termed as wave-insulating isolator,is proposed,which preserves enough load-bearing capability and offers ultra-low and broad bandgaps for greatly enhanced wave *** consists of plate-shaped metacells,whose symmetric and antisymmetric local resonant modes offer several low and broad mode bandgaps although the complete bandgap remains high and *** bandgap mechanisms,vibration isolation properties,effects of key parameters,and robustness to complex conditions are *** experimentally demonstrated,the wave-insulating isolator can improve the vibration insulation in the ranges of[50 Hz,180 Hz]and[260 Hz,400 Hz]by 15 dB and 25 dB,respectively,in contrast to the conventional isolator with the same first resonant frequency.

关键词： metamaterial and metastructure vibration isolation bandgap wave insulation plate

Non-dimensional analysis on blast wave propagation in foam concrete:Minimum thickness to avoid stress enhancement

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Defence Technology（防务技术） 2024年第6期36卷 30-46页

作者： Ya Yang Xiangzhen Kong Qin fang State Key Laboratory of Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007JiangsuChina

Foam concrete is a prospective material in defense engineering to protect structures due to its high energy absorption capability resulted from the long plateau ***,stress enhancement rather than stress mitigation may happen when foam concrete is used as sacrificial claddings placed in the path of an incoming blast *** investigate this interesting phenomenon,a one-dimensional difference model for blast wave propagation in foam concrete is firstly proposed and numerically solved by improving the second-order Godunov *** difference model and numerical algorithm are validated against experimental results including both the stress mitigation and the stress *** difference model is then used to numerically analyze the blast wave propagation and deformation of material in which the effects of blast loads,stress-strain relation and length of foam concrete are *** particular,the concept of minimum thickness of foam concrete to avoid stress enhancement is ***,non-dimensional analysis on the minimum thickness is conducted and an empirical formula is proposed by curve-fitting the numerical data,which can provide a reference for the application of foam concrete in defense engineering.

关键词： Foam concrete Blast wave propagation Non-dimensional analysis Stress enhancement

A New Method for Solving Nonlinear Partial Differential Equations Based on Liquid Time-Constant Networks

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Journal of Systems Science & Complexity 2024年第2期37卷 480-493页

作者： SUN Jiuyun DONG Huanhe fang Yong College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

In this paper,physics-informed liquid networks(PILNs)are proposed based on liquid time-constant networks(LTC)for solving nonlinear partial differential equations(PDEs).In this approach,the network state is controlled via ordinary differential equations(ODEs).The significant advantage is that neurons controlled by ODEs are more expressive compared to simple activation *** addition,the PILNs use difference schemes instead of automatic differentiation to construct the residuals of PDEs,which avoid information loss in the neighborhood of sampling *** this method draws on both the traveling wave method and physics-informed neural networks(PINNs),it has a better physical ***,the KdV equation and the nonlinear Schr¨odinger equation are solved to test the generalization ability of the *** the best of the authors’knowledge,this is the first deep learning method that uses ODEs to simulate the numerical solutions of PDEs.

关键词： Nonlinear partial differential equations numerical solutions physics-informed liquid networks physics-informed neural networks