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期刊论文 15

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Hadoop，NameNode，元数据，保留位置的哈希，一致性哈希， 1

一致性哈希表；副本布局；能源管理；键值存储系统；可靠性 1

区块链；共识协议；一致性哈希；低能耗；去中心化 1

轨道交通；资产能源化；自然禀赋；自洽供给；融合发展 1

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Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam

Iman FATTAHI, Hamid Reza MIRDAMADI, Hamid ABDOLLAHI

《结构与土木工程前沿（英文）》 2020年第14卷第3期页码 675-689 doi: 10.1007/s11709-020-0625-4

摘要： Analyzing static and dynamic problems including composite structures has been of high significance in research efforts and industrial applications. In this article, equivalent single layer approach is utilized for dynamic finite element procedures of 3D composite beam as the building block of numerous composite structures. In this model, both displacement and strain fields are decomposed into cross-sectional and longitudinal components, called consistent geometric decomposition theorem. Then, the model is discretized using finite element procedures. Two local coordinate systems and a global one are defined to decouple mechanical degrees of freedom. Furthermore, from the viewpoint of consistent geometric decomposition theorem, the transformation and element mass matrices for those systems are introduced here for the first time. The same decomposition idea can be used for developing element stiffness matrix. Finally, comprehensive validations are conducted for the theory against experimental and numerical results in two case studies and for various conditions.

关键词： composite beam dynamic finite element degrees of freedom coupling experimental validation numerical validation

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Analysis of actuating mechanics characteristics for a flexible miniature robot system

YU Lianzhi, YAN Guozheng, MA Guanying, ZAN Peng

《机械工程前沿（英文）》 2008年第3卷第1期页码 66-70 doi: 10.1007/s11465-008-0006-5

摘要： Based on the inchworm movement, a miniature endoscope inspection robot system with a flexible structure is designed. The system is actuated by a pneumatic rubber actuator with three degrees of freedom, and it holds its position by air chambers. The actuating mechanics characteristics of the robot are analyzed. An electro-pneumatic pressure system is designed to control the motion of the robot. Results of the calculation and experiments are consistent, and the robot system can move smoothly in a soft tube.

关键词： calculation consistent endoscope inspection electro-pneumatic miniature endoscope

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Combustion instability detection using the wavelet detail of pressure fluctuations

JI Junjie, LUO Yonghao

《能源前沿（英文）》 2008年第2卷第1期页码 116-120 doi: 10.1007/s11708-008-0019-0

摘要： A combustion instability detection method that uses the wavelet detail of combustion pressure fluctuations is put forward. To confirm this method, combustion pressure fluctuations in a stoker boiler are recorded at stable and unstable combustion with a pressure transducer. Daubechies one-order wavelet is chosen to obtain the wavelet details for comparison. It shows that the wavelet approximation indicates the general pressure change in the furnace, and the wavelet detail magnitude is consistent with the intensity of turbulence and combustion noise. The magnitude of the wavelet detail is nearly constant when the combustion is stable, however, it will fluctuate much when the combustion is unstable.

关键词： comparison wavelet approximation pressure transducer general pressure consistent

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Parametric analysis and design equation of ultimate capacity for unstiffened overlapped CHS K-joints

CHEN Yu, ZHAO Xianzhong, CHEN Yiyi

《结构与土木工程前沿（英文）》 2008年第2卷第2期页码 107-115 doi: 10.1007/s11709-008-0014-x

摘要： A finite element model simulating an experiment on unstiffened, overlapped circular hollow structure (CHS) K-joints was generated and validated by comparing the ultimate capacities, deformation processes and failure modes of the experimental results. Using this model, the stress distribution, propagation of plasticity and the failure modes of overlapped joints with through-brace-in-compression and welded hidden seams were analyzed. The effect of geometric parameters, with or without hidden welds, and the loading hierarchy reversal of braces on the ultimate capacity of the joints were also studied. The results of finite element parametric analysis indicate that the brace-to-chord thickness ratio has relatively large effects on the failure mechanism and ultimate capacity of overlapped joints. It was also found that the absence of hidden welds has less significance on the ultimate capacity of through-brace-in-compression joints than through-brace-in tension joints. Finally, based on the design equation of gap joints, a formula predicting the ultimate capacity of overlapped CHS K-joints was derived by applying multivariate regression analysis. Results from the proposed design equation are consistent with experimental results.

关键词： regression analysis consistent unstiffened plasticity overlapped

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一种针对基于一致性哈希的键值存储系统的低能耗副本布局策略 Article

Nan-nan ZHAO,Ji-guang WAN,Jun WANG,Chang-sheng XIE

《信息与电子工程前沿（英文）》 2016年第17卷第10期页码 994-1007 doi: 10.1631/FITEE.1601162

摘要：概要：分布式键值存储作为最常用的分布式存储系统之一，目前广泛部署在大规模数据中心中。然而，大规模数据中心的高能耗是一个亟待解决的问题。为达到较好节能效果，同时满足数据可用性要求，本文提出一个针对基于一致性哈希的分布式键值存储系统的低能耗副本布局策略——GreenCHT，它包括一个分层副本布局方案、一个可靠的分布式日志和一个预测能耗模式调节器。GreenCHT将副本分布在互不重叠的多个节点层，而非随机放置于哈希环的部分节点。在分层副本布局中，部分节点层可以维持活动状态，其他节点可以被关闭而不影响数据可用性，以达到节能目的。能耗模式调节器（power mode scheduler, PMS）能够预测I/O负载，并根据负载高低波动变化，相应关闭或开启某些节点层。为保证节能状态下的系统可靠性，对于待机副本的写请求，被重新映射到活动的服务器，以保证系统的容错性。通过修改Sheepdog原有的数据分布算法和副本布局策略，GreenCHT被配置在Sheepdog存储集群中。实验中，GreenCHT能够节省35%–61%能耗，同时维持较好性能和可靠性。

关键词：一致性哈希表；副本布局；能源管理；键值存储系统；可靠性

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The kinetic study of light alkene syntheses by CO 2 hydrogenation over Fe-Ni catalysts

Yaling ZHAO, Li WANG, Xiwei HAO, Jiazhou WU,

《化学科学与工程前沿（英文）》 2010年第4卷第2期页码 153-162 doi: 10.1007/s11705-009-0241-2

摘要： A kinetics model of CO hydrogenation over iron-nickel catalysts was developed based on the detailed mechanism of alkenes re-adsorption and secondary reaction. The corresponding kinetical experiments are conducted in a continuous fixed bed reactor. The effect of reaction conditions on catalyst performance was analyzed according to the results of orthogonal experiments. The results of the experiments show that more methane in products can be obtained with iron-nickel catalysts, the trend of which is consistent with the thermodynamic analysis. However, the content of alkenes in products is equivalent with that of alkanes. This shows that the reaction is controlled by kinetics. In all, the results of the experiments also substantiate that the model can give a good representation of the reaction mechanism of CO hydrogenation over iron-nickel catalysts. The parameters of this model give a better explanation for the question why the iron-nickel catalysts have a higher selectivity toward alkenes compared with other iron-based catalysts.

关键词： representation corresponding orthogonal thermodynamic consistent

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Lifting installation and prestressed cable construction of suspendome roof for Wuhan Gymnasium

GUO Zhengxing, SHI Kairong, LUO Bin, TIAN Qiliang, WU Julong, BI Shuiyong

《结构与土木工程前沿（英文）》 2008年第2卷第1期页码 87-92 doi: 10.1007/s11709-008-0005-y

摘要： The steel roof of Wuhan Gymnasium is a long-span suspendome structure system. According to the structural characteristics of the roof, the lifting installation of upper latticed shell and the installation and tension of lower prestressed cables are introduced in detail. The cable tension is completed successfully on June 27, 2006, while the test results of cable forces and structural deformation are comparatively consistent with the theoretical analysis results. Moreover, Strut-adjustment Method is innovated and applied successfully in the construction of long-span suspendome structure for the first time, and the theoretical and practical experiences can be used for the research and application of similar new-type spatial structures.

关键词： practical new-type installation consistent Gymnasium

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Separation of gibberellic acid (GA3) by macroporous adsorption resins

WANG Ruifang, YANG Jialing, SHI Zuoqing, OU Lailiang

《化学科学与工程前沿（英文）》 2008年第2卷第2期页码 171-175 doi: 10.1007/s11705-008-0025-0

摘要： The adsorption effects of several macroporous adsorption resins for gibberellic acid (GA3) were investigated. The dynamic adsorption capacity is 58.38 mg/g dry beads for resin R4 and 96.46 mg/g dry beads for resin R5 which is consistent with the surface area. Aqueous methanol (50%, V/V) is a good eluent and the yield of GA3 is above 95%. The concentration of GA3 could increase five-fold after an adsorption-elution cycle and this is important when considering further crystallization of GA3 in an industrial process.

关键词： industrial gibberellic adsorption capacity crystallization consistent

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Measurement of activity coefficients at infinite dilution for hydrocarbons in imidazolium-based ionic liquids and QSPR model

ZHU Jiqin, YU Yanmei, CHEN Jian, FEI Weiyang

《化学科学与工程前沿（英文）》 2007年第1卷第2期页码 190-194 doi: 10.1007/s11705-007-0035-3

摘要： The separations of olefin/paraffin, aromatic/aliphatic hydrocarbons or olefin isomers using ionic liquids instead of volatile solvents have interested many researchers. Activity coefficients γ at infinite dilution of a solute in ionic liquid are generally used in the selection of solvents for extraction or extractive distillation. In fact, the measurement of γ by gas-liquid chromatography is a speedy and cost-saving method. Activity coefficients at infinite dilution of hydrocarbon solutes, such as alkanes, hexenes, alkylbenzenes, styrene, in 1-allyl-3-methylimidazolium tetrafluoroborate ([AMIM][BF]) and 1-butyl-3-methyl imidazolium hexafluorophosphate ([BMIM][PF6]), 1-isobutenyl-3-methylimidazolium tetrafluoroborate ([MPMIM][BF]) and [MPMIM][BF]-AgBF have been determined by gas-liquid chromatography using ionic liquids as stationary phase. The measurements were carried out at different temperatures from 298 to 318 K. The separating effects of these ionic liquids for alkanes/hexane, aliphatic hydrocarbons/benzene and hexene isomers have been discussed. The hydrophobic parameter, dipole element, frontier molecular orbital energy gap and hydration energy of these hydrocarbons were calculated with the PM3 semi-empirical quantum chemistry method. The quantitative relations among the computed structure parameters and activity coefficients at infinite dilution were also developed. The experimental activity coefficient data are consistent with the correlated and predicted results using QSPR models.

关键词： cost-saving consistent coefficient measurement separating

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“双碳”目标下轨道交通与能源融合发展路径和策略研究

贾利民,程鹏,张蜇,吉莉,徐春梅

《中国工程科学》 2022年第24卷第3期页码 173-183 doi: 10.15302/J-SSCAE-2022.03.018

摘要：

轨道交通是能源消耗和碳排放的重要行业，推进轨道交通能源结构变革和以能源自洽为特征的新型轨道交通能源系统发展是助力实现碳达峰、碳中和目标的重要手段。本文在分析轨道交通与能源融合发展需求的基础上，总结了轨道交通与能源融合的发展现状和发展趋势，从太阳能、风能等方面分析了轨道交通与能源融合发展的自然禀赋情况；根据电气化和非电气化轨道交通特点，提出了通过交通资产能源化充分利用可再生能源自然禀赋，实现新时代轨道交通能源融合发展的关键技术路径；最后，基于轨道交通新能源自洽供给潜力评估，提出了轨道交通与能源融合的系列场景和方式，最终形成了以轨道交通自洽能源系统构建为目标的轨道交通与能源融合的发展路线图和对策建议。研究建议：鼓励绿色智能轨道交通技术创新，构建轨道交通能源融合技术体系；实施核心科技攻关计划，统筹新能源与轨道交通产业布局；政策引领轨道交通能源融合发展，建立绿色金融政策保障体系。

关键词：轨道交通；资产能源化；自然禀赋；自洽供给；融合发展

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Space-time evolution rules study on acoustic emission location in rock under cyclic loading

Jiang XU, Shuchun LI, Yunqi TAO, Yongdong JIANG, Xiaojun TANG,

《结构与土木工程前沿（英文）》 2009年第3卷第4期页码 422-427 doi: 10.1007/s11709-009-0056-8

摘要： An acoustic emission (AE) location experiment was performed on sandstone using an advanced AE test system. The space-time evolution rule regarding damage was analyzed under cyclic loading as well as AE. The results show that AE on static loading process is consistent with the damage evolution rule of compression and the elastic-plastic deformation phase; at the beginning of cyclic loading with low duration time and energy, AE events came from a small crack. The location result showed that most events occurred in the core zone forming at the static loading process, and the location points changed slowly. AE energy changed little during the metaphase of cyclic process. There was a modest increase of location points in every cycle. The tendency of steady development could be predicted from the AE location events. At the end of each cyclic loading, the quantity of AE events and energy increased quite rapidly, reaching a maximum at the last cycle. AE events had high energy and duration time. Location events changed quite rapidly and assembled and linked continuously in the core zone. At the same time, they expanded to the top of specimen. A macroscopic crack finally formed. In the postfailure process, some AE events still existed due to fracturing of gliding friction. Owing to the inner stress balance of rock even after loading stopped, minor AE events still occurred.

关键词： location result AE location consistent friction elastic-plastic deformation

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Estimation of thermodynamic properties of the ternary molten salt system, LiF-NaF-BeF2, by the modified Peng-Robinson equation

ZHANG Dalin, QIU Suizheng, SU Guanghui, JIA Dounan

《能源前沿（英文）》 2007年第1卷第2期页码 174-180 doi: 10.1007/s11708-007-0022-x

摘要： The molten salt reactor (MSR), which is one of the generation IV reactors, can meet the demand of transmutation and breeding. The thermodynamic properties of the molten salt system like LiF-NaF-BeF2 influence the design and construction of the fuel salt and coolant in the MSR for the new generation. In this paper, the equation of state of the ternary system 15%LiF-58%NaF-27%BeF, over the temperature range from 873.15 to 1 073.15 K at one atmosphere pressure, is described using a modified Peng-Robinson (PR) equation. The densities of the ternary system and its components are estimated by this equation directly, and compared with the experimental data. Based on the equation of state, the other thermodynamic properties such as the enthalpy, entropy and heat capacity at constant pressure are estimated by the residual function method and the fugacity coefficient method respectively. The densities calculated by PR equation are highly in agreement with the experimental data, and the enthalpy, entropy and heat capacity evaluated by the two different methods are consistent with each other. It can be concluded that the modified PR equation can be applied to evaluate the density of the molten salt system, and it is recommended that it be used as the basis to estimate the enthalpy, entropy and heat capacity of the molten salt system.

关键词： modified Peng-Robinson coolant consistent MSR entropy

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Dr. Hadoop: Hadoop的一种无限可扩展元数据管理机制—小象如何不老？

Dipayan DEV,Ripon PATGIRI

《信息与电子工程前沿（英文）》 2016年第17卷第1期页码 15-31 doi: 10.1631/FITEE.1500015

摘要：

在这个Exa字节标度时代，数据以指数速率增长。反过来，这会在文件系统中生成大量的元数据。 Hadoop是处理大数据的最广泛使用的框架。然而，由于大量元数据的增长，Hadoop的效率受到许多研究人员的质疑。因此，为Hadoop创建高效且可扩展的元数据管理至关重要。基于哈希的映射和子树分区适用于分布式元数据管理方案。子树分区不能在元数据服务器之间均匀地分配工作负载，并且需要迁移元数据以保持负载大致平衡。尽管基于散列的映射在Hadoop的元数据服务器即NameNode之间均匀分配负载，但基于散列的映射仍受到元数据局部性的限制。在本文中，我们提出了一种称为动态循环元数据拆分（DCMS）的循环元数据管理机制。 DCMS使用一致的哈希和保留位置的哈希来保留元数据的位置，保留复制的元数据以实现出色的可靠性，并在NameNode之间动态分配元数据以保持负载平衡。 NameNode是Hadoop的中央心脏。保留所有文件的目录树，所有文件的失败都会导致单点故障（SPOF）。 DCMS删除了Hadoop的SPOF，并提供了有效且可扩展的元数据管理。新框架名为“ Dr. Dr. Hadoop”（作者姓名之后）。

关键词： Hadoop，NameNode，元数据，保留位置的哈希，一致性哈希，

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Synthesis of copolymers of 3-acryloyloxymethyl-3′-methyloxetane and 3-(2-(2-(2-Methoxyethylenoxy)ethylenoxy)ethylenoxy)-3′-methyloxetane and their ionic conductivity properties

YE Lin, ZHAO Yumei, FENG Zengguo, BAI Ying, WU Feng

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 343-348 doi: 10.1007/s11705-007-0062-0

摘要： An oxetane-derived monomer, 3-acryloyloxymethyl-3′-methyloxetane (AMO) was prepared from the reaction of 3-hydromethyl-3-methyloxetane with acryloyl chloride. The cationic ring-opening copolymerization of AMO with another oxetane-derived monomer, 3-(2-(2-(2-methoxyethylenoxy)ethylenoxy)ethylenoxy)-3′-methyloxetane (MEMO) was conducted in CHCl solution using BF3 ·OEt/1, 4-butanediol as a co-initiator. The resulting copolymers were characterized by FTIR, H NMR and Gel Permeation Chromatography (GPC) analyses, and it was found that the enchained ratio of AMO in the copolymers is far lower than its feed ratio. They were crosslinked via the radical polymerization of the vinyl group initiated by BPO after doping with lithium trifluoromethanesulfonimide (LiTFSI) to give rise to tough polymeric electrolyte films. The ionic conductivity was measured at varying content of AMO and different concentration of lithium salt LiTFSI by AC impedance, and a maximum ion conductivity of 1.44×10 S/cm at 30°C or 1.25×10 S/cm at 80°C was attained in the sample PAM 33 at the mole ratio of O : Li = 20. The DSC results indicated that decreases with the increase of the proportion of AMO in the copolymer, well consistent with the ion conductivity trend. The TGA (thermogravimetric analysis) measurement revealed that this kind of copolymer electrolytes is more thermostable than their liquid counterparts.

关键词： 4-butanediol 2-methoxyethylenoxy consistent oxetane-derived copolymer

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基于一致性哈希算法的低能耗共识协议 Research Article

Lei Yu, Xiao-fang Zhao, Yan Jin, Heng-yi Cai, Bo Wei, Bin Hu,yulei@ncic.ac.cn

《信息与电子工程前沿（英文）》 2019年第20卷第10期页码 1361-1377 doi: 10.1631/FITEE.1800119

摘要：当前区块链共识协议在去中心化、安全性和能耗方面存在“三难”优化困境。针对这个问题，基于一致性哈希算法，设计了两个新的区块链共识协议，分别为CHB-consensus和CHBD-consensus。在新的共识协议下，诚实的“矿工”可以公平地获得创建新区块的机会。在创建新块时，诚实矿工不再需要付出海量竞争性算力，且该新区块可获取整个区块链网络公平验证及确认共识协议。恶意矿工则必须付出海量算力资源才能攻击新区块，以创建特权或实现“双花”。由CHB-consensus和CHBD-consensus共识形成的区块链网络基于与比特币系统相同的安全性假设，在节省海量电力的同时，不会牺牲去中心化和安全性。分析了可能的攻击行为，并给出严格但可调整的验证策略。CHB-consensus和CHBD-consensus共识引入数字身份证书管理机构（CA），CA对区块链网络或区块链数据结构没有特殊管理权或控制权，但依据CA系统信誉和可靠性，存在一定隐私泄露风险。最后，分析了CHB-consensus和CHBD-consensus共识的鲁棒性和能耗，并通过理论推导证明它们的优势。

关键词：区块链；共识协议；一致性哈希；低能耗；去中心化

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标题作者时间类型操作

Application of consistent geometric decomposition theorem to dynamic finite element of 3D composite beam

Iman FATTAHI, Hamid Reza MIRDAMADI, Hamid ABDOLLAHI

期刊论文

Analysis of actuating mechanics characteristics for a flexible miniature robot system

YU Lianzhi, YAN Guozheng, MA Guanying, ZAN Peng

期刊论文

Combustion instability detection using the wavelet detail of pressure fluctuations

JI Junjie, LUO Yonghao

期刊论文

Parametric analysis and design equation of ultimate capacity for unstiffened overlapped CHS K-joints

CHEN Yu, ZHAO Xianzhong, CHEN Yiyi

期刊论文

一种针对基于一致性哈希的键值存储系统的低能耗副本布局策略

Nan-nan ZHAO,Ji-guang WAN,Jun WANG,Chang-sheng XIE

期刊论文

The kinetic study of light alkene syntheses by CO 2 hydrogenation over Fe-Ni catalysts

Yaling ZHAO, Li WANG, Xiwei HAO, Jiazhou WU,

期刊论文

Lifting installation and prestressed cable construction of suspendome roof for Wuhan Gymnasium

GUO Zhengxing, SHI Kairong, LUO Bin, TIAN Qiliang, WU Julong, BI Shuiyong

期刊论文

Separation of gibberellic acid (GA3) by macroporous adsorption resins

WANG Ruifang, YANG Jialing, SHI Zuoqing, OU Lailiang

期刊论文

Measurement of activity coefficients at infinite dilution for hydrocarbons in imidazolium-based ionic liquids and QSPR model

ZHU Jiqin, YU Yanmei, CHEN Jian, FEI Weiyang

期刊论文

“双碳”目标下轨道交通与能源融合发展路径和策略研究

贾利民,程鹏,张蜇,吉莉,徐春梅

期刊论文

Space-time evolution rules study on acoustic emission location in rock under cyclic loading

Jiang XU, Shuchun LI, Yunqi TAO, Yongdong JIANG, Xiaojun TANG,

期刊论文

Estimation of thermodynamic properties of the ternary molten salt system, LiF-NaF-BeF2, by the modified Peng-Robinson equation

ZHANG Dalin, QIU Suizheng, SU Guanghui, JIA Dounan

期刊论文

Dr. Hadoop: Hadoop的一种无限可扩展元数据管理机制—小象如何不老？

Dipayan DEV,Ripon PATGIRI

期刊论文

Synthesis of copolymers of 3-acryloyloxymethyl-3′-methyloxetane and 3-(2-(2-(2-Methoxyethylenoxy)ethylenoxy)ethylenoxy)-3′-methyloxetane and their ionic conductivity properties

YE Lin, ZHAO Yumei, FENG Zengguo, BAI Ying, WU Feng

期刊论文

基于一致性哈希算法的低能耗共识协议

Lei Yu, Xiao-fang Zhao, Yan Jin, Heng-yi Cai, Bo Wei, Bin Hu,yulei@ncic.ac.cn

期刊论文

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