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超大直径泥水平衡盾构地表沉降控制关键技术

上海交通大学学报 2011年第S1期45卷 124-127页

作者：何国军上海隧道工程股份有限公司上海200082

分析泥水平衡盾构施工引起地表沉降的机理,结合超大直径泥水平衡盾构施工实例,从切口压力、泥水指标控制及同步注浆管理等方面探讨超大直径泥水平衡盾构施工地表沉降的控制技术.结果表明:切口压力的设定对正面土体沉降量影响较大,在施... 详细信息

分析泥水平衡盾构施工引起地表沉降的机理,结合超大直径泥水平衡盾构施工实例,从切口压力、泥水指标控制及同步注浆管理等方面探讨超大直径泥水平衡盾构施工地表沉降的控制技术.结果表明:切口压力的设定对正面土体沉降量影响较大,在施工过程中应密切关注切口位置的地表沉降量并及时调整压力.对于超大直径泥水平衡盾构,单次压力调整不宜过大,切口压力波动不宜超过±2 kPa;采用"双控"同步注浆模式,以砂与粉煤灰为主要原材料的单液浆施工技术可以有效减小地表后期的沉降.

关键词：超大直径泥水平衡盾构沉降控制施工技术

钢-连续纤维复合筋(SFCB)力学性能试验研究与理论分析

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土木工程学报 2010年第3期43卷 53-61页

作者：吴刚罗云标吴智深胡显奇张敏东南大学浙江石金玄武岩纤维有限公司北京特希达技术研发有限公司

本文对工业化制备的钢-连续纤维复合筋(SFCB)制品进行了单向拉伸和反复拉伸试验,观察其破坏过程和破坏特征,测定其初期刚度、二次刚度、屈服强度、极限强度、卸载刚度、残余变形。试验结果表明,SFCB的荷载-应变关系曲线在纤维断裂前呈... 详细信息

本文对工业化制备的钢-连续纤维复合筋(SFCB)制品进行了单向拉伸和反复拉伸试验,观察其破坏过程和破坏特征,测定其初期刚度、二次刚度、屈服强度、极限强度、卸载刚度、残余变形。试验结果表明,SFCB的荷载-应变关系曲线在纤维断裂前呈现出明显的双折线,钢筋屈服后SFCB具有稳定的二次刚度、小的残余变形和良好的可恢复性能。根据材料的复合法则推导出了SFCB单调加载下应力-应变关系的理论计算模型,针对根据现有钢筋和纤维材料恢复力模型直接采用复合法则得到的SFCB反复拉伸的理论模型和试验结果误差较大的情况,基于SFCB反复拉伸的荷载-应变试验曲线特征,经过统计分析,构建了SFCB反复拉伸下应力-应变关系恢复力模型,该模型良好地揭示了SFCB在反复加载下其卸载模量随塑性发展而逐渐退化的规律,与试验数据进行比较,发现均吻合较好,证明了可以通过理论计算对SFCB的力学性能进行预测和设计。

关键词：钢-连续纤维复合筋(SFCB) 力学性能反复加载试验研究理论分析

Studies on Neural Network Modeling for Air co.ditioning System by Using Data Mining with Association Analysis

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Studies on Neural Network Modeling for Air Conditioning Syst...

High Temperature Oxidation Behavior of Nitride Bonded SiC Based Refractories

2010 4th International co.ference on Intelligent Information Technology Application (IITA2010)

作者： Zheng Wang School of Technology, beijing Forestry University, beijing, china Ning Han School of Technology, beijing Forestry University, beijing, china Yang Wang beijing Master Systems engineering co.,ltd beijing, china

VAV air co.ditioning system involves multiple co.trol parameters and they have strong co.pling with each other, which caused the modeling co.plex. A neural network model of air handling unit （AHU） is co.structed through data preprocessing and association analysis as mean of data mining is made to identity interesting information between the supply air temperature and the other variables acquired by air co.ditioning system. The study provides new idea and technical support for AHU modeling of VAV air co.ditioning system.

关键词： VAV air co.ditioning system data mining association analysis neural network modeling

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china's Refractories 2012年第1期21卷 31-35页

作者： WANG Li1,2,JIANG Mingxue1 1 School of Materials Science and engineering,Xi’an University of Architecture and Technology,Xi’an 710055,china 2 Sinosteel Refractory co. ,ltd. ,Luoyang 471039,china School of Materials Science and engineering Xi'an University of Architecture and Technology Xi'an 710055 China Sinosteel Refractory co. Ltd Luoyang 471039 China

High temperature oxidation behavior of two kinds of nitride bonded SiC based refractories wtls bwestigated at I 100-1 .500℃ by means of X-ray di[fractometer, scanning electronic microsco.y and thermogravimetry. The results show that ：（1） with the temperature im＇reasing, the oxidation mass increment rote of the specimen *** and then. decreases, and oxidation passi＇va tion occttrs; （2） the oxidation resistance of SiAION bonded SiC refractories is superior to that of Si3N4 botlded SiC refractories ; （3） high temperature oxidtttion resuits itt the increase of co.pressive strength at room temperature of SiC based refractoviesiaes co.lmred with specimen before oxidatiotl; the co.pressive strength of SIMON bonded SiC specimens oxidized at high temperatures decreases with the increase of the temperature as a result of formation amt burst of surfhce bubble, while the decrease of co.pressive strength of Sign4 bonded SiC specimens oxidized at high temperatures is owitng to the bwrease of the co.sistency of netlike crack assoeiated with cristobalite transfornuttion during co.ling.

关键词： silico. carbide based refractories oxidalion hehavior bonding phase SiAION silico. nitride

Ubiquitous Access Technology for Wireless Digital Home Networks

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ZTE co.munications 2006年第4期4卷 40-46页

作者： Peng Mugen 1Jiang Yong 2Wang Wenbo 1(1. School of Teleco.munication engineering, beijing University of Posts and Teleco.munications, beijing 100876, china 2. china Potevio co., ltd., beijing 100053, china) china china

As an important branch of teleco.munication technology, digital home networks have quickly developed in recent years. Although architecture of the digital home network based on teleco.munication networks has been standardized in china, only wireless access is defined to be allowable. Therefore, it beco.es the focus of further research how to establish a wireless digital home network. This article proposes the co.cept and shows the architecture of ubiquitous access for wireless digital home networks. Moreover, key technologies for ubiquitous access are discussed here, including co.nitive radio, the co.cept of wireless Mesh, generic link transfer mechanism, Quality of Service (QoS) guarantee mechanism, Electromagnetic co.patibility (EMC) and co.xistence of heterogeneous systems.

关键词： Access Ubiquitous Access Technology for Wireless Digital Home Networks WPAN Home

A quick evaluation model for co.2 flooding and sequestration

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Petroleum Science 2010年第4期7卷 515-523页

作者： Yao Yuedong Ji Zemin Key Laboratory of Petroleum engineering Ministry of Education China University of Petroleum Beijing 102249 China

co. flooding not only triggers an increase in oil production,but also reduces the amount of co. released to the atmosphere （by storing it permanently in the formations）.It is one of the best ways to use and store *** paper firstly selects the key factors after analyzing the factors influencing the co. storage potential in the formations and oil reco.ery,and then introduces a series of dimensionless variables to describe reservoir *** influencing factors with varying values are calculated through a Box-Behnken experimental *** results are interpreted by a response surface method,and then a quick screening model is obtained to evaluate the oil reco.ery and co. storage potential for an oil *** on the evaluation model,sensitivity analysis of each factor is carried ***,research on co. sequestration and flooding in a typical reservoir indicates that the evaluation model fits well with the numerical simulation,which proves that the evaluation model can provide criteria for screening attractive candidate reservoirs for co. sequestration and flooding.

关键词： Evaluation model enhanced oil reco.ery co. sequestration Box-Behnken design response surface method

Change of asphaltene and resin properties after catalytic aquathermolysis

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Petroleum Science 2009年第2期6卷 194-200页

作者： Yi Yufeng Li Shuyuan Ding Fuchen Yu Hang School of Chemical Science and engineering China University of Petroleum （Beijing） Beijing 102249 China School of Chemical engineering Beijing Institute of Petrol-chemical Technology Beijing 102617 China

Resin and asphaltene were separated from Liaohe heavy oil. Catalytic aquathermolysis of asphaltene and resin was investigated by using water soluble catalysts （NiSO4 and FeSO4） and oil soluble catalysts （nickel naphthenate and iron naphthenate）. Before and after aquathermolysis, the properties of the resin and asphaltene was co.pared by means of ultimate analysis, vapor pressure osmometer （VPO） average molecular weight, X-ray diffraction （XRD）,^13C and ^1H nuclear magnetic resonance （NMR）. The co.version sequence was as follows： No-catalyst〈NiSO4〈FeSO4〈nickel naphthenate〈iron naphthenate. In the presence of catalysts, the amount of H2 and co.increased significantly, while H2S in the gas product decreased. The molecular weight of asphaltene and resin increased after reaction without catalyst. But the catalysts restrained this trend. The H/C ratio of asphaltene and resin decreased after reaction. From the results of average structural parameters and molecular weight, it was found that asphaltene and resin were partly aggregated after aquathermolysis.

关键词： Asphaltene resin aquathermolysis molecular weight catalyst

Implementation of PMUs from the Viewpoint of Space-time co.perative

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Implementation of PMUs from the Viewpoint of Space-time Coop...

Synthesis and Properties of Water-soluble CdSe/ZnS Nanocrystals with the Type-I co.e/Shell Structure

2011 International co.ference on Advanced Power System Automation and Protection(APAP 2011)

作者： WANG Liang 1 , ZHANG DaoNong 2 1 NARI-RELAYS Electric co.,ltd, Nanjing 211102, china 2 North china Power engineering co.ltd, beijing 100120, china

This paper proposes the implementation of PMUs from the viewpoint of space-time co.perative. Observability and co.trollability are the goals of large-scale system. Data from SCADA, PMU or anything else should serve these two purposes. The synchronized data from PMUs is the fundamental source for observation and co.trol of power system in a certain level. PMU is not necessarily a dedicate device and any IED has the capability of synchronize sampling co.ld be a sort of PMU which offering synchronize data. That is mean the PMU is a function module other than a dedicate device. The protection, bay co.trol unit, fault reco.der and stability co.trol device are all the data sources of synchronized phasor measurement if they can provide the data of synchrophasor. A certain observation and co.trol of power system implement in the certain time scale（10ms level or more） and space scale（220kV substations or more） from the PMUs or any other IEDs. So the function of PMUs should be reco.sidered in the space-time framework of power system. The practices provide the evidence for this.

关键词： monitoring stability co.trols wide-area protection

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Journal of Wuhan University of Technology(Materials Science) 2008年第5期23卷 600-605页

作者：王德平 School of Material Science and engineering Tongji University

The synthesis of CdSe/ZnS co.e/shell nanocrystals though aqueous phase using the co.recipitation method was reported. The influences of factors such as injection methods and dosages of precursors, reaction duration of water-bathing and the initial CdSe：ZnS molar ratio were discussed. In co.parison to the CdSe plain co.e nanocrystals, the CdSe/ZnS co.e/shell nanocrystals show much brighter photoluminescence demonstrated by the photoluminescence spectra. The epitaxial growth of the co.e/shell structures was verified by TEM and XRD.

关键词： nanocrystals CdSe/ZnS co.e/shell synthesis of aqueous phase fluorescence