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Integral equation of relationship on the apparent conductivity and true conductivity in induction logging

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Science China Earth Sciences 2014年第5期57卷 1972-1978页

作者： li jianhao China Petroleum Logging Co.Ltd

This paper investigates the relation between the induced electromotive force measured by induction logging tool and the apparent conductivity, and the relation between the apparent conductivity and the formation true conductivity. Assuming the conductivity in Green's function to be the function of the field point coordinate, the apparent conductivity expression of electric-field intensity is derived using Green's formula, and the integral equation has been established representing the relationship of the apparent conductivity with the true conductivity under this condition. The integral equation is analyzed and then leads to the conclusion that the equivalent conductivity is the apparent conductivity and the values of the apparent conductivity function contain the true conductivity, and the method derived the true conductivity from the apparent conductivity around the well axis is put forward. The validity of the approach given in this paper is verified through numerical calculation. On the basis of above means, the transmitter coil produces an electric-field distribution in formation at every point where the induction logging tool moves along a wellbore, and a number of the receiving coils obtain an apparent conductivity distribution; this is what induction electric-field logging is.

关键词： electric-field intensity induction logging formation apparent conductivity true conductivity integral equation

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Research on Service life Prediction Model of Concrete Structure of Sea-crossing Bridge

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武汉理工大学学报 2010年第17期32卷 141-146页

作者： WANG C j ZhANG G Z liU K X TU L Q li j h QIN M Q Zhejiang Province Zhoushan Island linking Construction Commanding Department Zhejiang 316032China Wuhan harbor Engineering Design & Research Institute Co. Ltd Wuhan 430071China Key Lab of Large-span Bridge Construction Technology Ministry of CommunicationWuhan 430071China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

According to the chloride corrosion environment,service life prediction model of concrete structure of sea-crossing bridge was built using modified Fick's second law and the whole probability calculation method,which was suitable for China. Furthermore,a visual service life prediction program of concrete structure was developed by optimized Monte Carlo method. Meanwhile,life 365 program was compared,indicating reliability of the prediction program. Finally,the validity of prediction model was verified in jinTang Bridge of Zhoushan Island Mainland linkage Project.

关键词： sea-crossing bridge concrete structure service life prediction model verify

The absolute paleoposition of the North China Block during the Middle Ordovician

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Science China Earth Sciences 2016年第1期59卷 573-582页

作者： WANG hong hao li jiang hai ZhANG hua Tian XU li li Wei Bo Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space SciencesPeking University

Present-day hot spots and Phanerozoic large igneous provinces(liPs) and kimberlites mainly occur at the edges of the projections of Large Low Shear Wave Velocity Provinces(LLSVPs) on the earth's surface. If a plate contains accurately dated liPs or kimberlites, it is possible to obtain the absolute paleoposition of the plate from the liP/kimberlite and paleomagnetic data. The presence of Middle Ordovician kimberlites in the North China Block provides an opportunity to determine the absolute paleoposition of the block during the Middle Ordovician. In addition to paleobiogeographical information and the results of previous work on global plate reconstruction for the Ordovician Period, we selected published paleomagnetic data for the North China Block during the Middle Ordovician and determined the most reasonable absolute paleoposition of the North China Block during the Middle Ordovician: paleolatitude of approximately 16.6°S to 19.1°S and paleolongitude of approximately 10°W. The block was located between the Siberian Plate and Gondwana, close to the Siberian Plate. During the Cambrian and Ordovician periods, the North China Block may have moved toward the Siberian Plate and away from the Australian Plate.

关键词： North China Block Middle Ordovician Absolute paleoposition Plume Generation Zone

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The Zunhua-Zanhuang Ophiolitic Mélange: Traces of an Archean Suture in the North China Craton

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Acta Geologica Sinica(English Edition) 2015年第A02期89卷 37-38页

作者： KUSKY T.M li j.h PLOAT A WANG junpeng DENG hao WANG Lu Center for Global Tectonics China University of Geosciences Wuhan 430074 China Department of Geology Peking University China Department of Earth and Environmental Sciences University of Windsor Ontario Canada

Sutures mark places once widely separated defined on the basis differences in the where oceans have closed and two terranes have collided. Sutures are of geological relationships, and geologic, structural, magmatic,

关键词： RESEARCh Suture zones (Structural geology) Orogenic belts Structural geology Ophiolites Melanges (Petrology)

A gravity-spatial entropy model for the measurement of urban sprawl

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Science China Earth Sciences 2016年第2期59卷 207-213页

作者： li ji hong QIU Rong Xu XIONG Le XU jia Dong Forestry College Northeast Forestry University Geography Department University of Lethbridge Tourism Department Fudan University

Since the mid-twentieth century, most cities worldwide have undergone a rapid expansion in urban land use. Along with the expansion, several problems, such as excessive loss of prime agricultural land and increasing traffic congestion have arisen. Thus, understanding and measurements of the expansion scale and its speed are crucial to planners and officials during urban planning and management processes. To measure such geographic phenomena, Shannon first devised entropy theory, and then Batty developed it into spatial entropy. The recently developed spatial entropy model, which was used to measure urban sprawl, introduced area to represent spatial asymmetry. however, most models did not consider spatial discretization, particularly the impact of distance. This study attempted to construct an integrated gravity-spatial entropy model to delineate distance and spatial diffusion impacts on population distribution. Then, we tested the model using Shanghai's temporal land use and community statistical data. Application results for the new gravity-spatial model show that it is a useful tool for identifying spatial and temporal variations of urban sprawl.

关键词： Entropy Spatial entropy Gravity model Urban sprawl

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An Agent-Based Distributed Manufacturing System

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武汉理工大学学报 2006年第S1期28卷 48-54页

作者： j.Y.h.Fuh A.Y.C.Nee Department of Mechanical Enginering National Universit of Singapore9 Engineering Drive 1Singapore 117576

Agent theories have shown their promising capability in solving distributed complex system ever since its development. In this paper,one multi-agent based distributed product design and manufacturing planning system is presented. The objective of the research is to develop a distributed collaborative design environment for supporting cooperation among the existing engineering functions. In the system,the functional agents for design,manufacturability evaluation,process planning and scheduling are efficiently integrated with a facilitator agent. This paper firstly gives an introduction to the system structure,and the definitions for each executive agent are then described and a prototype of the proposed is also included at the end part.

关键词： multi-agent systems distributed manufacturing processing planning and scheduling

城市矿山开发及其资源调控:特征、可持续性和开发机理

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中国科学：地球科学 2018年第3期48卷 288-298页

作者：曾现来李金惠清华大学环境学院北京100084

城市矿山开发及其资源调控不仅属于环境科学及地球科学关注的热点,也是影响当前中国可持续发展和生态文明建设的关键.本文总结过去对于城市矿山及城市矿产的科学认识,全面梳理城市矿山开发及其资源调控中的基础问题和活动实践,并指出未... 详细信息

城市矿山开发及其资源调控不仅属于环境科学及地球科学关注的热点,也是影响当前中国可持续发展和生态文明建设的关键.本文总结过去对于城市矿山及城市矿产的科学认识,全面梳理城市矿山开发及其资源调控中的基础问题和活动实践,并指出未来城市矿山资源开发的主要科学问题.凝练的主要认识包括:城市矿产是人为活动条件下产生的,具有有序的物理结构、固定形状等鲜明产品特征的再生资源;城市矿产的资源特性不仅决定于它的质量,也取决于其中元素成分的数量;循环化学三条基本定律基本形成,分别指出了物质循环的必要性、方向性和目标性.未来应该研究的核心科学问题包括,金属资源从自然地学循环到人类圈循环的转换特征和驱动机制是什么;在人类圈循环中,资源的闭路循环关键节点和瓶颈在哪里;如何改善加快城市矿产的逆向物流和调控.

关键词：城市矿山城市矿产资源转化资源开发可持续性循环经济

Physical simulation and application of a new TEM configuration

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Physical simulation and application of a new TEM configurati...

Quasi-classical trajectory study of h+lih（v=0,1,2,j=0）→li+h2 reaction on a new global potential energy surface

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： G.Q.Xue X.li·h.j.Quan S.jaggar N.N.Zhou Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences College of Geology Engineering and Geomatics Chang'an University

In some applications,especially for tunnel surveys and ancient tomb investigations,the scale of survey location is so small that it is impossible to lay a large enough transmitter loop for detection.A small-scale and high-power Transient Electromagnetic(TEM) transmitter configuration must be adapted to detect longer distance or greater *** the TEM surveying configuration may facilitate improving signal penetration and precision of TEM *** on physical simulation,a newly designed special-loop-source TEM survey configuration has been introduced,which employs four square apertures within a single large transmitter loop to excite stronger *** primary and secondary fields have been measured using both the new special-loop system and standard normal single loop TEM configuration for different receiver-transmitter separations and for different target *** response curves were compared, revealing that the primary field intensity and the secondary field response were improved by the special-loop transmitter system as compared to the standard *** new special-loop configuration can be used for tunnel TEM prediction and other TEM investigations.A case study was conducted on tunnel forecasting in hubei Province,China. This terra TEM survey showed that it is an effective and successful method for exploring and predicting challenging geological structures ahead of a tunnel wall during excavation.

关键词： Transient electromagnetic Loop configuration Small loop Model tests

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Chinese Physics B 2019年第8期28卷 105-111页

作者： Yu-liang Wang De-Zhi Su Cun-hai liu hui li School of Basic Sciences for Aviation Naval Aviation University

Quasi-classical trajectory(QCT)calculations are reported for the h+lih(v=0-2,j=0)→li+h2 reaction on a new ground electronic state global potential energy surface(PES)of the lih2 *** probability and integral cross sections(ICSs)are calculated for collision energies in the range of 0 eV-0.5 *** agreement is found in the comparison between present results and previous available theoretical *** carried out statistical analyses with all the trajectories and found two main distinct reaction mechanisms in the collision process,in which the stripping mechanism(i.e.,without roaming process)is dominated over the collision energy *** polarization dependent differential cross sections(PDDCSs)indicate that forward scattering dominates the reaction due to the dominated ***,the reactant vibration leads to a reduction of the reactivity because of the barrierless and attractive features of PES and mass combination of the system.

关键词： quasi-classical trajectory h+lih vibrational excitation reaction dynamics