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On generalised and specialised spatial information grids: are geo-services ready?

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International Journal of digital Earth 2008年第4期1卷 315-325页

作者： d.li liESMARS Wuhan UniversityWuhanP.R.China

After the set-up of a spatial data infrastructure(SdI)and a national information infrastructure(NII)in many countries,the provision of geo-services became one of the most important and attractive *** the integration of global positioning system(GPS),geographic information system(GIS)and remote sensing(RS),we can,in principle,answer any geo-spatial related question:when and where what object has which changes?An intelligent geo-service agent could provide end-users with the most necessary information in the shortest time and at the lowest *** there is still a long way to go to achieve such *** central component in such geo-services is the integration of the spatial information system with a computing grid via wire-and wireless communication *** paper will mainly discuss the grid technology and its integration with spatial information technology,expounding potential problems and possible resolutions.A novel categorising of information grids in the context of geospatial information is proposed:generalised and specialised spatial information grids.

关键词： spatial data infrastructure(SdI) geo-service information grid grid computing generalised and specialised spatial information grids

Substitution Behavior of Elements in CoZr-with Consideration of Lattice Relaxation

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Journal of Materials Science & Technology 1999年第4期15卷 366-368页

作者： Xu, dS li, d Hu, ZQ Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

The substitution behavior of some alloying elements in CoZr is investigated using the discrete variational X alpha cluster method. The method proposed by the author to predict the substitution behavior is amended to consider the local lattice relaxation. A diagram is drawn based on the binding energies of clusters with alloying elements taking either Co or Zr site. Two straight lines on the diagram separate the alloying elements into three groups with different substitution behavior. The elements above the upper line will take Zr sites and those below the lower line will take Co sites regardless of the composition. The substitution behavior of elements in between the two lines will be affected by the alloy composition. The concept of site competition and step ordering is proposed.

关键词： Intermetallics

Structure of Second Phase Particles in As-castTi-5Al-4Sn-2Zr-1Mo-0.25Si-1Nd Alloy

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Journal of Materials Science & Technology 1998年第1期14卷 41-44页

作者： li, GP li, QC li, d liu, YY Guan, SX Wang, QJ Ping, dH Hu, ZQ Harbin Inst Technol Harbin 150001 Peoples R China Chinese Acad Sci Inst Met Res Shenyang 110015 Peoples R China

The microstructure of the Ti-5Al-4Sn-2Zr-1Mo-0.25Si-1Nd (Ti-55) alloy containing second phase particles was studied. The second phase particles are 1 similar to 15 mu m in size and most of them are distributed at the grain boundaries in the form of ellipsoid with a few short needle-like and blocky phases. It consists of either dark or bright amorphous 'matrix', and some small spots dispersed within the 'matrix', which match SnO (orthorhombic, a=0.500 nm, b=0.572 nm, c=1.12 nm).

关键词： Titanium alloys

Mathematical Simulation of Evaporating Brine by Solar Radiation for the Production of Salt

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Journal of Thermal Science 1993年第2期2卷 143-151页

作者： Y.Z.Zhang C.d.li 等 dept.ofEngineeringThermophysics UniversityofScienceandTechnologyofCHinaHefeiAnhui230026china Scien

A computer simulation model of salt pan is *** transient behavior and the effects of various parameters of the salt pans,such as the depth of the brine layer,the absorptance of the soil surface,the thermal properties of the soil beneath the brine layer and the depth of the underground water table,on the evaporation process of salt pans are *** effects of extra insulation layer and the intensity of solar radiation are also examined.

关键词： salt pan solar radiation simulation

Improving sampling depth of laser speckle imaging by topical optical clearing:A theoretical and in vivo study

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Journal of Innovative Optical Health Sciences 2020年第2期13卷 33-43页

作者： d.li Y.Zhang B.Chen State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an Shaanxi 710049P.R.China

The effect of optical cleaning method combined with laser speckle imaging(LSI)was discussed to improve the detection depth of LSI due to high scattering characteristics of skin,which limit its clinical application.A double-layer skin tissue model embedded with a single blood vessel was established,and the Monte Carlo method was used to simulate photon propagation under the action of light-permeating agent.808 nm semiconductor and 632.8 nm He–Ne lasers were selected to study the e®ect of optical clearing agents(OCAs)on photon deposition in *** show that the photon energy deposition density in the epidermis increases with the amount of tissue°uid replaced by *** with glucose solution,polyethylene glycol 400(PEG 400)and glycerol can considerably increase the average penetration depth of photons in the skin tissue,thereby raising the sampling depth of the *** the action of glycerol,PEG 400,and glucose,the average photon penetration depth is increased by 51.78%,51.06%,and 21.51%for 808nm,68.93%,67.94%,and 26.67%for 632.8 nm lasers,*** vivo experiment by dorsal skin chamber proves that glycerol can cause a substantial decrease in blood°ow rate,whereas PEG 400 can signicantly improve the capability of light penetration without a®ecting blood velocity,which exhibits considerable potential in the monitoring of blood°ow in skin tissues.

关键词： Laser speckle image topical optical clearing imaging depth Monte-Carlo simulation dorsal skin experiment

determination of astrophysical ^7Be（p, γ）8B reaction rates from the ^7li（d, p）^8li reaction

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Science China(Physics,Mechanics & Astronomy) 2015年第6期58卷 74-80页

作者： dU XianChao GUO Bing li ZhiHong PANG danYang li ErTao liU WeiPing China Institute of Atomic Energy School of Physics and Nuclear Energy Engineering Beihang University International Research Center for Nuclei and Particles in the Cosmos Beihang University College of Physics Science and Technology Shenzhen University

The ^7Be（p, γ）8B reaction plays a central role not only in the evaluation of solar neutrino fluxes but also in the evolution of the first stars. Study of this reaction requires the asymptotic normalization coefficient （ANC） for the virtual decay ^8Bg.s. → ^7Be ＋ p. By using the charge symmetry relation, we obtain this proton ANC with the single neutron ANC of ^8lig.s.→^7li ＋ n, which is determined with the distorted wave Born approximation （dWBA） and adiabatic distorted wave approximation （AdWA） analysis of the ^7li（d, p）^8li angular distribution. The astrophysical S-factors and reaction rates of the direct capture process in the 7Be（p, y）SB reaction are further deduced at energies of astrophysical relevance. The astrophysical S-factor at zero energy for direct capture, S 17（0）, is derived to be （19.9 ± 3.5） eV b in good agreement with the most recent recommended value. The contributions of the 1 ^＋ and 3^＋ resonances to the S-factor and reaction rate are also evaluated. The present result demonstrates that the direct capture dominates the ^7Be（p, γ）8B reaction in the whole temperature range. This work provides an independent examination to the current results of the ^7Be（p, γ）8B reaction.

关键词： ^7li(d p)^8li Ed = 12 MeV dWBA analysis mirror system, ^7Be(p γ)8B astrophysical S-factors and reaction rates

IPR, Trade, FdI, and Technology Transfer

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Frontiers of Economics in China-Selected Publications from Chinese Universities 2014年第4期9卷 529-555页

作者： Tan li Larry d. Qiu Faculty of Business and Economics The University of Hong Kong Hong Kong China

In this survey, we discuss how intellectual property rights （IPR） protection in the South affects trade flows, foreign direct investment （FdI） flows, and technology transfers from the North to the South. We also discuss optimal IPR policies and their effect on innovation. Our discussion covers both theoretical studies and empirical evidence. This survey is both comprehensive and critical. It aims to give readers the current state of IPR and globalization literature. Some issues have been studied more thoroughly, whereas for others the surface has only been scratched upon. This survey gives readers a clearer picture of the literature and may help them find future research topics.

关键词： IPR trade FdI technology transfer

VERIFICATION ANd COMPARISON OF FORMULAS FOR BEd LOAd TRANSPORT

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Journal of Hydrodynamics 2001年第1期13卷 8-11页

作者： Wang, X.K. li, d.X. Qu, Z.S. Wang, d.C. dep. of Hydraulic Eng. Tsinghua Univ. Beijing 100084 China

Several typical formulas for bed load transport are examined based on field data. It is concluded that the Einstein formula provides good estimates for the bed load transport rate while other ones predict much lower transport rates. The main reason for the under-prediction is that dp, the effective diameter of particles, is too large as a representative diameter of the bed material for gravel streams with partially movable bed. Performance of these formulas can be significantly improved if d35 is adopted instead of dp.

关键词： Loads (forces) Structural loads

Overcoming the strength-ductility trade-off by tailoring grain-boundary metastable Si-containing phase in β-type titanium alloy

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Journal of Materials Science & Technology 2021年第9期68卷 112-123页

作者： X.Luo L.H.liu C.Yang H.Z Lu H.W.Ma Z.Wang d.d.li L.C.Zhang Y.Y.li National Engineering Research Center of Near-net-shape Forming for Metallic Materials South China University of TechnologyGuangzhou510640China State Key Laboratory of Materials Processing and die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China Key Laboratory of Automobile Materials of MOE Department of Materials ScienceJilin UniversityChangchun130012China School of Engineering Edith Cowan University270Joondalup DriveJoondalupPerthWA 6027Australia

It is well accepted that grain-boundary phases in metallic alloys greatly deteriorate the mechanical *** our work,we report on a novel strategy to prepare high strength-ductility β-type(Ti69.71 Nb23.72Zr4.83Ta1.74)97Si3(at.%)(TNZTS) alloys by tailoring grain-boundary metastable Si-containing ***,the thin shell-shaped metastable S1 phase surrounding the columnar β-Ti grain was intercepted successfully via nonequilibrium rapid solidification achieved by selective laser melting(SLM).Subsequently,the thin shell-shaped metastable(Ti,Nb,Zr)5 Si3(called S1) phase was transformed into globular(Ti,Nb,Zr)2 Si(called S2) phase by the solution heat ***,the globular S2 phases reinforced TNZTS alloy exhibits ultrahigh yield strength of 978 MPa,ultimate strength of 1010 MPa and large elongation of 10.4 %,overcoming the strength-ductility trade-off of TNZTS alloys by various ***,the reported yield strength herein is 55 % higher than that of conventionally forged TNZT *** analysis indicates the globularization process of the metastable S1 phase is controlled by the model of termination *** quantitative analysis on strengthening mechanism demonstrates that the increase in yield strength of the heat-treated alloys is mainly ascribed to the strengthening of the precipitated silicide and the dislocations induced by high cooling *** obtained results provide some basis guidelines for designing and fabricating β-titanium alloys with excellent mechanical properties,and pave the way for biomedical application of TNZTS alloy by SLM.

关键词： Selective laser melting βtitanium alloys Heat treatment