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International Journal of digital Earth 2016年第12期9卷 1185-1205页

作者： N.Sang C.Gold d.Miller department of Landscape Architecture Planning and Management Swedish University of Agricultural ScienceAlnarpSweden AnserGIS AB LundSweden department of Computing and Mathematics University of South WalesPontypriddUK The James Hutton Institute AberdeenUK

The effort to develop a digital Earth has made dramatic progress in terms of visualisation and visual data integration for use-cases which demand semantically rich *** provide this analysis and ensure legitimate representations of the spatial data from which visualisation are derived,it is necessary to provide more comprehensive analytical capabilities of the *** of aesthetic valuation of landscape require a richer analytical response than simply‘whether and possibly how much of’an object or area of land can be *** requires interrogation of the scene as it appears and to distinguish between transient visual effects and those locally invariant to view point *** paper explores a data structure to support scene *** such,it first reviews the existing techniques from the fields of GIS and computer graphics as to their potential and limitations in providing a qualitatively more nuanced visual *** then introduces a new method of encoding visually apparent relationships into terrain models.A prototype implementation is presented based on the Quad-Edge Triangular Irregular Network,though it is believed that raster or vector implementation would be *** developed primarily with landscape analysis in mind,the method could have wider applicability.

关键词： Visibility analysis landscape topology viewshed

Optimal thermoelectric figure of merit of Si/Ge core-shell nanowires

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Nano research 2015年第8期8卷 2611-2619页

作者： Kaike Yang Andres Cantarero Angel rubio roberto d'Agosta Nano-Bio Spectroscopy Group and ETSF Scientific development Center Departamento de Fisica de Materiales Universidad del Pais Vasco UPV/EHU San Sebastian 20018 Spain Instituto de Ciencia de Materiales Universidad de Valencia Valencia 46071 Spain Ikerbasque Basque foundation for Science Bilbao 48013 Spain

We investigate the thermoelectric energy conversion efficiency of Si and Ge nanowires, and in particular, that of Si/Ge core-shell nanowires. We show how the presence of a thin Ge shell on a Si core nanowire increases the overall figure of merit. We find the optimal thickness of the Ge shell to provide the largest figure of merit for the devices. We also consider Ge core/Si shell nanowires, and show that an optimal thickness of the Si shell does not exist, since the figure of merit is a monotonically decreasing function of the radius of the nanowire. Finally, we verify the empirical law relating the electron energy gap to the optimal working temperature that maximizes the efficiency of the device.

关键词： thermoelectric properties Seebeck coefficient silicon and germanium core-shell nanowires

Effect of Y content and equal channel angular pressing on the microstructure, texture and mechanical property of extruded Mg-Y alloys

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Journal of Magnesium and Alloys 2022年第1期10卷 210-224页

作者： W.Yang G.F.Quan B.Ji Y.F.Wan H.Zhou J.Zheng d.d.Yin Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengduSichuan 610031China Nano and Heterogeneous Materials Center School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringShenyang National Laboratory for Materials ScienceChongqing UniversityChongqing 400044China

The microstructure, texture and mechanical property evolution of the extruded Mg-x Y(x = 1, 5 wt.%) alloys during equal channel angular pressing(ECAP) were systematically investigated using an optical microscope, electron backscatter diffraction(EBSd) and uniaxial tensile test. The Mg-Y alloys exhibited a weakened basal texture before the ECAP, and the texture was further weakened with the max basal poles dispersed along ~45° between the extrusion direction and the transverse direction after the ECAP. The Mg-5 Y alloys always exhibited a finer grain size comparing to that of Mg-1 Y for the same ECAP process. With a proper ECAP process, both the strength and elongation of Mg-5 Y alloy could be improved simultaneously after the ECAP, i.e., the yield strength(273.9 ± 1.2 MPa), ultimate strength(306.4 ± 3.0 MPa),and elongation(23.9 ± 1.0%) were increased by 10%, 6%, and 72%, respectively, comparing to that before the ECAP. This was considered to be arose from the combined effects of grain refinement, significant improved microstructure homogeneity and solid solution *** addition, it was found that Mg-Y alloy with better comprehensive properties could be obtained by the decreasing-temperature ECAP processes. The yield strength-grain size relationship could be well described by the Hall-Petch relation for all the ECAPed Mg-Y alloys,which was consistent with that the texture changes did not significantly affect the average Schmid factors of basal, prismatic and pyramidal slips for both Mg-Y alloys.

关键词： Mg-rE alloy Equal channel angular pressing Texture Mechanical property

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

Variable retention harvesting in Great Lakes mixed-pine forests: emulating a natural model in managed ecosystems

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Ecological Processes 2019年第1期8卷 210-224页

作者： Brian J.Palik Anthony W.d’Amato USdA Forest Service Northern Research StationGrand RapidsMN 55744USA rubenstein School of Environment and Natural resources University of VermontBurlingtonVT 05095USA.

Variable retention harvesting(VrH)systems have gained wide use in many different forest types across the globe,but largely have been implemented in forests characterized by severe,infrequent disturbance *** has been less attention given to developing VrH approaches in forests that are characterized as having a mixed-severity disturbance regime that often results in only partial mortality of canopy trees in spatially heterogeneous *** example of such a forest type is red pine(Pinus resinosa Ait.)-dominated ecosystem of the western Great Lakes region of North *** purpose of this review is to provide a conceptual foundation for developing VrH approaches in red pine ecosystems that are based on a mixed-severity disturbance *** contention is that red pine forests managed following a natural model are more resilient to disturbances and external threats such as climate *** the red pine ecosystem,VrH application should reflect the often severe,but partial canopy removal from natural disturbance that is characteristic of this ecosystem and that results in more than trivial numbers of surviving overstory trees across a range of spatial configurations in regenerating *** live trees should span a range of diameters,but favor the larger end of the diameter distribution,as this reflects the likely pattern of survival after natural disturbance and is often a key structural element lacking from managed *** should be applied in ways that vary the spatial pattern of legacy trees in and among stands,but largely in ways that reflect the pattern of spatially patchy canopy structure,with large openings surrounded by a less disturbed matrix,as occurs with a natural disturbance *** trees and deadwood structures should reflect the composition of the pre-disturbance forest,including species in addition to dominant red ***,retained structures should be viewed as dynamic entities that grow,die,and decay and that need

关键词： red pine Mixed-severity Variable retention Natural disturbance

Equations of Propagation of Uncertainty on the ITS-90 in the Sub-ranges from 13.8033 K to 933.473 K

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Chinese Physics Letters 2005年第3期22卷 558-560页

作者：康志茹傅广生 K.d.Hill CollegeofPhysicsTechnology HebeiUniversityBaoding071002//HebeiProvincialInstituteofMetrologyShijiazhuang050051 CollegeofPhysicsTechnology HebeiUniversityBaoding071002 NationalresearchCouncilofCanada OttawaCanada

Based on implicit differentiation, we present the total differential of linear interpolation and the equation of propagation of uncertainty on the ITS-90 in any of the sub-ranges from 13.8033K to 933.473K. It is proven that the sensitivity coefficients of the linear interpolation are still linear combinations of the basis functions comprising the interpolation equation, only with different constants that can be presented in the determinant form. This solves the question to express the equation of propagation of uncertainty of a complex interpolation comprised of many different basic functions.

关键词： TS-90 Sub-ranges 13.8033K 933.473K

Potential for targeted therapy in prostate cancers with ErG abnormalities

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Asian Journal of Andrology 2011年第6期13卷 781-782页

作者： Sean r Williamson Liang Cheng department of Pathology Indiana University School of Medicine Indianapolis IN 46202 USA department of Urology Indiana University School of Medicine Indianapolis IN 46202 USA

Since the recent identification of recurrent gene fusions in prostate cancer betweenmembers of the ETS family of genes and transmembrane protease, serine 2 （TM PrSS2）, a tremendous amount of interest has developed in the pathways through which these fusions contribute to prostatic carcinogenesis, as well as their diaenostic utilitv.

关键词： identification recurrent gene fusions prostate cancer

Soret and dufour effects on mixed convection unsteady MHd boundary layer flow over stretching sheet in porous medium with chemically reactive species

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Applied Mathematics and Mechanics(English Edition) 2014年第7期35卷 849-862页

作者： A.NAYAK S.PANdA d.K.PHUKAN Silicon Institute of Technology Bhubaneswar 751024 India department of Mathematics National Institute of Technology Calicut 673601 India department of Mathematics Moran College Moranhat Assam 785670 India

This paper studies the thermal-diffusion and diffusion thermo-effects in the hydro-magnetic unsteady flow by a mixed convection boundary layer past an imperme- able vertical stretching sheet in a porous medium in the presence of chemical reaction. The velocity of t^he stretching surface, the surface temperature, and the concentration are assumed to vary linearly with the distance along the surface. The governing partial differential equations are transformed into self-similar unsteady equations using similarity transformations .and solved numerically by the runge-Kutta fourth order scheme in as- sociation with the shooting method for the whole transient domain from the initial state to the final steady state flow. Numerical results for the velocity, the temperature, the concentration, the skin friction, and the Nusselt and Sherwood numbers are shown graph- ically for various flow parameters. The results reveal that there is a smooth transition of flow from unsteady state to the final steady state. A special case of our results is in good agreement with an earlier published work.

关键词： heat and mass transfer boundary layer flow porous media magnetic field,Soret number dufour number

Analysis of global and local stress changes in a longwall gateroad

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International Journal of Mining Science and Technology 2018年第1期28卷 127-135页

作者： I.B.Tulu G.S.Esterhuizen d.Gearhart T.M.Klemetti K.M.Mohamed d.W.H.Su department of Mining Engineering West Virginia University NIOSH Pittsburgh Mining Research Division

A numerical-model-based approach was recently developed for estimating the changes in both the horizontal and vertical loading conditions induced by an approaching longwall *** this approach, a systematic procedure is used to estimate the model's *** along the bedding planes is modeled with ubiquitous joint elements and interface *** is modeled with a newly developed coal mass *** response of the gob is calibrated with back analysis of subsidence data and the results of previously published laboratory tests on rock *** model results were verified with the subsidence and stress data recently collected from a longwall mine in the eastern United States.

关键词： Longwall mining Gateroad design Flac3d Horizontal angle Gob loading Hollow inclusion cells

Performance analysis of machine learning algorithms on automated sleep staging feature sets

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CAAI Transactions on Intelligence Technology 2021年第2期6卷 155-174页

作者： Santosh Satapathy d Loganathan Hari Kishan Kondaveeti ramaKrushna rath Puducherry Research Scholar of Computer Science and EngineeringPondicherry Engineering CollegePuducherryIndia Professor of Computer Science and Engineering Pondicherry Engineering CollegePuducherryPuducherryIndia Assistant Professor of Computer Science and Engineering VIT UniversityAmaravatiAndhra PradeshIndia research Scholar of Computer Science and Engineering Anna UniversityChennaiIndia

With the speeding up of social activities,rapid changes in lifestyles,and an increase in the pressure in professional fields,people are suffering from several types of sleep-related *** is a very tedious task for clinicians to monitor the entire sleep durations of the subjects and analyse the sleep staging in traditional and manual laboratory environmental *** the purpose of accurate diagnosis of different sleep disorders,we have considered the automated analysis of sleep epochs,which were collected from the subjects during sleep *** complete process of an automated approach of sleep stages5 classification is majorly executed through four steps:pre-processing the raw signals,feature extraction,feature selection,and *** this study,we have extracted 12 statistical properties from input *** proposed models are tested in three different combinations of features *** the first experiment,the feature set contained all the 12 *** second and third experiments were conducted with the nine and five best *** patient records come from the ISrUC-Sleep *** highest classification accuracy was achieved for sleep staging through combinations with the five feature *** the categories of the subjects,the reported accuracy results were found to exceed above 90%.As per the outcome from the proposed system the random forest classification techniques achieved best accuracy incomparable to that of the other two classifiers.

关键词： sleep staging diagnosis