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International Journal of Digital Earth 2020年第12期13卷 1672-1694页

作者： Petr Klápště Michal Fogl Vojtěch Barták Kateřina Gdulová Rudolf Urban Vítězslav Moudrý Department of Applied Geoinformatics and Spatial Planning Faculty of Environmental SciencesCzech University of Life Sciences PragueKamýcká129Praha-Suchdol16500Czech Republic Department of Special Geodesy Faculty of Civil EngineeringCzech Technical University in PraguePragueCzech Republic

Most ground filtering algorithms are primarily designed for airborne LiDAR point cloud processing and their successful use in identifying ground points from photogrammetric point clouds remains *** compared six ground filtering algorithms implemented in Metashape,ArcGIS,CloudCompare,LAStools,and *** used UAV photogrammetry-based(acquired under leaf-off conditions)and airborne LiDAR(leaf-on)point clouds of the same area to:(i)compare accuracy of generated DTMs;(ii)evaluate the effect of vegetation density and terrain slope on filtering accuracy;and(iii)assess which algorithm parameters have the greatest effect on the filtering *** results show that the performance of filtering algorithms was affected by the point cloud type,terrain slope and vegetation *** results were generally better for LiDAR(RMSE 0.13–0.19 m)than for photogrammetric(RMSE 0.19–0.23 m)point *** behavior in varying vegetation and terrain conditions was consistent for LiDAR point ***,when applied on photogrammetric point clouds,the algorithms’behavior was inconsistent,especially in areas of steep slope(except for the Progressive Triangulated Irregular Network in LAStools).Parameters related to the selection of the initial minimum elevation ground points were the most influential in all algorithms and point clouds.

关键词： DTM filtering LiDAR point cloud spoil heap UAV

Research on a Dispersed Networked CAD/CAM System of Motorcycle

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厦门大学学报（自然科学版） 2002年第S1期41卷 167-168页

作者： WANG Xian-kun (Dept. of Mechanical Engineering, Fuzhou University, Fuzhou 350002, ch ina)

In order to improve competitive ability of market, mo torcycle enterprises, special the small and middle sized ones must use IT to org anize social resource and adopt effective production mode, namely the dispersed networked design and manufacturing (DNDM), which was put forward and proved to b e one of vitality production modes in recent years. In responding to the new pro duction mode of VMCE, a dispersed networked CAD/CAM system (DNCADMS) of motorcyc le products should be developed. The objective of this paper is to investigate a new design and manufacturing mode and technical environment of motorcycle produ ction based on the concept of the DNDM for the small and meddle sized motorcycle enterprises. Because there are various CAx software systems, including differen t kinds of isolated CD, CAD, CAE, CAPP, CAM, PDM, and so on, are used at differe nt stages of the life period of motorcycle products under heterogeneous environm ents, to build a DNCADMS of motorcycle with high performance, some key issues, n amely the architecture of the DNCADMS, the integration of the isolated CAx softw are systems (CAxs), the data communication and exchange between these isolated s ystems and the data share problem under the dispersed heterogeneous database env ironment, should be solved well. For this, the idea we propose is the combinatio n of Web, CORBA, STEP and Java, which provides an effective mechanism to support the integration of isolated CAxs, and support communication and interoperabilit y among CAx systems. Each isolated CAx has been encapsulated respectively by a c ontainer, which is implemented by the ORBs and the IDL of the COBRA technology s tandard, and managed by the application index server. Each container is connecte d with the others by a local network or intranet/Extranet/internet and communica tes through network. For exchanging design and manufacturing information and kno wledge via a local network or the Internet, a commmerical product data translato r has

关键词： dispersed networked CAD/CAM PDM motorcycle We b CORBA

Dynamics of electrodeposition of tetraethylthioram disulphide(TETD) on pyrite surface

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Journal of Central South University 2001年第3期13卷 164-168页

作者： QIN Wen-qing,QIU Guan-zhou,hU Yue-hua,XU Jing (Department of Mineral Enginering, Central South University, changsha 410083, ch ina) 1. Department of Mineral Enginering Central South University 410083 Changsha China

The electrode process of pyrite in diethyldithiocarbamate (DDTC) solution ph 11.4 was investigated by using cyclic voltammetry, potentiost atic and chronopotentiometry. Tetraethylthioram disulphide(TETD) was electrodepo sited on pyrite electrode surface as the electrode potential is higher than 0.2 V. The relationship of the current density caused by diffusion and reaction time can be ascertained as i =1/(9.08×10 -5 +4.77×10 -3 t 0.5 ) , and the diffusion coefficient of DDTC on pyrite surface is about 3.72×10 - 6 cm 2/s. At ph 11.4, the thickness of TETD adsorbed on pyr ite surface is about 1.63 molecule layer. The electrochemical dynamics equation of the reduction of TETD on pyrite surface is given as η =0.116-0.064log[1- ( t/τ ) 0.5 ]. The kinetic parameters were determined as follows: the ex change current density ( i 0) is 3.08 μA/cm 2; the transmission coeffi cient( α ) is 0.462.

关键词： electrode process pyrite electrochemistry of flotation

Dimensionality-driven metal to Mott insulator transition in two-dimensional 1T-TaSe2

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National Science Review 2024年第3期11卷 108-118页

作者： Ning Tian Zhe huang Bo Gyu Jang Shuaifei Guo Ya-Jun Yan Jingjing Gao Yijun Yu Jinwoong hwang Cenyao Tang Meixiao Wang Xuan Luo Yu Ping Sun Zhongkai Liu Dong-Lai Feng Xianhui chen Sung-Kwan Mo Minjae Kim young-Woo Son Dawei Shen Wei Ruan Yuanbo Zhang State Key Laboratory of Surface Physics New Cornerstone Science Laboratory and Department of PhysicsFudan University Shanghai Qi Zhi Institute Shanghai Research Center for Quantum Sciences Institute for Nanoelectronic Devices and Quantum Computing Fudan University Zhangjiang Fudan International Innovation Center Fudan University State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology(SIMIT)Chinese Academy of Sciences School of Physical Science and Technology ShanghaiTech University Korea Institute for Advanced Study School of Emerging Technology and Department of Physics University of Science and Technology of China Advanced Light Source Lawrence Berkeley National Laboratory ShanghaiTech Laboratory for Topological Physics Key Laboratory of Materials Physics Institute of Solid State Physics Hefei Institutes of Physical ScienceChinese Academy of Sciences high Magnetic Field Laboratory Hefei Institutes of Physical Science Chinese Academy of Sciences Collaborative Innovation Centre of Advanced Microstructures Nanjing University Department of Physics University of Science and Technology of China and Key Laboratory of Strongly Coupled Quantum Matter Physics Chinese Academy of Sciences National Synchrotron Radiation Laboratory University of Science and Technology of China

Two-dimensional materials represent a major frontier for research into exotic many-body quantum phenomena. In the extreme two-dimensional limit, electron-electron interaction often dominates over other electronic energy scales, leading to strongly correlated effects such as quantum spin liquid and unconventional *** dominance is conventionally attributed to the lack of electron screening in the third dimension. here, we discover an intriguing metal to Mott insulator transition in 1T-TaSe2that defies conventional wisdom. Specifically, we find that dimensionality crossover, instead of reduced screening, drives the transition in atomically thin 1T-TaSe2. A dispersive band crossing the Fermi level is found to be responsible for the bulk metallicity in the material. Reducing the dimensionality,however, effectively quenches the kinetic energy of these initially itinerant electrons, and drives the material into a Mott insulating *** dimensionality-driven metal to Mott insulator transition resolves the long-standing dichotomy between metallic bulk and insulating surface of 1T-TaSe2. Our work further reveals a new pathway for modulating two-dimensional materials that enables exploring strongly correlated systems across uncharted parameter space.

关键词： two-dimensional materials 1T-TaSe2 dimensionality crossover metal to Mott insulator transition

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数字游民:追求工作和休闲的全面自由

工会理论研究 2024年第2期 71-79页

作者：伊娜·赖兴伯格姚建华徐偲骕(编译) 新西兰惠灵顿维多利亚大学旅游管理学系复旦大学新闻学院复旦大学马克思主义新闻观教学与研究基地上海大学新闻传播学院上海大学中国当代文化研究中心

数字游民群体主要由年轻的专业人士组成,他们从事线上工作并将旅行融入日常生活。这种生活方式打破了传统的居住和工作地点的限制,工作、休闲和旅行之间的界限也随之变得模糊。本文旨在界定“数字游民”这一概念,探讨该群体选择数字游... 详细信息

数字游民群体主要由年轻的专业人士组成,他们从事线上工作并将旅行融入日常生活。这种生活方式打破了传统的居住和工作地点的限制,工作、休闲和旅行之间的界限也随之变得模糊。本文旨在界定“数字游民”这一概念,探讨该群体选择数字游牧的动机,以及如何将这些动机付诸实践。数字游民追求一种以全面自由为特征的整体性生活方式,力图实现职业自由、空间自由和个人自由。在理想状态下,他们将工作看作是一种源自内部动机的活动,它并不比休闲低等,更不仅仅是一种个人不得不履行的责任。同时,尽管休闲(包括旅行)是这种生活方式给人以积极体验的重要来源,它也带来了不少挑战,因此本质上还是一种不同形态的工作。

关键词：数字游民整体性生活方式工作休闲自由

Research on a New Type of Diamond Saw Plate

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厦门大学学报（自然科学版） 2002年第S1期41卷 294-295页

作者： ShI Xiao-liang, DUAN Long-chen, TANG Feng-lin, YANG Kai- hua (Engineering Faculty, china University of Geosciences, Wuhan 430074, ch ina)

With the developing of stone material, diamond saw pl ate is used widely, and in order to increase cutting efficiency and life-span o f diamond saw plate, there are a lot of research jobs of segment for diamond saw plate. Layered segment for diamond saw plate is to divide single segment into s everal cutting tools by its structure, then increases rock-cutting faces. For i mpregnated man-made diamond saw plate, the bonding strength of diamonds with ma trix material has great effect on its life and service. Diamond is a kind of non metal and there is such high interface energy between diamond and common metals or alloys that diamond surface can’t be soaked by low melt-point metal or allo y. Diamonds are hold in metal matrix of working layer only mechanically, rather than bonded chemically, so the usage rate of diamonds in working layer is very l ow. Weakly impregnated method refers to covering diamonds with a thin layer of tu ngsten carbide mechanically by physical method, and chemical plating membrane re fers to coating a layer of carbide, which can react with the carbon atoms on the surface of diamond by chemical method and be soaked by matrix metal. In this pa per it analyses working mechanism and sintering process of layered segment of di amond saw plate by means of resistor hot-pressing sintering, it points out shor tages of layered structure, and raises using weakly impregnated layer instead of pure matrix layer, then overcomes the pure matrix layer slipping by pulling out diamonds earlier to improve cutting efficiency of saw plate, in the same time u ses diamond grains of chemical plating membrane proposed then preventing the hea t-hurting to diamond grains in working layer during the process of welding and sintering and improving the bonding strength of diamond with matrix, then improv ing life-span and aging of diamond saw. The theory of the design of mixed holding of diamonds by matrix of saw plate assures that chemical plating diamonds in working layer cut

关键词： diamond saw plate layered segment weakly impre gnated plating membrane slipping

Biased dispersal of Metrioptera bicolor, a wing dimorphic bush-cricket

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Insect Science 2018年第2期25卷 297-308页

作者： ina Monika Margret heidinge Silke hein heike Feldhaar hans-Joachim Poethke Field Station Fabrikschleichach University of W（Jrzburg Rauhenebrach Germany W~sseri 8 CH-8816 Hirzel Switzerland Department of Animal Ecology I University of Bayreuth Bayreuth Germany Bavarian State Institute for Viticulture and horti- culture Bee Research Center An der Steige 15 97206 VeitshSchheim Germany

In the highly fragmented landscape of central Europe, dispersal is of particular importance as it determines the long-term survival of animal populations. Dispersal not only secures the recolonization of patches where populations went extinct, it may also rescue small populations and thus prevent local extinction events. As dispersal involves different individual fitness costs, the decision to disperse should not be random but context- dependent and often will be biased toward a certain group of individuals （e.g., sex- and wing morph-biased dispersal）. Although biased dispersal has far-reaching consequences for animal populations, immediate studies of sex- and wing morph-biased dispersal in orthopterans are very rare. here, we used a combined approach of morphological and genetic analyses to investigate biased dispersal of Metrioptera bicolor, a wing dimorphic bush-cricket. Our results clearly show wing morph-biased dispersal for both sexes of M. bicolor. In addition, we found sex-biased dispersal for macropterous individuals, but not for micropters. Both, morphological and genetic data, favor macropterous males as dispersal unit of this bush-cricket species. To get an idea of the flight ability ofM. bicolor, we compared our morphological data with that of Locusta migratoria and Schistocerca gregaria, which are very good flyers. Based on our morphological data, we suggest a good flight ability for macropters of M. bicolor, although flying individuals of this species are seldom observed.

关键词： aspect ratio dispersal traits flight muscle ratio Metrioptera bicolor sex-biased dispersal wing load wing morph-biased dispersal

Development of open-porosity magnesium foam produced by investment casting

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Journal of Magnesium and Alloys 2022年第7期10卷 1941-1956页

作者： honorata Kapłon Carsten Blawert Jacek ch˛ecmanowski Krzysztof Naplocha Faculty of Mechanical Engineering Wrocław University of Science and TechnologyUl.Smoluchowskiego 25Wrocław 50-370Poland Institute of Surface Science Helmholtz-Zentrum GeesthachtMax-Planck-Straβe 1Geesthacht21502Germany Faculty of chemistry Wrocław University of Science and TechnologyWybrze˙ze Stanisława Wyspia´nskiego 27Wrocław50-370Poland

high-porosity,open-cell AZ91 magnesium alloy foams of two pore sizes were fabricated by means of investment casting technology,using PUR foam *** casting variables such as pressure,mould temperature and metal pouring temperature were thoroughly investigated to define the most optimal casting *** mechanical properties of the fabricated foams were measured in compression tests.A potential application for the foams considered is temporary bioresorbable bone implants,therefore the mechanical properties of the foams were compared with those of cancellous bone *** with smaller pore size and lower porosity(20 PPI and 80%±87%)exhibited mechanical properties in the lower regions of the cancellous bone property range(young’s modulus 36.5±77.5 MPa),while foams with higher pore size and porosity(10 PPI and~90%)were found to have insufficient compression strength.young’s modulus 11.65±23.8),but thickening their walls and lowering their porosity below 90%yielded foams with.young’s modulus between 36.5 and 77.5 *** fractures were also investigated to determine their collapse mechanism.A series of corrosion tests in stimulated body fluid was carried out to determine their applicability as a *** Plasma Electrolytic Oxidation(PEO)process was used in a feasibility study to examine the microstructure and chemical composition of foams with protective coating.

关键词： Magnesium foams AZ91 investment casting Bone implants Plasma electrolytic oxidation