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Web-based visualization of large 3D urban building models

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International Journal of Digital Earth 2014年第1期7卷 53-67页

作者： Liqiang Zhang chunming han Liang Zhang Xiaokun Zhang Jonathan Li State Key Laboratory of Remote Sensing Science Beijing Normal UniversityBeijingChina The Center for Earth Observation and Digital Earth Chinese Academy of ScienceBeijingChina Department of Computer Science Beijing Electronic Science and Technology InstituteBeijingChina Department of Geography and Environmental Management Faculty of EnvironmentUniversity of WaterlooWaterlooCanada

Adaptive rendering of large urban building models has become an important research issue in three-dimensional(3D)geographic information system(GIS)*** study explores a way for rendering web-based 3D urban building models.A client-server hybrid rendering approach is presented for large 3D city models,stored on a remote server through a *** approach combines an efficient multi-hierarchical building representation with a novel image-based method,3D image impostor generated on demand by a remote *** approach allows transferring complex scenes progressively while keeping high visualization *** also evaluated the rendering and data transferring performance of the proposed approach.

关键词： urban building models progressive transmission client-server hybrid 3D visualization

Nerve regeneration following implantation of axotomized nerves pretreated with gamma radiation

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Neural Regeneration Research 2008年第10期3卷 1121-1123页

作者： Xinyuan Wang Dehai Chang Shihua Xie chunming han Jinsheng Sheng Center of Orthopedics ancl Trauma Tenth Hospital of Lanzhou Military Area Command of Chinese PLA Wuwei 733000 Gansu Province China

BACKGROUND： It has been shown that irradiation to the neurolemma can reduce immuuogenicity. However, it is still poorly understood whether the degenerated nerve can affect peripheral nerve regeneration OBJECTIVE： To observe the effect of radiation-damaged nerve transplantation on functional recovery of the peripheral nerve. DESIGN, TIME AND SETTING： Self-control animal trial was performed at the Experimental Center of Orthopedics, Tangdu Hospital of Fourth Military Medical University from January to October 2005. MATERIALS： Fifty-four healthy, Chinese rabbits, irrespective of gender, were randomly divided into experimental （n = 36） and control （n = 18） groups. A 60 Co Y -radiation machine and NDI-200 nerve electromyograph were provided by the Experimental Center of Orthopedics, Tangdu Hospital of Fourth Military Medical University. METHODS： A median incision was made in the posterior right thigh of rabbits after abdominal anesthesia. A 30-mm segment of sciatic nerve was excised from the inferior margin of the piriform muscle to the tibiofibular intersection. The sciatic nerve in the experimental group was sterilely radiated with 350 Gy for 9.5 minutes. The damaged nerve segment was then re-transplanted. In the control group, the sciatic nerve was re-transplanted directly following excision. Nerve conduction velocity was determined at 4, 6, and 8 months post-surgery. MAIN OUTCOME MEASURES： Functional assessments, such as gait, nutritional status of skin on dorsum of foot, toe spreading reflex, and foot holding, were made between 1 and 180 days post-surgery. The common peroneal nerve and tibial nerve reflexes under clamping were observed at 4, 6, and 8 months post-surgery to evaluate functional restoration of the peripheral nerve. Electromyogram was performed to observe nerve conduction velocity. RESULTS： From postoperative days 1 to 26, the limbs that were transplanted with irradiated nerve exhibited dragged walking, foot drop, sole ulcers, depilation, self-induced i

关键词： axotomized nerve gamma radiation re-transplantation toe-spreading reflex

Joint shape and color descriptors for 3D urban model retrieval

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International Journal of Digital Earth 2016年第11期9卷 1117-1134页

作者： Liang Zhang Liqiang Zhang Xiaojing Yao P.Takis Mathiopoulos chunming han State Key Laboratory of Remote Sensing Science Beijing Normal UniversityBeijingPeople’s Republic of China The Institute of Remote Sensing and Digital Earth Chinese Academy of SciencesBeijingPeople’s Republic of China Department of Informatics and Telecommunications University of AthensAthensGreece

With the rapid development of photogrammetry,computer vision and three-dimensional(3D)modeling technologies,it is possible to efficiently construct detailed 3D urban ***,large corpora of 3D models,such as the Google 3D Warehouse,are now becoming freely available on the *** to find the proper 3D urban models is a challenging research *** this paper,we join shape descriptors and color descriptors for 3D urban model *** query objects are localized and segmented automatically from the input images by using a new selective search voting *** combining the normalization with the light field descriptor,the Horizontal Light Descriptor is introduced to measure the shape similarity among the normalized urban *** color descriptors are used to represent the color information of the urban *** two types of descriptors are joined to search 3D urban models similar to the query *** results have shown the effectiveness of our approach.

关键词： 3D urban models shape descriptor color descriptor model retrieval

Deep Structure and Metallogenic Processes of the Altai-Junggar-Tianshan Collage in Southern Altaids

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Acta Geologica Sinica(English Edition) 2019年第5期93卷 1163-1168页

作者： XIAO Wenjiao SONG Dongfang han chunming WAN Bo ZhanG Jien AO Songjian ZhanG Zhiyong Xinjiang Research Center for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

The Altai-Junggar-Tianshan collage in southern Altaids is an important metallogenic domain in Central Asia that contain world-class copper-iron-nickel *** an accretionary-type metallogenic system,the metallogenic processes of the Altai-Junggar-Tianshan collage is essential in understanding the genetic mechanism of ore deposits in *** in this paper we present a brief introduction to the project on the western part of the Southern Altaids,entitled"The deep structure and metallegenic processes of the North China accretionary metallogenic systems".This project mainly focuses on the deep structure and metallogenic background of the Altai-Junggar-Tianshan collage by integrated studies from field geology,structural mapping,geochemistry and geophysical *** new geological and geophysical methods will be applied to make transparency of the Kalatongke and Kalatage ore *** will update our understanding of the geodynamic processes of metallogenesis and lead to the development and foundation of new metallogenic theories in accretionary orogens.

关键词： accretionary orogen metallogenesis deep structure northern Xinjiang Altaids

Neoproterozoic-Paleozoic Tectonic Evolution of the Northeastern Tarim Block： Constraints from ^40Ar/^39Ar Geochronology in the Kuluketage Area, NW China

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Acta Geologica Sinica(English Edition) 2017年第4期91卷 1231-1247页

作者： ZhanG Zhiyong ZHU Wenbin ZHENG Dewen ZHENG Bihai XIAO Wenjiao LI Daming han chunming State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beij'ing 100029 China School of Earth Sciences The University of Melbourne Victoria 3010 Australia State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beo'ing 100029 China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China

Seventeen new ^40Ar/^39Ar analyses reported for ten Tarim Precambrian basement samples from the Kuluketage area, are applied to reconstruct the regional thermo-tectonic history together with previously published data. Eight samples were taken adjacent to the Xingdi and Xinger faults, major structures in the study area, whereas a further two were sampled at some distance from the faults. 4^40Ar/^39Ar data from the latter record rapid cooling following a Neoproterozoic magmatic/metamorphic event and mild Paleozoic thermal disturbance. Paleozoic ^40Ar/^39Ar ages from the study area, as well as from the Central Tianshan and eastern Southern Tianshan suggest two strong deformational periods at ~390 Ma and ~300 Ma. During the older period, argon isotopic systems were reset/disturbed by high temperature related to arc magmatism resulting from subduction of the South Tianshan paleo-oceanic crust, possibly in combination with reactivation of Precambrian faults. The younger period is characterized by widespread late Carboniferous-early Permian intracontinental deformation, which is related to the final amalgamation of the Central Asian Orogenic Belt. Previously published apatite fission track data attest to a long history of post-collisional cooling, which is attributed to continued propagation of deformation within the Central Asian Orogenic Belt.

关键词： ^40Ar/^39 geochronology Northeastern Tarim Block South Tianshan Ocean Neoproterozoic-Paleozoic thermo-tectonic evolution

Rhenium-Osmium Isotope Constraints on the Origin of the Tianyu Cu-Ni Deposit in the East Tianshan Orogenic Belt, Xinjiang, NW China

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Acta Geologica Sinica(English Edition) 2022年第2期96卷 525-535页

作者： han chunming XIAO Wenjiao AO Songjian ZhanG Jien SONG Dongfang ZhanG Zhiyong SONG Shuaihua XIE Mingcai Key Laboratory of Mineral Resource Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Xinjiang Research Center for Mineral Resources Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China

The Tianyu Cu-Ni sulfide deposit occurs in the north margin of the Central Tianshan Arc in East Tianshan orogenic belt, Xinjiang, NW China. The intrusions consist of gabbro, peridotite, and olivine pyroxenite. The peridotite and pyroxenite are the main host rock for the Cu-Ni ores. Rhenium and osmium isotopic analyses of Ni-and Cu-bearing sulfide minerals from the deposit have been used to determine the source of osmium, and by inference, the sources of ore metals. Sulfide ore samples have Os and Re concentrations varying in the ranges 1.85 to 4.58 ppb and 93.56 to 146.00 ppb, respectively. An initial ^(187)Os/^(188)Os ratio ranges from 0.86 to 1.23 for the ores and the γOs values from 592 to 2227. Osmium isotopic data suggest that the Tianyu intrusion and associated Cu-Ni mineralization has derived from crustal-contaminated mantle melts. The intrusions early show island-arc geochemical signatures, which indicate that the Hulu mafic–ultramafic intrusions, along with the Cu-Ni deposit, formed as a result of subduction of oceanic crust in the Early Permian.

关键词： rhenium-osmium isotope Cu-Ni deposit Tianyu intrusion East Tianshan orogenic belt Xinjiang

Accretionary processes and metallogenesis of the Central Asian Orogenic Belt:Advances and perspectives

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Science China Earth Sciences 2020年第3期63卷 329-361页

作者： Wenjiao XIAO Dongfang SONG Brian FWINDLEY Jiliang LI chunming han Bo WAN Ji'en ZhanG Songjian AO Zhiyong ZhanG Research Centre for Mineral Resources Xinjiang Institute ofEcology and GeographyChinese Academy of SciencesUrumqi 830011China State Key Laboratory ofLithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Geology University of LeicesterLeicester LEI 7RHUK

As one of the largest Phanerozoic orogens in the world,the Central Asian Orogenic Belt(CAOB)is a natural laboratory for studies of continental dynamics and *** paper summarizes the research progresses of the accretionary processes and metallogenesis of the CAOB since the Peopled Republic of China was founded,and puts forward the prospect for future *** the early period(1950s-1970s),several geological theories were applied to explain the geological evolution of Central *** the early period of China's reform and opening-up,the plate tectonics theory was applied to explain the evolution of the northern Xinjiang and Xingmeng regions,and the opinion of subduction-collision between Siberian Kazakhstan and China-North Korea-Tarim plates was *** idea of the Solonker-Yanbian suture zone was *** the 1990s,the study of the CAOB entered a period of rapid *** school of scholars including geologists from the former Soviet Union proposed a multi-block collision model for the assemblage of the *** contrast,another school of scholars,led by a Turkish geologist,Celal Sengor,proposed that the Altaids was formed through the growth and strike-slip duplicates of a single island arc,and pointed out that the Altaids is a special type of collisional *** this period,Chinese geologists carried out a lot of pioneering researches on ophiolites and high-pressure metamorphic rocks in northern China,and confirmed the main suture zones *** 1999,the concept of"Central Asian metallogenic domain"was proposed,and it became one of the three major metallogenic domains in the *** the 21st century,given the importance for understanding continental accretion and metallogenic mechanism,the CAOB has become the international academic *** has laid out a series of scientific research projects in Central Asia.A large number of important scientific research achievements have been spawned,including the tecto

关键词： CAOB Accretionary orogenic processes Metallogenesis Research progress Research frontier

Anatomy of composition and nature of plate convergence： Insights for alternative thoughts for terminal India-Eurasia collision

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Science China Earth Sciences 2017年第6期60卷 1015-1039页

作者： XIAO WenJiao AO SongJian YANG Lei han chunming WAN Bo ZhanG Ji'En ZhanG ZhiYong LI Rui CHEN ZhenYu SONG ShuaiHua State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Science Chinese Academy of Sciences Beijing 100101 China University of Chinese Academy of Sciences Beijing 100049 China

The pattern and timing of collision between India and Eurasia have long been a major concern of the international community. However, no consensus has been reached hitherto. To explore and resolve the disagreements in the Himalayan study,in this paper we begin with the methodology and basic principles for the anatomy of composition and nature of convergent margins,then followed by an effort to conduct a similar anatomy for the India-Eurasia collision. One of the most common patterns of plate convergence involves a passive continental margin, an active continental margin and intra-oceanic basins together with accreted terranes in between. The ultimate configuration and location of the terminal suture zone are controlled by the basal surface of the accretionary wedge, which may show fairly complex morphology with Z-shape and fluctuant geometry. One plausible method to determine the terminal suture zone is to dissect the compositions and structures of active continental margins. It requires a focus on various tectonic elements belonging to the upper plate, such as accretionary wedges, high-pressure(HP)-ultra-high-pressure(UHP) metamorphic rocks, Barrovian-type metamorphic rocks and basement nappes, together with superimposed forearc *** geological records can define the extreme limits and the intervening surface separating active margin from the passive one,thus offering a general sketch for the surface trace of the terminal suture zone often with a cryptic feature. Furthermore, the occurrence of the cryptic suture zone in depth may be constrained by geophysical data, which, in combination with outcrop studies of HP-UHP metamorphic rocks, enables us to outline the terminal suture zone. The southern part of the Himalayan orogen records complicated temporal and spatial features, which are hard to be fully explained by the classic "two-plate-one-ocean" template,therefore re-anatomy of the compositions and nature for this region is necessitated. Taking advantage of

关键词： Himalayan orogen Yarlung-Zangbo ophiolite Tethyan Himalayan Sequence India-Eurasia collision Anatomy of orogeny

Geological Characteristics and Metallogenic Setting of Representative Magmatic Cu-Ni Deposits in the Tianshan-Xingmeng Orogenic Belt, Central Asia

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Acta Geologica Sinica(English Edition) 2019年第5期93卷 1205-1218页

作者： han chunming XIAO Wenjiao SU Benxun ZhanG Xiaohui WAN Bo SONG Dongfang ZhanG Zhiyong ZhanG Jien WANG Zhongmei XIE Mingcai Key Laboratory of Mineral Resources Chinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Sciences Chinese Academy of SciencesBeijing 100029China State Key Laboratory of Lithospheric evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

A great number of magmatic Cu-Ni deposits(including Kalatongke in Xinjiang and Hongqiling in Jilin) are distributed over a distance of almost 3000 km across the Tianshan-Xingmeng Orogenic Belt, from Tianshan Mountains in Xinjiang in the west, to Jilin in eastern China in the east. These deposits were formed during a range of magmatic episodes from the Devonian to the Triassic. Significant magmatic Cu-Ni-Co-PGE deposits were formed from the Devonian period in the Nalati arc(e.g. Jingbulake Cu-Ni in Xinjiang), Carboniferous period in the Puerjin-Ertai arc(e.g. Kalatongke Cu-Ni-Co-PGE in Xinjiang), Carboniferous period in the Dananhu-Touquan arc(e.g. Huangshandong, Xiangshan and Tulaergen in estern Tianshan, Xinjiang) to Triassic period in the Hulan arc(e.g. Hongqiling Cu-Ni in Jilin). In addition to the overall tectonic, geologic and distribution of magmatic Cu-Ni deposits in the Tianshan-Xingmeng Orogenic Belt, the metallogenic setting, deposit geology and mineralization characteristics of each deposit mentioned above are summarized in this paper. Geochronologic data of Cu-Ni deposits indicate that, from west to east, the metallogenic ages in the Tianshan-Xingmeng Orogenic Belt changed with time, namely, from the Late Caledonian(~440 Ma), through the Late Hercynian(300-265 Ma) to the Late Indosinian(225-200 Ma). Such variation could reflect a gradual scissor type closure of the paleo Asian ocean between the Siberia Craton and the North China Craton from west to east.

关键词： Geochronology magmatic Cu-Ni-Co-PGE deposits Tianshan-Xingmeng Orogenic Belt Central Asia