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Structure and Mechanical Properties of Ni-based Porous Superalloy

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 73-77页

作者：米国发 school of Materials Science and Engineering Henan Polytechnic University

The porous superalloy materials with hollow spherical and oriented linear pores were fabricated by means of powder metallurgy using Ni-based superalloy powders. Structure observation revealed that the pores of the porous material exhibited uniform distribution and the pores were of the same size in principle. The sintering necks created between adjacent particles on metal skeleton after sintering. The porosity of the porous material increased with increasing the addition of pore forming agent, and the hollow spherical porous material with a porosity of 81.62. were obtained when the addition of pore forming agent was 40%. The compression test indicated that this kind of materials possesses excellent energy absorption capability, and the compression resistance decreased with the increasing of porosity and pore size.

关键词： porous superalloy powder metallurgy hollow spherical pores oriented linear pores

A new method for mining deformation monitoring with GPS-RTK

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中国有色金属学会会刊：英文版 2011年第S3期21卷 659-664页

作者： GAO Jing-xiang1, 2. LIU Chao2. WANG Jian1, 2. LI Zeng-ke2. MENG Xiang-chao2.1. Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of surveying and mapping,{2. University of Mining and Technology, Xuzhou 2.1116,{2. 2. school of Environment and Spatial Informatics,{2. University of Mining and Technology, Xuzhou 2.1116,{2. Key Laboratory for Land Environment and Disaster Monitoring of State Bureau of surveying and mapping China University of Mining and Technology Xuzhou 221116 China school of Environment and Spatial Informatics China University of Mining and Technology Xuzhou 221116 China

Based on ranging intersection theory, a new method which is simple and easy to operate was proposed for data collection in the mine surface deformation monitoring with GPS-RTK centering rod measurements. It can fully eliminate the inevitable shaking error and the vertical deflection, and to some extent weaken the multipath effect on the estimates of coordinates in a relatively short period of time, using high-frequency observations. The results show that three-dimensional coordinates with a height accuracy better than 1 cm, horizontal accuracy better than 2.4 cm can be achieved through only 15-30 s continuous observation by 2. Hz high-frequency and effectively improve the measurement accuracy and efficiency of RTK, fully satisfying the high-speed and high-precision data acquisition in mine surface subsidence deformation monitoring.

关键词： GPS rover pole multipath delay deformation monitoring

REGULARITY OF WEAK SOLUTIONS TO MAGNETO-MICROPOLAR FLUID EQUATIONS

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Acta Mathematica Scientia 2010年第5期30卷 1469-1480页

作者：原保全 school of Mathematics and Informatics Henan Polytechnic University

In this article, we study the regularity of weak solutions and the blow-up criteria for smooth solutions to the magneto-micropolar fluid equations in R3. We obtain the classical blow-up criteria for smooth solutions （u,w, b）, i.e., u ∈ Lq（0, T; LP（R3） for 2.q＋3/P≤ 1with 3〈P≤∞,u∈C（[0,T）;L3（R3））or△u∈Lq（0,T,LP）for 3/2.P≤∞ satisfying 2.q＋3/P≤ 2. Moreover, our results indicate that the regularity of weak solutions is dominated by the velocity u of the fluid. In the end-point case p = ∞, the blow-up criteriacan be extended to more general spaces △u E L1 （0, T; B0∞,∞（R3）.

关键词： magneto-micropolar fluid equations regularity criteria blow-up criteria

Quick image-processing method of UAV without control points data in earthquake disaster area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 523-528页

作者： LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2. 3, GONG A-du2. 3 1. school of surveying & Land Information Engineering, {2. polytechnic University, jiaozuo 454000, china 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal University, Beijing 100875, china 3. Ministry of Civil Affairs/Ministry of Education of china Academy of Disaster Reduction and Emergency Management, Beijing Normal University, Beijing 100875, china school of surveying & Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China Ministry of Civil Affairs/Ministry of Education of china Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.

关键词： unmanned aerial vehicles SIFT algorithm blocking quickly splicing rectification

Progress in technology for the 2.05 height determination of Qomolangma Feng (Mt. Everest)

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Science china Earth Sciences 2006年第5期49卷 531-538页

作者： CHEN Junyong1,2. YUAN Janli1,2. GUO Chunxi1,2. ZHANG Yanping1 & ZHANG Peng1,2.1. State Bureau of surveying and mapping, Beijing 100830,{2. 2. school of Geodesy and Geomatics, Wuhan University, Wuhan 430079,{2. State Bureau of surveying and mapping Beijing China school of Geodesy and Geomatics Wuhan University Wuhan China

In 2.05 china carried out a new geodetic campaign for the height determination of Qo- molangma Feng——Mt. Everest (QF in short). The technical progresses in geodesy for the 2.05 campaign are presented in the paper. GPS positioning was the key technique in the campaign. After summarizing the experiences and lessons of the GPS positioning on the QF summit in the previous QF height determination campaigns, some measures were taken to raise the accuracy and reliability of the height determination with GPS techniques. In order to raise the accuracy of the height deter- mination of the QF summit with classical geodetic techniques, laser ranging was used together with the trigonometric levelling in the 2.05 campaign. It is the first time in china the thickness of the ice-snow layer on the QF summit was measured by ground penetrating radar integrated with GPS. The local gravity field and geoid in the QF area was improved on the basis of earth gravity field model integrated with new ground gravity data, DTM data and GPS leveling data in the QF area. In the 2.05 campaign the normal height and orthometric height (height above sea level) of the snow surface of the QF summit were obtained as 8846.67 m and 8847.93 m respectively. The orthometric height of the rock surface of the QF summit is 8844.43 m,and the thickness of the ice-snow layer on the QF summit is 3.50 m.

关键词： Qomolangma Feng, Mt. Everest, height determination, GPS, gravity field, ground penetrating radar.

Conceptual design,data model and key techniques of“3D Assistant”

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中国有色金属学会会刊：英文版 2011年第S3期21卷 692-698页

作者： LI Qing-yuan1, ZHANG Xuan2. JIN Yang2. ZHOU Hui3, WANG Qian-jin3,WEI Zhan-yin1 1. Key Laboratory of Geo-Informatics, Chinese Academy of surveying and mapping, Beijing 100830,{2. 2. school of Geo-Science and surveying Engineering,{2. University of Mining and Technology, Beijing 100083,{2. 3. school of Geomatics, Liaoning Technical University, Fuxin 12.000,{2. Key Laboratory of Geo-Informatics Chinese Academy of Surveying and Mapping Beijing 100830 China school of Geo-Science and surveying Engineering China University of Mining and Technology Beijing 100083 China school of Geomatics Liaoning Technical University Fuxin 123000 China

Conceptual design, data model and key techniques of "Geo-engineer 3D assistant", an underground 3D GIS oriented to geology and mine application, were discussed. In particular, the importance of high-order smoothing triangular pieces to surface's fine expression in geological modeling was emphasized. The contour mode is the most favorite mode of the three modes about surface expression: DEM, TIN and contour. Topology in underground 3D modeling with CAGD was compared. From the view of boundary and coboundary, which is soul of IS 19107 (Geographic information spatial schema), 3D underground topology was re-examined.

关键词： 3D assistant true 3D GIS fine expression of surface contour mode 3D topology

Annual integral changes of time serial NDVI in mining subsidence area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 583-588页

作者： MA Chao1, GUO Zeng-zhang1, ZHANG Xiao-ke2. HAN Rui-mei1 1. Key Laboratory of Mine Spatial Information Technologies of State Bureau of surveying & mapping, {2. polytechnic University, jiaozuo 454000, china 2. school of Coal Mining Engineering, Taiyuan University of Technology, Taiyuan 03002., china henan Polytech Univ State Bur Surveying & Mapping Key Lab Mine Spatial Informat Technol Jiaozuo 454000 Peoples R China Taiyuan Univ Technol Sch Coal Min Engn Taiyuan 030024 Peoples R China

By means of MORTRAN4 model of FLASSH module, an atmospheric correction of the SPOT II/IV data of four-year period for eight experimental coal faces of Lu'an mine area was done. The mining-affected zones were obtained with probability integral method. The normalized difference vegetation index (NDVI) and its mean were obtained by band ratio calculation at the mining subsidence area. Using FOURIER4 model of the fast Fourier transform (FFT) of discrete Fourier analysis theory, the mean NDVI time series data set was reconstructed. With the mean of NDVI transformed into amplitude and the phonological information transformed into phase, the law of NDVI variation by monthly, quarterly, annual were obtained. The annual integral of the time series of NDVI Fourier function (ANDVI) was obtained. The results show that an experience formula of ANDVI variation accompanies with mining time; A fast estimation formula of NPP by means of a coefficient of mining disturbance such as γ.

关键词： Lu’an mine area annual integral of NDVI net primary productivity coefficient of mining disturbance

Binary population synthesis study of the supersoft X-ray phase of single degenerate type Ia supernova progenitors

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Research in Astronomy and Astrophysics 2011年第8期11卷 965-973页

作者： Xiang-Cun Meng Wu-Ming Yang school of Physics and Chemistry Henan Polytechnic University Jiaozuo 454000 China Department of Astronomy Beijing Normal University Beijing 100875 China

In the single degenerate （SD） scenario for type Ia supernovae （SNe Ia）, a mass-accreting white dwarf is expected to experience a supersoft X-ray source （SSS） phase. However, some recent observations showed that the expected number of massaccreting WDs is much lower than that predicted from theory, regardless of whether they are in spiral or elliptical galaxies. In this paper, we performed a binary population synthesis study on the relative duration of the SSS phase to their whole mass-increasing phase of WDs leading to SNe Ia. We found that for about 40% of the progenitor systems, the relative duration is shorter than 2. and the evolution of the mean relative duration shows that it is always smaller than 5%, both for young and old SNe Ia. In addition, before the SNe Ia explosions, more than 55% of the progenitor systems were experiencing a dwarf novae phase and no more than 10% were staying in the SSS phase. These results are consistent with the recent observations and imply that both in early- and late-type galaxies, only a small fraction of mass-accreting WDs resulting in SNe Ia contributes to the supersoft X-ray flux. So, although our results are not directly related to the X-ray output of the SN Ia progenitor, the low supersoft X- ray luminosity observed in early type galaxies may not be able to exclude the validity of the SD model. On the contrary, it is evidence to support the SD scenario.

关键词： stars: white dwarfs -- stars: supernovae: general

A new approach toward object-based change detection

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Science china(Technological Sciences) 2010年第S1期53卷 105-110页

作者： ZHANG Guo1,2.LI Yang1 & LI ZhiJiang3 1 State Key Laboratory of Information Engineering in surveying,mapping and Remote Sensing,Wuhan University,Wuhan 430079,{2. 2.Satellite of surveying and mapping Application center,State Bureau of surveying and mapping,Beijing 100830,{2. 3 school of Printing and Packaging,Wuhan University,Wuhan 430079,{2. State Key Laboratory of Information Engineering in surveying Mapping and Remote Sensing Wuhan University Wuhan China Satellite of surveying and mapping Application center State Bureau of Surveying and Mapping Beijing China school of Printing and Packaging Wuhan University Wuhan China

Object-based change detection has been the hotspot in remote sensing image processing.A new approach toward object-based change detection is *** two different temporal images are unitedly segmented using the mean shift procedure to obtain corresponding *** change detection is implemented based on the integration of corresponding objects’ intensity and texture *** are conducted on both panchromatic images and multispectral images and the results show that the integrated measure is robust with respect to illumination changes and *** color detection is conducted to determine whether the color of the unchanged objects changes or not when dealing with multispectral *** verification work is carried out to show the accuracy of the proposed approach.

关键词： mean shift united segmentation change detection object-based intensity texture integration