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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1, 2. WU Li-xin1, 2. LI Hui-ying3 1. college of resources and {2. engineering, northeastern university, shenyang 110004, china 2. Academy of Disaster Reduction and Emergency Management, Ministry of {2. Affairs and Ministry of Education, Beijing Normal university, Beijing 100875, china 3. college of Computer Science and Technology, Jilin university, Changchun 130012. china [a] college of resources and {2. engineering Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] college of Computer Science and Technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

In situ experiments on width and evolution characteristics of excavation damaged zone in deeply buried tunnels

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Science china(Technological Sciences) 2011年第S1期54卷 167-174页

作者： LI ShaoJun 1,FENG XiaTing 1,LI ZhanHai 3,CHEN BingRui 1,JIANG Quan 1,WU ShiYong 2.HU Bin 2.&XU JinSong 2.1 State Key Laboratory of Geomechanics and Geotechinical engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,china 2.Ertan Hydropower Development Company,Ltd.,Chengdu 610051,china 3 School of resources and civil engineering,northeastern university,shenyang 110004,china 1. State Key Laboratory of Geomechanics and Geotechinical engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China3. School of Resources and Civil Engineering Northeastern University Shenyang 110004 China2. Ertan Hydropower Development Company Ltd. Chengdu 610051 China

The seven long tunnels of Jinping II hydropower station are deeply *** width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and *** order to study this problem,several specific experimental tunnels with different overburden and geometric sizes were excavated at this *** borehole camera,sliding micrometer,cross-hole acoustic wave equipment and acoustic emission apparatus were *** paper introduced the comprehensive in situ experimental methods through pre-installed facilities and pre-drilled *** properties of the surrounding rock mass,including cracks,deformation,elastic wave and micro fractures,were measured during the whole process of the tunnel *** width and characteristics of formation and evolution of tunnels EDZ were analyzed under different construction methods involving of TBM and drilling and blasting,the test tunnels were excavated by full-face or two *** relationships between EDZ and tunnel geometry sizes,overburden and excavation method were described as *** results will not only contribute a great deal to the analysis of rock mass behavior in deeply buried rock mass,but also provide direct data for support design and rockburst prediction.

关键词： deeply buried tunnel excavation damaged zone evolution characteristics in situ experiments

Experimental study of dynamic mechanical properties of reactive powder concrete under high-strain-rate impacts

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Science china(Technological Sciences) 2010年第9期53卷 2435-2449页

作者： JU Yang1,2.LIU HongBin1,SHENG GuoHua1,3 & WANG HuiJie1 1 State Key Laboratory of Coal resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete,china {2. of Mining and Technology,Beijing 100083,china 2.Department of Mechanical and Manufacturing engineering,{2. of Calgary,2.00 {2. Drive,AB T2. 1N4,Canada 3 School of resources and civil engineering,northeastern {2.,{12. 110004,china 1. State Key Laboratory of Coal resources and Safe Mining Beijing Key Laboratory of Fracture and Damage Mechanics of Rocks and Concrete China University of Mining and Technology Beijing 100083 China2. Department of Mechanical and Manufacturing Engineering University of Calgary 2500 University Drive AB T2N 1N4 Calgary Canada3. School of Resources and Civil Engineering Northeastern University Shenyang 110004 China

The dynamic mechanical properties of reactive powder concrete subjected to compressive impacts with high strain rates ranging from 10 to 1.1×102.s-1 were investigated by means of SHPB (split-Hopkinson-pressure-bar) tests of the cylindrical specimens with five different steel fiber volumetric *** properties of wave stress transmission,failure,strength,and energy consumption of RPC with varied fiber volumes and impact strain rates were *** influences of impact strain rates and fiber volumes on those properties were characterized as *** general forms of the dynamic stress-strain relationships of RPC were modeled based on the experimental *** investigations indicate that for the plain RPC the stress response is greater than the strain response,showing strong brittle *** RPC with a certain volume of fibers sustains higher strain rate impact and exhibits better deformability as compared with the plain *** a constant fiber fraction,the peak compressive strength,corresponding peak strain and the residual strain of the fiber-reinforced RPC rise by varying amounts when the impact strain rate increases,with the residual strain demonstrating the greatest *** the fiber content makes trivial contribution to improving the residual deformability of RPC when the impact strain rate is *** tests also show that the fiber content affects the peak compressive strength and the peak deformability of RPC in a different *** a constant impact strain rate and the fiber fraction less than 1.75%,the peak compressive strength rises with an increasing fiber *** peak compressive strength tends to decrease as the fiber volume exceeds 1.75%.The corresponding peak strain,however,incessantly rises with the increasing fiber *** total energy Edisp that RPC consumed during the period from the beginning of impacts to the time of residual strains elevates with the fiber volume increment as long as the fiber fraction

关键词： impact reactive powder concrete (RPC) high strain rate dynamic strength energy consumption dynamic stress-strain response

Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2. GUO Zeng-zhang1, 2. WU Li-xin3, ZHANG Qin4 1. School of Survey and Land Information engineering, Henan Polytechnic university, Jiaozuo 454003,{2. 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003,{2. 3. college of resources and civil engineering, northeastern university, shenyang 110819,{2. 4. college of Geology engineering and Geomatics, Chang’an university, Xi’an 710054,{2. [a] School of Survey and Land Information engineering Henan Polytechnic University Jiaozuo 454003 China [b] Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China [c] college of resources and {2. engineering Northeastern University Shenyang 110819 China [d] college of Geology engineering and Geomatics Chang'an University Xi'an 710054 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

Preparation and characterization of uniform circinate aggregates of sheet ZnO nanoparticles

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Rare Metals 2008年第1期27卷 36-40页

作者： LIU Jiaxiang DING Deling WANG Lisheng and HAN Yuexin The State Key Laboratory of Chemical Resource engineering College of Materials Science and Engineering Beijing University of Chemical Technology Be~iing100029 China School of resources and civil {2. Northeastern University Shenyang 110004 China

Uniform circinate aggregates of sheet ZnO nanoparticles with a specific surface area of 2. m^2.g^-1 were prepared by the direct precipitation *** circinate aggregates were hexagonal ZnO,with the wall thickness ranging from 0.5 to 1 μm and the diameter ranging from 5 to 10 μ*** backs of the circinate aggregates were regularly arranged by numerous sheet ZnO nanoparticles with a thickness of 30-80 nm and a diameter of 300-400 *** precursors were aggregates of sheet Zn5（CO3）2.OH）6 nanoparticles,which were decomposed into ZnO by calcining in air in the range of 2.0-2.5°C,and the ZnO retained the similar special *** C2.5OH content had a significant effect on the formation of sheet *** centripetal force,the Van der Waals force,and the hydrogen bond were deduced as the driving forces of the formation of circinate.

关键词： nano-ZnO circinate aggregates preparation technology microstructure characterization

Fault Tree Analysis on Failure of Bag Filter in Power Plant

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Fault Tree Analysis on Failure of Bag Filter in Power Plant

PROPERTY AND METALLOGENIC CHARACTERISTICS OF ALKALI-RICH PORPHYRY IN WESTERN MARGIN OF YANGTZE PLATFORM

2.06（沈阳）国际安全科学与技术学术研讨会

作者： LI He college of resources & {2. engineering northeastern university shenyang 110004 china

＜正＞The major pollution of air contamination is the dust of power plant, the total amount of emission is beyond seventy percent. bag filter has high efficiency of dust removal will lead to the emission concentration decrease to 5 - 30mg/m3 , which is effective management to reach the emission standard. The failure of baghouse will disturb the running of equipment. FTA has been used to analyze the failure of filter, and based on success tree, some measures prompted also.

关键词： power plant bag filter filter failure fault tree dust

来源： cnki会议评论

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Journal of Central South university 1998年第2期10卷 57-60页

作者： Hu Xiangzhao (college of resources, Environment and {2. engineering,Central South university of Technology, Changsha 410083, china) college of resources Environment and Civil Engineering Central South University of Technology Changsha 410083 China

The age of alkali rich porphyries in the western margin of Yangtze Platform is 30—50 Ma; the minerals mainly are orthoclase, quartz, plagioclase; the chemical composition is alkali rich [(K 2.+Na 2.)>8%],high potash[(K 2.+Na 2.)=5.09%-8.30%]; the content of  REE  is relatively low, LREE is concentrated, without anomaly of europium; the average initial ratio of 87 Sr/ 86 Sr is 0.7073; the value of δ 34 S similar to that of the meteoritic sulfur; the ratio of Pb isotope corresponds to that of upper mantle; metallogenic types belong to Cu, Mo, Au, Ag, Pb, Zn polymetal mineralization and rare, rare earth metal mineralization.

关键词： petrology geochemistry alkali rich porphyry metallogenic characteristics

SCGM(1,m)_c model with time-lag and its application in deformation analysis

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Journal of Central South university of Technology 2001年第1期8卷 40-44页

作者： LI Zhi wei 1, LI Tao 1,ZHU Jian jun 1,WANG Ren qian 2.(1.college of resources, Environment and {2. engineering, Central South university, Changsha 410083, china 2.Department of {2. engineering, Huaqiao university, Quanzhou 35002., china) 1. college of resources Environment and Civil Engineering Central South University 410083 Changsha China 2. Department of civil engineering Huaqiao University 350029 Quanzhou China

Originated in the early 1990s, SCGM(1, m ) c model has enjoyed widespread application in the fields of urban planning, society economy prediction and modal control in recent years. However, none of these applications have taken account of time lag effects in the modeling process. Aiming at overcoming the defect, the authors introduced time lag items into SCGM(1, m ) c model and developed a SCGM(1, m ) c model with time lag, then discusses in detail some principal problems in the model, such as parameters estimation, model verifying, model prediction, etc. The model was used on a real slope monitoring project and compared with the conventional SCGM(1, m ) c model. The results show an improvement of average models precision from 1.32. to 0.2.8 and total average of relative prediction errors from 12.41% to 7.98% when the modeling data length ranges from 2. to 48 in the slope monitoring case.

关键词： grey system SCGM(1,m)c time-lag deformation analysis

Influence of vibration on granular flowability and its mechanism of aided flow

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Journal of Central South university of Technology 2001年第4期8卷 252-257页

作者： WU Ai xiang,SUN Ye zhi,LI Jian hua (college of resources, Environment and {2. engineering, Central South university, Changsha 410083, china) 1. college of resources Environment and Civil Engineering Central South University 410083 Changsha China

Regarding flowing granular media as weak transverse isotropic media, the phase velocity expressions of wave P, wave SH and wave SV were deduced, the propagation characteristics of waves in flowing granular media were analyzed. The experiments show that vibration has great influence on granular fluidity. The wavefront of wave P is elliptic or closely elliptic, the wavefront of wave SH is elliptic, and the wavefront of wave SV is not elliptic. Wave propagation in the granular flowing field attenuates layer after layer. The theory and experiment both substantiate that the density difference is the key factor which leads to the attenuation of vibrating energy. In terms of characteristics of wave propagation one can deduce that vibrating waves have less influence on flowability of granules when the amplitude and frequency are small. However, when the amplitude and frequency increase gradually, the eccentricity of ellipsoid, the viscosity resistance and inner friction among granules, and shear intensity of granules decrease, and the loosening coefficient of granules increases, which shows the granules have better flowability.

关键词： granular media vibrating aided flow body wave mechanism