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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 University of Mining and Technology,Beijing 100083,china 2.Department of Mechanical and Manufacturing engineering,University of Calgary,2.00 University Drive,AB T2. 1N4,Canada 3 School of resources and civil engineering,northeastern University,shenyang 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, china 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic University, Jiaozuo 454003, china 3. college of resources and civil engineering, northeastern University, shenyang 110819, china 4. college of Geology engineering and Geomatics, Chang’an University, Xi’an 710054, china [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

Wave propagation and energy dissipation in viscoelastic granular media

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Journal of Central South University 2001年第3期13卷 185-188页

作者： SUN Ye-zhi 1, WU Ai-xiang 1, LI Jian-hua 1,2.(1. college of resources, Environment and {2. engineering, Central South Unive rsity, Changsha 410083, china 2. The 5th Building Company in Guangdong Province, Shaoguan 512.2., china) 1. college of resources Environment and Civil Engineering Central South University 410083 Changsha China 2. The 5th Building Company in Guangdong Province 512026 Shaoguan China

In terms of viscoelasticity, the relevant theory of wave i n granular media is analyzed in this paper. Under the conditions of slight deforma tion of granules, wave equation, complex number expressions of propagation vecto r and attenuation vector, attenuation coefficient expressions of longitudinal wa ve and transverse wave, etc, are analyzed and deduced. The expressions of attenu ation coefficients of viscoelastic longitudinal wave and transverse wave show th a t the attenuation of wave is related to frequency. The higher the frequency is, the more the attenuation is, which is tested by the laboratory experiment. In a ddi tion, the energy dissipation is related to the higher frequency wave that is abs orbed by granular media. The friction amongst granular media also increase the e nergy dissipation. During the flowing situation the expression of transmission f actor of energy shows that the granular density difference is the key factor whi ch leads to the attenuation of vibrating energy. This has been proved by the exp eriment results.

关键词： viscoelastic granular media wave motion energy dissipation flowing situation

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

Combination of drainage, water supply and environmental protection as well as rational distribution of water resource in Zhengzhou mining district

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Science china Earth Sciences 2005年第10期48卷 1768-1779页

作者： WU Qiang1, LI Duo1,2. DI Zhiqiang3, MIAO Ying3, ZHAO Suqi4 & GUO Qiwen5 1. Resource Exploitation engineering college, CUMT, Beijing 100083,{2. 2. Shijiazhuang engineering college, University of Economics, Shijiazhuang 050031,{2. 3. shenyang Institute of Geology and Mineral resources, shenyang 110032.{2. 4. State Adminstration of Coal Mine Safety, Beijing 100013,{2. 5. Zhengzhou Coal Mine Company (Group), Zhengzhou 452.71,{2. Resource Exploitation engineering college CUMT Beijing China Shijiazhuang engineering college University of Economics Shijiazhuang{2. shenyang Institute of Geology and Mineral resources shenyang china State Adminstration of Coal Mine Safety Beijing china Zhengzhou Coal Mine Company (Group) Zhengzhou china

The geological condition of coalfield is much complex in china. With increasing in mining depth and drainage amount, the contradiction of drainage, water supply and environ-mental protection is becoming more and more serious. However, the contradiction can be solved by the scientific management of optimizing combination of drainage, water supply and environ-mental protection. The Philip multiple objectives simplex method used in this article has searched for a possible solution at the first step, and then it goes on searching to find out whether there is a weight number that can lead the solution to the biggest. It can reduce the randomness and diffi-culty of traditional weight method which determine the weight number artificially. Some beneficial coefficients are vague and the number is larger in the model of water resource dispatch. So the vague layer analysis method can consider these vague factors fully, combining the qualitative and quantitative analysis together. Especially, this method can quantify the experiential judge-ment of policy decider, and it will turn to be more suitable if the structure of objective factors is complex or the necessary data are absent. In the paper, the two methods above are used to solve the plans of drainage, water supply and optimizing distribution of water resource in the Zhengzhou mining district.

关键词： combination of drainage, water supply and environmental protection, Philip multiple objective simplex method, vague layer analysis method, distribution of water resource.

Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

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Science china Earth Sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2. LIU Han1, PAN Yinghua3, ZHAO Jun2. ZHAO Shiwei2.& YANG Yonghui2.1. The Key Laboratory of Modern Precision Agriculture System Integration Research, college of Hydraulic and civil Engineer-ing,{2. Agricultural University, Beijing 100083,{2. 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Yangling 712.00,{2. 3. Geographic and resources Management college, Yantai Normal University, Yantai 2.402.,{2. 1. The Key Laboratory of Modern Precision Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing 100083 China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Yangling 712100 China 3. Geographic and resources Management college Yantai Normal University Yantai 264025 China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2.cases were conducted. Case Ⅰ was done under a rainfall intensity of 2. mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 2.° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82./1.39% and4.49%/3.52.% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.

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