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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 civil engineering, northeastern university,{2., china 2. Academy of Disaster Reduction and Emergency Management, Ministry of civil Affairs and Ministry of Education, Beijing Normal university, Beijing 100875, china 3. college of Computer Science and Technology, Jilin university, Changchun 130012. china college of resources and {2. engineering Northeastern University Shenyang 110004 China Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China 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

Mechanical parameter evolutions and deterioration constitutive model for ductile-brittle failure of surrounding rock in high-stress underground engineering

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Underground Space 2024年第2期15卷 131-152页

作者： zhi Zheng Ronghua li Qiang Zhang Xiaohua Huang Wei wang Shuling Huang State Key Laboratory of Featured Metal Materials and life-cycle Safety for Composite Structures Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 110819China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China Key Laboratory of Ministry of Education for Geomechanics and Embankment engineering Hohai UniversityNanjing 210098China Key Laboratory of Geotechnical Mechanics and engineering of Ministry of Water resources Yangtze River Scientific Research InstituteWuhan 430010China

The deep surrounding rock is usually in the true triaxial stress state,and previous constitutive models based on the understanding of uniaxial and conventional triaxial test results have difficulty characterizing the degradation and fracture process of rock ductile–brittle failure under true triaxial stress ***,this study conducted a series of true triaxial tests to obtain the understanding of the ductile–brittle behaviour of rock,and then combined the test results and the Mogi–Coulomb strength criterion,and proposed calculation methods for the elastic modulus E,cohesion c and internal friction angle u and the evolution functions of E,c and u of rock under true triaxial *** the decreasing of the minimum principal stress r3 or increasing of the intermediate principal stress r2.the marble post-peak stress drop rate gradually increases,the ductility gradually weakens,and the brittleness significantly *** calculation method and evolution function of rock E,c and u under true triaxial stress were proposed.E decreased at first and then tended to remain stable with the increasing of equivalent plastic strain increment dep.c and u slowly increased at first and then rapidly *** a method of parameter degradation rate to realize post-peak stress drop rate to reflect the ductile–brittle characteristics,a new three-dimensional ductile–brittle deterioration mechanical model(3DBDM)was *** proposed model can accurately characterize the influence of r2.and r3 on mechanical parameters,the ductile–brittle behaviour of rock under true triaxial stresses,and the asymmetric failure characteristics of surrounding rock after excavation of deep underground *** proposed model can be reduced to elastic–perfectly plastic,elastic–brittle,cohesion weakening friction strengthening(CWFS),Mohr–Coulomb,and Drucker–Prager models.

关键词： True triaxial stress Post-peak characteristics 3D deterioration model Elastic modulus evolution Cohesion and friction angle evolution

MXene:Promising materials for magnesium-ion batteries

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Chinese Journal of Chemical engineering 2024年第5期69卷 199-211页

作者： liuyu Song Haibo li Pengkai wang Yu Shang Yue Yang Zhaoyu wu School of resources and civil {2. Northeastern UniversityShenyang 110004China

Magnesium-ion batteries(MIBs)have attracted extensive attention due to their high theoretical capacity,superior safety,and low ***,the development of MIBs is hindered by the lack of cathode materials with long cycle life and rate *** stands out as a prime choice for MIB cathode or collector for anode-free magnesium batteries(AFMBs)because of its larger surface area,adjustable surface properties,and good electrical *** this paper,we summarized the preparation and layering methods of MXene and discussed the prospects of MXene as a cathode or collector for *** review will be immensely beneficial in critically analyzing the synthesis techniques and the applications of MXene material as MIB cathode or AFMB *** addition,the challenges of the preparation and layering were concluded,along with raising the research strategies of MXene for storing Mg ions.

关键词： MXene Nanomaterials Electrochemistry Optimization Magnesium-ion batteries(MIBs)

The Chinese Society of Clinical Oncology(CSCO):clinical guidelines for the diagnosis and treatment of gastric cancer

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Cancer Communications 2019年第1期39卷 75-105页

作者： Feng-Hua wang lin Shen Jin li zhi-Wei Zhou Han liang Xiao-Tian Zhang Lei Tang Yan {2. Jing Jin Yu-Jing Zhang Xiang-lin Yuan Tian-Shu liu Guo-{2. li Qi wu hui-Mian Xu Jia-Fu Ji Yuan-Fang li {2. wang Shan Yu Hao liu Wen-Long Guan Rui-Hua Xu Department of Medical Oncology Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhou 510060GuangdongP.R.China Department of Gastrointestinal Oncology Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education)Department of Gastrointestinal OncologyPeking University Cancer Hospital and InstituteBeijing 100142P.R.China Department of Oncology Shanghai East HospitalTongji University School of MedicineShanghai 200120P.R.China Department of Gastric Surgery Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhou 510060GuangdongP.R.China Department of Gastric Cancer Tianjin Medical University Cancer Institute&HospitalNational Clinical Research Center of CancerTianjin’s Clinical Research Cancer for CancerKey Laboratory of Cancer Prevention and TherapyTianjin 300060P.R.China Medical Imaging Department Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education)Department of Gastrointestinal OncologyPeking University Cancer Hospital and InstituteBeijing 100142P.R.China Pathology Laboratory of Gastrointestinal Tumor The First Hospital of China Medical UniversityShenyang 110001LiaoningP.R.China Department of Radiation Oncology National Cancer CenterChina and Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021P.R.China Department of Radiotherapy Sun Yat-sen University Cancer CenterState Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhou 510060GuangdongP.R.China Department of Medical Oncology Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and TechnologyWuhan 430030HubeiP.R.China Department of Medical Oncology Zhongshan Hospital Affiliated to Fudan UniversityShanghai 200032P.R.China Department of General Surgery Nanfang Hospital Affi

china is one of the countries with the highest incidence of gastric *** are differences in epidemiological characteristics,clinicopathological features,tumor biological characteristics,treatment patterns,and drug selection between gastric cancer patients from the Eastern and Western ***-Chinese guidelines cannot specifically reflect the diagnosis and treatment characteristics for the Chinese gastric cancer *** Chinese Society of Clinical Oncology(CSCO)arranged for a panel of senior experts specializing in all sub-specialties of gastric cancer to compile,discuss,and revise the guidelines on the diagnosis and treatment of gastric cancer based on the findings of evidence-based medicine in china and *** referring to the opinions of industry experts,taking into account of regional differences,giving full consideration to the accessibility of diagnosis and treatment {2.,these experts have conducted experts’consensus judgement on relevant evidence and made various grades of recommendations for the clinical diagnosis and treatment of gastric cancer to reflect the value of cancer treatment and meeting health economic *** guideline uses tables and is complemented by explanatory and descriptive notes covering the diagnosis,comprehensive treatment,and follow-up visits for gastric cancer.

关键词： Chinese Society of Clinical Oncology(CSCO) Gastric cancer Diagnosis Surgery Neoadjuvant Adjuvant Radiotherapy Chemotherapy Targeted therapy Immunotherapy

基于多源数据融合技术的绿洲灌区土壤水分反演

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节水灌溉 2024年第6期 19-26页

作者：李华伟朱晓春张旭东隋喆周黎勇吴迪王叶白亮亮新疆农业大学水利与土木工程学院乌鲁木齐830052 水利部海河水利委员会科技咨询中心天津300170 沈阳农业大学水利学院沈阳110866 新疆水利水电科学研究院乌鲁木齐830049 中国灌溉排水发展中心北京100054

土壤水分是联系农业、生态和水文领域的重要环境变量,而卫星遥感是监测地表土壤水分的重要手段之一。针对微波遥感空间分辨率不足和光学遥感受云雨天气影响的问题,基于Landsat 8和MODIS光学影像、SMAP微波以及CLDAS再分析等多源数据,联... 详细信息

土壤水分是联系农业、生态和水文领域的重要环境变量,而卫星遥感是监测地表土壤水分的重要手段之一。针对微波遥感空间分辨率不足和光学遥感受云雨天气影响的问题,基于Landsat 8和MODIS光学影像、SMAP微波以及CLDAS再分析等多源数据,联合增强型自适应时空融合算法和随机森林模型对土壤水分进行定量反演,获得了绿洲灌区高时空分辨率田块尺度(30 m)土壤水分。结果表明:通过ESTARFM时空融合算法可有效获得日尺度30 m分辨率归一化植被指数(NDVI),融合后的NDVI与原始NDVI空间纹理特征一致,两者的相关系数(R)在0.85以上,均方根误差为0.05~0.08,融合效果较好。基于地表温度、NDVI、增强植被指数、叶面积指数、再分析土壤水分产品多特征参数组合下的随机森林模型反演效果最优,获得的高时空分辨率田块尺度土壤水分能够反映其时空变化,相关系数和均方根误差分别达到0.82.0.037 cm^(3)/cm^(3)。该方法可为灌区灌溉面积识别、旱情监测等提供技术支撑。

关键词：土壤水分遥感反演时空融合算法随机森林数据同化多源数据

Rotational failure analysis of spherical-cylindrical shell pressure controllers related to gas hydrate drilling investigations

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Petroleum Science 2022年第2期19卷 789-799页

作者： Cong li Jian-liang Pei Nian-Han wu Gui-Kang liu Wei Huang zhi-Xu Dai Rui-Ze wang Zhao-Fan Chen Wei-Cheng Long MOE Key Laboratory of Deep Earth Science and engineering Sichuan UniversityCollege of Water Resource and HydropowerSichuan UniversityChengdu610065China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green EnergyCollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen518060China china Pingmei Shenma Energy and Chemical Industry Group Co. Ltd.Pingdingshan467000China State Key Laboratory of Coking Coal Exploitation and Comprehensive Utilization Pingdingshan467000China Xi'an Research Institute China Coal Technology and Engineering GroupXi©an710077China

In situ pressure-preserved coring(IPP-Coring)technology is considered one of the most efficient methods for assessing ***,seal failure caused by the rotation of pressure controllers greatly affects the success of pressure *** this paper,a novel spherical-cylindrical shell pressure controller was *** finite element analysis model was used to analyze the stress distribution and deformation characteristics of the pressure controller at different rotation *** seal failure mechanism caused by the rotation of the pressure controller was *** stress deviation rate was defined to quantitatively characterize the stress *** on the test equipment designed in this laboratory,the ultimate bearing strength of the pressure controller was *** results show that the rotation of the valve cover causes an increase in the deformation on its lower ***,the specific sealing pressure in the weak zone is greatly reduced by a statistically significant amount,resulting in seal *** the valve cover rotates 5°around the major axis,the stress deviation rate is-92.6%.To prevent rotating failure of the pressure controller,it is necessary to control the rotation angle of the valve cover within 1°around the major *** results of this research can help engineers reduce failure-related accidents,provide countermeasures for pressure coring,and contribute to the exploration and evaluation of deep oil and gas resources.

关键词： Exploration of oil and gas resources Pressure coring controller Sphere flapper valve Failure modes Stress deviation rate

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强化电容去离子脱盐的吸附机理研究

环境工程 2018年第2期36卷 78-82页

作者：王志赵研姜秋俚赵勇娇何丽燕东北大学资源与土木工程学院沈阳110819 辽宁省环境监测实验中心沈阳110161 沈阳市环境科学研究院沈阳110167

采用活性炭作为电极材料,通过涂层方法制备了活性炭电极,并构建了简易的电容去离子(CDI)反应装置。从吸附热力学(吸附等温线、热力学参数等)和吸附动力学角度,对所制备的CDI用活性炭涂层电极电容去离子脱盐的吸附理论进行分析,试图揭示... 详细信息

采用活性炭作为电极材料,通过涂层方法制备了活性炭电极,并构建了简易的电容去离子(CDI)反应装置。从吸附热力学(吸附等温线、热力学参数等)和吸附动力学角度,对所制备的CDI用活性炭涂层电极电容去离子脱盐的吸附理论进行分析,试图揭示提高CDI脱盐效率的吸附机制。结果表明:Na Cl溶液在活性炭涂层电极上的吸附符合准一级动力学模型;活性炭涂层电极吸附Na Cl的过程以物理吸附为主,也进一步证明了活性炭电极对离子的吸附主要通过电场的静电引力作用,而非电化学氧化还原作用;CDI过程活性炭涂层电极电吸附Na Cl符合Langmuir吸附等温线,属于单分子层吸附。

关键词：活性炭电容去离子(CDI) 吸附热力学动力学

Significant loss of soil inorganic carbon at the continental scale

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National Science Review 2022年第2期9卷 13-20页

作者： Xiao-Dong Song Fei Yang Hua-Yong wu Jing Zhang De-Cheng li Feng liu Yu-Guo Zhao Jin-ling Yang Bing Ju Chong-Fa Cai Biao Huang Huai-Yu Long ying Lu Yue-Yu Sui Qiu-Bing wang Ke-Ning wu Feng-Rong Zhang Ming-Kui Zhang Zhou Shi Wan-Zhu Ma Gang {2. zhi-Ping Qi Qing-Rui Chang En Ci Da-Gang Yuan Yang-Zhu Zhang Jun-Ping Bai Jia-ying Chen Jie Chen Yin-Jun Chen Yun-Zhong Dong Chun-Lan Han ling li li-Ming liu Jian-Jun Pan Fu-Peng Song Fu-Jun Sun Deng-Feng wang Tian-Wei wang Xiang-Hua Wei Hong-Qi wu Xia Zhao Qing Zhou Gan-lin Zhang State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences college of Advanced Agricultural Sciences University of Chinese Academy of Sciences college of resources and Environment Huazhong Agricultural University Institute of Agricultural resources and Regional Planning Chinese Academy of Agricultural Sciences college of Natural resources and Environment South China Agricultural University Northeast Institute of Geography and Agroecology Chinese Academy of Sciences college of Land and Environment Shenyang Agricultural University School of Land Science and Technology China University of Geosciences college of Land Science and Technology China Agricultural University college of Environmental and Resource Sciences Zhejiang University Institute of Digital Agriculture Zhejiang Academy of Agricultural Sciences college of Agriculture Heilongjiang Bayi Agricultural University Tropical Crops Genetic resources Institute Chinese Academy of Tropical Agricultural Sciences college of Natural resources and Environment Northwest A & F University college of resources and Environment Southwest University college of resources Sichuan Agricultural University college of resources and Environment Hunan Agricultural University Institute of Agricultural Product Quality Standard and Testing Research Tibet Academy of Agricultural and Animal Husbandry Sciences School of Agricultural Sciences Zhengzhou University Institute of Agriculture Environment and resources Research Shanxi Academy of Agricultural Sciences college of resources and Environment Henan Agricultural University college of resources and Environment China Agricultural University college of resources and Environmental Sciences Nanjing Agricultural University college of resources and Environment Shandong Agricultural University Agricultural college Guangxi University college of Grassland and Environment Science Xinjiang Agricultural University college of Geographical Science Qinghai Normal University

Widespread soil acidification due to atmospheric acid deposition and agricultural fertilization may greatly accelerate soil carbonate dissolution and ***,to date,few studies have addressed these ***,we use meta-analysis and nationwide-survey datasets to investigate changes in soil inorganic carbon(SIC) stocks in *** observe an overall decrease in SIC stocks in topsoil(0-30 cm)(11.33 g C m-2.r-1) from the 1980 s to the 2.10 *** SIC stocks have decreased by～8.99±2.2.%(1.37±0.37 Pg C).The average SIC losses across china(0.046 Pg C yr-1) and in cropland(0.016 Pg C yr-1) account for～17.6%-2..0% of the terrestrial C sink and 57.1% of the soil organic carbon sink in cropland,*** deposition and climate change have profound influences on SIC *** estimate that～19.12.-19.47% of SIC stocks will be further lost by *** consumption of SIC may offset a large portion of global efforts aimed at ecosystem carbon sequestration,which emphasizes the importance of achieving a better understanding of the indirect coupling mechanisms of nitrogen and carbon cycling and of effective countermeasures to minimize SIC loss.

关键词： china soil inorganic carbon stocks global change carbonate soil acidification

土壤氮添加对水曲柳和蒙古栎光合限制作用的影响

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植物科学学报 2023年第4期41卷 502-512页

作者：朱凯左齐慧袁凤辉关德新吴家兵王安志张健山西农业大学资源环境学院山西太谷030801 山西农业大学资源环境学院省部共建有机旱作农业国家重点实验室(筹)太原030031 中国科学院沈阳应用生态研究所中国科学院森林生态与管理重点实验室沈阳110016 中国科学院大学北京100049

本文以试验地常年大气氮(N)沉降量(2. kg·ha^(−1)·year^(−1))为依据,设计了低度(LN,2. kg·ha^(−1)·year^(−1))、中度(MN,46 kg·ha^(−1)·year^(−1))和高度(HN,69 kg·ha^(−1)·year^(−1))3种氮添加水平以模拟大气氮沉降,以无氮添加处理为对照(CK),探究过度氮沉降对森林阔叶树种水曲柳(Fraxinus mandshurica Rupr.)和蒙古栎(Quercus mongolica *** Ledeb)的生理生态效应。结果显示:(1)两树种CO_(2.扩散性限制作用(即气孔限制lsc和叶肉限制lm)在氮添加后减弱,而后随氮量的增加先减弱后增强;其生化限制lb则在氮添加后增强,后随氮量增加先增强后减弱;(2.3种光合限制作用均在MN下达到最值,中度土壤氮添加量对植株光合的促进效应最高;(3)土壤氮添加期间植株光合能力的增强主要源于CO_(2.扩散性限制作用的减弱,而gsc变化(即lsc)为扩散性限制的主角作用因子;(4)3种光合限制作用(lsc、lm和lb)在不同生长期(7月和8月)均未表现出显著差异,表明lsc的光合主角限制“角色”无季节性差异;(5)一定范围内的土壤氮添加不会对植株的水分利用潜力产生显著影响。

关键词：气孔限制叶肉限制生化限制氮添加光合能力