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Testing method and distribution characteristics of spatial pesticide spraying deposition quality balance for unmanned aerial vehicle

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International Journal of Agricultural and Biological Engineering 2018年第2期11卷 18-26页

作者： Changling Wang Xiongkui He Xiaonan Wang Zhichong Wang Shilin Wang Longlong Li Jane Bonds Andreas Herbst Zhiguo Wang co.lege of Science China Agricultural UniversityBeijing 100193China Bonds co.sulting group LLC Panama City Florida 32408USA Institute for Application Techniques in Plant protection Julius Kühn-Institute(JKI)Federal Research Centre for Cultivated PlantsMesseweg 11/12 D-38104 BraunschweigGermany Quanfeng Aviation Plant protection Technology co. Ltd.Anyang 455001China

In order to explore the spatial pesticide spraying deposition distribution,the downwash flow field characteristics for unmanned aerial vehicle(UAV)pesticide application with accurate flight height and velocity and the relationship of these two aspects,a novel measurement method was proposed in this paper.A model‘3WQF80-10’single-rotor diesel UAV was tested using this method in wheat field and the effects of flight direction,flight parameters and crosswind on the distribution of spatial spraying deposition quality balance(SSDQB)and the downwash flow field distribution were researched.A cuboid aluminum sampling frame of spatial spraying deposition quality balance(SFSSDQB)with monofilament wires was made for co.lecting the droplets in four directions,and a set of multi-channel micro-meteorology measurement system(MMMS)was applied for measuring the downwash wind speed in three ***,BeiDou Navigation Satellite System(BNSS)was used for co.trolling and reco.ding the working height,velocity and track of this model of single-rotor *** results showed the distribution of the spatial spray deposition and the downwash flow field of UAV co.ld be measured effectively at exact flight height and velocity via this *** the average wind speed was 0.9 m/s,the average temperature was 31.5℃ and the average relative humidity was 34.1%,and the average distribution ratios of spraying deposition for model‘3WQF80-10’UAV on the upwind part,the top part,the downwind part and the bottom part were 4.4%,2.3%,50.4%and 43.7%,*** flight directions of forward and backward had an impact on droplet deposition distribution and the working effect of flying backwards,with 60%of deposition ratio of the bottom part of the SFSSDQB,was better than flying *** was a linear negative co.relation between the co.fficient of variation(CV)of the bottom part and the flight height and the co.fficient of determination was 0.9178,which means that the deposition distribution

关键词： unmanned aerial vehicle(UAV) spatial spraying deposition distribution downwind airflow flow field

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Reliability testing and reliability analysis of the over-load protective relay

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 475-480页

作者： ZHAO Jing-ying CHEN Hong-jian LIU Guo-jin ZHANG Yong WU Pin-hua Postdoctoral Research Work Station Delixi Group Co. Ltd Wenzhou 325604 China Electrieal Apparatus Institute Hebei University of Technology Tianjin 300130 China

The over-load protective relay is widely used directly affects the safe running of a motor. The reliability for motor protection. The reliability of the over-load protective relay testing and reliability analysis of the over-load protective relay is an important way to improve the reliability of products. In this paper, the reliability test method of the over-load protective relay is studied, and the reliability tests of the typical products are carried out on a reliability tester developed by authors. In terms of the testing results, the reliability analysis is finished. The failure reasons are found and the measures are put forward to improve the reliability of the products.

关键词： Over-load protective relay Protective success analysis ratio Sampling and checking plan Reliability testing Reliability analysis

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Characteristics of rural domestic sewage discharge and their driving mechanisms: evidence from the Northern Region, China

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Frontiers of environmental Science & Engineering 2024年第7期18卷 47-58页

作者： Jianguo Liu Ziyu Zhou Pengyu Li Zixuan Wang Ying Yan Xuezheng Yu Wenkai Li Tianlong Zheng Yingnan Cao Wenjun Wu Wenqian Cai Zhining Shi Junxin Liu Key Laboratory of environmental Pollution co.trol and Remediation at Universities of Inner Mongolia Autonomous Region College of Resources and Environmental EngineeringInner Mongolia University of TechnologyHohhot 010051China State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China SCEGC No.12 co.struction Engineering group co. Ltd.Ankang 725000China State environmental protection Key Laboratory of environmental Planning and Policy Simulation Chinese Academy of Environmental PlanningBeijing 100041China Technical Centre for Soil Agriculture and Rural Ecology and EnvironmentMinistry of Ecology and EnvironmentBeijing 100012China Sustainable Infrastructure and Resource Management(SIRM) UniSA STEMUniversity of South AustraliaSouth AustraliaMawson LakesSA 5095Australia

The traits of rural domestic sewage emission are unclear,negatively affecting rural domestic sewage treatment and sewage *** study used data from the Seco.d National Pollution Source Census Bulletin to establish a data *** spatial distribution characteristics and main factors influencing rural sewage discharge in the Northern Region were studied using spatial autoco.relation analysis and structural *** findings demonstrated that(l)a significant Spearman co.relation between drainage water volume(DwV),chemical oxygen demand(co.),ammonia nitrogen(NH_(3)-N),total nitrogen(TN),and total phosphorus(TP)and that the co.relation co.fficients between DWV and co.,NH,-N,TNand TP were 0.87**,1.0**,0.99**,0.99**,respectively;(2)rural sewage discharge showed spatial autoco.relation,and rural domestic sewage discharge in the districts and co.nties with an administration was significantly higher than in the surrounding areas;and(3)social development was the main driver rural domestic sewage changes(path co.fficient was 0.407**),and the main factors influencing rural domestic sewage discharge were the urbanization rate,years of education,and population age *** study obtained the spatial variation law and clarified the main influencing factors of rural domestic sewage to provide data support and a theoretical basis for subsequent rural sewage co.lection and *** of the Inner Mongolia Autonomous Region in northern China as a typical case,provides a theoretical foundation for scientific decision-making on rural domestic sewage treatment at the national and regional levels and offers new perspectives for managing pollutants.

关键词： Rural domestic sewage Emission characteristics Spatial autoco.relation analysis Influencing factors

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A co.parative Study of Supervised Classification Methods for Investigating Landslide Evolution in the Mianyuan River Basin,China

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Journal of Earth Science 2023年第2期34卷 316-329页

作者： Yujie Long Weile Li Runqiu Huang Qiang Xu Bin Yu Gang Liu State Key Laboratory of Geohazard Prevention and Geoenvironment protection Chengdu University of TechnologyChengdu 610059China Sichuan Metallurgical Geological Survey and Design group co. LtdChengdu 610081China co.lege of Earth Sciences Chengdu University of TechnologyChengdu 610059China

The Ms8.0 Wenchuan earthquake of 2008 dramatically changed the terrain surface and caused long-term increases in the scale and frequency of landslides and debris *** changing trend of landslides in the earthquake-affected area over the decade since the earthquake remains largely *** this study,we were able to address this issue using supervised classification methods and multitemporal remote sensing images to study landslide evolution in the worst-affected area(Mianyuan River Basin)over a period of ten *** images were processed using the maximum likelihood method and random forest algorithm to automatically map landslide occurrence from 2007 to *** principal findings are as follows:(1)when co.pared with visual image analysis,the random forest algorithm had a good average accuracy rate of 87%for landslide identification;(2)postevent landslide occurrence has generally decreased with time,but heavy monsoonal seasons have caused temporary spikes in activity;and(3)the postearthquake landslide activity in the Mianyuan River Basin can be divided into a strong activity period(2008 to 2011),medium activity period(2012 to 2016),and weak activity period(post 2017).Landslide activity remains above the prequake level,with damaging events being rare but co.tinuing to ***-term remote sensing and on-site monitoring are required to understand the evolution of landslide activity after strong earthquakes.

关键词： Wenchuan earthquake Mianyuan River Basin automatic detection evolutionary trend maximum likelihood method random forest algorithm engineering geology

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Distribution characteristics and environmental risk assessment following metal(loid)s pollution incidents at Southwest China mining site

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Transactions of Nonferrous Metals Society of China 2022年第12期32卷 4062-4075页

作者： Zhen-xing WANG Yun-jun YU Tian-tian YE Jiang-chi FEI Xin-yu SONG Jian-wei PENG Yao-yu ZHOU Hong-hua WU South China Institute of environmental Sciences Ministry of Ecology and EnvironmentGuangzhou 510530China State environmental protection Key Laboratory of Water environmental Simulation and Pollution co.trol Guangzhou 510655China co.lege of Resources and Environment Hunan Agricultural UniversityChangsha 410128China Guangxi Hezhou Dongrong Industrial Investment group co. Ltd.Hezhou 542899China

Limited information is available on long-term effects of metal(loid)s pollution incidents. Here, we analyze the distribution characteristics and quantification of elements in the Southwest China Keda mining site, which is one of the most populated sites and enables human health and eco.ogical risk assessments of elemental pollution. The results on modified degree of co.tamination indicated that the soil and sediment were highly co.taminated near Dahu *** health risk of children was almost 2.5 times that of adults in surface water, and 7.1 times in soil, ***, Tl and As were the main health risk co.tributors in surface water and soil, respectively, and As posed the highest eco.ogical risk both in soil and sediment. These results indicated the potential impact of toxic metal(loid)s on the health of residents and environment. Hence, more scientific attention and proper management need to be paid to this environmental challenge in the future.

关键词： thallium arsenic mining site eco.ogical risk health risk

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Microcalorimetric Investigation of Influence of Fungicide SYP-L190 on Growth Metabolism of Tetrahyrnena therrnophila and Bacillus thuringiensis

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Chinese Journal of Chemistry 2007年第12期25卷 1798-1801页

作者：李会荣库宗军覃彩芹张忠海刘义 co.lege of Chemistry & Molecular Sciences Wuhan University Wuhan Hubei 430072 China Department of Chemistry Xiaogan University Xiaogan Hubei 432100 China Wuhan Tobacco.(group) co. ltd. Wuhan Hubei 430051 China

Flumorph （SYP-L190） is a new systemic fungicide with good protective, curative and antisporulant activities but no phytotoxicity to certain plants. Its performance on the environmental eco.ystem is unknown. Tetrahymena thermophila and Bacillus thuringiensis are two of biological indicators for the aquatic and soil environmental eco.ystem respectively. Microcalorimetric technique based on the heat output was applied to evaluate the influence of fungicide flumorph （SYP-L190） on the two microorganisms. The thermogenic curves and co.responding thermodynamic and thermokinetic parameters were obtained. SYP-L190 at a co.centration of 50-100 μg·mL^-1 had 5%- 10% inhibitory ratios aganist Tetrahymena thermophila and was used as a protection reagent, while at a co.centration of 100-200 μg·mL^-1 SYP-L190 had 10%-20% inhibitory ratios and was used as a therapy reagent. The metabolic thermogenic curves of Bacillus thuringiensis co.tained bacterial growth phase and sporulation phase. The SYP-L190 at a co.centration of 0-200 μg·mL^-1 had no influence on bacterial growth phase, but led to a little lag of the sporulation phase with a co.stant heat output. Hormesis was obviously observed in present study.

关键词： microcalorimetry SYP-L190 Bacillus thuringiensis Tetrahymena thermophila

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Deep learning-based intelligent management for sewage treatment plants

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Journal of Central South University 2022年第5期29卷 1537-1552页

作者： WAN Ke-yi DU Bo-xin WANG Jian-hui GUO Zhi-wei FENG Dong GAO Xu SHEN Yu YU Ke-ping National Research Base of Intelligent Manufacturing Service Chongqing Technology and Business UniversityChongqing 400067China Chongqing South-to-Thais environmental protection Technology Research Institute co. Ltd.Chongqing 400069China Chongqing Sino French environmental Excellence Research&Development Center co. Ltd.Chongqing 400042China Global Information and Teleco.munication Institute Waseda UniversityTokyoJapan

It is generally believed that intelligent management for sewage treatment plants(STPs) is essential to the sustainable engineering of future smart *** co.e of management lies in the precise prediction of daily volumes of *** generation of sewage is the result of multiple factors from the whole social *** by strong process abstraction ability,data mining techniques have been viewed as promising prediction methods to realize intelligent STP ***,existing data mining-based methods for this purpose just focus on a single factor such as an eco.omical or meteorological factor and ignore their co.laborative *** address this challenge,a deep learning-based intelligent management mechanism for STPs is proposed,to predict business ***,the grey relation algorithm(GRA) and gated recursive unit network(GRU) are co.bined into a prediction model(GRAGRU).The GRA is utilized to select the factors that have a significant impact on the sewage business volume,and the GRU is set up to output the prediction *** co.ducted a large number of experiments to verify the efficiency of the proposed GRA-GRU model.

关键词： deep learning intelligent management sewage treatment plants grey relation algorithm gated recursive unit

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Study of Oil-Bearing Drill Cuttings Cleaning and De-Oiling Treatment Method for Shale Gas Reservoirs

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Energy Engineering 2023年第8期120卷 1899-1917页

作者： Jialuo Rong Shuixiang Xie Huijing Geng Hao Hu Shanfa Tang Yuanpeng Cheng School of Petroleum Engineering Yangtze UniversityWuhan430100China Key Laboratory of Drilling and Production Engineering for Oil and Gas Wuhan430100China State Key Laboratory of Petroleum and Petrochemical Pollutant co.trol and Treatment Beijing102206China China National Petroleum group Safety and environmental protection Technology Research Institute co. Ltd.Beijing102206China Underground Gas Storage Branch CNPCBeijing100101China

Due to its extensive use in shale gas exploration and development,oil-based drilling fluids generate large amounts of oil-bearing drill cuttings during the drilling *** large amount of oil-bearing drill cuttings generated during the drilling process can lead to serious seco.dary *** this study,a wetting agent FSC-6 with good hydrophobic and oleophobic properties was synthesized to co.struct an efficient oil removal *** the first time,the mechanism of this system was analyzed by using the theory of adhesion function,interfacial tension and *** the same time,a co.bined aco.stic-chemical treatment process was applied to the wastewater and slag generated after the cleaning of the oil-bearing drill *** experimental results show that the application of this pollution-free technology can effectively solve the environmental pollution and resource reco.ery problems of oil-bearing drill *** meets the standard of drilling chips with oil co.tent less than 2%in SY/T7422-2018“Oil-based drilling fluid drilling chips treatment system for oil and gas drilling equipment”.

关键词： Oil-bearing drill cuttings fluorocarbon surfactants chemical cleaning ultrasonic cleaning oil co.tent rate

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Study on attrition of spherical-shaped Mo/HZSM-5 catalyst for methane dehydro-aromatization in a gas–solid fluidized bed

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Chinese Journal of Chemical Engineering 2021年第10期34卷 172-183页

作者： Xinzhuang Zhang Yunda Han Dapeng Li Zhanguo Zhang Xiaoxun Ma School of Chemical Engineering Northwest UniversityXi’an 710069China Research Institute of Shaanxi Yanchang Petroleum(group)co. Ltd.Xi’an 710065China Chemical Engineering Research Center of the Ministry of Education(MOE)for Advanced Use Technology of Shanbei Energy Xi’an 710069China Shaanxi Research Center of Engineering Technology for Clean co.l co.version Xi’an 710069China co.laborative Innovation Center for Development of Energy and Chemical Industry in Northern Shaanxi Xi’an 710069China International Scientific and Technological co.peration Base of the Ministry of Science and Technology(MOST)for Clean Utilization of Hydrocarbon Resources Xi’an 710069China Hydrocarbon High-efficiency Utilization Technology Research Center of Shaanxi Yanchang Petroleum(group)co. Ltd.Xi’an 710065China Key Laboratory on Resources Chemicals and Materials Shenyang University of Chemical TechnologyShenyang 110142China Longdong University Qingyang 745000China

As a potential methane efficient co.version process,non-oxidative aromatization of methane in fluidized bed requires a catalyst with good attrition resistance,especially in the states of high temperature,longtime rapid movement and chemical *** evaluation methods for attrition resistance,such as ASTM D5757 and Jet Cup test,are targeted for fresh catalysts at ambient temperature,which cannot well reflect the real *** this study,spherical-shaped Mo/HZSM-5 catalyst prepared by dipping and spray drying was placed in a self-made apparatus for attrition testing,in which the catalyst attrition under different system temperatures,running time and process factors was investigated with percent mass loss(PML),particle size-mass distribution(PSMD)and scanning electron microsco.e(SEM).Carbon deposition on the catalyst before and after activation,aromatization and regeneration was analyzed by thermogravimetry(TG),and the attrited catalysts were evaluated for methane dehydro-aromatization(MDA).The results show that the surface abrasion and body breakage of catalyst particles occur co.tinuously,with the increase of system temperature and running time,and make the PML rise *** process factors of activation,aromatization and regeneration can cause the catalyst attrition and carbon deposits,which broaden the PSMD in varying degrees,and the carbon-substances on catalysts greatly improve their attrition resistance at high *** attrition has a certain influence on its catalytic performance,and the main reasons point to particle breakage and fine powder escape.

关键词： Attrition Mo/HZSM-5 Fluidized-bed Catalyst activation Methane dehydro-aromatization

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Wear mechanism and life prediction of the ripper in a 9-m-diameter shield machine tunneling project of the Beijing new airport line in a sand-pebble stratum

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Deep Underground Science and Engineering 2022年第1期1卷 65-76页

作者： Hua Jiang Jiachen Zhu Xiaoyan Zhang Jinxun Zhang Hongliang Li Lingfeng Meng Department of Urban Underground Space School of Mechanics and Civil EngineeringChina University of Mining and TechnologyBeijingChina Post-Doctoral Research Center Beijing Urban Construction Group Co.Ltd.BeijingChina

Tool wear is a noteworthy problem in the process of shield tunneling,and the degree of wear varies with *** sand-pebble strata in Beijing are typically mechanically ***,many subways are buried wholly or partially in sand-pebble *** the Beijing New Airport line tunneling project as research background,this study evaluated the wear characteristics of the multico.figuration rippers of a 9-m-diameter spoke-type shield tunneling machine in a sand-pebble *** wear values of five ripper teeth and ripper flanks were analyzed based on field-measured data from the Beijing New Airport line *** the analytical results show,the wear value generally increases as the installation radius enlarges with the rise of cutting trace *** wear of the 190-rippers was divided into five categories:pedestal wear,ripper teeth co.lapse,uniform wear,ripper teeth falling off and ripper flank *** wear of the ripper teeth and ripper flank wear were the two abrasion types of the *** teeth of the 155-rippers mostly maintained their cutting capacity under the protection of the 190-rippers.A wear prediction model of linear fitting field data was developed for a 190-ripper face to obtain the optimum shield driving distance in the sand-pebble *** average wear co.fficients of the 190-ripper before and after replacement matched well,being 0.045 and 0.066 mm/km,*** results of this study provide a theoretical reference for tool wear prediction in shield co.struction under similar geological co.ditions.

关键词： 9-m-diameter shield long-distance shield driving optimum driving distance sand-pebble stratum tool wear wear prediction model

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