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| 1 | Performances evaluation of four typical unmanned aerial vehicles used for pesticide application in China显示文摘In recent years,unmanned aerial vehicles(UAVs)for plant protection have achieved rapid development in China.In order to test and evaluate the performances of pesticides application and development status of UAVs in China,four typical UAV models were selected to test the spraying coverage,penetrability,droplets density and the work efficiency.The results showed that the deposition and spraying liquid coverage were inconsistent both in lateral and longitudinal direction.Under the condition of the similar amount of spray volume and operation parameters,the volume median diameter(VMD)of the droplet was negatively correlated with the coverage density.The failure of the UAVs for plant protection mainly took up on the blockage of nozzle,transfusion tube and the liquid pump.The failure rate of UAVs took up 3.73%-4.36%of the total working time.The operation of UAVs during ground service took up 50%of the total working time,the preparation work took up 10%,and the route planning took up around 10%,while net operation time only took up around 30%.On the whole,the high efficiency of UAV was not fully achieved;the daily operated area was not in a satisfactory level now.The spraying performances of UAVs still need further improvement. | Wang Shilin Song Jianli He Xiongkui Song Le Wang Xiaonan Wang Changling Wang Zhichong Ling Yun | 2017 | International Journal of Agricultural and Biological Engineering2017，10，4： | 25 |
| 2 | Testing method and distribution characteristics of spatial pesticide spraying deposition quality balance for unmanned aerial vehicle显示文摘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 collecting 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 directions.Besides,BeiDou Navigation Satellite System(BNSS)was used for controlling and recording the working height,velocity and track of this model of single-rotor UAV.The results showed the distribution of the spatial spray deposition and the downwash flow field of UAV could be measured effectively at exact flight height and velocity via this method.When 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%,respectively.The 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 forward.There was a linear negative correlation between the coefficient of variation(CV)of the bottom part and the flight height and the coefficient of determination was 0.9178,which means that the deposition distribution becomes more uniform with the increase of height.Additionally,there was a linear positive correlation between weighted mean deposition rate and crosswind speed and the coefficient of determination was 0.9684,which shows the deposition distribution gets more concentrated towards the downwind part with the rise of crosswind speed.Therefore,according to the results of tests of downwash airflow speed,it is shown that regardless of the flight direction and height and the crosswind,all these factors influence the droplet deposition distribution via weakening the intensity of the downwash airflow field in the direction perpendicular to the ground.The results can provide valuable information for the research of UAV pesticide application techniques and the establishment of the standard of spraying deposition and drift tests of UAV in crop field. | Changling Wang Xiongkui He Xiaonan Wang Zhichong Wang Shilin Wang Longlong Li Jane Bonds Andreas Herbst Zhiguo Wang | 2018 | International Journal of Agricultural and Biological Engineering2018，11，2： | 14 |
| 3 | MPC-based energy management with adaptive Markov-chain prediction for a dual-mode hybrid electric vehicle显示文摘The and energy to management strategy battery is state an important part of a hybrid electrical vehicle design.It is used to improve various fuel economy sustain a proper of charge an by controlling control the power components is while satisfying to constraints and driving demands.However,achieving optimal and performance challenging due the nonlinearities of the hybrid powertrain,conflicting vehicle the time varying constraints,the dilemma capable in which controller control complexity and real-time capability are generally objectives.In this paper,a of real-time cascaded complies strategy is proposed for a dual-mode hybrid electric that considers controller based nonlinearities based the system model and with all time-varying with constraints.sampling The strategy consists of a supervisory controller on a non-linear predictive control short(MPC)sampling a long time with future strategy interval and a coordinating on linear model predictive based control with a time interval to deal different load dynamics of the system.The Additionally,a novel data methodology using adaptive Markov chains to predict demand is introduced.predictive future information is used to improve controller cycles performance.conducted.The The proposed is implemented validity on a real test-bed approach and experimental trials using economy unknown is driving are results other demonstrate the of the proposed and show that fuel significantly improved compared with methods. | XIANG ChangLe DING Feng WANG WeiDa HE Wei QI YunLong | 2017 | Science China(Technological Sciences)2017，60，5： | 11 |
| 4 | HUMAN-IMITATING INTELLIGENT CONTROL AND TRIPLE INVERTED-PENDULUM显示文摘HUMAN-IMITATINGINTELLIGENTCONTROLANDTRIPLEINVERTED-PENDULUM￥ZhangMinglian;HaoJiankang;HeWeidong(305,DepartmentofAutomaticCont... | Zhang Minglian Hao Jiankang He Weidong (305, Department of Automatic Control, Beijing University of Aeronautics and Astronautics, Beijing, China, 100083)Sun Changling(Department of Automation, Tsinghua University, Beijing, China, 100084) | 1996 | Chinese Journal of Aeronautics1996，9，2： | 4 |
| 5 | Spray drift characteristics test of unmanned aerial vehicle spray unit under wind tunnel conditions显示文摘Since the 2010s,unmanned aerial vehicle(UAV)sprayer was applied more and more widely for low-volume aerial pesticides spraying operations in China.However,droplets from the UAV sprayer have a higher drift risk due to more fine droplets sprayed and a higher flight height than ground sprayers.Study on UAV spray drift has been a new hot spot within the field of pesticide application technology.Most of previous studies used direct field methods for spray drift,but the meteorological conditions in field were unstable and uncontrollable,and drift research under an actual operation state in wind tunnel has not been reported.Therefore,25 treatments of wind tunnel measurements and droplets spectrum tests of 10 models of nozzles were conducted to explore the influence factor on spray drift characteristics of UAV chemicals application in this study.A spray unit with a rotor of UAV was innovatively installed in wind tunnel,and the airstream from the wind tunnel was regarded as the relative moving natural wind to simulate the flight status.The airborne and the sediment spray drift was measured to study the effects of the nozzle type and size(flat fan,hollow cone and air-inclusion nozzles),flight speed,adjuvant(DRS-60,Y-20079,MF and G-611)and meteorological parameters(20°C&40%,20°C&80%,30°C&40%and 30°C&60%).The drift potential(DP)and the drift potential reduction percentage(DPRP)in vertical and horizontal directions were obtained for each test.Both nozzle type and size had an impact on the spray drift potential obviously by affecting the droplet size and the ratio of fine droplets,and the regression linear models between DPRPV/DPRPH and DV50,V75 were established(R2=0.934/0.925).Flight speed also had a significant effect on the spray drift characteristics,and reducing the flight speed could increase the DP effectively.Adding spray adjuvants could affect the DP under experimental meteorological parameters,and the anti-drift performance ranked in the order of DRS-60>MF>Y-20079>G-611.Recommendations were proposed in order to reduce the spray drift for UAV sprayer’s operation.These findings can contribute to provide guidelines and technical support for the wind tunnel spray drift tests of UAV and the field operation regulation of unmanned aerial PPP application. | Changling Wang Aijun Zeng Xiongkui He Jianli Song Andreas Herbst Wanlin Gao | 2020 | International Journal of Agricultural and Biological Engineering2020，13，3： | 3 |
| 6 | A CRISPR/Cas12a-empowered surface plasmon resonance platform for rapid and specific diagnosis of the Omicron variant of SARS-CoV-2显示文摘The outbreak of the COVID-19 pandemic was partially due to the challenge of identifying asymptomatic and presymptomatic carriers of the virus,and thus highlights a strong motivation for diagnostics with high sensitivity that can be rapidly deployed.On the other hand,several concerning SARS-CoV-2 variants,including Omicron,are required to be identified as soon as the samples are identified as‘positive’.Unfortunately,a traditional PCR test does not allow their specific identification.Herein,for the first time,we have developed MOPCS(Methodologies of Photonic CRISPR Sensing),which combines an optical sensing technology-surface plasmon resonance(SPR)with the‘gene scissors’clustered regularly interspaced short palindromic repeat(CRISPR)technique to achieve both high sensitivity and specificity when it comes to measurement of viral variants.MOPCS is a low-cost,CRISPR/Cas12a-systemempowered SPR gene-detecting platform that can analyze viral RNA,without the need for amplification,within 38 min from sample input to results output,and achieve a limit of detection of 15 fM.MOPCS achieves a highly sensitive analysis of SARS-CoV-2,and mutations appear in variants B.1.617.2(Delta),B.1.1.529(Omicron)and BA.1(a subtype of Omicron).This platform was also used to analyze some recently collected patient samples from a local outbreak in China,identified by the Centers for Disease Control and Prevention.This innovative CRISPR-empowered SPR platform will further contribute to the fast,sensitive and accurate detection of target nucleic acid sequences with single-base mutations. | Zhi Chen Jingfeng Li Tianzhong Li Taojian Fan Changle Meng Chaozhou Li Jianlong Kang Luxiao Chai Yabin Hao Yuxuan Tang Omar AAl-Hartomy Swelm Wageh Abdullah GAl-Sehemi Zhiguang Luo Jiangtian Yu Yonghong Shao Defa Li Shuai Feng William J.Liu Yaqing He Xiaopeng Ma Zhongjian Xie Han Zhang | 2022 | National Science Review2022，9，8： | 3 |
| 7 | Drift potential of UAV with adjuvants in aerial applications显示文摘The reduction of pesticide aerial spraying drift is still one of the major challenges in modern agriculture.The aim of this study was to evaluate the drift potential of different types of unmanned aerial vehicle(UAV)and adjuvant products for reducing spray drift in aerial applications.Three types of UAV(3WQF120-12 and 3CD-15 fuel oil powered single-rotor UAV and HY-B-15L battery powered single-rotor UAV)were selected in this study with regular application parameters to compare each spray drift,and 3WQF120-12 fuel oil powered UAV was selected to quantify spray drift of 6 adjuvants dissolved in water under field conditions.Solutions were marked with brillant sulfoflavin dye(BSF)at 0.1%.Petri dishes and rotary impactors were used to collect airborne and sediment drift,respectively.Drift deposits were evaluated by spectrophotometry in order to quantify deposits.The results showed that when the flight height was 1.5-2.0 m above the crop at the flight speed of 4-5 m/s and the average wind speed of 1.63-1.73 m/s,3WQF120-12 fuel oil powered UAV had lower drift potential than the other two types;DV0.5 and percentage of droplets with diameter≤75μm had very significant effects on spray drift percentage(p=0.01);the risk of drift in agricultural spraying could be significantly decreased not only by reducing the percentage of fine droplets but also by changing droplet spectra.Compared to water,Silwet DRS-60,ASFA+B,T1602,Break-thru Vibrant,QF-LY and Tmax could reduce by 65%,62%,59%,46%,42%,and 19%spray drift,respectively.when water without adjuvants were sprayed,90%of drift droplets were located within a range of 10.1 m of the target area while with 0.8%Silwet DRS-60 adjuvant in water,the distance was shortened to 6.4 m. | Xiaonan Wang Xiongkui He Jianli Song Zhichong Wang Changling Wang Shilin Wang Ruochen Wu Yanhua Meng | 2018 | International Journal of Agricultural and Biological Engineering2018，11，5： | 3 |
| 8 | Mineralogical and microfabric characteristics of magnetite in the Wuyang Precambrian BIFs, southern North China Craton: Implications for genesis and depositional processes of the associated BIFs显示文摘 | Hongzhong Li Mingguo Zhai Lianchang Zhang Zhijun Yang Argyrios Kapsiotis Yongzhang Zhou Junguo He Changle Wang Jin Liang | 2014 | Journal of Asian Earth Sciences2014，，： | 1 |
| 9 | The Variation of Microbial(Methanotroph)Communities in Marine Sediments Due to Aerobic Oxidation of Hydrocarbons显示文摘Methanotrophs in marine sediments and overlying water attenuate the emissions of methane into the atmosphere and thus play an important role for the global cycle of this greenhouse gas.However,gas released from natural hydrocarbon seeps are not pure methane but commonly mixed hydrocarbons.Currently,how methanotrophic bacteria behave in the co-presence of methane and heavier hydrocarbons remains unknown.In this paper,the bacteria were cultured aerobically in fresh sediment samples(collected from Bohai Bay in eastern China)at 28℃under the atmospheres of pure methane and methane+ethane+propane mixed gas,respec-tively.The prevailing terrigenous n-alkanes and fatty acids in the original sediment samples varied consistently after incubations,confirming the proceeding of aerobic bacterial activities.The real-time quantitative PCR assay and sequencing of the 16S rRNA and particulate methane monooxygenase(pmoA)genes revealed the changes of microbe communities to a methanotroph-dominating structure after incubations.Particularly,after incubations the family Methylococcaceae(typeⅠmethanotrophs)became dominant with proportions higher than 40%,whereas Methylocystaceae(typeⅡmethanotrophs)nearly disappeared in all incubated samples.More-over,the species of methanotrophs from the samples treated with pure methane were dominated by Methylobacter luteus,whereas Methylobacter whittenburyi took the predominant proportion in the samples treated with mixed gas.The phenomenon suggests that some methanotrophs may also utilize ethane and propane.Collectively,this study may help to gain a better understanding of the ef-fects and contributions of microbial activities in marine hydrocarbon seep ecosystems. | LI Jing LIU Changling WU Nengyou HE Xingliang HAO Xiluo LI Feng CHEN Ye MENG Qingguo | 2021 | Journal of Ocean University of China2021，20，3： | 1 |
| 10 | Optimization of hot air drying process for tiger nut and analysis of fatty acid composition of tiger nut oil显示文摘Hot air temperature,hot air humidity,and hot wind speed were selected as independent variables of quadratic orthogonal rotation combination test design through single factor test.Drying time,energy consumption,chromatism value,luminosity value,hardness,rehydration ratio,and other indexes of the product were used as the response value of the test.Response surface methodology(RSM)was used to analyze the effects of independent variables on the quality of tiger nut(Cyperus esculentus L.),and the process parameters were combined and optimized.The results show that the suitable technological conditions for hot air drying of tiger nut are as follows:hot air temperature of 63.15°C,hot air humidity of 44.92%,hot air wind speed of 2.48 m/s.Under these conditions,the product has the advantages of the short drying cycle,low energy consumption,good color and luster,low hardness and good rehydration performance.The fatty acid composition and content of tiger nut oil were determined by gas chromatography.The fatty acid composition and content of tiger nut oil were compared with those of soybean oil,olive oil,rapeseed oil and sesame oil,the results show that among the saturated fatty acids in tiger nut oil,palm oil had the highest content of 11.172%,which was between soybean oil and olive oil.The main composition of unsaturated fatty acids in tiger nut oil is oleic acid,with a content of 77.605%,which is 3.6 times higher than that of soybean oil,and even higher than that of olive oil. | He Li Xiaoxiao Niu Jiajun Chai Changle Guo Yihao Sun Jianhua Li Chunying Li | 2021 | International Journal of Agricultural and Biological Engineering2021，14，6： | 1 |
| 11 | Pozzolanic reactions of six principal clay minerals: Activation, reactivity assessments and technological effects显示文摘 | Changling He Bjarne Osbaeck Emil Makovicky | 1995 | Cement and Concrete Research1995，，8： | 1 |
| 12 | Pozzolanic reactions of six principal clay minerals:activation,reactivity assessments and technological effects显示文摘 | Changling He Bjarne Osback Emil Makovicky | 1995 | Cement and Concrete Research1995，25，8： | 1 |
| 13 | 南海珠江口盆地天然气水合物特征显示文摘2013年中国在南海珠江口(PRM)盆地东部开展天然气水合物钻探并成功获取天然气水合物样品。我们对其中一块水合物样品进行了实验室分析研究。研究发现水合物样品呈结核状,沉积物主要为粉砂质砂和粘土。拉曼光谱和X射线衍射的结果表明,水合物为典型的I型结构(sI),甲烷的大笼和小笼占有率分别为99.5%和91.4%,通过热动力学计算,该样品水合指数为5.90。水合物气体以甲烷气体为主(〉99.9%),含有少量的乙烷(0.04%)和丙烷(0.01%)。同位素分析表明PRM地区水合物中的甲烷气体为典型的生物成因气。 | Changling Liu Qingguo Meng Xingliang He 尉建功 | 2017 | 海洋地质2017，0，3： | 0 |
| 14 | VERIFICATION-ORIENTED ROBDD OPERATION DESIGN显示文摘This paper describes a new BDD(Binary Decision Diagram) that use SCOAP value for its path. Based on analysis of BDD and input variables, variable ordering and reducing algorithms for BDD operation that are constructed by circuits description of netlist are proposed. Further, several bench nark circuits are shown to verify the efficient methods. | He Xinhua(Armoured Force Engineering Institute, Beijing 100072)Lu Changling Wei Daozheng(Institute of Computing Technology, Academj’a Sinica, Beijing 100080) | 1996 | Journal of Electronics(China)1996，13，1： | 0 |
| 15 | Dysfunctional resting-state EEG microstate correlated with the severity of cigarette exposure in nicotine addiction显示文摘Dear editor,Nicotine is a significant cause of severe physical and psychiatric disorders.Evidence suggests that smokers have poorer global cognitive functioning in later life,as well as lower average scores in several cognitive domains,including cognitive flexibility and memory [1]. | Yan CHENG Junjie BU Nan LI Jian LI Huixing GOU Shinan SUN Chang LIU Zida JIN Changle HE Chuan FAN Chialun LIU Xiaochu ZHANG | 2020 | Science China(Information Sciences)2020，63，7： | 0 |
| 16 | 锆富氢新材料中发现高于70 K的高温超导性质显示文摘氢是周期表里质量最轻的元素,早期理论预测氢在超高压条件可以呈现固体金属态,根据BCS电声耦合理论推测金属氢可能具有高温超导特性.然而实现纯氢的金属化需要很高的压力,技术复杂极具挑战.富氢化合物可以对氢提供“化学预压缩”,有可能在较低压力实现以氢为主的金属化和超导,目前实验上已经在硫、稀土和碱土金属等富氢化物材料发现高温超导现象.本文作者运用自行研发的先进的超高压和激光加热一体化的极端条件集成技术,在~220 GPa、2000 K的高压高温条件下成功合成了高质量的锆富氢新化合物,并在锆富氢化合物中发现高压在位诱导的临界转变温度(T;)高达71 K的超导现象,这是首次在4d过渡金属氢化物发现高温超导. | Changling Zhang Xin He Zhiwen Li Sijia Zhang Shaomin Feng Xiancheng Wang Richeng Yu Changqing Jin | 2022 | Science Bulletin2022，67，9： | 0 |
| 17 | Dynamic spreading characteristics of droplet impinging soybean leaves显示文摘The study on the deposition efficiency of pesticide droplets on soybean leaves can provide the basis for reducing pesticide quantity and increasing pesticide efficiency during the application of soybean plant protection machinery.The movement behavior of droplet impinges on the plant leaf surface is affected by many factors,among which the most important and the easiest to adjust are spray droplet size and impingement velocity.By changing the droplet size and impact velocity and using Fluent simulation software,the pesticide droplet hitting the soybean leaf surface was simulated and a test platform was established to verify the simulation results.The conclusions are as follows:The longitudinal roughness of soybean leaves is higher than the transverse roughness,the longitudinal pressure of soybean leaves is higher than the transverse pressure during the impact process,and the velocity of droplet spreading along the longitudinal is lower than that of spreading along the transverse;although soybean leaf surface has high adhesion,droplet losses still exist when droplet impact velocity is relatively high.The maximum spreading diameter of the droplet increases first and then decreases with the increase of impact velocity.At the same time,the maximum spreading diameter of droplet increases with the increase of particle size.The droplet deposition was best at 1.34 m/s impact velocity and 985μm particle size.This conclusion can provide optimal operation parameters for soybean plant protection operation which can be used to guide soybean plant protection operation,improve control effect,reduce quantity and increase efficiency. | He Li Xiaoxiao Niu Li Ding Ali Shahid Tahir Changle Guo Jiajun Chai Kaifei Zhang Shangshang Cheng Yiqiu Zhao Yahui Zhang Yigao Xu Zengqiang Shang | 2021 | International Journal of Agricultural and Biological Engineering2021，14，3： | 0 |
| 18 | Superconductivity above 70 K observed in lutetium polyhydrides显示文摘The binary polyhydrides of heavy rare earth lutetium that shares a similar valence electron configuration to lanthanum have been experimentally discovered to be superconductive.The lutetium polyhydrides were successfully synthesized at high pressure and high temperature conditions using a diamond anvil cell in combinations with the in-situ high pressure laser heating technique.The resistance measurements as a function of temperature were performed at the same pressure of synthesis in order to study the transitions of superconductivity(SC).The superconducting transition with a maximum onset temperature(Tc)71 K was observed at pressure of 218 GPa in the experiments.The Tcdecreased to 65 K when pressure was at 181 GPa.From the evolution of SC at applied magnetic fields,the upper critical field at zero temperatureμ0Hc2(0)was obtained to be~36 T.The in-situ high pressure X-ray diffraction experiments imply that the high TcSC should arise from the Lu4H23phase with Pm3n symmetry that forms a new type of hydrogen cage framework different from those reported for previous light rare earth polyhydride superconductors. | Zhiwen Li Xin He Changling Zhang Ke Lu Baosen Min Jun Zhang Sijia Zhang Jianfa Zhao Luchuan Shi Yi Peng Shaomin Feng Zheng Deng Jing Song Qingqing Liu Xiancheng Wang Richeng Yu Luhong Wang Yingzhe Li Jay D.Bass Vitali Prakapenka Stella Chariton Haozhe Liu Changqing Jin | 2023 | Science China(Physics,Mechanics & Astronomy)2023，66，6： | 0 |
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