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Rotor cross-tilt optimization for yaw control improvement of multi-rotor eVTOL aircraft

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Chinese Journal of Aeronautics 2024年第3期37卷 153-167页

作者： Xufei YAN Ye YUAN Yanqin ZHAO Renliang CHEN Zhejiang Lab Hangzhou 311100China Department of Aerospace Engineering Swansea UniversitySwanseaWales SA28PPUK National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Manned multi-rotor electric Vertical Takeoff and Landing(eVTOL)aircraft is prone to actuator saturation due to its weak yaw control *** address this inherent problem,a rotor cross-tilt configuration is applied in this paper,with an optimization method proposed to improve the overall control efficiency of the ***,a flight dynamics model of a 500-kg manned multi-rotor eVTOL aircraft is *** accuracy of the co-axial rotor model is verified using a single arm test bench,and the accuracy of the flight dynamics model is verified by the flight test ***,an optimization method is designed based on the flight dynamics model to calculate an optimal rotor cross-tilt mounting angle,which not only improves the yaw control efficiency,but also basically maintains the efficiency of other control *** ideal rotor cross-tilt mounting angle for the prototype is determined by comprehensively considering the optimal results with different payloads,forward flight speeds,and rotor mounting angle ***,the feasibility of the rotor cross-tilt mounting angle is proved by analyzing the control derivatives of the flight dynamics model,the test data of a ground three Degree-of-Freedom(3DOF)platform,and the actual flight data of the *** results show that a fixed rotor cross-tilt mounting angle can achieve ideal yaw control effectiveness,improving yaw angle tracking and hold ability,increasing endurance time,and achieving good yaw control performance with different payloads and forward speeds.

关键词： Multi-rotor eVTOL control efficiency Flight dynamics model Cross-tilt optimization Endurance time

Effect of aerial spray adjuvant applying on the efficiency of small unmanned aerial vehicle for wheat aphids control

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 46-53页

作者： Yanhua Meng Yubin Lan Guiying Mei Yongwang Guo Jianli Song Zhiguo Wang College of Engineering South China Agricultural UniversityGuangzhou 510642China National Center for International Collaboration Research on Precision Agricultural Aviation Pesticide Spraying Technology Guangzhou 510642China School of Environmental Sciences University of GuelphGuelphONN1G 2W1Canada The National Agro-Tech Extension and Service Center Beijing 100125China College of Science China Agricultural UniversityBeijing 100193China Key Laboratory of Aviation Plant Protection Ministry of Agriculture and Rural AffairsBeijing 100193China Anyang Quanfeng Biological Technology Co. LtdAnyang 455000China

Small unmanned aerial vehicles(UAVs)have been widely used in different aspects of modern farming management,including pest and disease control in China in recent *** this study,the spray performance of a small plant protection UAV at low volume spray was evaluated by adjusting the pesticide dosage and adding aerial spraying *** deposition,droplet density,coverage,control effect and pesticide residue from field trials were *** addition,the residue and control effect of UAV spray were compared to manual knapsack at high volume *** results showed that,the adjuvant applying improved the efficiency of UAV ***,the adjuvant applying reduced the dosage of imidacloprid by 20%.However,there was no significant difference on initial residue between UAV spray and knapsack ***,plant protection UAV spraying pesticide by adding appropriate adjuvant showed the ability of improving the pesticide effectiveness by improving the control efficiency,reducing the pesticide dosage and residue.

关键词： unmanned aerial vehicle(UAV) aerial spraying adjuvant deposition control efficiency pesticide residue wheat aphid

Modeling and analysis of moving-mass actuated stratospheric airship

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High Technology Letters 2013年第2期19卷 145-149页

作者：周革 Chen Li Dong Qi Department of Aeronautics and Astronautics Shanghai Jiaotong University Mudanjiang Medical University

A moving-mass control method is introduced to stratospheric airship for its special working condition of low atmospheric density and low *** dynamic equation of airship is derived by using the Newton-Euler method and the mechanism of attitude control by moving masses is *** the passive gliding of airship by the moving masses is given based on the theory of glider,and attitude control capability between moving mass and elevator is compared at different *** results show that the motion of masses changes the gravity center of the airship system,which makes the inertia tensor and the gravity moment ***,the aerodynamic angles are generated,which results in the change of aerodynamic *** efficiency of moving masses is independent of *** the moving-mass control has the advantage over the aerodynamic surfaces at low airspeed.

关键词： stratospheric airship moving masses attitude control gliding control efficiency

Antagonistic Endophytic Bacteria Isolated from Different Growth Stages of Cotton for the control of Cotton Verticillium wilt

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Agricultural Science & Technology 2012年第4期13卷 778-783页

作者：周燚杨廷宪杨佩王斌先孙正祥长江大学农学院湖北荆州434025

[Objective] This study aimed to investigate the combined control effects of endophytic bacteria at different growth stages against cotton Verticfllium wilt and pro- vide a new strategy for the biocontrol of other soil-borne diseases. [Method] Endophytic bacteria with high resistance against Verticillium wilt were isolated from seedling, squaring and boll-setting cotton vascular, respectively. Their 16S rDNA se- quences were detected for comparative analysis. Three biocontrol strains were se- lected and identified, whose colonization roles in cotton plants were explored. The control efficiency was determined with indoor and field experiments. [Result] Accord- ing to the 16S rDNA sequence homology, the three strains were identified as Paeni- bacillus polyrnyxa YUPP-8, Paenibacillus xylanilyticus YUPP-1 and Bacillus subtilis YUPP-2, respectively. Results of colonization assessment showed that three strains all could be successfully colonized in cotton vascular. However, application amount had a positive effect on the number of colonized biocontrol bacteria in cotton, strain YUPP-8 had the largest number of colonized biocontrol bacteria in seedling period, strain YUPP-1 had the largest number of colonized biocontrol bacteria in squaring period, and strain YUPP-2 had the largest number of colonized biocontrol bacteria in boll-setting period. Indoor pot experiment showed that cotton plants in combined bio- control bacteria treatment group were not infected in flowing period, while Verticillium wilt morbidity rate of cotton treated with single strain in seedling period were 6.7% （YUPP-8）, 6.7% （YUPP-1） and 13.3% （YUPP-2）; however, Verticillium wilt morbidity rate wilt of the control reached 80%. Field experiment conducted during 2010-2011 showed that the combined application of three strains had better effect than separate application; specifically, Verticillium wilt morbidity rate and disease index of cotton in boll-setting period with combined application of three strain

关键词： Cotton Verticillium dahliae Paenibacillus polymyxa Paenibacillus xylanilyticus Bacillus subtilis Colonization control efficiency

Screening of Chemical control for Potato Blight

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Plant Diseases and Pests 2015年第2期6卷 16-18页

作者： Chen Chunyan Wang Chaohai Chen Yuzhang Liang Zhengjuan Wang Shengnan Wang Song Bijie Institute of Agricultural Sciences

To screen chemicals for controlling potato blight effectively, randomized block experiment was adopted, the control efficiency of five chemicals for Carbendazim, Metalaxyl, Dithane mancozeb, Curzate, Cymoxanil mancozeb was explored. The results showed that the efficiency of Metalaxyl was much better than that of other conventional chemicals in controlling potato blight, up to 70.59% ; the mean control efficiency of Curzate and Cymoxanil mancozeb was 68.76% and 67.05% ; the control efficiency of Carbendazim was lower, 55.76%. Big and middle tuber rate, tuber weight per hole, plot yield, unit area yield of potatoes in Metalaxyl treatment were the highest, 78.05%, 437.24 g/hole, 34.0 kg/21.6 m2 and 15 748.61 kg/hm2, 49.12% higher than the control yield. The indexes of potatoes in Cymoxanil mancozeb treatment were the second highest, 73.33%, 385.31 g/hole, 32.8 kg/21.6 m2 and 15 192.78 kg/hm2, 43.86% higher than the control yield.

关键词： Potato blight Chemical control efficiency Yield increase rate

Chemical Application for Prevention and control of Post-harvest Citrus Diseases

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Plant Diseases and Pests 2015年第1期6卷 25-27页

作者： Xu Weisong Tan Yaohua Zhou Zhenbiao Shao Mei Agricultural Pest Precaution and Management Center of Guangdong Province Agricultural Bureau of Gaoyao City

[ Objective] To study the control efficiency of 45% Prochloraz amines ME and 500 g/L Triabendazole SC for the post-harvest diseases of citrus fruits, and the economic and efficient dosage and application techniques. [ Method] Carry out prevention and control test of common post-harvest diseases of tangerines, such as anthracnose, green mold and penicillium disease. [ Result] The experiment agent 45% Prochloraz amines ME showed excellent effect in controlling post- harvest anthracnose of citrus fruits, the 45t^-day control efficiency was above 73% ; the 45ts-day control efficiency of 45% Prochloras amines ME and 500 g/L Tri- abendazole SC for green mold and penicillium disease was above 72%. [ Conclusion] 45% Prochloraz amines ME and 500 g/L Triabendazole SC are two ideal agents for preventing and controlling post-harvest diseases and safeguarding quality of citrus fruits.

关键词： Triabendazole Prochloraz amines Citrus Fruit disease control efficiency

Field efficiency Trial of Microbial Fertilizer against Eggplant Verticillium Wilt

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Plant Diseases and Pests 2016年第1期7卷 19-21页

作者： Zhang Dongmei Gao Zhenjiang Gao Wa Wang Qi Zhang Dongxu Liu Mingxing Baotou Institute of Agricultural Sciences Baotou 014060China Plant Ecological Engineering Graduate School China Agricultural UniversityBeijing 00094China

The control effect of microbial fertilizer on eggplant verticillium wilt was studied through investigation of disease index and diseased plant rate. The reiults showed that the disease index and diseased plant rate of eggplant verticillium wilt were the lowest in the plots with substrate treatment and root-irrigation treatnent. The control effects in the plots with substrate treatment were higher than those in the plots with only root irrigation treatment. Moreover, higher concentration of microbial fertilizer resulted in better control effect and higher yield. Thus, the microbial fertilizer had a broad application prospect.

关键词： Microbial fertilizer Eggplant Verticillium wilt Disease index control efficiency

Effects of Radix Curcumae Fungicides on Tobacco Brown Spot and Yield of Flue-cured Tobacco Leaves

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Agricultural Science & Technology 2016年第7期17卷 1736-1737,1748页

作者：田兰梅桂勇龙章富罗定棋四川省烟草公司泸州市公司四川泸州646400 四川大学生命科学学院四川成都610064

This study aimed to investigate the effects of Radix Curcumae fungicides on tobacco brown spot and yield of flue-cured tobacco leaves. Through field experi- ments, control efficiency of Radix Curcumae fungicides against tobacco brown spot was investigated. The results showed that the average control efficiency of 400-fold, 600-fold and 800-fold Radix Curcumae fungicides against tobacco brown spot reached 37.83%, 34.09% and 24.32%, respectively. This study could provide the ba- sis for screening and application of plant-derived fungicides against tobacco brown spot.

关键词： Curcumae extract Tobacco brown spot control efficiency Effect

Physiological Effect and Quality Influences of Hedyotis diffusae Extract on Tobacco Infected by TMV

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Plant Diseases and Pests 2010年第4期1卷 12-15页

作者：白海群刘子仪崔德强云南省烟草公司普洱市公司云南普洱665000

The extract from Hedyotis diffusae was used to treat tobacco plants infected by TMV before and after incidence. The effect of the changes of some physiological and biochemical indices related with the virus-resistance in tobacco leaves on tobacco quality ware determined. The resuits showed that H. diffusae extract could remarkably increase the total phenol content in tobacco leaves ,strength the activity of phenylalanine ammonialyase （ PAL） , improve the membrane permeability and tobacco quality. Prevention treatment was better than therapy treatment. In conclusion, H. diffusae extract could induce plants to produce disease resistance and strength tha antiviral capability of tobacco against TMV.

关键词： Hedyotis diffusae Willd. Extract TMV control efficiency Physiologic~ effect China