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Influence of Wall Effect on Comprehensive Controllability for Ducted Fan Aircraft
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作者 Tianfu Ai Changle Xiang +2 位作者 Bin Xu Wei Fan Yibo Zhang 《Journal of Beijing Institute of Technology》 EI CAS 2020年第4期581-591,共11页
A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification... A novel coaxial ducted fan structure aircraft is proposed to enable the aircraft near vertical walls at high altitudes.The state space equation of the system can be obtained by correlation deduction and identification of the whole prototype model.Based on the duct test bench experiment and computational fluid dynamics(CFD)simulation analysis,the expressions between the different distances dWE from the rotor center of the prototype to the wall and the thrust,reaction torque,and tilting moment of the system under hovering conditions are obtained.The influence of the wall effect of the prototype is incorporated into the system model to analyze the relationship between distance dWE and the comprehensive controllability of the system.The results show that the system comprehensive controllability vector of other channels changes little with the decrease of the distance dWE,and only the controllability vector of the rolling channel increases significantly.At the same time,the tilting moment also increases significantly,which strengthens the tendency of the prototype to tilt towards the wall. 展开更多
关键词 coaxial ducted fan aircraft hovering condition wall effect tilting moment comprehensive controllability analysis
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Comprehensive Prevention and Control Technology of Vegetable Diseases and Pests in Shandong Province
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作者 Dongwen SUN Hui YU +7 位作者 Yang QIN Yujie LIN Xiaomeng QI Yuxuan CHEN Yuxin HE Xinying YAN Jia'er XU Shumei GUO 《Plant Diseases and Pests》 2024年第1期26-27,32,共3页
An in-depth research and practice has been conducted on vegetable diseases and pests in Shandong Province,and the principles of comprehensive and ecological control of diseases and pests are put forward,including agri... An in-depth research and practice has been conducted on vegetable diseases and pests in Shandong Province,and the principles of comprehensive and ecological control of diseases and pests are put forward,including agricultural control measures such as crop rotation,field cleaning,fertilizer and water management,physical control measures such as catching and killing,trapping,blocking,photoelectric energy treatment,biological control measures such as the use of natural enemies,pathogenic microorganisms,other beneficial organisms and metabolites,and scientific and rational chemical control measures.Comprehensive prevention and control not only controls vegetable diseases and pests effectively,but also protects the ecological environment. 展开更多
关键词 VEGETABLE Diseases and pests comprehensive prevention and control
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Comprehensive Control of Ecological Environment in Water Sources
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作者 Jiarong ZHANG Shuang WANG Tengfei XU 《Meteorological and Environmental Research》 CAS 2023年第3期73-77,共5页
To scientifically and effectively conduct comprehensive control of water sources to achieve water safety,the importance,main steps and plan of comprehensive control of ecological environment in water sources were anal... To scientifically and effectively conduct comprehensive control of water sources to achieve water safety,the importance,main steps and plan of comprehensive control of ecological environment in water sources were analyzed on the basis of analyzing the development and protection process of foreign water sources.The results show that for the comprehensive control of water sources,it is needed to pay attention to the accurate grasp of the current environmental quality of water sources and carefully analyze the problems in the ecological environment of water sources.Besides,it is necessary to ensure the water quality and quantity of sources,focus on the implementation of environmental remediation and ecological restoration,implement regional protection of water sources,and combine engineering and non-engineering measures to take comprehensive control of environmental problems. 展开更多
关键词 Drinking water safety Non-engineering measures Engineering measures comprehensive control
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Research Progress of Occurrence and Comprehensive Control of Fall Webworm [Hyphantria cunea( Drury) ] 被引量:7
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作者 Li Jialin Chen Jingyun Cai Ping 《Plant Diseases and Pests》 CAS 2013年第4期32-35,44,共5页
The paper summarizes the research progress of occurrence and comprehensive control of fall webworm on the aspeets of biological and ecological characteristics, assessment of risk and suitability, artificial survey Of ... The paper summarizes the research progress of occurrence and comprehensive control of fall webworm on the aspeets of biological and ecological characteristics, assessment of risk and suitability, artificial survey Of occurrence, dynamic monitoring and quarantine, comprehensive control methods and strategy. 展开更多
关键词 Fall webworm OCCURRENCE comprehensive control
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Risk Assessment and Comprehensive Control of Insect and Wild Animal Vectors in the Prevalence of Related Equine Diseases in the Specific Equine Disease-free Zone of Guangzhou Asian Games
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作者 PENG Cong LIANG Zhuo-yue +13 位作者 PENG Nan-xiu ZHANG Hai-ming HU Yong-hui XUE Hong SHEN Dan HUANG Jie KUANG Hui-yi ZHANG Hai-bing CAI Yi-fan XIE Yue-you ZHONG Jiang-guo CHEN Jin-ping YANG Yue-ping WANG Jun-wei 《Animal Husbandry and Feed Science》 CAS 2013年第2期95-100,104,共7页
[ Objective] In order to construct the specific equine disease-free zone of of the Guangzhou Asian Games, to ensure that the equestrian events of Guangzhou Asian Games be smoothly held. [Methods] The species, quantiti... [ Objective] In order to construct the specific equine disease-free zone of of the Guangzhou Asian Games, to ensure that the equestrian events of Guangzhou Asian Games be smoothly held. [Methods] The species, quantities, distribution and seasonal variations of insects and wild animals in related zones were investigated from 2008 to 2010, and the collected samples of the insects and wild animals were tested in laboratory for related equine diseases. [Results] The investigations indicated that there were some mosquitoes, flies, horseflies, punkies, ticks, bats, wild birds and wild bears in equastrianism venue and peripheral regions of disease-free zone of the Guangzhou Asian Games, the laboratory results of Japa- nese encephalitis, vesicular stomatitis, Nipah virus disease, West Nile fever, and Trypanosomiasis evansi, were all negative. According to the in- vestigations and test results, the risk assessments of insect and wild animal vectors in the prevalence of related equine diseases were made to con- firm that the risk was relatively low or very low, and comprehensive prevention and control measures with prevention as major measures and insecti- cides application and environment managements as supplementary means were made on the basis of the risk assessment conclusions. [ Conclu- sions] This research has laid a solid foundation for the successful building of the first specific equine disease-free zone in our country, ensured the smooth holding of the 16th equastdan competition in Guangzhou Asian Games. 展开更多
关键词 pecific equine disease-free zone in Guangzhou Asian Games INSECTS Wild animals Risk assessment comprehensive control measures
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Occurrence Factors and Comprehensive Prevention and Control of Chinese Rose Black Spot(Actinonema rosae)
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作者 Hu Xiangqi 《Plant Diseases and Pests》 CAS 2020年第4期6-7,12,共3页
In addition to conventional techniques,the prevention and control of Chinese rose black spot(Actinonema rosae)should be strengthened in the management of Chinese rose.The occurrence of Chinese rose black spot is close... In addition to conventional techniques,the prevention and control of Chinese rose black spot(Actinonema rosae)should be strengthened in the management of Chinese rose.The occurrence of Chinese rose black spot is closely related to plant residues,rainfall,cultivation conditions and varieties.On the basis of understanding the symptoms and occurrence regularity of Chinese rose black spot,combination measures of agricultural and chemical prevention and control should be taken. 展开更多
关键词 Chinese rose black spot(Actinonema rosae) Occurrence factors comprehensive prevention and control
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Distribution and Damage of Alien Weed Mikania micranthain in Huiyang District of China
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作者 Gao Xuhua Chen Mingzhou Huang Jian 《Plant Diseases and Pests》 CAS 2013年第3期49-53,共5页
[ Objective ] The paper was to understand distribution and damage of alien weed Mikania micramhaln in Huiyang District of China. [ Method ] The coverage, nearby water sources, surrounding plants and control status of ... [ Objective ] The paper was to understand distribution and damage of alien weed Mikania micramhaln in Huiyang District of China. [ Method ] The coverage, nearby water sources, surrounding plants and control status of M. micranthain under different habitats in Huiyang District were surveyed. [ Result] M. micrantha grew violently in the habitats of irrigation ditches, orchard, field edge and wasteland with the coverage ranging from 10% to 90%. It grew more seriously around water sources and was very likely to recur after control. The wild growth of M. micranthaln was harmful to local agriculture, forestry and fishery. The com- prehensive control measures combing artificial control, chemical control, biological control and ecological control should be adopted in different habitats. [ Conclusion] The study orovided basis for comorehensive control and invasion risk assessment of M. micranthain. 展开更多
关键词 Mikania micrantha INVESTIGATION Huiyang District comprehensive control
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Research Progress on Prevention and Control Technology of Empoasca vitis Gthe in Tea Garden
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作者 Li Xiangyang Shi Qingcai 《Plant Diseases and Pests》 CAS 2015年第6期26-29,共4页
The tea green leafhopper Empoasca vitis Gothe, one of major tea insect pests in China's Mainland, grows concealed with small size, rapid reproduction and overlapped generations, which has become the most serious i... The tea green leafhopper Empoasca vitis Gothe, one of major tea insect pests in China's Mainland, grows concealed with small size, rapid reproduction and overlapped generations, which has become the most serious insect pest in tea garden. This paper described the morphological features, damage modes and occur- rence characteristics of E. vitis, and preliminarily summarized the main control methods in recent years. Therefore, from pollution-free and green control perspec- tive, controlling population quantity of E. vitis safely and effectively and reducing the yield loss of tea has become a hot issue in prevention and control of insect pests in tea garden. The paper provided a reference in green comprehensive prevention of insect pests in tea garden. 展开更多
关键词 Empoasca vitis Gothe Prevention methods comprehensive control
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Occurrence and Control of Pear Rust in Eastern Hebei Province
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作者 Longfei LI Lijuan GAO +2 位作者 Jintao XU Minghui JI Baofeng HAO 《Plant Diseases and Pests》 CAS 2022年第1期13-14,共2页
In recent years, pear rust sometimes occurs in eastern Hebei area, resulting in early defoliation, fruit abscission and loss of fruit commodity value. In this paper, the incidence symptoms, regularity and causes of pe... In recent years, pear rust sometimes occurs in eastern Hebei area, resulting in early defoliation, fruit abscission and loss of fruit commodity value. In this paper, the incidence symptoms, regularity and causes of pear rust are summarized, and the comprehensive prevention and control measures of pear rust in eastern Hebei are put forward. 展开更多
关键词 PEAR RUST Incidence regularity comprehensive prevention and control
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Occurrence Dynamics and Countermeasure of Wheat Crown Rot in Weifang City
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作者 Hongping TIAN Guocai LU +3 位作者 Xiuhua WEI Hongxia TIAN Miao ZHANG Fujun LI 《Plant Diseases and Pests》 CAS 2022年第5期10-11,共2页
Wheat crown rot was first found in Weifang City in 2015,and now has become a major disease of wheat,showing an aggravating trend year by year.The author investigated the occurrence area and characteristics of wheat cr... Wheat crown rot was first found in Weifang City in 2015,and now has become a major disease of wheat,showing an aggravating trend year by year.The author investigated the occurrence area and characteristics of wheat crown rot in Weifang City over the past 5 years,and analyzed the causes of the disease.The disease was mainly related to variety resistance and farming system.According to the occurrence regularity of the disease,a set of comprehensive control measures were put forward. 展开更多
关键词 Wheat crown rot Occurrence characteristics Influencing factors comprehensive prevention and control
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Occurrence and Prevention and Control Progresses of Chilades pandava in Cycas spp.
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作者 Liu Chunhong Cai Ping 《Plant Diseases and Pests》 CAS 2018年第1期1-5,16,共6页
The occurrence and comprehensive prevention and control progresses of Chilades pandava in Cycas spp. are summarized from the aspects of classification and geographic distribution, ecological characteristics, damage a... The occurrence and comprehensive prevention and control progresses of Chilades pandava in Cycas spp. are summarized from the aspects of classification and geographic distribution, ecological characteristics, damage and development rules, and comprehensive prevention and control technology, in order to provide a reference for further prevention and control against C. pandava in Cycas spp. 展开更多
关键词 Chilades pandava OCCURRENCE comprehensive prevention and control
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Integrated Prevention and Control Technology of Major Diseases and Insect Pests of Strawberry
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作者 Yang Lei Yang Li +2 位作者 Li Li Du Runsheng Dong Hui 《Plant Diseases and Pests》 CAS 2020年第2期31-34,共4页
In order to effectively deal with the problems of diseases and insect pests in the growth process of strawberry and to improve the quality and yield of strawberry,the main diseases and insect pests in strawberry culti... In order to effectively deal with the problems of diseases and insect pests in the growth process of strawberry and to improve the quality and yield of strawberry,the main diseases and insect pests in strawberry cultivation such as powdery mildew,gray mold,anthracnose,red stele root rot,calcium deficiency,salt or fertilizer damage,aphids,red spiders,thrips,grubs,etc.and their identification methods were analyzed.The comprehensive pollution-free prevention and control techniques of these pests and diseases were explored,in order to provide technical guidance for high quality,efficient and harmless production of strawberry. 展开更多
关键词 STRAWBERRY Diseases and insect pests comprehensive prevention and control
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Prevalence Characteristics of Rice Black-streaked Dwarf Virus Disease and Continuous Control Strategies
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作者 Deyou LIU Yangang LIU +8 位作者 Lijuan LIU Xiaomei CUI Zhaotang SHEN Jinqian LIU Xiugang YU Zhouliang WANG Shengfeng ZHANG Qingquan MU Xiushan ZHAO 《Asian Agricultural Research》 2021年第6期54-58,共5页
Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivati... Through summarizing the prevalence characteristics of rice black-streaked dwarf virus disease(RBSDVD)in Linyi City of Shandong Province,this paper analyzed its prevalence is related to changes in farming and cultivation systems,the increase in the population of venomous Laodelphax striatellus Fallén and its own migration and spread,the poor disease resistance of cultivated varieties,and inadequate time of prevention and control.Besides,based on the practice of local control,it came up with some comprehensive control measures including strengthening monitoring,early warning and forecasting,planting resistant(tolerant)rice varieties according to local conditions,appropriately delaying the sowing(planting)period,supplemented by insect nets to cover seedlings,and making scientific use of chemical control.It is expected to provide a reference for the prevention and control of RBSDVD. 展开更多
关键词 Rice black-streaked dwarf virus disease(RBSDVD) CHARACTERISTICS Prevalence reasons Monitoring and early warning forecast comprehensive prevention and control measures
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Comprehensive Optimal Control on Seismic Response of a Single-Tower Self-Anchored Suspension Bridge 被引量:1
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作者 WANG Hao LI Aiqun JIAO Changke 《Wuhan University Journal of Natural Sciences》 CAS 2011年第1期55-63,共9页
Earthquake may cause severe damage to all kinds of bridge such as the falling down of the girder; therefore,effective measures should be employed to control the seismic displacement. In this paper,the method of compre... Earthquake may cause severe damage to all kinds of bridge such as the falling down of the girder; therefore,effective measures should be employed to control the seismic displacement. In this paper,the method of comprehensive optimal control,com-bined with analytic hierarchy process,is employed to investigate the seismic response control of the Nanjing Jiangxinzhou Bridge,which is a single-tower self-anchored suspension bridge (SSSB). Also,3-dimensional nonlinear seismic response analyses are con-ducted. Three types of practical connection measures for seismic response control of SSSB are investigated,and the optimal pa-rameters of the connection devices are achieved by this method. Results show that both the elastic connection devices and the damp-ers with rational parameters can reduce the seismic displacement of the bridge effectively,but the elastic connection devices will in-crease the seismic force of the tower. When all factors are consid-ered,the optimal measure is by using the elastic connection devices and the dampers together. These results can provide references for seismic response control of SSSBs. 展开更多
关键词 self-anchored suspension bridge (SSSB) seismic response comprehensive optimal control single tower analytic hierarchy process (AHP) method
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Robust adaptive fault-tolerant control of a tandem coaxial ducted fan aircraft with actuator saturation 被引量:14
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作者 Xiaoliang WANG Changle XIANG +1 位作者 Homayoun NAJJARAN Bin XU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2018年第6期1298-1310,共13页
This paper is concerned with the robust adaptive fault-tolerant control of a tandem coaxial ducted fan aircraft under system uncertainty, mismatched disturbance, and actuator saturation.For the proposed aircraft, comp... This paper is concerned with the robust adaptive fault-tolerant control of a tandem coaxial ducted fan aircraft under system uncertainty, mismatched disturbance, and actuator saturation.For the proposed aircraft, comprehensive controllability analysis is performed to evaluate the controllability of each state as well as the margin to reject mismatched disturbance without any knowledge of the controller. Mismatched disturbance attenuation is ensured through a structured Hinfinity controller tuned by a non-smooth optimization algorithm. Embedded with the H-infinity controller, an adaptive control law is proposed in order to mitigate matched system uncertainty and actuator fault. Input saturation is also considered by the modified reference model. Numerical simulation of the novel ducted fan aircraft is provided to illustrate the effectiveness of the proposed method. The simulation results reveal that the proposed adaptive controller achieves better transient response and more robust performance than classic Model Reference Adaptive Control(MRAC) method, even with serious actuator saturation. 展开更多
关键词 comprehensive controllability Ducted fan aircraft Fault-tolerant Input saturation Robust adaptive control
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Reflections and Explorations on the Decremented Regulation of Construction Land in the New Beijing City Master Planning
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作者 Chang Qing Xu Qinzheng +2 位作者 Yang Chun Wang Shan Qian Fang 《China City Planning Review》 CSCD 2018年第2期25-35,共11页
Construction land use has always been a key point for the planning department to practice national transformation strategy. In the new round of compilation of Beijing City Master Plan, the management of construction l... Construction land use has always been a key point for the planning department to practice national transformation strategy. In the new round of compilation of Beijing City Master Plan, the management of construction land use is under the rigid restriction of the bearing capacity of resources and the environment. Setting the upper-limit of the population size, a general strategy of decremented development of urban-rural construction land has been put forward, in order to realize a transition from quantitative expansion planning to qualitative upgrading planning. By "decremented development," "decremented" means a more rigid bottom-line restriction, and "development" means a more scientific allocation of resources. From the master planning level, the new Beijing City Master Plan establishes a comprehensive control framework and restrictive index system from perspectives including land use scale, construction scale, space boundary, urban and rural structure, land use structure, and cross-boundary collaboration; and in practice, it promotes strict management methods by setting up a dismantle-construction land ratio, dismantle-construction building area ratio, employment and residence land ratio, and "two lines and three districts," which is an exploration on the planning management method of construction land use that is stock-based and decremented master planning. Considering that decremented development is a major reform and a special challenge to planning implementation, the Beijing City Master Plan carries out explorations in terms of the planning management method, land policy, jurisdiction division, assessment and supervision, etc. 展开更多
关键词 master plan decremented development urban and rural construction land comprehensive control BEIJING
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