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Aerodynamic/control integrated optimization method for unpowered high-speed vehicle configuration design
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作者 Xin PAN Linlin WANG +2 位作者 Li LI Lulu JIANG Gang CHEN 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第7期153-167,共15页
The unpowered high-speed vehicle experiences a significant coupling between the disciplines of aerodynamics and control due to its characteristics of high flight speed and extensive maneuverability within large airspa... The unpowered high-speed vehicle experiences a significant coupling between the disciplines of aerodynamics and control due to its characteristics of high flight speed and extensive maneuverability within large airspace.The conventional aircraft conceptual design process follows a sequential design approach,and there is an artificial separation between the disciplines of aerodynamics and control,neglecting the coupling effects arising from their interaction.As a result,this design process often requires extensive iterations over long periods when applied to high-speed vehicles,and may not be able to effectively achieve the desired design objectives.To enhance the overall performance and design efficiency of high-speed vehicles,this study integrates the concept of Active Control Technology(ACT)from modern aircraft into the philosophy of aerodynamic/control integrated optimization.Two integrated optimization strategies,with differences in coupling granularity,have been developed.Subsequently,these strategies are put into action on a biconical vehicle that operates at Mach 5.The results reveal that the comprehensive performance of the synthesis optimal model derived from the aerodynamic/control integrated optimization strategy is improved by 31.76%and 28.29%respectively compared to the base model under high-speed conditions,demonstrating the feasibility and effectiveness of the method and optimization strategies employed.Moreover,in comparison to the single-stage strategy,the multi-stage strategy takes into deeper consideration the impact of control capacity.As a result,the control performance of the synthesis opti-mal model derived from the multi-stage strategy improves by 13.99%,whereas the single-stage strategy only achieves a 5.79%improvement.This method enables a fruitful interaction between aerodynamic configuration design and control system design,leading to enhanced overall performance and design efficiency.Furthermore,it improves the controllability of high-speed vehicles,mitigating the risk of mission failure resulting from an ineffective control system. 展开更多
关键词 Aerodynamic/control integrated Optimization MDO High-speed vehicle Shape Optimization controllability
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Integrated Prevention and Control Technology for Coffee Leaf Rust in Yunnan Province
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作者 Xingfei FU Guiping LI Faguang HU 《Asian Agricultural Research》 2024年第11期25-28,共4页
This paper investigates the damage symptoms and occurrence regularity related to coffee leaf rust,and proposes a comprehensive prevention and control strategy grounded in the principle of prioritizing prevention and i... This paper investigates the damage symptoms and occurrence regularity related to coffee leaf rust,and proposes a comprehensive prevention and control strategy grounded in the principle of prioritizing prevention and implementing integrated prevention and control.This strategy encompasses the cultivation of rust-resistant varieties,the implementation of agricultural practices,the application of chemical interventions,the utilization of hyperparasitic fungi,and the protection and utilization of natural enemies.The paper further outlines the necessary requirements for effective prevention and control,emphasizing the importance of enhancing responsibility implementation,fostering systematic prevention and control measures,enhancing guidance services,and increasing publicity and guidance.The aim is to offer technical guidance for the integrated prevention and control of coffee leaf rust in Yunnan Province. 展开更多
关键词 Coffee leaf rust disease Damage symptoms Occurrence regularity integrated prevention and control Yunnan Province
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Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view
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作者 Wei Wang Jiaqi Liu +2 位作者 Shiyao Lin Baokui Geng Zhongjiao Shi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第5期211-221,共11页
In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated... In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown missiles.The threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV constraint.The boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular FOV.Then,the nonlinear adaptive controller is designed to estimate the changing aerodynamic parameters.The generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking accuracy.Furthermore,the command filters are used to solve the"differential expansion"problem during the backstepping design.The Lyapunov theory is used to prove the stability of the overall closed-loop IEGC system.Finally,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets. 展开更多
关键词 integrated estimation guidance and control Circular field-of-view Time-varying integral barrier Lyapunov function Command filtered backstepping control Nonlinear adaptive control Extended state observer
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Integrated Green Prevention and Control Techniques for Kiwifruit Canker Disease in "Guichang" Kiwifruit in Xiuwen County, Guizhou Province
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作者 Miao LI Xian WEI +4 位作者 Rong WU Shouying TANG Suran WAN Liqian JIANG Song BAI 《Agricultural Biotechnology》 CAS 2023年第5期30-34,42,共6页
Kiwifruit canker disease seriously affects the yield and quality of"Guichang"kiwifruit in Xiuwen County,Guizhou Province.In order to scientifically,safely,greenly and efficiently prevent and control the dise... Kiwifruit canker disease seriously affects the yield and quality of"Guichang"kiwifruit in Xiuwen County,Guizhou Province.In order to scientifically,safely,greenly and efficiently prevent and control the disease,theory was combined with prevention and control techniques to optimize existing prevention and control techniques,so as to improve the production yield and quality of kiwifruit.Specifically,biocontrol strains targeting local kiwifruit canker disease were screened,and reduced and mixed use of agrochemicals with improved efficiency was studied;and the effects and application techniques of disease resistance inducers and bioorganic fertilizers in inducing systemic disease resistance in kiwifruit trees were explored,and finally,an integrated green prevention and control scheme for kiwifruit canker disease that is suitable for kiwifruit production areas in Guizhou Province and has strong operability was proposed.This study provides technical support for green,efficient,standardized production technical services and sustainable and healthy development of kiwifruit industry. 展开更多
关键词 KIWI Pseudomonas Syringae pv.actinidiae(Psa) SYMPTOM Occurrence rule integrated control
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Coupled Dynamics and Integrated Control for Position and Attitude Motions of Spacecraft:A Survey
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作者 Feng Zhang Guangren Duan 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第12期2187-2208,共22页
Inspired by the integrated guidance and control design for endo-atmospheric aircraft,the integrated position and attitude control of spacecraft has attracted increasing attention and gradually induced a wide variety o... Inspired by the integrated guidance and control design for endo-atmospheric aircraft,the integrated position and attitude control of spacecraft has attracted increasing attention and gradually induced a wide variety of study results in last over two decades,fully incorporating control requirements and actuator characteristics of space missions.This paper presents a novel and comprehensive survey to the coupled position and attitude motions of spacecraft from the perspective of dynamics and control.To this end,a systematic analysis is firstly conducted in details to show the position and attitude mutual couplings of spacecraft.Particularly,in terms of the time discrepancy between spacecraft position and attitude motions,space missions can be categorized into two types:space proximity operation and space orbital maneuver.Based on this classification,the studies on the coupled dynamic modeling and the integrated control design for position and attitude motions of spacecraft are sequentially summarized and analyzed.On the one hand,various coupled position and dynamic formulations of spacecraft based on various mathematical tools are reviewed and compared from five aspects,including mission applicability,modeling simplicity,physical clearance,information matching and expansibility.On the other hand,the development of the integrated position and attitude control of spacecraft is analyzed for two space missions,and especially,five distinctive development trends are captured for space operation missions.Finally,insightful prospects on future development of the integrated position and attitude control technology of spacecraft are proposed,pointing out current primary technical issues and possible feasible solutions. 展开更多
关键词 Coupled position and attitude dynamic modeling integrated position and attitude control position and attitude coupling analysis SPACECRAFT space missions
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Reversible Semi-Fragile Watermarking Technique for Integrity Control of Relational Database
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作者 Ali Hamadou Abdoul Aziz Issaka Hassane +1 位作者 Lanciné Camara Harouna Naroua 《Engineering(科研)》 2024年第9期309-323,共15页
Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differ... Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differentiate between legal and malicious modifications. In this paper, we introduce a novel lossless semi-fragile scheme based on prediction-error expansion for content protection of relational database. In the proposed method, all attributes in a database relation are first classified according to their sensitivity to legitimate updates. Then, the watermark is embedded by expanding the prediction error of the two least significant digits of securely selected attributes. At watermark extraction, the proposed method has the ability to fully restore the original data while detecting and localizing tampering. The applicability of our method is demonstrated theoretically and experimentally. 展开更多
关键词 Semi-Fragile Watermarking Integrity control REVERSIBILITY Prediction-Error Expansion
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Integrated Guidance and Control of Homing Missiles Against Ground Fixed Targets 被引量:23
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作者 侯明哲 段广仁 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2008年第2期162-168,共7页
This paper presents a scheme of integrated guidance and autopilot design for homing missiles against ground fixed targets. An integrated guidance and control model in the pitch plane is formulated and further changed ... This paper presents a scheme of integrated guidance and autopilot design for homing missiles against ground fixed targets. An integrated guidance and control model in the pitch plane is formulated and further changed into a normal form by nonlinear coordinate transformation. By adopting the sliding mode control approach, an adaptive nonlinear control law of the system is designed so that the missile can hit the target accurately with a desired impact attitude angle. The stability analysis of the closed-loop system is also conducted. The numerical simulation has confirmed the usefulness of the proposed design scheme. 展开更多
关键词 integrated guidance and control pitch plane ground fixed target nonlinear adaptive
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APPLICATION OF HYBRID AERO-ENGINE MODEL FOR INTEGRATED FLIGHT/PROPULSION OPTIMAL CONTROL 被引量:4
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作者 王健康 张海波 +1 位作者 孙健国 李永进 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期16-24,共9页
The real-time capability of integrated flight/propulsion optimal control (IFPOC) is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gr... The real-time capability of integrated flight/propulsion optimal control (IFPOC) is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gramming (SQP). Firstly, a steady-state hybrid aero-engine model is designed in the whole flight envelope with a dramatic enhancement of real-time capability. Secondly, the aero-engine performance seeking control including the maximum thrust mode and the minimum fuel-consumption mode is performed by SQP. Finally, digital simu- lations for cruise and accelerating flight are carried out. Results show that the proposed method improves real- time capability considerably with satisfactory effectiveness of optimization. 展开更多
关键词 integrated flight/propulsion optimal control AERO-ENGINE hybrid model performance seeking con- trol sequential quadratic programming
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Study on Integrated Control against Oriental Fruit Fly[Bactrocera dorsalis(Hendel)] in Guava Orchard
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作者 雷艳梅 廖冬晴 +1 位作者 黄树长 谢荔元 《Plant Diseases and Pests》 CAS 2011年第2期47-50,共4页
[ Objective ] The paper was to explore the damage, occurrence pattern and integrated control methods of oriental fruit fly [ Bactrocera dorsalis ( Hen- del) ] in Nanning region of Guangxi Province. [ Method ] Using ... [ Objective ] The paper was to explore the damage, occurrence pattern and integrated control methods of oriental fruit fly [ Bactrocera dorsalis ( Hen- del) ] in Nanning region of Guangxi Province. [ Method ] Using fixed system survey method, with fruit fly attractants as the materials, the occurrence dynamic of oriental fruit fly adult in guava orchard was investigated. The control effects of the methods such as fruit fly attractants, fruit bagging, cleaning park to pick up fallen fruit and timely spraying pesticide against the pest were also studied. [ Result] Oriental fruit fly had two damage peak periods in Nanning region of Guangxi Prov- ince (May to June, August to September). Through the integrated control measures of trapping agent for male flies, timely spraying, fruit bagging and cleaning park to pick up fallen fruit, the population density in guava orchard dropped significantly. The fruit damage rates of guava in research base were only 6.67% -7.33% during the peak period of oriental fruit fly in June 2008, while they were 90.53% -98.00% in control area, obtaining good control effect against the pest. [ Con- dttalon ] The method used in the study preliminarily restored the yield losses of guava, which also provided basis for the preparation of overall strategy against orien- tal fruit fly in the region. 展开更多
关键词 GUAVA Oriental fruit fly integrated control
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A Novel Integrated Stability Control Based on Differential Braking and Active Steering for Four-axle Trucks 被引量:8
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作者 Buyang Zhang Changfu Zong +2 位作者 Guoying Chen Yanjun Huang Ting Xu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2019年第1期174-194,共21页
Di erential braking and active steering have already been integrated to overcome their shortcomings. However, existing research mainly focuses on two-axle vehicles and controllers are mostly designed to use one contro... Di erential braking and active steering have already been integrated to overcome their shortcomings. However, existing research mainly focuses on two-axle vehicles and controllers are mostly designed to use one control method to improve the other. Moreover, many experiments are needed to improve the robustness; therefore, these control methods are underutilized. This paper proposes an integrated control system specially designed for multi-axle vehicles, in which the desired lateral force and yaw moment of vehicles are determined by the sliding mode control algorithm. The output of the sliding mode control is distributed to the suitable wheels based on the abilities and potentials of the two control methods. Moreover, in this method, fewer experiments are needed, and the robustness and simultaneity are both guaranteed. To simplify the optimization system and to improve the computation speed, seven simple optimization subsystems are designed for the determination of control outputs on each wheel. The simulation results show that the proposed controller obviously enhances the stability of multi-axle trucks. The system improves 68% of the safe velocity, and its performance is much better than both di erential braking and active steering. This research proposes an integrated control system that can simultaneously invoke di erential braking and active steering of multi-axle vehicles to fully utilize the abilities and potentials of the two control methods. 展开更多
关键词 Di erential braking Active steering Vertical tire force calculation Multi-axle truck integrated control
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Adaptive Dynamic Surface Control for Integrated Missile Guidance and Autopilot 被引量:17
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作者 Ming-Zhe Hou Guang-Ren Duan 《International Journal of Automation and computing》 EI 2011年第1期122-127,共6页
Integrated guidance and control for homing missiles utilizing adaptive dynamic surface control approach is considered based on the three channels independence design idea. A time-varying integrated guidance and contro... Integrated guidance and control for homing missiles utilizing adaptive dynamic surface control approach is considered based on the three channels independence design idea. A time-varying integrated guidance and control model with unmatched uncertainties is first formulated for the pitch channel, and an adaptive dynamic surface control algorithm is further developed to deal with these unmatched uncertainties. It is proved that the proposed feedback controller can ensure not only the accuracy of target interception, but also the stability of the missile dynamics. Then, the same control approach is further applied to the control design of the yaw and roll channels. The 6-degree-of-freedom (6-DOF) nonlinear missile simulation results demonstrate the feasibility and advantage of the proposed integrated guidance and control design scheme. 展开更多
关键词 integrated guidance and control unmatched uncertainty adaptive control dynamic surface control homing missiles.
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Integrated guidance and control design for missile with terminal impact angle constraint based on sliding mode control 被引量:21
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作者 Peng Wu Ming Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第4期623-628,共6页
Aimed at the guidance requirements of some missiles which attack targets with terminal impact angle at the terminal point,a new integrated guidance and control design scheme based on variable structure control approac... Aimed at the guidance requirements of some missiles which attack targets with terminal impact angle at the terminal point,a new integrated guidance and control design scheme based on variable structure control approach for missile with terminal impact angle constraint is proposed.First,a mathematical model of an integrated guidance and control model in pitch plane is established,and then nonlinear transformation is employed to transform the mathematical model into a standard form suitable for sliding mode control method design.A sufficient condition for the existence of linear sliding surface is given in terms of linear matrix inequalities(LMIs),based on which the corresponding reaching motion controller is also developed.To verify the effectiveness of the proposed integrated design scheme,the numerical simulation of missile is made.The simulation results demonstrate that the proposed guidance and control law can guide missile to hit the target with desired impact angle and desired flight attitude angle simultaneously. 展开更多
关键词 GUIDANCE terminal impact angle sliding mode control integrated guidance and control linear matrix inequality(LMI).
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Design and Analysis of Integrated Predictive Iterative Learning Control for Batch Process Based on Two-dimensional System Theory 被引量:3
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作者 陈宸 熊智华 钟宜生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第7期762-768,共7页
Based on the two-dimensional (2D) system theory, an integrated predictive iterative learning control (2D-IPILC) strategy for batch processes is presented. First, the output response and the error transition model ... Based on the two-dimensional (2D) system theory, an integrated predictive iterative learning control (2D-IPILC) strategy for batch processes is presented. First, the output response and the error transition model predictions along the batch index can be calculated analytically due to the 2D Roesser model of the batch process. Then, an integrated framework of combining iterative learning control (ILC) and model predictive control (MPC) is formed reasonably. The output of feedforward ILC is estimated on the basis of the predefined process 2D model. By min- imizing a quadratic objective function, the feedback MPC is introduced to obtain better control performance for tracking problem of batch processes. Simulations on a typical batch reactor demonstrate that the satisfactory tracking performance as well as faster convergence speed can be achieved than traditional proportion type (P- t-we) ILC despite the model error and disturbances. 展开更多
关键词 lterative learning control Model predictive control integrated control Batch process Two-dimensional systems
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INTEGRATED CONTROL FOR VEHICLE YAW MOTION USING DOUBLE-COST-FUNCTION LQR 被引量:5
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《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第3期228-233,共7页
关键词 In integrated control FOR VEHICLE YAW MOTION USING DOUBLE-COST-FUNCTION LQR
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Parameters Sensitivity Characteristics of Highly Integrated Valve-Controlled Cylinder Force Control System 被引量:8
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作者 Kai-Xian Ba Bin Yu +4 位作者 Xiang-Dong Kong Chun-He Li Qi-Xin Zhu Hua-Long Zhao Ling-Jian Kong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第2期159-175,共17页
Nowadays, a highly integrated valve?controlled cylinder(HIVC) is applied to drive the joints of legged robots. Although the adoption of HIVC has resulted in high?performance robot control, the hydraulic force system s... Nowadays, a highly integrated valve?controlled cylinder(HIVC) is applied to drive the joints of legged robots. Although the adoption of HIVC has resulted in high?performance robot control, the hydraulic force system still has problems, such as strong nonlinearity, and time?varying parameters. This makes HIVC force control very diffcult and complex. How to improve the control performance of the HIVC force control system and find the influence rule of the system parameters on the control performance is very significant. Firstly, the mathematical model of HIVC force control system is established. Then the mathematical expression for parameter sensitivity matrix is obtained by applying matrix sensitivity analysis(PSM). Then, aimed at the sinusoidal response under(three factors and three levels) working conditions, the simulation and the experiment are conducted. While the error between the simulation and experiment can’t be avoided. Therefore, combined with the range analysis, the error in the two performance indexes of sinusoidal response under the whole working condition is analyzed. Besides, the sensitivity variation pattern for each system parameter under the whole working condition is figured out. Then the two sensitivity indexes for the three system parameters, which are supply pressure, proportional gain and initial displacement of piston, are proved experimentally. The proposed method significantly reveals the sensitivity characteristics of HIVC force control system, which can make the contribution to improve the control performance. 展开更多
关键词 Highly integrated valve?controlled cylinder system Force control system Matrix sensitivity analysis Orthogonal test design Sensitivity index
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Progress on Integrated Control of Tobacco Black Shank 被引量:3
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作者 Yonghui XIE Yonggui ZHANG +2 位作者 Liquan ZHU Daogui YOU Yao LU 《Agricultural Biotechnology》 CAS 2015年第4期37-41,共5页
Tobacco black shank is one of the devastating diseases of tobacco. In recent years, this disease widely occurred in most tobacco-growing areas, which caused disastrous losses and has severely threatened the sustainabl... Tobacco black shank is one of the devastating diseases of tobacco. In recent years, this disease widely occurred in most tobacco-growing areas, which caused disastrous losses and has severely threatened the sustainable development of flue-cured tobacco. In order to lay a theoretical foundation for the better control of tobacco black shank, the occurrence characteristics and integrated control strategis of this disease were systematically discussed according to the aspects of agricultural control, chemical control, biological control, etc. 展开更多
关键词 TOBACCO Black shank integrated control Research progress
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THROTTLE CONTROL STRATEGIES IN THE PROCESS OF INTEGRATED POWERTRAIN CONTROL 被引量:6
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作者 Lei Yulong Gao Bingzhao +2 位作者 Tian Hua Ge Anlin Yan Su 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期429-433,共5页
Combining with the development of automated manual transmission (AMT), the various throttle control demands are analyzed under different working conditions of AMT such as tracking acceleration pedal, start, shift an... Combining with the development of automated manual transmission (AMT), the various throttle control demands are analyzed under different working conditions of AMT such as tracking acceleration pedal, start, shift and so on. Based on simulation, the responding throttle control strategies are proposed, and a simple but effective throttle control method is presented. The testing results have proved that the strategies are effective for improving the pedal tracking precision and the qualities of start and shift. 展开更多
关键词 Electronic throttle control Automated manual transmission integrated powertrain control
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Integrated Approach to Control False Smut in Hybrid Rice in Sichuan Province, China 被引量:2
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作者 LIANG Yan ZHANG Xue-mei +3 位作者 LI De-qiang HUANG Fu HU Pei-song PENG Yun-liang 《Rice science》 SCIE 2014年第6期354-360,共7页
Severe epidemic of false smut, caused by Ustilaginoidea virens (Cooke) Takahashi (teleomorph Villosiclava virens) has been reported in different parts of Asia and America. Different fungicides or bio-control agent... Severe epidemic of false smut, caused by Ustilaginoidea virens (Cooke) Takahashi (teleomorph Villosiclava virens) has been reported in different parts of Asia and America. Different fungicides or bio-control agents against false smut were applied at different times before heading on a susceptible rice variety Pu-6. A control efficiency as high as 91.92% was resulted from spraying 2.5% Wenquning, a suspension of Bacillus subtilis in solution of validamycin with 4.5 L/hm2 at 6 d before heading. Among the 186 hybrid rice screened in 2010, low significant correlations between the dates of full heading, rates of infected plants and panicles as well as the number of infected florets were found, with the correlation coefficients ranging from 0.2331 to 0.5212. However, significant difference in susceptibility coefficients was also found between the varieties which had the same dates of full heading. In the plot experiments to compare the susceptibility in 2011, the average rates of infected panicles of Yixiangyou 2168, Chuanxiangyou 3, Dexiang 4103, Yixiangyou 2115, Nei5you 317, Yangxinyou 1 were significantly lower than those of the control varieties Gangyou 725 and Gangyou 188 at the disease nursery located at Qionglai, Sichuan Province, China. When Neixiangyou 8156 and Nei5you 317 were sprayed with 2.5% Wenquning at 4.5 L/hm2 for two times at 6 d before and 1 d after heading, respectively, the control efficiencies of Nei5you 317 and Neixiangyou 8156 were respectively 100% and 82.24% compared to that of Gangyou 725. Satisfactory control effects had also obtained by single spray of 2.5% Wenquning at 4.5 L/hm2 at 5-6 d before heading. Therefore, less susceptible hybrid rice in combination with spraying Wenquning at 5-6 d before heading was suggested for the disease control in Sichuan Province, China. 展开更多
关键词 hybrid rice Ustilaginoidea virens validamycin Bacillus subtilis Bs-916 integrated control
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Integrated guidance and control of guided projectile with multiple constraints based on fuzzy adaptive and dynamic surface 被引量:6
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作者 Shang Jiang Fu-qing Tian +1 位作者 Shi-yan Sun Wei-ge Liang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第6期1130-1141,共12页
Based on fuzzy adaptive and dynamic surface(FADS),an integrated guidance and control(IGC)approach was proposed for large caliber naval gun guided projectile,which was robust to target maneuver,canard dynamic character... Based on fuzzy adaptive and dynamic surface(FADS),an integrated guidance and control(IGC)approach was proposed for large caliber naval gun guided projectile,which was robust to target maneuver,canard dynamic characteristics,and multiple constraints,such as impact angle,limited measurement of line of sight(LOS)angle rate and nonlinear saturation of canard deflection.Initially,a strict feedback cascade model of IGC in longitudinal plane was established,and extended state observer(ESO)was designed to estimate LOS angle rate and uncertain disturbances with unknown boundary inside and outside of system,including aerodynamic parameters perturbation,target maneuver and model errors.Secondly,aiming at zeroing LOS angle tracking error and LOS angle rate in finite time,a nonsingular terminal sliding mode(NTSM)was designed with adaptive exponential reaching law.Furthermore,combining with dynamic surface,which prevented the complex differential of virtual control laws,the fuzzy adaptive systems were designed to approximate observation errors of uncertain disturbances and to reduce chatter of control law.Finally,the adaptive Nussbaum gain function was introduced to compensate nonlinear saturation of canard deflection.The LOS angle tracking error and LOS angle rate were convergent in finite time and whole system states were uniform ultimately bounded,rigorously proven by Lyapunov stability theory.Hardware-in-the-loop simulation(HILS)and digital simulation experiments both showed FADS provided guided projectile with good guidance performance while striking targets with different maneuvering forms. 展开更多
关键词 integrated guidance and control Multiple constraints Fuzzy adaptive Dynamic surface Nonsingular terminal sliding mode Extended state observer
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Design and control of methyl acetate-methanol separation via heat-integrated pressure-swing distillation 被引量:13
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作者 Zhishan Zhang Qingjun Zhang +2 位作者 Guijie Li Meiling Liu Jun Gao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第11期1584-1599,共16页
Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum ... Design and control of pressure-swing distillation(PSD) with different heat integration modes for the separation of methyl acetate/methanol azeotrope are explored using Aspen Plus and Aspen Dynamics. First, an optimum steady-state separation configuration conditions are obtained via taking the total annual cost(TAC) or total reboiler heat duty as the objective functions. The results show that about 27.68% and 25.40% saving in TAC can be achieved by the PSD with full and partial heat integration compared to PSD without heat integration. Second,temperature control tray locations are obtained according to the sensitivity criterion and singular value decomposition(SVD) analysis and the single-end control structure is effective based on the feed composition sensitivity analysis. Finally, the comparison of dynamic controllability is made among various control structures for PSD with partial and full heat integration. It is shown that both control structures of composition/temperature cascade and pressure-compensated temperature have a good dynamic response performance for PSD with heat integration facing feed flowrate and composition disturbances. However, PSD with full heat integration performs the poor controllability despite of a little bit of economy. 展开更多
关键词 Pressure-swing distillation Azeotrope Heat integration Dynamic control Methyl acetate/methanol
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