期刊文献+
共找到176篇文章
< 1 2 9 >
每页显示 20 50 100
Global prescribed performance control for lane-keeping of automated vehicles considering input saturation
1
作者 Zhibang Si Yujuan Wang +1 位作者 Qing Chen Manling Wu 《Journal of Automation and Intelligence》 2025年第1期65-71,共7页
This paper addresses the lane-keeping control problem for autonomous ground vehicles subject to input saturation and uncertain system parameters.An enhanced adaptive terminal sliding mode based prescribed performance ... This paper addresses the lane-keeping control problem for autonomous ground vehicles subject to input saturation and uncertain system parameters.An enhanced adaptive terminal sliding mode based prescribed performance control scheme is proposed,which enables the lateral position error of the vehicle to be kept within the prescribed performance boundaries all the time.This is achieved by firstly introducing an improved performance function into the controller design such that the stringent initial condition requirements can be relaxed,which further allows the global prescribed performance control result,and then,developing a multivariable adaptive terminal sliding mode based controller such that both input saturation and parameter uncertainties are handled effectively,which further ensures the robust lane-keeping control.Finally,the proposed control strategy is validated through numerical simulations,demonstrating its effectiveness. 展开更多
关键词 Lane keeping Global prescribed performance Adaptive terminal sliding mode control Input saturation
在线阅读 下载PDF
一个基于Keeping Up with the Joneses的随机内生增长模型
2
作者 王海军 《应用数学》 CSCD 北大核心 2008年第3期471-475,共5页
本文建立了一个基于Keeping up with the Joneses的随机内生增长模型,利用"伪双状态变量"法得到了均衡时的最优消费、最优经济增长率和最优福利,讨论了相对消费对它们的影响.
关键词 keeping up with the Joneses 内生增长 “伪双状态变量”法 相对消费
在线阅读 下载PDF
Suggestions of keeping L2 motivation
3
作者 徐斌 《海外英语》 2014年第6X期86-87,共2页
How will we keep the motivation during the second language as long as we can,which confuses us,though what the L2 motivation is and how it is developed have been discussed by the psychologists,educators,etc.The aim of... How will we keep the motivation during the second language as long as we can,which confuses us,though what the L2 motivation is and how it is developed have been discussed by the psychologists,educators,etc.The aim of this passage is to clarify the basic content of motivation,including the definition,classification,importance,etc.how the current situation is in senior high students’English learning motivation,what should be done to keep such motivation.In the following part,it will be read that the introduction,the chapter stating the content and classification of(L2)motivation,the chapter analyzing the necessity and state of L2 motivation at senor high,the chapter offering approach to keep that motivation,and the conclusion.All of them use the comparison,explanation and cites. 展开更多
关键词 SENIOR HIGH STUDENTS keeping (L2) MOTIVATION L2 AC
在线阅读 下载PDF
Three-dimensional formation keeping of multi-UAV based on consensus 被引量:4
4
作者 ZHU Xu ZHANG Xun-xun +1 位作者 YAN Mao-de QU Yao-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第6期1387-1395,共9页
Consensus is an emerging technique using neighbor-to-neighbor interaction to generate steering commands for cooperative control of multiple vehicles. A three-dimensional formation keeping strategy for multiple unmanne... Consensus is an emerging technique using neighbor-to-neighbor interaction to generate steering commands for cooperative control of multiple vehicles. A three-dimensional formation keeping strategy for multiple unmanned aerial vehicles(multi-UAV) is proposed based on consensus, aiming at maintaining a specified geometric configuration. A formation control algorithm with guidance and corresponding flight controllers is given, managing position and attitude, respectively. In order to follow a three-dimensional predefined flight path, by introducing the tracking orders as reference states into the consensus, the formation control algorithm is designed, following the predefined flight path and maintaining geometric configuration simultaneously. The flight controllers are constructed by nonlinear dynamic inverse, including attitude design and velocity design. With the whole system composed of a nonlinear six-degree-of-freedom UAV model, the formation control algorithm and the flight controllers, the formation keeping strategy is closed loop and with full states. In simulation, three-dimensional formation flight demonstrates the feasibility and effectiveness of the proposed strategy. 展开更多
关键词 multiple unmanned AERIAL VEHICLES formation keeping CONSENSUS REFERENCE state FLIGHT control
在线阅读 下载PDF
Genetic Model for Fresh-keeping Character in Sweet Corn
5
作者 黄成威 陈沛君 +3 位作者 秦彤非 张大伟 张永顺 蒋锋 《Agricultural Science & Technology》 CAS 2016年第8期1823-1827,共5页
This study was conducted to investigate the genetic regularity of indexes related to freshness keeping and its molecular basis by acquiring 6 generations (P1, P2, F1, B1, B2 and F2) of an inbred line T3 with long fr... This study was conducted to investigate the genetic regularity of indexes related to freshness keeping and its molecular basis by acquiring 6 generations (P1, P2, F1, B1, B2 and F2) of an inbred line T3 with long freshness period × an inbred line T15 with short freshness period in sweet corn. The genetic analysis of the indexes was performed by major gene+polygene mixed genetic model combined with the genetic analysis combining six generations.The results showed that the decreasing rate of the postharvest sugar content in the T3 was controlled by two pairs of additive-dominante-epistatic major genes+additive-dominant polygenes; each segregating generation was affected by its major genes, the heritability of major genes and polygene in the B1 generation was 74.63% and 17.67%, respectively; the heritability of major gene and potygene in the B2 was 91.98% and 0,00%, respectively; and the heritability of major gene and polygene inthe F2 was 82.67%, and 12.93%, respectively. 展开更多
关键词 Sweet corn Fresh keeping Genetic model
在线阅读 下载PDF
Direct adaptive control for lane keeping in intelligent vehicle systems 被引量:4
6
作者 张京明 任殿波 +1 位作者 崔胜民 张继业 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第6期810-814,共5页
In this paper, with parametric uncertainties such as the mass of vehicle, the inertia of vehicle about vertical axis, and the tire cornering stiffness, we deal with the vehicle lateral control problem in intelligent v... In this paper, with parametric uncertainties such as the mass of vehicle, the inertia of vehicle about vertical axis, and the tire cornering stiffness, we deal with the vehicle lateral control problem in intelligent vehicle systems. Based on the dynamical model of vehicle, by applying Lyapunov function method, the control problem for lane keeping in the presence of parametric uncertainty is studied, the direct adaptive algorithm to compensate for parametric variations is proposed and the terminal sliding mode variable structure control laws are designed with look-ahead references systems. The stability of the system is investigated from the zero dynamics analysis. Simulation results show that convergence rates of the lateral displacement error, yaw angle error and slid angle are fast. 展开更多
关键词 intelligent vehicle systems lane keeping direct adaptive control Lyapunov function method
在线阅读 下载PDF
Concept Design,Modeling and Station-keeping Attitude Control of an Earth Observation Platform 被引量:2
7
作者 YANG Yuenen WU Jie ZHENG Wei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1245-1254,共10页
The stratosphere airship provides a unique and promising platform for earth observation. Researches on the project design and control scheme for earth observation platforms are still rarely documented. Nonlinear dynam... The stratosphere airship provides a unique and promising platform for earth observation. Researches on the project design and control scheme for earth observation platforms are still rarely documented. Nonlinear dynamics, model uncertainties, and external disturbances contribute to the difficulty in maneuvering the stratosphere airship. A key technical challenge for the earth observation platform is station keeping, or the ability to remain fixed over a geo-location. This paper investigates the conceptual design, modeling and station-keeping attitude control of the near-space earth observation platform. A conceptual design of the earth observation platform is presented. The dynamics model of the platform is derived from the Newton-Euler formulation, and the station-keeping control system of the platform is formulated. The station-keeping attitude control approach for the platform is proposed. The multi-input multi-output nonlinear control system is decoupled into three single-input single-output linear subsystems via feedback linearization, the attitude controller design is carried out on the new linear systems using terminal sliding mode control, and the global stability of the closed-loop system is proven by using the Lyapunov theorem. The performance of the designed control system is simulated by using the variable step Runge-Kutta integrator. Simulation results show that the control system tracks the commanded attitude with an error of zero, which verify the effectiveness and robustness of the designed control system in the presence of parametric uncertainties. The near-space earth observation platform has several advantages over satellites, such as high resolution, fast to deploy, and convenient to retrieve, and the proposed control scheme provides an effective approach for station-keeping attitude control of the earth observation platform. 展开更多
关键词 earth observation platform novel design attitude control terminal sliding mode station keeping near-space
在线阅读 下载PDF
Stochastic Model Predictive Control Approach to Autonomous Vehicle Lane Keeping 被引量:3
8
作者 ZHANG Chenzhi ZHUANG Cheng +2 位作者 ZHENG Xueke CAI Runze LI Mian 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第5期626-633,共8页
In real-world scenarios,the uncertainty of measurements cannot be handled efficiently by traditional model predictive control(MPC).A stochastic MPC(SMPC)method for handling the uncertainty of states in autonomous driv... In real-world scenarios,the uncertainty of measurements cannot be handled efficiently by traditional model predictive control(MPC).A stochastic MPC(SMPC)method for handling the uncertainty of states in autonomous driving lane-keeping scenarios is presented in this paper.A probabilistic system is constructed by considering the variance of states.The probabilistic problem is then transformed into a solvable deterministic optimization problem in two steps.First,the cost function is separated into mean and variance components.The mean component is calculated online,whereas the variance component can be calculated offline.Second,Cantelli’s inequality is adopted for the deterministic reformulation of constraints.Consequently,the original probabilistic problem is transformed into a quadratic programming problem.To validate the feasibility and effectiveness of the proposed control method,we compared the SMPC controller with a traditional MPC controller in a lane-keeping scenario.The results demonstrate that the SMPC controller is more effective overall and produces smaller steady-state distance errors. 展开更多
关键词 stochastic model predictive control(SMPC) autonomous driving lane keeping
原文传递
Stability-Considered Lane Keeping Control of Commercial Vehicles Based on Improved APF Algorithm 被引量:1
9
作者 Bin Tang Zhengyi Yang +3 位作者 Haobin Jiang Ziyan Lin Zhanxiang Xu Zitian Hu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期114-129,共16页
Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase... Regarding the lane keeping system,path tracking accuracy and lateral stability at high speeds need to be taken into account especially for commercial vehicles due to the characteristics of larger mass,longer wheelbase and higher mass center.To improve the performance mentioned above comprehensively,the control strategy based on improved artificial potential field(APF)algorithm is proposed.In the paper,time to lane crossing(TLC)is introduced into the potential field function to enhance the accuracy of path tracking,meanwhile the vehicle dynamics parameters including yaw rate and lateral acceleration are chosen as the repulsive force field source.The lane keeping controller based on improved APF algorithm is designed and the stability of the control system is proved based on Lyapunov theory.In addition,adaptive inertial weight particle swarm optimization algorithm(AIWPSO)is applied to optimize the gain of each potential field function.The co-simulation results indicate that the comprehensive evaluation index respecting lane tracking accuracy and lateral stability is reduced remarkably.Finally,the proposed control strategy is verified by the HiL test.It provides a beneficial reference for dynamics control of commercial vehicles and enriches the theoretical development and practical application of artificial potential field method in the field of intelligent driving. 展开更多
关键词 Lane keeping control Commercial vehicles Lateral stability Artificial potential field AIWPSO
在线阅读 下载PDF
Design of House Keeping System for a Certain Micro Satellite 被引量:2
10
作者 马秀娟 Cao +4 位作者 Xibin Xu Guodong Ma Xingrui 《High Technology Letters》 EI CAS 2001年第4期69-72,共4页
This paper presents the design of hardware and software of the house keeping system for a certain micro satellite. The system uses micro electronic technique, large scale integrated circuits, processors and computers ... This paper presents the design of hardware and software of the house keeping system for a certain micro satellite. The system uses micro electronic technique, large scale integrated circuits, processors and computers which has the advantages of strong function, high flexibility and reliability, It satisfies the requirements for efficient performance,light weight, small volume,and low consumption of power for micro satellite. 展开更多
关键词 House keeping system Hardware structure Software design
在线阅读 下载PDF
Formation Feedback Applied to Behavior-Based Approach to Formation Keeping 被引量:1
11
作者 苏治宝 陆际联 《Journal of Beijing Institute of Technology》 EI CAS 2004年第2期190-193,共4页
Approaches to the study of formation keeping for multiple mobile robots are analyzed and a behavior-based robot model is built in this paper. And, a kind of coordination architecture is presented, which is similar to ... Approaches to the study of formation keeping for multiple mobile robots are analyzed and a behavior-based robot model is built in this paper. And, a kind of coordination architecture is presented, which is similar to the infantry squad organization and is used to realize multiple mobile robots to keep formations. Simulations verify the validity of the approach to keep formation, which combines the behavior-based method and formation feedback. The effects of formation feedback on the performance of the system are analyzed. 展开更多
关键词 multiple mobile robots formation keeping behavior-based approach formation feedback
在线阅读 下载PDF
End-to-end learning for high-precision lane keeping via multi-state model 被引量:2
12
作者 Wei Yuan Ming Yang +2 位作者 Hao Li Chunxiang Wang Bing Wang 《CAAI Transactions on Intelligence Technology》 2018年第4期185-190,共6页
High-precision lane keeping is essential for the future autonomous driving.However,due to the imbalanced and inaccurate datasets collected by human drivers,current end-to-end driving models have poor lane keeping the ... High-precision lane keeping is essential for the future autonomous driving.However,due to the imbalanced and inaccurate datasets collected by human drivers,current end-to-end driving models have poor lane keeping the effect.To improve the precision of lane keeping,this study presents a novel multi-state model-based end-to-end lane keeping method.First,three driving states will be defined:going straight,turning right and turning left.Second,the finite-state machine(FSM)table as well as three kinds of training datasets will be generated based on the three driving states.Instead of collecting the dataset by human drivers,the accurate dataset will be collected by the high-performance path following controller.Third,three sets of parameters based on 3DCNN-LSTM model will be trained for going straight,turning left and turning right,which will be combined with FSM table to form a multi-state model.This study evaluates the multi-state model by testing it on five tracks and recording the lane keeping error.The result shows the multi-state model-based end-to-end method performs the higher precision of lane keeping than the traditional single end-to-end model. 展开更多
关键词 HIGH-PRECISION LANE keeping
在线阅读 下载PDF
3D Track-keeping Method for Autonomous Underwater Vehicle 被引量:1
13
作者 WANG Wei, Bian Xin-Qian, Chang Zong-HuCollege of Power and Nuclear Engineering, Harbin Engineering University, Harbin 150001, China 《哈尔滨工程大学学报(英文版)》 2002年第2期18-22,共5页
In this paper, 3D track-keeping control method for autonomous underwater vehicle (AUV) with and without the influence of ocean current is investigated. Because the system to be controlled is highly nonlinear and stron... In this paper, 3D track-keeping control method for autonomous underwater vehicle (AUV) with and without the influence of ocean current is investigated. Because the system to be controlled is highly nonlinear and strong coupled, an approach is used to divide it into two subsystems. One is to control the heading and the track error on the horizontal plane. The other is to control the pitch and the track error on the vertical plane. The results of computer simulation show that the autopilot works properly, it can capture the current waypoint and turns to track the next path automatically. 展开更多
关键词 AUV SLIDING MODE CONTROL 3D TRACK - keeping
在线阅读 下载PDF
AN INTRODUCTION TO KEEPING-FIT MASSAGE(1)
14
作者 臧福科 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1993年第2期120-123,共4页
Massage,called Anmo (pressing andrubbing) in ancient times,is a non-drugtherapy,characterized by its simplicity,con-venience,cheapness and effectiveness,whichhas been used as one of the effectivekeeping-fit measures s... Massage,called Anmo (pressing andrubbing) in ancient times,is a non-drugtherapy,characterized by its simplicity,con-venience,cheapness and effectiveness,whichhas been used as one of the effectivekeeping-fit measures since thausands ofyears ago.With gradual improvement of people’sliving standard,the problem of health carehas been put on the agenda,receiving a wideattention from the medical circle.SinceChina has a long history of civilization,scholars of successive ages have left to ournation ample valuable knowledge of healthcare.Among many theories I am much infavour of the keeping fit idea,the“ 展开更多
关键词 SIMPLICITY successive circle valuable keeping gradual PRESSING ANCIENT AGENDA instead
暂未订购
KEEPING-FIT MOXIBUSTION(6)
15
作者 袁立人 刘晓明 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 1993年第3期227-229,共3页
Among the traditional Chinese tech-niques of health preservation,keeping-fitmoxibustion is a unique and effective onefor achieving longevity.Generally,moxibustion consists of burning or fumingcertain drugs on certain ... Among the traditional Chinese tech-niques of health preservation,keeping-fitmoxibustion is a unique and effective onefor achieving longevity.Generally,moxibustion consists of burning or fumingcertain drugs on certain points to effect awarming or heating stimulation andconsequently,to treat diseases,strengthenthe body and achieve longavity as well. 展开更多
关键词 MOXIBUSTION STIMULATION PRESERVATION heating keeping minutes stored BURNING THREAD sized
暂未订购
Influence of hydroxypropyl methylcellulose edible coating on fresh-keeping and storability of tomato
16
作者 庄荣玉 黄耀文 《Journal of Zhejiang University Science》 CSCD 2003年第1期109-113,共5页
The effect of application of cellulose-based edible coating, hydroxypropyl methylcellulose (HPMC) to mature-green tomatoes on the firmness and color was investigated. Tomatoes were stored at 20℃ for up to 18 days. Fi... The effect of application of cellulose-based edible coating, hydroxypropyl methylcellulose (HPMC) to mature-green tomatoes on the firmness and color was investigated. Tomatoes were stored at 20℃ for up to 18 days. Firmness decreased as storage time increased in all treatments. However, application of HPMC edible coating delayed softening of tomatoes during 18 days of storage at 20℃ . At days 7, 13 and 18,the firmness of tomatoes coated with HPMC was significantly ( P ≤ 0.05) greater than the firmness of uncoated tomatoes. The study also confirmed that HPMC coatings could significantly (P≤0.05) delay the changes in color of tomatoes stored at 20℃ . The ripening of tomatoes from the pink stage to the red stage was successfully retarded. HPMC coating could extend the shelf life of fresh tomatoes. The retardation of the rate of loss of firmness could reduce the economic loss that would result from spoilage by mechanical injury during transportation of tomatoes. 展开更多
关键词 Hydroxypropyl methylcellulose Edible coating TOMATO Fresh\|keeping STORAGE
在线阅读 下载PDF
Sea Keeping Analysis of Air Cushion Vehicle with Different Wave Angles under the Operation Resistance
17
作者 周佳 唐文勇 张圣坤 《Journal of Shanghai Jiaotong university(Science)》 EI 2009年第4期471-475,共5页
The air cushion vehicle (ACV) sea keeping characteristic under different wave directions with the operation resistance is discussed with the couples of the heave, pitch roll motion and the pressure of the cushion. In ... The air cushion vehicle (ACV) sea keeping characteristic under different wave directions with the operation resistance is discussed with the couples of the heave, pitch roll motion and the pressure of the cushion. In previous researches, only wave and cross wave direction were discussed. Then a Matlab program is made to calculate the united frequency responses of heave, pitch and roll amplitude of the craft, under different wave frequencies and different wave directions. The results of the research depict some dangerous situations under which the sympathetic vibration happens in heave, pitch and roll motion and the amplitudes are extremely higher than those under the ordinary conditions. These results will be helpful in ACV design and operation. 展开更多
关键词 air cushion vehicle (ACV) sea keeping characteristic three phase coupling
原文传递
Fresh keeping techniques for purple cabbage
18
作者 黄绍力 黄健新 +1 位作者 徐勋志 常绍东 《Agricultural Science & Technology》 CAS 2004年第3期22-25,共4页
The cold storage period of purple cabbage packaged with the respirat ory cling film may last 150 days at 2℃by dipping the root with 200×iprodione. Normal temperature storage and quick-freezing storage(-18℃) are... The cold storage period of purple cabbage packaged with the respirat ory cling film may last 150 days at 2℃by dipping the root with 200×iprodione. Normal temperature storage and quick-freezing storage(-18℃) are not suitable for purple cabbage. 展开更多
关键词 purple cabbage IPRODIONE low temperature storage fresh keeping
在线阅读 下载PDF
The Integrated Study on Agritainment and the Industrial Economy of Keeping Good Health and Caring for the Senior
19
作者 Yijun MA 《Asian Agricultural Research》 2013年第5期35-36,共2页
Based on the development prospect of the industry of keeping in good health and caring for the senior and practical exploration on the Lishui Citys construction of "Health Blessed Land" in Yangtze River Delt... Based on the development prospect of the industry of keeping in good health and caring for the senior and practical exploration on the Lishui Citys construction of "Health Blessed Land" in Yangtze River Delta, the position, function and facing problems of agritainment in the system of industrial economy of keeping in good health and caring for the senior in Lishui City. From the view of the industry integration, this paper puts forward the new strategies of developing agritainment in terms of design concepts at the top level, guarantee conditions in the government, layout strategies stressing on resources, target assessment focusing on nourishing of life, the basic promoting connotation. 展开更多
关键词 AGRITAINMENT keeping in GOOD HEALTH and CARING for
在线阅读 下载PDF
Effects of Using Different Percentages of Fenugreek Flour to Improve the Sensory, Rheological Properties and Keeping Quality in Maize Dough to Produces Gluten-free Breads
20
作者 Abdulsalam Abdulrahman Rasool Dana Azad Abdulkhaleq Dlir Amin Sabir 《Journal of Agricultural Science and Technology(A)》 2013年第5期380-384,共5页
Adding different percentages 1%, 3% and 5% of fenugreek flour depending on maize flour base to gluten free bread recipe for making tanoor bread was used to improve the tanoor bread quality, in term of sensory properti... Adding different percentages 1%, 3% and 5% of fenugreek flour depending on maize flour base to gluten free bread recipe for making tanoor bread was used to improve the tanoor bread quality, in term of sensory properties like volume, crust, color, symmetry, bake uniformity, texture, grain, aroma and taste. Also some rheological properties like gelatinization temperature and maximum viscosity of dough with bread keeping quality were used. The aim of this work is to produce suitable bread with maintaining the bread quality by selecting the suitable percentage to produce gluten free bread for people who suffering from celiac diseases and its contribution to health benefits. Significant differences were observed by using 5% of fenugreek flour in term of gelatinization temperature, maximum viscosity, breed keeping quality and volume. While using 1% of fenugreek flour significantly improved symmetry value, bread texture, crumb color, aroma and taste. 展开更多
关键词 MAIZE FENUGREEK sensory evaluation rheological properties keeping quality gluten-free bread.
在线阅读 下载PDF
上一页 1 2 9 下一页 到第
使用帮助 返回顶部