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Function of Cooperative Learning in Developing Positive Affect
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作者 佟玉平 《中国校外教育》 2008年第7期31-,共1页
This paper focus on the function of cooperative learning in developing positive affect,Including reducing anxiety,increasing motivation,facilitating the development of positive attitudes toward learning and language l... This paper focus on the function of cooperative learning in developing positive affect,Including reducing anxiety,increasing motivation,facilitating the development of positive attitudes toward learning and language learning,promoting self-esteem,as well as supporting different learning styles and encouraging perseverance in the difficult and confusing process of learning a foreign language. 展开更多
关键词 function cooperative learning positive Affect
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Binding Equilibrium Studies Between Co^(2+) and HSA or BSA 被引量:3
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作者 BIAN He dong LIANG Hong +2 位作者 TU Chu qiao ZHANG Hong zhi SHEN Pan wen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第3期276-279,共4页
关键词 Co 2+ serum albumin Equilibrium dialysis Coordination analysis positive cooperative effect
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Improved GNSS Cooperation Positioning Algorithm for Indoor Localization 被引量:4
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作者 Taoyun Zhou Baowang Lian +2 位作者 Siqing Yang Yi Zhang Yangyang Liu 《Computers, Materials & Continua》 SCIE EI 2018年第8期225-245,共21页
For situations such as indoor and underground parking lots in which satellite signals are obstructed,GNSS cooperative positioning can be used to achieve highprecision positioning with the assistance of cooperative nod... For situations such as indoor and underground parking lots in which satellite signals are obstructed,GNSS cooperative positioning can be used to achieve highprecision positioning with the assistance of cooperative nodes.Here we study the cooperative positioning of two static nodes,node 1 is placed on the roof of the building and the satellite observation is ideal,node 2 is placed on the indoor windowsill where the occlusion situation is more serious,we mainly study how to locate node 2 with the assistance of node 1.Firstly,the two cooperative nodes are located with pseudo-range single point positioning,and the positioning performance of cooperative node is analyzed,therefore the information of pseudo-range and position of node 1 is obtained.Secondly,the distance between cooperative nodes is obtained by using the baseline method with double-difference carrier phase.Finally,the cooperative location algorithms are studied.The Extended Kalman Filtering(EKF),Unscented Kalman Filtering(UKF)and Particle Filtering(PF)are used to fuse the pseudo-range,ranging information and location information respectively.Due to the mutual influences among the cooperative nodes in cooperative positioning,the EKF,UKF and PF algorithms are improved by resetting the error covariance matrix of the cooperative nodes at each update time.Experimental results show that after being improved,the influence between the cooperative nodes becomes smaller,and the positioning performance of the nodes is better than before. 展开更多
关键词 Indoor localization GNSS cooperative positioning extended kalman filtering(EKF) unscented kalman filtering(UKF) particle filtering(PF)
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State estimation of connected vehicles using a nonlinear ensemble filter
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作者 刘江 陈华展 +1 位作者 蔡伯根 王剑 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2406-2415,共10页
The concept of connected vehicles is with great potentials for enhancing the road transportation systems in the future. To support the functions and applications under the connected vehicles frame, the estimation of d... The concept of connected vehicles is with great potentials for enhancing the road transportation systems in the future. To support the functions and applications under the connected vehicles frame, the estimation of dynamic states of the vehicles under the cooperative environments is a fundamental issue. By integrating multiple sensors, localization modules in OBUs(on-board units) require effective estimation solutions to cope with various operation conditions. Based on the filtering estimation framework for sensor fusion, an ensemble Kalman filter(En KF) is introduced to estimate the vehicle's state with observations from navigation satellites and neighborhood vehicles, and the original En KF solution is improved by using the cubature transformation to fulfill the requirements of the nonlinearity approximation capability, where the conventional ensemble analysis operation in En KF is modified to enhance the estimation performance without increasing the computational burden significantly. Simulation results from a nonlinear case and the cooperative vehicle localization scenario illustrate the capability of the proposed filter, which is crucial to realize the active safety of connected vehicles in future intelligent transportation. 展开更多
关键词 connected vehicles state estimation cooperative positioning nonlinear ensemble filter global navigation satellite system (GNSS) dedicated short range communication (DSRC)
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A Stochastic Approach for Cooperative Position Estimation of Multiple Mobile Robots
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《Journal of Mechanics Engineering and Automation》 2014年第1期25-34,共10页
This paper proposes the cooperative position estimation of a group of mobile robots, which pertbrms disaster relief tasks in a wide area. When searching the wide area, it becomes important to know a robot's position ... This paper proposes the cooperative position estimation of a group of mobile robots, which pertbrms disaster relief tasks in a wide area. When searching the wide area, it becomes important to know a robot's position correctly. However, for each mobile robot, it is impossible to know its own position correctly. Therefore, each mobile robot estimates its position from the data of sensor equipped on it. Generally, the sensor data is incorrect since there is sensor noise, etc. This research considers two types of the sensor data errors from omnidirectional camera. One is the error of white noise of the image captured by omnidirectional camera and so on. Another is the error of position and posture between two omnidirectional cameras. To solve the error of latter case, we proposed a self-position estimation algorithm for multiple mobile robots using two omnidirectional cameras and an accelerometer. On the other hand, to solve the error of the former case, this paper proposed an algorithm of cooperative position estimation for multiple mobile robots. In this algorithm, each mobile robot uses two omnidirectional cameras to observe the surrounding mobile robot and get the relative position between mobile robots. Each mobile robot estimates its position with only measurement data of each other mobile robots. The algorithm is based on a Bayesian filtering. Simulations of the proposed cooperative position estimation algorithm for multiple mobile robots are performed. The results show that position estimation is possible by only using measurement value from each other robot. 展开更多
关键词 Multiple mobile robots omnidirectional cameras cooperative stochastic position estimation algorithm.
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Simultaneous Position Estimation and Omnidirectional Camera Parameter Calibration for Multiple Mobile Robots
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作者 Kosuke Sasahara Akinori Nagano Zhi-Wei Luo 《Journal of Mechanics Engineering and Automation》 2014年第2期106-115,共10页
This paper proposed an algorithm on simultaneous position estimation and calibration of omnidirectional camera parameters for a group of multiple mobile robots. It is aimed at developing of exploration and information... This paper proposed an algorithm on simultaneous position estimation and calibration of omnidirectional camera parameters for a group of multiple mobile robots. It is aimed at developing of exploration and information gathering robotic system in unknown environment. Here, each mobile robot is not possible to know its own position. It can only estimate its own position by using the measurement value including white noise acquired by two omnidirectional cameras mounted on it. Each mobile robot is able to obtain the distance to those robots observed from the images of two omnidirectional cameras while making calibration during moving but not in advance. Simulation of three robots moving straightly shows the effectiveness of the proposed algorithm. 展开更多
关键词 Multiple mobile robots omnidirectional camera cooperative stochastic position estimation algorithm.
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A whole-net cooperative positioning method based on CDGNSS and inter-vehicle ranging
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作者 Shan HU Hongbo ZHAO Chen ZHUANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第2期401-416,共16页
Relative positioning is recognized as an important issue for vehicles in urban environments.Multi-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ... Relative positioning is recognized as an important issue for vehicles in urban environments.Multi-vehicle Cooperative Positioning(CP)techniques which fuse the Global Navigation Satellite System(GNSS)and inter-vehicle ranging have attracted attention in improving the performance of baseline estimation between vehicles.However,current CP methods estimate the baselines separately and ignore the interactions among the positioning information of different baselines.These interactions are called’information coupling’.In this work,we propose a new multivehicle precise CP framework using the coupled information in the network based on the Carrier Differential GNSS(CDGNSS)and inter-vehicle ranging.We demonstrate the benefit of the coupled information by deriving the Cramer-Rao Lower Bound(CRLB)of the float estimation in CP.To fully use this coupled information,we propose a Whole-Net CP(WN-CP)method which consists of the Whole-Net Extended Kalman Filter(WN-EKF)as the float estimation filter,and the Partial Baseline Fixing(PBF)as the ambiguity resolution part.The WN-EKF fuses the measurements of all baselines simultaneously to improve the performance of float estimation,and the PBF strategy fixes the ambiguities of the one baseline to be estimated,instead of full ambiguity resolution,to reduce the computation load of ambiguity resolution.Field tests involving four vehicles were conducted in urban environments.The results show that the proposed WN-CP method can achieve better performance and meanwhile maintain a low computation load compared to the existing methods. 展开更多
关键词 GNSS Cooperative positioning BASELINE Ambiguity resolution Information coupling
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Use of land's cooperative object to estimate UAV's pose for autonomous landing 被引量:9
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作者 Xu Guili Qi Xiaopeng +3 位作者 Zeng Qinghua Tian Yupeng Guo Ruipeng Wang Biao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第6期1498-1505,共8页
The research of unmanned aerial vehicles'(UAVs')autonomy navigation and landing guidance with computer vision has important signifcance.However,because of the image blurring,the position of the cooperative points ... The research of unmanned aerial vehicles'(UAVs')autonomy navigation and landing guidance with computer vision has important signifcance.However,because of the image blurring,the position of the cooperative points cannot be obtained accurately,and the pose estimation algorithms based on the feature points have low precision.In this research,the pose estimation algorithm of UAV is proposed based on feature lines of the cooperative object for autonomous landing.This method uses the actual shape of the cooperative-target on ground and the principle of vanishing line.Roll angle is calculated from the vanishing line.Yaw angle is calculated from the location of the target in the image.Finally,the remaining extrinsic parameters are calculated by the coordinates transformation.Experimental results show that the pose estimation algorithm based on line feature has a higher precision and is more reliable than the pose estimation algorithm based on points feature.Moreover,the error of the algorithm we proposed is small enough when the UAV is near to the landing strip,and it can meet the basic requirements of UAV's autonomous landing. 展开更多
关键词 Computer vision Cooperative object Landing Position measurement UAV Vanishing line
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Binding equilibrium study between Mn( Ⅱ ) and HSA or BSA 被引量:2
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作者 梁宏 涂楚桥 +3 位作者 张宏志 沈星灿 周永洽 申泮文 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2000年第1期35-41,共7页
The binding of Mn( Ⅱ ) to human serum albumin (HSA) or bovine serum albumin (BSA) has been studied by equilibrium dialysis at physiological pH (7. 43). The Scatchard analysis indicates that there are 1.8 and 1.9 stro... The binding of Mn( Ⅱ ) to human serum albumin (HSA) or bovine serum albumin (BSA) has been studied by equilibrium dialysis at physiological pH (7. 43). The Scatchard analysis indicates that there are 1.8 and 1.9 strong binding sites of Mn( Ⅱ ) in HSA and BSA, respectively. The successive stability constants which are reported for the first time are obtained by non-linear least-squares methods fitting Bjerrum formula. For both Mn( Ⅱ )-HSA and Mn( Ⅱ )-BSA systems, the order of magnitude of K1 was found to be 104. The analyses of Hill plots and free energy coupling show that the positive cooperative effect was found in both Mn( Ⅱ )-HSA and Mn( Ⅱ )-BSA systems . The results of Mn ( Ⅱ ) competing with Cu ( Ⅱ ) 、 Zn(Ⅱ)、Cd( Ⅱ) or Ca( Ⅱ ) to bind to HSA or BSA further support the conjecture that there are two strong binding sites of Mn( Ⅱ) in both HSA and BSA. One is most probably located at the tripeptide segment of N- terminal sequence of HSA and BSA molecules involving four groups composed of n 展开更多
关键词 Mn (Ⅱ)-serum albumin equilibrium dialysis successive stability constants positive cooperative effect coordination analysis
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