Tracking precision of pre-planned trajectories is essential for an auto-guided vehicle (AGV). The purpose of this paper is to design a self-constructing wavelet neural network (SCWNN) method for dynamical modeling and...Tracking precision of pre-planned trajectories is essential for an auto-guided vehicle (AGV). The purpose of this paper is to design a self-constructing wavelet neural network (SCWNN) method for dynamical modeling and control of a 2-DOF AGV. In control systems of AGVs, kinematical models have been preferred in recent research documents. However, in this paper, to enhance the trajectory tracking performance through including the AGV’s inertial effects in the control system, a learned dynamical model is replaced to the kinematical kind. As the base of a control system, the mathematical models are not preferred due to modeling uncertainties and exogenous inputs. Therefore, adaptive dynamic and control models of AGV are proposed using a four-layer SCWNN system comprising of the input, wavelet, product, and output layers. By use of the SCWNN, a robust controller against uncertainties is developed, which yields the perfect convergence of AGV to reference trajectories. Owing to the adaptive structure, the number of nodes in the layers is adjusted in online and thus the computational burden of the neural network methods is decreased. Using software simulations, the tracking performance of the proposed control system is assessed.展开更多
This essay is going to read the different kinds of beings in The Lord of the Rings as different stages of man,and to analyze how they construct or destruct their selves respectively over power.The Lord of the Rings is...This essay is going to read the different kinds of beings in The Lord of the Rings as different stages of man,and to analyze how they construct or destruct their selves respectively over power.The Lord of the Rings is read as a story about the self-construction and self-destruction of man,who begins to construct the sense of self from a very early stage in life,and becomes who he is in the continuous process of trying to identify himself with the image that keeps changing,of the frequently alternative construction and destruction of his self,and of intersubjectivity,the interrelation with other subjects.展开更多
To improve the reliability and accuracy of the global po- sitioning system (GPS)/micro electromechanical system (MEMS)- inertial navigation system (INS) integrated navigation system, this paper proposes two diff...To improve the reliability and accuracy of the global po- sitioning system (GPS)/micro electromechanical system (MEMS)- inertial navigation system (INS) integrated navigation system, this paper proposes two different methods. Based on wavelet threshold denoising and functional coefficient autoregressive (FAR) model- ing, a combined data processing method is presented for MEMS inertial sensor, and GPS attitude information is also introduced to improve the estimation accuracy of MEMS inertial sensor errors. Then the positioning accuracy during GPS signal short outage is enhanced. To improve the positioning accuracy when a GPS signal is blocked for long time and solve the problem of the tra- ditional adaptive neuro-fuzzy inference system (ANFIS) method with poor dynamic adaptation and large calculation amount, a self-constructive ANFIS (SCANFIS) combined with the extended Kalman filter (EKF) is proposed for MEMS-INS errors modeling and predicting. Experimental road test results validate the effi- ciency of the proposed methods.展开更多
“Sula”is Toni Morrison’s second novel,which explores the pain and hardship for black women’s self-construction. It attempts to study this work from the perspective of feminism. By depicting the fate of the three t...“Sula”is Toni Morrison’s second novel,which explores the pain and hardship for black women’s self-construction. It attempts to study this work from the perspective of feminism. By depicting the fate of the three typical black women Eva, Sula and Nel, it provides meaningful ideas for the study of Sula and the way for black women to explore themselves, and also gives readers a deeper understanding of the process of black women’s self-construction and the black culture. Finally it concludes that the selfworth of black women is deeply rooted in the black culture. When pursuing independence, people should realize that self-worth and the national cultural traditions should link together deeply.展开更多
文摘Tracking precision of pre-planned trajectories is essential for an auto-guided vehicle (AGV). The purpose of this paper is to design a self-constructing wavelet neural network (SCWNN) method for dynamical modeling and control of a 2-DOF AGV. In control systems of AGVs, kinematical models have been preferred in recent research documents. However, in this paper, to enhance the trajectory tracking performance through including the AGV’s inertial effects in the control system, a learned dynamical model is replaced to the kinematical kind. As the base of a control system, the mathematical models are not preferred due to modeling uncertainties and exogenous inputs. Therefore, adaptive dynamic and control models of AGV are proposed using a four-layer SCWNN system comprising of the input, wavelet, product, and output layers. By use of the SCWNN, a robust controller against uncertainties is developed, which yields the perfect convergence of AGV to reference trajectories. Owing to the adaptive structure, the number of nodes in the layers is adjusted in online and thus the computational burden of the neural network methods is decreased. Using software simulations, the tracking performance of the proposed control system is assessed.
文摘This essay is going to read the different kinds of beings in The Lord of the Rings as different stages of man,and to analyze how they construct or destruct their selves respectively over power.The Lord of the Rings is read as a story about the self-construction and self-destruction of man,who begins to construct the sense of self from a very early stage in life,and becomes who he is in the continuous process of trying to identify himself with the image that keeps changing,of the frequently alternative construction and destruction of his self,and of intersubjectivity,the interrelation with other subjects.
基金supported by the National Natural Science Foundation of China (60902055)
文摘To improve the reliability and accuracy of the global po- sitioning system (GPS)/micro electromechanical system (MEMS)- inertial navigation system (INS) integrated navigation system, this paper proposes two different methods. Based on wavelet threshold denoising and functional coefficient autoregressive (FAR) model- ing, a combined data processing method is presented for MEMS inertial sensor, and GPS attitude information is also introduced to improve the estimation accuracy of MEMS inertial sensor errors. Then the positioning accuracy during GPS signal short outage is enhanced. To improve the positioning accuracy when a GPS signal is blocked for long time and solve the problem of the tra- ditional adaptive neuro-fuzzy inference system (ANFIS) method with poor dynamic adaptation and large calculation amount, a self-constructive ANFIS (SCANFIS) combined with the extended Kalman filter (EKF) is proposed for MEMS-INS errors modeling and predicting. Experimental road test results validate the effi- ciency of the proposed methods.
文摘“Sula”is Toni Morrison’s second novel,which explores the pain and hardship for black women’s self-construction. It attempts to study this work from the perspective of feminism. By depicting the fate of the three typical black women Eva, Sula and Nel, it provides meaningful ideas for the study of Sula and the way for black women to explore themselves, and also gives readers a deeper understanding of the process of black women’s self-construction and the black culture. Finally it concludes that the selfworth of black women is deeply rooted in the black culture. When pursuing independence, people should realize that self-worth and the national cultural traditions should link together deeply.