A method for positive polynomial validation based on polynomial decomposition is proposed to deal with control synthesis problems. Detailed algorithms for decomposition are given which mainly consider how to convert c...A method for positive polynomial validation based on polynomial decomposition is proposed to deal with control synthesis problems. Detailed algorithms for decomposition are given which mainly consider how to convert coefficients of a polynomial to a matrix with free variables. Then, the positivity of a polynomial is checked by the decomposed matrix with semidefinite programming solvers. A nonlinear control law is presented for single input polynomial systems based on the Lyapunov stability theorem. The control synthesis method is advanced to multi-input systems further. An application in attitude control is finally presented. The proposed control law achieves effective performance as illustrated by the numerical example.展开更多
Automated writing evaluation （AWE） technology is being adopted in classrooms in China and the USA. This paper presents the results of a case study of the application of AWE in Dalian, China. The quasi-experimental s...Automated writing evaluation （AWE） technology is being adopted in classrooms in China and the USA. This paper presents the results of a case study of the application of AWE in Dalian, China. The quasi-experimental study was conducted in 2010 in Chinese middle school English language classrooms. An effect size of 0.30 was found in favor of the experimental group using AWE as an online formative assessment. Student survey responses and teacher observations are presented as convergent evidence to illustrate the impact AWE technology has on teachers, students, and student achievement in English writing.展开更多
基金the National Natural Science Foundation of China (Nos. 60674028 and 60736021)the Hi-Tech Research andDevelopment Program (863) of China (Nos. 2006AA04Z184 and 2007AA041406)+1 种基金the Key Technologies R&D Program of Zhejiang Province, China (No. 2006C11066)the Joint Funds of NSFC-Guangdong Province of China (No. U0735003)
文摘A method for positive polynomial validation based on polynomial decomposition is proposed to deal with control synthesis problems. Detailed algorithms for decomposition are given which mainly consider how to convert coefficients of a polynomial to a matrix with free variables. Then, the positivity of a polynomial is checked by the decomposed matrix with semidefinite programming solvers. A nonlinear control law is presented for single input polynomial systems based on the Lyapunov stability theorem. The control synthesis method is advanced to multi-input systems further. An application in attitude control is finally presented. The proposed control law achieves effective performance as illustrated by the numerical example.
文摘Automated writing evaluation （AWE） technology is being adopted in classrooms in China and the USA. This paper presents the results of a case study of the application of AWE in Dalian, China. The quasi-experimental study was conducted in 2010 in Chinese middle school English language classrooms. An effect size of 0.30 was found in favor of the experimental group using AWE as an online formative assessment. Student survey responses and teacher observations are presented as convergent evidence to illustrate the impact AWE technology has on teachers, students, and student achievement in English writing.
