Two-mode circular states,which are superposition states from some two-mode coherent states,are studiedtheoretically.It is shown that under certain conditions two-mode circular states may exhibit nonclassical effects,s...Two-mode circular states,which are superposition states from some two-mode coherent states,are studiedtheoretically.It is shown that under certain conditions two-mode circular states may exhibit nonclassical effects,suchas sub-Poissonian statistics and intermode correlation.We propose schemes to generate two-mode circular states by theinteraction of a trapped ion with traveling wave lasers.展开更多
The purpose of the study was to use the Problem-Centered Double-Cycles Instructional Model （PCDC-IM） （1995, Chang） to help the teacher （Lin） implement model-eliciting activity （MEA） in her mathematics classes....The purpose of the study was to use the Problem-Centered Double-Cycles Instructional Model （PCDC-IM） （1995, Chang） to help the teacher （Lin） implement model-eliciting activity （MEA） in her mathematics classes. In this study, there were 31 students divided in 10 groups and engaged in the MEA ＂Who saved the oriental cherry trees＂. Data collections included the learning sheets, journals and debriefing forms of students, teaching and reflection journals, observation reports, and field notes of teachers, reflection journals and interview reports of researchers, video tapes and records of the classes and meetings. There were four parts of the teaching cycle in PCDC-IM, namely task, guidance, environment and analysis. We summarized developing and implementing the MEA in ＂Task＂ aspect, 5 principles and 5 kinds of teachers＇ roles in ＂Guidance＂ aspect, 2 elements and 5 features in ＂Environment＂ aspect and data in ＂Analysis＂ aspect. The findings showed that PCDC-IM was helpful for mathematics teachers who want to change their instruction from lecture into modeling teaching.展开更多
基金supported by the Natural Science Foundation of the Education Committee of Anhui Province of China under Grant No.JK2008A029
文摘Two-mode circular states,which are superposition states from some two-mode coherent states,are studiedtheoretically.It is shown that under certain conditions two-mode circular states may exhibit nonclassical effects,suchas sub-Poissonian statistics and intermode correlation.We propose schemes to generate two-mode circular states by theinteraction of a trapped ion with traveling wave lasers.
文摘The purpose of the study was to use the Problem-Centered Double-Cycles Instructional Model （PCDC-IM） （1995, Chang） to help the teacher （Lin） implement model-eliciting activity （MEA） in her mathematics classes. In this study, there were 31 students divided in 10 groups and engaged in the MEA ＂Who saved the oriental cherry trees＂. Data collections included the learning sheets, journals and debriefing forms of students, teaching and reflection journals, observation reports, and field notes of teachers, reflection journals and interview reports of researchers, video tapes and records of the classes and meetings. There were four parts of the teaching cycle in PCDC-IM, namely task, guidance, environment and analysis. We summarized developing and implementing the MEA in ＂Task＂ aspect, 5 principles and 5 kinds of teachers＇ roles in ＂Guidance＂ aspect, 2 elements and 5 features in ＂Environment＂ aspect and data in ＂Analysis＂ aspect. The findings showed that PCDC-IM was helpful for mathematics teachers who want to change their instruction from lecture into modeling teaching.
