A novel fiber optic liquid level sensor based on laser radar (ladar) is reported here. Using the perfect technique of ladar in which the phase of amplitude modulated light wave reflected from the liquid surface is com...A novel fiber optic liquid level sensor based on laser radar (ladar) is reported here. Using the perfect technique of ladar in which the phase of amplitude modulated light wave reflected from the liquid surface is compared with that of original modulation signal, the distance can be measured precisely. A special symmetric compensating coaxial optical system is proposed to eliminate many adverse effects. It realized the one-time electronic-free optical measurement on a simulated oil tank and achieves an accuracy of 0.3%, within a temperature range of -10 ℃～+40 ℃ over a measuring of 0～10 m.展开更多
This paper uses the literature method to analyze the changes of preschool physical education policy, curriculum, teachers, activity venues and facilities in the late Qing Dynasty and the early Republic of China. It is...This paper uses the literature method to analyze the changes of preschool physical education policy, curriculum, teachers, activity venues and facilities in the late Qing Dynasty and the early Republic of China. It is pointed out that it originated in the Mongolian nursing home, imitated the Japanese education system, and introduced the teaching model of the western modern early childrens movement, so as to replace the traditional teaching system in China. This point is of great practical significance to promote the modernization of early physical education teaching in China, promote foreign advanced childrens physical education teaching, and improve the construction of teachers in China.展开更多
With the national governments attention to physical education and the issuance of a series of policy documents in recent years, the practical problems of physical education curriculum and teaching in Chinas colleges a...With the national governments attention to physical education and the issuance of a series of policy documents in recent years, the practical problems of physical education curriculum and teaching in Chinas colleges and universities have become more and more obvious, which is mainly manifested in the fact that knowledge-based teaching is far from the needs of real life;Marginalized, ignoring the concept of lifelong sports;The inheritance of education weakens the students dominant position. Based on these practical problems, it is necessary to make the physical education curriculum and teaching in our countrys colleges and universities vivid. This is the need for the development of the physical education class program in colleges and universities;It is the need of peoples all-round development and self-realization;Is the inevitable requirement of social and economic development;It is an inevitable requirement for the strategic transfer of Chinas sports development. If the physical education curriculum and teaching in colleges and universities want to be truly life-oriented, it is necessary to change the teaching guiding ideology;Updating the curriculum system and content;Enrich the curriculum teaching objectives and evaluation system.展开更多
文摘A novel fiber optic liquid level sensor based on laser radar (ladar) is reported here. Using the perfect technique of ladar in which the phase of amplitude modulated light wave reflected from the liquid surface is compared with that of original modulation signal, the distance can be measured precisely. A special symmetric compensating coaxial optical system is proposed to eliminate many adverse effects. It realized the one-time electronic-free optical measurement on a simulated oil tank and achieves an accuracy of 0.3%, within a temperature range of -10 ℃～+40 ℃ over a measuring of 0～10 m.
文摘This paper uses the literature method to analyze the changes of preschool physical education policy, curriculum, teachers, activity venues and facilities in the late Qing Dynasty and the early Republic of China. It is pointed out that it originated in the Mongolian nursing home, imitated the Japanese education system, and introduced the teaching model of the western modern early childrens movement, so as to replace the traditional teaching system in China. This point is of great practical significance to promote the modernization of early physical education teaching in China, promote foreign advanced childrens physical education teaching, and improve the construction of teachers in China.
文摘With the national governments attention to physical education and the issuance of a series of policy documents in recent years, the practical problems of physical education curriculum and teaching in Chinas colleges and universities have become more and more obvious, which is mainly manifested in the fact that knowledge-based teaching is far from the needs of real life;Marginalized, ignoring the concept of lifelong sports;The inheritance of education weakens the students dominant position. Based on these practical problems, it is necessary to make the physical education curriculum and teaching in our countrys colleges and universities vivid. This is the need for the development of the physical education class program in colleges and universities;It is the need of peoples all-round development and self-realization;Is the inevitable requirement of social and economic development;It is an inevitable requirement for the strategic transfer of Chinas sports development. If the physical education curriculum and teaching in colleges and universities want to be truly life-oriented, it is necessary to change the teaching guiding ideology;Updating the curriculum system and content;Enrich the curriculum teaching objectives and evaluation system.
