本文研究了两变量函数 f(x,y)用单变量函数 g(x)作混合范数逼近问题,即求g~*(x)∈G,G 是一 Haar 子空间,使(?)integral from Y|f(x,y)-g~*(x)|dμ=(?)integral from Y|f((?),y)-g(x)|dμ我们建立了包括交错定理、de la Vallee Poussin ...本文研究了两变量函数 f(x,y)用单变量函数 g(x)作混合范数逼近问题,即求g~*(x)∈G,G 是一 Haar 子空间,使(?)integral from Y|f(x,y)-g~*(x)|dμ=(?)integral from Y|f((?),y)-g(x)|dμ我们建立了包括交错定理、de la Vallee Poussin 定理、唯一性定理和强唯一性定理在内的 Chebyshev 逼近理论。展开更多
This paper analyzes current status of teachers' speaking test, applies presently mature C/S system structure and oilers a network way for teachers' speaking exam. We provide the whole process of design and developme...This paper analyzes current status of teachers' speaking test, applies presently mature C/S system structure and oilers a network way for teachers' speaking exam. We provide the whole process of design and development in online speaking exam, illustrate several functional designs including item bank construction, auto-generating examination paper and test paper analysis and discuss various network programming development technology during teachers' speaking network examination intensively. Directed by software engineering theory, the system is finally designed and realized through feasible research, requirement analysis, general design, detailed design, and tests with popular system development language and powerful database management.展开更多
文摘本文研究了两变量函数 f(x,y)用单变量函数 g(x)作混合范数逼近问题,即求g~*(x)∈G,G 是一 Haar 子空间,使(?)integral from Y|f(x,y)-g~*(x)|dμ=(?)integral from Y|f((?),y)-g(x)|dμ我们建立了包括交错定理、de la Vallee Poussin 定理、唯一性定理和强唯一性定理在内的 Chebyshev 逼近理论。
文摘This paper analyzes current status of teachers' speaking test, applies presently mature C/S system structure and oilers a network way for teachers' speaking exam. We provide the whole process of design and development in online speaking exam, illustrate several functional designs including item bank construction, auto-generating examination paper and test paper analysis and discuss various network programming development technology during teachers' speaking network examination intensively. Directed by software engineering theory, the system is finally designed and realized through feasible research, requirement analysis, general design, detailed design, and tests with popular system development language and powerful database management.