The combined quadratic orthogonal regression method of experiment design wasemployed to explore the effects of process parameters of plasma nitriding of tantalum such as totalpressure, temperature and original hydroge...The combined quadratic orthogonal regression method of experiment design wasemployed to explore the effects of process parameters of plasma nitriding of tantalum such as totalpressure, temperature and original hydrogen molar fraction on the hardness, roughness and structureof nitriding surfaces. The regression equations of hardness, roughness and structure were givenaccording to the results of regression and statistic analysis. And the diffusion activation energyof nitrogen in tantalum on plasma nitriding conditions was calculated according to the experimentaldata of hardness of plasma-nitriding of tantalum vs time and temperature. The diffusion activationenergy calculated belongs to (155.49 +- 10.51) kJ/mol (783-983 K).展开更多
This study uses multiple regression to investigate the effects of Land and building use on popuLation, Land price, and passengers. Initialty, we abstract annuat data on Land and buildings usage within a radius of 0 m-...This study uses multiple regression to investigate the effects of Land and building use on popuLation, Land price, and passengers. Initialty, we abstract annuat data on Land and buildings usage within a radius of 0 m-400 m for railway stations and 400 m-800 m for subway stations in Fukuoka, Japan by using the GIS. We then analyze the relationships between 13 factors of rand use and 8 factors of building usage, as well as the related poputation, Land price, and passengers using the quantitative expression method. Using several categories of land use and building usage as explanatory variables, we anatyze the degree to which the selected categories affect population, Land price, and passengers by using the muttiple regression method. This research can aid the further development of land and buitding usage in the future.展开更多
文摘The combined quadratic orthogonal regression method of experiment design wasemployed to explore the effects of process parameters of plasma nitriding of tantalum such as totalpressure, temperature and original hydrogen molar fraction on the hardness, roughness and structureof nitriding surfaces. The regression equations of hardness, roughness and structure were givenaccording to the results of regression and statistic analysis. And the diffusion activation energyof nitrogen in tantalum on plasma nitriding conditions was calculated according to the experimentaldata of hardness of plasma-nitriding of tantalum vs time and temperature. The diffusion activationenergy calculated belongs to (155.49 +- 10.51) kJ/mol (783-983 K).
文摘This study uses multiple regression to investigate the effects of Land and building use on popuLation, Land price, and passengers. Initialty, we abstract annuat data on Land and buildings usage within a radius of 0 m-400 m for railway stations and 400 m-800 m for subway stations in Fukuoka, Japan by using the GIS. We then analyze the relationships between 13 factors of rand use and 8 factors of building usage, as well as the related poputation, Land price, and passengers using the quantitative expression method. Using several categories of land use and building usage as explanatory variables, we anatyze the degree to which the selected categories affect population, Land price, and passengers by using the muttiple regression method. This research can aid the further development of land and buitding usage in the future.