Three kinds of high-alumina repairing mixes for medium-frequency induction furnace were prepared by ramming method with sodium silicate, phosphoric acid and aluminium dihydrogen phosphate as binder, respectively. Phys...Three kinds of high-alumina repairing mixes for medium-frequency induction furnace were prepared by ramming method with sodium silicate, phosphoric acid and aluminium dihydrogen phosphate as binder, respectively. Physical properties of the specimens heat treated at different temperatures were tested and compared. The results show that the specimen bonded by sodium silicate behaves much higher strength after fired at 1 600 ℃ compared with the specimen, bonded by phosphoric acid or aluminium dihydrogen phosphate. Due to more liquid phase formation the properties of specimen bonded by sodium silicate are poor with a low strength and a large volume shrinkage at high temperatures. Meanwhile. the speeimen bonded by phosphoric acid and aluminium dihydrogen phosphate, respectively, show relatively high strengths and slight volume expansions at high temperatures because of in-situ mullite formation.展开更多
Mixed-effects models,also called random-effects models,are a regression type of analysis which enables the analyst to not only describe the trend over time within each subject,but also to describe the variation among ...Mixed-effects models,also called random-effects models,are a regression type of analysis which enables the analyst to not only describe the trend over time within each subject,but also to describe the variation among different subjects.Nonlinear mixed-effects models provide a powerful and flexible tool for handling the unbalanced count data.In this paper,nonlinear mixed-effects models are used to analyze the failure data from a repairable system with multiple copies.By using this type of models,statistical inferences about the population and all copies can be made when accounting for copy-to-copy variance.Results of fitting nonlinear mixed-effects models to nine failure-data sets show that the nonlinear mixed-effects models provide a useful tool for analyzing the failure data from multi-copy repairable systems.展开更多
文摘Three kinds of high-alumina repairing mixes for medium-frequency induction furnace were prepared by ramming method with sodium silicate, phosphoric acid and aluminium dihydrogen phosphate as binder, respectively. Physical properties of the specimens heat treated at different temperatures were tested and compared. The results show that the specimen bonded by sodium silicate behaves much higher strength after fired at 1 600 ℃ compared with the specimen, bonded by phosphoric acid or aluminium dihydrogen phosphate. Due to more liquid phase formation the properties of specimen bonded by sodium silicate are poor with a low strength and a large volume shrinkage at high temperatures. Meanwhile. the speeimen bonded by phosphoric acid and aluminium dihydrogen phosphate, respectively, show relatively high strengths and slight volume expansions at high temperatures because of in-situ mullite formation.
文摘Mixed-effects models,also called random-effects models,are a regression type of analysis which enables the analyst to not only describe the trend over time within each subject,but also to describe the variation among different subjects.Nonlinear mixed-effects models provide a powerful and flexible tool for handling the unbalanced count data.In this paper,nonlinear mixed-effects models are used to analyze the failure data from a repairable system with multiple copies.By using this type of models,statistical inferences about the population and all copies can be made when accounting for copy-to-copy variance.Results of fitting nonlinear mixed-effects models to nine failure-data sets show that the nonlinear mixed-effects models provide a useful tool for analyzing the failure data from multi-copy repairable systems.
