The final product quality is determined by cumulation,coupling and propagation of product quality variations from all stations in multi-stage manufacturing systems(MMSs).Modeling and control of variation propagation i...The final product quality is determined by cumulation,coupling and propagation of product quality variations from all stations in multi-stage manufacturing systems(MMSs).Modeling and control of variation propagation is essential to improve product quality.However,the current stream of variations(SOV)theory can only solve the problem that a single SOV affects the product quality.Due to the existence of multiple variation streams,limited research has been done on the quality control in serial-parallel hybrid multi-stage manufacturing systems(SPH-MMSs).A state space model and its modeling strategies are developed to describe the multiple variation streams stack-up in an SPH-MMS.The SOV theory is extended to SPH-MMS.The dimensions of system model are reduced to the production-reality level,and the effect and feasibility of the model is validated by a machining case.展开更多
For real valued functions defined on Cantor triadic set, a derivative with corresponding formula of Newton Leibniz’s type is given. In particular, for the self similar functions and alternately jumping f...For real valued functions defined on Cantor triadic set, a derivative with corresponding formula of Newton Leibniz’s type is given. In particular, for the self similar functions and alternately jumping functions defined in this paper, their derivative and exceptional sets are studied accurately by using ergodic theory on Σ 2 and Duffin Schaeffer’s theorem concerning metric diophantine approximation. In addition, Haar basis of L 2(Σ 2) is constructed and Haar expansion of standard self similar function is given.展开更多
基金This project is supported by National Natural Science Foundation of China(No.50675137).
文摘The final product quality is determined by cumulation,coupling and propagation of product quality variations from all stations in multi-stage manufacturing systems(MMSs).Modeling and control of variation propagation is essential to improve product quality.However,the current stream of variations(SOV)theory can only solve the problem that a single SOV affects the product quality.Due to the existence of multiple variation streams,limited research has been done on the quality control in serial-parallel hybrid multi-stage manufacturing systems(SPH-MMSs).A state space model and its modeling strategies are developed to describe the multiple variation streams stack-up in an SPH-MMS.The SOV theory is extended to SPH-MMS.The dimensions of system model are reduced to the production-reality level,and the effect and feasibility of the model is validated by a machining case.
文摘For real valued functions defined on Cantor triadic set, a derivative with corresponding formula of Newton Leibniz’s type is given. In particular, for the self similar functions and alternately jumping functions defined in this paper, their derivative and exceptional sets are studied accurately by using ergodic theory on Σ 2 and Duffin Schaeffer’s theorem concerning metric diophantine approximation. In addition, Haar basis of L 2(Σ 2) is constructed and Haar expansion of standard self similar function is given.
