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The milling of titanium alloy thin-walled parts is confronted with the double challenges of hard to machined materials and hard machined structures. Aiming at the problem that the effect of the damping process is significant and difficult to measure in the process of machining titanium thin-walled parts, the mathematical model of the process damping is established. The tangential and radial ploughing force coefficients that characterize the damping of the process are obtained based on the power spectral density matrix and the principle of energy balance. The structural dynamic modification method is used to solve the nonlinear problem of the workpiece characteristics with the material removal and the change of the relative position of the tool and the workpiece. The time delay differential equation which considers the damping effect of the process and the dynamic characteristic of the workpiece is solved by the full-discretization method, and the three-dimensional stability lobe diagram of the milling thin-walled parts is obtained. A series of experiments have been conducted to verify the accuracy of the stability prediction., QC 20181031

A consistent theory of optimum subband coding of zero mean wide-sense cyclostationary signals with N-periodic statistics is presented in this paper. Blocked polyphase representation of the analysis and synthesis filter banks is introduced as an effective way of multirate subband coder description. Optimum energy compaction using Nyquist-M process is presented as a solution for maximizing the coding gain of the coder. In two definitions and four theorems the author proves that Nyquist-M filters fulfill necessary and sufficient conditions imposed on subband signals. Results from Matlab simulations are presented to support theoretical conclusions.

A consistent theory of optimum subband coding of zero mean wide-sense cyclostationary signals with N-periodic statistics is presented in this paper. Blocked polyphase representation of the analysis and synthesis filter banks is introduced as an effective way of multirate subband coder description. Optimum energy compaction using Nyquist-M process is presented as a solution for maximizing the coding gain of the coder. In two definitions and four theorems the author proves that Nyquist-M filters fulfill necessary and sufficient conditions imposed on subband signals. Results from Matlab simulations are presented to support theoretical conclusions.

A consistent theory of optimum subband coding of zero mean wide-sense cyclostationary signals with N-periodic statistics is presented in this paper. Blocked polyphase representation of the analysis and synthesis filter banks is introduced as an effective way of multirate subband coder description. Optimum energy compaction using Nyquist-M process is presented as a solution for maximizing the coding gain of the coder. In two definitions and four theorems the author proves that Nyquist-M filters fulfill necessary and sufficient conditions imposed on subband signals. Results from Matlab simulations are presented to support theoretical conclusions.

A consistent theory of optimum subband coding of zero mean wide-sense cyclostationary signals with N-periodic statistics is presented in this paper. Blocked polyphase representation of the analysis and synthesis filter banks is introduced as an effective way of multirate subband coder description. Optimum energy compaction using Nyquist-M process is presented as a solution for maximizing the coding gain of the coder. In two definitions and four theorems the author proves that Nyquist-M filters fulfill necessary and sufficient conditions imposed on subband signals. Results from Matlab simulations are presented to support theoretical conclusions.

A consistent theory of optimal subband coding of zero mean wide-sense cyclostationary signals, with N-periodic statistics, is presented in this article. An M-channel orthonormal uniform filter bank, employing N-periodic analysis and synthesis filters, is used while an average variance condition is applied to evaluate the output distortion. In three lemmas and final theorem, the necessity of decorrelation of blocked subband signals and requirement of specific ordering of power spectral densities are proven.

A consistent theory of optimal subband coding of zero mean wide-sense cyclostationary signals, with N-periodic statistics, is presented in this article. An M-channel orthonormal uniform filter bank, employing N-periodic analysis and synthesis filters, is used while an average variance condition is applied to evaluate the output distortion. In three lemmas and final theorem, the necessity of decorrelation of blocked subband signals and requirement of specific ordering of power spectral densities are proven.

A consistent theory of optimal subband coding of zero mean wide-sense cyclostationary signals, with N-periodic statistics, is presented in this article. An M-channel orthonormal uniform filter bank, employing N-periodic analysis and synthesis filters, is used while an average variance condition is applied to evaluate the output distortion. In three lemmas and final theorem, the necessity of decorrelation of blocked subband signals and requirement of specific ordering of power spectral densities are proven.