Compared to BP algorithm,it can be applied without the need of backward propagating the error throughout a feedback network. This important property makes it possible to design the simple neural network controller directly.

An accurate model was used to predict the gain, saturation and noise characteristics of ytterbium doped fiber amplifiers (YDFA), pumped at λ p=910 nm. It was shown that the strong backward propagating ASE around 975 nm could dramatically increase the NF and limit the gain available at longer wavelength.

In the paper, the author made up artifical neural network computer program by means of utilizing forward multy-layer neural theory and adopting error backward propagating method, and applied artificial neural network to the design of propeller.

Plenty of samples is provided for training BP neural network by traditional design method and the topology structure is built using forward propagating data and backward propagating error data,which is applied to optimal design of parallel double broken line pulley in order to accomplish the mapping between main parameter of hoisting mechanism of gantry crane and the related parameters of parallel double broken line pulley. This is a new way to design key parts of crane featuring good design quality and high design efficiency.

The isolator suppresses the backward propagating amplified spontaneous emission and improves the gain and noise characteristics as well as the output signal power characteristics. It is shown that the gain improvement of about 5dB and the NF reduction of 1.6dB are expected.

The rate equation model is setup for analyzing two-stage erbium-doped fiber amplifiers (EDFA) . The isolator within EDFA suppresses the backward propagating amplified spontaneous emission and improves the gain and noise characteristics as well as the output signal power characteristics. The results show that the small signal gain can be increased 3dB, the noise coefficient has been decreased 1.0dB, nearly to quantum level.

The results show that the signal gain and noise figure are obviously improved due to the effective suppression of backward propagating amplified spontaneous emission (ASE) noise and the resulting consumption reduction of reversed particles by the isolator.

Forward and backward propagating peristaltic waves were invoked in two other unconscious dogs, indicating that the recreation of colonic peristalsis under microprocessor control is feasible.

Several types of behavior can be detected in addition to the normal backward propagating waves of about 2 Hz that propel untethered worms forward.

A WKB solution of the problem predicts a backward propagating wave on account of the self-induced inhomogeneity.

Simulations performed with this model reproduce experimental phenomena observed in traffic such as free flow, synchronized flow, congested flow, lane inversion, forward and backward propagating waves.

The out-coupling angle a = 34 indicates that backward propagating QPM using the CC-SW grating is realized.

The effect of energy dependence (ED) of the G matrix on RPA is investigated. Using the Hamada-Johnston potential, we calculate the 1p-1h TDA and RPA spectra of ~(16)O. The following four cases are considered: (1) every G matrix element is approximated by its on shell value, (2) ED of G is taken intoaccount rigorously, (3) the effect of self-screening (SC) is considered, but the G matrix elements are assumed on the energy shell, (4) both SC and ED of G are taken into account. It is found that ED of G indeed causes...

The effect of energy dependence (ED) of the G matrix on RPA is investigated. Using the Hamada-Johnston potential, we calculate the 1p-1h TDA and RPA spectra of ~(16)O. The following four cases are considered: (1) every G matrix element is approximated by its on shell value, (2) ED of G is taken intoaccount rigorously, (3) the effect of self-screening (SC) is considered, but the G matrix elements are assumed on the energy shell, (4) both SC and ED of G are taken into account. It is found that ED of G indeed causes a substantial damping effect on the backward-propagating bubbles of RPA as suggested by Wu. Further, ED of G and SC work in the same direction to diminish the difference between the energy spectra calculated by TDA and RPA.

Numerical simulation of propagation of rotor / stator interaction noise in turbofan exhaust duct which is assumed to be made up of annular ducts with axially segmented treatments is developed by the mode analysis method. By quantitatively predicting the change of the mode coefficient distribution of forward and backward propagating acoustic energy at the segment interfaces, the attenuation of interaction noise is also investigated. The results manifest that when the forward travelling sound waves pass...

Numerical simulation of propagation of rotor / stator interaction noise in turbofan exhaust duct which is assumed to be made up of annular ducts with axially segmented treatments is developed by the mode analysis method. By quantitatively predicting the change of the mode coefficient distribution of forward and backward propagating acoustic energy at the segment interfaces, the attenuation of interaction noise is also investigated. The results manifest that when the forward travelling sound waves pass through the admittance discontinuity planes, the modal reflection will increase and the forward modes of waves will decrease. So the modal reflection at the interfaces can be utilized to suppress propagation of the in-duct noise. In addition, the effects of the change of resistance and reactance of liners on the suppression are theoretically calculated. It can be concluded that in the presence of high frequency source and high Mach number flow, whether for the change of resistance or for the change of reactance, there exist local peak values and fluctuation of the in-duct suppression, and at this moment, the monotonicity of suppression with the change of resistance and of reactance will no longer come into existence. Therefore, it is necessary for the engine noise reduction to choose adequate impedance of liners.

Using a set of traveling wave rate equations,a superluminescent diode with a low facet reflectivity is studied. Analytical expressions of the distributions of carrier density,forward- and backward-propagating photon densities,and gain are obtained at different facet reflectivities.It is shown that the high nonuniform carrier distribution is evident in the case of low facet reflectivity.The results can serve as useful guides in understanding emission mechanism of superluminescent diodes.