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Your search keyword '"Zhao, Wen-fang"' showing total 9 results
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9 results on '"Zhao, Wen-fang"'

4. Dynamic Analysis Helicopter Flight Simulator

Author

Hai Tao Wang, Xiao Feng Liu, Jing Wei Yu, and Zhao Wen Fang

Subjects
Engineering, Kinetic model, business.industry, General Medicine, Aerodynamics, Simulation system, Aerospace engineering, business, Flight simulator, Simulation
Abstract

For helicopter structural characteristics, this article focuses on the helicopter to take off, hover and other state aerodynamic analysis, the establishment of the fuselage-landing gear dynamics model; while the helicopter simulator simulation system are described, and the kinetic model was built simulation analysis, simulation results and the actual flight conditions consistent, indicating that the model is correct, there is a certain reference value.

Published
2014

7. The Prediction of SO2 Pollutant Concentration Using a RBF Neural Network

Author

Wang, Cheng Yuan, Zhang, Wen Yu, Wang, Ju Jie, and Zhao, Wen Fang

Abstract

Air pollution may cause pernicious effects on human health, and is a widespread problem in the world. Air quality management systems have became an important research issue with strong implications for inhabitants’ health. Monitoring and forecasting of air quality indicators plays an important role in the management systems. Artificial intelligent techniques are successfully used in modelling of highly complex and nonlinear phenomena. In this paper, a model, which is radial basis function (RBF) neural network, is established to estimate the impact of meteorological indicators on SO2. The proposed model achieves 9.91% in mean absolute percentage error (MAPE) compared to real observation data sequence. For air quality, it could be a promising candidate for forecasting the air quality indicators data sequence.

Published
2011
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8. On the Influence of Development on the Detective Quantum Efficiency and Signal-to-Noise Ratio of Photographic Materials

Author

Jen Hsin-Min and Zhao Wen-Fang

Subjects
Physics, Detective quantum efficiency, Optics, Signal-to-noise ratio, Low contrast, business.industry, General Arts and Humanities, General Physics and Astronomy, Granularity, Noise level, business, Sensitivity (electronics)
Abstract

The influence of development on the detective quantum efficiency and signal-to-noise ratio of the Kodak Spectroscopic Plate, Type lO.la–O, was studied. Five developers were used in the experiments, i.e. D–19, D–76, D–76 (1: 1). XDR–4 and POTA. It was found that developers with higher activity gave higher DQI– values and lower SNR. Development in D–19 resulted in much higher sensitivity, hut also in higher noise level (or granularity) than those obtained with other developers. A meaningful result could not be obtained with POTA due to the extremely low contrast of the developed image.

Published
1983

9. On the Method of Determination of the Noise Levels of Black-and-White Photographic Materials

Author

Jen Hsin-Min, Jiang Jiang, Liu Yu-Chen, Zhao Wen-Fang, and Lu Jing-Ti

Subjects
Work (thermodynamics), Optics, Photon, Correlation coefficient, Spots, business.industry, Chemistry, General Arts and Humanities, General Physics and Astronomy, business, Successive sampling, Noise (electronics)
Abstract

According to the recent studies on the noise characteristics of photographic materials, two kinds of noise can be defined: the macronoise, trD (mac), and the micronoise, aD (mic). The macronoise is the equivalent of the RMS-granularity of the photographic material, and is believed to include the contribution of the macroscopic non-uniformity of the emulsion layer. On the other hand, the micronoise is thought to be determined by the ultimate limits of the statistical fluctuation in the process of photon recoding on the emulsion layer. In this work, the above mentioned hypothesis was verified experimentally and also by computer simulation. The results showed that σD (mac) is generally greater than σD (mic), and the standard correlation coefficient, r, is greater than zero. This is obviously not due to the overlapping of the successive sampling spots. When the sampling rate was reduced from 50 s-l to 11 s-1 which is equivalent to increase the distance between the successive sampling spots from 52.4 m...

Published
1986

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