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Ma Y.,Xichang Satellite Launching Center | Li H.,Kunming University of Science and Technology
Pattern Recognition and Image Analysis | Year: 2014

In this paper, a new multifocus image fusion scheme based on fractional differential and NSCT is proposed. Firstly, in virtue of the properties of fractional differential, a novel focus measure in nonsubsampled contourlet transform (NSCT) domain is presented and used to determine which coefficient is from the focused region. Then, based on the imaging principle of the multifocus image and the focus measure, a new selection principle for the lowpass subbands coefficients is developed. Meanwhile, focus measure maximum choosing scheme, namely select the coefficient with maximum focus measure value as the corresponding coefficient of the fused image, is applied to the high-frequency subbands. Finally, the inverse NSCT is employed to reconstruct the fused image and a pleasing fused result is generated. The experimental results show that the proposed method outperforms the conventional multifocus image fusion methods in both subjective and objective qualities. © 2014 Pleiades Publishing, Ltd.

Hu Q.-Z.,Xichang Satellite Launching Center | Yang-Sheng Y.,Xichang Satellite Launching Center
Proceedings of 2014 Prognostics and System Health Management Conference, PHM 2014 | Year: 2014

To improve the reliability and availability, prognostics and health management technology was applied to the high pressure nitrogen system. This paper presents a multivariate state estimation techniques and sequential probability ratio test model to predict equipment health. In the approach, correlation model among monitoring parameters in normal work condition is constructed firstly. Then, according to the similarities between the current observed feature vector and each history feature vector contained in process memory matrix, estimation of the current feature vector is calculated by using MSET, and residual signal between the current feature vector and its estimation is obtained in turn. Finally, mean test and variance test for the residual signal is executed by using SPRT, and work condition of the system is pronounced. Use the realtime data to test the model, the result showed that using this method can obtain good effect. © 2014 IEEE.

Li S.-F.,Chongqing University | Li S.-F.,Xichang Satellite Launching Center | Huang X.-Y.,Chongqing University | Wei H.-B.,Xichang Satellite Launching Center
Yuhang Xuebao/Journal of Astronautics | Year: 2010

imed at space launching, the paper constructed the basic database of the geographic data and attribute data, and applied the intelligent decision-making and spatial information technology to the safety judgment for the launch. In order to monitor the real-time rocket flying status, the safety controlling channel, falling-down point, the flying parameters and flying trace were displayed on the digital map by analyzing the geographic attributes of the region surrounding the falling-down point. The paper introduced a knowledge representing model by target-rule base-feature status to support the real-time decision-making for the safety controlling of the rocket flying.

Li S.-F.,Chongqing University | Li S.-F.,Xichang Satellite Launching Center | Huang X.-Y.,Chongqing University | Che Z.-M.,Xichang Satellite Launching Center | Zhou M.,Xichang Satellite Launching Center
Yuhang Xuebao/Journal of Astronautics | Year: 2010

Aimed at the space launching, the paper combined the intelligent decision-making and the GIS technology. Based on the exploring model, fragment and the toxic gas diffusing model of liquid rocket, the diffusing ranges of the fragments and the toxic gas were provided through the visual displaying and spatial analyzing of GIS. And with the emergency database, preparedness and safety emergency model, the paper realized the simulation and analysis of the rocket flying safety. Finally, the paper utilized the CBR inference to search the most similar preparedness to support the emergency commanding.

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