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	Development of in-situ anisotropic deformation characteristics detection equipment for loess hole 期刊论文 OAI收割 MEASUREMENT, 2025, 卷号: 243, 页码: 18 作者: Zhang, Yaozhong; Zhang, Hongbing; Yan, Changgen; Lan, Hengxing; Liu, Xin \| 收藏 \| 浏览/下载：10/0 \| 提交时间：2025/03/03 Anisotropic parameter detection Equipment development Precision calibration Field performance test
	Efficient rate control technique for CCSDS image encoding (EI CONFERENCE) 会议论文 OAI收割 IEEE 2nd International Conference on Computing, Control and Industrial Engineering, CCIE 2011, August 20, 2011 - August 21, 2011, Wuhan, China Jin L. 收藏 \| 浏览/下载：91/0 \| 提交时间：2013/03/25 For the limitation of data transmission bandwidth and real time transmission demand generally image compression is required to implement the precise and flexible rate control algorithm. Rate control is an important issue in the image compression field. This paper considers the problem of rate allocation to each encoded segment for CCSDS image compression. One straightforward method is to allocate an equal amount of rate to each segment based on the average of the total number of compressed bytes. The obvious drawback of this method is that different segment will be reconstructed to different quality so the overall quality of the reconstructed image will not be optimized. For the shortage of the original rate control method as to improve the overall quality of the reconstructed image an improved rate control algorithm is proposed for CCSDS image encoding. The key component of the proposed rate control method is the appropriate rate allocation. Experiments on the test images show that the PSNR can be increased at about 0.3dB on average compared to the original algorithm. Therefore experimental results confirm the effectiveness of the proposed algorithm in terms of objective evaluation and the rate-distortion performance of the reconstructed image is improved. 2011 IEEE.
	Modular aircraft simulation platform based on simulink (EI CONFERENCE) 会议论文 OAI收割 2010 IEEE International Conference on Mechatronics and Automation, ICMA 2010, August 4, 2010 - August 7, 2010, Xi'an, China Chen C.-Q.; Ji Y. 收藏 \| 浏览/下载：24/0 \| 提交时间：2013/03/25 Aircraft simulation platform is the most important supporting technology in the aircraft development process. This simulation platform can be used for validating the design of subsystem and also it provides the necessary data for the Aircraft design. Wind has great impact on the flight parameter. In order to accurately simulate the wind model and calculate the flight parameters a simulation modeling method for flight parameter simulation platform under wind field environment is established. Firstly the various sub-systems which affecting flight parameters are analyzed some mathematical models of the flight parameter simulation platform is established. Secondly the atmospheric wind field is studied to analyze the impact on its trajectory. Then the model is built in the Simulink toolbox in the Matlab which is based on the principles of hierarchy and modularity using C MEX S-function for the complex kinetic equations. Finally when the models have been established encapsulating models for several subsystem and assembling them for the Aircraft simulation platform based on the unified interface. The simulation tests (including the performance test of a certain gliding Aircraft the wind influence test of a certain uncontrolled aircraft) prove the simulation capability of the platform and its calculating step can reach 1 ms. Comparing simulation with field test data of a certain uncontrolled aircraft it shows that the relative deviation of range is 0.47% the relative deviation of maximal altitude is 2.1%. Taking relevant standards as a reference standard it is demonstrated the platform is reliable meets the engineering accuracy requirements. 2010 IEEE.