中国科学院机构知识库网格系统: 检索

A Coupled Hydrologic-Hydraulic Model (XAJ-HiPIMS) for Flood Simulation 期刊论文 OAI收割
WATER, 2020, 卷号: 12, 期号: 5, 页码: 12
作者: Wang, Yueling; Yang, Xiaoliu

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收藏 | 浏览/下载：55/0 | 提交时间：2021/03/18

Xinanjiang model high-performance integrated hydraulic modelling system (HiPIMS) coupled hydrologic-hydraulic model two-dimensional surface confluence calculation over basin

Applications of differential barometric altimeter in ground cellular communication positioning network 期刊论文 OAI收割
IET SCIENCE MEASUREMENT & TECHNOLOGY, 2020, 卷号: 14, 期号: 3, 页码: 322-331
作者: Hu, Zhengqun; Zhang, Lirong; Ji, Yuanfa

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收藏 | 浏览/下载：26/0 | 提交时间：2021/12/06

cellular radio height measurement measurement errors Global Positioning System altimeters barometers least squares approximations Kalman filters surface fitting spread spectrum communication compensation matrix algebra GPS signal message structure power spectrum spread spectrum ranging signal fitting parameters least-square solution calibration compensation system noise variance matrix measurement noise variance matrix multibase station correction height information correction calculation DBA system systematic performance differential barometric altimeter ground cellular communication positioning network measurement datum distribution altitude positioning error Global Positioning System differential barometric altimetry system systematic implementation level continuous altitude measurement precise altitude measurement DBA systematic implementation aspect two dimensional curved surface fitting function sensor measurement correction filtering effect Kalman filter measuring station multiBSs navigation fusion

A Coupled Hydrologic-Hydraulic Model (XAJ-HiPIMS) for Flood Simulation 期刊论文 OAI收割
WATER, 2020, 卷号: 12, 期号: 5, 页码: 12
作者: Wang, Yueling; Yang, Xiaoliu

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收藏 | 浏览/下载：15/0 | 提交时间：2021/03/18

Xinanjiang model high-performance integrated hydraulic modelling system (HiPIMS) coupled hydrologic-hydraulic model two-dimensional surface confluence calculation over basin

A Performance Analysis Method of High Speed and Small Diameter Propeller 会议论文 OAI收割
Melbourne, VIC, Australia, September 15-16, 2018
作者: Zhang YC(张宇川); Hu ZQ(胡志强); Yang Y(杨翊); Geng LB(耿令波); Wang C(王超)

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收藏 | 浏览/下载：14/0 | 提交时间：2019/04/13

Performance calculation Propeller Strip theory MATLAB

Radical recombination in a hydrocarbon-fueled scramjet nozzle 期刊论文 OAI收割
Chinese Journal of Aeronautics, 2014, 卷号: 27, 期号: 6, 页码: 1413-1420
作者: Zhang XY(张晓源); Qin LZ; Chen H(陈宏); He XZ

收藏 | 浏览/下载：33/0 | 提交时间：2015/03/11

Chemical reactions Nozzles Performance calculation Radical Recombination

On hyperspectral remotely sensed image classification based on MNF and AdaBoosting (EI CONFERENCE) 会议论文 OAI收割
2012 3rd IEEE/IET International Conference on Audio, Language and Image Processing, ICALIP 2012, July 16, 2012 - July 18, 2012, Shanghai, China
作者: Yu P.; Yu P.; Gao X.

收藏 | 浏览/下载：23/0 | 提交时间：2013/03/25

As an effective statistical learning tool AdaBoosting has been widely used in the field of pattern recognition. In this paper a new method is proposed to improve the classification performance of hyperspectral images by combining the minimum noise fraction (MNF) and AdaBoosting. Because the hyperspectral imagery has many bands which have strong correlation and high redundancy the hyperspectral data are pre-processed by the minimum noise fraction to reduce the data's dimensionality whilst to remove noise bands simultaneously. Then we use an AdaBoost algorithm to conduct the classification of hyperspectral remotely sensed image. Experimental results show that the classification accuracy is improved and the time of calculation is reduced as well. 2012 IEEE.

An improved hyperspectral classification algorithm based on back-propagation neural networks (EI CONFERENCE) 会议论文 OAI收割
2012 2nd International Conference on Remote Sensing, Environment and Transportation Engineering, RSETE 2012, June 1, 2012 - June 3, 2012, Nanjing, China
作者: Yu P.; Yu P.

收藏 | 浏览/下载：34/0 | 提交时间：2013/03/25

In this paper a new method is proposed to improve the classification performance of hyperspectral images by combining the principal component analysis (PCA) genetic algorithm (GA) and artificial neural networks (ANNs). First some characteristics of the hyperspectral remotely sensed data such as high correlation high redundancy etc. are investigated. Based on the above analysis we propose to use the principal component analysis to capture the main information existing in the hyperspectral images and reduce its dimensionality consequently. Next we use neural networks to classify the reduced hyperspectral data. Since the back-propagation neural network we used is easy to suffer from the local minimum problem we adopt a genetic algorithm to optimize the BP network's weights and the threshold. Experimental results show that the classification accuracy is improved and the time of calculation is reduced as well. 2012 IEEE.

A parallel algorithm for medical images registration based on B-splines (EI CONFERENCE) 会议论文 OAI收割
4th International Congress on Image and Signal Processing, CISP 2011, October 15, 2011 - October 17, 2011, Shanghai, China
作者: Zhang T.

收藏 | 浏览/下载：26/0 | 提交时间：2013/03/25

Cubic B-splines is widely applied in non-rigid registration because of its approximation performance and fast computational characteristics. However a small scale non-rigid deformation is needed to characterize by a large number of control points. Moreover an iterative optimization strategy of the non-rigid registration algorithm and the normalized mutual information (NMI) cost a great quantity calculation. So the process of the non-rigid registration is slowed by calculations of NMI in a iterative optimization strategy. In this paper a parallel optimization algorithm based on cubic B-splines functions is proposed to parallelize the optimization algorithm of the nonrigid registration and the calculations of normalize mutual information. In practice a fast algorithm of cubic B-splines is used and the control points are only distributed on the targets. Experiments show that the use of the fast algorithm and the parallel optimization strategy improves the non-rigid registration process of medical images. 2011 IEEE.

The new approach for infrared target tracking based on the particle filter algorithm (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Sun H.; Han H.-X.; Sun H.

收藏 | 浏览/下载：60/0 | 提交时间：2013/03/25

Target tracking on the complex background in the infrared image sequence is hot research field. It provides the important basis in some fields such as video monitoring precision and video compression human-computer interaction. As a typical algorithms in the target tracking framework based on filtering and data connection the particle filter with non-parameter estimation characteristic have ability to deal with nonlinear and non-Gaussian problems so it were widely used. There are various forms of density in the particle filter algorithm to make it valid when target occlusion occurred or recover tracking back from failure in track procedure but in order to capture the change of the state space it need a certain amount of particles to ensure samples is enough and this number will increase in accompany with dimension and increase exponentially this led to the increased amount of calculation is presented. In this paper particle filter algorithm and the Mean shift will be combined. Aiming at deficiencies of the classic mean shift Tracking algorithm easily trapped into local minima and Unable to get global optimal under the complex background. From these two perspectives that "adaptive multiple information fusion" and "with particle filter framework combining" we expand the classic Mean Shift tracking framework.Based on the previous perspective we proposed an improved Mean Shift infrared target tracking algorithm based on multiple information fusion. In the analysis of the infrared characteristics of target basis Algorithm firstly extracted target gray and edge character and Proposed to guide the above two characteristics by the moving of the target information thus we can get new sports guide grayscale characteristics and motion guide border feature. Then proposes a new adaptive fusion mechanism used these two new information adaptive to integrate into the Mean Shift tracking framework. Finally we designed a kind of automatic target model updating strategy to further improve tracking performance. Experimental results show that this algorithm can compensate shortcoming of the particle filter has too much computation and can effectively overcome the fault that mean shift is easy to fall into local extreme value instead of global maximum value.Last because of the gray and fusion target motion information this approach also inhibit interference from the background ultimately improve the stability and the real-time of the target track. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

Evaluation of the operating range for ground-based infrared imaging tracking system (EI CONFERENCE) 会议论文 OAI收割
International Symposium on Photoelectronic Detection and Imaging 2011: Advances in Infrared Imaging and Applications, May 24, 2011 - May 24, 2011, Beijing, China
作者: Zhang Z.-D.

收藏 | 浏览/下载：49/0 | 提交时间：2013/03/25

Ground-based infrared imaging tracking system (GIITS) is of great importance for aerial target warning and guard. The operating range is one of the key performance specifications on the other which should be calculated calculate the radiation power received on the detector in order to analysis whether the output signal meets the detection requirements or not analyzed and studied during the whole GIITS design process. The operating range is mostly influenced by a few factors without considering the effect of the background radiation. By improving of the traditional method including atmospheric attenuation a new operating range calculation model of the GIITS was established based on two requirements. One is that the image size of observed target should meet the requirement of the processor signal extraction. The number of the pixel occupied by target image should be more than 9. The other is that the signal noise ratio (SNR) of the GIITS should not be less than 5 to meet the requirements of the target detection probability and spatial frequency. The SNR calculation equation in form of energy is deduced and the radiation characteristic of the observed target and background are analyzed. When evaluate the operating range of the GIITS using the new method the performance of GIITS and feature of target and background. This paper firstly makes analysis and summarization on the definite localizations of the traditional operating range equation of the GIITS. The localizations are mainly in two aspects. On one hand we should successively calculate two operating range values according to two requirements mentioned above and choose the minimum value as the analytic result. In the end the dispersion of the image and the effect of image dispersion are not considered in the traditional method an evaluation of operating range for fighter aircraft is accomplished as an example. The influence factors in every aspect on operating range were explored by the calculated result. The new operating range calculation model provides the theoretical basis for the design and applications as well as the comprehensive evaluation of a GIITS. 2011 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).