To estimate the motion parameters of a moving target before its passing by the closest point of approach （CPA） point in a low frequency analyzing and recording （LOFAR） field, an error-free theoretical method based...To estimate the motion parameters of a moving target before its passing by the closest point of approach （CPA） point in a low frequency analyzing and recording （LOFAR） field, an error-free theoretical method based on the joint measurement of target radiated noise＇s amplitude and frequency was presented. First, the error-free theoretical equations for target characteristic frequency, absolute velocity, the CPA, and amplitude of the radiation noise were derived by three equal interval measured values of the target amplitude and frequency. Then, the method to improve the calculation accuracy was given. Finally, the simulation and experiments were conducted in the air and showed the correctness of this method. By using one single piece of LOFAR, this method can calculate four target parameters and the relative error of each estimated parameter is less than 10%.展开更多
The present paper predicted the function of unknow genes by analyzing the co-expression data of Arabidopsis thaliana from biological pathway based on the shortest-path algorithm. This paper proposed that transitive co...The present paper predicted the function of unknow genes by analyzing the co-expression data of Arabidopsis thaliana from biological pathway based on the shortest-path algorithm. This paper proposed that transitive co-expression among genes can be used as an important attribute to link genes of the same biological pathway. The genes from the same biological pathway with similar functions are strongly correlated in expression. Moreover,the function of unknown genes can be predicted by the known genes where they are strongly correlated in expression lying on the same shortest-path from the biological pathway. Analyzing the Arabidopsis thaliana from the biological pathway,this study showed that this method can reliably reveal function of the unknown Arabidopsis thaliana genes and the approach of predicting gene function by transitiving co-expression in shortest-path is feasible and effective.展开更多
Pixel discontinuity in orthoimages occurs frequently due to altitude variations in the pitch and heading of an airplane, and low performance of real-time analyzing software. This study proposes a scheme to resolve pix...Pixel discontinuity in orthoimages occurs frequently due to altitude variations in the pitch and heading of an airplane, and low performance of real-time analyzing software. This study proposes a scheme to resolve pixel discontinuity. The proposed scheme includes the following steps: 1) capture images by a self-made hyperspectral imager;2) determine the pixel locations of orthoimages using a top-down approach;3) repair discontinuities by the Nearest Neighbor (NN) or Bilinear Interpolation (BL) approaches;and, 4) perform a dynamic range adjustment on the orthoimages, according to the maximum pixel value of the raw images and orthoimages. After applying the proposed scheme, this study found that pixel discontinuity was eliminated by both approaches, and that the software dependability and image quality were improved substantially. In addition, the computational efficiency of the NN approach was roughly two minutes faster than that of the BL due to its simpler computation. However, BL produces smoother image edges for landscapes.展开更多
基金Project supported by the National Natural Science Foundation of China （No. 51209173）
文摘To estimate the motion parameters of a moving target before its passing by the closest point of approach （CPA） point in a low frequency analyzing and recording （LOFAR） field, an error-free theoretical method based on the joint measurement of target radiated noise＇s amplitude and frequency was presented. First, the error-free theoretical equations for target characteristic frequency, absolute velocity, the CPA, and amplitude of the radiation noise were derived by three equal interval measured values of the target amplitude and frequency. Then, the method to improve the calculation accuracy was given. Finally, the simulation and experiments were conducted in the air and showed the correctness of this method. By using one single piece of LOFAR, this method can calculate four target parameters and the relative error of each estimated parameter is less than 10%.
基金Supported by Shanghai Municipal Education Committee Educationand Scientific Research (Grant No. 07ZZ60)~~
文摘The present paper predicted the function of unknow genes by analyzing the co-expression data of Arabidopsis thaliana from biological pathway based on the shortest-path algorithm. This paper proposed that transitive co-expression among genes can be used as an important attribute to link genes of the same biological pathway. The genes from the same biological pathway with similar functions are strongly correlated in expression. Moreover,the function of unknown genes can be predicted by the known genes where they are strongly correlated in expression lying on the same shortest-path from the biological pathway. Analyzing the Arabidopsis thaliana from the biological pathway,this study showed that this method can reliably reveal function of the unknown Arabidopsis thaliana genes and the approach of predicting gene function by transitiving co-expression in shortest-path is feasible and effective.
文摘Pixel discontinuity in orthoimages occurs frequently due to altitude variations in the pitch and heading of an airplane, and low performance of real-time analyzing software. This study proposes a scheme to resolve pixel discontinuity. The proposed scheme includes the following steps: 1) capture images by a self-made hyperspectral imager;2) determine the pixel locations of orthoimages using a top-down approach;3) repair discontinuities by the Nearest Neighbor (NN) or Bilinear Interpolation (BL) approaches;and, 4) perform a dynamic range adjustment on the orthoimages, according to the maximum pixel value of the raw images and orthoimages. After applying the proposed scheme, this study found that pixel discontinuity was eliminated by both approaches, and that the software dependability and image quality were improved substantially. In addition, the computational efficiency of the NN approach was roughly two minutes faster than that of the BL due to its simpler computation. However, BL produces smoother image edges for landscapes.
