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Imbalanced data set has caused a significant drawback of the classification performance attainable by most normal machine learning algorithm. However, the samples are often imbalanced. Therefore, how to reduce the effects of uneven distribution of training sets on text classification performance is a great challenge for machine learning on imbalanced data sets. Currently, the study on imbalaced data...
Image fusion technique has been widely applied to remote sensing image analysis and processing and the aim of the image fusion is to integrate the characteristic information of each image. By uniting the useful information a new image can be formed to improve the visual impression, and one can get a more accurate, comprehensive and reliable description for the same scene. In the traditional IHS transform...
A detection method of multipoint pulse signal based on ARM9 is presented in this paper. Pulse signals are detected which are on the three parts of wrist, "Cun" "Guan" "Chi", neck artery, and the fingertip. After isolated, amplified, and digitized, Pulse signal enters a DSP anti-interference filter, in which EMG and power frequency signal must be filtered out especially...
A rapid approach to shot boundary detection was introduced, which was based on the DC histogram Chi-square test and macroblock type statistics in one frame of MPEG-2 video sequence. Some information about DC histogram differences between I-frames was extracted first to detect in which GOP (group of picture) there are shot boundaries through the threshold active training method proposed in this paper...
The most efficient attack on symmetric-key systems is an exhaustive key search. A novel encryption method with infinite key space is presented by modify traditional book cipher. Infinite key space means the unbounded entropy of the key space, which can frustrate any exhaustive key search. Moreover, this book cipher is immune from frequency analysis. Experimental results show that both encryption and...
A risk situation evaluation model for network security is proposed based on analyzing security threat status. This method first perceived and identified the characteristics of critical risk factors, such as asset, vulnerability and threat, from multi-security-sensors. Then a quantitative evaluation algorithm was presented to estimate current threats and potential threats. By analyzing their threat...
Study of frequency coded synthetic aperture radar was concerned in this paper. A new frequency-domain extracted IFFT approach (FDE-IFFT) to obtain high range resolution profile was proposed, and the mathematical principle of this new method was detailed analyzed. Simulation results and series of radar images using time domain back-projection method were given in the end. All results proved that the...
Web topic is the theme indicated by Web pages. Some methods have been proposed to represent Web topic based on text mining. However, these methods canpsilat denote multimedia contents on Web page, such as images, audios, videos and so on. Consequently, text-based methods can't represent Web topic exactly because most Web pages consist of many multimedia contents. This paper proposes a new approach,...
The short term flicker severity Pst is an important index of power quality in the standards of IEC. Usually Discrete Fourier Transform (DFT) is used to calculate Pst, due to the inherent spectral leakage and barrier effect of DFT lead to low accuracy of Pst, therefore a method to improve the accuracy of Pst is proposed in this paper, the corn of this method is that, using DFT and Discrete Fourier...
The difference of the image generated by real target and digital-image-synthesiser (DIS) is analyzed. Then two methods are deduced to recognize deceivable jamming generated by DIS. One is the uncontinuity of the false target in Doppler section which is caused by the quantization of phase increment. The other is the target number and pose in the imaging field after ISAR processing when the pulse repetition...
According to the property of wavelet transform and fabric texture's Fourier spectrum, a new method for defect detection was presented. The proposed method is based on wavelet lifting transform with one resolution level. By using restoration scheme of the Fourier transform, the normal fabric textures of smooth sub-image in the spatial domain are removed by detecting the high-energy frequency components...
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