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2FSK信号“指纹”特征的研究 被引量:18
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作者 王伦文 钟子发 《电讯技术》 北大核心 2003年第3期45-48,共4页
人有表示个体属性的指纹特征 ,无线电通信信号 (下称信号 )是否存在描述个体电台的电子“指纹”特征 (下称“指纹”特征 )呢 ?文中分析了信号“指纹”特征存在的可能性 ,并以 2FSK信号为例 ,论述了 2FSK信号应具有的“指纹”特征 ,同时... 人有表示个体属性的指纹特征 ,无线电通信信号 (下称信号 )是否存在描述个体电台的电子“指纹”特征 (下称“指纹”特征 )呢 ?文中分析了信号“指纹”特征存在的可能性 ,并以 2FSK信号为例 ,论述了 2FSK信号应具有的“指纹”特征 ,同时提取了其中部分“指纹”特征。 展开更多
关键词 2FSK信号 “指纹”特征 信号处理 无线电通信信号
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基于移动通信中的无线信道“指纹”特征模型研究 被引量:3
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作者 李琰 《信息通信》 2015年第11期23-24,共2页
移动通信中无线信道的传输环境比较复杂,研究无线信道的特征最直观的方式就是测量无线信道特征参数,而无线信道测量的主要参数就是路径传播时延,研究信道传输特性有助于无线通信行业的发展。文章对实际的无线信道"指纹"特征... 移动通信中无线信道的传输环境比较复杂,研究无线信道的特征最直观的方式就是测量无线信道特征参数,而无线信道测量的主要参数就是路径传播时延,研究信道传输特性有助于无线通信行业的发展。文章对实际的无线信道"指纹"特征建立抽头延迟线性模型,并通过了MATLAB仿真实现,旨在从"指纹"特征统计的角度上有效地区分出无线信道的场景或区域。 展开更多
关键词 移动通信 无线信道 “指纹”特征 仿真
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X-ray Comparative Analysis of Rhubarb in Different Production Areas of Qinghai 被引量:1
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作者 王宁芳 拉本 《Agricultural Science & Technology》 CAS 2009年第6期119-120,124,共3页
[Objective] The aim of this study was to provide a basis for distinguishing quality of rhubarb in different production areas. [Method ] X-ray diffraction patterns of rhubarbs in different production areas of Qinghai w... [Objective] The aim of this study was to provide a basis for distinguishing quality of rhubarb in different production areas. [Method ] X-ray diffraction patterns of rhubarbs in different production areas of Qinghai were obtained by X-ray diffraction analysis, and then its similarity analysis was also investigated. [ Result] The content of chemical components in rhubarbs from different production areas had differences, but its diffraction patterns and diffraction peaks had certain fingerprint characteristics. [ Conclusion] X-ray diffraction method is a fast and effective method for identifying rhubarb and other Chinese herbal medicines in different production areas. 展开更多
关键词 RHUBARB X-RAY Diffraction map Diffraction peak Fingerprint characteristics
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Fingerprint Liveness Detection Based on Multi-Scale LPQ and PCA 被引量:13
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作者 Chengsheng Yuan Xingming Sun Rui Lv 《China Communications》 SCIE CSCD 2016年第7期60-65,共6页
Fingerprint authentication system is used to verify users' identification according to the characteristics of their fingerprints.However,this system has some security and privacy problems.For example,some artifici... Fingerprint authentication system is used to verify users' identification according to the characteristics of their fingerprints.However,this system has some security and privacy problems.For example,some artificial fingerprints can trick the fingerprint authentication system and access information using real users' identification.Therefore,a fingerprint liveness detection algorithm needs to be designed to prevent illegal users from accessing privacy information.In this paper,a new software-based liveness detection approach using multi-scale local phase quantity(LPQ) and principal component analysis(PCA) is proposed.The feature vectors of a fingerprint are constructed through multi-scale LPQ.PCA technology is also introduced to reduce the dimensionality of the feature vectors and gain more effective features.Finally,a training model is gained using support vector machine classifier,and the liveness of a fingerprint is detected on the basis of the training model.Experimental results demonstrate that our proposed method can detect the liveness of users' fingerprints and achieve high recognition accuracy.This study also confirms that multi-resolution analysis is a useful method for texture feature extraction during fingerprint liveness detection. 展开更多
关键词 fingerprint liveness detection wavelet transform local phase quantity principal component analysis support vector machine
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Chemical fingerprinting of Su-He-Xiang-Wan and attribution of major characteristic peaks for its quality control by GC-MS 被引量:1
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作者 WANG Wei-ping LIN Juan +2 位作者 ZHANG Liang-xiao ZHANG Ming-yue LIANG Yi-zeng 《Journal of Central South University》 SCIE EI CAS 2013年第8期2115-2123,共9页
A simple and facile gas chromatography-mass spectrometer (GC-MS) fingerprint of Su-He-Xiang-Wan (SHXW) was developed, the similarity analysis was conducted, and attribution of the major characteristic peaks was id... A simple and facile gas chromatography-mass spectrometer (GC-MS) fingerprint of Su-He-Xiang-Wan (SHXW) was developed, the similarity analysis was conducted, and attribution of the major characteristic peaks was identified for SHXW quality control. GC-MS analysis was performed on a QP2010 instrument (Shimadzu, Japan) equipped with a capillary column of RTX-5MS. The column temperature was initiated at 50℃, held for 5 min, increased at the rate of 3 ℃/min to 120 ℃, held for 2 min, and then increased at the rate of 4 ℃/min to 220℃, held for 10 min. Helium carrier gas was used at a constant flow rate of 1.3 mL/min. Mass conditions were ionization voltage, 70 eV; injector temperature, 250℃; ion source temperature, 250 ℃; splitting ratio, 30:1; full scan mode in the 40-500 Da mass ranges with rate of 0.2 s per scan. Attribution of the major characteristic peaks was identified for SHXW by comparing the chemical standards, references of Chinese herbal medicines and the negative controls of prescription samples (NC) of SHXW. With the help of the temperature-programmed retention indices (PTRIs) used together with mass spectra and chemical standards, 25 major characteristic peaks have been identified. Nine volatile medicinal materials were identified in the prescription of SHXW by attributing to the 27 major characteristic peaks. The results demonstrate that the proposed method is a powerful approach to quality control of complex herbal medicines. 展开更多
关键词 chromatographic fingerprint attribution analysis quality control herbal medicines complex prescription
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Quality evaluation of Polyporus umbellatus based on HPLC specific chromatogram and fingerprint analysis 被引量:2
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作者 Weijuan Jia Shizhong Chen +4 位作者 Jianhua Sun Zongli Bai Yazhuo Huang Yuankuan Zhang Hong Wang 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2020年第12期896-907,共12页
To evaluate the quality of Polyporus umbellatus,we established a simple,repeatable and reliable method based on high performance liquid chromatography(HPLC)for specific chromatogram and fingerprint analysis,which was ... To evaluate the quality of Polyporus umbellatus,we established a simple,repeatable and reliable method based on high performance liquid chromatography(HPLC)for specific chromatogram and fingerprint analysis,which was applied to analyze samples of medicinal materials and decoction pieces collected from different regions.Finally,ten characteristic peaks were designated in the specific chromatograms and applied to the authenticate identification of P.umbellatus samples.Nine common peaks were designated in the fingerprints,and then the similarities between 32 batches of samples were calculated.Among them,eight compounds were identified by HPLC-APCI-IT-TOF-MS^(n),four of which were identified in specific chromatograms and four in fingerprints.In the present study,we,for the first time,combined HPLC specific chromatograms and fingerprints for the species identification and quality evaluation of P.umbellatus.Collectively,our findings provided a new method for establishing a comprehensive quality standard of P.umbellatus. 展开更多
关键词 Polyporus umbellatus HPLC Specific chromatogram FINGERPRINT APCI-IT-TOF-MS^(n) Quality evaluation
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Frequency-hopping transmitter fingerprint feature recognition with kernel projection and joint representation
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作者 Ping SUI Ying GUO +1 位作者 Kun-feng ZHANG Hong-guang LI 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2019年第8期1133-1147,共15页
Frequency-hopping(FH)is one of the commonly used spread spectrum techniques that finds wide applications in communications and radar systems because of its inherent capability of low interception,good confidentiality,... Frequency-hopping(FH)is one of the commonly used spread spectrum techniques that finds wide applications in communications and radar systems because of its inherent capability of low interception,good confidentiality,and strong antiinterference.However,non-cooperation FH transmitter classification is a significant and challenging issue for FH transmitter fingerprint feature recognition,since it not only is sensitive to noise but also has non-linear,non-Gaussian,and non-stability characteristics,which make it difficult to guarantee the classification in the original signal space.Some existing classifiers,such as the sparse representation classifier(SRC),generally use an individual representation rather than all the samples to classify the test data,which over-emphasizes sparsity but ignores the collaborative relationship among the given set of samples.To address these problems,we propose a novel classifier,called the kernel joint representation classifier(KJRC),for FH transmitter fingerprint feature recognition,by integrating kernel projection,collaborative feature representation,and classifier learning into a joint framework.Extensive experiments on real-world FH signals demonstrate the effectiveness of the proposed method in comparison with several state-of-the-art recognition methods. 展开更多
关键词 Frequency-hopping Fingerprint feature Kernel function Joint representation Transmitter recognition
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