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氢火焰解吸离子化质谱技术快速分析印章印文 被引量:6
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作者 张强 詹绍旭 +4 位作者 王珊珊 黄小波 陈佳骏 时秋娜 郭寅龙 《质谱学报》 EI CAS CSCD 北大核心 2021年第4期470-479,I0007,共11页
建立了氢火焰解吸离子化质谱(HFDI-MS)法结合多元统计分析快速鉴别和溯源印章印文。采用金属探针取样,HFDI-MS技术快速分析光敏印油、原子印油和雕刻类印章专用印油(泥)所盖印形成的印文,得到的质谱信息差异显著。采用聚类分析进一步鉴... 建立了氢火焰解吸离子化质谱(HFDI-MS)法结合多元统计分析快速鉴别和溯源印章印文。采用金属探针取样,HFDI-MS技术快速分析光敏印油、原子印油和雕刻类印章专用印油(泥)所盖印形成的印文,得到的质谱信息差异显著。采用聚类分析进一步鉴别印章印文,结果表明,可将印章印文分为三类,并筛选出三类印章印文的26个特征离子信号。HFDI-MS技术操作简便、无需电压、分析快速直接,氢气的燃烧产物不会引入杂质干扰,不会对仪器造成污染,没有记忆效应,可为公安、司法、文物鉴定等领域印章印文的快速鉴别和溯源提供分析策略。 展开更多
关键词 氢火焰解吸离子化质谱(hfdi-MS) 印章印文 快速分析 鉴别 法庭科学
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Performance Analysis of Three Spectrum Sensing Detection Techniques with Ambient Backscatter Communication in Cognitive Radio Networks
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作者 Shayla Islam Anil Kumar Budati +2 位作者 Mohammad Kamrul Hasan Saoucene Mahfoudh Syed Bilal Hussian Shah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第10期813-825,共13页
In wireless communications, the Ambient Backscatter Communication (AmBC) technique is a promisingapproach, detecting user presence accurately at low power levels. At low power or a low Signal-to-Noise Ratio(SNR), ther... In wireless communications, the Ambient Backscatter Communication (AmBC) technique is a promisingapproach, detecting user presence accurately at low power levels. At low power or a low Signal-to-Noise Ratio(SNR), there is no dedicated power for the users. Instead, they can transmit information by reflecting the ambientRadio Frequency (RF) signals in the spectrum. Therefore, it is essential to detect user presence in the spectrum forthe transmission of data without loss or without collision at a specific time. In this paper, the authors proposed anovel Spectrum Sensing (SS) detection technique in the Cognitive Radio (CR) spectrum, by developing the AmBC.Novel Matched Filter Detection with Inverse covariance (MFDI), Cyclostationary Feature Detection with Inversecovariance (CFDI) and Hybrid Filter Detection with Inverse covariance (HFDI) approaches are used with AmBCto detect the presence of users at low power levels. The performance of the three detection techniques is measuredusing the parameters of Probability of Detection (PD), Probability of False Alarms (Pfa), Probability of MissedDetection (Pmd), sensing time and throughput at low power or low SNR. The results show that there is a significantimprovement via the HFDI technique for all the parameters. 展开更多
关键词 Ambient backscatter communication cognitive radio MFDI CFDI hfdi
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