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Variance-based fingerprint distance adjustment algorithm for indoor localization 被引量:7
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作者 Xiaolong Xu Yu Tang +1 位作者 Xinheng Wang Yun Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第6期1191-1201,共11页
The multipath effect and movements of people in indoor environments lead to inaccurate localization. Through the test, calculation and analysis on the received signal strength indication (RSSI) and the variance of R... The multipath effect and movements of people in indoor environments lead to inaccurate localization. Through the test, calculation and analysis on the received signal strength indication (RSSI) and the variance of RSSI, we propose a novel variance-based fingerprint distance adjustment algorithm (VFDA). Based on the rule that variance decreases with the increase of RSSI mean, VFDA calculates RSSI variance with the mean value of received RSSIs. Then, we can get the correction weight. VFDA adjusts the fingerprint distances with the correction weight based on the variance of RSSI, which is used to correct the fingerprint distance. Besides, a threshold value is applied to VFDA to improve its performance further. VFDA and VFDA with the threshold value are applied in two kinds of real typical indoor environments deployed with several Wi-Fi access points. One is a quadrate lab room, and the other is a long and narrow corridor of a building. Experimental results and performance analysis show that in indoor environments, both VFDA and VFDA with the threshold have better positioning accuracy and environmental adaptability than the current typical positioning methods based on the k-nearest neighbor algorithm and the weighted k-nearest neighbor algorithm with similar computational costs. 展开更多
关键词 indoor localization fingerprint localization receivedsignal strength indication (RSSI) variance fingerprint distance.
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Fingerprint singular points extraction based on orientation tensor field and Laurent series 被引量:3
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作者 刘琴 彭可 +4 位作者 刘巍 谢琴 李仲阳 兰浩 金耀 《Journal of Central South University》 SCIE EI CAS 2014年第5期1927-1934,共8页
Singular point(SP)extraction is a key component in automatic fingerprint identification system(AFIS).A new method was proposed for fingerprint singular points extraction,based on orientation tensor field and Laurent s... Singular point(SP)extraction is a key component in automatic fingerprint identification system(AFIS).A new method was proposed for fingerprint singular points extraction,based on orientation tensor field and Laurent series.First,fingerprint orientation flow field was obtained,using the gradient of fingerprint image.With these gradients,fingerprint orientation tensor field was calculated.Then,candidate SPs were detected by the cross-correlation energy in multi-scale Gaussian space.The energy was calculated between fingerprint orientation tensor field and Laurent polynomial model.As a global descriptor,the Laurent polynomial coefficients were allowed for rotational invariance.Furthermore,a support vector machine(SVM)classifier was trained to remove spurious SPs,using cross-correlation coefficient as a feature vector.Finally,experiments were performed on Singular Point Detection Competition 2010(SPD2010)database.Compared to the winner algorithm of SPD2010 which has best accuracy of 31.90%,the accuracy of proposed algorithm is 45.34%.The results show that the proposed method outperforms the state-of-the-art detection algorithms by large margin,and the detection is invariant to rotational transformations. 展开更多
关键词 fingerprint extraction singular point fingerprint orientation tensor field Laurent series rotational invariance supportvector machine (SVM)
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Digital signature systems based on smart card and fingerprint feature 被引量:3
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作者 You Lin Xu Maozhi Zheng Zhiming 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2007年第4期825-834,共10页
Two signature systems based on smart cards and fingerprint features are proposed. In one signature system, the cryptographic key is stored in the smart card and is only accessible when the signer's extracted fingerpr... Two signature systems based on smart cards and fingerprint features are proposed. In one signature system, the cryptographic key is stored in the smart card and is only accessible when the signer's extracted fingerprint features match his stored template. To resist being tampered on public channel, the user's message and the signed message are encrypted by the signer's public key and the user's public key, respectively. In the other signature system, the keys are generated by combining the signer's fingerprint features, check bits, and a rememberable key, and there are no matching process and keys stored on the smart card. Additionally, there is generally more than one public key in this system, that is, there exist some pseudo public keys except a real one. 展开更多
关键词 digital signature fingerprint feature error-correcting code cryptographic key smart card
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A new reaction system to determine nonlinear chemical fingerprint and its use in Panax ginseng identification method based on double reaction system 被引量:5
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作者 TAN Xue-ying DENG Fei-yue +2 位作者 ZHANG Tai-ming HUANG Jian CHEN Chun-nan 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第8期1895-1903,共9页
A new reaction system to determine nonlinear chemical fingerprint(NCF)and its use in identification method based on double reaction system was researched.Panax ginsengs,such as ginseng,American ginseng and notoginseng... A new reaction system to determine nonlinear chemical fingerprint(NCF)and its use in identification method based on double reaction system was researched.Panax ginsengs,such as ginseng,American ginseng and notoginseng were identified by the method.The NCFs of the three samples of Panax ginsengs were determined through two nonlinear chemical systems,namely system 1 consisting of sample components,H2SO4,MnSO4,NaBrO3,acetone and the new system,system 2 consisting of sample components,H2SO4,(NH4)4Ce(SO4)2,NaBrO3 and citric acid.The comparison between the results determined through systems 1 and 2 shows that the speed to determine NCF through system 2 is much faster than that through system 1;for systems 1 and 2,the system similarities of the same kind of samples are≥98.09%and 99.78%,respectively,while those of different kinds of samples are≤63.04%and 86.34%,respectively.The results to identify the kinds of some samples by system similarity pattern show that both the accuracies of identification methods based on single system 1 and 2 are≥95.6%,and the average values are 97.1%and 96.3%,respectively;the accuracy of the method based on double system is≥97.8%,and the average accuracy is 99.3%.The accuracy of the method based on double system is higher than that based on any single system. 展开更多
关键词 nonlinear chemical fingerprint double reaction system single reaction system authenticity identification Panax ginsengs
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Quantitative similarity assessment of non-linear chemical fingerprint of traditional Chinese medicine by similarity system theory 被引量:5
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作者 周菊峰 方宣启 +4 位作者 张泰铭 赵哲 朱蓉 向凤琴 乔君喜 《Journal of Central South University》 SCIE EI CAS 2011年第2期343-352,共10页
The similarities of the non-linear chemical (NLC) fingerprints of Radix Glycyrrhizaes from four producing areas and eight other traditional Chinese medicines (TCMs) were calculated, using a systemic similarity cal... The similarities of the non-linear chemical (NLC) fingerprints of Radix Glycyrrhizaes from four producing areas and eight other traditional Chinese medicines (TCMs) were calculated, using a systemic similarity calculation method proposed and three other main calculation ones (Euclidean distance, correlation coefficient and included angle cosine). All of the correlation coefficient similarities of different TCMs are higher than 0.952, and the included angle cosines are all higher than 0.962. So, both the conelation coefficient and included angle cosine similarities are unable to be used as the criteria for quantitatively evaluating the similarities of NLC fingerprints of TCMs. Although all of the Euclidean distance similarities of Berry Liquorices from four producing areas are less than 73, those of the other eight TCMs are all more than 180. The Euclidean distance cannot reflect the relative magnitudes of the feature differences in the NLC fingerprints very correctly. The systemic similarity method is the best among the four ones. All of the systemic similarities of Berry Liquorices from the four producing areas are higher than 0.962, while those of the other eight TCMs are all lower than 0.805, and the systemic similarity can reflect the differences between samples most faithfully, and can be used as a quantitative one evaluating the similarities of NLC fingerprints of TCMs, by which TCM could be distinguished and evaluated quickly, simply and exactly. 展开更多
关键词 nonlinear chemistry fingerprint systemic similarity traditional Chinese medicine
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Chromatographic fingerprint analysis of Fructus Aurantii Immaturus by HPLC-DAD and chemometric methods 被引量:4
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作者 徐小娜 蒋军辉 +3 位作者 梁逸曾 李晓如 易伦朝 成金乐 《Journal of Central South University》 SCIE EI CAS 2011年第2期353-360,共8页
An efficient method for quality control of Fructus Aurantii Immaturus (FAI),a famous traditional Chinese medicine (TCM) was established. A simple and reliable high-performance liquid chromatography-photodiode array de... An efficient method for quality control of Fructus Aurantii Immaturus (FAI),a famous traditional Chinese medicine (TCM) was established. A simple and reliable high-performance liquid chromatography-photodiode array detector (HPLC-DAD) procedure coupled with chemometric methods was developed for fingerprint analysis,qualitative analysis and quantitative determination of this herb. In qualitative and quantitative analyses,heuristic evolving latent projection (HELP) method was employed to resolve the overlapping peaks of the tested samples. Two bioactive components,namely hesperidin and naringin,are confirmed and determined,together with four flavonoids compounds tentatively identified including two new ones. From fingerprint analysis,the fingerprint data were processed with correlation coefficients for quantitative expression of their similarity and dissimilarity. The developed method based on an integration of chromatographic fingerprint and quantitative analysis is scientific,and the obtained results can be applied to the quality control of herb medicine. 展开更多
关键词 fingerprint quality control Fructus Aurantii Immaturus high-performance liquid chromatography heuristic evolvinglatent projection method HESPERIDIN NARINGIN
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Multi-line code: A low complexity revocable fingerprint template for cancelable biometrics 被引量:1
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作者 WONG Wei-jing WONG Mou-ling Dennis KHO Yau-hee 《Journal of Central South University》 SCIE EI CAS 2013年第5期1292-1297,共6页
A low computational cost cancelable fingerprint template, namely the multi-line codes was proposed. The formulation of a single-line code involves the inspection of minutiae distribution along a straight line construc... A low computational cost cancelable fingerprint template, namely the multi-line codes was proposed. The formulation of a single-line code involves the inspection of minutiae distribution along a straight line constructed based on the reference minutia. Multi-line code is introduced to elevate the performance by combining several single-line codes. Experiments were carried out on a few FVC databases. It has been proven that the proposed method yields relatively low computational complexity as compared to existing minutiae distribution-based methods, while preserving the performance. The equal error rate obtained for FVC2002 DB1 is 4.69% in stolen-key case, and the total arithmetic operations utilized are 14 520 additions and zero multiplication. 展开更多
关键词 cancelable fingerprint template multi-line code single-line code stolen-key case
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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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Fingerprinting Analysis of the Introgressed lines from Gossypium hirsutum L.× G.barbadense L.based on AFLP markers
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作者 LIU Zhao-hui1,ZHANG Yong2,DONG Shun-wen1,WANG Jun1(1.Industrial Crop Breeding and Cultivation Institute,Sichuan Academy of Agriculture Sciences,Jianyang,Sichuan 641400,China 2.School of Life Science and Technology,University of Electronic Science and Technology of China,Chengdu,Sichuan 610054,China) 《棉花学报》 CSCD 北大核心 2008年第S1期79-,共1页
The main cultivated varieties in the world belong to the species of upland cotton(Gossypium hirsutum L.),and their genetic background is very narrow.However,the wild species and races in
关键词 introgressed line TETRAPLOID molecular phylogeny fingerprinting AFLP
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金银花中多组分同步检测与质量综合评价方法的研究 被引量:1
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作者 赵云平 赵琳琳 +4 位作者 魏静娜 焦艺博 苏蘩 孙萌 刘征辉 《辽宁中医杂志》 北大核心 2025年第2期132-135,I0001,共5页
目的研究建立金银花中多组分的同步检测与质量综合评价的方法。方法通过超高效液相色谱法,采用Waters ACQUITY BEH C 18(100 mm×2.1 mm,1.7μm)色谱柱,流动相为乙腈-0.1%磷酸水溶液,洗脱方式为梯度洗脱,流速为0.2 mL/min,柱温35℃... 目的研究建立金银花中多组分的同步检测与质量综合评价的方法。方法通过超高效液相色谱法,采用Waters ACQUITY BEH C 18(100 mm×2.1 mm,1.7μm)色谱柱,流动相为乙腈-0.1%磷酸水溶液,洗脱方式为梯度洗脱,流速为0.2 mL/min,柱温35℃。结果建立了超高效液相色谱法同时测定金银花中8种组分含量的方法,并结合指纹图谱和聚类分析对金银花的质量进行综合评价。结论建立的超高效液相色谱分析方法简便快速,节省了检测时间,提高了检测效率;指纹图谱分析结果证明了蓟州和津南种植的金银花所含组分比较一致,相似度高,组分含量通过聚类分析加以区分。 展开更多
关键词 金银花 多组分 指纹图谱 聚类分析 质量评价
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基于高通量测序的青花菜KASP标记开发与应用 被引量:1
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作者 张振超 陶美奇 +4 位作者 潘永飞 孙国胜 王传友 安林海 戴忠良 《核农学报》 北大核心 2025年第3期513-521,I0003-I0005,共12页
为提高青花菜分子标记辅助育种水平,本研究基于高通量测序数据开发了70组KASP标记,并采用KASP检测平台对43份青花菜试验材料进行分型,根据分型结果筛选出分型效果好、多态性高的标记,用于指纹图谱构建、遗传关系确定和纯度鉴定。结果表... 为提高青花菜分子标记辅助育种水平,本研究基于高通量测序数据开发了70组KASP标记,并采用KASP检测平台对43份青花菜试验材料进行分型,根据分型结果筛选出分型效果好、多态性高的标记,用于指纹图谱构建、遗传关系确定和纯度鉴定。结果表明,70组KASP标记中,未分型成功有3个,未分型材料>5份有13个,多态性差的有6个,分型成功48个(成功率68.6%)。48个标记中,多态性信息含量(PIC)值≥0.30的标记有37个(占比77.08%),其中PIC值为0.37的标记数量最多,为11个,0.38的标记有3个。将48个标记的分型结果转化为二元编码数据,获得了43份青花菜育种材料的SNP-DNA指纹图谱。聚类分析结果发现,Br05与其他材料的遗传关系较远;Br12和Br19、Br33和Br34之间遗传系数均为100,Br14和Br32的遗传系数为99,表明两两间为同一株系的可能性大,这与在田间的表型观察结果基本一致。10组标记对30株Br19的一致性进行鉴定,发现纯度值区间为83.3%~96.7%,说明Br19株系间存在差异;采用10组标记对亲本Br19、Br35和杂交种F1(Br19×Br35)进行基因分型,结果有5个标记(SNP07、SNP09、SNP10、SNP11和SNP19)在三者间的分型结果不同,可用于杂交制种田F1(Br19×Br35)种子纯度鉴定。本研究结果对青花菜种质资源鉴定、分子标记辅助育种与新品种保护具有重要的应用价值。 展开更多
关键词 高通量测序 竞争性等位基因特异性PCR 指纹图谱 纯度鉴定 分子标记
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芪葛颗粒干法制粒工艺优化及其物理指纹图谱建立 被引量:1
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作者 李航 周恩丽 +3 位作者 汪盛华 张欣 肖伟 王振中 《中成药》 北大核心 2025年第2期401-407,共7页
目的优化芪葛颗粒干法制粒工艺,并建立其物理指纹图谱。方法正交试验优化干燥工艺,单因素试验优化填充剂、矫味剂。以送料速度、轧轮转速、轧轮压力为影响因素,一次成型率、吸湿率、溶化率、休止角的综合评分为评价指标,Box-Behnken响... 目的优化芪葛颗粒干法制粒工艺,并建立其物理指纹图谱。方法正交试验优化干燥工艺,单因素试验优化填充剂、矫味剂。以送料速度、轧轮转速、轧轮压力为影响因素,一次成型率、吸湿率、溶化率、休止角的综合评分为评价指标,Box-Behnken响应面法优化干法制粒工艺。结果最佳干燥工艺为一区、二区、三区加热温度130、125、120℃,履带传送频率10 Hz,浸膏相对密度1.2;最佳填充剂为糊精;最佳矫味剂为0.5%甜菊糖苷和0.5%甜橙香精;最佳干法制粒工艺为送料速度28 Hz,轧轮速度17 Hz,轧轮压力7 MPa,综合评分为0.7465。15批样品物理指纹图谱相似度均大于0.98。结论该工艺稳定可行,可为芪葛颗粒的工业化生产提供参考。 展开更多
关键词 芪葛颗粒 干法制粒工艺 物理指纹图谱 Box-Behnken响应面法
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虚拟AP融合CNN模型的自适应RSSI指纹定位方法 被引量:1
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作者 吴仕勋 黄文鲜 +1 位作者 李敏 徐凯 《计算机应用与软件》 北大核心 2025年第1期72-81,共10页
基于RSSI(Received Signal Strength Indication)位置指纹的Wi-Fi室内定位现已被大量应用于各类基于位置信息的服务中。但指纹定位的精度受到RSSI信号的剧烈波动影响,难以满足高精度位置信息服务的需求。为克服该困难,提出一种结合虚拟A... 基于RSSI(Received Signal Strength Indication)位置指纹的Wi-Fi室内定位现已被大量应用于各类基于位置信息的服务中。但指纹定位的精度受到RSSI信号的剧烈波动影响,难以满足高精度位置信息服务的需求。为克服该困难,提出一种结合虚拟AP技术与高精度CNN(Convolutional Neural Network)判别模型的定位方法。该方法通过距离比定位得到虚拟AP的位置,并将该信息与RSSI融合作为数据增强CNN模型的输入,确定样本的位置。设计实验方案采集实际的用户终端RSSI数据,构建指纹定位的数据集,验证所提出的指纹定位方案的有效性。实验结果表明,在该数据集上,所提出的方法在确定区域时的准确度达到91%,并将95%的定位误差控制在2 m以内。对比现有的定位方案,所提出的方案在定位精度上有显著提升。 展开更多
关键词 接收信号强度指示 指纹定位 卷积神经网络 虚拟AP
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栀子柏皮汤复方中药高效液相色谱指纹图谱的建立 被引量:1
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作者 李燕 滕乐 +3 位作者 唐军相 张德庆 李阳 韩忠耀 《理化检验(化学分册)》 北大核心 2025年第6期697-702,共6页
按照《伤寒论》收载的方法制备10批栀子柏皮汤供试品溶液,在Diamonsil C18色谱柱上进行分离,在柱温35℃条件下以不同体积比的0.2%(体积分数)甲酸溶液-甲醇混合溶液为流动相进行梯度洗脱,在波长250 nm处检测,记录色谱图。根据中药色谱指... 按照《伤寒论》收载的方法制备10批栀子柏皮汤供试品溶液,在Diamonsil C18色谱柱上进行分离,在柱温35℃条件下以不同体积比的0.2%(体积分数)甲酸溶液-甲醇混合溶液为流动相进行梯度洗脱,在波长250 nm处检测,记录色谱图。根据中药色谱指纹图谱相似度评价系统(2012版)建立了栀子柏皮汤复方中药的高效液相色谱(HPLC)指纹图谱。结果显示:10批栀子柏皮汤指纹图谱中有15个共有峰,其中3个共有峰归属于黄柏,其余共有峰均归属于栀子。与对照品比对,确认9、10、13号峰分别为京尼平龙胆双糖苷、栀子苷、盐酸小檗碱。10批栀子柏皮汤指纹图谱与对照指纹图谱的相似度为0.880~0.949。 展开更多
关键词 栀子柏皮汤 高效液相色谱法 指纹图谱
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宣肺败毒方高效液相色谱指纹图谱的建立 被引量:1
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作者 韩忠耀 张德庆 +4 位作者 魏啸宇 谢星腾 赵昌涵 唐文双 杨政敏 《理化检验(化学分册)》 北大核心 2025年第4期443-447,共5页
按照处方量制备宣肺败毒方,武火煮沸后,文火煎煮60 min,纱布过滤,文火浓缩煎煮至400 m L,滤纸过滤,再用0.45μm水系滤膜过滤,在Agela Promosil C_(18)色谱柱上进行分离,在柱温30℃条件下以不同体积比的0.1%(体积分数)磷酸溶液-甲醇混合... 按照处方量制备宣肺败毒方,武火煮沸后,文火煎煮60 min,纱布过滤,文火浓缩煎煮至400 m L,滤纸过滤,再用0.45μm水系滤膜过滤,在Agela Promosil C_(18)色谱柱上进行分离,在柱温30℃条件下以不同体积比的0.1%(体积分数)磷酸溶液-甲醇混合溶液为流动相进行梯度洗脱,在波长220 nm处检测,记录色谱图。根据中药色谱指纹图谱相似度评价系统(2004 A版)建立了宣肺败毒方的高效液相色谱(HPLC)指纹图谱。结果显示,11批宣肺败毒方指纹图谱中有24个共有峰,与大黄素对照品比对,确认24号峰对应大黄素,11批宣肺败毒方指纹图谱与对照指纹图谱的相似度为0.988~1.000。 展开更多
关键词 宣肺败毒方 高效液相色谱法 指纹图谱
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基于Bert+GCN多模态数据融合的药物分子属性预测 被引量:1
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作者 闫效莺 靳艳春 +1 位作者 冯月华 张绍武 《生物化学与生物物理进展》 北大核心 2025年第3期783-794,共12页
目的药物研发成本高、周期长且成功率低。准确预测分子属性对有效筛选药物候选物、优化分子结构具有重要意义。基于特征工程的传统分子属性预测方法需研究人员具备深厚的学科背景和广泛的专业知识。随着人工智能技术的不断成熟,涌现出... 目的药物研发成本高、周期长且成功率低。准确预测分子属性对有效筛选药物候选物、优化分子结构具有重要意义。基于特征工程的传统分子属性预测方法需研究人员具备深厚的学科背景和广泛的专业知识。随着人工智能技术的不断成熟,涌现出大量优于传统特征工程方法的分子属性预测算法。然而这些算法模型仍然存在标记数据稀缺、泛化性能差等问题。鉴于此,本文提出一种基于Bert+GCN的多模态数据融合的分子属性预测算法(命名为BGMF),旨在整合药物分子的多模态数据,并充分利用大量无标记药物分子训练模型学习药物分子的有用信息。方法本文提出了BGMF算法,该算法根据药物SMILES表达式分别提取了原子序列、分子指纹序列和分子图数据,采用预训练模型Bert和图卷积神经网络GCN结合的方式进行特征学习,在挖掘药物分子中“单词”全局特征的同时,融合了分子图的局部拓扑特征,从而更充分利用分子全局-局部上下文语义关系,之后,通过对原子序列和分子指纹序列的双解码器设计加强分子特征表达。结果5个数据集共43个分子属性预测任务上,BGMF方法的AUC值均优于现有其他方法。此外,本文还构建独立测试数据集验证了模型具有良好的泛化性能。对生成的分子指纹表征(molecular fingerprint representation)进行t-SNE可视化分析,证明了BGMF模型可成功捕获不同分子指纹的内在结构与特征。结论通过图卷积神经网络与Bert模型相结合,BGMF将分子图数据整合到分子指纹恢复和掩蔽原子恢复的任务中,可以有效地捕捉分子指纹的内在结构和特征,进而高效预测药物分子属性。 展开更多
关键词 Bert预训练 注意力机制 分子指纹 分子属性预测 图卷积神经网络
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DTWAWKNN驱动的蓝牙/WiFi指纹定位方法 被引量:1
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作者 杨明 纪冬华 《导航定位学报》 北大核心 2025年第3期189-197,共9页
针对蓝牙/无线保真(WiFi)指纹定位效果差、算法复杂度高等问题,提出一种动态时间规整辅助加权K近邻(DTWAWKNN)驱动的蓝牙/WiFi指纹定位方法:离线阶段,通过动态时间规整(DTW)算法计算不等维度的蓝牙、WiFi和蓝牙/WiFi混合指纹之间的相似... 针对蓝牙/无线保真(WiFi)指纹定位效果差、算法复杂度高等问题,提出一种动态时间规整辅助加权K近邻(DTWAWKNN)驱动的蓝牙/WiFi指纹定位方法:离线阶段,通过动态时间规整(DTW)算法计算不等维度的蓝牙、WiFi和蓝牙/WiFi混合指纹之间的相似度,并基于加权K近邻(WKNN)实现匹配定位,然后以蓝牙、WiFi及蓝牙/WiFi混合指纹库与蓝牙、WiFi及蓝牙/WiFi混合指纹的匹配结果为定位特征,构建基于多类型指纹匹配定位结果的离线定位指纹库;在线阶段,基于DTWAWKNN实现蓝牙、WiFi和蓝牙/WiFi混合指纹之间的匹配定位,获取基于多类型指纹匹配定位结果的在线定位指纹,再基于WKNN算法实现离线定位指纹库和在线定位指纹的匹配定位。实验结果表明,提出方法的定位效果远优于WKNN、随机森林(RF)和支持向量机(SVM),定位精度可至少提高67.74%,定位稳定性最少提高54.51%,算法复杂度至少降低77.9%。 展开更多
关键词 蓝牙 无线保真(WiFi) 指纹定位 动态时间规整(DTW) 加权K近邻(WKNN)
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基于SSR标记“藏乌梨”品种真实性鉴定
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作者 张靖国 陈启亮 +3 位作者 杨晓平 范净 杜威 胡红菊 《中国南方果树》 北大核心 2025年第4期198-200,共3页
近期梨果市场有种黑色果皮、号称产自西藏的“藏乌梨”受到热捧,但其品种真实性不详。本研究以市售“藏乌梨”为试材,通过基于SSR标记的分子指纹图谱构建及与国家砂梨种质资源圃(武汉)数据库进行比对,并结合果实形态学特征分析表明,所... 近期梨果市场有种黑色果皮、号称产自西藏的“藏乌梨”受到热捧,但其品种真实性不详。本研究以市售“藏乌梨”为试材,通过基于SSR标记的分子指纹图谱构建及与国家砂梨种质资源圃(武汉)数据库进行比对,并结合果实形态学特征分析表明,所谓“藏乌梨”是“玉露香”,而非西藏的“乌梨”;其黑皮疑似由于在果实成熟采收后经某种热处理而成。 展开更多
关键词 藏乌梨 SSR 指纹图谱 玉露香梨
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淫羊藿及其炮制品化学组成及对MC3T3-E1细胞的增殖和成骨作用研究
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作者 成光宇 李盼 +6 位作者 宋来辉 梁金玲 曹文轩 于澎 戴雨霖 刘佳 许天阳 《中华中医药学刊》 北大核心 2025年第8期178-184,I0050,I0051,共9页
目的分析淫羊藿(Epimedii folium)及其炮制品化学组成,并探究其提取物对小鼠胚胎成骨细胞前体细胞(Mouse embryonic preosteoblast cells,MC3T3-E1 cells)的增殖及成骨作用。方法取10批淫羊藿,分别加工炮制成羊脂油炙淫羊藿和盐炙淫羊藿... 目的分析淫羊藿(Epimedii folium)及其炮制品化学组成,并探究其提取物对小鼠胚胎成骨细胞前体细胞(Mouse embryonic preosteoblast cells,MC3T3-E1 cells)的增殖及成骨作用。方法取10批淫羊藿,分别加工炮制成羊脂油炙淫羊藿和盐炙淫羊藿各10批,利用高效液相色谱法(High performance liquid chromatography,HPLC)测定样品中黄酮类成分含量,并结合液相色谱指纹图谱及多元统计分析方法,探究淫羊藿中黄酮类化合物在炮制前后变化规律;建立地塞米松(Dexamethasone,DEX)诱导的MC3T3-E1细胞的成骨抑制模型,通过测定细胞中碱性磷酸酶(Alkaline phosphatase,ALP)、骨保护素(Osteoprotegerin,OPG)和骨钙素(Osteocalcin,OCN)的表达量来评价淫羊藿及其炮制品的抗骨质疏松效果,进一步探讨淫羊藿及其炮制品抗骨质疏松作用不同可能存在的原因。结果建立淫羊藿及其炮制品HPLC指纹图谱,并对指纹图谱进行相似度评价,识别出共有峰16个;聚类分析结果将朝藿定A、朝藿定B和朝藿定C归为一类,淫羊藿苷和宝藿苷I归为一类;各黄酮含量的极坐标气泡图显示初级黄酮苷(朝藿定A、朝藿定B和朝藿定C)含量在炮制后整体减少,次级黄酮苷(淫羊藿苷和宝藿苷I)含量在炮制后整体增加;抗骨质疏松活性数据表明,淫羊藿不同炮制品均具有一定的成骨增殖作用,其中淫羊藿盐炙品对DEX抑制的成骨细胞活性增强作用最为明显。结论采用指纹图谱相似度分析和聚类分析对5个黄酮类成分含量的差异进行分析,从而初步探索了淫羊藿炮制前后黄酮类成分的变化规律。结合其提取物对MC3T3-E1细胞增殖及成骨能力的影响,发现淫羊藿经盐炙后淫羊藿苷含量增加,对DEX引起的MC3T3-E1细胞成骨抑制的增殖作用显著增强,提示淫羊藿苷可能是淫羊藿不同炮制品抗骨质疏松临床疗效不同的物质基础,为进一步探索淫羊藿炮制原理奠定基础。 展开更多
关键词 淫羊藿 黄酮类化合物 指纹图谱 聚类分析 骨质疏松
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基于SSR标记的葡萄种质指纹图谱构建和遗传多样性分析
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作者 牛锐敏 黄小晶 +3 位作者 沈甜 徐美隆 许泽华 陈卫平 《种子》 北大核心 2025年第4期106-114,共9页
以119份酿酒葡萄和砧木种质资源为试验材料,采用SSR分子标记技术进行DNA指纹图谱构建和遗传多样性分析。结果表明,9对引物共扩增出165个等位基因,各引物扩增出的等位基因数为15~21个,多态性信息含量变化范围为0.81~0.90,平均为0.86。每... 以119份酿酒葡萄和砧木种质资源为试验材料,采用SSR分子标记技术进行DNA指纹图谱构建和遗传多样性分析。结果表明,9对引物共扩增出165个等位基因,各引物扩增出的等位基因数为15~21个,多态性信息含量变化范围为0.81~0.90,平均为0.86。每对引物可以区分14~35个品种,除了同一品种的不同品系用9对引物也无法进行区分外,其余种质用VVMD28+VVMD7+VVMD27等3对引物可以完全区分,最终采用3对SSR引物构建了119份葡萄种质的指纹图谱。UPGMA聚类分析表明,在遗传相似系数0.827处,119份种质可分为三大类:第Ⅰ大类包含欧亚种、欧美杂种、毛葡萄、山葡萄及其衍生酿酒品种共99份葡萄种质;第Ⅱ大类包含河岸葡萄、以河岸葡萄为母本的砧木以及山葡萄为母本、父本含有河岸葡萄的砧木共12份葡萄种质;第Ⅲ大类包含8份以冬葡萄为母本的砧木。聚类结果基本反映了种质间的遗传关系,其中亲缘关系较远的不同类别间及亚类间的种质资源可作为杂交育种的亲本。 展开更多
关键词 葡萄 SSR标记 指纹图谱 遗传多样性
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