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Applicability of P/S amplitude ratios for the discrimination of low magnitude seismic events
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作者 潘常周 靳平 王红春 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第5期553-561,共9页
Applicability of regional P/S amplitude ratios for the discrimination of low-magnitude seismic events was tested and proved using earthquakes and explosions in Central Asia. Results obtained show that regional P/S amp... Applicability of regional P/S amplitude ratios for the discrimination of low-magnitude seismic events was tested and proved using earthquakes and explosions in Central Asia. Results obtained show that regional P/S amplitude ratios which may discriminate medium or large magnitude events well, are also applicable to low magnitude events Their performances for low magnitude events are almost as good as that for medium or large events. Statistical comparisons based on 25 P/S discriminate from the four seismic stations WMQ, BLK, MUL and MAK showed that the average misclassification rate for low-magnitude seismic events averagely was only 2 percent higher than that for medium and large magnitude seismic events. 展开更多
关键词 underground explosions low magnitude discriminant P/s amplitude ratios
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煤层底板突水危险性的Fisher判别分析模型 被引量:58
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作者 张文泉 张广鹏 +1 位作者 李伟 华祥 《煤炭学报》 EI CAS CSCD 北大核心 2013年第10期1831-1836,共6页
为准确评价底板突水危险性,考虑到不同影响因素对于评价方法的作用与影响不同,运用逐步判别法剔除了判别效果不显著的指标,选取了含水层富水性、水压、隔水层厚度、断层导水性、构造发育程度5项主要影响因素作为判别指标。根据以往突水... 为准确评价底板突水危险性,考虑到不同影响因素对于评价方法的作用与影响不同,运用逐步判别法剔除了判别效果不显著的指标,选取了含水层富水性、水压、隔水层厚度、断层导水性、构造发育程度5项主要影响因素作为判别指标。根据以往突水数据建立了底板突水危险性的Fisher判别分析模型,并绘制了判别空间中样本数据散点图。该模型通过了显著性检验,分类效果显著。对15组训练样本进行回代判别,误判率为0,通过距离判别法准确预测了测试样本的突水危险性,表明该模型在煤层底板突水危险性评价上具有较高的可信度和良好的实用性。 展开更多
关键词 煤层 底板 突水 fisher判别 逐步判别 距离判别
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基于Fisher线性判别率的加权K-means聚类算法 被引量:5
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作者 杨鹤标 薛艳锋 +2 位作者 冯进兰 沈项军 吴静丽 《计算机应用研究》 CSCD 北大核心 2010年第12期4439-4442,共4页
为提高K-means聚类效果,采用Fisher线性判别率的方法确定特征在聚类中的贡献度并依此对特征进行加权聚类。在人工和实际数据集上所做的实验表明,本方法在聚类效果上优于其他同类加权K-means聚类算法。
关键词 K-均值 聚类 fisher线性判别率 特征加权 调整随机指标 类内错误率均方和
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阿尔茨海默病和轻度认知损伤诊断的逐步Fisher判别模型 被引量:4
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作者 马翠 周先东 罗万春 《第三军医大学学报》 CAS CSCD 北大核心 2016年第13期1501-1505,共5页
目的建立正确率较高的阿尔茨海默病和轻度认知损伤的诊断模型。方法通过对391例包括正常人、阿尔茨海默病患者以及轻度认知损伤患者的33项临床指标的研究,运用逐步Fisher判别进行诊断模拟,选出正确率最高的判别函数。结果筛选出6项指标... 目的建立正确率较高的阿尔茨海默病和轻度认知损伤的诊断模型。方法通过对391例包括正常人、阿尔茨海默病患者以及轻度认知损伤患者的33项临床指标的研究,运用逐步Fisher判别进行诊断模拟,选出正确率最高的判别函数。结果筛选出6项指标建立了阿尔茨海默病以及轻度认知损伤诊断模型。经过100次随机抽样诊断模拟,对于正常人、轻度认知损伤以及阿尔茨海默病患者诊断的平均正确率达到75.50%,最高正确率达到80.63%。结论逐步Fisher判别诊断模型能提高阿尔茨海默病以及轻度认知损伤的诊断正确率,为科研和临床诊断提供了一种新途径。 展开更多
关键词 阿尔茨海默病 轻度认知损伤 逐步fisher判别
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基于S变换与核Fisher的模拟电路故障诊断 被引量:2
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作者 于辉 谭阳红 关万琳 《计算机测量与控制》 北大核心 2013年第9期2412-2415,共4页
故障特征的有效提取和分类器的设计是模拟电路故障诊断的两个至关重要的环节,为此,提出了一种基于S变换与核fisher相结合的模拟电路故障诊断新方法,首先利用S变换对原始数据进行时频分析,其次利用奇异值分解对提其降维去冗处理,选取最... 故障特征的有效提取和分类器的设计是模拟电路故障诊断的两个至关重要的环节,为此,提出了一种基于S变换与核fisher相结合的模拟电路故障诊断新方法,首先利用S变换对原始数据进行时频分析,其次利用奇异值分解对提其降维去冗处理,选取最佳表示故障的特征量,最后对特征量进行核fisher判别分析,把非线性数据映射到一个高维空间,在高维空间对其进行线性分类处理,完成故障的识别和定位;实例仿真结果表明,该方法能够准确有效地实现故障定位,具有更高的诊断准确率和良好的应用前景。 展开更多
关键词 s变换 fisher 故障诊断 模拟电路
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基于Fisher判别的分布式K-Means聚类算法 被引量:5
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作者 彭长生 《江苏大学学报(自然科学版)》 EI CAS CSCD 北大核心 2014年第4期422-427,共6页
为了解决集中式聚类算法不能处理海量大数据的问题,提出基于Fisher判别确定置信半径的分布式聚类算法.应用网络上各个节点的计算、存储能力,以及网络的带宽,将聚类所需的时间复杂度和空间复杂度平摊到各个节点.通过应用Fisher线性判别... 为了解决集中式聚类算法不能处理海量大数据的问题,提出基于Fisher判别确定置信半径的分布式聚类算法.应用网络上各个节点的计算、存储能力,以及网络的带宽,将聚类所需的时间复杂度和空间复杂度平摊到各个节点.通过应用Fisher线性判别找到节点在同一子类数据上的稠密和稀疏分布,从而快速确定聚类的置信半径并指导下一步的聚类过程,使得保持聚类精度的同时能提高分布式聚类的速度.对算法进行了数值模拟,并使用真实数据完成了试验.结果表明,所提出算法相比DFEKM聚类算法,能根据数据分布的不同在聚类结果和聚类速度上达到很好的平衡,这表明该算法具有更好的健壮性. 展开更多
关键词 P2P网络 聚类算法 分布式聚类 fisher线性判别 置信半径
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基于多约简Fisher-VSM和SVM的文本情感分类 被引量:1
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作者 邢玉娟 谭萍 曹晓丽 《计算机应用与软件》 CSCD 2016年第9期301-305,共5页
为了提高文本情感分类准确率,提出基于多约简Fisher向量空间模型和支持向量机的文本情感分类算法。该算法首先采用Fisher判别准则提取TF-IDF特征向量,然后依据低维文档向量空间模型间的相似度对文档进行聚类,减少文档的数目。该算法从... 为了提高文本情感分类准确率,提出基于多约简Fisher向量空间模型和支持向量机的文本情感分类算法。该算法首先采用Fisher判别准则提取TF-IDF特征向量,然后依据低维文档向量空间模型间的相似度对文档进行聚类,减少文档的数目。该算法从维度和数量两个方面对文档的向量空间模型进行约简,以期提高支持向量机的训练速度和分类性能。仿真实验结果表明,该算法具有良好的召回率和分类准确率。 展开更多
关键词 文本情感分类 fisher判别比 向量空间模型 支持向量机
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Mixed-Fisher特征云模型聚类在文本情感分类中的应用
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作者 邢玉娟 郭显 +1 位作者 谭萍 李明 《计算机科学与探索》 CSCD 北大核心 2016年第9期1320-1331,共12页
海量网络信息的出现,使得提取文本信息情感观点成为研究的热点。针对文本情感分类中文本信息模糊及分类准确率低的问题,提出了一种基于Mixed-Fisher特征选择的文本云向量模型聚类算法。该算法首先分别计算文档中各个词性特征项的Fisher... 海量网络信息的出现,使得提取文本信息情感观点成为研究的热点。针对文本情感分类中文本信息模糊及分类准确率低的问题,提出了一种基于Mixed-Fisher特征选择的文本云向量模型聚类算法。该算法首先分别计算文档中各个词性特征项的Fisher判别比,根据Fisher判别比越大特征向量判别性越强的Fisher准则,选择Fisher比值较大的前q个特征,并按照词性进行组合生成文档的Mixed-Fisher特征向量。然后在Mixed-Fisher特征向量集上构建文档的云向量模型,根据云向量模型间的差异度对模型进行聚类和合并。将该算法应用于文本情感观点的分类,选择核Fisher判别技术用于最终文本观点的判定。仿真实验结果表明,基于Mixed-Fisher特征的云向量聚类模型的分类准确率明显优于传统向量空间模型,从而验证了核Fisher判别技术的有效性。 展开更多
关键词 文本情感分类 fisher判别比 词性特征 云向量模型 fisher判别
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基于Fisher判别函数的酒店员工离职预警研究 被引量:1
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作者 张侨 《琼州学院学报》 2014年第2期109-115,共7页
基于马氏距离平方,构建了Fisher判别函数,应用Fisher判别函数对酒店员工离职数据进行模拟判别,验证了判别函数在识别员工离职倾向上的有效性;根据被调查的6位员工的满意度数据,对他们的离职倾向进行了预测.
关键词 fisher判别函数 员工离职 离职预警
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Failure mode classification of reinforced concrete column using Fisher method 被引量:11
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作者 戚永乐 韩小雷 季静 《Journal of Central South University》 SCIE EI CAS 2013年第10期2863-2869,共7页
In order to apply the performance-based seismic design, an engineer must first find out whether the column is expected to fail in shear before or after flexural yielding. According to column failure characteristics an... In order to apply the performance-based seismic design, an engineer must first find out whether the column is expected to fail in shear before or after flexural yielding. According to column failure characteristics and failure mode of reinforced concrete column, the UW-PEER structure performance database was discussed and analyzed. In order to investigate the relevance of failure mode and factors such as longitudinal reinforcement ratio, transverse reinforcement ratio, hoop spacing to depth ratio, aspect ratio, shearing resistance demand to shear capacity ratio and axial load ratio, Fisher's discriminant analysis(FDA) of the above factors was carried out. A discriminant function was developed to identify column failure mode. Results show that three factors, i.e., Vp /Vn, hoop spacing to depth ratio and aspect ratio have important influence on the failure mode. The failure mode has less to do with longitudinal reinforcement ratio, transverse reinforcement ratio and axial load ratio. Through using these three factors and the model proposed, over 85.6% of the original grouped cases were correctly classified. The value of coefficient of Vp /Vn is the largest, which means that discriminant equation is most sensitive to the shearing resistance demand to shear capacity ratio. 展开更多
关键词 fishers discriminant analysis(FDA) concrete COLUMN FAILURE mode identification performance-based sEIsMIC design
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Calibration of P/S amplitude ratios for seismic events in Xinjiang and its adjacent areas based on a Bayesian Kriging method
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作者 潘常周 靳平 肖卫国 《Acta Seismologica Sinica(English Edition)》 CSCD 2007年第6期664-674,共11页
Correction maps of P/S amplitude ratios for seismic events distributed in Xinjiang, China and its adjacent areas were established using a Bayesian Kriging method for the two seismic stations WMQ and MAK. The relations... Correction maps of P/S amplitude ratios for seismic events distributed in Xinjiang, China and its adjacent areas were established using a Bayesian Kriging method for the two seismic stations WMQ and MAK. The relationship between correction maps and variations of along-path features was analyzed and the validity of applying the correction maps to improve performances of P/S discriminants for seismic discrimination was investigated. Results show that obtained correction maps can generally reflect event-station path effects upon corresponding P/S discriminants; and the correction of these effects could further reduce scatters of distance-corrected P/S measurements within earthquake and explosion populations as well as improve their discriminating performances if path effects are a significant factor of such scatters. For example, as corresponding Kriging correction map was applied, the misidentification rate of earthquakes by Pn(2-4 Hz)/Lg(2-4 Hz) at MAK was reduced from 16.3% to 5.2%. 展开更多
关键词 seismic events discriminATION KRIGING P/s amplitude ratios
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Multispectral Imaging in Combination with Multivariate Analysis Discriminates Selenite Induced Cataractous Lenses from Healthy Lenses of Sprague-Dawley Rats
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作者 Peter Osei-Wusu Adueming Moses Jojo Eghan +5 位作者 Benjamin Anderson Samuel Kyei Jerry Opoku-Ansah Charles L. Y. Amuah Samuel Sonko Sackey Paul Kingsley Buah-Bassuah 《Open Journal of Biophysics》 2017年第3期145-156,共12页
Cataracts are the leading cause of blindness worldwide. Current methods for discriminating cataractous lenses from healthy lenses of Sprague-Dawley rats during preclinical studies are based on either histopathological... Cataracts are the leading cause of blindness worldwide. Current methods for discriminating cataractous lenses from healthy lenses of Sprague-Dawley rats during preclinical studies are based on either histopathological or clinical assessments which are weakened by subjectivity. In this work, both cataractous and healthy lens tissues of Sprague-Dawley rats were studied using multispectral imaging technique in combination with multivariate analysis. Multispectral images were captured in transmission, reflection and scattering modes. In all, five spectral bands were found to be markers for discriminating cataractous lenses from healthy lenses;470 nm and 625 nm discriminated in reflection mode whereas 435 nm, 590 nm and 700 nm discriminated in transmission mode. With Fisher’s Linear discriminant analysis, the midpoints for classifying cataractous from healthy lenses were found to be 14.718 × 10&minus;14 and 3.2374 × 10&minus;14 for the two spectra bands in the reflection mode and the three spectral bands in the transmission mode respectively. Images in scattering mode did not show significant discrimination. These spectral bands in reflection and transmission modes may offer potential diagnostic markers for discriminating cataractous lenses from healthy lenses thereby promising multispectral imaging applications for characterizing cataractous and healthy lenses. 展开更多
关键词 MULTIsPECTRAL Imaging Cataractous Lenses Principal Component ANALYsIs fishers Linear discriminant ANALYsIs
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基于实验室常规指标建立肝纤维化Fisher判别模型
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作者 谢康生 郑兰兰 +1 位作者 贾春红 苏建平 《胃肠病学和肝病学杂志》 CAS 2013年第10期983-986,共4页
目的利用实验室常规指标建立慢性乙型肝炎(chronic hepatitis B,CHB)患者的肝纤维化诊断模型,寻找肝穿刺活检的非创性替代手段。方法选取174例CHB患者,行肝活检组织学分期(S),检测血清肝纤维化和肝功能指标,Spearman等级相关法分析肝活... 目的利用实验室常规指标建立慢性乙型肝炎(chronic hepatitis B,CHB)患者的肝纤维化诊断模型,寻找肝穿刺活检的非创性替代手段。方法选取174例CHB患者,行肝活检组织学分期(S),检测血清肝纤维化和肝功能指标,Spearman等级相关法分析肝活检组织学分期与实验室指标的关系,建立Fisher判别模型,回代法验证模型的诊断性能。结果 (1)肝纤维化组织学分期(S0→S4)与透明质酸(HA,r=0.569)、层黏连蛋白(LN,r=0.428)、血清Ⅲ型前胶原(PC-Ⅲ,r=0.405)、Ⅳ型胶原(C-Ⅳ,r=0.395)、丙氨酸氨基转移酶(ALT,r=0.445)、天冬氨酸氨基转移酶(AST,r=0.412)、γ-谷氨酰转肽酶(γ-GT,r=0.317)、总胆红素(TB,r=0.396)呈正相关,与血小板(PLT,r=-0.427)、血清白蛋白(ALB,r=-0.382)呈负相关(P<0.05或P<0.001)。(2)Fisher逐步判别分析显示,LN、HA、ALT、PLT入选以肝组织学分期为结果变量的判别函数,判别函数式:①Function 1=0.006HA+0.016LN+0.003ALT-0.007PLT-2.636;②Function 2=0.007LN+0.004ALT+0.021PLT-4.763。(3)函数诊断无纤维化(S0)、肝纤维化(S1~S3)和肝硬化(S4)的灵敏度分别是75.00%、78.30%和77.50%,总体一致率为77.59%,Kappa=0.610。结论基于实验室常规指标建立的Fisher判别模型,能为CHB患者肝纤维化分期的判断提供中等强度的诊断效能,可部分替代肝活检。 展开更多
关键词 乙型肝炎病毒 肝纤维化 血清标志物 fisher判别 诊断
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P/S震相幅值比判据对低震级地震事件的适用性检验 被引量:19
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作者 潘常周 靳平 王红春 《地震学报》 CSCD 北大核心 2007年第5期521-528,共8页
基于中国新疆及中亚地区大量天然地震和地下爆炸,检验了较大震级情况下得到的区域P/S震相幅值比识别判据对低震级地震事件的适用性.分析结果表明,对较大震级地震事件具有较好识别效果的P/S震相幅值比判据对低震级事件同样适用,而且对低... 基于中国新疆及中亚地区大量天然地震和地下爆炸,检验了较大震级情况下得到的区域P/S震相幅值比识别判据对低震级地震事件的适用性.分析结果表明,对较大震级地震事件具有较好识别效果的P/S震相幅值比判据对低震级事件同样适用,而且对低震级事件也具有与较大震级事件大致相当的识别效果.据WMQ、BLK、MUL和MAK台的25个识别效果较好的P/S震相幅值比判据统计,大于ML3.5和ML3.5以下地震事件的误识率之差约为2个百分点. 展开更多
关键词 地下爆炸 低震级 识别判据 P/s震相幅值比
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利用克里金技术标定新疆及附近地区P/S震相幅值比及其在地震事件识别中的应用 被引量:9
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作者 潘常周 靳平 肖卫国 《地震学报》 CSCD 北大核心 2007年第6期625-634,共10页
针对中国的乌鲁木齐台(WMQ)和哈萨克斯坦的马坎奇台(MAK),采用贝叶斯克里金技术建立了新疆及附近地区地震事件的P/S震相幅值比的校正曲面,并分析了校正曲面与地震波传播路径的关系,以及校正曲面对于改善P/S震相幅值比判据识别... 针对中国的乌鲁木齐台(WMQ)和哈萨克斯坦的马坎奇台(MAK),采用贝叶斯克里金技术建立了新疆及附近地区地震事件的P/S震相幅值比的校正曲面,并分析了校正曲面与地震波传播路径的关系,以及校正曲面对于改善P/S震相幅值比判据识别效果的有效性.分析结果表明,建立的校正曲面基本合理,结合传播路径差异和地震波传播规律,能够较好地解释校正曲面的起伏特征.而且,在传播路径差异较大,使得P/S震相幅值比经震中距校正后离散度仍然较高的情况下,利用校正曲面修正P/S震相幅值比,可以进一步降低其离散度,从而改善判据的识别效果.MAK台lg[Pn(2~4Hz)/Lg(2~4Hz)]校正曲面修正后,对天然地震的误识率由16.3%下降为5.2%. 展开更多
关键词 地震事件 识别 克里金 P/s震相幅值比
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A WEIGHTED FEATURE REDUCTION METHOD FOR POWER SPECTRA OF RADAR HRRPS 被引量:1
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作者 Du Lan Liu Hongwei Bao Zheng Zhang Junying 《Journal of Electronics(China)》 2006年第3期365-369,共5页
Feature reduction is a key process in pattern recognition. This paper deals with the feature reduction methods for a time-shift invariant feature, power spectrum, in Radar Automatic Target Recognition (RATR) using Hig... Feature reduction is a key process in pattern recognition. This paper deals with the feature reduction methods for a time-shift invariant feature, power spectrum, in Radar Automatic Target Recognition (RATR) using High-Resolution Range Profiles (HRRPs). Several existing feature reduction methods in pattern recognition are analyzed, and a weighted feature reduction method based on Fisher's Discriminant Ratio (FDR) is proposed in this paper. According to the characteristics of radar HRRP target recognition, this proposed method searches the optimal weight vector for power spectra of HRRPs by means of an iterative algorithm, and thus reduces feature dimensionality. Compared with the method of using raw power spectra and some existing feature reduction methods, the weighted feature reduction method can not only reduce feature dimensionality, but also improve recognition performance with low computation complexity. In the recognition experiments based on measured data, the proposed method is robust to different test data and achieves good recognition results. 展开更多
关键词 Radar Automatic Target Recognition (RATR) High-Resolution Range Profile (HRRP) Power spectrum Feature reduction fisher's discriminant ratio (FDR)
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Automatic detection of pulse morphology patterns &cardiac risks
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作者 Rajani R. Joshi Ganesh B. Nawsupe Smita P. Wangikar 《Journal of Biomedical Science and Engineering》 2012年第6期315-322,共8页
Analysis of arterial pulse waveforms is important for non-invasive diagnosis of cardiovascular functions. Large samples of IPG signal records of radial arterial pulse show presence of eight different types of shapes (... Analysis of arterial pulse waveforms is important for non-invasive diagnosis of cardiovascular functions. Large samples of IPG signal records of radial arterial pulse show presence of eight different types of shapes (morphological patterns) in the pulse waveforms. In this paper we present an efficient computational method for automatic identification of these morphological patterns. Our algorithm uses likelihood ratio of cumulative periodogram of pulse signals and some geometrical criteria. The algorithm is presented with necessary details on signal processing aspects. Results for a large sample of pulse records of adult Indian subjects show high accuracy of our algorithm in detecting pulse-morphology patterns. Variation of pulse-morphology with respect to time is also analyzed using this algorithm. We have identified some characteristic features of pulse-morphology variation in patients of certain cardiac problems, hypertension, and diabetes. These are found relevant and significant in terms of physiological interpretation of the associated shapes of pulse waveforms. Importance of these findings is highlighted along with discussion on overall scope of our study in automatic analysis of heart rate variability and in other applications for non-invasive prognosis/diagnosis. 展开更多
关键词 PULsE signal sPECTRAL Analysisfishers ratio MORPHOLOGY Variation GEOMETRICAL Modeling
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Combining Likelihood Information from Independent Investigations
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作者 L. Jiang A. Wong 《Open Journal of Statistics》 2015年第1期51-59,共9页
Fisher [1] proposed a simple method to combine p-values from independent investigations without using detailed information of the original data. In recent years, likelihood-based asymptotic methods have been developed... Fisher [1] proposed a simple method to combine p-values from independent investigations without using detailed information of the original data. In recent years, likelihood-based asymptotic methods have been developed to produce highly accurate p-values. These likelihood-based methods generally required the likelihood function and the standardized maximum likelihood estimates departure calculated in the canonical parameter scale. In this paper, a method is proposed to obtain a p-value by combining the likelihood functions and the standardized maximum likelihood estimates departure of independent investigations for testing a scalar parameter of interest. Examples are presented to illustrate the application of the proposed method and simulation studies are performed to compare the accuracy of the proposed method with Fisher’s method. 展开更多
关键词 CANONICAL Parameter fishers EXPECTED Information Modified sIGNED Log-Likelihood ratio statistic standardized Maximum LIKELIHOOD Estimate DEPARTURE
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复杂礁滩气藏储层流体测井识别技术 被引量:8
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作者 胡碟 贺洪举 +1 位作者 朱占美 杨东凡 《天然气工业》 EI CAS CSCD 北大核心 2012年第1期49-52,121-122,共4页
礁滩气藏的储层非均质性强,具有低孔隙度、高电阻值和岩性复杂等特征,其流体的测井识别一直面临着较大的困难。为此,针对不同的储层岩性和储集空间类型建立针对性的判别模型,以四川盆地龙岗礁滩气藏储层流体识别为研究对象,在对目前国... 礁滩气藏的储层非均质性强,具有低孔隙度、高电阻值和岩性复杂等特征,其流体的测井识别一直面临着较大的困难。为此,针对不同的储层岩性和储集空间类型建立针对性的判别模型,以四川盆地龙岗礁滩气藏储层流体识别为研究对象,在对目前国内外已有的碳酸盐岩储层测井流体识别方法———电阻率法、孔隙度重叠法、P1/2法等11种方法进行深入分析研究的基础上,优选出了3种适合龙岗地区复杂礁滩气藏流体识别的方法(即电阻率法、中子和声波信息组合法、纵横波信息法);此外,在分层位、分岩性开展岩电试验和纵横波速度对比试验的基础上,对这3种方法进行了改进,建立起了该区礁滩气藏储层的流体判别技术,使流体识别符合率从78%提高到了90%,为复杂碳酸盐岩储层的流体识别提供了技术支持。 展开更多
关键词 复杂礁滩气藏 流体 判别 电阻率 中子 声波 纵横波速度比 泊松比
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pH-区带精制逆流色谱分离高F值寡肽新技术研究 被引量:6
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作者 秦秋香 魏东 郭祀远 《天然产物研究与开发》 CAS CSCD 2008年第5期866-869,883,共5页
高F值寡肽是一种由2~8个氨基酸组成的生理活性肽。本研究采用胃蛋白酶和O/一胰凝乳蛋白酶对草鱼蛋白进行了两步酶解,高效液相色谱对酶解液进行了肽谱分析,以制备改善肝性脑病的高F值寡肽。结果表明,草鱼蛋白酶解液中含有高支低芳... 高F值寡肽是一种由2~8个氨基酸组成的生理活性肽。本研究采用胃蛋白酶和O/一胰凝乳蛋白酶对草鱼蛋白进行了两步酶解,高效液相色谱对酶解液进行了肽谱分析,以制备改善肝性脑病的高F值寡肽。结果表明,草鱼蛋白酶解液中含有高支低芳氨基酸的寡肽组分,开发一种pH一区带精制逆流色谱分离新技术,所用体系为甲基叔丁基醚:正丁醇:乙腈:水(2:2:1:5,V/V/V/V),上相中加入20mM三乙胺和20%磷酸二(2-乙基己基)酯(DEHPA)作为固定相,下相分两部分,分别加入10mM HCl和20m MHCl作为流动相,进行梯度洗脱。成功地对酶解液中的混合组分进行了分离,得到了5个高F值(F〉20)的分离组分,估测其F值(F=OD214nm/OD280nm)高达24.7—36.4。该结果为利用低值鱼蛋白酶解制备功能性活性肽提供了新的制备方法。 展开更多
关键词 高F值寡肽 酶解 pH-区带精制逆流色谱 肽谱分析
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