期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
基于高分辨率遥感影像的建筑物提取方法综述 被引量:15
1
作者 张亚一 费鲜芸 +2 位作者 王健 王筱雪 陈周 《测绘与空间地理信息》 2020年第4期76-79,共4页
建筑物的提取是地理数据库更新和建设的重要内容,利用高分辨率遥感影像进行建筑物提取是该项研究的重要方向,也是遥感前沿技术研究的重要内容。本文将相关文献进行归纳分析,将建筑物提取方法分为3种有代表性的类型:基于对象分割的提取... 建筑物的提取是地理数据库更新和建设的重要内容,利用高分辨率遥感影像进行建筑物提取是该项研究的重要方向,也是遥感前沿技术研究的重要内容。本文将相关文献进行归纳分析,将建筑物提取方法分为3种有代表性的类型:基于对象分割的提取方法、基于建筑特征的提取方法和结合辅助信息的提取方法,综述分析了每种类型的提取方法并总结了其优缺点,展望了高分辨率遥感影像中建筑物提取的发展前景。 展开更多
关键词 高分辨率影像 建筑物提取 图像自动处理 多特征提取方法
下载PDF
A Multi-model Approach for Soft Sensor Development Based on Feature Extraction Using Weighted Kernel Fisher Criterion 被引量:7
2
作者 吕业 杨慧中 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第2期146-152,共7页
Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenome... Multi-model approach can significantly improve the prediction performance of soft sensors in the process with multiple operational conditions.However,traditional clustering algorithms may result in overlapping phenomenon in subclasses,so that edge classes and outliers cannot be effectively dealt with and the modeling result is not satisfactory.In order to solve these problems,a new feature extraction method based on weighted kernel Fisher criterion is presented to improve the clustering accuracy,in which feature mapping is adopted to bring the edge classes and outliers closer to other normal subclasses.Furthermore,the classified data are used to develop a multiple model based on support vector machine.The proposed method is applied to a bisphenol A production process for prediction of the quality index.The simulation results demonstrate its ability in improving the data classification and the prediction performance of the soft sensor. 展开更多
关键词 feature extraction weighted kernel Fisher criterion CLASSIFICATION soft sensor
下载PDF
Fault Feature Extraction of Rotating Machinery Based on Wavelet Transformation and Multi-resolution Analysis
3
作者 公茂法 刘庆雪 +1 位作者 刘明 张晓丽 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期312-314,共3页
This paper expounded in detail the principle of energy spectrum analysis based on discrete wavelet transformation and multiresolution analysis. In the aspect of feature extraction method study, with investigating the ... This paper expounded in detail the principle of energy spectrum analysis based on discrete wavelet transformation and multiresolution analysis. In the aspect of feature extraction method study, with investigating the feature of impact factor in vibration signals and considering the non-placidity and non-linear of vibration diagnosis signals, the authors import wavelet analysis and fractal theory as the tools of faulty signal feature description. Experimental results proved the validity of this method. To some extent, this method provides a good approach of resolving the wholesome problem of fault feature symptom description. 展开更多
关键词 discrete wavelet transform (DWT) multi-resolution analysis fault diagnosis rotating madchinery feature extraction
下载PDF
Comparative analysis of structural characteristics and cardiomyocyte protective effects of glucomannan extracted from Bletilla striata using varied methods
4
作者 Feng Pan Nan Yang +5 位作者 Guoyong Ruan Changyan Yu Jianbo Yang Dongxue Suo Ying Qin Yun Liu 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2024年第8期686-704,共19页
Doxorubicin(DOX)is a widely employed tumor therapy,yet its substantial toxic side effects pose a considerable challenge.Bletilla striata has demonstrated efficacy in preventing and treating these toxic side effects in... Doxorubicin(DOX)is a widely employed tumor therapy,yet its substantial toxic side effects pose a considerable challenge.Bletilla striata has demonstrated efficacy in preventing and treating these toxic side effects in clinical practice,with polysaccharides identified as the principal active component.In the present study,16 fractions of B.striata polysaccharides(BsPs)were extracted using diverse methods,including hot-water extraction(HWE),ultrasonic-assisted extraction(UAE),enzyme-assisted extraction(EAE),dilute acid-water extraction(ACWE),and dilute alkali-water extraction(ALWE).These extractions were subsequently precipitated at final ethanol concentrations of 80%and 95%,respectively.The investigation encompassed yields,total carbohydrate content(TCC),total protein content(TPC),preliminary structural properties,and anti-DOX myocardial cytotoxic activity.Results indicated that the extraction method significantly influenced the physicochemical properties,associated functional properties,and anti-DOX myocardial cytotoxic activity of BsPs.HWE and UAE yielded higher BsPs quantities.The relative molecular weight(RMW)distribution of BsPs differed notably between HWE or UAE,EAE,ACWE,and ALWE.The RMW of primary BsPs obtained from HWE and UAE(1.9×10^(7)-1.7×10^(7) Da)exceeded that from EAE(7.5×10^(3)-2.8×10^(4) Da)and ALWE(5.1×10^(4)-1.7×10^(4) Da),with smaller molecular weights primarily precipitated by higher ethanol concentrations.BsPs were composed of Man and Glu,with partial fractions containing small amounts of Gal or Ara,displaying varying molar ratios.Notably,BsPs from ACWE exhibited the most significant structural differences,lacking 1,4-α-D-Glcp and a triple-helical structure.Furthermore,BsPs obtained from HWE,UAE,and EAE demonstrated heightened anti-DOX myocardial cytotoxic activity compared to other methods.This study underscored the influence of extraction methods on BsPs’structure and myocardial protective activity,offering a foundation for exploring structural diversity and employing specific extraction methods to extract polysaccharides with robust myocardial protective properties efficiently. 展开更多
关键词 Bletilla striata(Thunb.)Rchb.f. POLYSACCHARIDE Extraction methods Structural characteristics Myocardial protection
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部