期刊文献+
共找到13,323篇文章
< 1 2 250 >
每页显示 20 50 100
A dual-approach to genomic predictions:leveraging convolutional networks and voting classifiers
1
作者 Raghad K.Mohammed Azmi Tawfeq Hussein Alrawi Ali Jbaeer Dawood 《Biomedical Engineering Communications》 2025年第1期3-11,共9页
Background:In the field of genetic diagnostics,DNA sequencing is an important tool because the depth and complexity of this field have major implications in light of the genetic architectures of diseases and the ident... Background:In the field of genetic diagnostics,DNA sequencing is an important tool because the depth and complexity of this field have major implications in light of the genetic architectures of diseases and the identification of risk factors associated with genetic disorders.Methods:Our study introduces a novel two-tiered analytical framework to raise the precision and reliability of genetic data interpretation.It is initiated by extracting and analyzing salient features from DNA sequences through a CNN-based feature analysis,taking advantage of the power inherent in Convolutional neural networks(CNNs)to attain complex patterns and minute mutations in genetic data.This study embraces an elite collection of machine learning classifiers interweaved through a stern voting mechanism,which synergistically joins the predictions made from multiple classifiers to generate comprehensive and well-balanced interpretations of the genetic data.Results:This state-of-the-art method was further tested by carrying out an empirical analysis on a variants'dataset of DNA sequences taken from patients affected by breast cancer,juxtaposed with a control group composed of healthy people.Thus,the integration of CNNs with a voting-based ensemble of classifiers returned outstanding outcomes,with performance metrics accuracy,precision,recall,and F1-scorereaching the outstanding rate of 0.88,outperforming previous models.Conclusions:This dual accomplishment underlines the transformative potential that integrating deep learning techniques with ensemble machine learning might provide in real added value for further genetic diagnostics and prognostics.These results from this study set a new benchmark in the accuracy of disease diagnosis through DNA sequencing and promise future studies on improved personalized medicine and healthcare approaches with precise genetic information. 展开更多
关键词 CNN DNA sequencing ensemble machine learning genetic disease voting classifier
在线阅读 下载PDF
构建含毒性成分中成药安全性风险警示分类管理体系——以乌头类成分为例
2
作者 常星洁 郭红叶 +2 位作者 齐明月 石璠钰 金锐 《医药导报》 北大核心 2026年第1期76-83,共8页
目的以含乌头类成分中成药为例,构建含毒性成分中成药风险警示分类管理体系。方法以《国家基本医疗保险、工伤保险和生育保险药品目录(2024)》中含乌头类成分的中成药品种为例建立数据库,统计其剂型及制备工艺,计算乌头类成分日服用剂量... 目的以含乌头类成分中成药为例,构建含毒性成分中成药风险警示分类管理体系。方法以《国家基本医疗保险、工伤保险和生育保险药品目录(2024)》中含乌头类成分的中成药品种为例建立数据库,统计其剂型及制备工艺,计算乌头类成分日服用剂量,运用“汤液经法图”对其药味配伍结构进行分析,并综合以上3个因素进行风险评估量表评价,按照风险评分结构对构建品种风险警示分级管理。结果共纳入中成药58个品种,剂型共涉及5种,以丸剂最多(占44.83%);制备工艺以原粉入药(67.24%)和水煎煮(27.59%)为主。以最大日服用量计,16个品种乌头碱理论含量存在中毒风险。目前有12个品种有不良反应相关报告,其中8个品种中成药的组方结构以辛味为主(辛味药占比>50%)。通过以上“制剂工艺-日服用剂量-组方药味结构”3个核心要素,构建“3类7项”风险评估指标,并以小金胶囊和桂附地黄丸为例对风险评估量表的合理性进行了验证,最终将纳入品种进行高、中、低3个风险等级的分级管理。结论工艺、剂量、配伍结构均对乌头类中成药的安全性和有效性有重要影响,该研究构建的“三位一体”风险评估体系可为含毒中成药的安全性评价和风险警示分类管理提供参考。 展开更多
关键词 乌头碱 中成药 汤液经法图 分类管理
暂未订购
论语言职业
3
作者 李艳 贺宏志 《语言战略研究》 北大核心 2026年第1期17-28,共12页
“语言职业”是以供给语言产品与服务作为从业人员生活来源的社会工作类别。根据工作成果是否语言产品,以及工作任务的完成是否对语言文字表达具有较强的依赖,可将语言职业划分为“典型语言职业”和“准语言职业”;此外,还有一些职业提... “语言职业”是以供给语言产品与服务作为从业人员生活来源的社会工作类别。根据工作成果是否语言产品,以及工作任务的完成是否对语言文字表达具有较强的依赖,可将语言职业划分为“典型语言职业”和“准语言职业”;此外,还有一些职业提供“伴随式语言服务”。本文从《中华人民共和国职业分类大典(2022版)》和语言行业两个角度,对《大典》已经收录的语言职业和可由此推导出的语言职业进行梳理,并构建了包含3个层面的语言职业研究基本框架,由下而上分别为职业状况研究、动力机制研究、发展策略研究。在此基础上提出如下建议:对从业者已有一定规模,但《大典》尚未收录的语言职业,应予以补充认定,并积极培育新兴语言职业;以语言职业能力研究为切入点,构建语言职业标准体系;以语言职业状况调查为着力点,全面掌握当前中国语言职业现状;建设全国语言职业数据库,服务语言人才培养和语言产业规划。 展开更多
关键词 语言产业 语言职业 职业分类 语言职业研究
在线阅读 下载PDF
Knowledge discovery method for feature-decision level fusion of multiple classifiers 被引量:1
4
作者 孙亮 韩崇昭 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期222-227,共6页
To improve the performance of the multiple classifier system, a new method of feature-decision level fusion is proposed based on knowledge discovery. In the new method, the base classifiers operate on different featur... To improve the performance of the multiple classifier system, a new method of feature-decision level fusion is proposed based on knowledge discovery. In the new method, the base classifiers operate on different feature spaces and their types depend on different measures of between-class separability. The uncertainty measures corresponding to each output of each base classifier are induced from the established decision tables (DTs) in the form of mass function in the Dempster-Shafer theory (DST). Furthermore, an effective fusion framework is built at the feature-decision level on the basis of a generalized rough set model and the DST. The experiment for the classification of hyperspectral remote sensing images shows that the performance of the classification can be improved by the proposed method compared with that of plurality voting (PV). 展开更多
关键词 multiple classifier fusion knowledge discovery Dempster-Shafer theory generalized rough set HYPERSPECTRAL
在线阅读 下载PDF
RankXLAN:An explainable ensemble-based machine learning framework for biomarker detection,therapeutic target identification,and classification using transcriptomic and epigenomic stomach cancer data
5
作者 Kasmika Borah Himanish Shekhar Das +1 位作者 Mudassir Khan Saurav Mallik 《Medical Data Mining》 2026年第1期13-31,共19页
Background:Stomach cancer(SC)is one of the most lethal malignancies worldwide due to late-stage diagnosis and limited treatment.The transcriptomic,epigenomic,and proteomic,etc.,omics datasets generated by high-through... Background:Stomach cancer(SC)is one of the most lethal malignancies worldwide due to late-stage diagnosis and limited treatment.The transcriptomic,epigenomic,and proteomic,etc.,omics datasets generated by high-throughput sequencing technology have become prominent in biomedical research,and they reveal molecular aspects of cancer diagnosis and therapy.Despite the development of advanced sequencing technology,the presence of high-dimensionality in multi-omics data makes it challenging to interpret the data.Methods:In this study,we introduce RankXLAN,an explainable ensemble-based multi-omics framework that integrates feature selection(FS),ensemble learning,bioinformatics,and in-silico validation for robust biomarker detection,potential therapeutic drug-repurposing candidates’identification,and classification of SC.To enhance the interpretability of the model,we incorporated explainable artificial intelligence(SHapley Additive exPlanations analysis),as well as accuracy,precision,F1-score,recall,cross-validation,specificity,likelihood ratio(LR)+,LR−,and Youden index results.Results:The experimental results showed that the top four FS algorithms achieved improved results when applied to the ensemble learning classification model.The proposed ensemble model produced an area under the curve(AUC)score of 0.994 for gene expression,0.97 for methylation,and 0.96 for miRNA expression data.Through the integration of bioinformatics and ML approach of the transcriptomic and epigenomic multi-omics dataset,we identified potential marker genes,namely,UBE2D2,HPCAL4,IGHA1,DPT,and FN3K.In-silico molecular docking revealed a strong binding affinity between ANKRD13C and the FDA-approved drug Everolimus(binding affinity−10.1 kcal/mol),identifying ANKRD13C as a potential therapeutic drug-repurposing target for SC.Conclusion:The proposed framework RankXLAN outperforms other existing frameworks for serum biomarker identification,therapeutic target identification,and SC classification with multi-omics datasets. 展开更多
关键词 stomach cancer BIOINFORMATICS ensemble learning classifier BIOMARKER targets
在线阅读 下载PDF
基于改进辅助分类生成对抗网络的小样本轴承故障诊断
6
作者 谢莹 刘雪伟 鲁振杰 《轴承》 北大核心 2026年第1期100-110,共11页
针对实际工业生产中故障数据较难采集,而训练具有良好性能的深度学习模型又依赖于大量数据样本的问题,提出一种改进辅助分类生成对抗网络与注意力机制相结合(M-ACGAN-A)的故障诊断模型。首先,对振动信号进行短时傅里叶变换,将其转化为... 针对实际工业生产中故障数据较难采集,而训练具有良好性能的深度学习模型又依赖于大量数据样本的问题,提出一种改进辅助分类生成对抗网络与注意力机制相结合(M-ACGAN-A)的故障诊断模型。首先,对振动信号进行短时傅里叶变换,将其转化为二维时频图,从而增强数据特征;其次,采用辅助分类生成对抗网络(ACGAN)的生成器学习实际数据样本的分布,生成大量模拟数据样本;然后,利用嵌入注意力机制的分类器进行模型训练,引入Wasserstein距离指导模型缩短源分布与目标分布的差距,并通过谱归一化来防止模型梯度爆炸;最后,利用训练完成的判别器进行故障诊断。采用凯斯西储大学轴承数据集和帕德博恩大学轴承数据集进行试验,结果表明所提模型能够利用有限的数据信息实现故障诊断,相比于其他深度学习模型具有更高的诊断精度和泛化性。 展开更多
关键词 滚动轴承 故障诊断 特征提取 傅里叶变换 小样本 辅助分类生成对抗网络
在线阅读 下载PDF
Classification performance of model coal mill classifiers with swirling and non-swirling inlets 被引量:6
7
作者 Lele Feng Hai Zhang +4 位作者 Lilin Hu Yang Zhang Yuxin Wu Yuzhao Wang Hairui Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第3期777-784,共8页
The classification performance of model coal mill classifiers with different bottom incoming flow inlets was experimentally and numerically studied.The flow field adjacent to two neighboring impeller blades was measur... The classification performance of model coal mill classifiers with different bottom incoming flow inlets was experimentally and numerically studied.The flow field adjacent to two neighboring impeller blades was measured using the particle image velocimetry technique.The results showed that the flow field adjacent to two neighboring blades with the swirling inlet was significantly different from that with the non-swirling inlet.With the swirling inlet,there was a vortex located between two neighboring blades,while with the nonswirling inlet,the vortex was attached to the blade tip.The vorticity of the vortex with the non-swirling inlet was much lower than that with the swirling inlet.The classifier with the non-swirling inlet demonstrated a larger cut size than that with the swirling inlet when the impeller was stationary(~0 r·min-1).As the impeller rotational speed increased,the cut size of the cases with non-swirling and swirling inlets both decreased,and the one with the non-swirling inlet decreased more dramatically.The values of the cut size of the two classifiers were close to each other at a high impeller rotational speed(≥120 r·min-1).The overall separation efficiency of the classifier with the non-swirling inlet was lower than that with the swirling inlet,and monotonically increased as the impeller rotational speed increased.With the swirling inlet,the overall separation efficiency first increased with the impeller rotational speed and then decreased when the rotational speed was above 120 r·min-1,and the variation trend of the separation efficiency was more moderate.As the initial particle concentration increased,the cut sizes of both swirling and non-swirling inlet cases decreased first and then barely changed.At a low initial particle concentration(b 0.04 kg·m-3),the classifier with the swirling inlet had a larger cut size than that with the non-swirling inlet. 展开更多
关键词 Coal mill classifier Cut size Non-swirling inlet Particle image velocimetry Impeller rotational speed
在线阅读 下载PDF
An Alignment-Based Approach to L2 Learning of Chinese Numeral Classifiers 被引量:5
8
作者 Chuming WANG Wei HONG 《Chinese Journal of Applied Linguistics》 2021年第3期335-350,431,共17页
This study investigated the efficiency of learning the Chinese numeral classifiers by L2 Chinese learners by means of an alignment-oriented task. Participants were a total of 96 intermediate learners of L2 Chinese, wh... This study investigated the efficiency of learning the Chinese numeral classifiers by L2 Chinese learners by means of an alignment-oriented task. Participants were a total of 96 intermediate learners of L2 Chinese, who were randomly assigned to two experimental groups and one control group, with each group consisting of 32 participants. The continuation task used in this study consisted of a picture-based Chinese text depicting a room with an array of objects, which necessitates the use of classifiers. The two experimental groups were both required to first read the text and then write to describe their own rooms in comparison with the one in the text. One group was instructed to use the classifiers from the text as much as possible in their writing, whereas the other was not required to do so. Participants in the control group were first given the picture to look at in the absence of the text and then asked to describe their own rooms. The results showed that the continuation task significantly enhanced participants’ retention of the Chinese numeral classifiers, suggesting that the alignment-based approach is an effective way to learn difficult linguistic categories such as the Chinese classifiers. 展开更多
关键词 ALIGNMENT interaction continuation task learn-together-use-together(LTUT)principle classifiers
在线阅读 下载PDF
Flow Field Characteristics of the Rotor Cage in Turbo Air Classifiers 被引量:2
9
作者 GUO Lijie LIU Jiaxiang LIU Shengzhao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第3期426-432,共7页
The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air class... The turbo air classifier is widely used powder classification equipment in a variety of fields. The flow field characteristics of the turbo air classifier are important basis for the improvement of the turbo air classifier's structural design. The flow field characteristics of the rotor cage in turbo air classifiers were investigated trader different operating conditions by laser Doppler velocimeter(LDV), and a measure diminishing the axial velocity is proposed. The investigation results show that the tangential velocity of the air flow inside the rotor cage is different from the rotary speed of the rotor cage on the same measurement point due to the influences of both the negative pressure at the exit and the rotation of the rotor cage. The tangential velocity of the air flow likewise decreases as the radius decreases in the case of the rotor cage's low rotary speed. In contrast, the tangential velocity of the air flow increases as the radius decreases in the case of the rotor cage's high rotary speed. Meanwhile, the vortex inside the rotor cage is found to occur near the pressure side of the blade when the rotor cage's rotary speed is less than the tangential velocity of air flow. On the contrary, the vortex is found to occur near the blade suction side once the rotor cage's rotary speed is higher than the tangential velocity of air flow. Inside the rotor cage, the axial velocity could not be disregarded and is largely determined by the distances between the measurement point and the exit. 展开更多
关键词 turbo air classifier rotor cage flow field characteristic laser Doppler velocimeter(LDV)
在线阅读 下载PDF
探析《伤寒论》中小柴胡汤“方证群体性”辨治体系
10
作者 白丽露 邵玉雪 +1 位作者 肖文冲 周素芳 《河南中医》 2026年第1期1-6,共6页
小柴胡汤在《伤寒论》中所对应的并非一个单一、僵化的证候,而是一个以“少阳枢机不利”为核心病机、具有丰富临床表现和动态演变规律的“证候群体”,此群体有其核心主证与外围或然证,有其相对稳定的共性特征与个体化的差异表现,并与他... 小柴胡汤在《伤寒论》中所对应的并非一个单一、僵化的证候,而是一个以“少阳枢机不利”为核心病机、具有丰富临床表现和动态演变规律的“证候群体”,此群体有其核心主证与外围或然证,有其相对稳定的共性特征与个体化的差异表现,并与他经病证存在着传变、兼夹的复杂关系。其一,小柴胡汤之用非独少阳一域,更广泛涉及太阳、阳明、厥阴、瘥后等多经病证;其二,小柴胡汤衍生方虽证候繁杂、药物加减不一,然皆以“少阳枢机不利”为核心病机,体现“方随证转,药随病易”的辨治思想,论证了《伤寒论》条文间相互关联的整体性。张仲景“但见一证便是,不必悉具”之训,实为摒弃机械的证候罗列,直指“少阳枢机不利”这一共同病机本质,是以动态、全局的思维去捕捉病机关键,其精髓在于对病机共性的高度概括与临证运用的灵活变通之统一。“方证群体性”理论的提出,拓展了经方应用的思维模式,使其从“一证一方”的对应框架转向对病机共性的整体把握。临床不必拘泥于某一固定证型,关键在于抓住“少阳枢机不利”这一核心病机,洞察气机在升降出入过程中的郁滞、失宣或逆乱等异常状态。如此,即便症状表现复杂多样,亦可执简驭繁,以柴胡类方为基础,通过适当化裁,应对多种病症,实现“异病同治”的经方运用新范式。 展开更多
关键词 小柴胡汤 “方证群体性” 《伤寒论》 张仲景 正证群体 变证群体 类证群体 疑似证群体 少阳主证 柴胡汤类方 泻心汤类方 麦门冬汤类方
暂未订购
高校分类改革的规制与推进
11
作者 史秋衡 赵瑾奕 《高校教育管理》 北大核心 2026年第1期58-68,共11页
推进高校分类改革是教育体制改革的核心命题,发挥其龙头作用需构建贯通发展脉络、战略依据与标志探索的三维规制框架。高校管理的理路传承、内涵式发展的内在规律及时代变革的问题导向,共同构成分类改革的逻辑基点。宏观政策调控与多元... 推进高校分类改革是教育体制改革的核心命题,发挥其龙头作用需构建贯通发展脉络、战略依据与标志探索的三维规制框架。高校管理的理路传承、内涵式发展的内在规律及时代变革的问题导向,共同构成分类改革的逻辑基点。宏观政策调控与多元主体协同的辩证统一,形塑我国高等教育分类发展的战略。未来高校分类改革要构建自主分类知识体系,以创新驱动关键产业;实现国家顶层设计与政府引领下多元分类共治的有机衔接;依托高校组间差异推动合作共荣,借组内差异实现自治特色发展。三轨并进协同指引高等教育分类改革向纵深发展。 展开更多
关键词 高校分类改革 元主体协同 三三机制韧性 自主知识体系 分类共治
在线阅读 下载PDF
Predicting Stock Prices Using Polynomial Classifiers: The Case of Dubai Financial Market 被引量:4
12
作者 Khaled Assaleh Hazim El-Baz Saeed Al-Salkhadi 《Journal of Intelligent Learning Systems and Applications》 2011年第2期82-89,共8页
Predicting stock price movements is a challenging task for academicians and practitioners. In particular, forecasting price movements in emerging markets seems to be more elusive because they are usually more volatile... Predicting stock price movements is a challenging task for academicians and practitioners. In particular, forecasting price movements in emerging markets seems to be more elusive because they are usually more volatile often accompa-nied by thin trading-volumes and they are susceptible to more manipulation compared to mature markets. Technical analysis of stocks and commodities has become a science on its own;quantitative methods and techniques have been applied by many practitioners to forecast price movements. Lagging and sometimes leading technical indicators pro-vide rich quantitative tools for traders and investors in their attempt to gain advantage when making investment or trading decisions. Artificial Neural Networks (ANN) have been used widely in predicting stock prices because of their capability in capturing the non-linearity that often exists in price movements. Recently, Polynomial Classifiers (PC) have been applied to various recognition and classification application and showed favorable results in terms of recog-nition rates and computational complexity as compared to ANN. In this paper, we present two prediction models for predicting securities’ prices. The first model was developed using back propagation feed forward neural networks. The second model was developed using polynomial classifiers (PC), as a first time application for PC to be used in stock prices prediction. The inputs to both models were identical, and both models were trained and tested on the same data. The study was conducted on Dubai Financial Market as an emerging market and applied to two of the market’s leading stocks. In general, both models achieved very good results in terms of mean absolute error percentage. Both models show an average error around 1.5% predicting the next day price, an average error of 2.5% when predicting second day price, and an average error of 4% when predicted the third day price. 展开更多
关键词 DUBAI FINANCIAL MARKET POLYNOMIAL classifiers STOCK MARKET Neural Networks
暂未订购
Real and Altered Fingerprint Classification Based on Various Features and Classifiers 被引量:1
13
作者 Saif Saad Hameed Ismail Taha Ahmed Omar Munthir Al Okashi 《Computers, Materials & Continua》 SCIE EI 2023年第1期327-340,共14页
Biometric recognition refers to the identification of individuals through their unique behavioral features(e.g.,fingerprint,face,and iris).We need distinguishing characteristics to identify people,such as fingerprints... Biometric recognition refers to the identification of individuals through their unique behavioral features(e.g.,fingerprint,face,and iris).We need distinguishing characteristics to identify people,such as fingerprints,which are world-renowned as the most reliablemethod to identify people.The recognition of fingerprints has become a standard procedure in forensics,and different techniques are available for this purpose.Most current techniques lack interest in image enhancement and rely on high-dimensional features to generate classification models.Therefore,we proposed an effective fingerprint classification method for classifying the fingerprint image as authentic or altered since criminals and hackers routinely change their fingerprints to generate fake ones.In order to improve fingerprint classification accuracy,our proposed method used the most effective texture features and classifiers.Discriminant Analysis(DCA)and Gaussian Discriminant Analysis(GDA)are employed as classifiers,along with Histogram of Oriented Gradient(HOG)and Segmentation-based Feature Texture Analysis(SFTA)feature vectors as inputs.The performance of the classifiers is determined by assessing a range of feature sets,and the most accurate results are obtained.The proposed method is tested using a Sokoto Coventry Fingerprint Dataset(SOCOFing).The SOCOFing project includes 6,000 fingerprint images collected from 600 African people whose fingerprints were taken ten times.Three distinct degrees of obliteration,central rotation,and z-cut have been performed to obtain synthetically altered replicas of the genuine fingerprints.The proposal achieved massive success with a classification accuracy reaching 99%.The experimental results indicate that the proposed method for fingerprint classification is feasible and effective.The experiments also showed that the proposed SFTA-based GDA method outperformed state-of-art approaches in feature dimension and classification accuracy. 展开更多
关键词 Fingerprint classification HOG SFTA discriminant analysis(DCA)classifier gaussian discriminant analysis(GDA)classifier SOCOFing
在线阅读 下载PDF
Combination of classifiers with incomplete frames of discernment 被引量:1
14
作者 Zhunga LIU Jingfei DUAN +2 位作者 Linqing HUANG Jean DEZERT Yongqiang ZHAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第5期145-157,共13页
The methods for combining multiple classifiers based on belief functions require to work with a common and complete(closed)Frame of Discernment(Fo D)on which the belief functions are defined before making their combin... The methods for combining multiple classifiers based on belief functions require to work with a common and complete(closed)Frame of Discernment(Fo D)on which the belief functions are defined before making their combination.This theoretical requirement is however difficult to satisfy in practice because some abnormal(or unknown)objects that do not belong to any predefined class of the Fo D can appear in real classification applications.The classifiers learnt using different attributes information can provide complementary knowledge which is very useful for making the classification but they are usually based on different Fo Ds.In order to clearly identify the specific class of the abnormal objects,we propose a new method for combination of classifiers working with incomplete frames of discernment,named CCIF for short.This is a progressive detection method that select and add the detected abnormal objects to the training data set.Because one pattern can be considered as an abnormal object by one classifier and be committed to a specific class by another one,a weighted evidence combination method is proposed to fuse the classification results of multiple classifiers.This new method offers the advantage to make a refined classification of abnormal objects,and to improve the classification accuracy thanks to the complementarity of the classifiers.Some experimental results are given to validate the effectiveness of the proposed method using real data sets. 展开更多
关键词 Abnormal object Belief functions Classifier fusion Evidence theory DETECTION
原文传递
Video Concept Detection Based on Multiple Features and Classifiers Fusion 被引量:1
15
作者 Dong Yuan Zhang Jiwei +2 位作者 Zhao Nan Chang Xiaofu Liu Wei 《China Communications》 SCIE CSCD 2012年第8期105-121,共17页
The rapid growth of multimedia content necessitates powerful technologies to filter, classify, index and retrieve video documents more efficiently. However, the essential bottleneck of image and video analysis is the ... The rapid growth of multimedia content necessitates powerful technologies to filter, classify, index and retrieve video documents more efficiently. However, the essential bottleneck of image and video analysis is the problem of semantic gap that low level features extracted by computers always fail to coincide with high-level concepts interpreted by humans. In this paper, we present a generic scheme for the detection video semantic concepts based on multiple visual features machine learning. Various global and local low-level visual features are systelrtically investigated, and kernelbased learning method equips the concept detection system to explore the potential of these features. Then we combine the different features and sub-systen on both classifier-level and kernel-level fusion that contribute to a more robust system Our proposed system is tested on the TRECVID dataset. The resulted Mean Average Precision (MAP) score is rmch better than the benchmark perforrmnce, which proves that our concepts detection engine develops a generic model and perforrrs well on both object and scene type concepts. 展开更多
关键词 concept detection visual feature extraction kemel-based learning classifier fusion
在线阅读 下载PDF
Comparative Study on Tree Classifiers for Application to Condition Monitoring ofWind Turbine Blade through Histogram Features Using Vibration Signals: A Data-Mining Approach 被引量:1
16
作者 A.Joshuva V.Sugumaran 《Structural Durability & Health Monitoring》 EI 2019年第4期399-416,共18页
Wind energy is considered as a alternative renewable energy source due to its low operating cost when compared with other sources.The wind turbine is an essential system used to change kinetic energy into electrical e... Wind energy is considered as a alternative renewable energy source due to its low operating cost when compared with other sources.The wind turbine is an essential system used to change kinetic energy into electrical energy.Wind turbine blades,in particular,require a competitive condition inspection approach as it is a significant component of the wind turbine system that costs around 20-25 percent of the total turbine cost.The main objective of this study is to differentiate between various blade faults which affect the wind turbine blade under operating conditions using a machine learning approach through histogram features.In this study,blade bend,hub-blade loose connection,blade erosion,pitch angle twist,and blade cracks were simulated on the blade.This problem is formulated as a machine learning problem which consists of three phases,namely feature extraction,feature selection and feature classification.Histogram features are extracted from vibration signals and feature selection was carried out using the J48 decision tree algorithm.Feature classification was performed using 15 tree classifiers.The results of the machine learning classifiers were compared with respect to their accuracy percentage and a better model is suggested for real-time monitoring of a wind turbine blade. 展开更多
关键词 Condition monitoring fault diagnosis wind turbine blade machine learning histogram features tree classifiers
在线阅读 下载PDF
Modeling the effects of mechanical parameters on the hydrodynamic behavior of vertical current classifiers 被引量:3
17
作者 Arabzadeh Jarkani Soroush Khoshdast Hamid +1 位作者 Shariat Elaheh Sam Abbas 《International Journal of Mining Science and Technology》 SCIE EI 2014年第1期123-127,共5页
This study modeled the effects of structural and dimensional manipulations on hydrodynamic behavior of a bench vertical current classifier. Computational fluid dynamics (CFD) approach was used as modeling method, an... This study modeled the effects of structural and dimensional manipulations on hydrodynamic behavior of a bench vertical current classifier. Computational fluid dynamics (CFD) approach was used as modeling method, and turbulent intensity and fluid velocity were applied as system responses to predict the over- flow cut size variations. These investigations showed that cut size would decrease by increasing diameter and height of the separation column and cone section depth, due to the decrease of turbulent intensity and fluid velocity. As the size of discharge gate increases, the overflow cut-size would decrease due to freely fluid stream out of the column. The overflow cut-size was significantly increased in downward fed classifier compared to that fed by upward fluid stream. In addition, reforming the shape of angular overflow outlet's weir into the curved form prevented stream inside returning and consequently unselec- tire cut-size decreasing. 展开更多
关键词 Hydraulic classifier Modeling Computational fluid dynamic Cut size
在线阅读 下载PDF
WORD SENSE DISAMBIGUATION BASED ON IMPROVED BAYESIAN CLASSIFIERS 被引量:1
18
作者 Liu Ting Lu Zhimao Li Sheng 《Journal of Electronics(China)》 2006年第3期394-398,共5页
Word Sense Disambiguation (WSD) is to decide the sense of an ambiguous word on particular context. Most of current studies on WSD only use several ambiguous words as test samples, thus leads to some limitation in prac... Word Sense Disambiguation (WSD) is to decide the sense of an ambiguous word on particular context. Most of current studies on WSD only use several ambiguous words as test samples, thus leads to some limitation in practical application. In this paper, we perform WSD study based on large scale real-world corpus using two unsupervised learning algorithms based on ±n-improved Bayesian model and Dependency Grammar (DG)-improved Bayesian model. ±n-improved classifiers reduce the window size of context of ambiguous words with close-distance feature extraction method, and decrease the jamming of useless features, thus obviously improve the accuracy, reaching 83.18% (in open test). DG-improved classifier can more effectively conquer the noise effect existing in Naive-Bayesian classifier. Experimental results show that this approach does better on Chinese WSD, and the open test achieved an accuracy of 86.27%. 展开更多
关键词 Word Sense Disambiguation (WSD) Natural Language Processing (NLP) Unsupervised learning algorithm Dependency Grammar (DG) Bayesian classifier
在线阅读 下载PDF
Fault Detection of Fuel Injectors Based on One-Class Classifiers 被引量:1
19
作者 Dimitrios Moshou Athanasios Natsis +3 位作者 Dimitrios Kateris Xanthoula-Eirini Pantazi Ioannis Kalimanis Ioannis Gravalos 《Modern Mechanical Engineering》 2014年第1期19-27,共9页
Fuel injectors are considered as an important component of combustion engines. Operational weakness can possibly lead to the complete machine malfunction, decreasing reliability and leading to loss of production. To o... Fuel injectors are considered as an important component of combustion engines. Operational weakness can possibly lead to the complete machine malfunction, decreasing reliability and leading to loss of production. To overcome these circumstances, various condition monitoring techniques can be applied. The application of acoustic signals is common in the field of fault diagnosis of rotating machinery. Advanced signal processing is utilized for the construction of features that are specialized in detecting fuel injector faults. A performance comparison between novelty detection algorithms in the form of one-class classifiers is presented. The one-class classifiers that were tested included One-Class Support Vector Machine (OCSVM) and One-Class Self Organizing Map (OCSOM). The acoustic signals of fuel injectors in different operational conditions were processed for feature extraction. Features from all the signals were used as input to the one-class classifiers. The one-class classifiers were trained only with healthy fuel injector conditions and compared with new experimental data which belonged to different operational conditions that were not included in the training set so as to contribute to generalization. The results present the effectiveness of one-class classifiers for detecting faults in fuel injectors. 展开更多
关键词 Fuel Injectors FAULT Detection ACOUSTICS NEURAL Networks ONE-CLASS classifiers
暂未订购
Integrating RFID Technology with Intelligent Classifiers for Meaningful Prediction Knowledge 被引量:1
20
作者 Peter Darcy Steven Tucker Bela Stantic 《Advances in Internet of Things》 2013年第2期27-33,共7页
Radio Frequency Identification (RFID) is wireless technology that has been designed to automatically identify tagged objects using a reader. Several applications of this technology have been introduced in past literat... Radio Frequency Identification (RFID) is wireless technology that has been designed to automatically identify tagged objects using a reader. Several applications of this technology have been introduced in past literature such as pet identification and luggage tracking which have increased the efficiency and effectiveness of each environment into which it was integrated. However, due to the ambiguous nature of the captured information with the existence of missing, wrong and duplicate readings, the wide-scale adoption of the architecture is limited to commercial sectors where the integrity of the observations can tolerate ambiguity. In this work, we propose an application of RFID to take the reporting of class attendance and to integrate a predictive classifier to extract high level meaningful information that can be used in diverse areas such as scheduling and low student retention. We conclude by providing an analysis of the core strengths and opportunities that exist for this concept and how we might extend it in future research. 展开更多
关键词 RADIO Frequency Identification CLASSIFIER PREDICTION NEURAL NETWORK BAYESIAN NETWORK
暂未订购
上一页 1 2 250 下一页 到第
使用帮助 返回顶部