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一种直推式多标记文档分类方法

计算机研究与发展 2008年第11期45卷 1817-1823页

作者：姜远佘俏俏黎铭周志华南京大学计算机软件新技术国家重点实验室南京210093

真实世界的文档往往同时属于多个类别,因此,利用多标记学习技术进行文档分类是一个重要的研究方向.现有多标记文档分类方法需要利用大量有正确分类标记的文档才能获得好的分类性能,然而,在实际应用中往往只能得到少量的有标记文档作为... 详细信息

真实世界的文档往往同时属于多个类别,因此,利用多标记学习技术进行文档分类是一个重要的研究方向.现有多标记文档分类方法需要利用大量有正确分类标记的文档才能获得好的分类性能,然而,在实际应用中往往只能得到少量的有标记文档作为分类所需的训练文档.出于利用未标记文档的想法,提出一种基于随机游走的直推式多标记文档分类方法,可以利用大量的未标记文档来辅助提高分类性能.实验结果表明,该方法的性能优于现有直推式多标记分类方法CNMF.

关键词：文档分类多标记学习直推学习未标记文档随机游走

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大数据哈希学习:现状与趋势

科学通报 2015年第5期60卷 485-490页

作者：李武军周志华南京大学计算机软件新技术国家重点实验室南京210023 软件新技术与产业化协同创新中心南京210023

随着信息技术的迅速发展,各行各业积累的数据都呈现出爆炸式增长趋势,我们已经进入大数据时代.大数据在很多领域都具有广阔的应用前景,已经成为国家重要的战略资源,对大数据的存储、管理和分析也已经成为学术界和工业界高度关注的热点.... 详细信息

随着信息技术的迅速发展,各行各业积累的数据都呈现出爆炸式增长趋势,我们已经进入大数据时代.大数据在很多领域都具有广阔的应用前景,已经成为国家重要的战略资源,对大数据的存储、管理和分析也已经成为学术界和工业界高度关注的热点.收集、存储、传输、处理大数据的目的是为了利用大数据,而要有效地利用大数据,机器学习技术必不可少.因此,大数据机器学习(简称大数据学习)是大数据研究的关键内容之一.哈希学习通过将数据表示成二进制码的形式,不仅能显著减少数据的存储和通信开销,还能降低数据维度,从而显著提高大数据学习系统的效率.因此,哈希学习近年来成为大数据学习中的一个研究热点.本文对这方面的工作进行介绍.

关键词：大数据机器学习哈希学习大数据学习

THE STUDIES OF MALIGNANT TRANSFORMATION OF HUMAN EPITHELIAL CELLS INDUCED BY DIETHYL-NITROSAMINE (NDEA) IN VITRO

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中国科学B辑(英文版) 1986年第11期29卷 1186-1191页

作者：黄明王秀琴王志华周传农吴旻 Cancer Institute Chinese Academy of Medical Sciences Beijing Beijing

This is the first report on the diethylnitrosamine-induced malignant transformaton of hu-man epithelial cells derived from fetal kidney. The transformed cells have prolonged life span and aneuploid karyotypes. They also form anchorage independent colonies in soft agar. With additional one or two NDEA treatments, those cells could elicit poorly differontiated carcinomas in immunosuppressed new-born rats. This experiment indicates that the human fetal kidney cells seem to be a good material for studying the mechanisms of carcinogenesis of human epithelial cell.

关键词： carcinogenesis fetal anchorage carcinomas poorly prolonged IN VITRO NDEA transformed elicit

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一种针对弱标记的直推式多标记分类方法

计算机研究与发展 2010年第8期47卷 1392-1399页

作者：孔祥南黎铭姜远周志华南京大学计算机软件新技术国家重点实验室南京210093

多标记学习主要解决一个样本可以同时属于多个类别的问题,它广泛适用于图像场景分类、文本分类等任务.在传统的多标记学习中,分类器往往需要利用大量具有完整标记的训练样本才能获得较好的分类性能,然而,在很多现实应用中又往往只能获... 详细信息

多标记学习主要解决一个样本可以同时属于多个类别的问题,它广泛适用于图像场景分类、文本分类等任务.在传统的多标记学习中,分类器往往需要利用大量具有完整标记的训练样本才能获得较好的分类性能,然而,在很多现实应用中又往往只能获得少量标记不完整的训练样本.为了更好地利用这些弱标记训练样本,提出一种针对弱标记的直推式多标记分类方法,它可以通过标记误差加权来补全样本标记,同时也能更好地利用弱标记样本提高分类性能.实验结果表明,该方法在弱标记情况下的图像场景分类任务上具有较好的性能提高.

关键词：机器学习多标记学习弱标记图像场景分类直推式学习

SiO_(2) Induces Iron Overload and Ferroptosis in Cardiomyocytes in a Silicosis Mouse Model

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Biomedical and Environmental Sciences 2024年第6期37卷 617-627页

作者： Yongheng Wang Ning Li Yi Guan Tong LI Yuxiu Zhang Hong Cao zhihua Yu Zhiheng Li Shuoyan Li Jiahao Hu Wenxin zhou Sisi Qin Shuang Li Sanqiao Yao School of Public Health North China University of Science and TechnologyTangshan 063210HebeiChina Hebei Key Laboratory of Occupational Health and Safety for Coal Industry North China University of Science and TechnologyTangshan 063210HebeiChina Occupational Disease Prevention and Control Institute of Jinneng Holding Coal Industry Group Co. LtdDatong 037001ShanxiChina China Pingmei Shenma Group Occupational Disease Prevention and Control Hospital Pingdingshan 467000HenanChina School of Public Health Xinxiang Medical UniversityXinxiang 453003HenanChina

Objective The aim of this study was to explore the role and mechanism of ferroptosis in SiO_(2)-induced cardiac injury using a mouse *** Male C57BL/6 mice were intratracheally instilled with SiO_(2) to create a silicosis ***-1(Fer-1)and deferoxamine(DFO)were used to suppress *** biomarkers,oxidative stress markers,histopathology,iron content,and the expression of ferroptosis-related proteins were *** SiO_(2) altered serum cardiac injury biomarkers,oxidative stress,iron accumulation,and ferroptosis markers in myocardial ***-1 and DFO reduced lipid peroxidation and iron overload,and alleviated SiO_(2)-induced mitochondrial damage and myocardial ***_(2) inhibited Nuclear factor erythroid 2-related factor 2(Nrf2)and its downstream antioxidant genes,while Fer-1 more potently reactivated Nrf2 compared to *** Iron overload-induced ferroptosis contributes to SiO_(2)-induced cardiac *** ferroptosis by reducing iron accumulation or inhibiting lipid peroxidation protects against SiO_(2) cardiotoxicity,potentially via modulation of the Nrf2 pathway.

关键词： SiO_(2) exposure Iron overload Ferroptosis Cardiac injury Nrf2

Self-supervised recalibration network for person re-identification

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Defence Technology（防务技术） 2024年第1期31卷 163-178页

作者： Shaoqi Hou Zhiming Wang zhihua Dong Ye Li Zhiguo Wang Guangqiang Yin Xinzhong Wang Shenzhen Institute of Information Technology Shenzhen518172China University of Electronic Science and Technology of China Chengdu611731China Kash Institute of Electronics and Information Industry Kashi844099China

The attention mechanism can extract salient features in images,which has been proved to be effective in improving the performance of person re-identification(Re-ID).However,most of the existing attention modules have the following two shortcomings:On the one hand,they mostly use global average pooling to generate context descriptors,without highlighting the guiding role of salient information on descriptor generation,resulting in insufficient ability of the final generated attention mask representation;On the other hand,the design of most attention modules is complicated,which greatly increases the computational cost of the *** solve these problems,this paper proposes an attention module called self-supervised recalibration(SR)block,which introduces both global and local information through adaptive weighted fusion to generate a more refined attention *** particular,a special"Squeeze-Excitation"(SE)unit is designed in the SR block to further process the generated intermediate masks,both for nonlinearizations of the features and for constraint of the resulting computation by controlling the number of ***,we combine the most commonly used Res Net-50 to construct the instantiation model of the SR block,and verify its effectiveness on multiple Re-ID datasets,especially the mean Average Precision(m AP)on the Occluded-Duke dataset exceeds the state-of-the-art(SOTA)algorithm by 4.49%.

关键词： Person re-identification Attention mechanism Global information Local information Adaptive weighted fusion

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一种基于正则化的半监督多标记学习方法

计算机研究与发展 2012年第6期49卷 1272-1278页

作者：李宇峰黄圣君周志华计算机软件新技术国家重点实验室(南京大学) 南京210093

多标记学习主要用于解决单个样本同时属于多个类别的问题.传统的多标记学习通常假设训练数据集含有大量有标记的训练样本.然而在许多实际问题中,大量训练样本中通常只有少量有标记的训练样本.为了更好地利用丰富的未标记训练样本以提高... 详细信息

多标记学习主要用于解决单个样本同时属于多个类别的问题.传统的多标记学习通常假设训练数据集含有大量有标记的训练样本.然而在许多实际问题中,大量训练样本中通常只有少量有标记的训练样本.为了更好地利用丰富的未标记训练样本以提高分类性能,提出了一种基于正则化的归纳式半监督多标记学习方法——MASS.具体而言,MASS首先在最小化经验风险的基础上,引入两种正则项分别用于约束分类器的复杂度及要求相似样本拥有相似结构化多标记输出,然后通过交替优化技术给出快速解法.在网页分类和基因功能分析问题上的实验结果验证了MASS方法的有效性.

关键词：机器学习多标记学习半监督学习网页分类基因功能分析

Study on cumulative effects of biological craniocerebral trauma under repeated blast

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Theoretical & Applied Mechanics Letters 2024年第3期14卷 174-183页

作者： Xingyuan Huang Bingchen Xia Lijun Chang Zhikang Liao Hui Zhao zhihua Cai Hunan Provincial Key Laboratory of Health Maintenance for Mechanical Equipment Hunan University of Science and TechnologyXiangtan 411201China School of Mechanical and Electrical Engineering Foshan UniversityFoshan 528231China Institute for Traffic Medicine PLA Army Characteristic Medical CenterChongqing 400042China

Repeated blast impacts on personnel in explosive environments can exacerbate craniocerebral *** existing studies focus on the injury effects of a single blast,lacking in-depth analysis on the injury effects and cumulative effects of repeated ***,rats were used as the experimental samples to suffer from explosion blasts with different peak air overpressures(167 kPa~482 kPa)and varying number of repeated *** cumulative effect of craniocerebral trauma was most pronounced for moderate repeated blast,showing approximately 95%increase of trauma severity with penta blast,and an approximately 85%increase of trauma severity with penta minor *** cumulative effect of craniocerebral trauma from severe,repeated blast has a smaller rate of change compared to the other two *** severity of trauma from penta blast increased by approximately 69%compared to a single *** physiological,pathological and biochemical analysis show that the degree of neurological trauma caused by repeated blasts is higher than that of single blasts,and the pathological trauma to brain tissue is more extensive and *** trauma degree remains unchanged after double blast,increases by one grade after triple or quadruple blast,and increases by two grades after penta blast.

关键词： Repeated blast Craniocerebral trauma Trauma severity grade Cumulative effects

Current progress of research on heat -resistant Mg alloys: A review

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1406-1425页

作者： Hong Yang Wenlong Xie Jiangfeng Song zhihua Dong Yuyang Gao Bin Jiang Fusheng Pan National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

With the increasing attention received by lightweight metals,numerous essential fields have increased requirements for mag-nesium(Mg)alloys with good room-temperature and high-temperature mechanical ***,the high-temperature mechanic-al properties of commonly used commercial Mg alloys,such as AZ91D,deteriorate considerably with increasing *** the past several decades,extensive efforts have been devoted to developing heat-resistant Mg *** approaches either inhibit the gen-eration of thermally unstable phases or promote the formation of thermally stable precipitates/phases in matrices through solid solution or precipitation *** this review,numerous studies are systematically introduced and *** alloy systems,includ-ing those based on Mg–Al,Mg–Zn,and Mg–rare earth,are carefully classified and compared to reveal their mechanical properties and strengthening *** emphasis,limitations,and future prospects of these heat-resistant Mg alloys are also pointed out and dis-cussed to develop heat-resistant Mg alloys and broaden their potential application areas in the future.

关键词： magnesium alloys mechanical properties heat resistance microstructures high temperatures strengthening mechanisms