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基于对称网络的光学和SAR影像变化检测

遥感学报 2024年第6期28卷 1560-1575页

作者：汤玉奇林泽锋韩特杨欣邹滨冯徽徽中南大学有色金属成矿预测与地质环境监测教育部重点实验室长沙410083 中南大学地球科学与信息物理学院长沙410083

相比同源影像,光学影像和合成孔径雷达SAR(Synthetic Aperture Radar)影像变化检测具有充分利用不同类型数据之间的互补信息、发挥其各自优势的优点,已成为遥感领域的研究热点,在应急灾害监测等方面具有广阔的应用前景。然而,光学影像和... 详细信息

相比同源影像,光学影像和合成孔径雷达SAR(Synthetic Aperture Radar)影像变化检测具有充分利用不同类型数据之间的互补信息、发挥其各自优势的优点,已成为遥感领域的研究热点,在应急灾害监测等方面具有广阔的应用前景。然而,光学影像和SAR影像的成像特征差异导致无法直接对比双时相影像提取变化信息,现有光学影像和SAR影像变化检测方法对特征空间统一的精度与效率不高。对此,本文认为光学影像和SAR影像间的差异主要由成像特征差异导致,因此可以通过特征空间变换,将影像映射到同一特征空间进行比较。由此提出了一种新的对称网络结构,通过基于相似性度量的网络初始化及优化,将光学影像和SAR影像映射到近似的特征空间中进行比较并提取变化信息。首先度量对称网络提取的多组特征之间的相似性,利用相似性最大特征组对应的网络权重实现网络初始化,引导光学影像和SAR影像特征映射。然后通过相似性优化学习将光学影像和SAR影像映射到同一特征空间进行直接对比,并对多时相特征变化向量进行聚类分析以区分变化类型。本文利用3组光学影像和SAR影像数据集(Google Earth影像、Landsat 8影像和哨兵1号影像)的实验结果表明:相对于现有方法,本文方法的卡帕系数KC(Kappa Coefficient)至少提高了4.02%,且运行时间至少降低了30.79%,有效提高了光学影像和SAR影像变化检测的精度与效率。

关键词：遥感光学影像 SAR影像变化检测对称网络特征提取空间映射相似性度量变化类型

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基于不确定性感知网络的可信机械故障诊断

机械工程学报 2024年第12期60卷 194-206页

作者：邵海东肖一鸣邓乾旺任颖莹韩特湖南大学机械与运载工程学院长沙410082 盾构及掘进技术国家重点实验室郑州450001 清华大学工业工程系北京100084

基于深度学习的故障诊断方法受其黑箱特性限制难以给出可信赖和可解释的诊断结果。现有可解释故障诊断研究多集中在开发可解释模块并嵌入深度学习模型以赋予诊断结果一定物理意义,或以结果为基础反推模型做出此决策的深层逻辑,对于如何... 详细信息

基于深度学习的故障诊断方法受其黑箱特性限制难以给出可信赖和可解释的诊断结果。现有可解释故障诊断研究多集中在开发可解释模块并嵌入深度学习模型以赋予诊断结果一定物理意义,或以结果为基础反推模型做出此决策的深层逻辑,对于如何量化诊断结果中的不确定性并解释其来源和构成的研究工作十分有限。不确定性量化及分解不仅能提供诊断结果的可信度,还能辨析数据中未知因素的来源,最终指导提升诊断模型的可解释性。因此,提出将贝叶斯变分学习嵌入Transformer以开发一种不确定性感知网络,用于可信机械故障诊断。设计了一种变分注意力机制并定义了相应的优化目标函数,可建模注意力权重的先验分布和变分后验分布,从而赋予网络感知不确定性的能力。制定了一种不确定性量化及分解方案,可实现诊断结果的可信度表征以及认知不确定性和偶然不确定性的分离。以行星齿轮箱智能故障诊断为例,在测试数据中含有未知故障模式、未知噪声水平以及未知工况样本的分布外泛化场景中,充分验证了所提方法用于可信故障诊断的可行性。

关键词：可信故障诊断不确定性感知网络变分注意力不确定性量化及分解贝叶斯深度学习

Chiral mesostructured hematite with temperature-independent magnetism due to spin confinement

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Nano Research 2024年第3期17卷 2019-2024页

作者： Baiwen Zhang Jing Ai Yingying Duan te Bai Lu han Shunai Che School of Physics Science and Engineering Tongji UniversityShanghai 200092China School of Chemistry and Chemical Engineering Tongji UniversityShanghai 200092China Wuxi Vocational College of Science and technology Wuxi 214028China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

Hematite(α-Fe_(2)O_(3))is known to undergo conversion from weak ferromagnetic to antiferromagnetic as the temperature decreases below the Morin temperature(TM=250 K)due to spin moment rotation occurring during the Morin transition(MT).Herein,we endowed hematite with mesostructured chirality to maintain weak ferromagnetism without *** mesostructured hematite(CMH)nanoparticles were prepared by a hydrothermal method with glutamic acid(Glu)as the symmetry-breaking *** triangular bipyramidal CMH nanoparticles were composed of helically cleaved nanoflakes with twisted crystal ***-cooled(FC)magnetization measurements showed that the magnetic moments of CMH were stabilized without MT within the temperature range of 10–300 *** loop measurements confirmed the weak ferromagnetism of *** enhanced Dzyaloshinskii–Moriya interaction(DMI)was speculated to be responsible for the temperature-independent weak ferromagnetism,in which the spin configuration would be confined with canted antiferromagnetic coupling due to the mesostructured chirality of CMH.

关键词： hematite chiral mesostructure Dzyaloshinskii–Moriya interaction weak ferromagnetism antiferromagnetic material temperature-independent magnetism

水体重金属Pb、Cd污染的室内高光谱特征反演研究

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测绘与空间地理信息 2024年第2期47卷 104-108页

作者：罗智文汤玉奇邹滨冯徽徽韩特周石松中南大学地球科学与信息物理学院湖南长沙410083 有色金属成矿预测与地质环境监测教育部重点实验室(中南大学) 湖南长沙410083 时空信息与智能服务自然资源部重点实验室(中南大学) 湖南长沙410083

针对水体重金属污染水质参数复杂、重金属含量少导致的遥感监测光谱反射率低、特征响应波段不明显等问题,本文以铅(Pb)、镉(Cd)为研究对象,配制室内单一重金属多浓度污染标准溶液,在光谱数学变换的基础上,通过相关性分析获取水体重金属P... 详细信息

针对水体重金属污染水质参数复杂、重金属含量少导致的遥感监测光谱反射率低、特征响应波段不明显等问题,本文以铅(Pb)、镉(Cd)为研究对象,配制室内单一重金属多浓度污染标准溶液,在光谱数学变换的基础上,通过相关性分析获取水体重金属Pb、Cd的污染特征响应波段,并进一步构建单波段非线性及多波段偏最小二乘反演模型。所获水体重金属Pb、Cd污染特征响应波段上的光谱特征与对应标准溶液的重金属污染浓度的相关性分析及其模型反演精度表明:一阶微分与包络线去除可有效提高水体重金属污染特征波段提取精度,且多波段反演模型优于单波段模型。本文可为进一步开展野外水体重金属污染反演研究提供理论支撑。

关键词：水体重金属污染室内标样高光谱特征提取污染含量反演

Determination of multilevel chirality in nickel molybdate films by electron crystallography

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Nano Research 2024年第9期17卷 8571-8577页

作者： Jing Ai Yu Wang Liyuan Li Jianqiang Wang te Bai Shunai Che Lu han Sinopec(Shanghai)Research Institute of Petrochemical technology Co. Ltd.Shanghai 201208China School of Chemical Science and Engineering Tongji UniversityShanghai 200092China School of Chemistry and Chemical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240China

Chiral inorganic materials have attracted great attention owning to their unique physical and chemical properties attributed to the symmetry-breaking of their *** inorganic materials can be endowed with chiral geometric configurations from achiral space group crystals through lattice twisting,screw dislocations or hierarchical self-assembled spiral morphologies,showing various characteristic chiral ***,the multilevel chirality in chiral nickel molybdate films(CNMFs)remains to be elaborately *** this paper,we report three hierarchical levels of chirality in CNMFs,spanning from the atomic to the micron scale,including primary helically coiled nanoflakes with twisted atomic crystal lattices,secondary helical stacking of layered nanoflakes,and tertiary asymmetric morphology between adjacent *** findings may enrich the chiral self-assembly structural types and provide valuable insights for the comprehensive analysis path of hierarchical chiral crystals.

关键词： chiral inorganic material nickel molybdate structural analysis transmission electron microscopy electron crystallography

Efficacy and safety of electroacupuncture for insomnia:A systematic review and meta-analysis

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Journal of Integrative Medicine 2024年第4期22卷 459-472页

作者： han-yu Xu Lin-na Wu Yuan Zhang te Ba Xiao-feng Zhao Acupuncture and Moxibustion Department First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin 300193China National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Tianjin 300193China

Background:Electroacupuncture is often used to treat ***:To evaluate the efficacy and safety of electroacupuncture for *** strategy:Databases including PubMed,Cochrane Library,Embase,Web of Science,Chinese Biomedical Literature Database,China National Knowledge Infrastructure,Wanfang Data and VIP Fulltext e-Journals Database were searched up to January 15,*** criteria:Randomized clinical trials were included if they compared the clinical efficacy and safety of electroacupuncture with sham acupuncture,no treatment or usual care (UC) and general *** extraction and analysis:The full texts of the studies were reviewed to remove ineligible *** extracted data included authors,publication year,diagnostic criteria,sample size,population characteristics,interventions and *** above steps were performed independently by two reviewers and the data were cross ***15.0 software was used to analyze the extracted outcome *** continuous data (Pittsburgh Sleep Quality Index[PSQI]score and Insomnia Severity Index score),weighted mean difference (WMD) was calculated and 95% confidence interval (CI) was reported when the same scale was *** dichotomous variables (clinical response rate and adverse events),a meta-analysis was performed using risk ratio (RR) as the effect ***:Thirty-one trials with 2226 subjects were *** meta-analysis suggested that electroacupuncture was more effective in improving insomnia compared with the control group (sham acupuncture,no treatment,UC and general acupuncture)(RR=1.21;95 CI:[1.16,1.27]),significantly reducing the PSQI score in insomnia patients after treatment and at follow-up (WMD=-3.23;95%CI:[-4.29,-2.17];P<0.001).There was no significant difference in the incidence of adverse events between the EA and control groups (sham acupuncture and no treatment or ***=1.48;95%CI:[0.91,2.40];P=0.117).In addition,the regression results revealed t

关键词： Electroacupuncture Insomnia Systematic review Meta-analysis

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基于深度学习的工业装备PHM研究综述

振动．测试与诊断 2022年第5期42卷 835-847,1029页

作者：李彦夫韩特清华大学工业工程系北京100084

随着物联网和通信技术的快速发展,现代工业装备海量运行数据被实时监测传输,推动装备服役阶段的故障预测与健康管理进入大数据时代。面对具有不确定性强、价值密度低及多源异构特点的装备运行大数据,传统浅层模型算法存在难以自主挖掘... 详细信息

随着物联网和通信技术的快速发展,现代工业装备海量运行数据被实时监测传输,推动装备服役阶段的故障预测与健康管理进入大数据时代。面对具有不确定性强、价值密度低及多源异构特点的装备运行大数据,传统浅层模型算法存在难以自主挖掘数据蕴含特征、对装备健康状态表征能力弱的先天不足。近年来,作为机器学习领域的研究热点,深度学习理论得到了学术界与工业界的广泛关注,相关的工业装备故障预测与健康管理(prognostics and health management,简称PHM)研究与应用层出不穷,为解决大数据背景下的故障预测与健康管理难题提供了新的思路和技术手段。为此,笔者回顾了工业装备故障预测与健康管理技术发展历程;从异常检测、故障诊断以及故障预测3个方面综述了深度学习已取得的研究成果;讨论了深度学习在当下工业装备故障预测与健康管理中的热点话题;分析了该研究方向在工程实际中面临的挑战,并探讨应对这些挑战的有效措施和未来发展趋势。

关键词：工业装备深度学习故障诊断故障预测与健康管理

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A Dietary Supplement Jinghuosu Ameliorates Reproductive Damage Induced by Tripterygium Glycosides

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Chinese Journal of Integrative Medicine 2024年第4期30卷 330-338页

作者： MA Jing SUN Bo te Li-ger HUANG Xin ZUO Xin han Xiao-ke WANG Shu-song Hebei Key Laboratory of Reproductive Medicine Hebei Institute of Reproductive HealthHebei Reproductive Health HospitalShijiazhuang(050071)China Graduate School of Hebei Medical University Shijiazhuang(050017)China School of Chemistry and Materials Science Hebei Normal UniversityShijiazhuang(050024)China Xingtai Infertility Specialist Hospital XingtaiHebei Province(054000)China

Objective To determine the possible protective effects of Jinghuosu,a dietary supplement(DS),on tripterygium glycosides(TG)-induced reproductive system injury in rats and its underlying *** A reproductive damage model was established in rats by feeding of ***-eight male Sprague Dawley rats were randomly divided into 4 groups using a random number table(n=7 in each):control(C)group,model(M)group,DS group and L-carnitine(LC)*** in M,DS and LC groups received 40 mg/kg TGs *** from the 5th week,after administration of TGs for 4 h every day,rats in DS and LC groups were administered with 2.7 g/kg DS and 0.21 g/kg LC,respectively,for protective treatment over the next 4 *** in Group C continued to receive the control ***-eosin staining was used for histopathological analysis of rat testicular ***-linked immunosorbent assay was performed to measure alkaline phosphatase(ALP),lactate dehydrogenase,alcohol dehydrogenase,total antioxidant capacity(T-AOC),superoxide dismutase,glutathione peroxidase(GSH-Px),and malondialdehyde(MDA)*** assay was used to determine the serum testosterone *** real-time PCR and Western blotting were conducted to analyze the expression of genes and proteins related to the testosterone synthesis pathway and the nuclear factor erythroid 2-related factor 2/heme oxygenase 1 antioxidant *** Oral administration of TGs induced significant increases in the testicular levels of zinc transporter 1 and MDA(Phand,sperm concentration,sperm motility,and serum testosterone,serum zinc,testicular zinc,Zrt-,Irt-like protein 1,ALP,luteinizing hormone(LH)receptor,steroidogenic acute regulatory protein,Cytochrome P450 family 11 subfamily A member 1,3β-hydroxysteroid dehydrogenase 1 T-AOC,GSH-Px,nuclear factor erythroid 2-related factor 2,heme oxygenase-1 and NAD(P)H:quinone oxidoreductase 1 levels decreased following TG

关键词： dietary supplement Jinghuosu tripterygium glycosides reproductive damage infertility

A PDGFRβ-targeting nanodrill system for pancreatic fibrosis therapy

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Chinese Chemical Letters 2024年第10期35卷 353-359页

作者： han han Bi-te Chen Jia-Rong Ding Jin-Ming Si Tian-jiao Zhou Yi Wang Lei Xing Hu-Lin Jjiang State Key Laboratory of Natural Medicines Department of PharmaceuticsChina Pharmaceutical UniversityNanjing 210009China College of Pharmacy .Yanbian UniversityYanji 133002China Department of Nephrology Changhai HospitalNaval Medical UniversityShanghai 200433China

Activated pancreatic stellate cells(PSCs)are the main source of collagen layer deposition and the key target in pancreatic ***,no effective treatment specific to pancreatic fibrosis clinically,owing to the drug accumulation blocked by the collagen barrier and thus it is difficult to inhibit activated PSCs ***,a PSCs-targeting nano-system based on“nanodrill”strategy(LA-PC)was designed to enhance the accumulation of all-trans retinoic acid(ATRA)in PSCs,relying on the platelet-derived growth factor receptor beta(PDGFRβ)-targeting peptide(p PB:C*SRNLIDC*)and collagenase(Col).After being injected into fibrotic mice via tail vein,the Col modified on LA-PC can remove the excess collagen layer,and the drug delivery efficiency through pPB targeting peptide was more than 5 times higher than that of free ATRA,as well as the degree of fibrosis significantly ***,this nano-system effectively inhibited platelet-derived growth factor subunit B(PDGF-BB)/PDGFRβaxis on PSCs via a down-regulated extracellular signal-regulated protein kinase(ERK)pathway,and accordingly reduced the level of ***,the smart platform provided a promising strategy for the treatment of pancreatic fibrosis to achieve the precise regulation of PSCs.

关键词： Pancreatic fibrosis Pancreatic stellate cells Liposome PDGFRβ pPB peptide