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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1645-1656页

作者： han Zheng Liming Fu Xinbo ji Ziyong Li Yanle sun Sixin Zhao Wei Wang Aidang Shan School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Central Research Institute(R&D Center) Baoshan Iron&Steel Co.LTDShanghaiChina

The evolution of ferrite grain and cementite lamella during cold rolling in a granular carbide–pearlite steel has been *** attention has been given to a quantitative characterization of changes in the ferrite *** backscattered diff raction and transmission electron microscopy observations show that the ultrafi ne ferrite(~388 nm)can be produced through low equivalent strain cold rolling without severe plastic deformation(SPD)and *** average grain size of ferrite depends on the volume fraction,shape and distribution of granular carbides as well as interlamellar spacing of pearlite.A general explanation of granular carbides-assisted grain refi nement is that the embedded carbides between natural barrier will signifi cantly facilitate dislocation nucleation during cold *** reaction occurs more drastically and quickly near these granular *** reactions promote the formation of high-angle grain *** formation of ultrafi ne ferrite grains and subgrains in steel after cold rolling toε=1.4 strain makes the strength and ductility increased simultaneously compared withε=0.6 cold-rolled *** results suggest a new material design strategy to obtain ultrafi ne-grained structure via the granular carbides assistance.

关键词： Grain refinement Carbide Pearlitic steel Cold rolling

Two new diterpenoids from Isodon serra

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Chinese Chemical Letters 2007年第11期18卷 1383-1385页

作者： Fu Lin Yan Lai Bin Zhang ji Xia Zhang han Dong sun Pharmacy College Xinxiang Medical University Xinxiang 453003 China Kunming Institute of Botuny Chinese Academy of Sciences Kunming 650204 China

From the aerial part of Isodon serra, two new ent-6,7-seco-kaurane-type diterpenoids, 15α,20β-dihydroxy-6β- methoxy-6,7- seco-6,20-epoxy-1,7-olide-ent-kaur-16-ene （1） and 6α,15α-dihydroxy-20-aldehyde-6,7-seco-6,11α-epoxy-1,7-olide-ent-kaur-16- ene （2） were isolated. Their structures were elucidated by spectroscopic means.

关键词： Labiatae Isodon serra ent-6,7-seco-Kaurane diterpenoid

Geometry and Hardy spaces on spaces of homogeneous type in the sense of Coifman and Weiss

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Science China Mathematics 2017年第11期60卷 2199-2218页

作者： han YanChang han YongSheng LI ji School of Mathematical Sciences South China Normal University Department of Mathematics Auburn University Department of Mathematics Macquarie University

It is known that the space of homogeneous type introduced by Coifman and Weiss(1971) provides a very natural setting for establishing a theory of Hardy spaces. This paper concentrates on how the geometrical conditions of the space of homogeneous type play a crucial role in building a theory of Hardy spaces via the Littlewood-Paley functions.

关键词： spaces of homogeneous type Hardy space singular integrals Carleson measure space BMO

COVID-19 Detection via a 6-Layer Deep Convolutional Neural Network

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Computer Modeling in Engineering & Sciences 2022年第2期130卷 855-869页

作者： Shouming Hou ji han School of Computer Science and Technology Henan Polytechnic UniversityJiaozuo454000China

Many people around the world have lost their lives due to *** symptoms of most COVID-19 patients are fever,tiredness and dry cough,and the disease can easily spread to those around *** the infected people can be detected early,this will help local authorities control the speed of the virus,and the infected can also be treated in *** proposed a six-layer convolutional neural network combined with max pooling,batch normalization and Adam algorithm to improve the detection effect of COVID-19 *** the 10-fold cross-validation methods,our method is superior to several state-of-the-art *** addition,we use Grad-CAM technology to realize heat map visualization to observe the process of model training and detection.

关键词： COVID-19 deep learning convolutional neural network max pooling batch normalization Adam Grad-CAM

基于多模态唇部状态识别的语音导航抗干扰系统

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江苏大学学报（自然科学版） 2025年第1期46卷 82-90页

作者：王晗陈怡霖季钰姣杜若琳南通大学信息科学技术学院江苏南通226019 南通大学交通与土木工程学院江苏南通226019

针对现有车载语音导航设备易受到车内外噪声干扰、无法准确判定声音信号来源的问题,提出了一种基于唇部状态识别的语音导航抗干扰系统.通过摄像头实时识别驾驶员唇部状态,准确判定驾驶员声音信号的起止时间端点,进而控制语音导航输入信... 详细信息

针对现有车载语音导航设备易受到车内外噪声干扰、无法准确判定声音信号来源的问题,提出了一种基于唇部状态识别的语音导航抗干扰系统.通过摄像头实时识别驾驶员唇部状态,准确判定驾驶员声音信号的起止时间端点,进而控制语音导航输入信号开启和关闭,增强驾驶员对语音导航的控制权限,减少车内外的噪声干扰.为保证唇部状态识别的准确性和鲁棒性,提出了一种基于关键点-外观短时特征融合的多模态唇部状态识别网络,进行了关键点短时特征有效性试验、多模态特征融合的唇部状态识别消融试验、实验室模拟环境和真实车载环境下的语音导航抗干扰试验.结果表明,文中提出的关键点短时特征算子可增强唇部状态变化表征能力14%以上,关键点-外观特征融合的唇部状态识别网络通过特征互补提升识别准确性8.98%以上.基于该网络的语音导航抗干扰系统准确性高(92.6%)、实时性好(检测速度为35帧/s);在驾驶员左、右侧面超过70°的大幅度头部姿态变化下,能有效减少车内外噪声对导航语音控制的干扰,表现出较高的鲁棒性.

关键词：语音导航抗干扰系统唇部状态识别关键点外观特征特征融合长短期记忆网络

Ultrathin Al2O3-coated reduced graphene oxide membrane for stable lithium metal anode

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Rare Metals 2018年第6期37卷 510-519页

作者： Fan Zhang Fei Shen ZhaoYang Fan Xin ji Bin Zhao ZhouTing sun YingYing Xuan XiaoGang han Center of Nanomaterials for Renewable Energy State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University Xi'an 710049 Shaanxi China Key Laboratory of Smart Grid of Shaanxi Province Xi'an 710049 Shaanxi China

Lithium （Li） metal has been considered as the most attractive anode materials for Li-ion batteries （LIBs） due to its high theoretic specific capacity. The formation of unstable solid electrolyte interphase （SEI） and dendritic Li on the metal anode, however, hindered its practical application. Herein, to address the issues, a Li-free electrode with ultrathin Al2O3 coated on reduced graphene oxide （rGO） membrane that covers a Cu foil current collector was developed. The composite electrode exhibits excellent interfacial protection of lithium metal deposited between Cu foil and rGO electrochemically. Firstly, it affords good Li^＋ permeability from the electrolyte. Secondly, the ultrathin Al2O3 has sufficient mechanical strength to inhibit the penetration of Li dendrite. Li metal was observed uniformly deposited between rGO membrane and Cu collector, and stable cycle performance of Li plating/stripping with Coulombic efficiency of ~ 91.75% at the lOOth cycle is achieved in organic carbonate electrolyte without any additives.

关键词： Lithium metal anode Atomic layer deposition rGO membrane Li-free anode Li protection

Fracture Toughness Properties of Three Different Biomaterials Measured by Nanoindentation

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Journal of Bionic Engineering 2007年第1期4卷 11-17页

作者： ji-yu sun jin Tong Key Laboratory of Terrain-Machine Bionics Engineering （Ministry of Education China） Jilin University （Nanling Campus） Changchun 130022 P. R. China

The fracture toughness of hard biomaterials, such as nacre, bovine hoof wall and beetle cuticle, is associated with fibrous or lamellar structures that deflect or stop growing cracks. Their hardness and reduced modulus were measured by using a nanoindenter in this paper. Micro/nanoscale cracks were generated by nanoindentation using a Berkovich tip. Nanoindentation of nacre and bovine hoof wall resulted in pile-up around the indent. It was found that the fracture toughness （Kc） of bovine hoof wall is the maximum, the second is nacre, and the elytra cuticle of dung beetle is the least one.

关键词： biomimetics bionics biomaterials nanoindentation laminated structure fracture toughness

Alternative industrial carbon emissions benchmark based on input-output analysis

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Frontiers of Earth Science 2016年第4期10卷 731-739页

作者： Mengyao han Xi ji Institute of Geographic Sciences and Natural Resources Research Chineses Academy of Sciences Beijing 100871 China College of Engineering Peking University Beijing 100871 China School of Economics Peking University Beijing 100871 China

Some problems exist in the current carbon emissions benchmark setting systems. The primary con- sideration for industrial carbon emissions standards highly relate to direct carbon emissions （power-related emissions） and only a portion of indirect emissions are considered in the current carbon emissions accounting processes. This practice is insufficient and may cause double counting to some extent due to mixed emission sources. To better integrate and quantify direct and indirect carbon emissions, an embodied industrial carbon emissions benchmark setting method is proposed to guide the establishment of carbon emissions benchmarks based on input-output analysis. This method attempts to link direct carbon emissions with inter-industrial economic exchanges and systematically quantifies carbon emissions embodied in total product delivery chains. The purpose of this study is to design a practical new set of embodied intensity-based benchmarks for both direct and indirect carbon emissions. Beijing, at the first level of carbon emissions trading pilot schemes in China, plays a significant role in the establish- ment of these schemes and is chosen as an example in this study. The newly proposed method tends to relate emissions directly to each responsibility in a practical way through the measurement of complex production and supply chains and reduce carbon emissions from their original sources. This method is expected to be developed under uncertain internal and external contexts and is further expected to be generalized to guide the establish- ment of industrial benchmarks for carbon emissions trading schemes in China and other countries.

关键词： emissions trading scheme benchmarking,carbon emissions input-output analysis

Electrochemical co-reduction of holmium and magnesium ions in eutectic LiCl-KCl salts

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Rare Metals 2022年第4期41卷 1394-1402页

作者： ji Wang Mei Li Wei han Zhi-Yixiong Liu Xiao-Guang Yang Yang sun Mi-Lin Zhang Key Laboratory of Superlight Materials and Surface Technology College of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China Institute of Nuclear Energy and Safety Harbin Engineering UniversityHarbin 150001China

The electrochemical co-reduction of Ho(Ⅲ)and Mg(Ⅱ)ions was investigated on Mo electrode in eutectic LiCl–KCl salts at temperature of 773 K using various electrochemical *** voltammogram(CV)and square wave voltammogram exhibit three reduction peaks corresponding to the reduction of Ho(Ⅲ)on pre-deposited Mg electrode,whose potentials are more positive than that of Ho on Mo electrode because of the formation of Mg-Ho intermetallic compounds by co-reduction of Ho(Ⅲ)and Mg(Ⅱ)***,chronopotentiometry and open-circuit chronopotentiometry were used to explore the electrochemical formation of Mg–Ho ***–Ho alloys were produced by galvanostatic electrolysis at the current of 1.5 A for different electrolysis ***_(5)Mg_(24),HoMg_(2) and HoMg intermetallic compounds were acquired and characterized by X-ray diffraction(XRD)and scanning electron microscopy(SEM)coupled with energy-dispersive spectroscopy(EDS).The results indicate that Mg–Ho intermetallic compounds,Ho_(5)Mg_(24),HoMg_(2) and HoMg,could be prepared by molten salts electrolysis.

关键词： Electrochemical formation Co-reduction MgHo alloys Galvanostatic electrolysis

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计算机视觉领域对抗样本检测综述

计算机科学 2025年第1期52卷 345-361页

作者：张鑫张晗牛曼宇姬莉霞郑州大学网络空间安全学院郑州450001 智能警务四川省重点实验室四川泸州646000 四川大学计算机学院成都610065

随着数据量的增加和硬件性能的提升,深度学习在计算机视觉领域取得了显著进展.然而,深度学习模型容易受到对抗样本的攻击,导致输出发生显著变化.对抗样本检测作为一种有效的防御手段,可以在不改变模型结构的前提下防止对抗样本对深度学... 详细信息

随着数据量的增加和硬件性能的提升,深度学习在计算机视觉领域取得了显著进展.然而,深度学习模型容易受到对抗样本的攻击,导致输出发生显著变化.对抗样本检测作为一种有效的防御手段,可以在不改变模型结构的前提下防止对抗样本对深度学习模型造成影响.首先,对近年来的对抗样本检测研究工作进行了整理,分析了对抗样本检测与训练数据的关系,根据检测方法所使用特征进行分类,系统全面地介绍了计算机视觉领域的对抗样本检测方法;然后,对一些结合跨领域技术的检测方法进行了详细介绍,统计了训练和评估检测方法的实验配置;最后,汇总了一些有望应用于对抗样本检测的技术,并对未来的研究挑战进行展望.

关键词：深度学习对抗样本攻击对抗样本检测人工智能安全图像分类