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Chinese Physics B 2004年第6期13卷 789-793页

作者：周艳 K.w.whang J.H.yang D.C.Jeong C.H.Ha y.w.choi SchoolofOptoelectronicInformation UniversityofElectronicScienceandTechnologyofChinaChengdu610054China SchoolofElectricalEngineering SeoulNationalUniversitySan56-1Shinlim-dongKwanak-guSeoul151-742Korea KoreaElectrotechnologyResearchInstitute Changwon641-600Korea

The electric field in a surface discharge type ac-PDP cell with He or He/Xe(0.1%) mixture has been measured over a wide range of pressure (5–50 kPa) using laser induced fluorescence detection. The wall voltage was estimated from the measured electric field. The Stark manifolds of triplet atomic helium Rydberg state (2s3S) with principal quantum numbers (n=8 and 9) have been used to measure the electric field, as the lifetime of 2s3S is longer than the single atomic helium Rydberg state (2s1S) in high pressure discharge. Comparison of the Stark manifolds between the n=9 and n=8 shows that the measurement accuracy of electric field can be increased by 10%. The maximum electric field strength during discharge and the wall voltage at the end of pulse decreases with the increase of pressure. The comparison of He and He/Xe(0.1%) discharge at 13 kPa showed that He/Xe gas mixture discharge can accumulate more wall charge on MgO surface and the electric field was somewhat higher than those of pure helium discharge during pulse off period under the same discharge conditions.

关键词： plasma display panel laser induced fluorescence electric field measurement

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： S.w.wi y.S.Lee Department of Physics and Integrative Institute of Basic Sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu3+ GdNbO4 Codoping of Li+ Photoluminescence Sensitizer Rare earths

肺腺癌与表皮生长因子受体(EGFR)突变的放射基因相关性:成像特征与组织学亚型

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国际医学放射学杂志 2016年第6期 712-713页

作者： S.J.Hong T.J.Kim y.w.choi J.S.Park J.H.Chung K.w.Lee 王欣悦 Department of Radiology Seoul National University Bundang Hospital

摘要目的研究肺腺癌的影像特征与表皮生长因子受体(EGFR)突变和IASLC/ATS/ERS分类组织学亚型的联系。方法连续收集250例肺腺癌切除病例,研究表皮生长因子

关键词：表皮生长因子受体磨玻璃密度影像特征 EGFR 肺腺癌亚型相关性

Developmental impacts and toxicological hallmarks of silver nanoparticles across diverse biological models

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Environmental Science and Ecotechnology 2024年第3期19卷 60-79页

作者： yán wāng yapeng Han De-Xiang Xu Department of Toxicology School of Public Health&Key Laboratory of Environmental Toxicology of Anhui Higher Education InstitutesAnhui Medical UniversityHefei230032China

Silver nanoparticles(AgNPs),revered for their antimicrobial prowess,have become ubiquitous in a range of products,from biomedical equipment to food ***,amidst their rising popularity,concerns loom over their possible detrimental effects on fetal development and subsequent adult *** review delves into the developmental toxicity of AgNPs across diverse models,from aquatic species like zebrafish and catfish to mammalian rodents and in vitro embryonic stem *** focus encompasses the fate of AgNPs in different contexts,elucidating associated hazardous results such as embryotoxicity and adverse pregnancy ***,we scrutinize the enduring adverse impacts on offspring,spanning impaired neurobehavior function,reproductive disorders,cardiopulmonary lesions,and *** hallmarks of developmental harm are identified,encompassing redox imbalances,inflammatory cascades,DNA damage,and mitochondrial ***,we explore potential explanations,linking immunoregulatory dysfunction and disrupted epigenetic modifications to AgNPsinduced developmental *** substantial progress,our understanding of the developmental risks posed by AgNPs remains incomplete,underscoring the urgency of further research in this critical area.

关键词： Silver nanoparticles(AgNPs) Developmental toxicity Maternal exposure Fetal development Redox imbalance Mitochondrial dysfunction

Development of vehicle-recognition method on water surfaces using LiDAR data:SPD^(2)(spherically stratified point projection with diameter and distance)

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Defence Technology（防务技术） 2024年第6期36卷 95-104页

作者： Eon-ho Lee Hyeon Jun Jeon Jinwoo choi Hyun-Taek choi Sejin Lee The Department of Mechanical Engineering Kongju National University1223-24 Cheonan-daeroCheonan 31080Republic of Korea Ocean System Engineering Research Division Korea Research Institute of Ships and Ocean Engineering(KRISO)Daejeon 34103Republic of Korea The Division of Mechanical&Automotive Engineering Kongju National University1223-24 Cheonan-daeroCheonan 31080Republic of Korea

Swarm robot systems are an important application of autonomous unmanned surface vehicles on water *** monitoring natural environments and conducting security activities within a certain range using a surface vehicle,the swarm robot system is more efficient than the operation of a single object as the former can reduce cost and save *** is necessary to detect adjacent surface obstacles robustly to operate a cluster of unmanned surface *** this purpose,a LiDAR(light detection and ranging)sensor is used as it can simultaneously obtain 3D information for all directions,relatively robustly and accurately,irrespective of the surrounding environmental *** the GPS(global-positioning-system)error range exists,obtaining measurements of the surface-vessel position can still ensure stability during platoon *** this study,a three-layer convolutional neural network is applied to classify types of surface *** aim of this approach is to redefine the sparse 3D point cloud data as 2D image data with a connotative meaning and subsequently utilize this transformed data for object classification ***,we have proposed a descriptor that converts the 3D point cloud data into 2D image *** use this descriptor effectively,it is necessary to perform a clustering operation that separates the point clouds for each *** developed voxel-based clustering for the point cloud ***,using the descriptor,3D point cloud data can be converted into a 2D feature image,and the converted 2D image is provided as an input value to the *** intend to verify the validity of the proposed 3D point cloud feature descriptor by using experimental data in the ***,we explore the feasibility of real-time object classification within this framework.

关键词： Object classification Clustering 3D point cloud data LiDAR(light detection and ranging) Surface vehicle

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Synthetic brochosomes:Design,synthesis,and applications

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Nano Research 2024年第2期17卷 734-742页

作者： Lin wang Jinsol choi Tak-Sing wong Department of Mechanical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Biomedical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA

Brochosomes,which are nanoscopic buckyball-shaped granules produced by leafhoppers,are one of the most intricate structures discovered in *** functions of brochosomes have been proposed but only a few have been experimentally validated due to the challenge of fabricating their synthetic *** in micro-and nanofabrication have recently led to the emergence of synthetic brochosomes,opening up new possibilities for innovative *** review explores the early discovery of natural brochosomes and their geometrical features,followed by the recent progress in fabricating synthetic brochosomes and their *** on future applications and challenges in the scalable manufacturing of synthetic brochosomes are discussed.

关键词： synthetic brochosomes leafhopper antireflection superhydrophobicity surface-enhanced Raman scattering photocatalyst energy harvesting

Correlation between hydration properties and electrochemical performances on Ln cation size effect in layered perovskite for protonic ceramic fuel cells

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Journal of Energy Chemistry 2024年第1期88卷 1-9,I0001页

作者： Inhyeok Cho Jiwon yun Boseok Seong Junseok Kim Sun Hee choi Ho-Il Ji Sihyuk choi Department of Mechanical Engineering Kumoh National Institute of TechnologyGumi 39177GyeongbukRepublic of Korea Department of Aeronautics Mechanical and Electronic Convergence EngineeringKumoh National Institute of TechnologyGumi 39177GyeongbukRepublic of Korea Center for Energy Materials Research Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Center for Hydrogen and Fuel Cell Research Clean Technology Research DivisionKorea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Department of Energy and Environmental Engineering University of Science and TechnologySeoul 02792Republic of Korea Nanomaterials Science and Engineering Korea University of Science and Technology(UST)KIST CampusSeoul 02792Republic of Korea

PrBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(PrBSCF) has attracted much research interest as a potential triple ionic and electronic conductor(TIEC) electrode for protonic ceramic fuel cells(PCFCs). The chemical formula for Pr BSCF is AA'B_(2)O_(5+δ), with Pr(A-site) and Ba/Sr(A'-site) alternately stacked along the c-axis. Due to these structural features, the bulk oxygen ion diffusivity is significantly enhanced through the disorder-free channels in the PrO layer;thus, the A site cations(lanthanide ions) play a pivotal role in determining the overall electrochemical properties of layered perovskites. Consequently, previous research has predominantly focused on the electrical properties and oxygen bulk/surface kinetics of Ln cation effects,whereas the hydration properties for PCFC systems remain unidentified. Here, we thoroughly examined the proton uptake behavior and thermodynamic parameters for the hydration reaction to conclusively determine the changes in the electrochemical performances depending on LnBa_(0.5)Sr_(0.5)Co_(1.5)Fe_(0.5)O_(5+δ)(LnBSCF,Ln=Pr, Nd, and Gd) cathodes. At 500 ℃, the quantitative proton concentration of PrBSCF was 2.04 mol% and progressively decreased as the Ln cation size decreased. Similarly, the Gibbs free energy indicated that less energy was required for the formation of protonic defects in the order of Pr BSCF ween hydration properties and electrochemical performances in LnBSCF cathodes, PCFC single cell measurements and analysis of the distribution of relaxation time were further investigated.

关键词： Protonic ceramic fuel cell Cathode Triple ionic and electronic conductor Hydration property Proton uptake Gibbs free energy

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Learning feature alignment and dual correlation for few‐shot image classification

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CAAI Transactions on Intelligence Technology 2024年第2期9卷 303-318页

作者： Xilang Huang Seon Han choi Department of Electronic and Electrical Engineering Ewha Womans UniversitySeoulSouth Korea Graduate Program in Smart Factory Ewha Womans UniversitySeoulSouth Korea

Few‐shot image classification is the task of classifying novel classes using extremely limited labelled *** perform classification using the limited samples,one solution is to learn the feature alignment(FA)information between the labelled and unlabelled sample *** FA methods use the feature mean as the class prototype and calculate the correlation between prototype and unlabelled features to learn an alignment ***,mean prototypes tend to degenerate informative features because spatial features at the same position may not be equally important for the final classification,leading to inaccurate correlation ***,the authors propose an effective intraclass FA strategy that aggregates semantically similar spatial features from an adaptive reference prototype in low‐dimensional feature space to obtain an informative prototype feature map for precise correlation ***,a dual correlation module to learn the hard and soft correlations was developed by the *** module combines the correlation information between the prototype and unlabelled features in both the original and learnable feature spaces,aiming to produce a comprehensive cross‐correlation between the prototypes and unlabelled *** both FA and cross‐attention modules,our model can maintain informative class features and capture important shared features for *** results on three few‐shot classification benchmarks show that the proposed method outperformed related methods and resulted in a 3%performance boost in the 1‐shot setting by inserting the proposed module into the related methods.

关键词： image classification machine learning metric learning

Rapid monitoring of indoor airborne influenza and coronavirus with high air flowrate electrostatic sampling and PCR analysis

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 73-85页

作者： Sanggwon An Sangsoo choi Hyeong Rae Kim Jungho Hwang School of Mechanical Engineering Yonsei UniversitySeoul 02876Republic of Korea Gas Metrology Group Korea Research Institute of Standards and Science(KRISS)Daejeon 34113Republic of Korea

The world Health Organization has raised concerns about the possibility of airborne transmission in enclosed and poorly ventilated ***,rapid monitoring of airborne viruses is necessary in multi-use facilities with dense ***,an electrostatic air sampler(250 L/min)was developed in this work to obtain indoor viral aerosol samples for analysis via the Polymerase Chain Reaction(PCR).Aerosol tests with H1N1 and HCoV-229E were performed to evaluate the sample collection *** analysis,along with another aerosol test,was conducted to evaluate the recovery of the virus particles collected by the *** laboratory tests,our electrostatic sampler obtained viral samples that were detectable by PCR under the simulated viral pandemic scenario(3000 RNA copies per cubic meter of air)within 40 *** resulting cycle threshold(C)values were 35.07 and 37.1 for H1N1 and HCoV-229E,*** the performance evaluation in the laboratory,field tests were conducted in a university classroom from October 28 to December 2,*** A and HCoV-229E were detected in two air samples,and the corresponding C,values were 35.3 and *** PCR results are similar to those obtained from laboratory tests,considering the simulatedviralpandemic scenario.

关键词： Airborne virus Electrostatic sampler Rapid monitoring Indoor environment Field test

weakly Supervised Object Localization with Background Suppression Erasing for Art Authentication and Copyright Protection

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Machine Intelligence Research 2024年第1期21卷 89-103页

作者： Chaojie wu Mingyang Li ying Gao Xinyan Xie wing w.y.Ng Ahmad Musyafa School of Computer Science and Engineering South China University of TechnologyGuangzhou 511442China Guangdong Provincial Key Laboratory of Artificial Intelligence in Medical Image Analysis and Application Guangdong Provincial People's HospitalGuangzhou 510180China

The problem of art forgery and infringement is becoming increasingly prominent,since diverse self-media contents with all kinds of art pieces are released on the Internet every *** art paintings,object detection and localization provide an efficient and ef-fective means of art authentication and copyright ***,the acquisition of a precise detector requires large amounts of ex-pensive pixel-level *** alleviate this,we propose a novel weakly supervised object localization(wSOL)with background su-perposition erasing(BSE),which recognizes objects with inexpensive image-level ***,integrated adversarial erasing(IAE)for vanilla convolutional neural network(CNN)dropouts the most discriminative region by leveraging high-level semantic ***,a background suppression module(BSM)limits the activation area of the IAE to the object region through a self-guidance ***,in the inference phase,we utilize the refined importance map(RIM)of middle features to obtain class-agnostic loc-alization *** experiments are conducted on paintings,CUB-200-2011 and ILSVRC to validate the effectiveness of our BSE.

关键词： weakly supervised object localization erasing method deep learning computer vision art authentication and copyright protection