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Parameterization and Application of Storm Surge/Tide Modeling Using a Genetic Algorithm for Typhoon Periods

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Advances in Atmospheric Sciences 2011年第5期28卷 1067-1076页

作者： Sung Hyup YOU Yong Hee lee Woo jeong lee Marine Meteorology Division Observation Infrastructure Bureau/KMA Korea Forecast Research Laboratory National Institute of Meteorological Research/KMA Korea Global Environment System Research Laboratory National Institute of Meteorological Research/KMA Korea

A genetic algorithm was used to optimize the parameters of the two-dimensional Storm Surge/Tide Operational Model （STORM） to improve sea level *** genetic algorithm was applied to nine typhoons that affected the Korean Peninsula during *** following model parameters were used：the bottom drag coefficient,the background horizontal diffusivity,Smagorinski＇s horizontal viscosity,and the sea level pressure ***,the simulation results using the optimized,mean,and median parameter values improved sea level *** four estimated parameters improved the sea level prediction by 76% and 54% in the bias and root mean square error for Typhoon Kalmaegi （0807） in 2008,***-month simulations of February and August 2008 were also improved using the estimated *** study demonstrates that parameter optimization on STORM can improve sea level prediction.

关键词： genetic algorithm STORM sea level typhoon

Risk of ischaemic stroke in patients with transient global amnesia: a propensity-matched cohort study

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Stroke & Vascular Neurology 2022年第2期7卷 101-107页

作者： Sang Hun lee Keon-Yeup Kim jeong-Woo lee So-jeong Park Jin-Man Jung Department of Neurology Korea University Ansan HospitalKorea University College of MedicineAnsanRepublic of Korea Data Science Team Hanmi Pharm.Co.LtdSeoulRepublic of Korea Korea University Zebrafish Translational Medical Research Center AnsanRepublic of Korea

Background The exact pathophysiological mechanism of transient global amnesia(TGA)is *** is debatable whether TGA is a risk factor for ***,here we investigated the possibility of TGA as a risk factor for stroke in a real-world setting using large-scale nationwide health claims *** We used health claims data from the Korean National Health Insurance Service(NHIS).Patients diagnosed with TGA between 2007 and 2013 were *** initially extracted patients without TGA who were preferentially matched for age and sex with the patients with TGA at a ratio of 10:1 from the whole ***,we performed 1:2 propensity score matching analysis to balance the baseline characteristics between the two *** the propensity score-matched dataset,we performed multivariable Cox regression analysis to investigate the association between TGA and stroke type,including ischaemic,haemorrhagic and all stroke *** Patients with TGA(n=14673)were selected from the NHIS *** extracting from the whole database(n=140486)and propensity score matching their data at a 1:2 ratio,a total of 10448 and 20442 patients were finally assigned to the TGA and control groups,*** multivariable Cox regression analysis demonstrated that the TGA group had a higher risk of ischaemic stroke and all types of stroke(adjusted HR=1.194;95%CI:1.043 to 1.368;and HR=1.197;95%CI:1.056 to 1.357,respectively).Conclusions Analysis of the nationwide claims database showed that TGA could be an important risk factor for stroke,especially for ischaemic stroke.

关键词： patients matched transient

Partial Oxidation of Methane with Sol-Gel Fe/Hf/YSZ Catalyst in Dielectric Barrier Discharge: Catalyst Activation by Plasma

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Journal of Rare Earths 2006年第5期24卷 513-518页

作者： Antonius Indarto Jae-Wook Choi Hwaung lee Hyung keun Song Jelliarko Palgunadi Clean Technology Research Center Korea Institute of Science and Technology KoreaDepartment of Chemical and Biological Engineering Korea University Korea Clean Technology Research Center Korea Institute of Science and Technology Korea Hydrogen Energy Research Center Korea Institute of Science and Technology Korea

A 1% Fe-30% Hf over yttria-stabilized zirconia catalyst in combination with novel plasma-assisted activation techniques for a direct partial oxidation of methane to methanol was tested using dielectric barrier discharge plasma at ambient temperature and atmospheric pressure. However, instead of methanol, the reaction products were dominated by HE, CO, CO2, C2, and H2O. A catalytically activated plasma process increased the production of methanol compared with a noncatalytic plasma process. The maximum selectivity of methanol production was achieved using a catalyst that was treated at higher applied power.

关键词： methane oxidation dielectric barrier discharge catalyst plasma activation rare earths

Acoustofluidic separation of prolate and spherical micro-objects

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Microsystems & Nanoengineering 2024年第1期10卷 217-230页

作者： Muhammad Soban Khan Mushtaq Ali Song Ha lee keun Young Jang Seong Jae lee Jinsoo Park Department of Mechanical Engineering Chonnam National University77 Yongbong-roBuk-guGwangju 61186Republic of Korea Department of Polymer Engineering The University of Suwon17 Wauan-gilBongdam-eupHwaseongGyeonggi 18323Republic of Korea

Most microfluidic separation techniques rely largely on object size as a separation *** ability to separate micro-objects based on their shape is crucial in various biomedical and chemical ***,we develop an ondemand,label-free acoustofluidic method to separate prolate ellipsoids from spherical microparticles based on traveling surface acoustic wave-induced acoustic radiation force and *** freely rotating non-spherical microobjects were aligned under the progressive acoustic field by the counterrotating radiation torque,and the major axis of the prolate ellipsoids was parallel to the progressive wave *** specific alignment of the ellipsoidal particles resulted in a reduction in the cross-sectional area perpendicular to the wave *** a consequence,the acoustic backscattering decreased,resulting in a decreased magnitude of the radiation *** the variation in radiation force,which depended on the micro-object morphology enabled the acoustofluidic shape-based *** conducted numerical simulations for the wave scattering of spherical and prolate objects to elucidate the working mechanism underlying the proposed method.A series of experiments with polystyrene microspheres,prolate ellipsoids,and peanut-shaped microparticles were performed for *** quantitative analysis of the separation efficiency,we confirmed the high purity and high recovery rate of the proposed acoustofluidic shapebased separation of *** a bioparticle,we utilize Thalassiosira eccentrica to perform shape-based separation,as the species has a variety of potential applications in drug delivery,biosensing,nanofabrication,bioencapsulation and immunoisolation.

关键词： separation spherical rotating

Effects of TiC on the microstructure refinement and mechanical property enhancement of additive manufactured Inconel 625/TiC metal matrix composites fabricated with novel core-shell composite powder

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Journal of Materials Science & Technology 2023年第33期164卷 13-26页

作者： Taegyu lee Wonjong jeong SeungHyeok Chung Ho Jin Ryu Department of Materials Science and Engineering Korea Advanced Institute of Science and TechnologyYu Seong-GuDae Hak-Ro 29134141 DaejeonRepublic of Korea Department of Nuclear and Quantum Engineering Korea Advanced Institute of Science and TechnologyYu Seong-GuDae Hak-Ro 29134141 DaejeonRepublic of Korea

The flexible product shape of additive manufacturing(AM)is attractive,but the process suffers from a lack of material property diversity due to a limited number of printable alloys and post-processing *** overcome this problem,the AM of metal matrix composites(MMCs)is a highly suitable solution because the properties of MMC can be tailored using various ***,extensive research has been conducted on the AM of MMCs;however,the major huddle for this process has been the difficulties in preparing feedstock powder and operating the AM *** study introduces an easily synthesizable core-shell composite powder,which was fabricated by a recently developed process called the SMART *** core-shell powder has a novel morphology,consisting of a metal core and composite shell,distinguishing it from the powders used in conventional AM *** 625/TiCp composites were fabricated using the core-shell composite powder,with various fractions of TiCp up to 10 vol.%.Compared to additive-manufactured Inconel 625,the additive-manufactured MMCs showed enhanced strength with significantly fewer *** results of this study may accelerate the application of MMC fabricated by AM,which offers superior properties and reliability compared to casting and powder metallurgy due to the higher degree of dislocation density and reinforcement dispersion.

关键词： Powder treatment Composite powder Metal matrix composite Additive manufacturing Nickel-based superalloy Directed energy deposition

Improved Photoresponse of UV Photodetectors by the Incorporation of Plasmonic Nanoparticles on Ga N Through the Resonant Coupling of Localized Surface Plasmon Resonance

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Nano-Micro Letters 2020年第7期12卷 175-190页

作者： Sundar Kunwar Sanchaya Pandit Jae-Hun jeong Jihoon lee Department of Electronic Engineering College of Electronics and InformationKwangwoon University

Very small metallic nanostructures,i.e.,plasmonic nanoparticles(NPs),can demonstrate the localized surface plasmon resonance(LSPR)e ect,a characteristic of the strong light absorption,scattering and localized electromagnetic field via the collective oscillation of surface electrons upon on the excitation by the incident *** LSPR of plasmonic NPs can significantly improve the photoresponse of the *** this work,significantly enhanced photoresponse of UV photodetectors is demonstrated by the incorporation of various plasmonic NPs in the detector *** size and elemental composition of monometallic Ag and Au NPs,as well as bimetallic alloy Ag Au NPs,are fabricated on Ga N(0001)by the solid-state dewetting *** photoresponse of various NPs are tailored based on the geometric and elemental evolution of NPs,resulting in the highly enhanced photoresponsivity of 112 A W-1,detectivity of 2.4×1012 Jones and external quantum e ciency of 3.6×104%with the high Ag percentage of Ag Au alloy NPs at a low bias of 0.1 *** Ag Au alloy NP detector also demonstrates a fast photoresponse with the relatively short rise and fall time of less than 160 and 630 ms,*** improved photoresponse with the Ag Au alloy NPs is correlated with the simultaneous e ect of strong plasmon absorption and scattering,increased injection of hot electrons into the Ga N conduction band and reduced barrier height at the alloy NPs/Ga N interface.

关键词： UV photodetection NP-based photodetectors Nanoparticles Plasmonic enhancement

Estimation of plasma density perturbation from dusty plasma injection by laser irradiation on tungsten target in DiPS

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Plasma Science and Technology 2020年第4期22卷 90-96页

作者： In Je KANG Min-keun BAE In Sun PARK Min Ji lee Kyu-Sun CHUNG Department of Electrical Engineering Hanyang UniversitySeoul 133791Republic of Korea Plasma Technology Research Center National Fusion Research InstituteGunsan 54004Republic of Korea

To investigate the interaction of dusty plasma with magnetized plasmas at divertor plasma simulator,radial profiles of plasma density(ne)and electron temperature were measured in terms of plasma discharge currents and magnetic flux intensity by using a fast scanning probes system with triple *** plasma with dusts(a generation rate of 3μg s-1 and a size of 1–10μm)was produced via interactions between a high-power laser beam and a full tungsten *** ne increases,the scale of the effects of dusty plasma injection on magnetized plasmas was ***,the duration of transient fluctuation was *** numerical estimation of plasma density perturbation due to dusty plasma injection,the result was 10%at a core region of the magnetized plasma with ne of(2–5)×10^11 cm^-3 at steady state condition.

关键词： plasma density perturbation dusty plasma tungsten dust DiPS

Remarks on Centers of Rings

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Algebra Colloquium 2021年第1期28卷 1-12页

作者： Juan Huang Hailan Jin Tai keun Kwak Yang lee Zhelin Piao Department of Mathematics Yanbian UniversityYanjiJilin 133002China Department of Mathematics Daejin UniversityPocheon 11159Korea Institute of Basic Science Daejin UniversityPocheon 11159Korea

It is proved that for matrices A,B in the n by n upper triangular matrix ring T_(n)(R)over a domain R,if AB is nonzero and central in T_(n)(R)then AB=*** n by n full matrix rings over right Noetherian domains are also shown to have this *** this article we treat a ring property that is a generalization of this result,and a ring with such a property is said to be weakly *** class of weakly reversible-over-center rings contains both full matrix rings over right Noetherian domains and upper triangular matrix rings over *** structure of various sorts of weakly reversible-over-center rings is studied in relation to the questions raised in the process *** also consider the connection between the property of being weakly reversible-over-center and the related ring properties.

关键词： weakly reversible-over-center ring center commutative domain right Noetherian domain reduced ring full(upper)triangular matrix ring NI ring

Nuclear symmetry energy from QCD sum rules

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Nuclear Science and Techniques 2013年第5期24卷 31-33页

作者： jeong Kie Sang lee Su Houng Institute of Physics and Applied Physics Yonsei University

We calculated the nucleon self-energies in iso-spin asymmetric nuclear matter and obtained the nuclear symmetry energy by taking difference of these of neutron and *** find that the scalar(vector) self-energy part gives a negative(positive) contribution to the nuclear symmetry energy,consistent with the result from relativistic mean-field ***,we found exact four-quark operator product expansion for nucleon sum *** them,twist-4 matrix elements which can be extracted from deep inelastic scattering experiment constitute an essential part in the origin of the nuclear symmetry energy from *** result also extends early success of QCD sum rule in the symmetric nuclear matter to the asymmetric nuclear matter.

关键词： QCD求和规则对称能非对称核物质相对论平均场理论核电矩阵元素散射实验对称性