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Advances in Atmospheric Sciences 2005年第2期22卷 230-237页

作者： jae-jin kim Jong-jin BAIK Climate Environment System Research Center Seoul National University Seoul 151-742 KoreaSchool of Earth and Environmental Sciences Seoul National University Seoul 151-742 Korea

The effects of street bottom heating and inflow turbulence on urbanstreet-canyon flow are experimentally investigated using a circulating water channel. Threeexperiments are carried out for a street canyon with a street aspect ratio of 1. Results from eachexperiment with bottom heating or inflow turbulence are compared with those without bottom heatingand appreciable inflow turbulence. It is demonstrated that street bottom heating or inflowturbulence increases the intensity of the canyon vortex. A possible explanation on how street bottomheating or inflow turbulence intensifies the canyon vortex is given from a fluid dynamicalviewpoint.

关键词： urban street-canyon flow street bottom heating inflow turbulence circulating water channel

Effects of a Building’s Density on Flow in Urban Areas

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Advances in Atmospheric Sciences 2009年第1期26卷 45-56页

作者： jae-jin kim Do-Yong kim Department of Environmental Atmospheric Sciences Pukyong National University Busan Korea Center for Atmosphere Science and Earthquake Research Korea Meteorological Administration Busan Korea

The effects of a building＇s density on urban flows are investigated using a CFD model with the RNG k - ε turbulence closure scheme. Twenty-seven cases with different building＇s density parameters （e.g., building and street-canyon aspect ratios） are numerically simulated. As the building＇s density parameters vary, different flow regimes appear. When the street canyon is relatively narrow and high, two counterrotating vortices in the vertical direction are generated. The wind speed along streets is mainly affected by the building＇s length. However, it is very difficult to find or generalize the characteristics of the street-canyon flows in terms of a single building＇s density parameter. This is because the complicated flow patterns appear due to the variation of the vortex structure and vortex number. Volume-averaged vorticity magnitude is a very good indicator to reflect the flow characteristics despite the strong dependency of flows on the variation of the building＇s density parameters. Multi-linear regression shows that the volume-averaged vorticity magnitude is a strong function of the building＇s length and the street-canyon width. The increase in the building＇s length decreases the vorticity of the street-canyon flow, while, the increase in the street- canyon width increases the vorticity.

关键词： urban flow characteristics building's density parameter volume-averaged vorticity CFD model

Effects of Street-Bottom and Building-Roof Heating on Flow in Three-Dimensional Street Canyons

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Advances in Atmospheric Sciences 2010年第3期27卷 513-527页

作者： jae-jin kim Jong-jin BAIK Department of Environmental Atmospheric Sciences Pukyong National University School of Earth and Environmental Sciences Seoul National University

Using a computational fluid dynamics （CFD） model, the effects of street-bottom and building-roof heating on flow in three-dimensional street canyons are investigated. The building and street-canyon aspect ratios are one. In the presence of street-bottom heating, as the street-bottom heating intensity increases, the mean kinetic energy increases in the spanwise street canyon formed by the upwind and downwind buildings but decreases in the lower region of the streamwise street canyon. The increase in momentum due to buoyancy force intensifies mechanically induced flow in the spanwise street canyon. The vorticity in the spanwise street canyon strengthens. The temperature increase is not large because relatively cold above-roof-level air comes into the spanwise street canyon. In the presence of both street-bottom and building-roof heating, the mean kinetic energy rather decreases in the spanwise street canyon. This is caused by the decrease in horizontal flow speed at the roof level, which results in the weakening of the mean flow circulation in the spanwise street canyon. It is found that the vorticity in the spanwise street canyon weakens. The temperature increase is relatively large compared with that in the street-bottom heating case, because relatively warm above-roof-level air comes into the spanwise street canyon.

关键词： street canyon flow CFD model street-bottom heating building-roof heating mean kineticenergy vorticity

Boosted Lithium-Ion Transport Kinetics in n-Type Siloxene Anodes Enabled by Selective Nucleophilic Substitution of Phosphorus

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Nano-Micro Letters 2024年第10期16卷 618-637页

作者： Se In kim Woong-Ju kim jin Gu Kang Dong-Wan kim School of Civil Environmental and Architectural EngineeringKorea University02841 SeoulSouth Korea Nanophotonics Research Center Korea Institute of Science and Technology02792 SeoulSouth Korea

Doped two-dimensional(2D)materials hold significant promise for advancing many technologies,such as microelectronics,optoelectronics,and energy ***,n-type 2D oxidized Si nanosheets,namely n-type siloxene(n-SX),are employed as Li-ion battery *** thermal evaporation of sodium hypophosphite at 275℃,P atoms are effectively incorporated into siloxene(SX)without compromising its 2D layered morphology and unique Kautsky-type crystal ***,selective nucleophilic substitution occurs,with only Si atoms being replaced by P atoms in the O_(3)≡Si-H *** resulting n-SX possesses two delocalized electrons arising from the presence of two electron donor types:(i)P atoms residing in Si sites and(ii)H *** doping concentrations are varied by controlling the amount of precursors or their mean free *** at 2000 mA g^(-1),the n-SX electrode with the optimized doping concentration(6.7×10^(19) atoms cm^(-3))delivers a capacity of 594 mAh g^(-1) with a 73%capacity retention after 500 *** improvements originate from the enhanced kinetics of charge transport processes,including electronic conduction,charge transfer,and solid-state *** approach proposed herein offers an unprecedented route for engineering SX anodes to boost Li-ion storage.

关键词： Li-ion battery Two-dimensional N-type siloxene Doping mechanism Kinetics

Varifocal occlusion in an optical see-through near-eye display with a single phase-only liquid crystal on silicon

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Photonics Research 2024年第4期12卷 833-853页

作者： WOONGSEOB HAN jae-WON LEE JUNG-YEOP SHIN MYEONG-HO CHOI HAK-RIN kim jae-HYEUNG PARK Department of Electrical and Computer Engineering Inha University100 Inha-roMichuhol-guIncheon 22212Republic of Korea School of Electronic and Electrical Engineering Kyungpook National University80 Daehak-roBuk-guDaegu 41566Republic of Korea School of Electronics Engineering Kyungpook National University80 Daehak-roBuk-guDaegu 41566Republic of Korea Department of Information and Communication Engineering Inha University100 Inha-roMichuhol-guIncheon 22212Republic of Korea

We propose a near-eye display optics system that supports three-dimensional mutual *** exploiting the polarization-control properties of a phase-only liquid crystal on silicon (LCoS),we achieve real see-through scene masking as well as virtual digital scene imaging using a single *** depth control of the real scene mask and virtual digital image is also achieved by using a focus tunable lens (FTL) pair of opposite *** proposed configuration using a single LCoS and opposite curvature FTL pair enables the self-alignment of the mask and image at an arbitrary depth without distorting the see-through view of the real *** verified the feasibility of the proposed optics using two optical benchtop setups:one with two off-the-shelf FTLs for continuous depth control,and the other with a single Pancharatnam–Berry phase-type FTL for the improved form factor.

关键词： optics crystal phase

Modification strategies improving the electrochemical and structural stability of high-Ni cathode materials

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Journal of Energy Chemistry 2024年第9期96卷 185-205页

作者： Yoon Bo Sim Hami Lee Junyoung Mun Ki jae kim Department of Energy Science Sungkyunkwan UniversitySuwon 16419Republic of Korea School of Advanced Materials Sciencend Engineering Sungkyunkwan UniversitySuwon 16419Republic of Korea SKKU Institute of Energy Sciencend Technology(SIEST) Sungkyunkwan UniversitySuwon 16419Republic of Korea

With the increasing spotlight in electric vehicles,there is a growing demand for high-energy-density batteries to enhance driving ***,several studies have been conducted on high-energy-density LiNi_(x)Co_(y)Mn_(z)O_(2)***,there is a limit to permanent performance deterioration because of side reactions caused by moisture in the atmosphere and continuous microcracks during cycling as the Ni content to express high energy increases and the content of Mn and Co that maintain structural and electrochemical stabilization *** direct modification of the surface and bulk regions aims to enhance the capacity and long-term performance of high-Ni cathode ***,an efficient modification requires a study based on a thorough understanding of the degradation mechanisms in the surface and bulk *** this review,a comprehensive analysis of various modifications,including doping,coating,concentration gradient,and single crystals,is conducted to solve degradation issues along with an analysis of the overall degradation mechanism occurring in high-Ni cathode *** also summarizes recent research developments related to the following modifications,aims to provide notable points and directions for post-studies,and provides valuable references for the commercialization of stable high-energy-density cathode materials.

关键词： High energy density High-Ni cathode materials Degradation Structural stability Lithium-ion battery

Comparative efficacy and optimal duration of first-line antibiotic regimens for acute otitis media in children and adolescents:a systematic review and network meta-analysis of 89 randomized clinicaltrials

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World Journal of Pediatrics 2024年第3期20卷 219-229页

作者： Min Seo kim jae Han kim Seohyun Ryu Seung Won Lee Dong Keon Yon Eunyoung kim Ai Koyanagi Elena Dragioti jae Il Shin Lee Smith Samsung Advanced Institute forHealth Sciences&Technology(SAIHST) Samsung Medical CenterSungkyunkwan UniversitySeoulRepublic of Korea Yonsei University Collegeof Medicine SeoulRepublicof Korea Department of Precision Medicine Sungkyunkwan University School of MedicineSuwonRepublic of Korea Center for Digital Health Medical Science Research InstituteKyung Hee University College of MedicineSeoulRepublic of Korea Evidence-Based Research Laboratory Department of Clinical Pharmacy and Pharmaceutical CareCollege of PharmacyChung-Ang UniversitySeoulRepublic of Korea Parc Sanitari Sant Joan de Deu/CIBERSAM/ISCIII Universitat de BarcelonaFundacio Sant Joan de Déu.Sant Boi de LlobregatBarcelonaSpain ICREA Pg.Lluis Companys 23BarcelonaSpain Pain and Rehabilitation Centre and Department of Medical and Health SciencesLinkoping University58185 LinkopingSweden Department of Pediatrics Yonsei University College of MedicineYonsei-ro 50Seodaemun-gu8044Seoul 03722Republic of Korea Centre for Health Performanceand WellbeingAnglia Ruskin UniversityCambridge CB11PTUK Research Laboratory Psychology of Patients Families&Health ProfessionalsDepartment of NursingSchool of Health SciencesUniversity of IoanninaIoannina 45500Greece

Introduction Antibiotic use for acute otitis media(AOM)is one of the major sources of antimicrobial ***,the effective minimal antibiotic duration for AOM remains ***,guidelines often recommend broad ranges(5-10 days)of antibiotic use,yet the clinical impact of such a wide window has not been *** We systematically searched PubMed/MEDLINE,Embase,Scopus,Web of Science,and Cochrane Library from database inception to 6 October *** meta-analysis was conducted on randomized controlled trials that assessed antibiotic treatment for AOM in children(PROSPERO CRD42020196107).Results For amoxicillin and amoxicillin-clavulanate,7-day regimens were noninferior to 10-day regimens in clinical responses[amoxicillin:risk ratio(RR)0.919(95%CI 0.820-1.031),amoxicillin-clavulanate:RR 1.108(0.957-1.282)],except for≤2 *** the third-generation cephalosporins,7-day and 10-day regimens had similar clinical responses compared to placebo[7-day:RR 1.420(1.190-1.694),10-day:RR 1.238(1.125-1.362)compared to placebo].However,5-day regimens of amoxicillin-clavulanate and third-generation cephalosporins were inferior to 10-day *** to amoxicillin,a shorter treatment duration was tolerable with *** Our findings indicated that 1O days of antibiotic use may be unnecessarily long,while the treatment duration should be longer than 5 ***,5-day regimens would be sufficient for a modest treatment *** findings revealed that the current wide range of recommended antibiotic durations may have influenced the clinical outcome of AOM,and a narrower antibiotic duration window should be re-established.

关键词： Amoxicillin-potassium Amoxicillin Antibacterial agents Cephalosporins Duration of therapy

A pipeline to characterize p53 effectors by integrative cistrome and transcriptome analysis in a genetically-defined organoid model

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Genes & Diseases 2024年第2期11卷 512-515页

作者： June-Ha Shin Hwa-Ryeon kim jae-Seok Roe Department of Biochemistry College of Life Science and BiotechnologyYonsei UniversitySeoul 120-749Republic of Korea

Tumor-protein 53(p53)is a transcription factor(TF)encoded by TP53(Trp53 in mice)and is a master regulator of tumor-suppressive programs'.Importantly,TP53 is the most frequently mutated gene in human cancer,and its loss of function contributes to tumor development,exemplified by variable p53 mutations detected in 50%-75%of pancreatic cancers.2 From these perceptions,a number of targets transcribed by p53 that confer tumor suppression have been ***,our understanding of how p53 prevents normal cells from initiating tumorigenesis is still *** complement this limitation,herein,we established a new approach to identify underlying effectors transcribed by p53 in normal physiology.

关键词： incomplete initiating herein

Advances in Wireless,Batteryless,Implantable Electronics for Real‑Time,Continuous Physiological Monitoring

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Nano-Micro Letters 2024年第3期16卷 254-302页

作者： Hyeonseok kim Bruno Rigo Gabriella Wong Yoon jae Lee Woon‑Hong Yeo IEN Center for Wearable Intelligent Systems and Healthcare Georgia Institute of TechnologyAtlantaGA 30332USA George W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA School of Electrical and Computer Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Wallace H.Coulter Department of Biomedical Engineering Georgia Tech and Emory University School of MedicineAtlantaGA 30332USA Parker H.Petit Institute for Bioengineering and Biosciences Institute for MaterialsInstitute for Robotics and Intelligent MachinesGeorgia Institute of TechnologyAtlantaGA 30332USA

This review summarizes recent progress in developing wireless,batteryless,fully implantable biomedical devices for real-time continuous physiological signal monitoring,focusing on advancing human health *** considerations,such as biological constraints,energy sourcing,and wireless communication,are discussed in achieving the desired performance of the devices and enhanced interface with human *** addition,we review the recent achievements in materials used for developing implantable systems,emphasizing their importance in achieving multi-functionalities,biocompatibility,and *** wireless,batteryless devices offer minimally invasive device insertion to the body,enabling portable health monitoring and advanced disease ***,we summarize the most recent practical applications of advanced implantable devices for human health care,highlighting their potential for immediate commercialization and clinical uses.

关键词： Implantable electronics Biomedical systems Batteryless devices Wireless electronics Physiological signal monitoring

Ag-GST/HfO_(x)-based unidirectional threshold switching selector with low leakage current and threshold voltage distribution for high-density cross-point arrays

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Rare Metals 2024年第1期43卷 280-288页

作者： Kyoung-Joung Yoo Dae-Yun Kang Nahyun kim Ho-jin Lee Ta-Hyeong kim Taeho kim Tae Geun kim School of Electrical Engineering Korea UniversitySeoul 02841Republic of Korea

The use of electrochemical-metallization-based volatile threshold switching selectors in cross-point arrays has been widely explored owing to their high on-off ratios and simple ***,these devices are unsuitable for cross-point architectures because of the difficulty in controlling the random filament formation that results in large fluctuations in the threshold voltage during *** this study,we investigated the unidirectional threshold transition characteristics associated with an Ag/GST/HfO_(x)/Pt-based bilayer selector and demonstrated the occurrence of a low leakage current(<1×10^(-11) A) and low distribution of the threshold voltage(Δ0.11 V).The bilayer structure could control the filament formation in the intermediate state through the insertion of an HfO_(x) tunneling *** stacking a bilayer selector with NiO_(x)based resistive random-access memory,the leakage and programming currents of the device could be significantly *** the crossbar array configuration,we performed equivalent circuit analysis of a one-selector oneresistor(1S1R) devices and estimated the optimal array size to demonstrate the applicability of the proposed *** maximum acceptable crossbar array size of the 1S1R device with the Ag/GST/HfO_(x)/Pt/Ti/NiO_(x)/Pt structure was 5.29×10^(14)(N^(2),N=2.3×10^(7)).

关键词： Selector device Tunneling barrier Threshold switching Sputtering 1S1R Cross-point array