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| WoS | SCOPUS | Document Type | Document Title | Abstract | Authors | Affiliation | ResearcherID (WoS) | AuthorsID (SCOPUS) | Author Email(s) | Journal Name | JCR Abbreviation | ISSN | eISSN | Volume | Issue | WoS Edition | WoS Category | JCR Year | IF | JCR (%) | FWCI | FWCI Update Date | WoS Citation | SCOPUS Citation | Keywords (WoS) | KeywordsPlus (WoS) | Keywords (SCOPUS) | KeywordsPlus (SCOPUS) | Language | Publication Stage | Publication Year | Publication Date | DOI | JCR Link | DOI Link | WOS Link | SCOPUS Link |
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| ○ | ○ | Review | Manufacturing and potential applications of lattice structures in thermal systems: A comprehensive review of recent advances | Lattice structures are a class of cellular materials with enhanced thermomechanical properties compared with their counterpart cellular materials such as foams. They have recently attracted researchers towards implementation in various engineering applications due to their diverse fabrication techniques driven by the advancement in additive manufacturing technology. This article reviews the four classes of materials (polymers, ceramics, liquid resins, and metals and alloys) used to fabricate the various lattice structures employed in different thermal applications. Firstly, the classification and description of the lattice struc-tures are concluded, along with their applications in several domains in general and particularly in ther-mal systems. Secondly, the materials and fabrication techniques used for lattice structure manufacturing are briefly reviewed. Thirdly, extensive literature analysis is carried out on the heat transfer character-istics of numerous categories of lattice structures. Results revealed that lattice structures are the most promising media to enhance the thermo-hydraulic performance of heat-transferring systems in terms of augmenting the heat transfer rate and reducing the pressure drop. Meanwhile, some of its designs in-crease its thermal resistance, suitable for application in energy storage systems. On the basis of critical analysis of the fabrication, characterization and applications, several important conclusions are presented, along with the future research directions, to fill the gap in this area of research.(c) 2022 Elsevier Ltd. All rights reserved. | Sajjad, Uzair; Rehman, Tauseef-ur; Ali, Mubasher; Park, Cheol Woo; Yan, Wei-Mon | Natl Taipei Univ Technol, Dept Energy & Refrigerating Air Conditioning Engn, Taipei 10608, Taiwan; Natl Taipei Univ Technol, Res Ctr Energy Conservat New Generat Residential C, Taipei 10608, Taiwan; Kyungpook Natl Univ, Sch Mech Engn, Daegu 41566, South Korea; Chinese Univ Hong Kong, Dept Mech & Automat Engn, Hong Kong, Peoples R China | Rehman, Tauseef-ur/AAE-3086-2022; Ali, Mubasher/ISB-8509-2023; Sajjad, Uzair/AAV-8645-2021 | 57202950663; 57159403400; 57221004199; 7408416474; 57200197835 | chwoopark@knu.ac.kr;wmyan1234@gmail.com; | INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER | INT J HEAT MASS TRAN | 0017-9310 | 1879-2189 | 198 | SCIE | ENGINEERING, MECHANICAL;MECHANICS;THERMODYNAMICS | 2022 | 5.2 | 12.0 | 2.91 | 2025-06-25 | 90 | 95 | Lattice structures; Additive manufacturing; Heat transfer; Optimization; Pressure drop | HEAT-TRANSFER CHARACTERISTICS; NEGATIVE POISSONS RATIO; OPEN-CELL FOAMS; MECHANICAL-PROPERTIES; FLUID-FLOW; TOPOLOGY OPTIMIZATION; TRANSFER ENHANCEMENT; FORCED-CONVECTION; SURFACE-ROUGHNESS; ENERGY-ABSORPTION | Additive manufacturing; Heat transfer; Lattice structures; Optimization; Pressure drop | English | 2022 | 2022-12-01 | 10.1016/j.ijheatmasstransfer.2022.123352 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | |||
| ○ | ○ | Article | Reacting flow characteristics based on the axis-switching phenomenon in a baffled micro combustor with rotated noncircular holes for micro-thermophotovoltaic system | For a thermophotovoltaic (TPV) generator, a combustor design for strengthening the axis-switching phenomenon is explored. Various simulations based on a Reynolds stress model and detailed chemical mechanism of GRI 3.0 are performed for methane (CH4)-air flames in a multihole baffled combustor. The reacting flow fields are investigated with the baffle plates of rotated square and triangular holes. The spreading and merging of multiple air jets past the baffle plate are significantly affected by rotating noncircular air holes. Considering the crossover location changes of the jet half-width, the air jets have a flow structure that quickly generates the axis-switching phenomenon. Compared with the baffled combustor of circular air holes, the center recirculation zone in the combustor of noncircular holes is enlarged by approximately 200% with a hole rotation. As the hole rotation increases, secondary flows become more complicated and the merging of air jets is quickly finished. Based on these flow structures, the region with the stoichiometric condition is observed in various forms of hexagonal, star, circular, and flower shapes. As a result, the flammable region and combustion efficiency are considerably increased. The flame lengths are roughly evaluated as three times the mixing lengths. From the viewpoint of a heat emitter for the TPV application, the heat transfer on the combustion chamber wall is discussed. Compared with the combustor with circular air holes, the combustor with noncircular air holes shows a 5% increase in flammable region and a 5.9% improvement in combustion efficiency. For a combustion-based TPV system, the best uniformity of wall temperature is observed for baffles with 30 degrees-rotated square holes and 15 degrees rotated triangular holes and the highest mean wall temperatures are obtained when the flame length is approximately 1/3 of the combustor length. (C) 2022 Elsevier Ltd. All rights reserved. | Kim, Won Hyun; Park, Tae Seon | Kyungpook Natl Univ, Sch Mech Engn, 80 Daehak Ro, Daegu 41566, South Korea | 55360608000; 7401801892 | tsparkjp@knu.ac.kr; | INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER | INT J HEAT MASS TRAN | 0017-9310 | 1879-2189 | 195 | SCIE | ENGINEERING, MECHANICAL;MECHANICS;THERMODYNAMICS | 2022 | 5.2 | 12.0 | 1.34 | 2025-06-25 | 14 | 14 | Baffled micro combustor; Axis-switching phenomenon; Noncircular hole; Efficient combustion; Thermophotovoltaic system; Recirculating flow | SCALAR; JET | Axis-switching phenomenon; Baffled micro combustor; Efficient combustion; Noncircular hole; Recirculating flow; Thermophotovoltaic system | Combustors; Efficiency; Flow fields; Flow structure; Heat transfer; Jets; Merging; Plates (structural components); Rotation; Switching; Vortex flow; Air jet; Axis-switching; Axis-switching phenomenon; Baffled micro combustor; Efficient combustions; Micro combustor; Noncircular hole; Recirculating flow; Switching phenomenon; Thermophotovoltaic systems; Reynolds number | English | 2022 | 2022-10 | 10.1016/j.ijheatmasstransfer.2022.123169 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | |||
| ○ | ○ | Article | Thermal efficiency of eco-friendly MXene based nanofluid for performance enhancement of a pin-fin heat sink: Experimental and numerical analyses | MXenes are an eco-friendly innovative type of graphene-like nanomaterials and are proven to exhibit remarkable thermal, electrical, mechanical and optical properties. This study is aimed at evaluating the thermal efficiency of novel Ti(3)C(2)Tx MXene-based nanofluid in a pin-fin heat sink was via experimental and numerical analyses. The aqueous-based 2D Ti(3)C(2)Tx MXene nanofluid was synthesised in a twostep process, followed by their characterisation and experimental testing. For the numerical analysis, the forced convection of the nanofluid was simulated through multiphase Lagrangian-Eulerian approximation by incorporating the interphase interactions of Brownian motion, thermophoresis, drag and Saffman lift forces, gravity, virtual mass and pressure gradient-induced forces. The thermal performance of the MXene nanofluids was assessed in terms of log mean temperature difference, average Nusselt number, local temperature and local Nusselt number distribution at the base of the heat sink and thermal contours. Their fluid flow characteristics were probed by analysing the coolant pumping power, flow streamlines distribution and performance evaluation criteria of the heat sink. Results demonstrated that utilising the MXene-based coolant resulted in a significant average Nusselt number enhancement at the expense of a small increase in coolant pumping power. Maximum improvements of 29.8 and 40.5% in the average Nusselt number were observed for nanoparticle concentrations of 0.013 vol% and 0.027 vol% respectively. (c) 2021 Elsevier Ltd. All rights reserved. | Ambreen, Tehmina; Saleem, Arslan; Park, Cheol Woo | Kyungpook Natl Univ, Sch Mech Engn, 80 Daehakro, Daegu 41566, South Korea | ; Saleem, Arslan/ABA-5982-2021 | 57195420431; 57194776354; 7408416474 | chwoopark@knu.ac.kr; | INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER | INT J HEAT MASS TRAN | 0017-9310 | 1879-2189 | 186 | SCIE | ENGINEERING, MECHANICAL;MECHANICS;THERMODYNAMICS | 2022 | 5.2 | 12.0 | 4.22 | 2025-06-25 | 41 | 46 | Ti(3)C(2)Tx MXene; Pin-fin heat sink; Nanofluid; Heat transfer; Pressure drop; Performance evaluation criteria | HYBRID NANOFLUIDS; MICRO; CONDUCTIVITY; OPTIMIZATION; SHAPE; FLOW | Heat transfer; Nanofluid; Performance evaluation criteria; Pin-fin heat sink; Pressure drop; Ti<sub>3</sub>C<sub>2</sub>Tx MXene | Brownian movement; Coolants; Efficiency; Environmental protection; Fins (heat exchange); Flow of fluids; Gravitation; Numerical analysis; Nusselt number; Optical properties; Coolant pumping power; Eco-friendly; Experimental and numerical analysis; Graphene likes; Nanofluids; Performance enhancements; Performance evaluation criteria; Pin fin heat sinks; Thermal-efficiency; Ti3C2tx mxene; Nanofluidics | English | 2022 | 2022-05-01 | 10.1016/j.ijheatmasstransfer.2021.122451 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | Anticancer effects of veratramine via the phosphatidylinositol-3-kinase/serine-threonine kinase/mechanistic target of rapamycin and its downstream signaling pathways in human glioblastoma cell lines | Aims: Antitumor effects of veratramine in prostate and liver cancers has been investigated, but it is still unclear whether veratramine can be used as an effective therapeutic agent for glioma. The aim of this study was to evaluate the potential pharmacological mechanism of veratramine in glioma. Main methods: Using four types of human glioblastoma cell lines, including A172, HS-683, T98G, and U-373-MG the dose-dependent antitumor effect of veratramine was evaluated. The cytotoxicity and cell proliferation were examined by CCK-8, and cell proliferation was further confirmed by anchorage-independent colony formation assay. The cell cycle distribution and apoptotic rate was assessed by flow cytometry, and apoptosis was further evaluated by apoptosis assay. The migration and invasiveness capacity were analyzed by using transwell. Protein and mRNA levels of related factors were determined by western blotting and RT-qPCR, respectively. Key findings: Veratramine markedly induced apoptosis, suppressed the cell proliferation via the cell cycle G0/G1 phase arrest, and reduced the capacity for the migration and invasion in human glioblastoma multiforme cell lines. Moreover, veratramine was sufficient to affect the phosphatidylinositol-3-kinase/serine-threonine kinase/ mechanistic target of rapamycin signaling pathway and its downstream Mdm2/p53/p21 pathway in human glioblastoma cell lines. Significance: Antitumor effects of veratramine in suppression of glioma progression was mediated by the regulation of PI3K/Akt/mTOR and Mdm2/p53/p21 signaling pathway. | Kim, Daehwan; Kwon, Wookbong; Park, Song; Kim, Wansoo; Park, Jin-Kyu; Han, Jee Eun; Cho, Gil-Jae; Yun, Sungho; Han, Se-Hyeon; Kim, Myoung Ok; Ryoo, Zae Young; Choi, Seong-Kyoon | DGIST, Core Prot Resources Ctr, Daegu, South Korea; DGIST, Div Biotechnol, Daegu, South Korea; Kyungpook Natl Univ, BK21 FOUR KNU Creat Biores, Sch Life Sci, Daegu, South Korea; DGIST, Dept Brain & Cognit Sci, Daegu, South Korea; Kyungpook Natl Univ, Coll Vet Med, Daegu 41566, South Korea; SBS Seoul Broadcasting Syst, Dept News Team, Mokdongseo Ro 161, Seoul, South Korea; Hanyang Univ, Sch Media Commun, Wangsimni Ro 222, Seoul, South Korea; Kyungpook Natl Univ, ITRD, Dept Anim Sci & Biotechnol, Sangju 37224, South Korea | RYOO, ZAEYOUNG/AAQ-1573-2020 | 57212363780; 57139843600; 57139047900; 57352897900; 35213723500; 57214671240; 7201438083; 57201366734; 57210915063; 8934745900; 16937104900; 55505432500 | jaewoong64@knu.ac.kr;cskbest@dgist.ac.kr; | LIFE SCIENCES | LIFE SCI | 0024-3205 | 1879-0631 | 288 | SCIE | MEDICINE, RESEARCH & EXPERIMENTAL;PHARMACOLOGY & PHARMACY | 2022 | 6.1 | 12.1 | 1.14 | 2025-06-25 | 8 | 9 | Glioma; Veratramine; Human glioblastoma cell line; Sonic hedgehog; PI3K; Akt; mTOR; Mdm2; p53; p21 | MALIGNANT GLIOMA-CELLS; HEDGEHOG PATHWAY; PI3K/AKT/MTOR PATHWAY; ANTITUMOR-ACTIVITY; P53; INHIBITION; GROWTH; APOPTOSIS; VERATRUM; MEDULLOBLASTOMA | Glioma; Human glioblastoma cell line; Mdm2/p53/p21; PI3K/Akt/mTOR; Sonic hedgehog; Veratramine | Apoptosis; Biomarkers, Tumor; Cell Cycle; Cell Movement; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p21; Gene Expression Regulation, Neoplastic; Glioblastoma; Humans; Neoplasm Invasiveness; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-mdm2; TOR Serine-Threonine Kinases; Tumor Cells, Cultured; Tumor Suppressor Protein p53; Veratrum Alkaloids; ab 142376; antineoplastic agent; cholecystokinin octapeptide; mammalian target of rapamycin; mouse double minute 2 homolog; phosphatidylinositol 3 kinase; protein p21; protein p53; protein serine threonine kinase; sonic hedgehog protein; unclassified drug; veratramine; AKT1 protein, human; CDKN1A protein, human; cyclin dependent kinase inhibitor 1A; MDM2 protein, human; mouse double minute 2 homolog; MTOR protein, human; phosphatidylinositol 3 kinase; protein kinase B; protein p53; target of rapamycin kinase; TP53 protein, human; tumor marker; veratramine; Veratrum alkaloid; A-172 cell line; Akt signaling; antineoplastic activity; apoptosis; apoptosis assay; apoptosis rate; Article; cell cycle; cell cycle arrest; cell migration; cell proliferation; colony formation; controlled study; cytotoxicity; flow cytometry; G0 phase cell cycle checkpoint; G1 phase cell cycle checkpoint; glioblastoma cell line; glioma; Hs 683 cell line; human; human cell; reverse transcription polymerase chain reaction; signal transduction; T98G cell line; transwell assay; tumor invasion; U 373 Mg cell line; Western blotting; cell motion; drug effect; gene expression regulation; genetics; glioblastoma; metabolism; pathology; tumor cell culture | English | 2022 | 2022-01-01 | 10.1016/j.lfs.2021.120170 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | Naringin generates three types of reactive oxygen species contributing differently to apoptosis-like death in Escherichia coli | Aims: Naringin is a flavonoid with a polyphenolic structure which induces formation of reactive oxygen species (ROS). Although the antibacterial effect of naringin has been demonstrated, the mechanism underlying this effect has not yet been elucidated. We focused on investigating the antibacterial mode of action of naringin in Escherichia coli following ROS generation. The contributions of ROS, hydroxy radicals (OH-), super oxide (O-2(-)), and hydrogen peroxide (H2O2) were investigated. Main methods: ROS accumulation was detected using fluorescence dyes, and all experiments were conducted using the scavenger including tiron, sodium pyruvate, and thiourea to assess the contribution of each ROS. Western blotting assays were used to observe the activation of the SOS response for DNA repair. DNA frag-mentation, membrane depolarization, and phosphatidylserine exposure were estimated using TUNEL, DiBAC4(3), and Annexin V/PI. Key findings: Accumulation of ROS was observed in Escherichia coli after treatment with naringin. Oxidative stress induced cellular dysfunction including DNA damage, which results in SOS response activation. Eventually, apoptosis-like death occurred in cells treated with naringin. The cells had different contributions of each ROS and accompanying apoptotic factors. The ROS most destructive to E. coli was OH-, followed by H2O2 and O-2- . Significance: Due to its efficacy, naringin is a useful antimicrobial agent. An initial investigation into the anti-bacterial mode of action of naringin is presented in this paper. The contribution of each ROS to apoptosis-like cell death (ALD) was investigated, and the results enhanced our understanding of the correlation between the SOS response and oxidative stress in bacteria. | Han, Giyeol; Lee, Dong Gun | Kyungpook Natl Univ, Sch Life Sci, BK FOUR KNU Creat Biores Grp 21, Daegu 41566, South Korea | Lee, Dong-Gun/IWD-9833-2023 | 57363202000; 55668060900 | dglee222@knu.ac.kr; | LIFE SCIENCES | LIFE SCI | 0024-3205 | 1879-0631 | 304 | SCIE | MEDICINE, RESEARCH & EXPERIMENTAL;PHARMACOLOGY & PHARMACY | 2022 | 6.1 | 12.1 | 2.02 | 2025-06-25 | 14 | 17 | Naringin; Apoptosis-like death; Reactive oxygen species; Escherichia coli; SOS response | LIPID-PEROXIDATION; SOS RESPONSE; DNA-DAMAGE; GLUTATHIONE; FRAGMENTATION; MUTAGENESIS; ACTIVATION; MECHANISMS; RADICALS; SELENIUM | Apoptosis-like death; Escherichia coli; Naringin; Reactive oxygen species; SOS response | Anti-Bacterial Agents; Apoptosis; Escherichia coli; Flavanones; Hydrogen Peroxide; Oxidative Stress; Reactive Oxygen Species; aurantiin; DNA; fluorescent dye; hydrogen peroxide; hydroxyl radical; phosphatidylserine; pyruvate sodium; reactive oxygen metabolite; superoxide; thiourea; tiron; antiinfective agent; aurantiin; flavanone derivative; hydrogen peroxide; reactive oxygen metabolite; antibacterial activity; apoptosis; apoptosis like death; Article; controlled study; DNA damage; DNA fragmentation; DNA repair; drug efficacy; Escherichia coli; fluorescence; membrane depolarization; nonhuman; oxidative stress; sos response (genetics); TUNEL assay; Western blotting; apoptosis; metabolism; oxidative stress | English | 2022 | 2022-09-01 | 10.1016/j.lfs.2022.120700 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | Vitamin C alleviates alcoholic liver injury by suppressing neutrophil infiltration in senescence marker protein 30-knockout mice irrespective of its antioxidant effects | Aims: Alcoholic liver disease (ALD) comprises an important component in chronic liver diseases, and its clinical significance has increased due to the high consumption of alcohol worldwide. Vitamin C is a potent antioxidant, and several previous studies have suggested that its therapeutic role in ALD is derived from its antioxidant role. However, its anti-inflammatory role in ALD remains to be elucidated. Especially, the relationship between vitamin C and infiltration of neutrophils in ALD has not been discussed to date. For the reason, the present study investigated the precise role of vitamin C in neutrophil infiltration in ALD. Main methods: In the present study, wild-type C57BL/6 and vitamin C-deficient senescence marker protein 30 knockout mice were pair-fed with a Lieber-DeCarli control or ethanol diet. Ethanol-fed groups were fed with increasing concentrations of EtOH (Lieber-DeCarli control diet for 5 days, 3% EtOH diet for a week, and 5% diet for 2 weeks) with or without vitamin C supplementation. Key findings: Vitamin C dramatically attenuated the ethanol-mediated liver disease in the vitamin C-deficient ethanol-fed mice group by suppressing the infiltration of neutrophils accompanied by less CD68-positive cell infiltration. This attenuating role of vitamin C in neutrophil infiltration in the liver is associated with its protective effect for the ethanol-mediated intestinal damage in vitamin C-deficient ethanol-fed mice. Significance: This study provides a novel possibility of vitamin C to be used as an anti-inflammatory therapeutic agent associated with neutrophil infiltration in ALD, thereby helping to establish strategies for attenuating ALD. | Baek, Su-Min; Lee, Seoung-Woo; Lee, Young-Jin; Choi, Seong-Kyoon; Kim, Hee-Yeon; Seo, Min-Soo; Sung, Soo-Eun; Lee, A-Rang; Kim, Tae-Un; Han, Se-Hyeon; Son, Jun-Hyeok; Park, Sang-Joon; Kim, Tae-Hwan; Jeong, Kyu-Shik; Park, Jin-Kyu | Kyungpook Natl Univ, Coll Vet Med, Dept Vet Pathol, Daegu 41566, South Korea; Daegu Gyeongbuk Inst Sci & Technol DGIST, Core Prot Resources Ctr, Daegu 42988, South Korea; Daegu Gyeongbuk Med Innovat Fdn, Lab Anim Ctr, Daegu 41061, South Korea; Kyungpook Natl Univ, Coll Vet Med, Lab Vet Histol, Daegu 41566, South Korea; Hanyang Univ, Dept Media & Commun, Seoul 04763, South Korea; Kyungpook Natl Univ, Stem Cell Therapeut Res Inst, Daegu 41566, South Korea | Jeong, Kyu-Shik/D-6740-2011 | 57207938426; 57218827581; 57491815500; 55505432500; 58368914700; 35254332100; 56051194000; 57207928983; 57214091908; 57210915063; 57490826800; 7501825941; 57202984578; 7201556460; 35213723500 | jinkyu820@knu.ac.kr; | LIFE SCIENCES | LIFE SCI | 0024-3205 | 1879-0631 | 297 | SCIE | MEDICINE, RESEARCH & EXPERIMENTAL;PHARMACOLOGY & PHARMACY | 2022 | 6.1 | 12.1 | 1.64 | 2025-06-25 | 13 | 13 | Alcoholic liver disease; Inflammation; SMP30; Vitamin C; Neutrophils; Gut-liver axis | OXIDATIVE-STRESS; LIPID-PEROXIDATION; ASCORBIC-ACID; DISEASE; PATHOGENESIS; DEFICIENCY; TRANSPLANTATION; HEPATOCYTES; MECHANISMS; INCREASES | Alcoholic liver disease; Gut–liver axis; Inflammation; Neutrophils; SMP30; Vitamin C | Animals; Antioxidants; Ascorbic Acid; Liver; Liver Diseases, Alcoholic; Mice; Mice, Inbred C57BL; Mice, Knockout; Neutrophil Infiltration; ascorbic acid; CD68 antigen; regucalcin; antioxidant; ascorbic acid; alcohol liver cirrhosis; alcohol liver disease; animal cell; animal experiment; animal tissue; antioxidant activity; Article; C57BL 6 mouse; controlled study; diet; disease association; disease exacerbation; drug mechanism; ethanol diet; fatty liver; immunohistochemistry; intestine injury; knockout mouse; liver protection; male; mouse; neutrophil chemotaxis; nonhuman; oxidative stress; protein blood level; protein expression; protein function; wild type mouse; alcohol liver disease; animal; C57BL mouse; liver; metabolism; neutrophil chemotaxis | English | 2022 | 2022-05-15 | 10.1016/j.lfs.2021.120228 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | Benefits of Stochastic Weight Averaging in Developing Neural Network Radiation Scheme for Numerical Weather Prediction | Stochastic weight averaging (SWA) was applied to improve the radiation emulator based on a sequential neural network (SNN) in a numerical weather prediction model over Korea. While the SWA has advantages in terms of generalization such as the ensemble model, the computational cost is maintained at the same level as that of a single model. In this study, the performances of both emulators were evaluated under ideal and real case frameworks. Various sensitivity experiments using different sampling ratios, activation functions, hidden layers, and batch sizes were also conducted. The emulators showed a 60-fold speedup for the radiation processes and 84%-87% reduction of the total computation. In the ideal simulation, compared to the infrequent radiation scheme by 60 times, SNN improved forecast errors by 5.8%-14.1%, and SWA further increased these improvements by 18.2%-26.9%. In the real case simulation, SNN showed 8.8% and 4.7% improvements for longwave and shortwave (SW) fluxes compared to the infrequent method; however, these improvements decreased significantly after 5 days, resulting in 1.8% larger error for skin temperature. By contrast, SWA showed stable 1-week forecast features with 12.6%, 8.0%, and 4.4% improvements in longwave and SW fluxes, and skin temperature, respectively. Although the use of two hidden layers showed the best performance in this study, it was thought that the optimal number of hidden layers could differ depending on the given problem. Compared to temperature and precipitation observations, all experiments showed a variability of error within 1%, implying that the operational use of the developed emulators is possible. | Song, Hwan-Jin; Roh, Soonyoung; Lee, Juho; Nam, Giung; Yun, Eunggu; Yoon, Jongmin; Kim, Park Sa | Korea Meteorol Adm, Natl Inst Meteorol Sci, Jeju Do, South Korea; Kyungpook Natl Univ, Dept Atmospher Sci, Ctr Atmospher Remote Sensing CARE, Daegu, South Korea; Korea Adv Inst Sci & Technol, Kim Jaechul Grad Sch Artificial Intelligence, Daejeon, South Korea | Lee, Jeehee/JXW-9775-2024; Song, Hwan-Jin/M-1641-2018; Nam, Giung/LXA-4155-2024; Jo, Hyon-Suk/HGC-7070-2022 | 55331697200; 57219226841; 57132050100; 57326039900; 57226256535; 57224904399; 57679295000 | hwanjinsong@gmail.com; | JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS | J ADV MODEL EARTH SY | 1942-2466 | 14 | 10 | SCIE | METEOROLOGY & ATMOSPHERIC SCIENCES | 2022 | 6.8 | 12.2 | 0.51 | 2025-06-25 | 6 | 7 | neural network; stochastic weight averaging; emulator; speedup; WRF; RRTMG | PARAMETERIZATION; ACCURATE; MODEL; APPROXIMATION; EMULATIONS | emulator; neural network; RRTMG; speedup; stochastic weight averaging; WRF | Korea; Numerical models; Stochastic models; Stochastic systems; Weather forecasting; Emulator; Hidden layers; Neural-networks; RRTMG; Sequential neural networks; Speedup; Stochastic weight averaging; Stochastics; Weight averaging; WRF; artificial neural network; climate prediction; stochasticity; weather forecasting; Errors | English | 2022 | 2022-10 | 10.1029/2021ms002921 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | Deep Learning Provides Substantial Improvements to County-Level Fire Weather Forecasting Over the Western United States | The recent wildfires in the western United States during 2018 and 2020 caused record-breaking fire damage and casualties. Despite remarkable advances in fire modeling and weather forecasting, it remains challenging to anticipate catastrophic wildfire events and associated damage. One key missing component is a fire weather prediction system with sufficiently long lead time capable of providing useful regional details. Here, we develop a hybrid prediction model of wildfire danger called CFS with super resolution (CFS-SR) as a proof of concept to fill that void. The CFS-SR model is constructed by integrating the Climate Forecast System version 2 with a deep learning (DL) technique from Single Image Super Resolution, a method widely used in enhancing image resolution. We show that for the 2018-2019 fire season, the CFS-SR model significantly improves accuracy in forecasting fire weather at lead times of up to 7 days with an enhanced spatial resolution up to 4 km. This level of high resolution provides county-level fire weather forecast, making it more practical for allocating resources to mitigate wildfire danger. Our study demonstrates that a proper combination of ensemble climate predictions with DL techniques can boost predictability at finer spatial scales, increasing the utility of fire weather forecasts for practical applications. | Son, Rackhun; Ma, Po-Lun; Wang, Hailong; Rasch, Philp J.; Wang, Shih-Yu (Simon); Kim, Hyungjun; Jeong, Jee-Hoon; Lim, Kyo-Sun Sunny; Yoon, Jin-Ho | Max Planck Inst Biogeochem Jena, Dept Biogeochem Integrat, Jena, Germany; Gwangju Inst Sci & Technol, Sch Earth Sci & Environm Engn, Gwangju, South Korea; Pacific Northwest Natl Lab, Richland, WA 99352 USA; Univ Washington, Dept Atmospher Sci, Seattle, WA 98195 USA; Utah State Univ, Dept Plants Soils & Climate, Logan, UT USA; Korea Adv Inst Sci & Technol, Moon Soul Grad Sch Future Strategy, Daejeon, South Korea; Korea Adv Inst Sci & Technol, Dept Civil & Environm Engn, Daejeon, South Korea; Univ Tokyo, Inst Ind Sci, Tokyo, Japan; Chonnam Natl Univ, Fac Earth & Environm Sci, Gwangju, South Korea; Kyungpook Natl Univ, Dept Atmospher Sci, Ctr Atmospher REmote Sensing CARE, Daegu, South Korea | Jeong, Jee-Hoon/A-4286-2010; Ma, Po-Lun/G-7129-2015; KIM, HYUNGJUN/I-5099-2014; Lim, Kyo-Sun/I-3811-2012; Wang, Hailong/B-8061-2010; YOON, JIN-HO/A-1672-2009 | 57212585017; 15755995900; 55688930000; 7006705919; 56329646700; 55778084100; 8855923200; 57211926026; 55317177900 | yjinho@gist.ac.kr; | JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS | J ADV MODEL EARTH SY | 1942-2466 | 14 | 10 | SCIE | METEOROLOGY & ATMOSPHERIC SCIENCES | 2022 | 6.8 | 12.2 | 0.59 | 2025-06-25 | 8 | 8 | wildfire; fire weather prediction; deep learning; bias correction; downscaling | DANGER RATING SYSTEM; MODEL; NETWORKS; IMAGE | bias correction; deep learning; downscaling; fire weather prediction; wildfire | United States; Climate models; Deep learning; Fires; Image enhancement; Image resolution; Learning systems; Bias correction; County level; Deep learning; Down-scaling; Fire weather; Fire weather prediction; Super-resolution models; Weather prediction; Western United States; Wildfire; climate change; climate modeling; climate prediction; downscaling; image resolution; machine learning; spatial resolution; weather forecasting; wildfire; Weather forecasting | English | 2022 | 2022-10 | 10.1029/2022ms002995 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | Diacetylene-Containing Dual-Functional Liquid Crystal Epoxy Resin: Strategic Phase Control for Topochemical Polymerization of Diacetylenes and Thermal Conductivity Enhancement | Liquid crystal epoxy resins (LCERs) with high thermal conductivity have been drawing significant attention to overcome the thermal conductivity limitation of polymeric composites. Nonetheless, the strategy to enhance the thermal conductivity of LCERs has been primarily focused on improving the well-ordered molecular structure originated from LC phases to reduce phonon scattering. Furthermore, other important factors for the enhancement of thermal conductivity such as intermolecular interaction, fine-tuning of the polymer chain structure, and interchain conjugation have been rarely investigated for LCERs. Here, we introduce a dual-functional LCER enabling the creation of well-ordered microstructures as well as intermolecular pi-conjugation networks synergistically suppressing the phonon scattering. As a key design functional group, the diphenyl-diacetylene (DPDA) mesogen was employed to assemble a highly ordered lamellar microstructure and create interchain pi-conjugation networks via topochemical polymerization of well-organized diacetylenes. The thermal conductivity of cured DPDA epoxy resin with a highly ordered lamellar structure (similar to 0.43 W m(-1) K-1) was 194% compared to a commercial epoxy resin (similar to 0.22 W m(-1) K-1). Thermal conductivity was further increased up to 227% (similar to 0.50 W m(-1) K-1) via post-topochemical polymerization of diacetylenes, leading to pi-conjugation and interchain pi-pi stacking. Furthermore, the thermal conductivity of the composites prepared with hexagonal boron nitride fillers was also increased by 19% after simple heat treatment of the composites, inducing topochemical polymerization of diacetylenes. Finally, a striking thermal conductivity increase from 10.3 W m(-1) K-1 to 18.3 W m(-1) K-1 was observed by simply replacing the matrix from the commercial one to DPDA epoxy resin (DPDAER), clearly revealing the superiority of our DPDAER in the development of high-thermal-conductivity composites. | Hossain, Md Monir; Olamilekan, Arinola Isa; Jeong, Hyun-Oh; Lim, Hongjin; Kim, Young-Kyeong; Cho, Hyunjin; Jeong, Hyeon Dam; Islam, Md Akherul; Goh, Munju; You, Nam-Ho; Kim, Myung Jong; Choi, Siyoung Q.; Hahn, Jae Ryang; Yeo, Hyeonuk; Jang, Se Gyu | Korea Inst Sci & Technol, Funct Composite Mat Res Ctr, Inst Adv Composites Mat, Wonju 55324, Jeonbuk, South Korea; Jeonbuk Natl Univ, Dept Chem, Dept Bioact Mat Sci, Jeonju 54896, Jeonbuk, South Korea; Jeonbuk Natl Univ, Res Inst Phys & Chem, Jeonju 54896, Jeonbuk, South Korea; Kyungpook Nut Tonal Univ, Dept Sci Educ, Daegu 41566, South Korea; Korea Adv Inst Sci & Technol KAIST, Dept Chem & Biomol Engn, Daejeon 34141, South Korea; Konkuk Univ, Dept Chem Engn, Seoul 05029, South Korea; Korea Inst Sci & Technol, Inst Adv Composites Mat, Carbon Composite Mat Res Ctr, Wonju 55324, Jeonbuk, South Korea; Gachon Univ, Dept Chem, Seongnam Si, Gyeonggi Do, South Korea; Kyungpook Natl Univ, Dept Chem Educ, Daegu 41566, South Korea; Kyungpook Natl Univ, Dept Pharm, Daegu 41566, South Korea | Choi, Siyoung/G-5018-2015; Cho, Hyunjin/C-8716-2017; Cho, Hyunjin/ABQ-6349-2022; Hossain, Md. Monir/KWT-7669-2024; Goh, Munju/F-8520-2013; Islam, Ahmad/A-6569-2008; Hossain, Md Monir/NKP-4072-2025; Olamilekan, Arinola isa/AAF-9952-2021; yeo, hyeonuk/G-7890-2017; Yeo, Hyeonuk/AHE-0397-2022 | 57216958154; 57218140505; 57686754600; 57200518483; 57687275400; 55659344000; 57221701751; 57220973638; 8863996900; 55204428300; 55659432400; 36571414300; 7202494378; 55324816500; 7402219010 | jrhahn@jbnu.ac.kr;yeo@knu.ac.kr;segyu.jang@kist.re.kr; | MACROMOLECULES | MACROMOLECULES | 0024-9297 | 1520-5835 | 55 | 11 | SCIE | POLYMER SCIENCE | 2022 | 5.5 | 12.2 | 2.65 | 2025-06-25 | 31 | 28 | CHEMICAL-STRUCTURE; COMPOSITES; MANAGEMENT; POLYMERS; MONOMERS; NETWORK; FILLER | III-V semiconductors; Lamellar structures; Liquid crystals; Phonon scattering; Phonons; Polymerization; Thermal conductivity; Conjugation network; Diacetylenes; Functional liquid; High thermal conductivity; Intermolecular interactions; Liquid crystal epoxy resin; Phase-Control; Polymeric composites; Thermal conductivity enhancement; Topochemical polymerization; Epoxy resins | English | 2022 | 2022-06-14 | 10.1021/acs.macromol.2c00436 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | |||
| ○ | Meeting Abstract | Pediatric diffuse intrinsic pontine glioma treated with radiotherapy: the National multicenter study | Kim, H. J.; Lee, J. H.; Lim, D. H.; Kim, Y.; Park, S.; Ahn, S. D.; Kim, I. A.; Im, J. H.; Chung, J. W.; Kim, J.; Kim, I. H.; Yoon, H. I.; Suh, C. | Gachon Univ, Gil Hosp, Dept Radiat Oncol, Incheon, South Korea; Seoul Natl Univ, Seoul Natl Univ Hosp, Coll Med, Dept Radiat Oncol, Seoul, South Korea; Sungkyunkwan Univ, Sch Med, Samsung Med Ctr, Dept Radiat Oncol, Seoul, South Korea; Kyung Hee Univ, Sch Med, Med Ctr, Dept Radiat Oncol, Seoul, South Korea; Kyungpook Natl Univ, Sch Med, Dept Radiat Oncol, Daegu, South Korea; Univ Ulsan, Coll Med, Asan Med Ctr, Dept Radiat Oncol, Seoul, South Korea; Seoul Natl Univ, Bundang Hosp, Dept Radiat Oncol, Seongnam, South Korea; CHA Univ, Sch Med, CHA Bundang Med Ctr, Dept Radiat Oncol, Seongnam, South Korea; Chonnam Natl Univ, Med Sch, Dept Radiat Oncol, Gwangju, South Korea; Natl Canc Ctr, Proton Therapy Ctr, Dept Radiat Oncol, Goyang, South Korea; Yonsei Univ, Coll Med, Yonsei Canc Ctr, Dept Radiat Oncol, Seoul, South Korea | Kim, In/J-5426-2012; Kim, Dong/F-4608-2014 | RADIOTHERAPY AND ONCOLOGY | RADIOTHER ONCOL | 0167-8140 | 1879-0887 | 170 | SCIE | ONCOLOGY;RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING | 2022 | 5.7 | 12.2 | 0 | English | 2022 | 2022-05 | 바로가기 | 바로가기 | ||||||||||||||||
| ○ | ○ | Article | Selective Localization of Nanofiller on Mechanical Properties ofPoly(lactic acid)/Poly(butylene adipate-co-terephthalate)Nanocomposites via the Surface Energy and Melt BlendingTechnique | The dispersion and localization of nanofillers at theinterface in immiscible polymer blends to prevent phase separationand voids are the most important factors for fabricating nano-composites with outstanding mechanical properties. However, thesefactors are limited to conventional industrial applications, such asmelt blending and extrusion due to the aggregation/agglomerationof the nanofillers during processing. Here, the effects of the meltblending technique and nanofiller surface energy on dispersion andselective localization of the nanofillers in poly(lactic acid) (PLA)/poly(butylene adipate-co-terephthalate) (PBAT) nanocompositewere studied. Consequently, we confirmed that the localization ofmodified silica (m-SiO2) in the nanocomposite could be determined by controlling the PBAT mixing time. Furthermore, the m-SiO2, located at the PLA/PBAT interface with modified cellulose nanofiber, improved the morphology of the PLA/PBATnanocomposites, thereby significantly improving the tensile strength and elongation at break by approximately 7% and 16%,respectively. The results of this study demonstrate a novel approach to control the dispersion and localization of nanofillers inimmiscible polymer blends, thereby paving a new possibility to fabricate eco-friendly packaging materials industrially | Kim, Do Young; Lee, Jae Bin; Lee, Dong Yun | Kyungpook Natl Univ, Dept Polymer Sci & Engn, Daegu 41566, South Korea | ; , Do Young Kim/AAB-1459-2021; Lee, Joonseok/AAP-6003-2021 | 56802861000; 57218880937; 57211001605 | dongyunlee@knu.ac.kr; | MACROMOLECULES | MACROMOLECULES | 0024-9297 | 1520-5835 | 55 | 8 | SCIE | POLYMER SCIENCE | 2022 | 5.5 | 12.2 | 2.94 | 2025-06-25 | 31 | 31 | IMMISCIBLE POLYMER BLENDS; NANO-SILICA PARTICLES; ACID-BASED POLYMERS; CARBON NANOTUBES; POLY(LACTIC ACID); MORPHOLOGY DEVELOPMENT; PERCOLATION-THRESHOLD; REACTIVE EXTRUSION; PLA; NANOPARTICLES | Anatomy; Butenes; Dispersions; Lactic Acid; Mixing; Packaging Materials; Blending; Butenes; Dispersions; Interfacial energy; Lactic acid; Morphology; Packaging materials; Phase separation; Polymer blends; Silica; Silicon; Tensile strength; Blending techniques; Immiscible polymer blends; Localisation; Melt blending; Melt extrusion; Modified silica; Nanofiller; Polies (butylene adipate co terephthalate); Poly lactic acid; Selective localizations; Nanocomposites | English | 2022 | 2022-04-26 | 10.1021/acs.macromol.1c02074 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | |||
| ○ | ○ | Article | The patterns and spatial locations of local recurrence in breast cancer with implant-based reconstruction after mastectomy | Background and purpose: The European Society for Radiotherapy and Oncology (ESTRO) recently defined delineation guidelines for the clinical target volume for postmastectomy radiation therapy (PMRT) after immediate implant-based reconstruction for early-stage breast cancer. We analyzed the three-dimensional location and pattern of local recurrence in accordance with the reconstruction type and ESTRO-target volume. Materials and methods: This retrospective study involved patients who had undergone mastectomy with implant reconstruction between 2010 and 2019 and who had local recurrence as the first event. For mapping analysis, one subpectoral and one prepectoral implant patient were selected. All recurrence lesions were contoured and mapped in a representative case. Results: A total of 1327 patients with breast cancer who underwent mastectomy and implant-based breast reconstruction were identified; 51 were enrolled with a total of 65 lesions. In subpectoral implant patients, 93% of recurrences were located in the ESTRO-target volume. No recurrence occurred in the implant pocket, but 7% of the recurrent tumors developed in the pectoralis major and deep thoracic muscle. In prepectoral implant patients, all recurrent tumors occurred within the ESTRO-target volume. Conclusion: The ESTRO-target volume in PMRT after reconstruction encompassed most local recurrences in patients who underwent mastectomy with immediate implant reconstruction. Our results support the application of the ESTRO Advisory Committee for Radiation Oncology Practice consensus guideline for target volume of PMRT after immediate implant-based reconstruction for early-stage breast cancer. (c) 2022 Elsevier B.V. All rights reserved. Radiotherapy and Oncology 170 (2022) 111-117 | Joo, Ji Hyeon; Yang, Jung Dug; Park, Ho Yong; Park, Jaehyeon; Wu, Zhen-Yu; Ko, BeomSeok; Park, Jongmoo; Kim, Su Ssan | Pusan Natl Univ, Sch Med, Dept Radiat Oncol, Yangsan Hosp, Yangsan, South Korea; Kyungpook Natl Univ, Sch Med, Dept Plast & Reconstruct Surg, Daegu, South Korea; Kyungpook Natl Univ, Sch Med, Dept Surg, Daegu, South Korea; Yeungnam Univ, Dept Radiat Oncol, Coll Med, Daegu, South Korea; Tongji Univ, Shanghai East Hosp, Dept Breast Surg, Sch Med, Shanghai, Peoples R China; Univ Ulsan, Asan Med Ctr, Dept Surg, Div Breast Surg,Coll Med, Seoul, South Korea; Kyungpook Natl Univ, Sch Med, Dept Radiat Oncol, Daegu, South Korea; Univ Ulsan, Asan Med Ctr, Dept Radiat Oncol, Coll Med, 88,Olymp Ro 43 Gil, Seoul 05505, South Korea | PARK, JUN-YOUNG/P-5981-2015; Yang, Jung/R-7806-2019; lee, wj/JNR-4926-2023 | 55888566300; 55171704700; 56564377200; 57208665003; 57210935537; 56781006300; 56180048900; 25627857300 | fauny11@naver.com;watermountain@hanmail.net; | RADIOTHERAPY AND ONCOLOGY | RADIOTHER ONCOL | 0167-8140 | 1879-0887 | 170 | SCIE | ONCOLOGY;RADIOLOGY, NUCLEAR MEDICINE & MEDICAL IMAGING | 2022 | 5.7 | 12.2 | 0.33 | 2025-06-25 | 3 | 3 | Breast cancer; Recurrence patterns; CTV; ESTRO; Implant; Mastectomy | POSTMASTECTOMY RADIATION-THERAPY; NIPPLE-SPARING MASTECTOMY; IMMEDIATE RECONSTRUCTION; CONSENSUS GUIDELINE; TRENDS; RADIOTHERAPY; TISSUE | Breast cancer; CTV; ESTRO; Implant; Mastectomy; Recurrence patterns | Breast Implantation; Breast Neoplasms; Female; Humans; Mammaplasty; Mastectomy; Neoplasm Recurrence, Local; Retrospective Studies; antineoplastic agent; adjuvant chemotherapy; adjuvant radiotherapy; adult; Article; axillary lymph node dissection; breast cancer; breast cancer recurrence; breast radiotherapy; breast reconstruction; breast tissue; cancer localization; cancer patient; cancer size; cancer surgery; clinical target volume; ductal breast carcinoma in situ; female; hormone receptor negative breast cancer; hormone receptor positive breast cancer; human; human epidermal growth factor receptor 2 negative breast cancer; human epidermal growth factor receptor 2 positive breast cancer; intercostal muscle; invasive ductal carcinoma; lymph vessel metastasis; major clinical study; mastectomy; multicenter study (topic); muscle tissue; neoadjuvant chemotherapy; nipple-sparing mastectomy; pectoral muscle; pectoralis major muscle; retrospective study; sentinel lymph node biopsy; simple mastectomy; skin-sparing mastectomy; subcutaneous fat; surgical margin; thorax muscle; three-dimensional imaging; tumor recurrence; tumor volume; ventral region; breast augmentation; breast tumor; mastectomy; pathology; procedures | English | 2022 | 2022-05 | 10.1016/j.radonc.2022.02.028 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | CMASS galaxy sample and the ontological status of the cosmological principle | Context. The cosmological principle (CP), assuming spatially homogeneous and isotropic background geometry in the cosmological scale, is a fundamental assumption in modern cosmology. Recent observations of the galaxy redshift survey provide relevant data to confront the principle with observations. Several previous studies claim that the homogeneity scale is reached at a radius around 70 h(-1) Mpc. However, the same observation shows a dramatic visual structure in the Sloan Digital Sky Survey Great Wall, which extends 300 h(-1) Mpc in linear dimension. Aims. We present a homogeneity test for the matter distribution using the Baryon Oscillation Spectroscopic Survey Data Release 12 CMASS galaxy sample and clarify the ontological status of the CP. Methods. As a homogeneity criterion, we compared the observed data with similarly constructed random distributions using the number count in the truncated cones method. Comparisons are also made with three theoretical results using the same method: (i) the dark matter halo mock catalogs from the N-body simulation, (ii) the log-normal distributions derived from the theoretical matter power spectrum, and (iii) the direct estimation from the theoretical power spectrum. Results. We show that the observed distribution is statistically impossible as a random distribution up to 300 h(-1) Mpc in radius, which is around the largest statistically available scale. However, comparisons with the three theoretical results show that the observed distribution is consistent with these theoretically derived results based on the CP. Conclusions. We show that the observed galaxy distribution (light) and the simulated dark matter distribution (matter) are quite inhomogeneous even on a large scale. Here, we clarify that there is no inconsistency surrounding the ontological status of the CP in cosmology. In practice, the CP is applied to the metric and the metric fluctuation is extremely small in all cosmological scales. This allows the CP to be valid as the averaged background in the metric. The matter fluctuation, however, is decoupled from the small nature of metric fluctuation in the subhorizon scale. What is directly related to the matter in Einstein's gravity is the curvature, which is a quadratic derivative of the metric. | Kim, Yigon; Park, Chan-Gyung; Noh, Hyerim; Hwang, Jai-chan | Kyungpook Natl Univ, Dept Astron & Atmospher Sci, Daegu 41566, South Korea; Jeonbuk Natl Univ, Div Sci Educ, Jeonju 54896, South Korea; Jeonbuk Natl Univ, Inst Sci Educ, Jeonju 54896, South Korea; Korea Astron & Space Sci Inst, Theoret Astrophys Grp, Daejeon 34055, South Korea; Inst Basic Sci IBS, Ctr Theoret Phys Universe, 55 Expo Ro, Daejeon 34126, South Korea | Hwang, James/GOP-3586-2022 | 57376307100; 43361710800; 7103103544; 7403896548 | park.chan.gyung@gmail.com; | ASTRONOMY & ASTROPHYSICS | ASTRON ASTROPHYS | 0004-6361 | 1432-0746 | 660 | SCIE | ASTRONOMY & ASTROPHYSICS | 2022 | 6.5 | 12.3 | 0.92 | 2025-06-25 | 10 | 11 | large-scale structure of Universe; methods: statistical; cosmology: theory | OSCILLATION SPECTROSCOPIC SURVEY; DIGITAL-SKY-SURVEY; BARYON ACOUSTIC-OSCILLATIONS; DATA-RELEASE; ANGULAR MASKS; SCALE; HOMOGENEITY; SIMULATION; CURVATURE; EVOLUTION | Cosmology: theory; Large-scale structure of Universe; Methods: statistical | Cosmology; Gravitation; Normal distribution; Ontology; Power spectrum; Surveys; Cosmological scale; Cosmology: theory; Galaxies: red-shift; Homogeneous and isotropic; Large scale structure of universe; Methods:statistical; Ontological status; Power-spectra; Random distribution; Spatially homogeneous; Galaxies | English | 2022 | 2022-04-26 | 10.1051/0004-6361/202141909 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | High-z Universe probed via Lensing by QSOs (HULQ) II. Deep GMOS spectroscopy of a QSO lens candidate | Galaxies and their central supermassive black holes are known to coevolve, but the physical background for this is unknown as of yet. The High-z Universe probed via Lensing by QSOs (HULQ) project aims to investigate this coevolution by using quasi-stellar object (QSO) host galaxies acting as gravitational lenses (QSO lenses). We present the results of the spectroscopic observation of the first QSO lens candidate from the HULQ project, HULQ J0002+0239, which consists of a QSO host galaxy at z(d) = 1.455 and four seemingly lensed objects in a cross-like configuration. Deep optical spectra of two of the possibly lensed objects with z similar to 24.5 mag were obtained with the Gemini Multi-Object Spectrograph on the Gemini North Telescope. Their spectra reveal that the objects are newly discovered galaxies at z = 0.29 and z = 1.11, and we conclude that HULQ J0002+0239 is not a QSO lens. Our QSO lens search results are so far in agreement with the predicted number of QSO lenses, and we discuss how the future investigation of additional QSO lens candidates could tell us more about the evolution of the black hole mass and host galaxy scaling relations. | Taak, Y. C.; Im, M.; Kim, Y.; Hyun, M.; Paek, I | Univ Calif Los Angeles, Phys & Astron Dept, Los Angeles, CA 90095 USA; Seoul Natl Univ, SNU Astron Res Ctr, 1 Gwanak Ro, Seoul 08826, South Korea; Seoul Natl Univ, Dept Phys & Astron, Astron Program, 1 Gwanak Ro, Seoul 08826, South Korea; Kyungpook Natl Univ, Coll Nat Sci, Dept Astron & Atmospher Sci, Daegu 41566, South Korea; Peking Univ, Kavli Inst Astron & Astrophys, Beijing 100871, Peoples R China; Korea Astron & Space Sci Inst, Daejeon 34055, South Korea | Im, Myungshin/B-3436-2013; , Yong Jung Kim/JRW-0681-2023 | 56436682000; 7004267711; 59622148200; 56435655500; 57205495959 | yctaak@astro.ucla.edu;myungshin.im@gmail.com; | ASTRONOMY & ASTROPHYSICS | ASTRON ASTROPHYS | 0004-6361 | 1432-0746 | 665 | SCIE | ASTRONOMY & ASTROPHYSICS | 2022 | 6.5 | 12.3 | 0 | 2025-06-25 | 0 | 0 | gravitational lensing: strong; quasars: supermassive black holes; galaxies: active; galaxies: evolution | BLACK-HOLE MASS; ACTIVE GALACTIC NUCLEI; SURVEY QUASAR CATALOG; SIMILAR-TO 5; COSMIC EVOLUTION; HOST GALAXIES; FAINT QUASARS; CLASSIFICATION; DECOMPOSITION; SPECTROGRAPH | galaxies: active; galaxies: evolution; gravitational lensing: strong; quasars: supermassive black holes | Black holes; Gravitation; Spectrographs; Stars; Co-evolution; Galaxies active; Galaxy evolution; Gravitational lens; Gravitational lensing: strong; Host galaxies; Optical spectrum; Quasar: supermassive black hole; Quasi-stellar objects; Supermassive black holes; Galaxies | English | 2022 | 2022-08-31 | 10.1051/0004-6361/202142385 | 바로가기 | 바로가기 | 바로가기 | 바로가기 | ||
| ○ | ○ | Article | Jet kinematics in the transversely stratified jet of 3C 84 A two-decade overview | 3C 84 (NGC 1275) is one of the brightest radio sources in the millimetre radio bands, which led to a plethora of very-long-baseline interferometry (VLBI) observations at numerous frequencies over the years. They reveal a two-sided jet structure, with an expanding but not well-collimated parsec-scale jet, pointing southward. High-resolution millimetre-VLBI observations allow the study and imaging of the jet base on a sub-parsec scale. This could facilitate the investigation of the nature of the jet origin, also in view of the previously detected two-railed jet structure and east-west oriented core region seen with RadioAstron at 22 GHz. We produced VLBI images of this core and inner jet region, observed over the past twenty years at 15, 43, and 86 GHz. We determined the kinematics of the inner jet and ejected features at 43 and 86 GHz and compared their ejection times with radio and y-ray variability. For the moving jet features, we find an average velocity of beta(avg)(app) = 0.055 - 0.22c (mu(avg) = 0.04 - 0.18 mas yr(-1)). From the time-averaged VLBI images at the three frequencies, we measured the transverse jet width along the bulk flow. On the <= 1.5 parsec scale, we find a clear trend of the jet width being frequency dependent, with the jet being narrower at higher frequencies. This stratification is discussed in the context of a spine-sheath scenario, and we compare it to other possible interpretations. From quasi-simultaneous observations at 43 and 86 GHz, we obtain spectral index maps, revealing a time-variable orientation of the spectral index gradient due to structural variability of the inner jet. | Paraschos, G. F.; Krichbaum, T. P.; Kim, J-Y; Hodgson, J. A.; Oh, J.; Ros, E.; Zensus, J. A.; Marscher, A. P.; Jorstad, S. G.; Gurwell, M. A.; Laehteenmaeki, A.; Tornikoski, M.; Kiehlmann, S.; Readhead, A. C. S. | Max Planck Inst Radioastron, Hugel 69, D-53121 Bonn, Germany; Korea Astron & Space Sci Inst, 776 Daedeokdae Ro, Daejeon 30455, South Korea; Sejong Univ, Dept Phys & Astron, 209 Neungdong Ro, Seoul 05006, South Korea; Boston Univ, Inst Astrophys Res, Boston, MA 02215 USA; St Petersburg State Univ, Astron Inst, Univ Sky Prospekt 28, St Petersburg 198504, Russia; Ctr Astrophys Harvard & Smithsonian, 60 Garden St, Cambridge, MA 02138 USA; Aalto Univ, Metsahovi Radio Observ, Metsahovintie 114, Kylmala 02540, Finland; Aalto Univ, Dept Elect & Nanoengn, POB 15500, Aalto 00076, Finland; Fdn Res & Technol Hellas, Inst Astrophys, Iraklion 71110, Greece; Univ Crete, Dept Phys, Iraklion 70013, Greece; CALTECH, Owens Valley Radio Observ, Pasadena, CA 91125 USA; Kyungpook Natl Univ, Dept Astron & Atmospher Sci, Daegu 702701, South Korea | ; Hodgson, Jeffrey/AAU-9026-2021; Ros, Eduardo/B-1014-2015; Kim, Jae-Young/IUO-6466-2023; Kiehlmann, Sebastian/G-7253-2019; Lähteenmäki, Anne/L-5987-2013; Jorstad, Svetlana/AAM-3279-2021 | 57224966143; 7004015011; 57211836467; 55622269600; 56318374100; 7102531000; 7004929291; 7004154914; 59785012300; 6602556944; 57202570352; 6601986585; 56023086400; 7005439113 | gfparaschos@mpifr-bonn.mpg.de; | ASTRONOMY & ASTROPHYSICS | ASTRON ASTROPHYS | 0004-6361 | 1432-0746 | 665 | SCIE | ASTRONOMY & ASTROPHYSICS | 2022 | 6.5 | 12.3 | 1.01 | 2025-06-25 | 14 | 13 | galaxies: jets; galaxies: active; galaxies: individual: 3C 84; techniques: interferometric; techniques: high angular resolution | ACTIVE GALACTIC NUCLEI; GAMMA-RAY EMISSION; NGC 1275; MAGNETIC ACCELERATION; SCALE; MILLIMETER; COUNTERJET; DISCOVERY; EVOLUTION; NGC-1275 | galaxies: active; galaxies: individual: 3C 84; galaxies: jets; techniques: high angular resolution; techniques: interferometric | Galaxies; Interferometry; Maps; Radio astronomy; Galaxies active; Galaxies jets; Galaxies: individuals; Galaxy: individual: 3c 84; Jet structure; Radio sources; Spectral indices; Technique: interferometric; Techniques: high angular resolutions; Very long baseline interferometry; Kinematics | English | 2022 | 2022-08-31 | 10.1051/0004-6361/202243343 | 바로가기 | 바로가기 | 바로가기 | 바로가기 |
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