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Gravitational waves from the vacuum decay with LISA

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Chinese Physics C 2022年第7期46卷 189-200页

作者： Bum-hoon lee Wonwoo lee Dong-han Yeom Lu Yin Center for Quantum Spacetime Sogang University Seoul 04107 Kora Department of Physics Sogang UniversitySeoul 04107Korea Asia Pacific Center for Theoretical Physics PostechPohang 37673Korea Department of Physics Education Pusan National UniversityBusan 46241Korea Research Center for Dielectric and Advanced Matter Physics Pusan National UniversityBusan 46241Korea

We investigate the gravitational wave spectrum originating from the cosmological first-order phase *** compare two models:one is a scalar field model without gravitation,while the other is a scalar field model with *** on the sensitivity curves of the LISA space-based interferometer on the stochastic gravitational-wave background,we compare the difference between the gravitational wave spectra of the former and the latter cases obtained from the bubble collision *** particular,we numerically calculate the speed of the bubble wall before collision for the two *** demonstrate that the difference between the amplitudes of these spectra can clearly distinguish between the two *** expect that the LISA with Signal to Noise Ratio=10 could observe the spectrum as the fast first-order phase transition.

关键词： gravitational wave first order phasetransition bubble collision

Aortoduodenal fistula and aortic aneurysm secondary to biliary stent-induced retroperitoneal perforation

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World Journal of Gastroenterology 2008年第19期14卷 3095-3097页

作者： Tae hoon lee Do Hyun Park Ji-Young Park Suck-Ho lee Il-Kwun Chung Hong Soo Kim Sang-Heum Park Sun-joo Kim Division of Gastroenterology Department of Internal MedicineSoonchunhyang University College of Medicine Division of Gastroenterology Department of Internal MedicineUniversity of Ulsan College of Medicine

Duodenal perforations caused by biliary prostheses are not uncommon, and they are potentially life threatening and require immediate treatment. We describe an unusual case of aortic aneurysm and rupture which occurred after retroperitoneal aortoduodenal fistula formation as a rare complication caused by biliary metallic stent-related duodenal perforation. To our knowledge, this is the first report describing a lethal complication of a bleeding, aortoduodenal fistula and caused by biliary metallic stent-induced perforation.

关键词： Stents Retroperitoneal perforation Aorticaneurysm Fistula

Deformation prediction of porcelain-enameled steels with strain history by press forming and high-temperature behavior of coating layer

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中国有色金属学会会刊：英文版 2012年第S3期22卷 838-844页

作者： Young-Ki SON Chan-joo lee Jung-Min lee Byung-Min KIM School of Mechanical Engineering Pusan National University Dongnam Regional Division Korea Institute of Industrial Technology

Porcelain enamel coatings were widely applied for the protection of steel products because they offered high corrosion protection,resistance to heat and abrasion,high hardness,hygiene and ease of *** typical process to produce enameled steels is roughly divided into two stages:the first stage consists of a forming process to give the desired shape to a steel substrate,and the second stage consists of a firing process to bond enamel frits on the *** firing process requires a high temperature above 800 °C,which may lead to austenitic transformation and severe thermal deformation of the steel *** aim of this study is to develop a finite element analysis (FE analysis) technique to predict the mechanical and thermal deformations of the enameled steels during forming and any further enameling process,including *** FE analysis involves analyzing the strain history of the steel substrate,which comprises the stress and thickness distributions of the substrate and its deformed shape,and the high-temperature behavior of the enamel coating *** validity of the FE analysis is verified through the U-bending test and firing test with various numbers and positions of enamel coating layers on the *** results reveal that the FE analysis results agree well with the experimental results with 8% error.

关键词： porcelain enamel firing process finite element analysis enameled steel thermal deformation

Observational Study of Surface Wind along a Sloping Surface over Mountainous Terrain during Winter

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Advances in Atmospheric Sciences 2018年第3期35卷 276-284页

作者： Young-Hee lee Gyuwon lee Sangwon joo Kwang-Deuk AHN Department of Astronomy and Atmospheric Sciences Kyungpook National University Numerical Data Application Division Numerical Modeling Center

The 2018 Winter Olympic and Paralympic Games will be held in Pyeongchang, Korea, during February and March. We examined the near surface winds and wind gusts along the sloping surface at two outdoor venues in Pyeongchang during February and March using surface wind data. The outdoor venues are located in a complex, mountainous terrain, and hence the near-surface winds form intricate patterns due to the interplay between large-scale and locally forced winds. During February and March, the dominant wind at the ridge level is westerly; however, a significant wind direction change is ob- served along the sloping surface at the venues. The winds on the sloping surface are also influenced by thermal forcing, showing increased upslope flow during daytime. When neutral air flows over the hill, the windward and leeward flows show a significantly different behavior. A higher correlation of the wind speed between upper- and lower-level stations is shown in the windward region compared with the leeward region. The strong synoptic wind, small width of the ridge, and steep leeward ridge slope angle provide favorable conditions for flow separation at the leeward toot of the ridge. The gust factor increases with decreasing surface elevation and is larger during daytime than nighttime. A significantly large gust factor is also observed in the leeward region.

关键词： flow separation gust factor leeward region sloping surface

Significance of incidental focal fluorine-18 fluorodeoxyglucose uptake in colon/rectum,thyroid,and prostate:With a brief literature review

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World Journal of Clinical Cases 2022年第34期10卷 12532-12542页

作者： Haejun lee Kyung-hoon Hwang Department of Nuclear Medicine Gachon University College of MedicineGil Medical CenterIncheon 21565South Korea

BACKGROUND Fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography(F-18 FDG PET/CT),a functional imaging method,is usually performed on the entire torso,and regions of unexpected suspicious focal hypermetabolism are not infrequently *** the regions,colon,thyroid,and prostate were found to be the common organs in a recent umbrella *** studies reported that a high rate of malignancy was shown in incidentally identified focal hypermetabolic regions and suggested that further examinations should not be *** To investigate the malignancy rate of incidental focal FDG uptake,useful PET parameters and their cutoffs in discrimination between malignant and benign *** Retrospectively,the final reports of 16510 F-18 FDG PET/CT scans performed at our hospital between January 2016 and March 2022 were reviewed to identify incidentally observed FDG uptake in the colon/rectum,thyroid,and *** scans of patients with current or prior malignancies at each corresponding location,without the final reports of histopathology or colonoscopy(for colon and rectum)for the corresponding hypermetabolic regions,or with diffuse(not focal)hypermetabolism were ***,88 regions of focal colorectal hypermetabolism in 85 patients(48 men and 37 women with mean age 67.0±13.4 years and 63.4±15.8 years,respectively),48 focal thyroid uptakes in 48 patients(12 men and 36 women with mean age 62.2±13.1 years and 60.8±12.4 years,respectively),and 39 focal prostate uptakes in 39 patients(mean age 71.8±7.5 years)were eligible for this *** those unexpected focal hypermetabolic regions,rates of malignancy were calculated,PET parameters,such as standardized uptake value(SUV),capable of distinguishing between malignant and benign lesions were investigated,and the cutoffs of those PET parameters were determined by plotting receiver operating characteristic *** In the colon and rectum,29.5%(26/88)were malignant and 33.0%(2

关键词： Incidental Focal Uptake Fluorine-18 fluorodeoxyglucose Positron emission tomography/computed tomography Standardized uptake value

Inorganic shell nanostructures to enhance performance and stability of metal nanoparticles in catalytic applications

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Rare Metals 2020年第7期39卷 767-783页

作者： Inhee Choi Hyeon Kyeong lee Gyoung Woo lee Jiyull Kim Ji Bong joo Department of Life Science University of SeoulSeoul 02504Republic of Korea Division of Chemical Engineering Konkuk UniversitySeoul 05029Republic of Korea

In this article,we review the recent progress and our research activity on the synthesis of inorganic shell nanostructures to enhance the catalytic performance and stability of metal nanoparticles in catalytic ***,we introduce general synthetic strategies for the fabrication of inorganic nanoscale shell layers,including template-assisted sol-gel coating,hydrothermal(or solvothermal)synthesis and the self-templating *** also discuss recent examples of metal nanoparticles(NPs)with nanoscale shell layers,namely core-shell,yolk-shell and multiple NPs-embedded nanoscale *** then discuss the performance and stability of metal particles in practical catalytic ***,we conclude with a summary and perspective on the further progress of inorganic nanostructure with nanoscale shell layers for catalytic applications.

关键词： Nanostructures Inorganic shell Metal nanoparticle Stabilization Performance enhancement Catalyst

Annual Energy Production Estimation for Variable-speed Wind Turbine at High-altitude Site

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Journal of Modern Power Systems and Clean Energy 2021年第3期9卷 684-687页

作者： Dongran Song Songyue Zheng Sheng Yang Jian Yang Mi Dong Mei Su Young hoon joo the School of Automation Central South UniversityChangsha 410083China the School of Energy Science and Engineering Central South UniversityChangsha 410083China the School of IT Information and Control Engineering Kunsan National UniversityKunsan 573701Korea

This letter presents a systematic approach to estimate the annual energy production(AEP) of variable-speed wind turbines erected at high-altitude sites. Compared with the existing empirical-model based approaches, the proposed approach models the influence of the air density on the power production while employing the theoretical power curve. Consequently, the proposed approach provides a precise estimation of AEP, which can serve as a foundation of the optimum turbinesite matching design at different-altitude sites.

关键词： Variable-speed wind turbine annual energy production high-altitude site turbine-site matching

Prostate only radiotherapy using external beam radiotherapy:A clinician’s perspective

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World Journal of Clinical Cases 2022年第29期10卷 10428-10434页

作者： Jeong Won lee Mi joo Chung Department of Radiation Oncology Daegu Catholic University School of MedicineDaegu 42472South Korea Department of Radiation Oncology Hanyang University Hanmaeum Changwon HospitalChangwon 51139South Korea

Prostate-only radiotherapy(PORT) is widely used as the definitive treatment for localized prostate *** cancer has an α/β ratio;therefore,radiotherapy(RT) with a large fraction size is biologically effective for tumor *** current external beam RT technique for PORT has been improved from threedimensional conformal RT to intensity-modulated,stereotactic body,and imageguided *** methods are associated with reduced radiation exposure to normal tissues,decreasing urinary and bowel *** trials have shown improved local control with dose escalation through the aforementioned methods,and the efficacy and safety of intensity-modulated and stereotactic body RTs have been ***,the management of RT in patients with prostate cancer has not been fully *** a clinician,there are several concerns regarding the RT volume and dose considering the patient’s age and ***,this review aimed to discuss the radiobiological basis and external beam technical advancements in PORT for localized prostate cancer from a clinician’s perspective.

关键词： Prostate cancer Radiotherapy Radiation dose Radiation technique Radiation volume

Effect of Annealing Atmosphere on the Mechanical Property of Free-cutting Phosphor Bronze Alloy

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Journal of Materials Science & Technology 2008年第1期24卷 115-119页

作者： Byoung-Soo lee hoon Cho Hyung-Ho Jo Nano Material Team Advanced Material Division Korea Institute of Industrial Technology Incheon 406-800 Korea

The present work is focused on the influence of annealing atmosphere on the microstructure and mechanical property of free-cutting phosphor bronze *** annealing of the alloy was conducted in the three kinds of annealing atmosphere such as air,vacuum and *** annealing,a discernable difference in recystallized grain size and lead particle size was not appeared with different annealing *** tensile strength of the alloy annealed in air or nitrogen atmosphere was higher than that of those annealed in vacuum *** thecase of the alloy annealed in vacuum atmosphere,the mechanical strength was reduced by vaporization of *** the case of annealing in nitrogen and in air atmosphere,the sweating of lead was ***,the inverse segregation of lead was suppressed by copper oxide layer on the surface annealed in *** copper oxide layer leads to a decrease of the yield during fabrication process. Therefore,annealing of the alloy in nitrogen atmosphere is favorable in terms of the mechanical strength and yield.

关键词： Free-cutting Phosphor bronze alloy Inverse segregation Vaporization Sweating