• Title/Summary/Keyword: flare

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Development of Nomographs for the Evaluation of Lighting Energy Performance in a Semi-infinite Office Space (중규모 사무공간에서 조명에너지 성능평가를 위한 노모그래프 개발에 관한 연구)

  • Kim, Han-Seong;Ko, Dong-Hwan;Kim, Kang-Soo
    • Journal of the Korean Solar Energy Society
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    • v.23 no.3
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    • pp.73-80
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    • 2003
  • The purpose of this study was to analyze daylighting performance in a semi-infinite size office space for lighting energy conservation. DOE2.1E was used for simulations for the model space of $12\times12\times2.6m$. Nomographs were developed which could simulate work plane illuminance, glare index, energy consumption rate and energy reduction rate for daylighting design. Major results of simulations are as follows ; 1) When blinds facing south were installed, 43% of workplane illuminance diminished, but the flare index didn't exceed the recommended max-glare value. 2) In a semi-infinite office space facing south. energy consumption rate in the case space of 500 lux workplane illuminance is larger then case space of 300 lux workplane illuminance. Therefore, energy reduction rate is increased when the semi-infinite office faces south and naintains 300 lux workplane illuminance level.

A Study on the Visual Evaluation According to Changes in Silhouette of Wide Pants (와이드 팬츠의 실루엣 변화에 따른 시각적 평가)

  • Lee, Jung-Soon
    • Journal of the Korea Fashion and Costume Design Association
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    • v.15 no.1
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    • pp.21-30
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    • 2013
  • The purpose of this study is to recognize the differences of visual evaluation by variations in silhouette of the wide pants. The stimuli are 9 samples: One control group, 3 variations of the width of hem line and 3 variations of the silhouette. The data has been obtained from 57 fashion college students. The data has been analyzed by Factor Analysis, Anova, Scheffe's Test. The results of the study are as follows: The visual evaluation by silhouette of wide pants are composed of 5 factors(i.e., physical characteristics, complexity, attractiveness, originality, and stiffness and softness). Among these factors, the physical characteristic is evaluated to be the most important factor. The straight pants were the most attractive and modern when the width of the hem line was 66cm (1st stage), while the pants were uncomfortable and unwearable when the width of the hem line was 98cm (3rd stage). The bell-bottom pants were evaluated to be the most attractive with the average width of the hem line. When the width of the hem line of the flare pants were too wide, it was uncomfortable and unwearable but had its unique originality. When the width of the hem line was narrow, the visual image changed as the pants' silhouette varied. However, when the width of the hem line was wide, the visual image did not change by silhouette.

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대전 지역의 지자기 변동 지수

  • 임무택
    • Proceedings of the KSEEG Conference
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    • 2000.04b
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    • pp.146-150
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    • 2000
  • 한국자원연구소는 1998년에 영국지질조사소가 설계, 제작한 FLARE+ 지자기연속관측시스템 한 대를 한국자원연구소 내에 설치하고, 연속적인 관측을 수행하고 있으며, 이 관측소를 IAGA 에 등록하고 국제지자기관측소식별부호 DZN을 받았다. 이 시스템은 5초 간격으로 지자기장의 3 성분을, 1분 간격으로 총자기장을 측정하여, 1분 평균자료를 생산하고 있다. 지자기 관측자료? 활용 분야들 중 하나인 지역적 지자기 변동지수(local K index)를 게산하였다. 이를 위해서는 1999년 3월 2일부터 18일까지 17일 동안 관측자료를 기초자료로 하였고, 대전지역의 최대변동폭을 300 nT로 가정하였다. 그결과, 지자기의 최대 변동 지수 폭을 0~9 까지로 할 때, 사용된 자료로 계산한 지역적 지자기 변동지수는 1~6사이에 분포하였고, 최대빈도의 변동지수 3이었다. 한편, IAGA가 계산한 같은 기간의 전지구적 지자기 변동지수(planetary k index)는 0~6사이에 부포하였으며, 최도빈도의 변동지수는 역시 3이었다. 위 기간 동안의 대전의 지역적 변동지수 수열과 전지구적 지자기 변동지수 (planetary K index) 수열 사이의 상관계수(cross correlation coefficient coefficient)는 0.66563이었다. 이것은 지역적 변동지수가 전지구적 변동지수 같은 방향으로 변화하고 있음을 뜻하며, 지역적 변동지수를 해당 지역의 지자기 변동을 대표하는 값으로 쓸수 있음을 뜻한다.

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Natural History of Rotator Cuff Disorders (회전근 개 질환의 자연경과)

  • Oh Jeong-Hwan;Park Jin-Young
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.3 no.2
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    • pp.93-97
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    • 2004
  • Continued research needs to be devoted to understanding the natural history of rotator cuff tears. Recent studies have shown progression of tear, symptomatic flare-ups and irreversible change in rotator cuffs managed nonsurgically. These data allow the grouping of patients with rotator cuff tears into three categories based on risk-benefit ratios. Nonsurgical care should be maximized for patients with impingement symptoms only, with partial-thickness tears, with chronic tears, and for the elderly patients. The proper selection of candidates for nonsurgical management should lead to the high success rate quoted by multiple authors. Even though conservative treatment is necessary, early surgery should be considered for tears that are acute, small or medium, associated with shoulder loss of function, or occur in a younger patient. Prolonged nonsurgical care in these patients risks tear propagation and irreversible changes to the cuff, which may complicate rotator cuff repair.

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Burst Locating Capability of the Korean Solar Radio Burst Locator (KSRBL)

  • Hwangbo, Jung-Eun;Bong, Su-Chan;Park, Sung-Hong;Lee, Dae-Young;Cho, Kyung-Suk;Lee, Jaejin;Park, Young-Deuk
    • Journal of Astronomy and Space Sciences
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    • v.32 no.1
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    • pp.91-99
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    • 2015
  • The Korean Solar Radio Burst Locator (KSRBL) is a solar radio spectrograph observing the broad frequency range from 0.245 to 18 GHz with the capability of locating wideband gyrosynchrotron bursts. Due to the characteristics of a spiral feed, the beam center varies in a spiral pattern with frequency, making a modulation pattern over the wideband spectrum. After a calibration process, we obtained dynamic spectra consistent with the Nobeyama Radio Polarimeter (NoRP). We compared and analyzed the locations of bursts observed by KSRBL with results from the Nobeyama Radioheliograph (NoRH) and Atmospheric Imaging Assembly (AIA). As a result, we found that the KSRBL provides the ability to locate flaring sources on the Sun within around 2'.

Park-Weir Excision for Flaring Alar Correction (넓어진 콧방울의 교정을 위한 Park-Weir 절제술)

  • Han, Sung-Bum;Park, Beyoung-Yun
    • Archives of Plastic Surgery
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    • v.38 no.5
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    • pp.674-678
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    • 2011
  • Purpose: Straight closure line of classic Weir excision leaves visible scars and makes it difficult to precisely approximate resection margins. Hence this study introduces Park-Weir excision that effectively reduces alar width with minimal alar rim scar by 3-dimensional zigzag incision and properly controls the approximation of edges. Methods: From 2008 to 2010, 14 patients underwent Park-Weir excision, crossed wedge excision on alar rim not exceeding 5 mm in width. Each patient was photographed in the same position. Alar width and columellar height against intercanthal distance was compared preoperatively and postoperatively, using image analysis software. Results: Five patients were female and nine were male. Average follow up period was 8 month. Alar width was reduced by 50.50% to 45.96%, original alar width reduced by 8.98% without significant changes in columellar height which was reduced by 0.39%. No visible scar was reported during outpatient follow-up. Conclusion: Park-Weir excision effectively reduces alar width and corrects the flaring of alar without affecting the columellar height. Zigzag incision of Park-Weir excision leaves aesthetically more pleasant scar than straight single incision of classical Weir excision.

Study on Performance of Radiant Heat Shields for Offshore Installations (해양플랜트 복사열 차폐막의 차폐성능에 관한 연구)

  • Kim, Bong Ju
    • Journal of Ocean Engineering and Technology
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    • v.33 no.4
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    • pp.330-339
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    • 2019
  • Radiant heat shields are normally installed on offshore oil and gas platforms to protect personnel, equipment, and structures from the thermal radiation emitted by a flare system. A heat shield should be individually designed to reduce the thermal radiation to the target level, and then manufactured and installed after the performance verification. However, in general, a heat shield is designed and manufactured by trial and error based on the performance test. For this reason, it is difficult to develop and design radiant heat shields in the Korean shipbuilding and marine equipment industry because of the lack of performance test data and limited experience. In the present study, the results of experiments conducted to verify the performances of radiant heat shields were analyzed, and the thermal radiation characteristics and performance characteristics of the radiant heat shields were investigated. The insights and conclusions developed in the present study will be useful in terms of the design and development of radiant heat shield, as well as in their performance verification tests.

Identification Of Jet Components Of CTA 102 On Milliarcsecond Scales Using The iMOGABA Program

  • Kim, Sang-Hyun;Lee, Sang-Sung;Hodgson, Jeffrey A.;Lee, Jee Won;Kang, Sincheol;Yoo, Sung-Min
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.76.1-76.1
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    • 2019
  • CTA 102, one of gamma-ray bright active galactic nuclei (AGN) has been observed with Korean very long baseline interferometry (VLBI) network (KVN) during the period of 2012 December-2018 May as part of interferometric Monitoring Of Gamma-ray Bright AGN (iMOGABA). Multi-frequency VLBI observations enable us to compare the milliarcsecond(mas)-scale iMOGABA images of relativistic jets with those from the Monitoring Of Jets in AGN with Very long baseline array (VLBA) Experiments (MOJAVE) and the VLBA-Boston University(BU)-BLAZAR programs which use VLBA with its angular resolutions of 0.2-1.3 mas. In spite of the relative larger beam sizes of KVN (1-10 mas), we are able to identify jet components of CTA 102 using the KVN multi-frequency VLBI observations with those resolved with VLBA. Considering an instrumental beam blending effect on the jet component identification, we were able to obtain a blending shift of the core position based on a convolution analysis using the VLBA data. When we apply the core position shift to the KVN images of CTA 102, we find that the identified jet components of CTA 102 from the KVN observations are well matched with those from the VLBA observations. Based on the results of the analysis, we may be able to study the jet kinematics and its correlation with gamma-ray flare activity.

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Dependence of tidal disruption flares on stellar density profile and orbital properties

  • Park, Gwanwoo;Hayasaki, Kimitake
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.48.2-48.2
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    • 2019
  • Tidal disruption events (TDEs) provide evidence for quiescent supermassive black holes (SMBHs) in the centers of inactive galaxies. TDEs occur when a star on a parabolic orbit approaches close enough to a SMBH to be disrupted by the tidal force of the SMBH. The subsequent super-Eddington accretion of stellar debris falling back to the SMBH produces a characteristic flare lasting several months. It is theoretically expected that the bolometric light curve decays with time as proportional to $t^{-5/3}$. However, some of the observed X-ray light curves deviate from the $t^{-5/3}$ decay rate, while some of them are overall in good agreement with the $t^{-5/3}$ law. Therefore, it is required to construct the theoretical model for explaining these light curve variations consistently. In this paper, we revisit the mass fallback rates semi-analytically by taking account of the stellar internal structure, orbital eccentricity and penetration factor. We find that the mass fallback rate is shallower than the standard $t^{-5/3}$ decay rate independently of the polytropic index, and the orbital eccentricity only changes the magnitude of the mass fallback rate. Furthermore, the penetration factor significantly can modify the magnitude and variation of mass fallback rate. We confirm these results by performing the computational hydrodynamic simulations. We also discuss the relevance of our model by comparing these results with the observed light curves.

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Case Report of a Pilot with Atopic Dermatitis (아토피성 피부염을 가진 조종사의 판정 증례보고)

  • Kwon, Young Hwan
    • Korean journal of aerospace and environmental medicine
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    • v.31 no.2
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    • pp.54-56
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    • 2021
  • Atopic dermatitis is a condition that makes skin red and itchy. It is common in children but can occur at any age. Atopic dermatitis is chronic and tends to flare periodically. The pathogenesis of the disease has not yet been clearly elucidated but genetic predisposition, immunological dysfunction, and environmental factors are presumed to be involved in the pathogenesis. In general, it is difficult to cure, but as time passes, most of them heal naturally and the symptoms disappear, but the symptoms continue to recur. So, the basic treatment is to relieve the pruritus and prevent it from reoccurring. Treatment involves avoiding things that make the condition worse, daily bathing with application of moisturizing cream afterwards, applying steroid creams when flares occur, and medications to relieve itching sensation. Steroid pills or creams based on calcineurin inhibitors may occasionally be used if other measures are not effective. When examining a pilot with atopic dermatitis, the dermatitis condition, the treatment being used, and the side effects of the medications should be considered. This case involves an otherwise healthy applicant for the 1st class medical certification who has had atopic dermatitis.