• 천문학회보
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• 제43권1호
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• pp.34.2-35
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• 2018

Galaxy transition from star-forming to quiescent, accompanied with morphology transformation, is one of the key unresolved issues in extragalactic astronomy. Although several environmental mechanisms have been proposed, a deeper understanding of the impact of environment on galaxy transition still requires much exploration. My Ph.D. thesis focuses on which environmental mechanisms are primarily responsible for galaxy transition in different environments and looks at what happens during the transition phase using multi-wavelength photometric/spectroscopic data, from UV to mid-infrared (MIR), derived from several large surveys (GALEX, SDSS, and WISE) and our GMOS-North IFU observations. Our multi-wavelength approach provides new insights into the *late* stages of galaxy transition with a definition of the MIR green valley different from the optical green valley. I will present highlights from three areas in my thesis. First, through an in-depth study of environmental dependence of various properties of galaxies in a nearby supercluster A2199 (Lee et al. 2015), we found that the star formation of galaxies is quenched before the galaxies enter the MIR green valley, which is driven mainly by strangulation. Then, the morphological transformation from late- to early-type galaxies occurs in the MIR green valley. The main environmental mechanisms for the morphological transformation are galaxy-galaxy mergers and interactions that are likely to happen in high-density regions such as galaxy groups/clusters. After the transformation, early-type MIR green valley galaxies keep the memory of their last star formation for several Gyr until they move on to the next stage for completely quiescent galaxies. Second, compact groups (CGs) of galaxies are the most favorable environments for galaxy interactions. We studied MIR properties of galaxies in CGs and their environmental dependence (Lee et al. 2017), using a sample of 670 CGs identified using a friends-of-friends algorithms. We found that MIR [3.4]-[12] colors of CG galaxies are, on average, bluer than those of cluster galaxies. As CGs are located in denser regions, they tend to have larger early-type galaxy fractions and bluer MIR color galaxies. These trends can also be seen for neighboring galaxies around CGs. However, CG members always have larger early-type fractions and bluer MIR colors than their neighboring galaxies. These results suggest that galaxy evolution is faster in CGs than in other environments and that CGs are likely to be the best place for pre-processing. Third, post-starburst galaxies (PSBs) are an ideal laboratory to investigate the details of the transition phase. Their spectra reveal a phase of vigorous star formation activity, which is abruptly ended within the last 1 Gyr. Numerical simulations predict that the starburst, and thus the current A-type stellar population, should be localized within the galaxy's center (< kpc). Yet our GMOS IFU observations show otherwise; all five PSBs in our sample have Hdelta absorption line profiles that extend well beyond the central kpc. Most interestingly, we found a negative correlation between the Hdelta gradient slopes and the fractions of the stellar mass produced during the starburst, suggesting that stronger starbursts are more centrally-concentrated. I will discuss the results in relation with the origin of PSBs.

• 한국수자원학회논문집
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• 제51권4호
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• pp.301-311
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• 2018

지구 온난화가 심화됨에 따라 도시지역에서 집중호우에 의한 침수 피해가 증가하는 추세이다. 이러한 지구온난화에 의한 기후변화의 변동성은 IPCC 5차 보고서(2014)에서도 기술되어 있으며 기후변화에 의한 강수 패턴의 변화, 수문시스템의 변화 등 수자원 불확실성의 증가에 대하여 시사하고 있다. 최근 서울이나 부산과 같은 대도시의 관로의 수용 범위를 초과하는 국지성 호우가 발생하여 큰 피해를 초래하였다. 도시지역의 침수는 1차적으로 우수관거 통수능 부족에 의한 내수범람이 발생하고 방류구와 인접한 하천의 외수범람이 발생한다. 인구가 밀집되어 있는 도시지역에서 발생하는 침수는 인명피해 뿐만 아니라 도로, 교량, 지하공간 침수 및 파괴를 복구하기 위한 사회 경제적 피해를 동반하기 때문에 농촌, 산지 지역에 비해 피해량이 크다. 또한 도시개발에 인한 불투수면적 증가, 강우 유출시 출구부까지의 짧은 도달시간, 배수시설의 통수능부족 등 다양한 원인이 침수피해를 증대시킨다. 본 연구에서는 집중호우에 취약한 지역을 선정하고 XP-SWMM을 이용하여 내수침수 모의를 실시하였다. 또한 시범지역에 관로 개량, 우수저류지 설치, 우수펌프장 설치와 같은 홍수방어대안을 적용하여 각각의 침수모의를 실시하였으며 해당유역을 격자별로 분할하여 대안별 침수데이터를 추출하였다. 또한 격자별로 가장 적합한 구조적 홍수방어대안을 제시하기 위해 침수시간, 최대침수심, 구조물 설치비용을 평가요소로 이용하였으며 MCDM 기법 중 하나인 Compromise Programming 기법을 적용하였다. 본 연구에서는 동일 유역이라도 지리적 여건에 따라 대안의 선호도가 다르다는 점을 반영하고자 하였으며, Spatial Multi-Criteria Decision Making을 적용하여 지역특성을 고려한 홍수방어대안을 선정하는 방법에 대하여 연구하였다.

• 대한지하수환경학회지
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• 제3권1호
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• pp.27-36
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• 1996

난지도 매립지는 바닥차수재나 침출수 차집시설과 같은 오염방지시설이 전혀 설치되어 있지 않은 대표적인 불량 매립지로써 투수성 충적층상에 조성되어 현재 그 인근 지하수와 지표수환경에 심각한 악영향을 미치고 있다. 침출수에 의해 오염된 주변 지하수환경의 오염운(구간) 탐지시 사용할 수 있는 오염지시인자를 결정하고 난지도 매립지를 중심으로 거리별로 설치된 10개의 관측정과 1개의 BTMW＊정을 이용하여 물시료를 채취 분석하거나 Electric data logger를 이용하여 그 오염물질의 수직 및 수평적인 분포특성을 파악하였다. 그 결과 온도와 전기전도도는 매립지에서 가까운 지점일수록 높았으며 침출수는 지표하 85 m 지점까지 거동하였다. 오염성분중 전기전도도와 온도는 매립지 인근지에서 오염지시인자임이 판명되었다. 완전스크린설치정(Fully screened well)에서 측정한 오염물질의 심도별 농도는 공내 전구간을 통해 일정하거나 하부구간이 약간 높은데 반해 BTMW에서 측정한 오염물질의 농도는 심도가 깊어짐에 따라 점이적으로 감소하였다. 이는 상하구간이 완전히 관통된 완전스크린설치정에서는 오염물질의 온도나 밀도차이 혹은 침출수의 수직흐름 때문에 농도가 공내에서 평준화되었기 때문이다. 따라서 매립지 인근지역에서 침출수의 수직 및 수평분포상태나 그 거동을 규명하기 위해서는 BTMW나 다점시료 채취정(multi level sampling well)을 이용하여 물시료를 채취 분석한 값을 이용해야 한다.

• 서비스연구
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• 제14권1호
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• pp.63-76
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• 2024

공동주택은 사람들이 생활하고 거주하는 중요한 장소이자 소통 공간으로서 그 주거 환경의 좋고 나쁨이 주민의 행복감과 안정감에 직접적인 영향을 미치기 때문에 이에 기반한 공동주택의 범죄예방디자인(CPTED)이 필요하다. 하지만, 중국의 범죄 관련 데이터를 대중에게 공개하지 않고 있어 중국의 학자들은 정확한 범죄 데이터에 대한 추가적인 연구를 수행하기 어려운 상황이다. 이로 인해 범죄예방 측면에서 범죄예방디자인의 이론 구축과 적용이 늦어지고 있다. 본 연구는 공동주택의 범죄예방디자인에 대한 소비자의 인식, 각 요소의 중요도, 공동주택 범죄예방디자인 인식개선 방안 등 세 가지 측면을 연구하여 공동주택의 범죄예방디자인 원칙을 효과적으로 개선하고, 공공의 안전을 향상하는 것을 목적으로 하고 있다. 본 연구는 중국 주택 소비자의 범죄예방에 대한 인지도를 파악하기 위해 관련 연구 보고서와 선행문헌을 통해 중국 범죄예방디자인의 현황 및 개발 동향을 조사했다. 또한, 중국 소비자의 공동주택에 대한 범죄예방디자인 인식과 공동주택 범죄예방디자인 각 요소의 중요도 와 인식개선 방안을 파악하기 위해 중국 소비자들을 대상으로 설문조사를 실시하였다. 리커트 척도(Likert Scale)에 기반한 설문 조사와 통계 패키지인 SPSS의 신뢰도 분석을 이용하여 공동주택 범죄예방디자인의 인지 상황, 각 요소의 중요도와 개선 방안을 도출하였다. 본 연구가 실제 효과에 대한 검증이 부족한 점을 고려할 때, 향후 연구에서는 범죄예방디자인의 효과를 검증하고 보다 실질적인 결과를 도출하는 연구가 필요하다. 더불어, 지역 특성에 맞는 안전 솔루션을 도입하고 주민들의 안전 의식을 높이는 교육과 정보 확산을 통해 지역사회의 안전을 촉진하는 방안을 연구하는 것도 중요하다. 연구 결과를 통해 도출된 공동주택의 범죄예방디자인에 대한 인식도와 각 요소의 중요도 및 개선 방안은 향후 중국 지역을 기반으로 한 공동주택 범죄예방디자인 개발에 기초 자료로 활용되길 기대한다.

• 간호행정학회지
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• 제22권5호
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• pp.496-506
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• 2016

Purpose: This study was conducted to examine the adaptation experience of male nurses working in general wards. Methods: Experiential data was collected from 16 general ward nurses through in-depth interviews. Participants were selected from male nurses working in the general wards with over one year of clinical experience at a tertiary university hospital. The main question was "Can you describe your adaptation experience in the general ward as a nurse?" All interviews were recorded and transcribed, then analyzed using Colaizzi's method. Results: Four categories were derived from the analysis: 'difficulties from task adaptation by characteristics', 'limited nursing situation and circumstance as a male nurse', 'efforts to adapt at general nursing unit', and 'self-worth, and worry about something as a male nurse'. Conclusion: Male nurses had a difficulty adapting to work in wards due to lack of multi-tasking skills, as well as some social prejudice or negative views on male nurses. Establishing reasonable guidelines for male nurses in practice, promoting their responsibilities to patients, developing mentoring programs, and reassessing the policy of assigning male nurses to general wards are recommended to help in better adaptation.

• Journal of Ecology and Environment
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• 제34권2호
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• pp.175-191
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• 2011

Colonization patterns and community changes in benthic macroinvertebrates in the Cheonggye Stream, a functionally restored stream in downtown Seoul, Korea, were studied from November 2005 to November 2007. Benthic macroinvertebrates were quantitatively sampled 15 times from five sites in the stream section. Taxa richness (59 species in total) increased gradually over the first year, whereas the density revealed seasonal differences with significantly lower values in the winter season and after flood events. The benthic macroinvertebrate fauna may have drifted from the upstream reaches during floods and from the Han River, arrived aerially, or hitchhiked on artificially planted aquatic plants. Oligochaeta, Chironommidae, Psychodidae, and Hydropsychidae were identified as major community structure contributors in the stream. Swimmers and clingers colonized relatively earlier in the upper and middle reaches, whereas burrowers dominated particularly in the lower reaches. Collector-gatherers colonized at a relatively early period throughout the stream reaches, and collector-filterers, such as the net-spinning caddisfly (Cheumatopyche brevilineata), predominated in the upper and middle reaches after a 1-year time period. Cluster analyses and multi-response permutation procedures demonstrated that the Cheonggye Stream shares more similarities with the Jungnang Stream than with the Gapyeong Stream. Detrended correspondence analysis and nonmetric multidimensional scaling demonstrated that physical environmental factors (depth, current velocity, dissolved oxygen, and pH) as well as nutrients (total nitrogen and total phosphorous), water temperature, and conductivity could affect the distribution of benthic macroinvertebrates in the study streams.

• 한국의류학회지
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• 제39권6호
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• pp.885-898
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• 2015

This study develops scales to measure clothing consumption values for Korean male consumers. This study conducted qualitative and quantitative research to explore a new clothing consumption value among males as well as investigate empirically the measurement of clothing consumption values. In-depth interviews and focus group interviews were collected for qualitative research on 20 Korean men in their 20s-40s who had experience with 2 types of stores in Korean men's fashion. An analysis of qualitative data based on grounded theory approaches identified 6 factors and 15 items. For the empirical research, the questionnaire which consist of 9 factors and 46 items were developed by the results of grounded theory approaches and prior studies. Final measurement scales were based on 651 data used in exploratory factor analysis (EFA) and a confirmatory factor analysis (CFA). All subjects were in their 20s-40s. The result from CFA suggested 4 factors and 18 items with showing acceptable construct validity and discriminant validity. Therefore, this study confirmed that clothing consumption value for Korean male consumer consist of ostentatious and brand value, epistemic and possession value, conditional value, and reasonable value. These constructs will provide critical insight in understanding and segmenting Korean male consumers.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제19권4호
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• pp.7-18
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• 2013

Purpose: The aim of this paper is to reduce the stress and the disturbance occur in selective action of patient. This article will also help us to control spreading and reduce the order and bacteria produced by leprosy disease among the lepers. This will be achieved with the help of several variables and these variables help us on health benefits is 5S (Sort, Straighten, Shine, Standardize, Sustain) i.e. ratio of sectional morphology, lessor 90 degree angles, day light, universal design building and maximum ventilation. The replies from the questionnaire were collected based on varying levels of satisfaction and gloominess on the scale of 1-10. Methods: The multi-layer methodological framework for maximising the healing environment obtained from the observation of schemes and parameters of ANOVA: (Analysis Of Variance between five deciding factors) are. Firstly applied for the calculation of the patient's satisfaction for U.V light from sun on ECOTECT simulation, secondly the number of $90^{\circ}$ angle, along the corridors. Thirdly understanding the ways to represent people's perceptual structures and way finding with Space Syntax software. Fourthly the ratio of depth to height of the building typology and finally interviewing the subjects describing their special experiences based on scale value. The focus of this testing of human subjects was to receive data for the existence of image scheme in way-finding and to identify the mechanisms by which sun light impacts human (lepers) health. Results: AMPVA studies concluded that there is similarity between I and O plan as well as L and H plan whereas U plan was difference among the five selected architectural shapes. Implications: The purpose of this research is to show the effects of the I-type, L-type, C-type, U-type and O-type plan design, and to analyse the morphology for EBD (Evidence-Based Design) healing environment which is a universal design for Munghopir Karachi, in Pakistan.

• 한국콘텐츠학회논문지
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• 제12권3호
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• pp.268-275
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• 2012

본 연구는 다문화 가정 이주 여성의 구강건강행위, 치과 의료기관 이용, 식생활 실태와 구강건강 행위에 영향을 미치는 요인을 조사하여 이들을 위한 구강 인식개선 및 관리에 도움을 제공하고자 하였다. 그 결과 남편학력이 높은 국제결혼 이주여성이 올바른 잇솔질 행위를 하고 있었고, 필리핀 국적의 국제결혼 이주 여성들이 나머지 국적의 국제결혼 이주여성들에 비해 치과처치빈도가 높은 것으로 나타났고, 일본 국적의 국제결혼 이주여성들도 마찬가지로 치과처치빈도가 높았다. 또한 국제결혼 이주여성들의 나이와 월소득이 많을수록 치과처치빈도가 높았다. 따라서 결혼이주여성의 구강건강관리 개선을 위해서는 국가별, 소득별, 직업별로 사회문화 적응의 차이를 심도 깊게 분석한 정책이 마련되어야져야 한다.

• 한국수산과학회지
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• 제46권2호
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• pp.186-194
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• 2013

We compiled and analyzed long-term time-series data collected in Korea to evaluate changes in oceanographic conditions and marine ecosystems near Jeju Island ($33^{\circ}00^{\prime}-34^{\circ}00^{\prime}\;N$, $125^{\circ}30^{\prime}-127^{\circ}30^{\prime}\;E$) from 1981 to 2010. Environmental data included depth-specific time series of temperature and salinity that have been measured bimonthly since 1961 in water columns at 175 fixed stations along 22 oceanographic lines in Korean waters by the National Fisheries Research & Development Institute, and time series of estimated volume transport of the Tsushima Warm Current (TWC) and Korea Strait Bottom Cold Water (KSBCW) for the period from 1961 to 2008. We analyzed the species composition in terms of biomass of fish species caught by Korean fishing vessels in the waters near Jeju Island (1981-2010). Data were summarized and related to environmental changes using canonical correspondence analysis (CCA). The CCA detected major shifts in fish community structure between 1982 and 1983 and between 1990 and 1992; the dominant species were a filefish during 1981-1992 and chub mackerel from 1992 to 2007. CCA suggested that water temperature and salinity in the mixed layer and the volume transport of the TWC and the KSBCW were significantly related to the long-term changes in the fish community in the waters off Jeju Island. Fish community shifts seemed to be related to the well-established 1989 regime shift in the North Pacific. Further studies are required to elucidate the mechanisms driving climate change effects on the thermal windows and habitat ranges of commercial species to develop fisheries management plans based on reliable projections of long-term changes in the oceanographic conditions in waters off Jeju Island.