• 한국대기환경학회지
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• 제18권2호
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• pp.113-126
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• 2002

This study was carried out to evaluate the temporal (daily, weekly, and seasonal) variations of volatile organic compounds (VOCs) concentrations at a road-side site in a heavy-traffic central area of Metropolitan Taegu. Ambient air sampling was undertaken continuously for 14 consecutive days in each of four seasons from the spring of 1999 to the winter of 2000. The VOC samples were collected using adsorbent tubes, and were determined by thermal desorption coupled with GC/MS analysis. A total of 10 aromatic VOCs of environmental concern were determined, including benzene, toluene, ethylbenzene, m＋p-xylenes, styrene, o-xylene, 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, and naphthalene. Among 10 target VOCs, the most abundant compounds appeared to be toluene (1.5 ∼ 102 ppb) and xylenes (0.1 ∼ 114 ppb), while benzene levels were in the range of 0.3 ∼6 ppb. It was found that the general trends of VOC levels were significantly dependent on traffic conditions at the sampling site since VOC concentrations were at their maximum during rush hours (AM 7∼9 and PM 7 ∼9). However, some VOCs such as toluene, xylenes, and ethylbenzene were likely to be affected by a number of unknown sources other than vehicle exhaust, being attributed to the use of paints, and/or the evaporation of solvents used nearby the sampling site. In some instances, extremely high concentrations were found for these compounds, which can not be explained solely by the impact of vehicle exhaust. The results of this study may be useful for estimating the relative importance of different emission sources in large urban areas. Finally, it was suggested that the median value might be more desirable than the arithmetic mean as a representative value for the VOC data group, since the cumulative probability distribution (n=658) does not follow the normal distribution pattern.

• 벤처창업연구
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• 제5권2호
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• pp.89-114
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• 2010

본 연구에서는 대학생의 성격 유형 및 직업 희망 유형에 따른 창업의지와의 관계를 연구 하고자 하였다. 창업의 정의와 유형, 창업의지에 관한 이론적 고찰, MBTI 성격유형에 관한 이론적 고찰을 통해 성격유형과 창업의지와의 관계 규명을 위한 모형설계를 통해 신뢰성 검증 및 회귀 분석을 실시하였다. 연구 결과 대학생의 성격유형은 창업의지에 유의한 음(-)의 영향을 미치는 것으로 나타났다. 성격유형 중 외향-내향 성격유형이 창업에 대한 관심도에는 (+)의 영향을 미치고, 창업 성공을 위한 생활태도에는 (+)의 영향을 미치지 않는 것으로 나타났다. 외향적인 성격유형을 가진 학생이 내향적인 성격유형을 가진 학생에 비해 창업에 대한 의지 즉, 창업에 대한 관심도 측면에 (+)의 영향을 미치는 것을 알 수 있다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권15호
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• pp.6711-6714
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• 2015

Background: Insomnia is a common condition in cancer patients. In spite of the high prevalence its associations have not been well studied. Existing data suggests that insomnia is related to depression and pain. However, the impact of ongoing chemotherapy on sleep is not investigated. Aim: To study the relationship between insomnia and chemotherapy after analysing confounding variables. Materials and Methods: Consecutive patients who visited New England Oncology Clinic in Tamworth were recruited. Insomnia was assessed with the Bergen insomnia scale. The Montgomery Asberg Depression rating scale was used to measure depression. Pain was assessed with the Brief Pain inventory. Chronic medical conditions, type of cancer, side effects to chemotherapy, role of steroids and other drugs were studied as confounders. Results: A total of 56 patients participated in the study. Age ranged from 33 to 83 years (mean: 63.6, SD=10.97). There were 29 men and 27 women. 42 patients received at least one form of chemotherapy and 15 were receiving radiotherapy at the time of assessment. Mean insomnia score was significantly higher in those receiving chemotherapy than in those without chemotherapy (8.92 vs 17.2, two tailed p=0.005, 95% CI=2.63-13.71). There was no significant variation in insomnia scores in terms of chronic medical condition, type of cancer, psychiatric history, use of steroids or adverse effects of chemotherapy. However, total insomnia score was correlated with depression rating score (Pearson correlation, r=0.39, p=0.003) and magnitude of pain (r=0.37, p=0.006). On regression analysis only pain was found to be predictive of insomnia. Conclusions: Insomnia in patients with cancer is found to be associated with concurrent chemotherapy and correlated with degree of depression and pain. Identifying factors related to insomnia in cancer population has implications in its management and patient education.

• 한국인터넷방송통신학회논문지
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• 제15권2호
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• pp.39-44
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• 2015

클라우드 서비스의 특징으로 인한 보안위협이 상존함에도 불구하고 클라우드 서비스의 장점의 급부상 등으로 국내 클라우드 서비스는 중장기적으로 확산될 전망이다. 그동안 많은 연구에서는 클라우드 서비스 활성화의 저해요인으로 주로 보안 위협과 품질을 지적하였다. 이용자 측면에서 클라우드 서비스의 품질 중요성이 강조되고 있는 가운데, 품질항목들이 클라우드 서비스 이용자의 만족도에 어느 정도 중요한 영향을 미치는지에 대한 고찰은 없었다. 따라서 본 연구에서는 클라우드 서비스를 사용 경험이 있는 이용자 대상으로 품질 중요도 인식에 대한 설문 분석을 하였다. 분석 결과 'SLA 보장'이 '보안 성능' 보다 이용자 만족도에 더 중요한 영향을 주고 있는 것으로 나타났다. 본 연구결과는 향후 클라우드 서비스를 제공하는 기업들의 '이용자 중심의 품질 전략 수립'에 도움이 될 것으로 기대된다.

• 성인간호학회지
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• 제12권4호
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• pp.497-506
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• 2000

The purpose of this phenomenological study was to explore and describe the experience of people with HIV/AIDS. Three men and three women with HIV/AIDS participated in the study. They were asked open-ended and descriptive questions in order for them to talk about their experience in their own terms. Interviews were audiotaped and transcribed to maintain data integrity and to reduce perceptual bias. The transcripts were analyzed by the Colaizzi method. Member checks from the participants were used to validate the emergent themes. Seven themes emerged from the analysis. 1. People with HIV/AIDS have a strong impact and emotional reaction when receiving positive HIV test results. 2. All people with HIV/AIDS attempt to conceal HIV infection because of fear of stigma or rejection. 3. After the initial brief traumatic reaction to HIV/AIDS diagnosis, all participants feel lonely because they had no one to express or share their own experiences. 4. People with HIV/AIDS reflect on their life, think about the death and dying process and they become depressed. 5. Most participants feel that the family members who know his/her diagnosis are a big source of support. 6. According to the normativeness of infection route of HIV, the degree of guilty feeling differs among participants. 7. Although all participants think medication is a lifeline, the adherence to medication is not maintained because of side effects, denial and concealment of HIV/AIDS. The results of this study may help nurses and other health care workers to implement more efficient nursing strategies for people with HIV/AIDS by more deeply understanding their experience.

• 대한지리학회지
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• 제38권6호
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• pp.863-886
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• 2003

인터넷의 확산에 따라 인터넷 경제가 도래하면서, 인터넷 경제의 핵심적 역할을 하는 인터넷 산업은 상당히 빠른 속도로 성장하고 있다. 우리나라도 이미 인터넷 경제에 들어섰으며, 인터넷 관련 산업들이 새롭게 등장하고 있다. 이러한 인터넷 산업의 성장은 공간경제구조에 상당한 영향을 미치고 있으나. 아직까지 인터넷 산업에 대한 지리학적 연구는 매우 미흡한 실정이다. 본 연구에서는 인터넷 산업의 성장을 가져온 주요 동인을 수요와 공급적인 측면에서 살펴 본 후에, 인터넷 산업의 분류체계를 구축하는 방법을 모색하고. 그 방법에 따라서 인터넷 산업에 대한 데이터베이스를 구축하였다. 이렇게 구축된 데이터베이스를 토대로 하여 인터넷 산업의 공간적 분포 특성을 분석하였다. 급성장하고 있는 인터넷 산업은 서울로 집중하는 추세를 보이고 있으며, 서울내에서는 강남지역으로의 집적 현상이 두드러지게 나타나고 있다. 인터넷 산업의 업종간 상호의존적이며 보완적인 특성으로 인해 서울은 누적적ㆍ순환적인 이점을 누리면서 수위성을 높여가고 있는 것으로 나타났다.

• 한국해양공학회지
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• 제30권5호
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• pp.400-404
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• 2016

This paper presents experimental results for the vibration characteristics of the small unmanned underwater vehicle (UUV) OPKO 300, which was designed and manufactured by Daewoo ship and Marine Engineering Ltd. The autonomy of UUVs has led to an increase in their use in scientific, military, and commercial areas because their autonomy makes it possible for UUVs to be utilized instead of humans in hazardous missions such as mine countermeasure missions (MCM). Since it is impossible to use devices based on electromagnetic waves to gather information in an underwater environment, only sonar systems, which use sound waves, can be used in underwater environments, and their performance can strongly affect the autonomy of a UUV. Since a thruster system, which combines a motor and propeller in a single structure, is widely used as the propulsion system of a UUV and is mounted on the outside of a UUV’s stern, it can generate vibration, which can be transferred throughout the shell of the UUV from its stern to its bow. The transferred vibration can affect the performance of various sonar systems such as side-scan sonar or forward-looking sonar. Therefore, it is necessary to estimate the effect of the transferred vibration of the UUV on the sonar systems. Even if various numerical methods were used to analyze the vibration problem of a UUV, it would be hard to predict the vibration phenomena of a UUV at the initial design stage. In this work, an experimental study using OKPO 300 and an impact hammer was carried out to analyze the vibration feature of a small real UUV in the air. The frequency response function of the vibration based on the experimental results is presented.

• 해양환경안전학회지
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• 제25권5호
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• pp.601-608
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• 2019

본 연구에서는 선수 돌출의 반전형 선수 형상을 가진 고속 쌍동선의 선체부착 부가물에 의한 주행성능 영향에 대하여 수치해석과 회류수조 모형시험을 통하여 비교분석하였다. 반전형 선수 형상은 재래식 선수 형상보다 선수 발산파 파정의 생성위치를 선미방향으로 이동시켜 개선된 조파형상을 보이며, 저항 및 안정된 항주자세에 효과적임을 보였다(Kim et al., 2019). 본 연구에서의 반전형 선수 내측에 부착된 핀과 선미단 인터셉터(Interceptor)에 의한 파형과 항주자세 변화 등 주행성능에 대한 모형시험 결과에서는, 1) 반전형 선수의 Trim 특성 2) Fin에 의한 내측 파의 중첩 개선 3) Fin과 Interceptor에 의한 자세제어는 두 선체 연결갑판(Wetdeck) 충격을 줄이는데 효과적인 것으로 판단된다.

• Asia-Pacific Journal of Atmospheric Sciences
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• 제54권4호
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• pp.545-561
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• 2018

Over the North East Asia, extreme anomalous precipitation were observed in 2013 and 2014. During 2013 summer the precipitation was found to be higher (two standard deviation) than the climatological mean of the region; whereas during 2014, which was a borderline El Ni?o year, precipitation was found to be lower (one standard deviation). To understand the differences of these two anomalous years the Global/Regional Integrated Model system (GRIMs) has been used. The study found that low landsurface temperature and high sea-surface temperature over ocean caused a smaller land-sea contrast of surface temperature between East Asia and North West Pacific Ocean in 2014, which could have caused an eastward shift of mean monsoon circulation in that year compared to the circulation in 2013. Due to a change in the lower level circulation and wind field over East Asia the evaporation and moisture transport patterns became very different in those two years. In 2013, this study found high latent heat flux over Eastern China, which implies an increased surface evaporation over that region, and the moisture transported to the north by the mean monsoon circulation; whereas, there was no correlated transport of moisture to the North East Asia during 2014. The precipitable water over North East Asia has a stronger correlation with the latent heat flux over southern land region than that from Ocean region in the eastern side in both the years. A new approach is proposed to estimate the sub-grid scale hydrometeors from GRIMs, overestimated in the existing model.

• 정보화정책
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• 제27권4호
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• pp.47-66
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• 2020

머신러닝과 딥러닝 등 인공지능 기술의 급속한 발전은 행정-정책 분야에도 영향을 확대하고 있다. 이 논문은 데이터분석과 알고리즘의 발전으로 자동화된 구성과 운용을 설계하는 인공지능 시대의 정책의사결정에 관한 탐색적 연구이다. 이 연구의 의의는 정책의사결정에서의 주요 연구 중 하나인 정책 문제의 문제구조화를 기반으로 하여, 문제정의가 잘 구조화된 정도에 따른 유형으로 이론적 틀을 구성하여 성공과 실패 사례를 구분하고 분석해서 시사점을 도출하였다. 즉 문제구조화가 어려운 유형일수록 인공지능을 활용한 의사결정의 실패 혹은 부작용의 우려가 크다는 것이다. 또한 알고리즘의 중립성여부에 대한 우려도 제시하였다. 정책적 제언으로는 우리나라 인공지능 추진체계구축 시 기술적 측면과 사회적 측면의 전문가들이 전문적으로 역할을 하는 소위원회를 병렬적으로 두고 이 소위원회들이 종합적, 융합적으로도 작동할 수 있는 운영의 묘를 발휘하는 거버넌스 추진체계 구축이 필요함을 제시하고 있다.