• 한국재료학회지
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• 제26권8호
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• pp.430-437
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• 2016

Aluminum oxide ($Al_2O_3$) thin films were grown by atomic layer deposition (ALD) using a new Al metalorganic precursor, dimethyl aluminum sec-butoxide ($C_{12}H_{30}Al_2O_2$), and water vapor ($H_2O$) as the reactant at deposition temperatures ranging from 150 to $300^{\circ}C$. The ALD process showed typical self-limited film growth with precursor and reactant pulsing time at $250^{\circ}C$; the growth rate was 0.095 nm/cycle, with no incubation cycle. This is relatively lower and more controllable than the growth rate in the typical $ALD-Al_2O_3$ process, which uses trimethyl aluminum (TMA) and shows a growth rate of 0.11 nm/cycle. The as-deposited $ALD-Al_2O_3$ film was amorphous; X-ray diffraction and transmission electron microscopy confirmed that its amorphous state was maintained even after annealing at $1000^{\circ}C$. The refractive index of the $ALD-Al_2O_3$ films ranged from 1.45 to 1.67; these values were dependent on the deposition temperature. X-ray photoelectron spectroscopy showed that the $ALD-Al_2O_3$ films deposited at $250^{\circ}C$ were stoichiometric, with no carbon impurity. The step coverage of the $ALD-Al_2O_3$ film was perfect, at approximately 100%, at the dual trench structure, with an aspect ratio of approximately 6.3 (top opening size of 40 nm). With capacitance-voltage measurements of the $Al/ALD-Al_2O_3/p-Si$ structure, the dielectric constant of the $ALD-Al_2O_3$ films deposited at $250^{\circ}C$ was determined to be ~8.1, with a leakage current density on the order of $10^{-8}A/cm^2$ at 1 V.

• 한국조경학회지
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• 제18권2호
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• pp.79-93
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• 1990

The purpose of this study is to establish better residential environment in APT. complex. In this study, the actual conditions of exterior space, user behavior and degree of satisfaction are investigated and analyzed on the 5 high-rise story APT complex in Taegu city. The results of this study were as follow ; The size and arrangement of organizational elemnnt to exterior space in APT. complex have been regulated by law and regulations as the buildings coverage and floor space index, but housinghold and accessibility to the racility will be simultaneously considered to raise Quality of the residential environoment. The main user behavior to exterior space in APT. complex was practical activity and the user behavior pattern by week and among APT. complex were found similiarly. In the ratio of use to exterior space in APT. Complex, that of high-rise residents were lower than that of lowrise residents. In the degree of satisfaction by property of variables to exterior environment In APT. comples, physical of buildings, social - psychologic, managerial economical, physical property of exterior space were estimated positively, but properly of facility were estimated negatively. The degee of satisfaction to exterior environment in APT. complex was highly Influenced by green space, site size. As a result of ractor analysis, the four factors were drawn out from exterior environment in APT. complex. and the factors that have an effect on the degree of residents' satisfaction by factorscore were found in the order of importance as fallow ; managemental, physical, environmental, organizalional factor. Therefore, devilopment of APT. complex should be considered in a view of environmental psychology according to physical organization for used in the future. It is recommended that this problems should be necessitated to be more deeply studies in the future.

• 대기
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• 제22권1호
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• pp.13-28
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• 2012

The $PM_{10}$ concentration data is useful for indentifying intensity and a transport way of Asian dust. However, it is difficult to identify them properly due to the limited spatial resolution and coverage. Therefore, a methodology to estimate $PM_{10}$ concentration using visibility data obtained from synoptic observation was developed. To derive the converting function, correlation between visibility and $PM_{10}$ concentration is investigated using visibility and $PM_{10}$ concentration data observed at 20 stations in Korea from 2005 to 2009. To minimize bias due to atmospheric moisture, data with higher relative humidity over a critical value were eliminated while deriving $PM_{10}$-visibility relationship. As a result, an exponentially decreasing function of visibility is obtained under the condition that relative humidity is less than 82%. Verification of the visibility converting function to $PM_{10}$ concentration was carried out for the dust cases in 2010. It was found that spatial distributions of $PM_{10}$ calculated by visibility are in good agreement with the observed $PM_{10}$ distribution, especially for the strong dust cases in 2010. And correlation between the derived and observed $PM_{10}$ concentration was 0.63. We applied the function to obtain distributions of $PM_{10}$ concentration over North Korea, in which concentration data are not available, and compared them with satellite derived dust index, IODI distributions for dust cases in 2010. It is shown that the visibility function estimates quite similar patterns of dust concentration with IODI image, which suggests that it can contribute for prediction by indentifying transport route of Asian dust.

• 한국콘텐츠학회논문지
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• 제10권7호
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• pp.449-458
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• 2010

이러닝 품질관리는 정보화 시대의 교육에 대한 책무성의 하나로 양적 팽창 보다는 질적 강화를 위한 기본 방침으로 이해되어야 한다. 이에 본 연구는 해외에서 이루어지고 있는 이러닝 품질관리 동향 조사를 통해 우리나라의 이러닝 품질관리가 어떤 형태로 진행되어야 하는지에 시사점을 제공하고자 하였다. 따라서 5개 국가 9개 기관의 이러닝 품질관리 현황, 영역 및 대상, 지표의 쓰임 등에 대해 알아보고, 5개국의 이러닝 품질관리 특징을 분석하였다. 분석결과, 이러닝을 위한 다양한 자원 확보, 국가 수준의 이러닝 품질관리 통합, 전문가 양성 그리고 품질관리 시스템에 대한 집중과 선택이라는 시사점을 찾을 수 있었다. 즉, 이러닝 품질관리는 업무의 측면이 아닌 교육의 질적 향상이라는 범 국가적 차원에서 접근할 필요가 있음을 알 수 있었다.

• Ocean and Polar Research
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• 제33권1호
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• pp.85-97
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• 2011

The tidal flats of Korea today have reduced by 40% in size compared to 1964. To manage this important habitat properly, development of well-organized and nationwide-applicable grading systems is required. There have been several assessment systems proposed previously in Korea, but they are critically flawed in that selected biological indicators are not adequate and grading criteria are obscure and arbitrary. We reviewed the indicators used in these previous evaluation systems (e.g., diversity indices, quantity and quality of benthic macrofauna, halophytes, water birds, etc.) and subsequently proposed new indicators and an improved grading scheme. For the quantitative assessment of macrobenthic community, biomass reflecting production and ecosystem function is recommended over density, which is much less discriminatory among habitats. Of biodiversity indices used, within-, between-habitat and regional biodiversity indices that accurately reflect sampling efforts are suggested. In addition, we proposed to include species rarity, ecosystem engineers, and the ecological quality index ISEP (Inverse function of Shannon-Wiener Evenness Proportion). As for halophytes, their low spatial coverage on benthic habitat suggests that their presence can be used as an ecological indicator of benthic habitat, regardless of their protective status. We stress the need to introduce 1) quantile approach for quantitative indicators (e.g., diversity, biomass, etc.) in relation to grading, 2) presence-absence approach for spatial or aggregate indicators (e.g., boundaries of halophytes and feeding ground of water birds) and 3) benthic habitat mapping that combines all of these indicators.

• 대한원격탐사학회지
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• 제30권4호
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• pp.505-510
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• 2014

NDVI는 기후변화 모니터링과 식생 변화 탐지 모니터링을 위한 주요한 지표이다. NDVI를 산출하기 전에 cloud masking, 대기보정과 같은 전처리 과정을 거침에도 불구하고 강수, 적설이나 구름의 영향이 완전히 제거되지 않아 NDVI가 현저히 낮게 관측되는 noise가 불규칙적으로 발생한다. 이러한 noise를 보정하기 위해서 국내외로 활발한 연구가 진행되고 있다. 기존의 다중 다항 회귀식을 이용한 방법에서는 과대추정이나 low peak를 잘 탐지하지 못하는 등 문제점이 나타나고 있으므로 보다 정확하게 noise를 보정하는 방법이 요구된다. 본 연구에서는 이동평균을 이용하여 noise를 보정하였고, 기존의 다중 다항 회귀식을 이용하여 산출한 NDVI 시계열과 비교를 해보았다. 그 결과 이동평균을 이용한 방법이 이전의 방법보다 NDVI noise를 잘 보정하는 것으로 보여진다.

• The Korean Journal of Pain
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• 제29권4호
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• pp.255-261
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• 2016

Background: Thoracic epidural anesthesia is frequently used to maintain intraoperative and postoperative analgesia. Frequently, 3 ml of local anesthetic is used as a test dose, or for intermittent epidural injection. We assessed the extent of the spread of 3 ml of contrast medium in the thoracic epidural space and attempted to identify any correlating factors affecting the epidurography. Methods: A total of 70 patients were enrolled in the study, and thoracic epidural catheterizations were performed under fluoroscopic guidance. Using 3 ml of contrast medium, epidurography was evaluated to confirm the number of spinal segments covered by the contrast medium. Correlation analysis was performed between patient characteristics (sex, age, body mass index, weight, height, and location of catheter tip) and the extent of the contrast spread. Results: The mean number of vertebral segments evaluated by contrast medium was $7.9{\pm}2.2$ using 3 ml of contrast medium. The contrast spread in the cranial direction showed more extensive distribution than that in the caudal direction, with statistical significance (P < 0.01). Patient height demonstrated a negative correlation with the extent of distribution of contrast medium (r = -0.311, P < 0.05). Conclusions: Thoracic epidurography using 3 ml of contrast medium results in coverage of a mean of $7.9{\pm}2.2$ spinal segments, with more extensive cranial spread, and patient height showed a weak negative correlation with the distribution of contrast medium.

• 대한방사선기술학회지:방사선기술과학
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• 제43권1호
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• pp.23-27
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• 2020

In South Korea, female individuals in their forties show a high rate of incidence, with approximately 13% of the patients being <40 years. This statistic is more than twice as high as that in Western countries. It is therefore necessary to identify the risk factors for breast cancer incidence by age and economic activity participation status. Women aged 30 to 59-whether breast cancer patients or those in the control group and having no breast cancer-were appraised from the sample cohort database. The data were analyzed using the statistical software R36.2. To identify the factors affecting breast cancer incidence, the degree of association was determined with HR and 95% CI by means of cox regression analysis. As for the socio-demographic variables, the older the individual, the higher the risk of breast cancer incidence becomes. As for the economic activity variables, those who were dependents (unemployed) and who had higher income (medium and high) were at higher risk of breast cancer incidence, which was statistically significant. The income-adjusted HR (model 1) for breast cancer development associated with the economic activity was 1.452 (95% CI, 1.19-1.77). The body mass index and alcohol intake-adjusted HR (model 2) was 1.431 (95% CI, 1.18-1.74). One needs to pay attention to policy plans regarding women's quality of life, as well as to the risk of breast cancer incidence by their economic activity. In other words, policies need to give post care, instead of focus on early detection and cancer treatment.

• 한국콘텐츠학회논문지
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• 제15권1호
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• pp.276-285
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• 2015

이 연구의 목적은 우리나라의 지역사회 건강관련 삶의 질에 영향을 미치는 지역사회 요인을 확인하기 위함이다. 2012년 단면연구이며, 국가통계포털의 209개의 시군구별 2차 자료를 사용하였다. 기본 틀은 International Council of Science(ICSU)에서 제시한 지역사회 건강결정요인을 바탕으로 구성하였고, 6가지 측면으로 분류하였다. 분석방법은 지역사회 EQ-5D지수와 지역사회 요인들에 다변량 회귀분석을 실시하였다. 분석결과로, 흡연율, "양호한" 주관적 건강수준 인식률, 상수 및 하수도 보급률 그리고 재정자립도가 EQ-5D에 통계적으로 유의하게 긍정적인 연관성이 있었다. 순인구이동률, 비만율, 필요서비스 미치료율 그리고 지역사회 유형이 EQ-5D에 통계적으로 유의하게 부정적인 연관성이 있었다. 이 연구는 지역사회 수준의 건강관련 삶의 질에 영향을 미치는 지역사회 요인들의 연관성을 확인했으며, 이것은 지역사회 건강 정책 개발에 유용한 증거를 제공할 수 있다.

• 한국언론정보학보
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• 제32권
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• pp.75-111
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• 2006

이 연구의 목적은 우리나라 언론 보도에서 정부 소스의 의제 속성에 의존하는 현상이 일어나고 있는가를 살펴본 다음, 정부의 중요정의자 기능과 관련하여 영향요인으로 거론되는 보도부정성, 보도이데올로기, 보도시기 등의 변수들이 가지는 영향력에 대해서 조사해 보는 것이다. 이러한 연구목적에 답하기 위해서 사회적인 논란을 불러왔던 행정수도 이전 관련 논의를 분석 케이스로 선택했으며, 이슈를 둘러싼 정부브리핑과 언론보도를 연구 텍스트로 선정하였다. 연구결과, 정부는 언론보도의 중요정의자 역할을 수행하는 것으로 나타났으며, 언론보도가 정부가 설정하는 이슈 속성의 테두리를 벗어나기 힘들다는 것을 보여주었다. 또한 언론의 부정성에도 불구하고 정부는 사안의 속성을 제한하는 중요정의자의 역할을 담당하고 있지만, 보도이데올로기나 사안의 갈등 시기 등의 영향권에서 자유롭지는 못하다는 것을 보여주고 있다.