• Investigative Magnetic Resonance Imaging
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• 제4권2호
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• pp.120-127
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• 2000

최근에 해상도의 손실없이 신호대잡음비를 개선시킬 수 있는 적응 템플릿 필터링이 제안되었다. 적응 템플릿 필터링은 다중 템플릿들 중에서 현재 복셀의 주변 구조와 가장 잘 매칭이 되는 템플릿을 선택하여 적응필터 링을 적용하는 방법이다. 적응 템플릿 필터링을 자기공명영상에 적용할때 기존의 필터링 방법들에 비하여 향상된 결과를 얻을 수 있으나, $T_1$ 영상과 같이 비교적 작은 동적 범위를 가진 영상에서는 에지에서 계단모양의 artifact가 발견되곤 한다. 이것은 자기 공명영상에서 복셀의 부분적인 볼륨 효과에 기인하는 것으로 여러 조직의 성분을 포함하고 있는 경계면의 복셀들에 적응 템플릿 필터링이 적용될 경우 다중성분을 가진 복셀들의 그레이레벨이 인접한 단일성분의 그레이레벨 값에 가까워져 에지가 강조되기 때문이다 본 논문에서는 다중 성분을 갖는 복셀들을 선별하여 이들에 대해서는 가장 큰 크기의 템플릿을 할당함으로써 artifact를 제거하는 방법을 제안하였다. 제안한 방법을 $T_1$ 자기공명영상과 팬텀 영상에 적용한 결과 에지 artifact가 사라지는 것을 확인할 수 있었으며, 최대 신호대잡음비 면에서도 향상된 결과를 얻을 수 있었다.

• 한국재료학회지
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• 제15권6호
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• pp.361-369
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• 2005

InP(100) crystal surface was irradiated by ion beams with low energy $(180\~225\;eV)$ and high flux $(\~10^{15}/cm^2/s)$, Self-organization process induced by ion beam was investigated by examining nano structures formed during ion beam sputtering. As an ion source, an electrostatic closed electron Hall drift thruster with a broad beam size was used. While the incident angle $(\theta)$, ion flux (J), and ion fluence $(\phi)$ were changed and InP crystal was rotated, cone-like, ripple, and anistropic nanostrucuture formed on the surface were analyzed by an atomic force microscope. The wavelength of the ripple is about 40 nm smaller than ever reported values and depends on the ion flux as $\lambda{\propto}J^{-1/2}$, which is coincident with the B-H model. As the incident angle is varied, the root mean square of the surface roughness slightly increases up to the critical angle but suddenly decreases due to the decrease of sputtering yield. By the rotation of the sample, the formation of nano dots with the size of $95\~260\;nm$ is clearly observed.

• Journal of Information Science Theory and Practice
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• 제6권2호
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• pp.46-61
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• 2018

The mobile social networking application Instagram is a well-known platform for sharing photos and videos. Since it is folksonomy-oriented, it provides the possibility for image indexing and knowledge representation through the assignment of hashtags to posted content. The purpose of this study is to analyze how Instagram users tag their pictures regarding different kinds of picture and hashtag categories. For such a content analysis, a distinction is made between Food, Pets, Selfies, Friends, Activity, Art, Fashion, Quotes (captioned photos), Landscape, and Architecture image categories as well as Content-relatedness (ofness, aboutness, and iconology), Emotiveness, Isness, Performativeness, Fakeness, "Insta"-Tags, and Sentences as hashtag categories. Altogether, 14,649 hashtags of 1,000 Instagram images were intellectually analyzed (100 pictures for each image category). Research questions are stated as follows: RQ1: Are there any differences in relative frequencies of hashtags in the picture categories? On average the number of hashtags per picture is 15. Lowest average values received the categories Selfie (average 10.9 tags per picture) and Friends (average 11.7 tags per picture); for highest, the categories Pet (average 18.6 tags), Fashion (average 17.6 tags), and Landscape (average 16.8 tags). RQ2: Given a picture category, what is the distribution of hashtag categories; and given a hashtag category, what is the distribution of picture categories? 60.20% of all hashtags were classified into the category Content-relatedness. Categories Emotiveness (about 4.38%) and Sentences (0.99%) were less often frequent. RQ3: Is there any association between image categories and hashtag categories? A statistically significant association between hashtag categories and image categories on Instagram exists, as a chi-square test of independence shows. This study enables a first broad overview on the tagging behavior of Instagram users and is not limited to a specific hashtag or picture motive, like previous studies.

• 한국치위생학회지
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• 제9권3호
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• pp.403-414
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• 2009

Objectives : This research aimed at investigating middle school students' knowledge and behavior of oral hygiene according to the knowledge level of parents on this ground, provide basic data for establishing a more effective school and home oral hygiene education program for students. Methods : Students were selected from four secondary schools in J city by convenience sampling, which is non probability sampling; then, the final analysis was performed on 272 self-administered questionnaires. For statistical analysis, SPSS 10.0 for Windows was used to carry out frequency analysis and chi-square test at the 0.05 significance level in determining statistical significance. Results : 1. 50.0% had periodontal disease caused by 'weak periodontal', in the case of the father of academic ability was middle school graduated. 2. Showed lowly what is behavior prevention as regularly oral examination for the oral health, in the case of the parents's academic ability was low(in the case of the mother's academic ability was middle school graduated, 34.5% received regular oral examination every three months). 3. In the case of, the father and mother of academic ability was middle school graduated showed 50%, 44.8% about the teeth never important in the life. 4. In the case of, the father and mother of academic ability was middle school graduated showed 37.5%, 31.0% about time for the tooth brushing is under 1 minute per one time. Conclusions : It's very important for middle school student's oral health that the oral health education and oral hygiene attitude in their home. especially middle school student's attitude was controlled by parents' knowledge level. This like basic data will be useful in establishing program of school oral health and individual oral hygiene attitude in their home.

• 생태와환경
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• 제41권2호
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• pp.247-263
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• 2008

A two-dimensional (2D) reservoir hydrodynamics and water quality model, CE-QUAL-W2, is employed to simulate the hydrothermal behavior and density current regime in Andong Reservoir. Observed data used for model forcing and calibration includes: surface water level, water temperature, dissolved oxygen and suspended solids concentration. The model was calibrated to the year of 2003 and verified with continuous run from 2000 till 2004. Without major adjustments, the model accurately simulated surface water levels including the events of large storm. Deep-water reservoirs, like Andong Reservoir, located in the Asian Monsoon region begin to stratify in summer and overturn in fall. This mixing pattern as well as the descending thermocline, onset and duration of stratification and timing of turnover phenomenon were well reproduced by the Andong Model. The temperature field and distinct thermocline are simulated to within $2^{\circ}C$ of observed data. The model performed well in simulating not only the dissolved oxygen profiles but also the metalimnetic dissolved minima phenomenon, a common1y occurring phenomenon in deep reservoirs of temperate regions. The Root Mean Square Error (RMSE) values of model calibration for surface water elevation, temperature and dissolved oxygen were 0.0095 m, $1.82^{\circ}C$, and $1.13\;mg\;L^{-1}$, respectively. The turbid storm runoff, during the summer monsoon, formed an intermediate layer of about 15 m thickness, moved along the metalimnion until being finally discharged from the dam. This mode of transport of density current, a common characteristic of various other large reservoirs in the Asian summer monsoon region, was well tracked by the model.

• 한국방재학회 논문집
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• 제9권6호
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• pp.69-75
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• 2009

본 연구의 목적은 2006년 평창 수해를 겪으면서 마을 대표인 이장이 수행한 역할과 업무 스트레스를 조사하는데 있다. 전화 설문과 인터뷰에 기반한 연구 결과를 보면, 공식적으로 이장의 역할은 행정기관과 마을 주민을 연결하는 역할을 수행하는 것으로 제한되어 있으나, 실제 재난 과정에서 이장은 주민들을 대피시키고, 자원을 배분하고, 복구를 지휘하는데 있어서 중요한 역할을 수행하였음을 알 수 있다. 게다가 예기치 않은 과도한 부담으로 인하여 상당수의 이장들은 심각한 업무 스트레스를 겪은 것으로 밝혀졌다; 60 퍼센트의 이장들은 이장 업무를 그만두고 싶었고, 약 4분의 3에 해당하는 이장들은 전화 벨이 울릴 때마다 놀랐거나, 몸무게 변화가 있었다고 응답하였다. 또한 카이 제곱 검정 결과에 의하면, 사전 교육, 마을 주민들로부터 욕을 들었는가의 여부, 재난 피해는 업무 스트레스와 통계적으로 의미있게 연관되어 있는 것으로 밝혀졌다. 이러한 결과는 농촌 지역의 재난 관리 계획을 수립하는데 있어서 명령 통제 모델보다는 발현적 인적 자원 모델이 더 효과적인 접근이 될 수 있음을 제시한다.

• Nutrition Research and Practice
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• 제11권2호
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• pp.130-138
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• 2017

BACKGROUND/OBJECTIVES: Low consumption of fruit and vegetable is frequently viewed as an important contributor to obesity risk. With increasing childhood obesity and relatively low fruit and vegetable consumption among Thai children, there is a need to identify the determinants of the intake to promote fruit and vegetable consumption effectively. SUBJECTS/METHODS: This cross-sectional study was conducted at two conveniently selected primary schools in Nakhon Pathom. A total of 609 students (grade 4-6) completed questionnaires on personal and environmental factors. Adequate fruit and vegetable intakes were defined as a minimum of three servings of fruit or vegetable daily, and adequate total intake as at least 6 serves of fruit and vegetable daily. Data were analyzed using descriptive statistics, the chi-square test, and multiple logistic regression. RESULTS: The proportion of children with a sufficient fruit and/or vegetable intakes was low. Covariates of child's personal and environmental factors showed significant associations with sufficient intakes of fruit and/or vegetable (P < 0.05). Logistic regression analyses showed that the following factors were positively related to sufficient intake of vegetable; lower grade, a positive attitude toward vegetable, and fruit availability at home; and that greater maternal education, a positive child's attitude toward vegetable, and fruit availability at home were significantly associated with sufficient consumption of fruits and total fruit and vegetable intake. CONCLUSIONS: The present study showed that personal factors like attitude toward vegetables and socio-environmental factors, such as, greater availability of fruits were significantly associated with sufficient fruit and vegetable consumption. The importance of environmental and personal factors to successful nutrition highlights the importance of involving parents and schools.

• 한국자동차공학회논문집
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• 제19권3호
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• pp.83-89
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• 2011

Diesel engines can produce higher fuel efficiency and lower $CO_2$ emission, they are subject to ever more stringent emission regulation. However, there are two major emission concerns fo diesel engines like such as particulate matter (PM) and nitrogen oxides (NOx). Moreover, it is not easy to satisfy the regulations on the emission of NOx and PM, which are getting more strengthened. One of the solutions is to apply the new combustion concept using multistage injection such as HCCI and PCCI. The other solution is to apply after-treatment systems. For example, lean NOx trap catalyst, Urea-SCR and others have various advantages and disadvantages Especially, Urea-SCR system have advantages such as a high conversion efficiency and a wide operation conditions. Hence the key factor to implementation of Urea-SCR technology, good mixing of urea(Ammonia) and gas, reducing Ammonia slip. Urea mixer components are required to facilitate evaporation and mixing because the liquid state of urea poses significant barriers for evaporation, and the distance to mixer is the most critical that affect mixer performance. In this study, to find out the distance from injector to mixer and simulation factor, a laser diagnostics and high speed camera are used to analyze urea injector spray characteristics and to present a distribution of urea solution in transparent manifold In addition, Droplet Uniformity Index is calculated from the acquired images by using image processing method to clarify the distribution of spray.

• 대한약침학회지
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• 제21권3호
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• pp.185-194
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• 2018

Objectives: Vaginal Candidiasis with an approximate prevalence of 30% is the second cause of vaginal infections. Antifungal azole is the first treatment for Vaginal Candidiasis; however, some side effects have been reported for this chemical medicine. Based on the antifungal activity of Inner Stratum of Quercus Brantii (Q. Brantii), the aim of our study was to compare the effects of vaginal douche of Q. Brantii extract and clotrimazole on vaginal candidiasis symptoms before and after the treatments, in women. Methods: 89 non-pregnant women with positive KOH test which is capable of identifying the presence of hyphae and mycelium by adding KOH (10%), and a positive vaginal candidiasis culture were randomly divided into two experimental groups, using permuted block randomization method. One group received clotrimazole vaginal cream (1%) and the other group received vaginal douche of Q. Brantii extract. Groups were treated for 7 days and KOH tests and cultures were evaluated again. Data were analyzed via chi-square and independent t-test, using SPSS software. Results: According to the results, there were no significant differences between experimental groups for demographic characteristics like age (p=0.403), BMI (p=0.911), educational levels (p=0.862) and contraceptive methods (p=0.702). Moreover, significant differences were seen in vaginal discharge between the groups after the treatments (P=0.043). Conclusion: The results suggested that the therapeutic effect of vaginal douche of Q. Brantii extract was approximately similar to that of clotrimazole vaginal cream.

• 한국언론정보학보
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• 제40권
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• pp.221-248
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• 2007

본 연구는 다양한 영화 창구별 소비 특성 및 후속 시장에서의 소비 특성을 살펴보기 위한 것이다. 본 연구의 주요 분석 결과는 다음과 같다. 첫째, 응답자에게 영화 소비 선호 창구를 질문한 결과, 극장, 비디오, DVD, 지상파TV, 케이블TV, 인터넷 등을 포함하는 6개 영화 소비 매체별 조합이 48개로 나타났다. 극장은 자체만의 창구 시장 점유율은 33.5% 정도로 추정되지만, 비디오와 DVD, 지상파TV, 케이블TV, 인터넷 등의 후속 창구와 연계될 때에는 총 64.50%까지 시장이 확대되는 것으로 나타났다. 이는 영화가 다른 후속 창구와의 의존도가 높다는 것을 의미하기도 한다. 둘째, 인구통계학적 특성별 영화 소비 창구 특성을 살펴보았다. 연령별로 영화 소비 창구 조합의 특성을 살펴보면, 40대 응답자들은 극장이 차지하는 비중이 가장 높게 나타난 반면, 10대 응답자들은 극장 비중이 낮게 나타났다. 학력별로 살펴보면, 대졸 이상 응답자들이 극장을 영화 소비 창구로 선택하는 비율은 34.3%인 반면, 고졸 이하 응답자들은 13.1%로 나타났다. 소득별로 영화 소비 창구 조합의 특성을 살펴보면, 400만 원 이상의 고소득 계층에 속하는 응답자들은 극장 비중이 48.9%로 매우 높은 반면, 기타 다른 시장이 차지하는 비중은 낮은 것으로 나타났다. 100만 원 미만의 소득을 갖는 응답자들은 극장 및 후속시장 2개의 비중이 16.8%로 다른 집단에 비해 높은 것으로 나타났다. 영화 소비량별로 영화 소비 창구 조합의 특성을 살펴보면, 영화 소비량이 증가할수록 극장 의존도가 감소하는 것으로 나타났다. 셋째, 극장에서는 일차 소비만으로 더 이상 영화를 소비하지 않는 응답자 비율이 47.7%로 나타난 반면, 개별 후속 시장에서는 그 비중이 0.8%로 나타났다. 이는 후속 시장에서 영화를 소비한 응답자들은 다른 창구에서도 계속적으로 영화에 접근한다는 것을 의미한다.