• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.4
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• pp.122-131
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• 2017

This study was a drone-utilized case study motivated by that drones can obtain sophisticated video image data previously not feasible. The dilemma zones on selected intersection approaches were identified and locations of drivers' decision making to stop or go at the onset of yellow were determined by analyzing drone video images. The gap between the drivers' decision making location and invisible stop/go border line provided by the yellow time interval was defined as "risky passing zone". To improve the dilemma zone safety problems, re-optimization of yellow time intervals and introduction of new pavement marking that can help drivers decision making on yellow indication are suggested.

• International Area Studies Review
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• v.14 no.1
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• pp.257-277
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• 2010

Rural tourism is considered one of the main components of travel today. This may explain the emerging interest in tourist behavior at rural sites. Nevertheless, it can be argued that research on tourists' motivation as well as segmentation for visiting rural sites is still in its infancy. The purpose of this study has three main objectives: (1)to adjust the motivations of rural tourism to the general motivations for all travelers and find the core factors for rural tourists. (2)to show the segmentation of korean rural tourists, and (3)to suggest the characteristics of rural tourists' typology. This paper was conducted through two studies: a literature review and a survey for empirical exploration of the ideas. The empirical data are extracted through convenience, and the valid questionnaires totaled to 828. The Frequency, Descriptive, Factor, Cluster, Discriminant, Cross-tabulation analysis were used for the data analysis. The results of analysis indicate that the rural tourists' motivation is consisted of 14 factors. the key elements play a major role in rural tourism. and the rural tourists' market was divided into 5 different groups. The results of this study will not only contributes to a better understanding of rural tourism due to clarification of tourist motivations but also have implication for the development and management of rural sites.

• Journal of dental hygiene science
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• v.10 no.5
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• pp.307-314
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• 2010

This study aimed to measure such features of emotional responses perceived by students as learning climate, department living stress, and perceived helplessness to analyze their effects on major satisfaction among students at the department of dental hygiene; to do this, a survey was conducted with 431 students, regardless of college year, who were at the department of dental hygiene in four colleges in Gyeonggi Province, Daejeon, and Chungcheong Province. An existing emotion scale which went through the generalization process was used to draw a multiple model in the combination form in order to collect emotional factors affecting college students' satisfaction with their major, which had existed as a hypothetical proposition, and make overall interpretation of relevance through the explainable, predictable modeling process by measuring emotional factors and phenomenal description of the level of general perception. The results showed that major satisfaction was very significantly affected by emotional features among students at the department of dental hygiene, which needs to be treated as an important factor to enhance expertise related to major learning and improve students' living.

• Proceedings of the Korean Vacuum Society Conference
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• 1999.07a
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• pp.174-174
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• 1999

Pt(001)의 깨끗한 표면은 재배열된 (5x20) 또는 (nxn) 구조를 갖는다. 이러한 재배열된 구조는 소？의 가스를 흡착에 대해서도 (1x1)구조로 다시 재배열되는 재배열인 쉽게 풀리는 준안정적 재배열 구조를 갖는 표면이다. Pt(100) 표면 위에 Ni과 같은 금속을 흡착시키는 경우도 동일하게 표면의 장력을 해소시켜 (1x1) 표면을 만든다. Pt와 Ni과 같은 덩어리 상태에서 Pt와 Ni가 질서있게 교차되어 배열되는 합금이 쉽게 이루어지는 물질들로 잘 알려져 있고, 이 합금은 Pt나 Ni와 동일한 규칙적인 fcc 구조를 갖는다. 따라서 Pt(100) 표면 위에 Ni를 흡착시키는 것은 Nm/Cu(100)과 같은 표면합금이나 Mn/Ag(1000에서 보이는 2층으로 된 표면 합금과 같은 표면 근방에 국한된 질서있는 표면 합금의 가능성이 있다. 또한 Ni/Pt(100)은 Ni과 Pt가 3대 1의 비로 조합될 때 나타나는 Ni3Pt의 층별구조인 표면에 Ni가 채워져 있고, 다음 층에 Ni와 Pt가 50%씩 질서 있게 섞여 있는 형태의 구조 즉 표면 밑 합금이 나타날 수 있는 가능성이 있는 물질계라는 점에서 관심을 갖게 한다. 본 연구는 LEED를 이용하여 Ni/Pt(100) 박막의 층별구조를 확인하고자 한다. PtNi 합금은 ATA(average t-matirx approximation)을 이용한 LEED 분석이 잘 적용되는 물질계로 알려져 있고, 본 연구는 ATA를 적용한 LEED I/V 분석을 통하여 Ni가 성장된 Pt(100) 표면의층별 농도비와 층별 구조를 구하고자 한다. 실험은 기본 압력이 3x10-11torr인 챔버에서 이루어졌으며, 증착시 압력은 5x10 torr이고, 증착은 열증발 방법을 이용하였다. Ni가 증착됨에 따라 (nxn) 재배열 표면에 기인한 extra spot들의 세기는 점차 감소하고 특정 증착량 이상에서부터 이 (nxn)의 spot들이 사라지고 깨끗한 (1x1) 패턴이 나타난다. 계속되는 증착량의 증가에 대해서도 이 (1x1) 형태는 유지되며, 표면의 질서에 따르는 c(2x20 패턴은 보이지 않았다. (1x1) LEED spot를 보임에도 불구하고 덩어리 절단 형태의 구조를 기반으로 한 LEED I/V 분석으로는 잘 맞출수 없었다. 이것은 Ni가 일정 이상 흡착된 경우 그 구조가 덩어리 절단 형태의 fcc(100) 구조와 벗어난 구조를 가지는 것으로 보인다.

• The Journal of the Korea Contents Association
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• v.12 no.9
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• pp.234-243
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• 2012

The purpose of this study was to estimate the prevalence of musculoskeletal symptoms and work-related factors of these symptoms in dental hygienists. The self-administered questionnaire was surveyed and collected from August 1-12 of 2011 targeting 210 dental hygienists Seoul, Gyeonggi, Daegu, Pohang. Except 5 people whose responses are not clear and who suffered accident, the analysis was made on 205 people. Data analysis was performed using the chi square test and multiple logistic regression analysis using the SPSS WIN(ver 18.0) program, RULA and, REBA. The overall Experience rate of musculoskeletal symptoms was 95.6% (196/205). The specific Experience rate of musculoskeletal symptoms for different regions of the body were as follows:The highest was shown 82.4% in Neck-shoulders(R), 78% in Neck, 69.8% in shoulders(R), 66.3%in Wrist(R). Therefore, Improvements of working environments in dental clinics are needed to prevent musculoskeletal disease development in dental hygienists.

• Journal of Korean society of Dental Hygiene
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• v.21 no.5
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• pp.535-543
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• 2021

Objectives: This study investigated the relationship between the Korean healthy eating index (KHEI) and periodontal disease in the Korean adult population. Methods: The data used in the analyses were obtained from the seventh Korean National Health and Nutrition Examination Survey (2016-2018). Data were analyzed by chi-square tests and t-test. Multiple regression analysis was also performed to assess the association between KHEI and periodontal disease. Statistical significance was set at p<0.05. Results: Multiple logistic regression analysis adjusted for socioeconomic variables showed that medical and health behavior variables were significantly related to the KHEI 1 (<63.7, odds ratio [OR]: 1.23, 95% confidence interval [CI]: 1.03-1.46), KHEI 2 (63.7-79.9, OR: 1.14, 95% CI: 0.97-1.34), and risk for periodontal disease. Conclusions: The results showed a significant association between the KHEI and periodontal disease in the Korean adult population.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1497-1507
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• 2016

The purpose of this study was to conduct importance and performance analysis of sanitation management in workers at small and medium foodservice industries using HACCP prerequisites. Questionnaires were distributed to 500 small and medium foodservice industry workers in Seoul Gyeonggi province, and a total of 458 responses were used for analysis. Factors with relatively low comparison degree were as follows. 'Handwashing and clean uniform of employee in the workplace', 'regular checking and managing of trapped vermin and rodents', 'checking stocked raw materials', 'recording and filing the results of improved food safety factors', and 'regular cleaning and sterilizing of monitoring tools' factors must be improved along with their performance levels through sanitation education. According to the IPA results, among the 15 HACCP prerequisite factors with high importance but low performance were '2. Regular checking and managing of trapped vermin and rodents', '4. Handwashing and clean uniform of employee in the workplace', '14. Preventing food cross-contamination'. Furthermore, the small and medium foodservice industry IPA with high importance but low performance were 'Regular checking and managing of trapped vermin and rodents', 'Handwashing and clean uniform of employee in the workplace', and 'Preventing food cross-contamination' for the small foodservice industry, along with 'Vermin and rodents control' and 'Recording and filing the results of improved food safety factors' for the medium foodservice industry. Thus, there is a need for reinforced hygiene education through case studies on actual food service establishments to fulfill sanitation guidelines and set amended guides for much-needed items for small and mid-sized food service.

• Journal of the Korean Orthopaedic Association
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• v.53 no.6
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• pp.490-497
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• 2018

Purpose: To evaluate the utility of ceramic-on-polyethylene articular bearing surface when cementless total hip arthroplasty is performed in patients older than 65 years through an analysis of the minimum five-year follow-up results using the ceramic femoral head and cross-linked polyethylene liner. Materials and Methods: From March 2010 to September 2012, 51 patients (56 hips) who were older than 65 years were enrolled in this retrospective study. The mean age at surgery was $70.9{\pm}5.1years$ old. A clinical assessment was analyzed using the Harris hip score. For the radiographic assessment, the cup inclination and anteversion, stem alignment, and wear amount were measured. The postoperative complications were also determined. Results: The mean Harris hip score was improved from preoperative 48 points to postoperative 87 points (p<0.05). The mean cup inclination was $40.9^{\circ}{\pm}6.4^{\circ}$ and the mean cup anteversion was $20.3^{\circ}{\pm}8.1^{\circ}$. The mean cup anteversion of the elevated liner-used group (16 cases) was $14.3^{\circ}{\pm}7.9^{\circ}$ and the mean cup anteversion of the neutral liner used group (40 cases) was $22.4^{\circ}{\pm}9.1^{\circ}$ (p<0.05). The mean stem alignment angle was $0^{\circ}$ (range, varus $4^{\circ}$-valgus $4^{\circ}$). The mean linear wear amount was $0.458{\pm}0.041mm$ and the average annual linear wear rate was $0.079{\pm}0.032mm/yr$. Six cases (10.7%) of intraoperative periprosthetic femoral fractures were encountered. Conclusion: Based on these results, the use of a ceramic-on-polyethylene articular bearing surface in elderly patients with cementless total hip arthroplasty is beneficial. On the other hand, careful effort is needed to prevent intraoperative periprosthetic femoral fractures.

• Journal of Nutrition and Health
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• v.53 no.3
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• pp.329-345
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• 2020

Purpose: This study examined the status of food allergy management and importance-performance analysis (IPA) between elementary, and middle and high school employees in school foodservice. Methods: The participants were employees in elementary (n = 171) and middle and high schools (n = 187) in the Jeonbuk area. The demographic characteristics, the status of food allergy management, food allergy education, and the importance and performance status were assessed using a self-administered questionnaire. Results: Approximately 55.0% of employees in elementary and 32.6% in middle and high schools recognized that the foods in menu tables induced allergies. Approximately 93.0% of employees in elementary and 85.0% in middle and high school thought that food allergy management was an important part of school foodservice because of the possibility of health emergencies. Elimination and replacement meals were provided more in middle and high schools than in elementary schools. Food allergy education from nutrition teachers had been given to 62.6% of employees in elementary and 50.3% in middle and high schools. To prevent food allergy accidents, 72.4% of employees in elementary schools and 65.2% in middle and high schools wanted more accurate information on students with food allergies. As a result of IPA, elementary, middle, and high school employees were aware of the importance and performed well: 'Strict control of allergy-inducing foods because of cross-contamination'. On the other hand, they were not aware of the importance and performed them insufficiently: 'Know how to use epinephrine to prepare for emergencies'. Conclusion: Therefore, it is necessary to improve the consciousness of nutrition teachers for the effective application of food allergy education, especially the recognition of allergy-inducing foods and emergency responsive ability.

• The Korean Journal of Applied Statistics
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• v.19 no.2
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• pp.319-330
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• 2006

A signal in real world usually composes of multiple signals having different scales of frequencies. For example sun-spot data is fluctuated over 11 year and 85 year. Economic data is supposed to be compound of seasonal component, cyclic component and long-term trend. Decomposition of the signal is one of the main topics in time series analysis. However when the signal is subject to nonstationarity, traditional time series analysis such as spectral analysis is not suitable. Huang et. at(1998) proposed data-adaptive method called empirical mode decomposition (EMD) . Due to its robustness to nonstationarity, EMD has been applied to various fields. Huang et. at, however, have not considered denoising when data is contaminated by error. In this paper we propose efficient denoising method utilizing cross-validation.