• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.61.1-61.1
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• 2011

풍력 터빈은 복잡한 바람 조건에 노출되어 운용 되는 시스템으로서 경제성과 신뢰성을 확보하기 위해서는 이러한 조건하에서 시스템에 작용하는 정확한 공력 하중 예측이 필요하다. 여러 조건 중에서도 요에러는 풍향이 수시로 바뀌기 때문에 피할 수 없는 비정상 유동 중에 하나이다. 본 연구에서는 이러한 요에러 발생시 공력 하중예측을 적절히 예측하기 위해서 와류 격자 기법을 기반으로 하는 비선형 와류 보정기법을 적용하였다. 비선형 와류 보정기법은 실속 이후의 공력 예측을 위해 기지의 공력 테이블을 이용하는 방법으로서 실속 이후의 공력 테이블 값의 양력과 와류 격자 기법에서의 양력 값이 일치하도록 순환(circulation)을 분포시키는 기법이다. 또한 요에러시에 발생할 수 있는 동적 실속을 계산하기 위해 Beddoes-Leishmen 동적 실속 모델을 비선형 와류 보정 기법에 적용하는 연구를 수행하였다. 요에러시 공력 하중 예측에 관한 수치해석 기법 연구의 적절성을 알아보기 위해 NREL-Phase VI Rotor 실험 결과와 비교 하였다. 그 결과 기존의 여타의 기법들과 비교하여 본 연구에서 제안한 기법의 적절성을 확인 할 수 있었다. 앞으로 본 연구를 바탕으로 다양한 비정상 공력 조건에 대한 풍력 블레이드의 공력 하중 해석에 대해 수행할 계획이다.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.6
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• pp.73-84
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• 2010

The urban representative landscapes play a leading role in establishing city identity via a symbol of the city and a mediator to make the city all the more worthy of being peculiarized. The study aims at evaluating the perceptive factors in the representative landscapes around the metropolitan Seoul derived from the preliminary researches through questionnaire surveying, in an attempt to analyze their characteristics by type and reason, while further proposing progressive management plans. This study was mostly focused on the visibility factor, activity factor, aesthetic factor and cultural factor influencing on the cognition of urban representative landscapes. The important findings discovered in this research are as follows. First, it was found that people were being interested more on the cultural factors and the activity factors these days rather than visibility factors in the cognition of urban representative landscapes. Second, it was found that the priority rank of urban representative landscapes revealed in this study based on the total account of more diverse perceptive factors, showed so much alteration compared to the previous researches focused mostly upon the visual image.

• Journal of Hospice and Palliative Care
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• v.9 no.1
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• pp.11-16
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• 2006

Purpose: This study is aimed to confirm nurse's attitudes and to investigate the factor analysis on organ donation in brain dead donors. Methods: This survey were collected from 198 nurses in three university hospitals and four general hospitals in B city with questionnaires developed by the author. The consent for this research was obtained from nursing managers, head nurses, and staff nurses after explaining the purpose of this research. Results: In questionnaires, 45 items about attitudes were included and positive and negative attitude were analyzed. The contents of factors are 'legal permission of brain death', 'one's will of organ donation at the brain death', 'need for educational program about brain dead during college curriculum', 'organ donation is good presents for others', 'connection with professional institutes', 'necessity of brain death', 'convenient to control of brain death' and 'the goods for organ transplantation in brain dead donors' as positive attitudes. Meanwhile, 'contrast to certain religion and dignity to life', 'negative dangers on brain dead permission', 'unbelief to the medical teams', 'burdens to ask organ donation to brain deads/families' and 'economical compensation' are factors as negative attitudes about organ donation in brain dead. The total mean point score of positive attitudes about organ donation in brain dead donors was $3.753{\pm}3.398$. The total mean point score of negative attitudes about organ donation in brain dead donors was $2.915{\pm}0.472$. Conclusion: The results of this study may be of help for the nurses who concern organ sharing and make effective interventions and educations to facilitate the decision making process for organ donation in brain dead donors or families.

• The Optical Journal
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• s.169
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• pp.47-51
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• 2017

• The Korean Journal of Applied Statistics
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• v.19 no.3
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• pp.587-598
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• 2006

The number of variables exceeds the number of samples in microarray data. We propose a nonparametric local linear logistic classification procedure using orthogonal components for classifying high-dimensional microarray data. The proposed method is based on the local likelihood and can be applied to multi-class classification. We applied the local linear logistic classification method using PCA, PLS, and factor analysis components as new features to Leukemia data and colon data, and compare the performance of the proposed method with the conventional statistical classification procedures. The proposed method outperforms the conventional ones for each component, and PLS has shown best performance when it is embedded in the proposed method among the three orthogonal components.

• Science of Emotion and Sensibility
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• v.22 no.3
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• pp.47-54
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• 2019

We examined previous studies of the correlation analysis of heart rate variability as a method to reduce the stress caused by outside noise during driving, and we investigated whether there are electrocardiographic changes when drivers play music, which provides a stable sound source amid the noise. Because the number of cars increases every year, drivers and passengers show an increase in stress caused by outside noise. The stress from outside noise while a person is driving can cause several disorders, such as anxiety, immunosuppression, depression, and heart disease. Subjects in this study operated a vehicle simulator to reduce the stress from outside noise and were given different auditory stimuli, and we studied the drivers' responses to the stimuli. Repeated-measures analysis of variance revealed a significant differences between subjects exposed to different auditory stimuli (ρ < 0.05). Through post hoc analyses, we examined these differences. We found significant differences between factor 1 (stability) and factor 2 (simulation driving), between factor 1 (stability) and factor 3 (driving + police siren), and between factor 1 (stability) and factor 4 (driving + police siren + music). In addition, the factor that produced the highest level of sympathetic nervous system activity was factor 4 (driving + police siren + music), followed by factor 3 (driving + police siren), factor 2 (driving), and factor 1 (stability). In conclusion, even when a police siren was heard during driving, there were no significant differences on electrocardiograms (ECGs). In addition, even when the siren was heard over the music, there was no difference on the ECGs (ρ < 0.01). In future studies, investigators should determine which types of music help stabilize the heart rate during driving.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.3
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• pp.12-21
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• 2013

This paper deals with a comparative analysis of changes in cognition of city image of Daegu City, focusing on image of representative and environmental conditions. Two-questionnaire surveys were conducted to compare the change of image cognition between the last decades. Major results are: Firstly, the most frequent representative images of Daegu City were hot weather, Palgong Mountain, textile industry, etc. and representative places were Palgong Mountain, Dongsung-ro Street, E world(Woobang Land), etc. Compared to the results of year 2000, the frequency of apple, and textile industry were remarkably decreased. Secondly, mean scores of image rating for environmental conditions were comparatively high in human environment such as women, and kindness. By individual variables, accessibility to Daegu City, women, living environment such as shopping, showed higher mean scores. Generally, mean scores of 2011 survey were higher than that of 2000. Thirdly, major factors affecting city image were human environment, living environment, natural environment, and transportation environment, respectively. These results can be used as a basic data for strategies to improve higher brand image of Daegu City.

• Journal of Nutrition and Health
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• v.48 no.3
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• pp.289-297
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• 2015

Purpose: This study was conducted in order to determine the difference of Importance and Performance Related service management and feeding practices of teachers at mealtime in childcare centers. Methods: In December, 2013, questionnaires were completed by teachers working at childcare centers in Geumcheon-gu, Seoul. A total of 179 teachers responded to questions regarding perceived importance and degree of performing related service management and feeding practices at mealtime in childcare centers. Factor analysis and Importance-Performance Analysis (IPA) were used. Results: Four factors including 11 items were represented by factor analysis: 'Personal hygiene management', 'Feeding practice', 'Food material management', and 'Service at serving foods'. For 'Personal hygiene management', scores for perception on importance and performance were 4.42 and 3.84 points of 5 that were the lowest among factors. As a result of IPA, teachers were aware of the importance and performed well, 'Encouraging and praising children's eating habits at mealtime', 'Giving thanks before and after a meal', and 'Sitting and eating with children at mealtime' belonged to 'Feeding practice'; whereas they were not aware of the importance and performed insufficiently, 'Wearing the hygiene hat for serving foods', 'Wearing disposable gloves for serving foods', and 'Wearing the apron for serving foods' belonged to 'Personal hygiene management'. Conclusion: For children's health and safety in foodservice at childcare centers, personal hygiene management is very important when cooking as well as serving food. The results suggest that education targeting personal hygiene management is necessary for management of hygiene by teachers while serving food in childcare centers. In addition, guidelines on service management and feeding practice are needed for teachers working at childcare centers.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.23 no.2
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• pp.145-149
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• 1978

This experiments were conducted to find out the physiological characteristics of lowland weed for physiological control. Temperature, moisture, light, oxygen. carbon dioxide and soil texture effect on germination and sprouting of weed seed. But this research was conducted to know the relationship between oxygen concentration and germination on 7 species weed.

• Spatial Information Research
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• v.18 no.3
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• pp.85-94
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• 2010

This study presented a method to allocate RFID reader sites for the weekly no driving day program. In resent years, three metropolitan cities begin to operate the system to resolve the traffic jam, air pollution, and oil cost, which is expected to be operated across the country in a few years. In this regard, the accurate verification of the observance of the cars which are participated in the system is needed so that the more benefits are rewarded to observing participants but not violating ones. Thus, this study distinguished road sections where the system of the Daegu metropolitan city cannot determine the observance of the participated cars when the cars detour the RFID readers by employing a set of data from the traffic census, digital maps, and terrestrial photographs of the superstructures on the roads. Then, the appropriate sites for additional RFID readers were determined based on those sections in the road network and the types of the road superstructures.