• 한국재료학회지
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• 제21권8호
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• pp.456-460
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• 2011

Microelectromechanical systems (MEMS)-fabricated suspended devices were used to measure the in-plane electrical conductivity, Seebeck coefficient, and thermal conductivity of 304 nm and 516 nm thick InGaAlAs films with 0.3% ErAs nanoparticle inclusions by volume. The suspended device allows comprehensive thermoelectric property measurements from a single thin film or nanowire sample. Both thin film samples have identical material compositions and the sole difference is in the sample thickness. The measured Seebeck coefficient, electrical conductivity, and thermal conductivity were all larger in magnitude for the thicker sample. While the relative change in values was dependent on the temperature, the thermal conductivity demonstrated the largest decrease for the thinner sample in the measurement temperature range of 325 K to 425 K. This could be a result of the increased phonon scattering due to the surface defects and included ErAs nanoparticles. Similar to the results from other material systems, the combination of the measured data resulted in higher values of the thermoelectric figure of merit (ZT) for the thinner sample; this result supports the theory that the reduced dimensionality, such as in twodimensional thin films or one-dimensional nanowires, can enhance the thermoelectric figure of merit compared with bulk threedimensional materials. The results strengthen and provide a possible direction in locating and optimizing thermoelectric materials for energy applications.

• 한국정보과학회논문지:시스템및이론
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• 제29권9호
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• pp.493-502
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• 2002

다중 컴퓨터 네트워크의 고장 감내에 대한 대표적인 결정적 척도로 연결도와 에지 연결도가 있다. 연결도나 에지 연결도는 어떤 정점 분리 집합이나 에지 분리 집합을 제거했을 때 남은 그래프의 형태를 고려하지 않는다는 문제가 있다. 이러한 단점을 보완하기 위해서 superconnectivity, toughness, scattering number, vertex-integrity, binding number, restricted connectivity와 같은 일반화된 연결성 척도들이 함께 사용된다. 이 논문에서는 재귀원형군과 하이퍼큐브의 고장 감내에 대한 이러한 결정적 척도를 분석하고, 고장 감내 측면에서 비교한다.

• 한국지능시스템학회논문지
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• 제10권4호
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• pp.299-303
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• 2000

정보 검색 시스템의 목표는 사용자가 원하는 정보를 빠른 시간 내에 효율적으로 검색하는 것이다. 이를 위해 불리언 모델, 벡터 모델을 비롯한 기존의 많은 검색 모델들과 퍼지 이론에 기반한 퍼지 검색 모델들이 제안되어져 왔다. 그러나 기존의 모델들은 관련 문서를 검색하는데 잇어서 사용자의 선호도를 반영하지 못하는 한계점을 지닌다. 본 논문에서는 기존의 퍼지 검색 모델의 단점을 보완하기 위해서 확장 퍼지 검색 모델을 제안하고 설계하였다. 제안하는 모델은 색인어와 문서 가중치의 유사도를 결정하는데 있어서 사용자의 선호도를 반영할 수 있도록 설계하였다.

• 한국의류학회지
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• 제19권2호
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• pp.287-296
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• 1995

measuring surface area errors can be brought about with different measuring people. This study aims at eliminating such errors in measurement. With measures by 3 people whose experience varies from person to person, the existing area measuring method using a planimeter and two other methods which use a computer (one using a digitizer and the other using a scanner) have been analyzed and compared. Three methods have not shown a meaningful difference in respect to the value" of area and two methods other than the one using a scanner have shown a meaningful difference among 3 measuring people. Therefore, we propose the method using a scanner by image processing should be a more improved one for area measuring. The arguments for that are as fllows. 1. The operation for measurement is simple and it has a high degree of accuracy with few errors. 2. Because different measuring people cause few errors the operation started by one person can be handed over to anyone else and the operation dosen't require previous skill. 3. Once image file is saved, the operation can be performed on several computers at the same time with seperate part on each computer. 4. Three methods have needed nearly the same length of time, but time for the method using a scanner can be reduced on computers with a higher capacity.th a higher capacity.

• 한국의류학회지
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• 제32권7호
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• pp.1160-1168
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• 2008

The purpose of the study was to examine the effect of motif categories and motif colors on evaluating impressions of dress wearers. The research was conducted on a quasi experimental basis, with subjects numbering 187 male and 207 female college students. Data were collected in the period from march 19th to march 31st, 2007. A set of stimuli of dress wearers and semantic differential scales were developed. The stimuli were thirteen photographs editing by Youngwoo CAD system. Variables included; (a) motif colour(red, blue, achromatic and white) (b) motif categories(flower, paisley, stripes, zebra effect and plain). The semantic differential scale to measure impressions of dress wearer stimuli included 22 sets of hi-polar adjectives. The data were analysed by factor analysis and ANOVA and the major finding were as follows. Four factors emerged to account for dimension of impression. There were salience, attractiveness, comfort and femininity. The motif category effected on the four impression dimensions while the motif color effected on salience, comfort and softness sensory dimensions, and the results supported the gestalt theory of the impression perception.

• 한국소음진동공학회논문집
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• 제18권2호
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• pp.263-271
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• 2008

Compressor radiated noise is one of the dominant noise for the outdoor unit of the air conditioner. Therefore, air conditioner makers are trying to reduce it continuously. Even though noise absorption and isolation technology are one of the important parts for reducing the noise from the compressor, it is usually treated to the substitute technology when the noise from the compressor is very difficult to reduce by the compressor noise control only. In this paper, we focus on the property of the sound insulation for the cabinet and measure it applying the theory of the sound transmission loss and insertion loss of the simple enclosure. The insertion loss is evaluated by the experiments according to the thickness and the aperture of the partition in the cabinet.

• Journal of Preventive Medicine and Public Health
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• 제41권6호
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• pp.387-396
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• 2008

Objectives : During the past two decades, food deprivation and hunger have been recognized to be not just the concerns of only underdeveloped or developing countries, but as problems for many affluent Western nations as well Many countries have made numerous efforts to define and measure the extent of these problems. Based on these efforts, the theory and practice of food security studies has significantly evolved during the last decades. Thus, this study aims to provide a comprehensive review of the concept and measurement of food security Methods and results : In this review, we introduce the definition and background of food security, we describe the impact of food insecurity on nutrition and health, we provide its measurements and operational instruments and we discuss its applications and implications. Some practical information for the use of the food security index in South Korea is also presented. Conclusions : Food security is an essential element in achieving a good nutritional and health status and it has an influence to reduce poverty The information about the current understanding of food security can help scientists, policy makers and program practitioners conduct research and maintain outreach programs that address the issues of poverty and the promotion of food security.

• 비파괴검사학회지
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• 제20권5호
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• pp.402-411
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• 2000

이 연구에서는 점탄성 재료중의 하나인 아스팔트 세멘트의 점탄성 특성을 초음파를 이용하여 측정하는 방법에 대하여 고찰하였다. 2.25MHz의 주파수에서 $-20^{\circ}C$부터 $60^{\circ}C$까지의 온도변화에 따른 파속도와 감쇠를 측정한 후, 선형 점탄성 이론에 근거하여 저장 및 손실 종탄성율, 손실 탄젠트, 저장 및 손실 종컴플라이언스와 같은 물성변화를 구하였다. Maxwell과 Voigt-Kelvin 점탄성 모델을 이용하여 응력완화 및 크리프 거동과 점도의 변화도 예측하였다. 또한 중첩원리와 이동인자의 타당성을 문헌에 보고된 결과와 비교함으로써 입증할 수 있었다.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 1999년도 춘계학술발표논문집 논문집
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• pp.11-15
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• 1999

The discrete state theory on emotion postulated that there existed discrete emotions, such as happiness, anger, fear, disgust, and so forth. Many investigators who emphasized discreteness of emotions have suggested that discrete emotions entailed their specific activities in the autonomic nervous system. The purposes of this study were to develop a model of emotion-specific physiological response patterns. The study postulated six emotions (i.e., happiness, sadness, anger, disgust, fear, and surprise) as the basic discrete emotions. Thirty eight college students participated in the present study. Twelve slides (2 for each emotion category) were presented to the subjects in random order. During resting period of 30 s prior to the presentation of each slide, four presentation of each slide, four physiological measures (EEG, ECG, EDA, and respiration) were recorded to establish a baseline. The same physiological measures were recorded while each slide was being presented for 60 s (producing an emotional sate). Then, the subjects were asked to rate the degree of emotion induced by the slide on semantic differential scales. This procedure was repeated for every slide. Based upon the results, a model of emotion-specific physiological response patterns was developed: four emotion (fear, disgust, sadness, and anger) were classified according to the characteristics of EEG and autonomic responses. However, emotions of happiness and surprise were not distinguished by any combination of the physiological measures employed in this study, suggesting another appropriate measure should be adopted for differentiation.

• 한국식품과학회지
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• 제21권6호
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• pp.735-741
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• 1989

For the accurate prediction of freezing time, probably the most difficult factor to measure and major error source is the surface heat transfer coefficient. In this work, surface heat transfer coefficient were determined for still air freezing and immersion freezing methods by theory of the transient temperature method and confirmed by using a modification of plank's equation to predict the freezing time of ground lean beef. The results showed the cooling rate of immersion freezing was about 11 times faster than that of still air freezing method. A comparison of surface heat transfer coefficient of copper plate and ground lean beef resulted an difference of 25-30% because the food sample surface is not smooth as copper plate. Also, when h-values measured by ground lean beef were applicated to modified model, the accuracy of its results is very high as difference of about 8%.