Composite materials consisting of pure aluminum matrix reinforced with different amounts of graphite particles are successfully fabricated by mechanical ball milling and spark plasma sintering (SPS) processes. The shrinkage rates of the composite powders vary with the amount of graphite particles and the lowest shrinkage value is observed for the composite with the highest amount of graphite particles. The current slopes of time increase with increase in the amount of graphite particles whereas the current slopes of temperature show the opposite trend. The highest thermal conductivity is achieved for the composite with the least amount of graphite particles. Therefore, the thermal properties of the composite materials can be controlled by controlling the amount of the graphite particles during the SPS process.

In experiment dealt with 240 Hanwoo (172 steers and 68 heifers) among the 456 cattle during growing and fattening period were used from 2004 to 2015. Growth period was divided into 6, 12, 18, and 24 months for steers and 6, 12, 18, and 43 months for heifers. The results showed that lying down, feeding, and drinking behavior increased according to the growth. In contrary, the time of locomotion behavior including standing and walking behavior were reduced. Aggressive behavior was observed to be mostly generated in the first 6-months. Thus the results showed that different growth period of Hanwoo steers can be used as management systems for breeding and disease management. It conclude that providing a comfortable living space is a useful management systems suppress stress to the minimum extent without giving unnecessary stress to the animals.

The industrialization and urbanization forced to increase the density of pipelines such as water supply, sewers, and gas pipelines. The materials used for the existing pipe lines are mostly composed of concretes and steels, but it is true that the development for more durable and efficient materials has been continued performed to produce long lasting pipe lines. Recently, underground pipes serve in diverse applications such as sewer lines, drain lines, water mains, gas lines, telephone and electrical conduits, culverts, oil lines, etc. In this paper, we present the result of investigation pertaining to the structural behavior of unplasticized polyvinyl chloride (PVC-U) flexible pipes buried underground. In the investigation of structural behavior such as a ring deflection, pipe stiffness, 4-point bending test, experimental and analytical studies are conducted. In addition, pipe stiffness is determined by the parallel plate loading tests and the finite element analysis. The difference between test and analysis is about 8% although there are significant variations in the mechanical properties of the pipe material. In addition, it was found by the 4-point bending test there is no problem in the connection between the pipes by coupler.

이 논문에서는 곡선 프리스트레스트 콘크리트 사장교의 풍하중에 의한 정적 횡방향 휨거동 해석에 비선형 해석 모델 특성들이 미치는 영향을 검토하여 곡선 프리스트레스트 콘크리트 사장교의 풍하중에 의한 정적 휨거동을 정당하게 예측할 수 있는 해석방법을 제시하였다. 곡선 프리스트레스트 콘크리트(PSC) 사장교의 시공단계별 풍하중에 의한 횡방향 휨거동 해석 시 재료의 비선형성은 물론 기하학적 비선형성을 모두 고려하였고 재료의 시간의존적 특성의 영향으로 콘크리트의 크리프, 건조수축, 강도증가와 프리스트레싱(PS) 강재와 케이블의 이완을 고려하였다. 곡선 PSC 사장교의 풍하중에 의한 휨거동을 다양한 비선형 해석 모델 특성들을 조합해서 고려하여 해석을 수행한 결과, 교량 상판의 인장균열 및 이에 따른 처짐의 증가를 정확히 예측하기 위해서는 재료의 비선형 응력-변형률 관계는 물론 콘크리트의 인장균열을 모두 포함한 재료 비선형성과 기하강성도 매트릭스는 물론 대변위에 의한 변형률의 비선형항 및 부재의 위상변화를 모두 포함하는 기하학적 비선형성을 고려한 해석이 반드시 필요함을 확인하였다. 부가적으로, 콘크리트의 인장증강효과 및 뼈대요소의 축력에 의한 기하강성도 매트릭스의 고려여부는 교량의 풍하중에 의한 정적 휨거동을 예측하는 데 영향을 크게 미치지 않는 것으로 나타났다. 또한 풍하중에 의한 곡선 PSC 사장교의 횡방향 휨거동은 상판의 횡방향 변위의 상당한 증가 및 거더 단면의 인장균열로 인해 상판이 폐합되기 직전단계가 폐합된 이후 단계보다 크게 불리함을 확인하였다.

These days, thanks to lots of smart devices and advanced communication technologies, consumer’s recognition and relations have been changed. They, beyond relying on information and services which are produced by experts, produce information and knowledge by themselves via SNS or web that they want to know. As consumer’s recognition is changing like this, SNS is evolving into social platform. Therefore, this paper is intended to clarify overall relationship between network characteristics in social platform, knowledge sharing, social capital, social innovation and customer’s value. This paper has clarified influences between variables related to consumer’s behaviors in social platform and the results are summarized as following: First, network characteristics in social platform are found to positively affect knowledge sharing efforts of social platform. Second, knowledge sharing has been found to positively affect social capital and innovation in social platform. However, enjoyment in helping others i.e a sub variable is found to positively affect social capital and innovation through anticipated reciprocal relationships. Third, social capital and innovation in social platform have affected customer value in social platform positively. Consequently, this paper is intended to solve various problems found from overall societies and industries through social innovation and also to advance them. For these purposes, social platform is believed to prompt sharing idea and knowledge based on interactions between users and social relationship. These actions become social capitals resulting in social innovation. Moreover, these would create new businesses and marketing opportunities across various areas in the processes that innovative activities form customer values.

Numerical analysis has been carried out to investigate particles behavior characteristics during the grinding process in the air. Grinding particles behavior is largely affected by many parameters such as operating conditions and process room geometry. Transient particle motion in the air is predicted, and the effects of particle diameter and device rotational speed on the behavior characteristics were compared. When particle size is not large enough, they shortly moves in a tangential direction of the device rotation, and then are mostly influenced by the air flow in the room. These results could be applicable to the optimal design of the grinding process room.

극저온 액체 상태의 LNG는 주거용과 산업용으로 공급되기 전에 가스 상태로 변환된다. 이러한 재가스화 과정 중에 LNG는 83.7×104 kJ/kg 정도의 많은 냉열에너지를 제공한다. 이 냉열에너지를 일부 선진국들에서는 질소, 수소, 헬륨과 같은 극저온 유체들의 액화, 제빙 및 냉방시스템에 이용하고 있다. 따라서 우리나라에서도 인천, 평택 및 통영 LNG 인수기지 주변에 LNG의 냉열에너지를 이용한 냉열에너지 회수시스템을 설립할 필요가 있다. 여기서는 저열유속상태에서 상변화를 동반하는 LNG의 유동거동 특성을 파악하기 위해 LNG의 85 %를 차지하는 메탄을 작동유체로 사용하였다. 또한 본 논문은 극저온 열교환기 내부를 흐르는 메탄과 질소, 프로판, R11 및 R134a의 유동경계에 영향을 주는 관 직경, 관의 경사각도 및 포화압력의 효과를 보여준다. 또한 여기서 얻어진 이론적 연구결과와 기존의 실험 데이터와도 비교 되었다. 그리고 메탄의 유동경계에 주는 파이프의 경사각도의 영향은 매우 큼을 알 수 있었다.

Increasing numbers of Korean adults, especially women, are adopting vegetarian diets for various reasons. In this study, the characteristics of vegetarianism among females residing in Seoul were examined. In addition, the dietary habits and eating behaviors between vegetarians and non-vegetarians were investigated. A total of 148 females (73 vegetarians, 75 non-vegetarians) were recruited and questionnaires regarding their demographic characteristics and eating habits were completed. The eating behavior and daily intake of food groups was assessed using the three factor eating questionnaire-R18 (TFEQ-R18) and food frequency questionnaire, respectively. The ages, BMI, education, and religious affiliation were not significantly different between the two groups. More than 30% of vegetarians had followed a vegetarian diet for longer than 24 months. The most common motivations for vegetarianism in study participants were ‘health or weight control’ (46.6%) followed by ‘environmental concerns or animal welfare’ (24.7%). Vegetarians had a lower intake of cereals, Kimchi, and soda, but a higher intake of potatoes and sweet potatoes, vegetables, mushrooms, seaweed, and fruits compared to non-vegetarians. Significant differences in eating behavior scores were also found between the two groups; in particular, vegetarians reported higher levels of restrained eating and emotional eating than non-vegetarians. Scores of uncontrolled eating, however, were not significantly different between the two groups. In conclusion, these results suggest that while vegetarianism is associated with healthy dietary habits, it is associated with restrained eating behaviors which may increase the risk of eating disorders in women.

This study examined the food purchasing behavior of rural housewives in Bibong-myeon, Hwaseong. The survey targeted grocery shopping for the home, in particular by housewives. The type of grocery store frequented, age, socioeconomic factors, and ease of purchase were compared with interests in health foods. One super supermarket (SSM), three supermarkets (SM), and four convenience stores were examined in the research area, whereas a large-scale discount store and grocery stores were also examined outside the research area. The grocery store visiting rate was 61.5% in the research area and 38.5% in the other area. The SSM (62.7%) and SM (29.9%) in the research area and LDS (57.1%) and SSM (16.7%) in the other area were most frequently visited. Major purchasing products greatly differed according to the grocery store type. Major foods purchased in the SSM were grain, meat, and fish. Major foods purchased in the LDS and SM were processed products and vegetables, respectively. The LDS visiting frequency was 41.7% for 2-3 times per month and 41.7% for <1 time per month. The means of transport were mostly by private car (87.5%), whereas the SSM was visited 1-2 times per week 53.1% of the time by foot. In addition, various grocery stores are absent in rural areas and it is therefore important to find other methods to assess the food environment of rural areas. In future research, it will be necessary to design various ways to perform food environment research.

본 연구에서는 우리나라 해기사들의 행동특성을 파악하고, 이를 통제하기 위한 방안을 제시함으로써 해양안전 문화설계를 용이하게 하고자 하였다. 한국선원 377명을 대상으로 실증분석 결과, 우리나라 선원은 일반적인 한국인의 성격특성 중 “정이 많다”는 것이 가장 뚜렷한 인식을 보였으며, 유교적 관습이 아직도 해상직업 종사자들에게도 영향을 많이 끼치는 것으로 나타났다. 그러나 직책별, 성별, 선종별 집단간에는 행동특성의 차이를 보이지 않았으나 학력별로는 차이가 있는 것으로 나타났다. 한편 한국선박의 안전운항을 위해 동원될 수 있는 수단은 한국선원의 집단 구성에 관계없이 부적 강화물을 제공하는 것보다는 정적 강화물을 제공하는 것이 도움이 될 것으로 판단된다. 선박의 안전관리 수단은 학력수준 외는 집단별 차이가 없는 것으로 나타나, 선원의 학력수준에 맞는 안전관리방안을 도입하는 것이 안전관리의 효율성을 높일 것으로 판단된다.

본 연구는 인천경제자유구역 청라지구에 도래하는 큰기러기의 월동지 비오톱구조와 행동특성 간의 관계를 분석하여 큰기러기 월동지 보전관리를 위한 기초자료를 제공하고자 수행하였다. 청라지구 비오톱의 주요 유형은 갈대습지 6,093,762m2(47.8%), 볏짚이 없는 논 2,927,916m2(23.0%), 볏짚이 있는 논 1,915,655m2(15.0%)이었으며, 얼음이 있는 논, 건조초지 등이 일부 분포하였다. 2005년 2월 13일 현장조사 결과 청라지구에서 관찰된 전체 야생조류는 총 33종 6,534개체이었으며, 이 중 큰기러기는 총 5,128개체이었고 출현한 전체 종 중 78.5%를 차지하는 우점종이었다. 큰기러기 이동경로 분석 결과, 일출 전 후를 기점으로 잠자리에서 채식지로 이동하였고, 일몰 전 후를 기점으로 채이장소에서 잠자리로 이동하였다. 큰기러기의 행동특성과 비오톱 유형의 관계를 종합해보면, 갈대습지에서 큰기러기 개체군의 출현밀도가 가장 높았으며, 얼음이 녹은 무논에서 큰기러기의 출현 개체수가 가장 많았다. 갈대습지에서 큰기러기는 식물의 뿌리 및 열매를 채식하였으며, 얼음이 녹은 무논에서는 낙곡 채식, 휴식, 수면하는 등 다양한 행태를 보였고 볏짚이 있는 논과 볏짚이 없는 논에서는 낙곡 채식 및 휴식을 하였다. 큰기러기의 출현 개체수는 논에서는 논경작지의 유형보다 낙곡 유무에 따라 영향을 받는 것으로 판단되었다.

This study investigates the elastic behavior characteristics of GRP pipes reinforced with trapezoidal ribs instead of rectangular ribs. Han(2006) proposed GRP pipe reinforced with rectangular ribs in 2006, to promote buckling strength of the pipe. But it is more difficult to reinforce pipe with rectangular ribs than external corrugated ribs, because of pipe manufacturing process referred to as filament winding. Therefore, This study investigated the elastic behavior characteristics of the GRP pipe reinforced with trapezoidal ribs for simplifying analysis approach of external corrugated ribs.

GRP (Glass fiber reinforced polymer plastic) pipes are classified into flexible pipe category because of the structural characteristics of GRP pipes buried underground. Moreover, the ring deflection of GRP pipe is affected by the certain factors such as pipe stiffness, the modulus of soil reaction of backfill materials, and bedding conditions. In this study, we investigated the structural characteristics of the GRP pipes buried underground considering the soil-pipe interaction including bedding angle, pipe stiffness, and soil density used as a backfill material. From this parametric study, it was found that the soil density used for the backfill is the most important factor relating to the ring deflection of the buried GRP pipe.

사용후 핵연료내 우라늄 및 초우란원소를 회수하는 파이로프로세싱 공정에서 배출되는 금속염화물계 방사성 폐기물은 높은 휘발특성과 붕규산계 유리와의 낮은 상용성으로 인해 고화처리가 쉽지 않은 폐기 물이다. 이를 위해, 본 연구에서는 고화처리의 한 방법으로 탈염화 반응을 통한 고화체제조 개념을 채택 하였다. 솔젤법을 이용하여 탈염화물질, SiO2-Al2O3-P2O5 (SAP)을 합성하였으며 이를 이용하여 탈염화 반 응거동 반응생성물의 고형화 특성을 조사하였다. LiCl계 폐기물과 달리, LiCl-KCl폐기물의 반응은 두 개 의 온도범위에서 반응이 진행되며, 400℃의 경우에는 LiCl이, 약 700℃에서는 KCl이 주로 반응하는 것으 로 확인되었다. 여러 가지 반응실험을 통하여 LiCl-KCl의 탈염화 반응에 가장 적합한 물질은 SAP 1071 (Si/Al/P=1/0.75/1 in molar)인 것으로 확인되었다. 4가지 종류의 고형화 실험을 통하여 고화체의 bulk shape과 densification은 SAP/Salt의 비에 영향 받는 것을 확인하였다. 제조된 고형화 시료는 Product Consistency Test-A법을 이용하여 기본적인 내구성을 평가하였다. 본 연구는 SiO2, Al2O3, P2O5 로 이루 어진 탈염화 물질을 이용하여 반응특성과 고형화 특성에 대한 기본적인 정보를 제공하였으며, 이와 같은 실험을 통하여, 본 연구에서 제안된 탈염화 고화처리방법이 휘발특성이 높고 기존 유리매질과 상용성이 낮은 금속염화물계 폐기물에 적용이 가능함을 확인하였다.

The purpose of this study was to analyze the difference in bakery choice attributes according to consumers' general characteristics and purchasing behavior. Among 350 questionnaires distributed to bakery consumers, 277 complete questionnaires (79.1%) were analyzed. Bakery choice attributes were classified into five factors: "environment and image", "bakery product features", "location", "employee service", and "price and sales promotion"; the mean scores of these factors' importance levels were 3.59, 3.58, 3.49, 3.36, and 3.00, respectively. Males considered 'employee service' factor significantly more than did females. Further, the importance level of 'employee service' factor was significantly greater as consumer's age increased. The importance levels of 'bakery product features' and 'employee service' factors were considered significantly more by consumers who spent KRW10,000-15,000 than those who spent KRW5,000 or less. 'Price and sales promotion' was considered to be more important by consumers who obtained information from the Internet than from the TV and radio. 'Location' factor was considered to be more significant as purchasing frequency increased. Such differences in importance level of bakery choice attributes according to consumers' gender, age, job, and purchasing behavior should be considered and applied to the development of marketing strategies targeted at consumers.

 ,  , To investigate host preferencse of Myzus persicae on 15 sweet pepper cultivars grown in Jeonnam Province, EPG (electrical penetration graph) and life table experiments were carried out in the laboratory. Phloem phase times were significantly longer on Ferrari, Jinju, Debla, and Rapido than Orobell and Thialf. Non-penetration times were conversely observed. Life span, reproduction period, total fecundity, and intrinsic rate of increase (r<, SUB>, m<, /SUB>, ) of M. persicae, were higher on Ferrari, Debla, Orange glory, and Jinju than on Purple, GreenAce, Orobell, and Thialf. On the bases of these results, we conclude that M. persicae preferred Ferrari, Jinju, Orange glory, and Debla among the 15 tested sweet pepper varieties. However, we could not show the preference of the aphid for Purple, Orobell, and Thialf.

The purpose of this study was to examine drivers’ driving behaviors and eye-movements according to driving speed and navigation-position while operation of the navigation in driving. For this purpose, two driving conditions (low-speed and high-speed) and

주각부는 상부의 강구조와 철근콘크리트조 기초의 접합부로써 매우 중요한 부분이다. 현재 국내외 강구조 골조 공사에서 사용되는 주각부의 형식은 크게 구분하여 노출형 주각부 근권형 주각부, 매입형 주각부라고 할 수 있다. 이 중에서 부재의 재사용 및 재활용을 최우선으로 고려한다면 노출형 주각부가 가장 유리하다. 본 연구에서는 이러한 노출형 주각부의 시공 성능 및 역학적 성능을 획기적으로 개선할 수 있는 형태의 강구조 선형상 노출형 주각부를 개발하고, 구조 성능 평가를 위한 탄소성 재하실험을 수행하였다. 그 결과 개발된 신형상 노출형 주각부는 수평 방향과 수직 방향의 시공 오차를 현장에서 간단히 흡수하여 기존 노출형 주각부의 시공 불량을 사전에 방지함으로써 구조 성능을 발휘한다. 또한 에너지 흡수형 고력볼트를 사용함으로써 변형 성능이 증가함을 알 수 있었다.