• 한국소음진동공학회논문집
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• 제22권11호
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• pp.1057-1063
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• 2012

A cycloid speed reducer is a type of the speed reducers. The cycloid speed reducer has a eccentric rotating motion and offset to avoid some problem of assembly, so it has a disadvantage for vibration. In this paper, a multi-body dynamic model is developed for a cycloid speed reducer and the dynamic behaviors of the reducer are investigated. The cycloid speed reducer consists of cycloidal plate gears, housing gear, input shaft, output pin and shaft, and eccentric bearings. Using a CAD program, each component of cycloid reducer is modeled based on the offset and multi-body simulations are performed using Recurdyn. As a result, the pin reaction force and the amplitude of bearing displacement are increased by the offset.

• Journal of Preventive Medicine and Public Health
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• 제54권4호
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• pp.265-274
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• 2021

Objectives: Given the importance of social determinants of health in promoting the health of slum residents, this study was conducted with the aim of identifying the main dimensions and components of these determinants. Methods: This scoping review study was conducted according to the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews). A comprehensive search was performed of PubMed, ProQuest, Scopus, and Web of Science for articles conducted from 2010 to the end of 2019. Studies were selected based on inclusion criteria, with a special focus on studies dealing with the social determinants of physical and mental health or illness. Results: Thirty-three articles were selected to extract information on the social determinants of health. After reviewing the articles, 7 main dimensions (housing, socioeconomic status of the family, nutrition, neighborhood characteristics, social support and social capital, occupational factors, and health behaviors) and 87 components were extracted as social determinants of health among slum dwellers. Conclusions: This framework could be used by planners, managers, and policy-makers when making decisions affecting the health of these settlements' residents due to the common characteristics of slums around the world, especially in developing countries.

• 항공우주시스템공학회지
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• 제14권6호
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• pp.18-25
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• 2020

This study investigated the structural behaviors and safety of an electro-mechanical linear actuator and a load simulator with a plate spring. The material and dimensions of the plate spring were determined by theoretically calculating the stress and torsional angle for the rating load of the actuator. Thereafter, a flexible multibody dynamics (FMBD) analysis was conducted on the linear actuator and load simulator to confirm the performance of the load simulator and acquire the reaction forces acting on the actuator and simulator. The structural safety of the linear actuator and load simulator was evaluated via finite element analysis using the aforementioned reaction forces. Consequently, the proposed linear actuator and load simulator were determined to be structurally safe; however, the safety factors for the actuation rod and the housing on the actuator were excessively high. Therefore, the weight and cost must be reduced to improve their design parameters in the future.

• 한국화재소방학회논문지
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• 제32권5호
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• pp.112-121
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• 2018

본 연구는 소방기술사(Fire Professional Engineer)의 안전의식, 안전행동과 인명안전의 관계를 검증하기 위하여 기술통계 분석, 요인 분석, 신뢰도 분석, 상관관계 분석을 실시하였으며, 연구가설을 설정하여 단순회귀 분석, 3단계 매개회귀분석을 실시하였다. 분석 결과, 소방기술사의 안전의식이 높아지면 안전행동은 72.1% 상승하고, 안전의식과 안전행동이 높아지면 인명안전은 각각 61.5%와 64.5%가 상승하는 것으로 나타났다. 또한 안전행동은 안전의식과 인명안전의 관계에서 부분매개효과가 나타났다. 모든 연구가설(H1, H2, H3, H4)의 채택으로 소방 관련법은 인명안전 중심으로 개정되어야 한다는 필요성이 통계적으로 검증되어, 향후 인명안전을 반영한 분석 자료로 널리 활용 될 것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제28권10호
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• pp.1512-1518
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• 2015

This experiment was conducted to assess the welfare and productivity of gestating gilts in groups with the electronic sow feeding (ESF) system compared to conventional stalls. A total of 83 gilts ($Yorkshire{\times}Landrace$) were housed into individual stalls to be artificially inseminated. Gilts confirmed pregnant were introduced to their treatment, conventional stalls (ST) or groups with the ESF system. All gilts were taken to the farrowing crates one week prior to their expected farrowing date. In the gestation period, there were no significant differences between gilts allocated to ST and ESF on growth performance. However, backfat thickness gain (p = 0.08) and body condition score (BCS) at 110 days of gestation (p = 0.10) tended to be higher in ESF gilts than ST. Likewise, gilts housed in group showed significantly higher estimated body muscle contents at 110 days of gestation (p = 0.02) and body muscle change during gestation (p = 0.01). There was a trend for a shorter parturition time in ESF gilts (p = 0.07). In the lactation period, group housed gilts showed a tendency to increased BCS changes (p = 0.06). Reproductive performance did not differ with the exception of piglet mortality (ST = 0.2 no. of piglets vs ESF = 0.4 no. of piglets; p = 0.01). In blood profiles, ST gilts showed a higher cortisol level at 110 days of gestation (p = 0.01). Weaning to estrus interval was shorter in gilts housed in ESF than ST (p = 0.01). In locomotory behaviors, ESF gilts recorded a tendency to elevate locomotion score at 36, 70, and 110 days of gestation (p = 0.07, p = 0.06, and p = 0.06, respectively). Similarly, ESF gilts showed significantly higher incidence of scratches at 36, 70, and 110 days of gestation (p = 0.01). Moreover, farrowing rates were higher in stall treatment (97.6%) compare to group housing treatment (95.2%). In conclusion, while group housed gilts with ESF system positively affected welfare status in combination with less physiologically stressful environments and activity, it negatively effects piglet mortality, farrowing rates and injuries of gilts.

• 한국지반공학회논문집
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• 제31권11호
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• pp.5-13
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• 2015

저소음, 저진동 공법으로 널리 사용되고 있는 매입말뚝도 과거와 달리 정재하시험 보다는 동재하시험을 이용한 지지력 확인시험을 많이 수행하고 있다. 본 연구의 목적은 선단부 근처의 지반조건이 상이한 곳에 시공된 두본의 매입말뚝의 최종 경타동안에 획득된 힘과 속도 파형을 대하여 동적해석을 수행하여 매입말뚝의 지지 및 관입 거동을 분석하는 것이다. 파동방정식을 근거로 하는 동재하시험 분석 프로그램으로는 CAPWAP과 WEAP 등이 있으며 본 논문에서는 실제 현장에서 동재하시험을 수행한 매입말뚝을 CAPWAP과 WEAP을 이용하여 분석하였다. 동재하시험에서 측정된 데이터를 분석한 CAPWAP의 입력값과 결과값, 힘-속도 그래프 파형을 분석하였고, WEAP의 입력조건을 변화시키며 CAPWAP 결과와 유사한 WEAP 결과를 도출하였다. 이 때, 선단부 근처의 지반조사 결과를 고려하여 관입 깊이에 따른 N치의 분포가 지수 함수 형태이면 입력조건 중 Toe quake의 값이 작으며 이로 인해 큰 지지력이 얻어지고, 관입 깊이에 따른 N치의 분포가 선형 함수 형태이면 이와 반대되는 결과가 얻어진다. 또한 정확한 값을 구하기 어려운 해머 및 말뚝 쿠션의 강성 입력값으로서 500kN/mm 이하인 값을 추천할 수 있었다. 본 연구는 WEAP으로 실제 측정된 데이터를 분석하는 CAPWAP과 유사한 결과를 얻을 수 있으며, WEAP을 이용하여 매입말뚝의 지지력 평가가 가능함을 보여준다.

• Journal of Animal Science and Technology
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• 제57권1호
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• pp.1.1-1.11
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• 2015

Background: Due to increased interest in animal welfare, there is now a need for a comprehensive assessment protocol to be used in intensive pig farming systems. There are two current welfare assessment protocols for pigs: Welfare Quality$^{(R)}$ Assessment Protocols (applicable in the Europe Union), that mostly focuses on animal-based measures, and the Swine Welfare Assurance Program (applicable in the United States), that mostly focuses on management- and environment-based measures. In certain cases, however, animal-based measures might not be adequate for properly assessing pig welfare status. Similarly, welfare assessment that relies only on environment- and management-based measures might not represent the actual welfare status of pigs. Therefore, the objective of this paper was to develop a new welfare protocol by integrating animal-, environment-, and management-based measures. The background for selection of certain welfare criteria and modification of the scoring systems from existing welfare assessment protocols are described. Methods: The developed pig welfare assessment protocol consists of 17 criteria that are related to four main principles of welfare (good feeding, good housing, good health, and appropriate behavior). Good feeding, good housing, and good health were assessed using a 3-point scale: 0 (good welfare), 1 (moderate welfare), and 2 (poor welfare). In certain cases, only a 2-point scale was used: 0 (certain condition is present) or 2 (certain condition is absent). Appropriate behavior was assessed by scan sampling of positive and negative social behaviors based on qualitative behavior assessment and human-animal relationship tests. Results: Modification of the body condition score into a 3-point scale revealed pigs with a moderate body condition (score 1). Moreover, additional criteria such as feed quality confirmed that farms had moderate (score 1) or poor feed quality (score 2), especially those farms located in a high relative humidity region. Conclusions: The developed protocol can be utilized to assess welfare status in an intensive pig farming system. Although further improvements are still needed, this study is a first step in developing a pig welfare assessment protocol that combines animal-, environment-, and management-based measures.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.247-252
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• 2006

오염 퇴적물내 중금속의 방출과 이에 따른 생이용성(bioavalability)은 기존의 가역 평형관계로써 설명하기에 불충분한 것으로 알려져 있다. 최근 연구결과에 의하면 이러한 탈착 저항성을 설명하기 위한 비가역적 모델에 의해 퇴적물내 중금속의 탈착저항성 부분이 존재함이 밝혀졌다. 탈착저항성에 대해서는 아직 충분한 규명이 이루어지지 않았으나, 오염물질의 노화(aging)에 의해 일단 탈착저항성을 띠게 되면 생이용성(bioavailability)이 감소되는 것으로 알려져 있다. 본 연구에서는 노화(aging)가 연안 퇴적물 내 납과 카드뮴의 흡/탈착 특성에 미치는 영향을 알아보기 위해 연속 탈착실험과 biphasic 탈착모델을 적용함으로써 납과 카드뮴의 탈착저항성을 규명하고자 하였다. 그리고 연속 추출 실험을 통해서 노화(aging)에 따른 퇴적물 내 납과 카드뮴의 흡착 기작을 규명하고자 하였다. 연속탈착 실험 결과 시간이 경과함에 따라 탈착저항성부분의 크기가 증가하였으며, 연속추출 실험 결과 납의 경우 carbonate fraction에서 추출된 납이 가장 많았으며, 노화(aging) 따라 exchangeable fraction에서 추출된 납이 감소하는 반면 reducible, organic material, residual fraction에서 추출된 납의 양이 증가하였다. 카드뮴의 경우 가장 많은 양이 추출된 단계는 exchangeable fraction이였으며, organic material fraction에서는 카드뮴이 추출되지 않았다. 노화(aging) 따라 reducible fraction과 residual fraction에서의 추출량이 증가하는 경향을 보였으나 그 양은 매우 적은 것으로 나타났으며, 노화(aging)에 따른 exchangeable fraction과 carbonate fraction에서의 추출량은 큰 변화가 없었다. 대해서는 북한지역의 분포상황을 밝혔다.것을 알 수 있었으며, 크롬과 비소의 경우는 초기에 많이 용출되고, 구리의 경우는 꾸준히 용출되는 것을 알 수 있었다. 3년 된 통나무집이 8년 된 통나무집보다. 용출양이 더 컸으며, 이는 CCA성분이 초기에 많이 용출된다는 것을 의미한다. 억제 효과를 나타내었고 Hep3B에서는 부탄을 분획물 (1 mg/mL)에서 82%의 비교적 높은 성장억제효과를 나타내었다.as a "front" and "back". Thus, Germany′s private space may face a genuine public space and street, which is rare in the Korean housing. Although the layout of indoor space in the korean housing tends to be open, such an openness may be outstanding in living and dining spaces, kitchen and various accesses to rooms. In the case of Germany, such indoor spaces are usually closed to each other. Thus corridors act to separate these spaces. Such differences are analysed to be due to the different perceptions of interpersonal and socio-cultural attributes as intra-family and inter-neighbor relationships or communications. 알 수 있었다.도 질소와 인산처럼 토양지지대가 있는 경우가 낮은 함량을 유지하였다.pe from the daily life, to fantasize and daydre

• 대한지역사회영양학회지
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• 제9권6호
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• pp.706-715
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• 2004

The objective of this study was to compare early child care center teachers' attitudes for meal and snack guidance between Sweden and Korea. Participants were 251 early child care center teachers (Sweden: 134, Korea: 117) working in Goetebory, Sweden, and Seoul, Korea. The survey was conducted from December in 2003 to February in 2004. SPSS programme was used for statistical analysis. Sixty five point eight percent of the Korean early child care center teachers provided a certain amount of foods for children. But $20.9\%$ of Swedish provided a certain amount of foods for children, $79.1\%$ of them provided the amount a child wanted. Sixty one point seven percent of Korean teachers allowed a child leave foods on the plate, but $95.5\%$ of Swedish teachers asked a child eat all food on the plate. When a child didn't want to eat, $61.1\%$ of the Korean teachers fed him/her, but $11.0\%$ of the Swedish teachers did. Only $42.4\%$ of the Swedish teachers allowed a children eat sweets, but $92.9\%$ of Korean did. The Swedish teachers' perception for food guidance were eating by child himself/herself > washing hands before eating > having appropriate table manner > eating as talking with friends > not playing during the meal time, while the Korean teachers' was taking various food > having appropriate table manner > eating by child himself/herself, not playing during the meal time > washing hands before eating. The Swedish teachers thought 'eating as talking with friends' and 'eating by child himself/herself' is important, where as the Korean's did 'eating without making noise', 'not playing during the mealtime' in the eating behavior. For 'brushing teeth after meal' the Swedish teachers' score (1.5) was lower than the Korean (4.2). The results is necessary to improve meal and snack guidance for Korean early child care center teachers' education.

• 한국가정과교육학회지
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• 제19권2호
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• pp.103-114
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• 2007

본 연구의 목적은 여자 고등학생의 교복변형에 대한 학생의 태도를 분석함으로써 청소년들의 교복변형행동에 영향을 미치는 요인을 파악하고, 청소년들에게 만족스러우면서도 유행흐름에 부합하는 교복을 제안할 수 있도록 기여하는데 있다. 본 연구의 결과를 요약하면 다음과 같다. 첫째, 학생의 교복착용에 대한 태도를 살펴본 결과, 교복착용에 대해서는 찬성하는 것으로 나타났으며, 찬성의 이유로는 또래집단과의 동질성을 들었다. 둘째, 교복만족에 대한 학생의 태도를 분석한 결과 대체로 만족이 불만족보다 높은 것으로 나타났으며, 특히 디자인에 대한 만족도가 높았다. 셋째, 교복변형경험을 묻는 질문에서 대부분의 학생이 교복변형 경험이 있는 것으로 분석되었으며, 교복 상의의 경우 주로 품과 길이를 줄여 입으며, 하의의 경우 스커트 길이를 늘이고 주름을 뜯어 늘여 입는 것으로 분석되었다. 넷째, 심층면접을 통해 교복변형의 원인을 조사한 결과, 크게 미적욕구 충족을 위한 변형, 유행을 따라가기 위한 변형, 맞음새를 위한 변형, 실용성을 위한 변형으로 분류되었으며, 미적욕구충족을 위해 변형한다는 의견이 가장 많았고, 맞음새를 위한 변형, 유행을 따르기 위한 변형 순으로 나타났다. 교복 디자인시 고려사항으로는 '맞음새'를 가장 많이 선택하였으며, '디자인', '활동성' 순이었다. 이상과 같이 각급 학교에서는 학생의 의견을 교복선정에 적극 활용하여 학생들의 교복변형을 줄이고, 학생뿐 아니라 교사 학부모들도 모두가 만족하는 교복을 만들기 위한 다각적인 노력이 필요하리라 여겨진다.