• 소음진동
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• 제2권2호
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• pp.125-134
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• 1992

In this study, ti identify the dynamic characteristics of automobile steering system which consists of many components and joints, each component combined structure was analyzed using commercial structural package, ANSYS. And, the finite element method for each component and modeling method of several joints universal joint, bolt joint, bearing, etc. were studied. On the other hand, the experimental modal analysis was performed to compare with the results of the finite element analysis and joint modeling. The result shows very close agreement between two analysis. Also, it was found that the steeing column used in this experiment does not effect the low frequency mode of entire system. In addition, we found that constraint equations need to be considered in modeling universal joint. Since the stiffness effect of Urethane around wheel could be ignored, it can be modeled only with mass effect. In the end, it was found that dynamic characteristics of the entire steerintg system depends mainly upon the wheel characteristics.

• Advances in Computational Design
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• 제1권2호
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• pp.207-220
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• 2016

The aim of this study is to investigate the effect of stiffened element and edge stiffener in the behaviour and flexural strength of built-up cold-formed steel beams. An experimental and analytical analysis of CFS channel sections in four different geometries is conducted, including simple channel sections, a stiffened channel section with or without edge stiffeners. Nonlinear finite element models are developed using finite element analysis software package ANSYS. The FEA results are verified with the experimental results. Further, the finite element model is used for parametric studies by varying the depth, thickness, and the effect of stiffened element, edge stiffener and their interaction with compression flanges on stiffened built-up cold-formed steel beams with upright edge stiffeners. In addition, the flexural strength predicted by the finite element analysis is compared with the design flexural strength calculated by using the North American Iron and Steel Institute Specifications for cold-formed steel structures (AISI: S100-2007) and suitable suggestion is made.

• International Journal of Naval Architecture and Ocean Engineering
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• 제7권4호
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• pp.670-690
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• 2015

In this paper, numerical investigations for tank sloshing, based on commercial CFD package FLUENT, are performed to study effects of boundary layer grid, liquid viscosity and compressible air on sloshing pressure, wave height and rising time of impact pressure. Also, sloshing experiments for liquids of different viscosity are carried out to validate the numerical results. Through comparison of numerical and experimental results, a computational model including boundary layer grid can predict the sloshing pressure more accurately. Energy dissipation due to viscous friction leads to reduction of sloshing pressure and wave elevation. Sloshing pressure is also reduced because of cushion effect of compressible air. Due to high viscosity damping effect and compressible air effect, the rising time of impact pressure becomes longer. It is also found that liquid viscosity and compressible air influence distribution of dynamic pressure along the vertical tank wall.

• 한국컴퓨터정보학회논문지
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• 제24권6호
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• pp.199-204
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• 2019

This study found out the influence of CCTV recognition and Self-efficacy on job satisfaction for 275 child care teachers working at daycare centers in Chungcheongbuk-do Province, and verified the regulation effect of Self-efficacy in the process. SPSS(Statistical Package for Social Science) 22.0 was used for data analysis. The results of the study are as follows: First, it was found that factors such as the guarantee of child's right, the guarantee of teachers' rights, and the self - efficacy were influential factors on the job satisfaction of the child care teachers. Second, it has been confirmed that the guarantee of teachers' rights and self-efficacy on the job satisfaction of child care teachers have a regulation effect. This study can be meaningful in that it provided basic data to enhance the quality of child care services by analyzing the factors of influence on the job satisfaction of child care teachers and presenting specific measures accordingly.

• International Journal of Advanced Culture Technology
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• 제8권4호
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• pp.249-254
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• 2020

This study are to show the relation between ethical consumption consciousness, life meaning and happiness of life. Specifically, this study aims to examine the mediation effects of the meaning of life in the relationship of the ethical consumption consciousness and happiness, a survey was conducted by collecting 265 valid questionnaires. SPSS and AMOS statistical package were used to examine the relationships between variables. The results showed that ethical consumption consciousness had a significantly positive effect on life meaning. It was also found that life meaning had a positive effect on happiness of life. This study is significant in the sense that it identifies ethical consumerism consciousness has a positive influence on life meaning and consumer happiness. In particular, the mediating effect of the meaning of life, which is drawing attention in various research fields, was confirmed in the relationship between ethical consumption consciousness and happiness. This study can be used as effective information for further ethical consumption education and suggested implications for enhancing ethical consumption consciousness and happiness in various ways.

• 한국의상디자인학회지
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• 제25권3호
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• pp.143-155
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• 2023

This study examined the effect of beauty service location characteristics and service quality on customer satisfaction and revisit intention, and analyzed the gender control effect of location characteristics and service quality in the relationship with customer satisfaction. The Statistical Package for the Social Sciences (SPSS) was employed and analysis was conducted to investigate how location characteristics and service quality in beauty service encounters effects customer satisfaction. The results of this study are as follows. First, visibility, which is a location characteristic, was found to have a significant effect on customer satisfaction. Second, professionalism and convenience, which are service qualities, were found to have a significant impact on customer satisfaction. Third, customer satisfaction was found to have a significant effect on the intention to revisit. Fourth, as a result of analyzing the gender control effect in the relationship between location characteristics and service quality with customer satisfaction, the gender control effect was found in all factors.

• 생물환경조절학회지
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• 제25권4호
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• pp.225-231
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• 2016

본 연구에서는 유리온실 경영비 절감을 위한 고효율 난방기술을 개발하기 위하여 지하수열원 히트펌프, 알루미늄 다겹보온커튼, 근권부 국소난방장치를 조합한 난방 패키지 모델을 구성하고 파프리카 재배 벤로형 유리온실에 적용 시험을 수행하였다. 적용효과 분석을 위하여 관행 경유온수보일러와 일반 보온커튼을 설치한 대조구 온실과 비교시험을 통해 온실환경, 난방비용, 작물생육 등을 검토하였다. 알루미늄 다겹보온커튼과 일반 부직포 보온커튼을 설치한 온실에 대한 무가온 조건에서의 야간온도 비교시험에서 알루미늄 다겹보온커튼 설치 온실의 온도가 일반 부직포 보온커튼 설치 온실에 비해 평균 $2.2^{\circ}C$ 더 높게 유지됨을 확인하였다. 또한 근권부 국소 난방장치를 설치한 온실에서 미설치 온실에 비해 야간 난방 중의 베드내부 근권온도가 $4.7^{\circ}C$ 더 높게 유지됨을 확인하였다. 난방패키지를 구성하는 지하수열원 히트펌프의 난방성능을 분석한 결과 지하수를 직접 열원으로 이용하는 시스템 특성상 난방성능계수는 평균 3.7로 비교적 높게 나타났다. 난방패키지를 적용한 처리구 온실과 관행 난방의 대조구 온실에 대하여 연료소비량을 계측한 결과 10a($1,000m^2$)당 대조구 온실은 경유 14,071L, 전력 364kWh를 소비하였고, 처리구는 전력 35,082kWh를 소비하여 난방비용 기준으로 대조구 온실의 비용 절감율은 87%로 나타났다. 처리구 및 대조구 온실의 작물생육을 비교한 결과 초장과 엽록소 함량에서 차이가 발생하였으나 두 온실의 난방온도가 거의 동일하므로 전체적인 생육은 큰 차이가 없는 것으로 분석되었다. 원예시설의 난방에너지 절감효과를 극대화하기 위해서는 본 연구의 난방패키지를 구성하는 개별 기술뿐 아니라 이미 개발된 고효율 공조기 이용기술, 보온성 향상기술, 온도관리 기술 등을 지역, 시설, 작목, 작형 등에 최적화하여 조합할 수 있는 추가적 패키지 모델의 개발 연구가 필요한 것으로 판단되었다.

• 생물환경조절학회지
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• 제19권3호
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• pp.159-164
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• 2010

염생식물 중 생체로 이용되고 있는 수송나물(Salsola komarovi Iljin)과 해홍나물(Suaeda maritima L. Dum.)의 상품화를 위해 포장 판매 및 저장이 동시에 가능한 MAP(modified atmosphere package)의 저장성을 몇가지 온도에서 비교하였다. 온실에서 재배한 수송나물과 해홍나물을 $50{\mu}m$(ceramic) 필름으로 포장하여 $2^{\circ}C$, $10^{\circ}C$, $25^{\circ}C$에 저장하였다. 저장중 생체중 감소는 모두 1% 미만이었는데, 역시 상온에서 가장 빠르게 감소하였으며, 수송에서 감소폭이 컸다. 포장재내 산소 농도는 저장온도별로는 $2^{\circ}C$에서 가장 높게 유지되었으며, $25^{\circ}C$에서는 수송이 해홍보다 낮은 농도를 보였다. 포장재내 이산화탄소 농도는 산소농도와 반대로 저장온도별로는 $25^{\circ}C$에서 가장 높았으며, 식물별로는 수송에서 높았는데 두 식물 모두 $2^{\circ}C$와 $5^{\circ}C$에서는 1% 이하로 유지되었다. 포장재내 에틸렌 농도는 $10^{\circ}C$에서 $2^{\circ}C$보다 높았으나, 통계적인 유의성은 없었다. $10^{\circ}C$에서 에틸렌 농도는 두 식물 모두 $20{\mu}L{\cdot}L^{-1}$으로 같은 수준으나, $2^{\circ}C$에서는 해홍이 다소 높았다. 온도에 따른 포장재내 이산화탄소와 에틸렌 농도는 저장온도가 높을수록 높았는데, 수송나물에서는 $2^{\circ}C$와 $10^{\circ}C$간 통계적 유의성이 있는 차이를 보인 반면, 해홍나물의 경우 그 차이에 통계적 유의성이 인정되지 않았다. 관능검사로 실시한 외관상 품질은 3점까지 상품성을 인정하였는데, 수송나물의 경우 상품성인 인정된 저장일수가 $24^{\circ}C$에서는 3일, $10^{\circ}C$에서는 7.5일 $2^{\circ}C$에서는 14일이었고, 해홍나물은 $24^{\circ}C$에서는 3.5일, $10^{\circ}C$에서는 9.5일 $2^{\circ}C$에서는 11일이었다. 외관상 품질 변화와 포장재내 이산화탄소와 에틸렌 농도로 볼 때 해홍나물의 경우 $2^{\circ}C$의 저온에서 저장성이 $10^{\circ}C$와 차이가 없어 저온장해가 의심되었다.

• 농촌지도와개발
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• 제28권1호
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• pp.25-39
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• 2021

This study aims to identify the causation effect between technostress and utilization of Internet information and meditation effect of information service acceptability between technostress and Internet information utilization. The data were collected from 503 woman farmers aged 20 to 65 across the country. The analysis performed a three-stage mediated regression of Bron, & Kenny (1986), using the SPSS 21.0 statistical package. The importance of accepting information services has been identified in the Sobel test. According to the analysis of the medium effect on information service acceptability, information service acceptability has a partial medium effect on the technological stress of woman farmers and the level of Internet information utilization. In order to lower the technology of woman farmers in the future, it is necessary to find ways to improve new perceptions of information technology and increase acceptability of information services.

• 한국수산과학회지
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• 제33권3호
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• pp.238-242
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• 2000

소건 대멸치의 저장${\cdot}$유통 중 저장안정성을 부여하고자 건조 전항산화제를 처리하여 $37^{\circ}C$에 저장하였을 때 대멸치의 지질산화는 BHT를 첨가한 것이 현저하게 억제되었으며, 그 다음으로 ${\alpha}-trlcopherol$, rosemary 추출물, sage 추출물의 순이었다. 대멸치에 있어서 ${\alpha}-tocopherol$과 rosemary 추출물을 혼합처리한 항산화제의 항산화력은 BHT의 산화억제효과와 거의 비슷하였으며, 그 적정농도는 rosemary추출물 $0.1{\%}$와 $tocopherol\;0.1{\%}$를 혼합한 수준이었다. 건조한 대멸치를 $25{\circ}C$에 저장하였을 때 진공포장한 것이 항산화제의 산화방지 효과를 증대시키는 효과가 있었다.