• 한국항공우주학회지
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• 제48권8호
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• pp.565-571
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• 2020

본 논문에서는 항공기 Wing-box 모델에 대한 비선형 구조해석의 계산을 정확하고 효율적으로 수행하기 위해 병렬계산 알고리즘을 개발하였다. 이를 위해 co-rotation 이론 기반 비선형 쉘 요소를 적용하였으며 요소기반 분할 병렬계산 알고리즘을 개발하였다. 기 개발 해석은 선행연구결과 및 기존 상용프로그램의 예측결과와 비교하여 정확성을 확인하였으며 병렬계산의 효율성을 분석하였다. 마지막으로 고세장비 날개 wing-box 구조에 적용하였으며 단방향 공력-구조 결합해석을 수행하였다.

• ETRI Journal
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• 제36권4호
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• pp.581-590
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• 2014

This study investigates the impact of tweets on box office revenue. Specifically, the study focuses on the times when tweets were written by examining the impact of pre- and post-consumption tweets on box office revenue; an examination that is based on Expectation Confirmation Theory. The study also investigates the impact of intention tweets versus subjective tweets and the impact of negative tweets on box office revenue. Targeting 120 movies released in the US between February and August 2012, this study collected tweet information on a daily basis from two weeks before the opening until the closing and box office revenue information. The results indicate that the disconfirmation that occurs in relation to the total number of pre-consumption tweets for a movie has a negative impact on box office revenue. This premise suggests that the formation of higher expectations of a movie does not always result in positive results in situations where tweets on perceived movie quality after watching spread rapidly. This study also reveals that intention tweets have stronger effects on box office revenue than subjective tweets.

• 한국수산과학회지
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• 제29권2호
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• pp.143-149
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• 1996

우리나라 멸치어업에서의 1971~1992년 동안의 22년간 월별 어획량 자료를 시계열 분석하여 어획량을 분석, 예측하였다. 시계열 분석은 다른 생물학적, 해양학적, 사회 경제적인 요소가 없어도 단지 어획량 자료만으로 분석과 예측이 가능하다. 첫 20년간인 1971~1990년 사이의 월별 멸치 어획량 자료를 ARIMA 시계열 모형에 적용시켜 구한 결과는 다음과 같다. 로그 (대수) 변환시켰을 때의 ARIMA 모형: $$(1-0.381B)(1-0.027B^{12}+0.141B^{24})(1-B^1)(1-B^{12})Z_t=(1-0.968B)(1-0.727B^{12})e_t$$, Box-Cox 변환시켰을 때의 ARIMA 모형: $$(1-0.431B)(1-B^{12})Z_t=(1-0.882B^{12})e_t$$, 위의 두 모형중 Box-Cox 변환시킨 것이 로그 (대수) 변환시킨 것보다 예측오차가 적었으며, Box-Cox 변환식은 $Y'=(Y^{0.58}-1)/0.58$ 이었다. 위의 두 모형 중 후자의 모형을 이용하여 1991~1992년 사이의 월별 어획량을 예측하였다. 예측 어획량과 실제 어획량과의 월별 오차범위는 1.0~63.2% (1991년에 1.6~63.2%이고, 1992년에는 1.0~60.4%)였다. 예측 어획량이 각 연도별로 148,201M/T과 148,834M/T인데 비해, 실제 어획량은 170,293M/T, 168,234M/T이었다. 2년 동안의 총어획량에 대한 오차는 12.3%였다. 또한 스펙트럼 분석은 순환변동의 주기가 2.2개월, 6.1개월, 10.2개월, 12개월, 14.7개월에서 상대적으로 큰 성분이 있음을 나타내었다 이 순환변동 성분은 적절한 ARIMA 모형을 결정하는 데도 도움이 된다.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1997년도 춘계학술대회논문집
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• pp.95-99
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• 1997

Most studies in manual material handling (MMH) have paid more attention to single MMH activities-lifting, lowering, carrying, holding, pushing or pulling and have ignored combined activities. Also, many studies have been involved with two-handed MMH activities rather than to one-handed MMH activities. Very few studies are reported on the determination of workers' capacities for combinations of one-handed MMH activities (e.g. lifting a box, then carrying the box, and lowering the box). The objective of this study was to utilize the psychophysical approach to examine the combinations of lifting, carrying and lowering activities from a simulated industrial task involving one- handed and two-handed combined tasks and to develop mathematical models for combined tasks. Ten male students served as subjects for the study. The capacities that were determined as the maximum acceptable weight workloads for 1 hr work period for one-handed and two-handed combined tasks-lifting a box from floor to knuckle height, carrying the box for 4.3 m, and lowering the box form knuckle to floor height -were determined psychophysically under three frequencies: six handlings per minute, one handling per minute and one handling per five minutes. Combined MMH capacities models for one-handed tasks were developed. Te advantages and disadvantages of different models are discussed.

• 복합신소재구조학회 논문집
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• 제4권3호
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• pp.30-37
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• 2013

It is same such as the provision of shear buckling strength of steel composite box girder web panel and plate girder web panel in Korea Highway Bridge Design Standards(2012). But the web panel of steel composite box girder is different from the web of plate girder in that the upper slab and lower flange are connected to the web. So a different shear behavior of the girders is expected. In this study, To calculate a reasonable elastic shear buckling strength of steel composite box girder web panel, ABAQUS program was used. The results from F.E.A and previous studies are compared. It is shown that the web shear buckling strength of steel composite box girder of Korea Highway Bridge Design Standards(2012) is the most conservative.

• 비교문화연구
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• 제36권
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• pp.97-122
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• 2014

During the Edo-period [江戶時代 1603-1867], Japan accepted the modern western science and culture while trading with Holland since 1609, and also through the influx of optical instruments in the $18^{th}$ century the culture of viewing pictures began to be developed. Especially, the peep-boxes and their pictures had been imported from China and Holland since the mid 1750s when they were flourished. The peep-box was rapidly and widely spread. Soon after, the peep-boxes and pictures had begun to be produced in Japan (megane [眼鏡] and megane-e [眼鏡繪]) since 1770s when the early visual culture settled down in Kyoto and Tokyo etc. The visual culture developed with the peep-box contains two remarkable factors in the cultural history of the $18^{th}$ century Japan. First, the peep-boxes became the popular device of visual entertainment, and opened the first phase of the modern visual culture before the advent of photography and cinema in the mid and end of the $19^{th}$ century. Secondly, the peep-box played a role of an educative media as a 'window to the unknown world' in the $18^{th}$ century Japan, by showing various pictures of many European cities. Through the peep-box pictures the 'western images' were spread and knowledges of Japanese about the west increased, although they were recognized just as 'Holland's images' without differentiation in each country.

• Advances in Computational Design
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• 제6권1호
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• pp.55-75
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• 2021

The lightweight superstructure is beneficial for bridges in remote areas and emergency erection. In such weight-sensitive applications, the combination of fiber-reinforced polymer (FRP) as a material and box-beams as a structural system have enormous scope. This combination offers various advantages, but as a thin-walled structure, their designs are often governed by buckling criteria. FRP box-beams lose their stability either by flange or web buckling mode. In this paper, the web buckling behavior of simply supported FRP box-beam subjected to transverse load has been studied by modeling full box-beam to consider the effect of real state of stress (stress variation in length direction) and boundary conditions (rotational restraint at web-flange junction). A parametric study by varying the sectional geometry and fiber orientation is carried out by using ANSYS software. The accuracy of the FE models was ensured by verifying them against the available results provided in the literature. With the help of developed database the influential parameters (i.e., αs, βw, δw and γ) affecting the web bucklings are identified. Design trends have been developed which will be helpful to the designers in the preliminary stage. Finally, the importance of governing parameters and design trends are demonstrated through pedestrian bridge design.

• 한국농공학회논문집
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• 제46권4호
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• pp.39-46
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• 2004

This experiment was carried out to study on the effect of surface coating on thermal insulation of farm structures to improve thermal resistance and reflective effect of solar radiation. Nine different types of experimental specimen were compared in the temperature variations of inside and outside; A, B, C, D. E and F types are box container and G, H and I types are drum container. The size of these containers is $1,500{\times}2,000{\times}2,500$ mm and ${\varphi}$ $280{\times}330$ mm, respectively. Specimen of 3-type box(A, B, C) is galvanized steel sheet of thickness 0.45 mm. D, E and F types are sandwich panel of the thickness 50 mm inserted with urethane, glass wool and polystyrene form, respectively. G, H and I types are paint pot using in general. The surface of A. D, E, F and I types didn't any treatment, B, C and G types were treated with thermal insulation coating on the outside surface(B, G) or the inside and outside surface(C). And H type was treated with water paint coating on the only outside surface. In general, the experimental results showed the following tendencies; In case of A, B and C types. it was found that the thermal insulation effect of types coated with thermal insulation coating was improved remarkably than that of no treatment. And the thermal insulation effect between steel sheet and sandwich panel type was nearly similar There was not a significant difference of thermal insulation effect between thermal insulation coating and water paint coating. In time of drum container filled with rough rice, The difference of heat transfer tendency and temperature variation among surface treatments was nearly similar that of box types of galvanized steel sheet. And there was time lag about 6 hours between the temperature of middle part of rice and that of inside or outside surface.

• Molecules and Cells
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• 제39권3호
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• pp.250-257
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• 2016

Abiotic stresses such as drought and low temperature critically restrict plant growth, reproduction, and productivity. Higher plants have developed various defense strategies against these unfavorable conditions. CaPUB1 (Capsicum annuum Putative U-box protein 1) is a hot pepper U-box E3 Ub ligase. Transgenic Arabidopsis plants that constitutively expressed CaPUB1 exhibited drought-sensitive phenotypes, suggesting that it functions as a negative regulator of the drought stress response. In this study, CaPUB1 was over-expressed in rice (Oryza sativa L.), and the phenotypic properties of transgenic rice plants were examined in terms of their drought and cold stress tolerance. Ubi:CaPUB1 T3 transgenic rice plants displayed phenotypes hypersensitive to dehydration, suggesting that its role in the negative regulation of drought stress response is conserved in dicot Arabidopsis and monocot rice plants. In contrast, Ubi:CaPUB1 progeny exhibited phenotypes markedly tolerant to prolonged low temperature ($4^{\circ}C$) treatment, compared to those of wild-type plants, as determined by survival rates, electrolyte leakage, and total chlorophyll content. Cold stress-induced marker genes, including DREB1A, DREB1B, DREB1C, and Cytochrome P450, were more up-regulated by cold treatment in Ubi:CaPUB1 plants than in wild-type plants. These results suggest that CaPUB1 serves as both a negative regulator of the drought stress response and a positive regulator of the cold stress response in transgenic rice plants. This raises the possibility that CaPUB1 participates in the cross-talk between drought and low-temperature signaling pathways.

• 콘크리트학회논문집
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• 제26권6호
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• pp.707-714
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• 2014

콘크리트 충전강관(CFT)은 강관의 내부에 콘크리트로 채워진 기둥이다. CFT는 강재와 콘크리트로 구성되며, 강재는 콘크리트를 내부에서 구속시켰고, 내부 콘크리트는 기둥의 압축하중을 감당한다. 본 실험에서 73~100MPa급 고강도 콘크리트에 관해 유동성실험, 압축강도실험, 압송압력실험을 실시하였으며, CFT용 고강도 콘크리트의 물리적 성질을 알아보기 위해 슬럼프, 슬럼프 플로우, 공기량, U-box시험, O-Lot시험, L-flow시험이 진행되었다. 이러한 연구의 결과를 바탕으로 Mock-up테스트에서 콘크리트 충전성 시험, 수화열 측정 시험, 응력계측 시험을 수행하였다. 현장적용은 상암동 및 서강대 현장의 두 곳에 각각 ${\Box}-566{\times}566{\times}10$, ${\Box}-400{\times}400{\times}25$의 대상기둥을 선정하여 현장계측을 진행하였다. CFT기둥의 장기거동 예측에 관하여 설계하중에 대해 콘크리트의 탄성변형과 건조수축, 크리프 수축을 고려한 ACI 209 재료모델을 사용한 결과는 계측결과와 거의 일치하였다.