• 한국정밀공학회지
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• 제17권12호
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• pp.209-216
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• 2000

The lateral behavior of the moving web is critical to the quality of the web products. The alignment of the rollers carrying the web is found to be one of important factors to the lateral behavior of the moving web. But, the study on the effect of the tilting roller in the direction of the normal to the moving web on the lateral behavior has not been reported in the literature yet. For example, the contact roller often contacts the winding roll in a tilted fashion and causes the lateral motion of the winding web, which induces the offset on the wound roll. The lateral dynamics of the moving web induced by a tilted roller in normal direction of a web is investigated in this paper. The two-dimensional dynamic model developed by Shelton is extended to investigate the effect of a titled roller in a normal direction of the moving web on the lateral motion of the moving web. New boundary conditions are developed to solve the extended model. Computer simulation study proved that the model developed can be used to predict the lateral motion of the moving web ？ to a tilted roller in normal direction of the moving web. The lateral deflection is increased exponentially a the tilting angle is increased. As the length of web span is increased, the amount of lateral deflection was increased almost linearly for the same tilting angle. The lateral dynamics turned out to be almost independent to the operating tension. The model developed can be used to solve the offset problem of the staggered winding and also to design a new web guiding mechanism.

• 한국실내디자인학회논문집
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• 제13권3호
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• pp.84-92
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• 2004

This study concentrates on a new idea that is formulated as a creative spatialization in contemporary architecture and painting. It is stimulated from the classical baroque, which is expressed with the conceptual instruments, 'excessive', 'decorative', 'accidential' Suggested from that, this study tries to open the actual sense area of 'the baroque' by analysing the architectural ideas of wrenching and folding by Frank O. Gehry and in the same context by elucidating the dynamic deformalising of the figures by Francis Bacon. The redefined 'new baroque' operates in the chain of the transformable and flexible images that must be recognized as 'the real' in the sense of 'the most empirical' and are vulnerable to dispersal. The typical instrument of Gehry's 'new baroque architecture' is the enclosing of the space and its folding, and Bacon, whose painting can be called as the modern baroque, takes as the expressing methods a wrenching of the figures, a relieving of the colored background against the figure and a disappearing of figures into the background. These different ideas meet in the theoretical gravitation field of the philosophy of Deleuze, in which the reconstituted baroque conception means the tension between the folds, on expansion and contraction of which the variable space is dependent, Through the general principle of 'the new baroque', a free dispersal of power, to architect and painter is offered the possibility, not only to make the real world intimate to the real life, but also to produce from there a vivid new space. Finally it brings to enjoyer and viewer the possibility, to perceive the operating power in and around oneself.

• 대한의용생체공학회:의공학회지
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• 제24권1호
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• pp.15-21
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• 2003

본 연구에서는 경량휠체어 탑승자의 차량 전방충돌시 안전성 평가를 위하여 동적 슬래드 충격실험을 하였다. 실험은 총 6회 시행하였으며 충격속도는 20g/48 $\pm$2km/h 였고, Hybrid III 50%ile 성인남자 인체모형을 사용하여 두부손상기준(Head Injury Criteria), 목의 굴전모멘트, 축 인장력, 전단력, 흉부 가속도. 두부, 휠체어, 무릎의 전방 쏠림량을 측정하였으며 미국자동차학회 규격인 SAE J2249에서 제안한 동작기준 (Motion Criteria)과 미국 제너럴모터스사의 자체기준(GM-IARV)인 복합상해기준(Combined Injury Criteria)을 이용하여 안전성평가를 하였다. 실험결과는 경량 휠체어 탑승자의 전방 충돌 시 최대 상해치를 100%로 봤을 때 휠체어와 탑승자 거동의 위험도지수 MC는 52%, 탑승자의 상체 위험도지수 CIC는 60.1% 였다.

• Wind and Structures
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• 제4권1호
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• pp.1-18
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• 2001

The classical two-degree-of-freedom (2-d-o-f) "sectional model" is currently used to study the dynamics of suspension bridges. Taking into account the first pair of vertical and torsional modes of the bridge, it describes well global oscillations caused by wind actions on the deck and yields very useful information on the overall behaviour and the aerodynamic and aeroelastic response, but does not consider relative oscillation between main cables and deck. The possibility of taking into account these relative oscillations, that can become significant for very long span bridges, is the main purpose of the 4-d-o-f model, proposed by the Authors in previous papers and fully developed here. Longitudinal deformability of the hangers (assumed linear elastic in tension and unable to react in compression) and external loading on the cables are taken into account: thus not only global oscillations, but also relative oscillations between cables and deck can be described. When the hangers go slack, large nonlinear oscillations are possible; if the hangers remain taut, the oscillations are small and essentially linear. This paper describes the model proposed for small and large oscillations, and investigates in detail the limit condition for linear response under harmonic actions on the cables (e.g., like those that could be generated by vortex shedding). These results are sufficient to state that, with geometric and mechanical parameters in a range corresponding to realistic cases of large span suspension bridges, large relative oscillations between main cables and deck cannot be excluded, and therefore should not be neglected in the design. Forthcoming papers will investigate more general cases of loading and dynamic response of the model.

• 한국콘텐츠학회논문지
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• 제15권4호
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• pp.65-74
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• 2015

본 연구는 히치콕 영화 <The Man Who Knew Too Much(1956)>의 사운드를 퍼스의 기호학적 관점에서 다루고 있다. 본고는 기호학적 논의에 앞서 퍼스의 이론을 살펴보고, 대사, 배경소리, 음악으로 구성된 사운드의 3요소를 그가 제시한 기호의 부류에 따라 분석해 보았다. 음악은 음정을 통해 지표기호로서 감정을 나타내기도 하며, 일차성 범주의 악기소리는 내러티브적 요소로 작용하여 이차성의 발화기호로 전이되면서 역동적 대상이 되기도 한다. 또한, 낱말기호로서의 대사 한 단어는 영화에서 도상기호를 통해 암시적으로 대상을 재현하기도 하며, 지표기호로서의 배경소리와 음악은 영화의 긴장감을 높이는데 기여하고 있다. 한편, 병치관계의 두 다른 장르의 음악은 발화기호로서 서술적 기능을 담당하고 있다. 이렇듯, 히치콕에 있어 사운드는 컨텍스트에 따라 의미작용을 달리하는 기호학적 특질을 갖는다.

• 한국방재학회 논문집
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• 제8권4호
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• pp.39-45
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• 2008

본 연구는 면적 $0.293\;m^2{\sim}0.360\;m^2$의 소형표지판용 지주의 풍하중에 대한 구조적 안정성을 유지하면서도 작은 충돌에도 분리가 일어나도록 고안된 내경 6 mm의 D12 mm 중공형 인덴티드 볼트를 이용한 소형지주용 브레이크어웨이 단부장치의 구조적 안전성을 정적 전단 및 인장실험으로 입증하고 동적특성을 이해하는데 기본이 되는 인덴티드 볼트의 분리 파괴에너지를 펜듈럼 실험과 비선형 동적해석 프로그램인 LS-DYNA 프로그램을 이용하여 구하고 두 가지 방법을 비교한 것이다. 인덴티드 볼트 3개로 이루어진 단부장치는 풍하중 43.1 kg$\sim$51.2 kg를 충분히 지지할 수 있는 것으로 나타났으며 인덴티드 볼트 1개 당 파괴에너지는 펜듈럼 실험값이 163.3J, 시뮬레이션 값이 153J로 유사하게 계산되어 모델의 유효성이 확인되었다.

• 접착 및 계면
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• 제6권2호
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• pp.13-20
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• 2005

환경 친화적인 자연섬유 강화 고분자 복합재료의 계면 전단강도는 총체적인 기계적 물성을 조절하는데 매우 중요한 역할을 수행한다. Ramie와 Kenaf 섬유 강화 에폭시 복합재료의 계면 전단강도는 최종 물성을 위한 최적 조건을 찾아내기 위해 미세역학시험법과 비파괴 음향방출시험을 이용하여 평가했다. Ramie와 Kenaf 섬유의 동적 접촉각을 측정했고, 계면 접착에서 젖음성과 상호 관련시켜서 해석하였다. Ramie와 Kenaf 섬유의 기계적 물성은 단섬유 인장시험을 통해 조사했고, 통계학적으로 uni-와 bimodal Weibull 분포를 통해서 분석하였다. Ramie와 Kenaf 섬유에 대한 실제 신장율의 clamping 효과의 영향도 평가할 수 있었다. 두 가지의 다른 미세파괴 형상은 섬유다발과 단섬유 복합재료로부터 오는 축방향의 debonding과 섬유상의 fracture는 인장과 압축하중하에서 관찰할 수 있었다.

• 한국방재학회 논문집
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• 제10권5호
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• pp.27-33
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• 2010

본 연구에서는 2,000 kN 용량의 actuator를 이용, 12 m 경간의 실물 크기로 제작된 프리스트레스트 콘크리트 보의 구조성능 평가를 위한 실험을 수행하였다. 보의 양 단에는 접합을 위한 강판을 매립하였으며 시험체는 별도로 제작된 철골 보에 고력볼트접합 방식으로 세팅되었다. 프리스트레스트 콘크리트와 슬래브 콘크리트의 설계기준강도는 각각 50 MPa와 24 MPa이며, 인장 철근으로 사용된 2-HD25 철근은 매립강판의 구성요소 중 하나인 수직강판에 용접하였다. 실험은 변위제어법에 의하여 수행되었으며 10 mm의 변위를 증가시키며 loading과 unloading을 반복적으로 가력하였다. 실험결과를 살펴보면, 탄성거동구간에서는 약 88.34%, 비탄성거동구간에서는 약 86.97% 그리고 소성거동구간에서는 약 66.83%의 프리스트레싱에 의한 변위복원능력을 나타냄을 알 수 있었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.380-387
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• 2004

Recently the geosynthetics reinforced retaining wall has been widely used instead of the steel reinforced retaining wall. The geosynthetics reinforced retaining wall is a very dangerous structure if the geosynthetics lose their strength about tension or if it lose their pullout resistence, but it was known that the geosynthetics reinforced wall had a great resistence and was a very safe structure against a earthquake or a dynamic load. It can be said that most important factors in the stability of the geosynthetics reinforced wall are the horizontal length of reinforcement and the vertical distance between two reinforcements. That is to say, as the length of reinforcement is longer, the structure is more stable and as the vertical distance between two reinforcements is shorter, it is more stable. In this study, in order to get the critical condition with a safety rate of 1, various kinds of model tests about geosynthetics reinforced wall has been performed. Photos by B-shutter method has been taken during tests and from photos, which show us the failure state, the critical condition about failure has been conformed. Accordingly the equation, which says the limit of stability in geosynthetics reinforced wall., has been proposed.

• 한국해양공학회지
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• 제23권5호
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• pp.45-53
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• 2009

In this study, Finite Element Analysis (FEA) was used to decide three kinds of material property of vibration proof rubber with the unique characteristic of non-linear and large deformation. As well, three types of hardness (Hs 50, 55, 60) were compared with the result of fatigue tests, fatigue life was able to be predicted. The request for fatigue life becomes strict more and more as increasing stress under conditions like a compaction, high load and high temperature for parts because it is main characteristics of rubber mount for automotive. Regarding to the fatigue life under dynamic deformation condition, it can be predicted as checking forced deformation extends and its frequency and its strain-life curve. As for material property tests of uniaxial tension test, uniaxial compression test, pure shear test, Ogden model was used for FEA by observing relations between stress and strain's rate as curve fitting. As a result of FEA, fatigue life for rubber mount was predicted and accorded well with the experimental data of fatigue test with hourglass specimens. In addition, its property of the predictable fatigue life method suggested in this study was accorded well with the experimental data by comparing the predicted fatigue life of FEA with the result of fatigue test for rubber component of engine rubber mount.