• 대한가정학회지
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• 제23권1호
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• pp.33-47
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• 1985

The rheological properties of acorn starch gel were investigated in region of small and large deformation. The properties were compared with those of potato and wheat starch gel. On the physical characteristics and the effect of tannin contents of acorn starch were examined. RESULTS : 1. X-ray diffractogram of acorn starch showed C-type and its granules swelled gradully with heating. 2. Hardness, brittleness and both small and large deformation of the acorn starch gel were remarkably large, also the concentration dependence of the acorn starch gel could be recognized in small deformation and hardness. 3. The Young's modulus of Hookean body in small deformation and the rupture stress in large deformation differed obviously from the parameters of rheological properties in various gels. 4. It was found that the selling power, viscosity and rhelogical properties were affected obviously by the tannin.

• 한국기계가공학회지
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• 제9권1호
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• pp.14-18
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• 2010

Car muffler has the role to form the exhaust gas from high temperature- pressure to lower level and reduce the generated noise. Because of this role, its durability decrease as deformation by heat is occurred. This study is to analyze the flow of exhaust gas inside muffler and its coupled thermal deformation with 3-D modeling and ANSYS. There is the fastest flow at the exit of muffler with the maximum velocity of 54 m/s. And the maximum deformation or equivalent stress is shown at this model respectively as 0.00435 mm or 3414.4 MPa by the influence of heat and pressure at part of intersection with inlet and body of muffler.

• 소성∙가공
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• 제7권1호
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• pp.81-93
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• 1998

Identification of forming limits of sheet metals is an important task to be done before the sheet metal forming processes. The information of the forming limit is indispensable for design of deformed shapes and related forming processes. This procedure becomes more important than ever as the auto-body becomes complicated and the number of auto-body parts is reduced for lower production cost. To identify the forming limit of sheet metals stretching with a hemispherical punch has gained popularity because of the convenient experimental procedure. The stretching experiment however has localized deformation or the shear band is originated from the non-unifrom deformation in the critical circum-stance instead of the absolute criterion. More accurate information of the forming limit therefore could be obtained by a more appropriate experiment to the real process. In this papaer an experiment program is devised to practivally identify the forming limits of sheet metals for auto-body parts. The experiment program contains not only stretching but deep-drawing Both forming experiments use the same hemispherical punch while they use different specimens. Deep-drawing experiments use speci-mens cut out in circular arc on both sides of circular blank to make it torn during the deep-drawing They also use speciments cut out straight in one side of a circular blank to make it deformed unevenly which causes local deformation during the deep-drawing. The experimental result demonstrates that the forming limit diagrams in the two cases show difference in their effective magnitude. The forming limit curve from deep-drawing is located lower than that from stretching. It is noted from the result that the deep-drawing process causes acceleration of localized deformation in comparison with the stretching process. From the experimental result the maximum value of forming limit could be pre-dicted for safe design.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 I
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• pp.85-89
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• 2001

Hamiltonian modeling approach has been extensively adopted for rigid body dynamics whereas its usage for deforming flexible continuum dynamics has been limited. A set of Hamilton＇s equations for flexible body motion with finite deformation has been derived and applied for a nonlinear impact problem.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 추계 학술발표회
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• pp.252-256
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• 1996

• 한국지반환경공학회 논문집
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• 제8권6호
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• pp.77-83
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• 2007

본 논문에서는 이미 사용 중인 콘크리트표면차수벽형석괴댐(이하 CFRD)에 대하여 저수용량 확대 또는 수리 수문학적 안정성을 증대할 목적 등으로 하류측에 추가 축조하여 댐의 높이를 높이는 경우에 대하여 추가 축조과정에 기존 댐체 및 추가 축조 부분의 변형거동을 유한요소해석법으로 검토하였다. 해석결과 기존 댐체의 하류측에 덧붙여 추가 축조할 경우 기존 댐체 전반에 걸쳐 추가 변형이 발생하는 것으로 나타났다. 특히, 상류사면은 침하(댐마루측)와 융기(댐체 하부측)가 동시에 발생하며, 이 경우CFRD의 특성상 상류사면에 시공되어 있는 콘크리트 차수벽에는 휨모멘트에 의한 인장균열이 발생할 수 있는 것으로 나타났다. 따라서 기존 CFRD에 증고를 하는 경우에는 시공전에 반드시 기존 차수벽의 변형량과 휨모멘트 발생량 등을 검토하고 경우에 따라서는 적절한 보완대책의 수립이 필요한 것으로 나타났다.

• 소성∙가공
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• 제28권5호
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• pp.266-274
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• 2019

Metal sealing is used to connecting the parts between valves and fuel pipes for a FCEV which utilizes hydrogen gas of 700 bar. Instead of general carbon steel, stainless steel is the primary material used to manufacture fuel pipes due to hydrogen embrittlement. The shape of deformation between metals is an important factor on the air-tightness of the metal to metal contact. Since the stainless steel pipe is hardened using the plastic forming during the tip shaping stage, this work hardening could have an effect on the deformed shape and characteristics of contact surfaces in fastening of pipes. In this paper, the deformation history of the pipe model was considered in order to analyze the hydrogen-tightness on the metal sealing part. The contact distance and the forward displacement for fastening were compared using experimental results and the simulation results. The simulation of the effect of material change on the fitting body demonstrated that the hardness or the strength of the formed tip of the pipe was designed to a proper valued level since the characteristics of the contact surface was exhibited better when the strength of the pipe was lower than that of the fitting body.

• 한국생산제조학회지
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• 제18권5호
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• pp.477-482
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• 2009

This study analyzes the result with dynamic simulation about deformation according to time when a car impacts bollard. These results are shown as followings. The maximum deformation is shown at the lower part of front grass in case of the impact of front or passenger seat but this deformation is shown at the lower part of rear bumper in case of double impact. The maximum equivalent stress is shown at the upper part by the side grass of driver seat at the elapsed time of 0.00075 second after impact in case of the impact of front or passenger seat but this deformation is shown at the front bonnet at the elapsed time of 0.004 second after the additional impact in case of double impact. The maximum total deformation or equivalent stress is shown nearly same in case of the impact of front or passenger seat. But the value of this deformation or equivalent stress in case of the impact of front or passenger seat is shown with 2 times or more than 17% respectively as this value in case of double impact.

• 복식
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• 제60권7호
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• pp.47-60
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• 2010

The goal of this dissertation is to analyze various Romantic styles appearing in modern fashion based upon the 'Difference' theory developed by Gilles Deleuze. A new framework for analyzing the changes of dress style based upon the 'Difference' theory derived from Deleuze's theory and from his interpretations of paintings was developed. The characteristics that represent 'difference' in change of dress style are deformation and hybridization. They are derived from the Deleuze's interpretations of 'difference' represented in the paintings by Bacon. The aesthetic values of the Romantic style in the 19th century dress are subordination, sensuality, and maternity. And the formative characteristics of the Romantic style dress are suppression of body, fixed form, volume, and ornamentation. The formative characteristics of the Romantic style that have appeared since 1980s is analyzed according to deformation and hybridization and the results are as follows: first, deformation caused by exaggeration or emphasis in the modern Romantic fashion creates changeability of the form, destruction of the 19th century style, volume, and ornamentation. Second, hybridization by combining heterogeneous characteristic between times and genders (for example, the 19th century and modern times or masculinity and femininity) frees body from the dress and changes the dress silhouettes and ornamentation. Thus totally new and different Romantic style is created. The Romantic style in modern fashion changed into the appropriate style to the modern society under various conditions such as designer's will, postmodernism, changes of femininity and technology. It can be said that this is an example of the Deleuze's 'becoming' theory.

• 한국산학기술학회논문지
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• 제14권1호
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• pp.57-62
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• 2013

카트 차체에는 현가장치와 차동장치가 존재하지 않으므로 카트주행 중 발생하는 프레임의 변형은 탄성변형으로 인한 주행성능과 프레임의 피로수명에 영향을 미친다. 선회주행 시 비틀림 변형에 의한 카트의 거동은 이 두 가지 변형에 결정적 원인을 제공한다. 이러한 곡선구간에서 카트의 동적 거동을 분석하기 위하여 GPS를 이용하여 차량의 궤적을 추적하고 카트 프레임 강에 작용하는 비틀림 응력을 측정하였다. 레저와 레이싱 카트 프레임의 기계적 성질을 파악하기 위해 재질 분석과 인장시험을 실시하여 각 프레임의 재료 특성을 분석하였다. 비틀림 응력집중과 프레임 비틀림은 프레임 해석을 통해 조사되었다. 또한 주행 분석 장치를 이용하여 레저와 레이싱 카트를 각 조건별로 실차실험을 수행하였고, 이를 통해 곡선구간에서 카트의 주행거동을 분석하였다. 선회주행 시 차량에 원심력에 의한 하중이동의 현상이 발생했으며, 이로 인해 카트 프레임 강에 비틀림 응력이 발생하였다.