• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.817-821
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• 1997

Ever since the nonlinearity of machine tool dynamics was established, researchers attempted to make use of this fact to devise better monitoring, diagnostics and system, which were hitherto based on linear models. Theory of chaos, which explains many nonlinear phenomena comes handy for furthering the analysis using nonlinear model. In this study, measuring system will be constructed using multi-sensor (Tool Dynamometer, Acoustic Emission) in end millingprocess. Then, it will be verified that cutting force is low-dimensional deterministic chaos calculating Lyapunov exponents, Fractal dimension, Embedding dimension. Aen it will be investigated that the relations between characteristic parameter caculated form sensor signal and tool wear.

• Tribology and Lubricants
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• v.4 no.1
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• pp.36-42
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• 1988

On the basis of the thermally-activated Wear theory, it is well estabilished that the secondary activated energy, which is mainly resulted from the exothermic reaction of hydrogen from thermal decomposition of the hydrocarbons at the high temperature and the high speed, caused catastropic failure. The new additive, viz., DEP was synthesized to reduce or eliminate the hydrogen effect at the contact junction. Through the thermal degrading and the thermodynamic consideration, the synthesized additive, viz., DEP showed the possibiliy as the hydrogen scavenger.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.5
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• pp.755-764
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• 2015

This study investigates if the relationships between hemline and macro-economic factors (rGDP, recession, and unemployment) are still applicable as well as analyzes time lags that reflect economic factors on the hemline index using U.S. data. The hemline theory and fashion cyclical theory were applied to propose the relationships studied. The data for the hemline measurements of women's day-wear were obtained from US Vogue spring and fall editions from 1950 to 2014. Data were standardized by dividing the length from shoulder to hemline by the length from the shoulder to ankle. I aggregated 2260 samples and hemline data to create a yearly average. This study used OLS of Stata 13 program to explore the relationship between macro-economic factors and hemline. The main findings were the recession and unemployment influenced hemline length for four years in a positive direction. Furthermore, the effects of previous recession and unemployment on the current hemline were very close to the significant level respectively. This finding supports the hemline theory in that a recessionary economy is related to longer hemlines and hemlines become shorter in flourishing economic periods.

• Journal of the Korean Society of Costume
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• v.29
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• pp.143-158
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• 1996

It was the year of 1903 when avantgarde artists in Vienna gave a birth to the Wiener Werkstaette under the influence of Aesthetic Movement and Guild of Handicraft from England. This study is on the backgrounds of the birth of the Wiener Werkstaette its artis-tic motto and world-wide echo it provoked. This thesis goes back to the time when the decadent Wiener Secession shaped up refiewing the Reform Movement It also covers characteristics works of major members of the Wiener Werkstaette which were produced on the basis of the concept of Gesmtkunstwerk, The conclusion of this study is that : 1. Without losing its own specifc features various fields of formative arts were combinded together coherently and succeeded to realize the idealistic art that is the com-posite are 2. The Wiener Werkstaette was strongly opposed to the ready-made clothes which be-came popular as the society was Industrialized and commercialized. unlike those ready-to-wear clathes those members of the Wiener Werkstaette preferred to make each clothes with different mateirals and printed their own unique pattern designs. 3.As a results of close relationships between the Wiener Werkstaette and paul poiret 'Stu-dio Martine' was established in paris and new pattern deslhns were introduced by Raoul Dufy. 4. After the break-out of World War One cultural exchanges with other foreign countries were vuirtually cut off and the Wiener Werkstaette was disconnected from the influence of Parisl That was the motive for Wiener Werkstaette to start building up its unique artistic style with peculiar materials techniques and methods of productionl Those brisk and creative activities of the Wiener Werkstaette brought forth "the Golden perlod of 1920s" 5. Its historic design and ornamental pattern were assessed as a prelude to the Post-mod-ernism Since the late 1970s with the redis-covery of the culture of vienna in 1900s. the Art to wear which was created by the 'Wiener Werkstaette' but unfortunately tucked away by the Greate Depression and nationalism has been revaluated and studied. In Korea it was since 1985 when 'the art to wear' began to gain attention widely. It is urged that the theory of the 'Gesamtkunstwerk' should be also ac-cepted and shared earnestly.

• Tribology and Lubricants
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• v.19 no.1
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• pp.26-30
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• 2003

The stresses of surface and substrate under the rough surface contact are irregular. Using rainflow counting method for irregular stresses, the fatigue surface crack initiation lift was calculated. With the surface generated by computer, this paper figures out the random load generated by contacting to the rough surface, analyzes the stress of its subsurface, and calculates the fatigue crack initiation life of the rough surface fatigue theory.

• Tribology and Lubricants
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• v.18 no.2
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• pp.160-166
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• 2002

In case of rough contact fatigue, the accurate calculation of surface tractions is essential to the prediction of crack initiation life. Accurate Surface tractions influencing shear stress amplitude can be obtained by contact analysis based on the morphology of contact surfaces. In this study, to simulate rough contact under sliding condition, gaussian rough surface generated numerically in the previous study was used and to calculate clack initiation life in the substrate, dislocation pileup theory was used.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.11a
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• pp.72-79
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• 2000

In case of rough contact fatigue, the accurate calculation of surface tractions is essential to the prediction of crack initiation life. Accurate Surface tractions influencing shear stress amplitude can be obtained by contact analysis based on tile morphology of contact surfaces. In this study, to simulate rough contact under sliding condition, gaussian rough surface generated numerically in the previous study was used and to calculate crack initiation life in the substrate, dislocation pileup theory was used.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.234-238
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• 1999

This study suggests the design of the functionally gradient composite, [0/90/0/core]$_s$ cross-ply laminate, to prevent stress concentration induced from the difference of rigidity between the bone and the artificial hip joint and to reinforce the wear property of the surface and the expectation of their mechanical properties. First, the four-point bending test is done about wet bones and dry bones to know the mechanical properties of the cortical bones. In result, the wet bone shows the viscoelastic behavior and the dry bone shows the elastic behavior. Moreover, we expect the properties of the proposed gradient composites as a function of carbon fiber volume fraction in each layer to apply Halpin-Tsai equation, CLPT(classical laminate plate theory), and Bernoulli beam theory etc. and decide the thickness ratio of each lamina in order to match Young's modulus of the anisotropic cortical bone with the proposed gradient composites.

• Korean Journal of Human Ecology
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• v.18 no.3
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• pp.657-673
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• 2009

This research was focused on wives and theirs husbands who have been involved in extramarital affairs. The major purpose of this study was to find out wives' marital adaptation process and typology in the process of their husbands' affairs. The grounded theory provided the theoretical and methodological framework for this research. The qualitative data were obtained from ten wives whose husbands have had extramarital affairs through in-depth interview. The data wear analyzed through open, axial, and selective codings and formed a conditional matrix. This research classified these wives' adaptation into four types such as Separated Independent, Rigid Resigned, Connected Acceptive, and Chaotic Attached types.

• Transactions of Materials Processing
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• v.9 no.2
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• pp.128-139
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• 2000

Wrinkling is one of the major defects in sheet metal products and may be also attributable to the wear of the tool. The initiation and growth of wrinkles are influenced by many factors such as stress state, mechanical properties of the sheet material, geometry of the body, and contact condition. It is difficult to analyze the wrinkling initiation and growth considering the factors because the effects of the factors are very complex and the wrinkling behavior may show a wide variation for small deviations of the factors. In this study, the bifurcation theory is introduced for the finite element analysis of wrinkling initiation and growth. All the above mentioned factors are conveniently considered by the finite element method. The finite element formulation is based on the incremental deformation theory and elastic-plastic elements considering the planar anisotropy of the sheet metal. The proposed method is verified by employing a column buckling problem. And then, the initiation and growth of wrinkling in deep drawing of cylindrical cup are analyzed.