• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.475-478
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• 2005

Calculation of wear depth with regard to the wear topology is peformed numerically Four typical wear topology, that is round, crescent, flat, and diamond types are adopted to represent the configuration of wear volume. Diamond and flat types are the most severe topology for wear depth history, whereas round and crescent types have small increasing rate of wear depth to the wear volume. Based on this study we can guess that the most severe wear phenomena happens to be upper side of U-tubes in the KSNP SG, because flat or diamond wear will be generated by the wearing motion between tubes and diagonal, vertical, horizontal strips. The misalignment of tube at the stage of manufacturing or distortion of upper structure due to the thermal expansion or vibration of upper structure such as diagonal, vertical, and horizontal strips will be one of the main causes of flat or diamond wear.

• The Journal of Korean Academy of Prosthodontics
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• v.42 no.6
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• pp.628-640
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• 2004

Statement of problem. Wear as a result of repeated closing/opening cycles may decrease the friction coefficient of screw head, threads, and other mating components and, consequently, resistance to opening gradually decreases. It may cause screw loosening, which is one of the most common failures in implant prosthesis. Purpose. The purpose of this study is to evaluate the changes on the head and thread surface of the abutment screws after repeated closing and opening through the examination of tested screws in SEM(scanning electron microscope). Materials and methods. Five species of abutments were selected (3i-three, Avana-two) respectively by two pieces. The implant fixtures were perpendicularly mounted in liquid unsaturated polyesther(Epovia, Cray Valley Inc.) with dental surveyor. Each abutment was secured to the implant fixture by each abutment screw with recommended torque value using a digital torque controller. The abutment screws were repeatedly tightened and removed 20 times with a digital controller. FESEM (field emission scanning electron microscope, Netherland, Phillips co., model:XL 30 SFEG) was used to observe changes of each part caused by repeatedly closing/opening expeiment. First, the Photomicrographs of pre-test screws provided by each manufacturer were taken. The changes of each screw were investigated after every fifth closing and opening experiment with FESEM. Scaning electron microscope photomicrographs of each screw were taken four times. Results. As the number of closing and opening was increased, the wear or distortion of hexed or squared slot that contacted with the driver tip was more severely progressed. Wear or distortion of hexed slot was more severe than that of squared slot and it was more remarkable in the titanium screw than in the gold screw. All the tested screws showed that the width in the crest of their screw thread decreased gradually as the test was proceeded. Conclusions. Conclusively, we recommend the clinical use of gold screw, a periodic exchanges of abutment screws and avoiding repeated closing/opening unnecessarily. We also suggest a more careful manipulation of the abutment screw and screw-driver and using of abutment screw with an acute-angled slot design rather than an obtuse-angled one. Finally, it is suggested that the new slot design and the surface treatment for enduring wear or distortion should be devised.

• Journal of computational fluids engineering
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• v.10 no.1
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• pp.51-55
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• 2005

For proper installation, operation and performance of axial flow jet engines in aircrafts, the impacts and effects of inlet flow distortion in axial compressors have to be understood. Inlet distortion conditions may cause component-mismatch and instability problems known as rotating stall, and severe oscillations of mass flow rate called surge or a combination of both. Typical effects of this phenomenon include stresses and wear on the compressor blading, destruction of entire jet engines due to the failure of airfoil and mechanical failure or interruption of the combustion process. Therefore, it is important to study inlet flow distortion and its propagation effects to minimize and hence to prevent the occurrence of such calamity. The current novel integral method with parametric analysis signifies its validity to this field of research and offers much potential for further improvements. The present effort further indicates that this simple method may be flourishing in the problems of strongly distorted flow and propagating stall in axial compressor. It is therefore believe that using a more realistic and flexible velocity and pressure profiles could develop this approach further.

• The Research Journal of the Costume Culture
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• v.17 no.1
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• pp.40-54
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• 2009

Many studies make us difficult for understanding the specific concept of NOW avant garde by misusing avant garde or by using the over wide-ranging concept. The purpose of this study is to define the concept of NOW avant garde fashion by analyzing its fashion and its paradigm characteristics, after considering modern avant garde fashion history. This study was used with bibliographic research as well as internet search of qualitative method for analyzing fashion show clothes since 2005 women's wear. The characteristics of NOW avant garde fashion are classified into plural deconstructivism, econonism that integrates the last avant garde factors with logical economics, and the aesthetic of Tech-Human. To conclude, the concept of NOW avant garde fashion is defined as the fashion expressing either the digital-hybrid images or the deconstructive images meaning elimination, unification or confinement, being pilled up one on another, bizarre connection, transposition, and distortion.

• Journal of the Korean Society of Costume
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• v.55 no.7 s.98
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• pp.38-50
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• 2005

The purpose of this study is first, to see through the aesthetic essence of the clothing as art, through theoretical consideration of cultural feature and body style in Postmodern Feminism. Also, this study will examine the aesthetic value in artistic meaning regarding a Deformational body image in visual an. Second, this study will analysis the formative character of Modern Art to wear which expressed unfixed body style, followed by the change of Postmodern Feminity, as a Deformation image. This character will be categorized by Expansion, Grotesque, Pleasure, and Virtuality. The following is the result of this study. Expansion expressed in modern Art to wear created intentional structure of the form, and intentionally presented refusal of body existence through disembodied. Grotesque expressed refusal and deviation of women's ideal body style, which is defined by mannish discourse, very grotesquely. Pleasure pleasantly presented free emotion through an intentional transformation like distortion or imbalance of the body By paradoxically reproducing women's virtual body as other unfixed female identity was expressed visually through virtuality to embody post-gender.

• Journal of the Korea Fashion and Costume Design Association
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• v.20 no.4
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• pp.117-130
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• 2018

As women wear shoes for a long time due to aesthetic elements and working environment, many women experience discomfort and deformation in their feet due to their shoes and the production of comfortable shoes is becoming an important issue. The purpose of this study is to investigate the factors affecting the grip of shoes by foot type, shoe design, and wearing attitude of shoes. Through this, we suggest solutions for foot discomfort due to wearing shoes and help to prevent foot related diseases. The study results are as follows; first, a wide foot, square-type, and high or low arch (hollow foot or flat foot) among foot shapes influenced the fatigue and pain of feet, and big feet over 250mm-long, wide feet, square-type feet, and high-arch feet (hollow foot) had an influence on distortion and side effects. Second, among the characteristics of wearing shoes influencing foot discomfort, the higher the shoe heels were, the narrower the surface covering the feet was (pumps and mule), and the shoes with high front heels and narrow back heel area, the shoe wearer had a higher possibility of experiencing fatigue and pain and even had not only fatigue and pain but also side effects when she wore pointed shoes. Third, a shoe wearer experiences fatigue and pain if she wears shoes for a shorter period of time, stay stood while wearing shoes for a short time, and wears shoes that are bigger or smaller than the actual shoe size. Fourth, fatigue and pain experiencers and distortion and side effects experiencers all responded that they change into other shoes to deal with foot discomfort and that they directly massage their feet.

• The Research Journal of the Costume Culture
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• v.9 no.4
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• pp.574-591
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• 2001

This study reviews the concept and characteristics of the deconstruction philosophy in order to analyze the major aspects of the fashion world called the deconstruction fashion based on the deconstruction philosophy, and analyzes the works of Jean Paul Gaultier in terms of Derrida's deconstruction theory. The scope of this research is from 1980 to present, and this study fashion on the many kinds of literature on philosophy, aesthetics and literary criticism, and the domestic and international fashion journals and magazines. The deconstructionism is the philosophical theory which denies the traditionally recognized logocentric metaphysical theory and refuses the closed world and pursues the open world, opposing the dichotomic theory which is the deep-rooted tradition of the Western philosophy. The results of analyses centering on the internal deconstruction trend expressed in the works of Jean Paul Gaultier are as follows. 1 The past style combined with the present appears in the form of the entirely new trace, not the past emotion and meaning in Gaultier's works transcending the time and space. 2 Gaultier presents the unconventional intermeaning of meanings, producing various possibilities according to the wearing method of the wearer by layering several clothes. 3. Gaultier breaks from masculinity and femininity in the intertextuality of gender, and decomposes the fixed idea of men's or ladies'wear through the design sharing bisexual text. 4. In the intertextuality of T.P.O., Gaultier presents the problem of how to wear by mixing different items through obscuring the division of the nature of time, space, and purpose. Especially Gaultier can be called the first designer who, worthy of the father of the deconstructionism, has introduced in the fashion making inner wear like outer wear. 5. In the intertextuality of coordination, Gaultier presents a new perspective of coordination through free combination and contrast, raising a question about the man-made harmony criterion and deconstructing the clothes. On the other hand, Gaultier expresses the intertextuality of the material through the heterogeneous combination of the material. 6. The decomposition trend expressed in the many works of Gaultier reflects an open mind presenting a new perspective through the distortion of the form, exaggeration, and break from the existing construction method. 7. The decentering trend in the works of Gaultier is found to deconstruct the Western-dominated elements against the background of subcultural elements, the elements borrowed from the minority race, md the Oriental culture. 8. The discontinuity clothes of Gaultier present the disordered principle of design without the uniform rules, and express the unrestrained freedom without captivation by the preconceived idea through the disruption of the dress and its ornaments just like Gaultier.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2018.06a
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• pp.129-129
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• 2018

Hard coating application is effective way of cutting tool for hard-to-machine materials such as Inconel, Ti and composite materials focused on high-tech industries which are widely employed in aerospace, automobile and the medical device industry also Information Technology. In cutting tool for hard-to-machine materials, high hardness is one of necessary condition along with high temperature stability and wear resistance. In recent years, high-entropy alloys (HEAs) which consist of five or more principal elements having an equi-atomic percentage were reported by Yeh. The main features of novel HEAs reveal thermodynamically stable, high strength, corrosion resistance and wear resistance by four characteristic features called high entropy, sluggish diffusion, several-lattice distortion and cocktail effect. It can be possible to significantly extend the field of application such as cutting tool for difficult-to-machine materials in extreme conditions. Base on this understanding, surface coatings using HEAs more recently have been developed with considerable interest due to their useful properties such as high hardness and phase transformation stability of high temperature. In present study, the nanocomposite coating layers with high hardness on WC substrate are investigated using high entropy alloy target made a powder metallurgy. Among the many surface coating methods, reactive magnetron sputtering is considered to be a proper process because of homogeneity of microstructure, improvement of productivity and simplicity of independent control for several critical deposition parameters. The N2 is applied to reactive gas to make nitride system with transition metals which is much harder than only alloy systems. The acceleration voltage from 100W to 300W is controlled by direct current power with various deposition times. The coating layers are systemically investigated by structural identification (XRD), evaluation of microstructure (FE-SEM, TEM) and mechanical properties (Nano-indenter).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.8
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• pp.44-50
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• 2019

CMP is the most critical process in the manufacture of silicon wafers, and the use of retaining rings, which are consumable parts used in CMP equipment, is increasingly important. Since the retaining ring is made of plastic, it is not only weak in strength but also has the problem of taking a long time for the flattening operation of the ring itself performed before the CMP process, and of the imbalance of force due to bolt tightening causing uneven wear. In order to solve this problem, the retaining ring and the insert ring are integrally used, and the flatness of the retaining ring may be affected depending on the material of the insert ring. Also, the residual stress generated in the manufacturing process of the insert ring may cause distortion of the ring, which may adversely affect the precision polishing. In this study, when the insert ring is made of Zn or STS304, the thickness variation and the flatness of the retaining ring are compared and, finally, the material removal rate is analyzed by polishing the wafer by the oxide CMP process. Through these experiments, the effects of the insert ring material on the polishing accuracy of the wafers were investigated.

• Journal of Korean Physical Therapy Science
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• v.10 no.1
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• pp.30-37
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• 2003

Purpose : The purpose of this study is giving the healthy promotion and it's related data base for out-patients who had stroke via evaluating the general characters of their active daily living and physical therapy Method : This study researched 81 patients who had received physical therapy service in 6 general hospitals located Pusan city responded to the self-assessment questionnaires from July 2002 to August 2002. Conclusion : In this study, patients were composed of 61.7% of male, 65.4% of 50's-60's in the age, 56.8% of cerebral infarction, and 60.5% of right hemiplegia. 74.1% of patients received physical therapy after 6 months from an attack, only 62.9% used orthosis & gait aids, and 59.2% received medical care 2 or 3 times per week. 40.7% of patients had over 9 hours sleeping time and 22% had reduced $1{\sim}2hours$ before hospitalization. 90% did not have drinking and smoking. 91.4% had 3 times eating per day, and 67.7% did not have good nutrition. The reasons of that were their eating habit, 542% of eating-giver, 3.7% of economic problem. 46.9% of patients used healthy food. In active daily living, patients can't do drinking by cup, voiding & defication by themselves, however patients can't do wearing/take off, etiquette for dressing, bathing, stepping by themselves. 40.7% of patients don't wear orthosis, 55.6% of patients don't use W/C. Part of physical therapy that patients concerned importantly exercise for prevention of joint distortion, management of affected side, and 80% of patients was also concerned other's part, significantly. 71.8% of patients & care-givers want to receive physical therapy at home, and 74% of patients do physical therapy by themselves at home along teached hospitalization.