• Journal of the Korean Society for Heat Treatment
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• v.22 no.6
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• pp.339-344
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• 2009

Recently, Laser surface treatment technologies have been used to improve wear charactenitics and fatigue resistance of metal molding. When the laser beam is irradiated on the surface and laser speed is appropriate, the laser focal position is rapidly heated and the thermal energy of surface penetrates the material after irradiation, finally imbuing it with a new mechanical characteristic by the process of self-quenching. This research estimates the material characteristic after efficient and functional surface treatment using HPDL, which is more efficient than the existing CW Nd:YAG laser heat source. To estimate this, microstructural changes and hardness characteristics of three parts (the surface treatment part, heat affect zone, and parental material) are observed with the change of laser beam speed and surface temperature. Moreover, the depth of the hardened area is observed with the change of the laser beam speed and temperature. From the results of the experiments, it has been shown that the maximum hardness is approximately 788Hv when the heat treatment temperature and the travel speed are $1150^{\circ}$ and 2 mm/sec, respectively.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.6
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• pp.119-126
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• 2014

Micro-holes of conductive ceramic are required in micro structures. Micro-electrical discharge machining (Micro-EDM) is an effective machining method since EDM is as process for shaping hard metals and complex-shaped holes by spark erosion in all kinds of electro-conductive materials. However, as the depth of micro hole increases, the machining condition becomes more unstable due to inefficient removal of debris between the electrode and the workpiece. In this paper, micro-EDM was performed to evaluate machining characteristic such as electrode wear, machining time, taper angle, radial clearance with varying voltage and ultrasonic vibration on 10 vol.% Carbon-nanotube reinforced conductive $Al_2O_3$ composite fabricated by spark plasma sintering in previous research.

• Journal of the Korea Fashion and Costume Design Association
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• v.11 no.3
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• pp.111-124
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• 2009

Since the graphics of fashion items as a means to deliver messages suggest practical sections of the society while showing individual ideas and identity, they have values of promotion to attract attention by manifesting an effective function during the process of delivering intentions and the signification. Accordingly, this study aims to investigate the characteristics expressed with graphics shown on T-shirts of casual wear out of all the fashion items and analyze the social messages reflected on them. Using the Barthes' system of denotation and connotation, distinguished symbolic functions and meaning among graphics were analyzed through the analysis of expression methods of the graphics as the denotation of initial meaning and connotation of secondary meaning. Each casual brand has led the sale of casual markets by appealing consumers with graphic items with characters printed such as various kinds of animals and symbols or lettering printed such as hieroglyph and logos, as various expressive methods and social significance as well as a effective communicative means of graphics. As examined above, graphics expressed on fashion items have an informative characteristic and a persuasive characteristic in the aspect of contents, which has a single value as a communicative characteristic. Those characteristics have developed into the fashion graphic actively reflecting a designer's conviction, values, feelings and identity by acting on social issues and publicness. That is, in the age of information, effective messages delivered through the fashion graphic to the public have contributed to the establishment of an appropriate atmosphere of visual culture while maximizing the role and function as a social significance.

• Journal of the Korean Society of Costume
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• v.61 no.4
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• pp.38-51
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• 2011

The purpose of this study is to offer data that designers can utilize substantially, by developing creative materials in knit fashion through the analysis relevant to expression characteristics on the mixture in high low class culture, which were shown in knit fashion of contemporary women, as one of methods of pursuing a plan for being able to be appeared creative and unique knit wear. As for a method of this research, studied concept and characteristics on the mixture in high low class culture by preceding researches. And women's knit fashion was selected that is seen to be 3~18 gauge among the world's 4 collections from 2000~2008. The analysis was made with the analytical frame in mixture pattern, and the analytical frame in design element, and item. The results are as follows. The mixture of kidult element and high fashion was shown with characteristic of expressing humor and fun with graffiti, expression like character and cartoon, and fairy-tale fantasy through the exaggerated trifling article. The mixture of grungy element and high fashion was shown with the expression characteristic in the mixture of heterogenous pattern, and in tear, slit without the end treatment due to fraying the end strand in the knit fashion with basic stitch, patch work, fringing and tone-down gray, use of khaki and blue color, and match in opposite color. The mixture of underwear and high fashion was shown the expression characteristic with the emphasis on underwear line like volume up, or with the mixture of details such as pants in diverse lengths, mini skirt, underwear lace, and ribbon.

• Tribology and Lubricants
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• v.1 no.1
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• pp.80-87
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• 1985

Lithium dual complex grease was prepared through the second continuous saponification reaction of a complex gellant system whose essential components comprised of a selected hydroxy fatty acid, lithium hydroxide monohydrate and boric acid to have a fiber structure of chemical, thermal and mechanical stability at high temperatures. An optimum amount of complex gellant was found to be 14% (NLGI #2), and an addition of castor wax of 1.5% provided an excellent performance properties, especially. The oil separation, oxidation stability, water wash-out property, shear stability, extreme pressure and wear property of thus prepared were tested by the ASTM and KS methods, and a characteristic result was obtained.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2000.06a
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• pp.106-113
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• 2000

A pump which is a fundamental device in a hydraulic system affects on overall system performance to a great deal. Such problems as leakage and solid friction loss become important in field applications, especially for the case of operation under high pressure and at high speed. So the research on this kind of subjects is necessary to improve the performance of hydraulic devices. A high pressure radial piston pump is analyzed here, which has a stationary cylinder block. It pumps hydraulic fluid by letting camring push a piston in a cylinder. Fluid leaks between the piston and cylinder so that it deteriorates the pump efficiency. Furthermore, the piston happens to touch the cylinder wall to increase the friction loss and wear. In this research, by means of FDM, volumetric, mechanical and overall efficiencies are observed by varying several design Parameters and operation conditions. Design values or their trends are presented to improve these efficiencies.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1142-1147
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• 2011

The rail cant produces a wider bearing area between the wheel and the rail by moving the wheel-rail contact area away from the gauge towards the centre of the railhead, thus improving the wear pattern of the railhead and wheel treads. It is essential to keep the rail cant within the allowable range to ensure optimum track geometry. Neglecting the rail cant geometrical parameters in a track quality evaluation can cause safety of railway vehicle and serviceability problems. In this paper, we examined the effect of the rail cant in general geometry state of the railway track using VI-Rail and analyzed running safety when the railway vehicle passing through curves depending on change of the rail cant and running speed.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.43-46
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• 2003

To develop bevel gear dies that have characteristics of high precision and enough life time, the technology of die manufacturing and design which increase the resistance of wear and fatigue is essentially needed. Here in the study, we have investigated several materials for dies and electrode. And, the most economical and suitable electrode material has been selected through the characteristic analysis of electrode materials such as copper, graphite and chromium copper. With the help of CAD/CAM/CAE, the total manufacturing system of high precision electrode for bevel gear has been established.

• Journal of Fashion Business
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• v.11 no.4
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• pp.232-246
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• 2007

The purpose of this study is to investigate aesthetic characteristics and aesthetic consciousness of the style that European fashion(Paris, London, Netherlands) has accepted the since $19^{th}$ century. The mode Japonisme's development process in around $20^{th}$ century and 21st century has 6 characteristics as follows; 1. Accepting kimono as dressing gown 2. Accepting kimono as Japanese style's objet of Japanese taste 3. Accepting Japanese textile's skills, patterns, and asymmetry. 4. Accepting kimono's formative nature : flat pattern, flexibility, style etc. 5. Shocking of Japanese style's beauty 6. Accepting characters and casual wear Japanese aesthetic consciousness expressed on unconstructed design or deconstructed design that is the aesthetic characteristic of Japanese fashion is , , and the aesthetic consciousness expressed on Zen(Seon) style, cartoons of character fashion, and costume play is .

• Transactions of the Korean Society of Machine Tool Engineers
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• v.15 no.1
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• pp.32-38
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• 2006

The magnetic fluid polishing technique can polish the tool of complex shape, because the polishing method which polishes as compress the workpiece by the magnetism abrasives to arrange to the linear according to the line of magnetic force. Therefore, we producted the magnetic fluid polishing device in order that mirror like finishing processes the tool surface. In order to a polishing condition selection, polishing characteristic was estimated by polishing conditions which are magnetic flux density, polishing speed, grain size, magnetic fluid. The tool was polished to the selected polishing condition. The result to evaluate the polished tool's performance with the cutting force and tool wear, the polished tool's performance was improved compared with the tool not to polish.