• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.3
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• pp.111-117
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• 1997

The sudden-stop apparatus is made to measure the residual stress of the infinitesimal area at the turning work surface by using the X-ray stress apparatus. This study is trued to make the cutting work the instantaneous stopping state in the normal working state. The behaviour of work material near the tool is estimated. The estimation method is that the distribution of residual stress can be also measured. The object is to clarify and control the mechanism to leave the adequate stress of the finishing surface. It's beginning is due to observe the occurrence state of the residual stress at the cutting work. The result obtained by this study is as follows. The chips are not separated from the work materials at all the cutting experiments of built-up edges or the shearing areas etc. which can be precisely observed by using the sudden-stop apparatus. The strain of movable system which can be seen at the part of working layer means the size of strain. This experiment proves that the working strain should be lessened to make the size of strain control the residual stress happened at the cutting surface.

• Korean Institute of Interior Design Journal
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• v.21 no.3
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• pp.22-30
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• 2012

Nowadays the issue of environmental pollution and ecological destruction is not a simple issue but an important issue to be continuously considered. It is deemed that a study for recycled new materials is immediately required and this study is to analyze features and processing methods of new materials which can be used to interior space. We found the recycled new materials used for space through researching various web sits. And then we analyzed what the base materials are and classified that base materials are whether natural or artificial of the recycled materials. We classified processing methods of the recycled new materials after researching general processing methods. The result of this study would be an important material to the research and development of new finishing materials with consideration of environment and to the research for a guideline of applicable new materials. The results of this study are as follows : First, we could classify widely 2 categories into natural material and artificial material and then 10 subcategories into metal, glass, wood, rubber, stone, plastic, leather or fabric, ceramic, concrete and so on, and analyzed that which material is mostly used and whether it is single material or multiple material. In order to analyze the feature of processing method. Second, we could classify into 4 categories such as junction, surface process, molding, and insert, and found out which processing method is applied based on objects of research. Third, as an analysis result of the recycled new material feature, in order to develop various new materials, it is required to study on combination and application of 2 materials or more rather than single material. Four, as a analysis result of the processing method feature, I would like to suggest that development and application of various processing methods are required. Especially, it is necessary to grope for a way to develop new functional materials for interior space through a systemic research and analysis of processing method of other fields. Furthermore, a way to reuse recycled new materials should be considered in a stage of selection and application of processing method.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.77-89
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• 2018

In the case of fiber/rubber composites for tire applications, the interfacial adhesion between fiber and rubber significantly affects the physical properties of the finished products. Generally, organic synthetic fibers used for tire cords are treated with resorcinol formaldehyde latex(RFL) primer on the surface of the fiber to improve the adhesion to rubber. Changes of adhesion between rubber and tire cords might weaken as temperature rises due to overheating of car engine and friction with road. In this study, the effects of temperature on the primer treated polyketone cord/rubber composites and the changes in interfacial adhesion were investigated. Polyketone cord/rubber composites were prepared after RFL solution treatment on the surface of polyketone fibers. After that, composites was thermally aged at different temperature conditions(60, 80, 100, $120^{\circ}C$) and times(1, 5, 10, 15days). The adhesion strength of polyketone cord/rubber composite treated with RFL primer was higher than untreated composite by more than 3 times. After heat aging, the adhesion strength of untreated polyketone cord/rubber composites increased while the RFL treated polyketone cord/rubber composites decreased somewhat.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.118-122
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• 2010

The interest in textile which has far-infrared ray emissive property has been increased in the field of biophysics and medicine. In this study, far-infrared ray emissive polyurethane nano-web was obtained using electrospinning of polyurethane(PU) solution mixed with ceramics powder and far-infrared ray emissive properties of nano-web were evaluated by measuring far-infrared ray emission power and emissivity(%). To investigate the influence of concentration of ceramics powder in PU solution and temperature for far-infrared ray emissive properties, far-infrared ray emissivity was measured at varied temperature using various nano-web including varied concentration of ceramics powder. Polyurethane nano-web was characterized by SEM to observe the deposition of ceramics powder on polyurethane nano-web surface. The far-infrared ray emissivity was increased with the concentration of ceramics powder in the nano-web. The far-infrared ray emission power was enhanced with increasing temperature of the samples; however, far-infrared ray emissivity was decreased with increasing temperature because the increase of emission power of ceramic containing nano-web was lower than the emission power of black body one.

• Textile Coloration and Finishing
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• v.19 no.2
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• pp.32-35
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• 2007

Cyclodextrin is a cyclic oligosaccharid material which shows an ability to incorporate organic guest molecules inside their cavity area. Thus, this ${\beta}-cyclodextrin$ treatment on fiber substrates may provide the changed surface characteristics of the substrates such as solubility, chemical reactivity and spectral property. In this context, the aim of this present work is to make a bridge connection using hetero-bi-functional reactive dye between fiber substrates and ${\beta}-cyclodextrin$. In addition, the corresponding Berberine inclusion behaviors into the inner cavity of ${\beta}-cyclodextrin$ was examined. The %exhaustion of Berberine inclusion as a guest molecule within the ${\beta}-cyclodextrin$ was measured using UV-Vis spectrophotometer. The findings showed that the %exhaustion of Berberine inclusion increased with increasing the prepared dye bridge compound and ${\beta}-cyclodextrin$ host material.

• Textile Coloration and Finishing
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• v.20 no.1
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• pp.44-47
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• 2008

Organic semi-conductive materials have characteristics such as the advantages of easy formability, low-cost and diversity along with moderate semi-conductive properties. In this paper, we developed a flexible organic-inorganic hybrid solar cell fiber. First, we made a solar cell on the glass and attached the solar cell on the glass fiber similarly. In the latter case, thermal deposition method was employed in order to effectively apply ITO onto fiber surface. The amount of ITO was controlled by varying the temperature from 25, 150 to $300^{\circ}C$. Optimum result was obtained at $150^{\circ}C$ where maximize the deposition amount without significant decomposition of ITO. Despite of maximum open circuit voltage of 0.39V, the resulting current was quite unstable and weak, limiting realistic applications. It was, however, concluded that the flexible solar cell fiber developed showed a possibility of low-weight application from functional clothing for military to space suit mainly due to flexibility and thus wear ability.

• Textile Coloration and Finishing
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• v.21 no.6
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• pp.1-11
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• 2009

Super-hydrophobic surface, with a water contact angle greater than $150^{\circ}$, has a self cleaning effect termed 'lotus effect'. We introduced super-hydrophobicity onto aramid/rayon mixture fabric with dual-scale structure by assembling silica nano-sol. Mixture fabric was treated with silica nano-sol, fluoric polymer using various parameters such as particle size, concentration. Silica nano-sol size were measured using particle size analyzer. Morphological changes by particle size were observed using field emission scanning electron microscopy(FE-SEM), contact angle measurement equipment. The contact angle of water was about $134.0^{\circ}$, $137.0^{\circ}$, $143.0^{\circ}$, $139.5^{\circ}$ and $139.0^{\circ}$ for mixture fabric coated with 100.2nm, 313.7nm, 558.2nm, 628.5nm and 965.4nm silica nano-sol, compared with about $120.0^{\circ}$ for mixture fabric coated with fluoric polymer. When we mixed particle sizes of 100.2nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $146.2^{\circ}$. And we mixed particle sizes of 313.7nm and 558.2nm by 7:3 volume ratio, the contact angle of water was about $141.8^{\circ}$. Also we mixed particle sizes of 558.2nm and 965.4nm by 7:3 volume ratio, the best super-hydrophobicity was obtained. In this paper, we fabricated the water-repellent surfaces with various surface structures by using four types of silica nano-sol, and we found that the dual-scale structure was very important for the super-hydrophobicity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.61-64
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• 1995

Grinding has been adapted as a finishing process,which can carry out form and surface integrity at the same time. Recently, high efficient and precise grinding technique is required bacause the needs for functional parts such as silicon wafer,ceramic,and electric materials are increasing. Accordingly, the development of grinding wheel appropriate to that purpose is very important. So, in this paper we newly developed a diamond grinding wheel by applying the superior characteristics of spheroidal graphite of the cast iron sintered product. Especially, a electric resistance sintering method was applied in which rapid heat treatment is possible. Finally, we have achieved successful results that the grinding wheel has high hardness,durability and grinding ability,and satisfies above conditions.

• Architectural research
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• v.7 no.1
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• pp.19-26
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• 2005

Unlike other countries, Korea uses various kinds of wall-paper as finishing material. Conventional wall-paper consists of paper and vinyl, and petrochemical ink is used for the decoration of the surface. Adhesive is used to paste the wall with the wall-paper, which emit substantial amounts of VOCs and formaldehyde. In this study, VOCs characteristics emitted from specimens made of concrete, mortar, gypsum board and wall-paper were investigated using small chamber method. Moreover, concentration and emission factor of BTEX(Benzene, Toluene, Ethylbenzene, m,p,o-Xylene) and TVOC were investigated, and concentration and emission factor decay were estimated. As a result of the prediction, both time-dependent concentration decay and cumulative concentration can be converted into the logarithmic scale. Furthermore, prediction equations were developed from the experimental results under accurately controlled experimental conditions. Therefore, there may be difference if the estimated equations are directly applied to real buildings. Further research should be done on the generalization of the developed prediction equations.

• Journal of Welding and Joining
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• v.22 no.2
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• pp.46-50
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• 2004

In today's highly competitive marketplace, it is of great significance for the manufacturing industry to reduce lead-time and costs fur the product development. Since first emerged in 1986, Rapid Prototyping (RP) technology has helped successfully to reduce time and costs. Recently, RP using functional materials such as metal has been researched. However RP using the molten metal has been struggling to resolve several drawbacks, such as dimensional inaccuracy, poor surface finish, post finishing, etc., that originate primarily from the overall deposition of molten metal for each layer. So, the purpose of this study is to develop a new RP technique using sheet metal and projection welding for reducing several drawbacks in occurring RP using molten metal. Also tensile and bending specimens were made by the developed RP process using projection welding and were verified.