• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.585-590
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• 1997

Conventional foaming process has defects such as lower mechanical properties than ur~foaming material due to non-uniform cell distribution and environmental pollution problem caused by chemical blowing agency. So, a new foaming process such as Microcelluar plastics has been introduced to use inactive gases as a foaming agency. In order to apply Microcellular plastics for mass production process system such as extrusion, injection molding and blow molding, it needs to predict the change in material properties of polymer according to the amount of meltingas. In Polymer molding applying Microcelluar plastics, the change of viscosity among several material properties is the most important factor. Therefore, this paper is aimed to establish the method which not only finds out but also predicts the change of viscosity of ABS(Acrylonitri1e Butadiene Styrene) resin according to inert gas amount in extrusion molding.

• Tribology and Lubricants
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• v.16 no.1
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• pp.1-8
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• 2000

Friction and wear tests have been performed on nylon, acetal resin, and PTFE (polytetrafluoroethylene), in reciprocating dry sliding conditions against steel discs. According to the results, acetal resin showed the lowest wear rates and PTFE exhibited the lowest friction coefficient. The prominent wear mechanisms found were adhesion and abrasion.

• Journal of the Korean Society of Safety
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• v.22 no.3 s.81
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• pp.22-27
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• 2007

The knowledge of the flash point of the various liquid substances is required because of process safety and control in industrial fire protection. The epoxy resin is one of versatile resins that has wide selection of using curing agents and additives to achieve various applications such as coatings, adhesives, interior materials, reinforced plastics and electrical insulation. In this study, the lower flash points for p-xylene+epoxy resin, o-xylene+epoxy resin and n-butanol+epoxy resin systems were measured by using Pensky-Martens closed cup tester. The lower flash points for p-xylene+epoxy resin, o-xylene+epoxy resin and n-butanol+epoxy resin systems rapidly increased 80wt%, 90wt% and 95wt% of epoxy resin concentration, respectively. This results serve as a guide to estimate flash point of any epoxy resin solution.

• Design & Manufacturing
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• v.15 no.2
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• pp.1-10
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• 2021

In this study, the current state of the plastics industry has been examined. The direction of development and innovation is reviewed and commented. The technical statuses of various sectors such as thermoplastic resin, composite material, mold engineering, and simulation have been scrutinized. In addition, the industrial status of each sector has been reviewed. Then, the challenges that the plastics manufacturing industry has to deal with have been discussed. Especially, the situation in Republic of Korea has been elaborated in detail. Based on the discussion, an open innovation strategy has been suggested. It has been argued in this work that the open innovation strategy will enables efficient funding and development by avoiding resource consuming rent seeking.

• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.2
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• pp.141-147
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• 2014

A nondestructive ultrasonic technique was applied to evaluate the thermal characteristics and degradation of synthetic polymer resin (plastics) with better cost-effectiveness and functionality than glass and metal. Thermoplastic and transparent acrylic resin (PMMA) specimens were annealed at below the glass transition temperature ($T_g$), and the propagation characteristics (attenuation and velocity) were measured. The attenuation increased and the velocity decreased with thermal degradation. The results showed that the thermal aging of the specimens could be evaluated quantitatively and that the Tg could be evaluated qualitatively.

• Resources Recycling
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• v.26 no.1
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• pp.69-77
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• 2017

Used small household appliances(small e-waste) consists of a variety of complex materials and components. The small e-waste is mainly composed of plastics and an important potential source of waste plastic. The black plastics, particularly are very difficult to separate by resin type and therefore these are mainly recycled in the form of a mixtures. In the present study, the sorting technologies such as gravity and electro static separation, near-infrared ray(NIR) and IR/Raman optical sorting separation on mixture of black plastics were analyzed and their limitations on sorting process were also investigated. The Laser Induced Breakdown Spectroscopy(LIBS) spectrum of each black plastics was used for identification of black plastics by resin type, and after analyzing the normalization operation, Principal Component Analysis(PCA) was carried out. The spectrum data was optimized through PCA process. In order to improve the identification accuracy and sorting efficiency of black plastics, it is necessary to design a classifier with high efficiency and to improve the performance and reliability of the classifier by applying the field of intelligent algorithms.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.235-238
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• 2003

Thermo-plastic has generally bad electrical characteristics at high temperature comparing to thermoset-plastics when the plastic apply to electrical power apparatus as an electrical insulator. To solve the problem, we study engineering plastics such as Polyamide and Polyphthalamide as a base resin. And filler of the engineering plastics is glass fiber. Electrical characteristics studied are permittivity, loss factor and breakdown strength according to temperature and frequency of measuring signal. Electrical characteristics of Polyphthalamide has good temperature and frequency dependency comparing to those of Polyamide.

• Advanced Composite Materials
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• v.16 no.2
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• pp.181-194
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• 2007

This paper presents the mechanical properties of a composite consisting of acrylonitrile-butadiene-styrene (ABS) resin mixed with carbon fiber reinforced plastics (CFRP) pieces (CFRP/ABS). CFRP pieces made by crushing CFRP wastes were utilized in this material. Nine kinds of CFRP/ABS compounds with different weight fraction and size of CFRP pieces were prepared. Firstly, tensile and flexural tests were performed for the specimens with various CFRP content. Next, fracture surfaces of the specimens were microscopically observed to investigate fracture behavior and fiber/resin interface. Finally, the tensile modulus and strength were discussed based on the macromechanical model. It is found that the elastic modulus increases linearly with increasing CFRP content while the strength changes nonlinearly. Microscopic observation revealed that most carbon fibers are separated individually and dispersed homogeneously in ABS resin. Epoxy resin particles originally from CFRP are dispersed in ABS resin and seem to be in good contact with surrounding resin. The modulus and strength can be expressed using a macromechanical model taking account of fiber orientation, length and interfacial bonding in short fiber composites.

• Journal of Ocean Engineering and Technology
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• v.23 no.2
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• pp.98-103
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• 2009

The resin infusion method is the latest technology of FRP laminating and cleaning to improve FRP hull quality. This method is focused on how to arrange infusion channels for the laminiating strategy. The laminating strategy using the resin infusion method has been utilized to complete the infusion work and remove the cavities on the FRP surface within the curing time. It is resulting from the arrangement of infusion and vacuum channels, the resin property, and the combination of FRP. This strategy has been depended on the field experience for manufacturing FRP without the resin infusion simulation. This study can help to improve the efficiency of FRP fabrication with the laminating strategy including the resin infusion simulation instead of the field experience.

• Proceedings of the Korean Reliability Society Conference
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• 2005.06a
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• pp.303-305
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• 2005

Recently, various plastics are used for improvement of reliability and thermal stability of electronic goods. But, it is difficult to choose suitable balance of grade resin to each other product property. Selection of high efficiency resin is becoming inescapable circumstance according to change of reflow temperature of product and development of product following to lead free. Using a inexpensive and reasonable resin, that sustain a uniform performance of product quality. It is make a robust product and increase a company's competitive power. Hereupon, I introduce example that use ESPI methods of thermal deformation analysis of product using in our company product. I try to refer to a structural weak point detection of real time measurement of electronic parts instead of mechanical and chemical measurement of specimen type.