• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 추계학술대회 논문집
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• pp.763-766
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• 2000

Rapid Prototyping(RP) techniques have their unique characteristics according to the working principles: stair-stepped surface of parts due to layer-by-layer stackin, low build speed caused by line-by-line solidification to build one layer, and additional post processing to improve surface roughness, so it is required very high cost to introduce and to maintain RP apparatus. The objective of this study is to develop software for automatic generation of unit shape part (USP) for a new RP process, Variable Lamination Manufacturing using linear hotwire cutting technique and expandable polystyrene foam sheet as part material (VLM-S). In order to examine the applicability of the developed software to VLM-S, USP's of general three-dimensional shapes, such as an auto-shift lever knob and a pyramid shape were generated.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1316-1319
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• 2003

The micromovements and stress distributions of cancellous bone in dental implant system play important roles in evaluating chewing function of an implant system. The micromovements and stress distributions in dental implant system generally depend on the chewing force and bone properties. Three dimensional nonlinear finite element analysis has been employed to investigate this issue quantitatively. Chewing forces and bone properties are classified into several groups and three types of implants involving one classical cylindrical type and two expandable implants are investigated in this paper.

• 한국CDE학회논문집
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• 제8권4호
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• pp.212-221
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• 2003

In order to reduce the lead-time and cost, the technology of rapid prototyping (RP) has been widely used. A new rapid prototyping process, transfer-type variable lamination manufacturing process by using expandable polystyrene foam (VLM-ST), has been developed to reduce building time, apparatus cost and additional post-processing. At the same time, VLM Slicer, the CAD/CAM software for VLM-ST has been developed. In this study, algorithms for accuracy improvement of VLM-ST, which include offset and overrun of a cutting path and generation of a reference shape are developed. Offset algorithm improves cutting accuracy, overrun algorithm enables the VLM-ST process to make a shape of sharp edge and reference shape generation algorithm adds additional shape which makes off-line lamination easier. In addition, proposed algorithms are applied to practical CAD models for verification.

• Journal of Chest Surgery
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• 제28권2호
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• pp.201-205
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• 1995

Most of the patient with endobronchial tuberculosis have some degree of bronchial stenosis. however, a part of bronchial stenosis need aggressive treatment for the patency because of severe symptoms. The self-expendable metallic stents provide palliative treatment for narrowed airways where surgical resection is inadvisable. We experienced a successful left wedge pneumonectomy on a 29-year-old woman with obstruction of left main bronchus due to complication of the bronchial stent. She had inserted self-expendable metallic stents on left main bronchus of the tuberculous bronchial stenosis two times. There was no specific postoperative complication.

• 전자공학회논문지B
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• 제30B권6호
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• pp.86-92
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• 1993

In this paper, we present a VLSI chip design of Multi-layer Bidirectionsl Associative Memory with good error-correction performance. The MBAM neural chip utilizes inner product implementation schems with binary storage and analog calculation.. Multi-layer can be constructed by direct cascading of these chips, and the number of neurons is expandable by parallel connection of these chips. We made proto-type chips and interface board to test the expansion. Currently the Chip has 32 input nodes, 32 output nodes, and can store up to 48 patterns, 32x48x2 SRAMs are included in the chip.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.937-940
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• 2000

This paper describes expandable 4 bit ALU IC using adiabatic and dynamic CMOS circuit technique. It was designed so that the integrated circuit may have the function which is equivalent to HC181 which is CMOS standard logic IC for the comparison, and it was fabricated using a standard 1.2${\mu}$ CMOS process. As the result, the IC has shown that it operates perfectly on all function modes. The power dissipation is 2 order lower than that of HC 181.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2013년도 추계학술대회 초록집
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• pp.221-222
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• 2013

다양한 첨가제가 들어가는 고분자 화합물(compound)의 제조에 있어 난연 발포 보조제인 팽창흑연(Expandable Graphite, EGP)은 흡유가가 낮기 때문에 비교적 많은 양을 첨가해도 혼합(Mixing)이 잘 되는 것으로 알려져 있다. 본 논문에서는 대표적인 인계 난연제 APP(Ammonium Polyphosphate)를 사용한 난연 EPDM(Ethylene Propylene Diene Monomer) 폼에 팽창흑연 첨가량을 증가시키면서 산소 지수와 발열량을 통해 난연 성능의 변화를 분석하였다. 산소지수는 ISO 4589-2 상온 산소지수 방법을, 발열량 평가는 ISO 5660-1 콘 칼로리미터를 활용하였다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 춘계학술대회 논문집
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• pp.69-71
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• 2003

This paper introduces TRIZ. TRIZ is the theory of inventive problem solving which haws started by G.Altschuler since 1946, Russia. TRIZ is applicable for not only mechanical engineering, but also science, economic and pedagogy fields. Characteristics of some kind of softwares for TRIZ method are briefly reviewed Especially Catia with IMC TechOptimizer is studied in detail and it is expected to be applicable well for the Ocean Engineering fields, if applicably applied for IM-Principles, IM-Predictions and IM-Effects, even though it will need much efforts and time to study. As an application example of TRIZ, Self-expandable anchor which is pending for patent is presented briefly.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.942-945
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• 2005

The purpose of this study is to suggest a fundamental data for change of dynamic properties according to the loading time of resilient materials. 18 kinds of resilient materials included 4 representative types were measured at the load time of 24hours and 2hours by the method of Korea standard (KS F 2868) measuring the dynamic stiffness and the loss factor of materials under floating floors. As a result, the dynamic stiffness was increased rapidly in case of expandable polystyrene and rubber materials according to the load time, especially before 2 hours. The loss factor was represented that rubber materials with high elasticity are high, and expandable polystyrene, polyester, poly ethylene materials with low elasticity are low.

• Elastomers and Composites
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• 제55권4호
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• pp.314-320
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• 2020

This study focused on experiments with polyethylene glycol (PEG) and glycidyl methacrylate (GMA), which are functional additives for water-expandable rubber. Polychloroprene rubber (CR)/superabsorbent polymer (SAP) composites were prepared and their cure behaviors, mechanical properties, water absorption rates, and surface morphology were measured based on the functional additives applied. When PEG and GMA were applied to the composites, the water absorption rate increased-including the initial rate-compared to that measured when functional additives were not used. The results also show that PEG has a hydrophilic functional group, which allows it to absorb more water, and GMA acts as a coupling agent between CR and SAP. However, with the introduction of functional additives, the cure rate slowed down and the mechanical properties also decreased.