• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.983-987
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• 2001

This paper deals with an automated computer-aided process planning system by which designer can determine operation sequences even if they have little experience in process planning of wheel bolt products by a multi-stage former. The approach to the system is based on knowledge-based rules and a process knowledge base consisting of design rules is built. Knowledge for the system is formulated from plasticity theories, empirical results and the empirical knowledge of field experts. Programs for the system have been written in AutoLISP for the AutoCAD using a personal computer and are composed of two main modules. An attempt is made to link programs incorporationg a number of expert design rules to form a useful package. Results obtained using the modules enable the designer and manufacturer of wheel bolt product to be more efficient in this field.

• 소성∙가공
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• 제16권1호
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• pp.67-74
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• 2007

This study is aimed to find out the optimal forming conditions by comparing and analyzing material flow, deformation pattern, and a forming load through rigid-plastic FEM for a flange using pipe. Flanges are widely used for various purposes as connectors of industrial steel pipes which are manufactured by drawing process. The forming feature of flange was reviewed through both heading process and radial extrusion process in a cold working condition. As a result of simulation, the shape of flange can not be made by heading process, but made by radial extrusion process. The effects of design factors, such as gap-height, die-comer radius, and frictional factors on maximum forming load and deformation pattern are investigated for radial extrusion process.

• 한국재료학회지
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• 제27권11호
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• pp.597-602
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• 2017

In this study, an Al-0.7wt%Fe-0.2wt%Mg-0.2wt%Cu-0.02wt%B alloy was designed to fabricate an aluminum alloy for electrical wire having both high strength and high conductivity. The designed Al alloy was processed by casting, extrusion and drawing processes. Especially, the drawing process was done by severe deformation of a rod with an initial diameter of 12 mm into a wire of 2 mm diameter; process was equivalent to an effective strain of 3.58, and the total reduction in area was 97 %. The drawn Al alloy wire was then annealed at various temperatures of 200 to $400^{\circ}C$ for 30 minutes. The mechanical properties, microstructural changes and electrical properties of the annealed specimens were investigated. As the annealing temperature increased, the tensile strength decreased and the elongation increased. Recovery or/and recrystallization occurred as annealing temperature increased, and complete recrystallization occurred at annealing temperatures over $300^{\circ}C$. Electric conductivity increased with increasing temperature up to $250^{\circ}C$, but no significant change was observed above $300^{\circ}C$. It is concluded that, from the viewpoint of the mechanical and electrical properties, the specimen annealed at $350^{\circ}C$ is the most suitable for the wire drawn Al alloy electrical wire.

• 한국실내디자인학회논문집
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• 제21호
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• pp.165-172
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• 1999

For the useful method capable of modern expression on traditional residence architecture, a study was performed on the methodological establishment and possibility of typological method could be examinated to interior design process by typological method. First of all, through the establishment verbal of our Korean traditional architecture and further investigation of environmental and cultural idealogical facts, it could be extracted from natural instinct, duality, continuance, flexibility and transitiov. In second process, based on these results, it could be framed and described the individual typological language and, for the sake of drawing for visual and spatial typology, it was made by sketch in terms and view of possibile guidance of prototype, transforming and application method. from these results of investigated sketches, it cold be used for criteria of application method as the parts of visual and spatial typological elements to have an applicable expression of it/s traditionality. Based on above facts, for the subjects of spatial system, form & shape system, circulation system, order system, decoration system, color & material system in interior design fields, we cold propose the practical possibility through the consideration of application method for built-in meaning that could be adaptable for the interior design practices. These facts were extracted from the based on visual & spatial typology, as above mentiov. Also, through preparing and suggesting the criteria of evaluation and measurement of design quality , we could propose the applicable methodology for further & basically Korean traditional embodiment.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.159-163
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• 2006

The effects of annealing temperature and time on mechanical properties and microstructures were studied in cold drawn pearlitic steel wires containing 0.84wt% Si. Annealing was performed from $200^{\circ}C$ to $450^{\circ}C$ with different time of 30sec, 1min, 15min and 1hr. The increase of tensile strength at low temperature was related with strain ageing. The decrease of tensile strength at high annealing temperature was related with spherodization of cementite and the occurrence of recovery of the lamellar ferrite in the pearlite. The improvement of ductility was connected with spherodization of cementite plate in pearlite and recovery process by reduction of high dislocation density at short time annealing temperature of $400^{\circ}C$.

• 소성∙가공
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• 제14권7호
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• pp.613-618
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• 2005

The paper is concerned with the process design and the die design for manufacturing the preform of a large pressure vessel. The cold-working processes are introduced to improve the fatigue strength and to simplify the manufacturing process. By the finite element simulation, the parameter design is carried out, which is subjected to constraints such as the blank sire, press capacity and other minor limitations. The proposed design results are verified by the model experiments, in which the model is scaled down to one tenth of the original size.

• Journal of Platform Technology
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• 제11권1호
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• pp.60-71
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• 2023

전세계적으로 반려인이 꾸준히 증가하고 있고, 반려동물에 대한 사회적 인식이 '가족'의 일원으로 변하면서 반려동물 산업도 다양한 방식으로 발전 및 성장하고 있다. 반려동물은 건강에 문제가 있어도 표현할 수 없어 질병이 악화하는 경우가 많아 IoT 기술을 활용해 건강 변화를 조기에 확인할 수 있는 펫테크 헬스케어시장도 주목받고 있다. 본 연구에서는 반려동물 헬스케어 시장에 대한 조사 및 선행연구를 분석하여 확대되는 반려동물 헬스케어 시장에 서비스디자인이 이러한 문제 인식을 바탕으로 반려동물 헬스케어 시장에서 중요한 동물 검체 운반 서비스 개발에 관여하여 콜드체인 서비스 시장을 활성화할 수 있고, 향후 확장된 반려동물 헬스케어 시장에서 반려인, 반려동물, 동물병원 등의 다양한 이해 관계자가 모두 만족할 수 있는 솔루션 개발에 방향을 제시하고자 한다.

• Design & Manufacturing
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• 제12권3호
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• pp.60-65
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• 2018

The production of the automotive parts with the ultra high strength steel usually involves large amount of springback as well as fracture during the cold stamping process. Variable blank holding force(VBHF) can be used as one of the effective process parameters to reduce the springback amount with achieving better condition of formability. In this paper, VBHF with respect to the punch stroke is applied to the stamping process of the front side rear lower member for reducing the springback amount. From the analyses with constant blank holding force(CBHF), 24 kinds of VBHF conditions are utilized to investigate the springback tendency. It is noted that springback can be effectively reduced when BHF is increased near the bottom dead center because VBHF provides the tensile force to the blank with an adequate level of deformation without fracture.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.137-138
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• 2009

There is a growing interest to replace the commercial steels with non-heat treated steels, which does not involve the spheroidization and quenching-tempering treatment in the steel-wire industry production. However, non-heat treated steels should satisfy high strength and good formability without performing heat treatment. Therefore, it is important to investigate optimum materials showing a good combination of strength and formability after the cold drawing process. In this presentation, non-heat treated steel wire rod produced by POSCO will be introduced and discussed on detail technical concepts.

• 소성∙가공
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• 제11권5호
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• pp.430-438
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• 2002

This paper suggests the new technology to control metal flow in orther to change of the cold forging from conventional deep drawing forming. This technology can be summarized the complex forming, which consists of bulk forming and sheet forming, and multi-action forging, which be performed double action press. The proposed technology is applied to hub clutch model which is part of auto-transmission for automobile. The purpose of this study is to investigate the material flow behavior of hub clutch through control the relative velocity ratio and the stroke of mandrel and punch using the flow forming technique. First of all, the finite element simulations are applied to analyse optimal process conditions to prevent flow defect(necking defect etc.) from non-uniform metal flow, then the results are compared with the plasticine model material experiments. The punch load for real material is predict from similarity law. Finally, the model material experiment results are in good agreement with the FE simulation ones.