• 산업기술연구
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• 제35권
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• pp.3-8
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• 2015

A study has been made on defects which are formed in manufacturing processes of engine bearing and also on fatigue crack growth behavior in each step of bearing metal manufacturing. After the first step(sinter brass powder on steel plate ; Series A) many voids are made on brass surface and its size is decreased by the second step(rolling process of sintered plate ; Series B). After the third step(re-sintering step of brass powder and rolling ; Series C) the number of voids is decreased and its type shows line. The time of fatigue crack initiation and the growth rate of fatigue crack are in order of Series A, Series B, Series C. These reasons are that void fosters the crack initiation and growth, and residual stress made by rolling process effects on the crack growth rate in Series B, C. In forming and machining processes by use of final bearing metal, crack was observed at internal corner of flange and peeling off was observed at junction between steel and brass. Owing to the above crack and peeling off, it is considered that there is a possibility of fatigue fracture during the application time.

• 산업기술연구
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• 제31권A호
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• pp.45-51
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• 2011

A study has been made on defects which are formed in manufacturing processes of engine bearing and also on fatigue crack growth behavior in each step of bearing metal manufacturing. After the first step (sinter brass powder on steel plate ; Series A) many voids are made on brass surface and its size is decreased at the second step (rolling process of sintered plate ; Series B). After the third step (re-sintering step of brass powder and rolling ; Series C) the number of voids is decreased and its type shows line. The time of fatigue crack initiation and the growth rate of fatigue crack are in order of Series A, Series B, Series C. These reasons are that void fosters the crack initiation and growth, and residual stress made by rolling process affects on the crack growth rate in Series B, C. In forming and machining processes by use of final bearing metal, crack was observed at internal corner of flange and peeling off was observed at interface between steel and brass. Owing to the above crack and peeling off, it is considered that there is a possibility of fatigue fracture during the application time.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2007년도 제33회 하계학술대회 초록집
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• pp.264-264
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• 2007

• 대한산업공학회지
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• 제21권3호
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• pp.441-461
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• 1995

This research proposes an Integrated Product Information Model (IPIM) using STEP (Standard for the Exchange of product model data) for Computer Integrated Manufacturing (CIM) of Concurrent Engineering (CE). IPIM is based on Geometry and Topology (STEP Part 42), Form Feature (STEP Part 48), and Tolerance (STEP Part 48) for representing the integrated information of mechanical parts. For the IPIM, 1) new entities are developed for integration of existing entities, and 2) the existing entities are restructured and modified for a special application protocol. In CIM or CE, the advantages of using IPIM having integrated form of geometry, feature and tolerance are 1) integration of product design, process design and manufacturing sequentially or concurrently. 2) keep the product data consistency, modified by different domain, and 3) automatic data exchange between different application software and different hardware. The prototype system is composed of CAD, Data Probe, DBMS and SDAI (Standard Data Access Interface), and the generated STEP data is stored in a step file of DBMS for other applications.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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• pp.257-264
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• 2004

분산 제조 시스템간의 협업을 가능케 하는 e-Manufacturing paradigm 의 성공을 위해서는 CAD-CAM-CNC chain 의 제조 분야뿐만 아니라 SCM, ERP, CRM 등의 상위 시스템과의 제품 및 가공 정보의 원활한 흐름이 필수적이다. STEP 과 STEP-NC 는 이를 해결할 표준으로 자리매김 할 것으로 기대되고 있다. 본 논문은 STEP-NC 의 국내 promotion 차원에서 참고문헌 [1]의 밀링용 파트프로그래밍 소개에 이어: 1) 선반용 데이터 모델, 2) 선반용 파트 프로그램의 작성 방법, 3) XML 을 이용한 파트 프로그램의 표현 방법들을 소개하고, 4) STEP-NC 기반의 생산 환경 구축을 위한 방안을 기술하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.525-526
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• 2007

Over-polishing is required to completely remove the material of top surface across whole wafer, in spite of a local dishing problem. This paper introduces the two-step CMP process using protective layer and high selectivity slurry, to reduce dishing amount and variation. The 30nm thick protective oxide layer was deposited on the pattern, and then polished with low selectivity slurry to partially remove the projected area while suppressing the removal rate of the recessed area. After the first step CMP process, high selectivity slurry was used to minimize the dishing amount and variation in pattern structure. Experimental result shows that two-step CMP process can be successfully applicable to reduce the dishing defect generated in over-polishing.

• 동아시아식생활학회지
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• 제2권1호
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• pp.133-138
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• 1992

The research on the manufacturing procedure of Hosanchun jun in the classical literature(17 kinds) showed that the most usually brewed rice wine in it is the 3rd step rice wine, which is brewed by adding rice wine base to it at the intervals used quantity are as follows. Nonglutinous rice(88.2%), flour(82.3%), and nu-ruk(100%) are used in the 1st step of brewing, and nonglutinous rice(82.3%), glutinous rice(17.6%), flour(23.5%), and nu-ruk(11.3%) are used in the 2nd sep, and glutinous rice, flour, and 3rd step of brewing. The grains are used in the form of -paste(88.2%) in the 1st, and in the form of paste(64.7%) and steamed water-soaked rice(sul-bab)(29.4%) in the second step, and sul-bab(64.7%) in the 3rd step of brewing. Nu-ruk is used in small quantity in the 3rd step but it is used I somewhat larger quantity in the 2nd step of brewing.

• 대한조선학회논문집
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• 제31권3호
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• pp.38-46
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• 1994

통합 생산 시스템의 역할은 제품의 전 생명주기에 걸쳐 필요한 다수의 응용 프로그램을 통합하는 것이다. STEP은 독립적으로 개발된 응용 프로그램의 통합을 쉽게 하기 위하여 정보모델과 인터페이스를 정의하는 국제 표준화 작업이다. STEP을 이용한 조선 통합생산시스템(CIMS)에서 정보모델은 EXPRESS로 정의되어 있으며, 이 정보모델은 데이타베이스의 스키마로 번역되어 진다. 논문에서는 조선공정계획 시스템에 포함된 두개의 응용 프로그램(즉, 블럭분할 시스템과 탑재 시스템)을 이용하여 개발된 프로토타입의 운용을 설명한다. 예로서 본 논문에서는 관계형 데이타베이스(Oracle)에 저장되어 있는 실제의 데이타를 보여준다.

• 한국표면공학회지
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• 제43권1호
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• pp.17-24
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• 2010

In this study, surface characteristics of dental implant fixture with various manufacturing process have been researched using electrochemical methods. The dental implant fixture was selected with 5 steps by cleaning, surface treatment and sterilization with same size and screw structure; the 1st step-machined surface, 2nd step-cleaned by thinner and prosol solution, 3th step-surface treated by RBM (resorbable blasting media) method, 4th step-cleaned and dried, 5th step-sterilized by gamma-ray. The electrochemical behavior of dental implant fixture has been evaluated by using potentiostat (EG&G Co, 2273A) in 0.9% NaCl solution at $36.5{\pm}1^{\circ}C$. The corrosion surface was observed using field-emission scanning electron microscopy (FE-SEM) and energy dispersive x-ray spectroscopy (EDS). The step 5 sample showed the cleaner and rougher surface than step 3 sample. The step 5 sample of implant fixture treated by RBM and gamma sterilization showed the low corrosion current density compared to others. Especially, the step 3 sample of implant fixture treated by RBM was presented the lowest value of corrosion resistance and the highest value of corrosion current density. The step 3 sample showed the low value of polarization resistance compared to other samples. In conclusion, the implant fixture treated with RBM and gamma sterilization has the higher corrosion resistance, and corrosion resistance depends on the step of manufacturing process.

• 한국품질경영학회:학술대회논문집
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• 한국품질경영학회 2006년도 추계 학술대회
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• pp.157-163
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• 2006

There are big differences in six sigma applications between manufacturing processes and transactional processes. This paper analyzes the differences between two areas by examining 18 six sigma case studies in Korean companies. To characterize six sigma cases, a step-by-step checklist is developed based on 12-step DMAIC methodology proposed by US six sigma academy. On the basis of those characterized data, the differences between two areas are analyzed. The most significant differences is that statistical tools are widely used in manufacturing processes, but qualitative tools are used in transactional processes during improvement phase.