• 해양환경안전학회지
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• 제26권6호
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• pp.732-741
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• 2020

최근 환경규제가 강화됨에 따라 액화천연가스(Liquefied Natural Gas)를 이용하여 전력을 생산해내는 신규발전설비인 부유식 LNG 발전설비(floating LNG power plant)가 개발되고 있다. 부유식 LNG 발전설비는 운용 시 증발가스가 발생하고 이를 제거하거나 회수할 수 있는 시스템의 설계가 필요하다. 그러나 해양플랜트는 해상요건에 따라 설계가 상이하고, 부유식 LNG 발전설비의 설계 전 시행착오를 줄이기 위해 지속적으로 수정이 가능한 BOG 회수시스템 공정모사 모델이 필요하다. 따라서 본 연구에서는 상용공정시뮬레이션 프로그램을 통해 부유식 LNG 발전설비에 적합한 모델을 모델링하고자 냉매사용 유무에 따라 서로 다른 BOG(Boil-Off Gas) 회수시스템을 모델링하여 BOG의 회수율과 액화점을 비교 및 분석하였으며, 그 결과 질소냉매를 사용한 BOG 회수시스템 모델을 부유식 LNG 발전설비용 BOG 회수시스템 모델로 제안하고자 한다.

• The Journal of Asian Finance, Economics and Business
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• 제8권10호
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• pp.87-95
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• 2021

This study aims to demonstrate the impact of BPR in reducing cost in international business organizations by analyzing the impact of decentralization, re-engineering organizational structures, re-engineering human resources, industrial process technology, improving total quality standards, and value engineering. The study population includes all the international business organizations operating in the Middle East, with the condition that they operate in at least four countries. The results showed that there is a significant effect of all dimensions of BPR in reducing costs in international business organizations operating in the Middle East. When studying the impact of the dimensions combined, the moral effect appeared at each processes (decentralization, re-engineering of human resources and industrial process technology), while the moral effect did not appear in (rebuilding organizational structures, improving total quality standards, and value engineering). This does not negate the importance of the impact of these dimensions, but rather shows a disparity between dimensions in reducing cost, when studying its combined effect. The study recommends that organizations should adopt modern management accounting methods, including value engineering, in order to identify and enhance activities that add value to the organization's operations, as well as identify and eliminate non-value adding activities, in order to reduce costs.

• 한국생산제조학회지
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• 제25권4호
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• pp.253-257
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• 2016

The effects of re-peening on the compressive residual stress and fatigue life of Al7075-T6 were investigated. The compressive residual stress induced on the surface of components by shot peening is known to increase the fatigue life. However, the fatigue load relaxes the compressive residual stress of components. Re-peening is a technique to again induce the relaxed compressive residual stress and increase the total fatigue life of components. In this study, the re-peening process was applied to fatigue-loaded specimens. The compressive residual stress and fatigue life were examined for re-peened specimens with fatigue ratios of 30%, 50%, and 70%. The results showed that the compressive residual stress of the specimens was relaxed under the fatigue load. The re-peening process significantly increases the compressive residual stress and total fatigue life.

• 한국기계가공학회지
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• 제18권11호
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• pp.109-114
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• 2019

Hydraulic pumps are widely used in fields such as machinery manufacturing, engineering and construction. Although the research on hydraulic engineering is mature, it is still necessary to examine various performance aspects in detail for specific applications. This paper will focus on the hydraulic pump used in special construction machinery that needs high temperature and high pressure resistance. It will analyze the theoretical design, structure and thermal characteristics of the pump system using the Fundamentals of Engineering (FE) method, and will measure the key tolerance parameters of the hydraulic pump to ensure the accuracy of the machining. Through this research, a good design method for the linear reciprocating type of hydraulic pump can be summarized.

• 한국융합학회논문지
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• 제11권10호
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• pp.1-7
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• 2020

뉴로모픽 소자 초기 단계인 저항 변화형 메모리 소자의 제작 공정으로, 진공 공정의 연속성을 유지하였고, 고집적, 고신뢰성을 보장하는 뉴로모픽 컴퓨팅을 위한 저항 변화 메모리 소자 제작 및 공정 기술에 적합한 플라즈마 모듈을 적용하였다. 플라즈마 모듈을 적용한 저항메모리(ReRAM) 소자의 제작과 연구는 ReRAM 소자 기반의 TiO₂/TiOx 산화물박막의 제작방법과 소재의 변화를 통한 다양한 실험을 통하여 완성되었다. XRD를 이용하여 rutile결정을 측정하였고, 반도체 파라미터 측정기로 저항 메모리의 HRS : LRS 비율이 2.99 × 10³ 이상이고, 구동 전압 측정이 0.3 V이하에서 구동이 가능한 저항 변화형 메모리 소자의 제작을 확인 하였다. 산소 플라즈마 모듈을 적용한 뉴로모픽 저항메모리 제작과 TiOx 박막을 증착하여 성능을 확인하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.2090-2092
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• 2003

Adaptive algorithms are widely used for various applications. One challenging application is an echo canceller in the long distance telephony network. This paper proposes the new variable step-size algorithm for adaptive lattice structure for echo cancellation. The new algorithm is using power of the output signal and the error signal to controlled the step of adaptation process. By this technique, the proposed algorithm is an excellent and effective in good stability. Performance comparison of the proposed algorithm and the other algorithm is made through simulation results.

• 한국인터넷방송통신학회논문지
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• 제21권2호
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• pp.79-88
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• 2021

과학용 소프트웨어는 전문가 수준의 깊이있는 도메인 지식 요구 등과 같이 고유한 특성들로 인하여 전통적인 응용소프트웨어와는 다른 개발 프로세스가 요구된다. 본 연구에서 우리는 과학용 소프트웨어 개발을 위하여 RE(Reverse Engineering)과 TDD(Test-Driven Development)에 기반한 V&V 개발 프로세스를 제안하였다. 또한 실제 프로젝트에 가상 시나리오를 구성하고 적용하여 절차를 검증하고 정교화 하였다. 과학용 소프트웨어 개발을 목적으로 제안된 본 연구의 개발 프로세스는 고품질, 고 신뢰성을 제공할 수 있는 소프트웨어 개발 및 적용에 기여할 것이다. 또한 본 연구는 과학용 소프트웨어 개발 및 연구의 저변 확산의 계기가 될 것으로 기대된다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.613-613
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• 2006

• 한국기계가공학회지
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• 제14권2호
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• pp.19-24
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• 2015

Gears are produced through a variety of methods. In general, a metal piece is formed into the general shape of a gear through rough cuts. The gear then moves on to a more precise machine that removes more material. Grinders work via abrasion, rubbing a rough surface against a work piece at such high speeds that it literally scrapes unwanted material away from the item. Since the grinder is spinning so fast, the material is removed very quickly. This allows a grinder to remove a very small amount without taking any unwanted material with it. This study investigates the effect of grinding process parameters like grinding spindle speed and table transfer speed on the gear grade and grinding efficiency.

• 한국기계가공학회지
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• 제19권4호
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• pp.79-84
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• 2020

Induction bending via high-frequency heating is widely used for manufacturing pipe and section steel bends. It allows productivity improvement, unit cost reduction, delivery time compliance, and good mechanical properties. The recent increase in high-end vessels and offshore plants has raised the demand for high-frequency bending, which should improve the product quality and reduce the costs by simplifying the fabrication process; therefore, the characteristics and performance of this technique must be studied and proper design technology is required. During hot pipe bending via induction heating, the outward wall thickness of the pipe is thinned due to tensile stress and this thickness reduction cannot exceed 12.5%. This study focused on pipe bends with a bending curvature of 5D and their optimization design; in particular, the conditions that can both improve the productivity of the high-frequency bending process and keep the maximum thickness reduction below 12.5% were determined.