• 한국수소및신에너지학회논문집
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• 제13권1호
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• pp.3-12
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• 2002

In this study, it achieved life cycle assessment to estimate environmental performance for naphtha steam reforming that account for the production over 50% of total hydrogen output. Although hydrogen dosen't emit air emissions, especially, $CO_2$, a large of $CO_2$ is emitted in hydrogen production process. In the result of this study, it ascertained the truth that $CO_2$ is emitted at the rate of $6.3kg/kgH_2$ and that result from steam reforming reaction and use of fossil fuel in hydrogen manufacturing process. Above all, 57% of total $CO_2$ emissions is emitted in process of steam reforming of naphtha and so it knew that the principle of steam reforming is key issue in aspect to environment. Also, it compared hydrogen by fuel of fuel cell vehicle with gasoline fuel of general gasoline vehicle to analyze relative environment of hydrogen for fossil fuel during the life cycle. As the result, it might be difficult in improvement of environment because $CO_2$ emissions during the hydrogen manufacturing process is nearly the same with that during the use of gasoline.

• 한국건축시공학회지
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• 제9권6호
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• pp.151-159
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• 2009

최근 LNG 수요 증가로 인한 해외 LNG 플랜트 프로젝트의 지속적인 발주 증가로 국내 건설업체의 해외 진출이 크게 증가하고 있다. 또한 시공 및 사업관리 기술의 발전으로 예전에 비해 고부가가치를 창출할 수 있는 기회가 많아지고 있다. 그러나 일부 선도기업을 제외한 대부분의 중견 건설업체는 고급 인력과 실무 경험의 부족으로 인한 어려움을 겪고 있는 실정이다. 선진기업의 경우 체계화된 업무 프로세스 구축을 통해 이러한 어려움을 해결하였다. 이에 본 연구에서는 플랜트 사업의 생애주기 업무 프로세스 중 시공 전 단계를 대상으로 업무를 규명하고 지식관리 항목을 포함한 상세 프로세스를 분석하였다. 이는 전체 생애주기 업무 프로세스를 분석하고 표준화하는 연구의 사전 단계로 향후 지식관리 시스템을 개발하여 통합관리를 하는데 활용 할 수 있을 것으로 기대한다.

• 한국기계가공학회지
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• 제14권2호
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• pp.75-80
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• 2015

The rebar factory production process involves the repetitive bending of rebars. Therefore, the fatigue failure of the rebar bending machine needs to be considered. In this paper, fatigue analysis of the rebar machine was performed using the commercial software DAFUL, which is based on MFBD (Multi Flexible Body Dynamics). The rotating roller, fixing roller and rebar were modeled by the finite element method. The rebar bending process is simulated and the mechanical stresses on the rollers are calculated. Structural analysis of the rebar bending roller was performed using the maximum bending angle of $180^{\circ}$ and maximum processing rebar diameter of ${\Phi}19mm$. Then, for fatigue analysis, the S-N curve of STD-11 was. The fatigue life of rollers is estimated by modified Goodman diagram. The fatigue life range of the rotating roller is $2.99961{\times}10^5{\sim}1{\times}10^8$ while that of the fixed roller is $2.53142{\times}10^5{\sim}1{\times}10^8$. STD-11 has an infinite life cycle after $1{\times}10^8$. Therefore, the rollers of the rebar bending machine may be expected to suffer fatigue failure. Thus, we performed a parameter study of fatigue life according to various axial radii of the fixed roller and rotating roller, and redesign of the rebar bending machine. Consequently, the axial radius of the fixed roller and rotating roller was found to be 35~37.5mm and 30~35mm, respectively, and an infinite life cycle was confirmed at these.

• 치과방사선
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• 제13권1호
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• pp.29-73
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• 1983

The age related changes in the life cycle of the progenitor cell population of murine oral epithelia was studied. Using radioautographic methods which have been adopted in previous cell cycle studies, the age-related changes of different phases in renewing cells of the palatal, buccal and lingual mucosae were determined. The results confirm published findings on cell cycle changes of epithelia with aging and illustrated further that mitotic phase which has hither to been considered stationary, also changes with aging. The major parts revealed by this study are as follows: 1) The basal progenitor cells in different regions of oral mucosa have different generation times. 2) The basal cell cycle time increases as a function of aging and the region most affected by aging appears to be the epithelium of the cheek. 3) The phases of the cell cycle affected by the process of aging are in increasing order of magnitude: M-, S- and G₁-phase. 4) The age elated change in the number of DNA synthesizing basal progenitor cells occurs at two age periods. Between 1 and 12 months of life it decreases, while from 12 to 20 months it increases.

• 한국전자통신학회논문지
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• 제8권8호
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• pp.1161-1170
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• 2013

2013년 현재 개인정보보호를 위한 사회적 합의결과로 도출되어진 관련법이 제정되고 수차례의 개정을 통해 IT분야를 비롯한 다양한 사회적 업무분야에 최종적인 정보보호를 위한 명확한 성문법적인 정책과 지침 등의 방향이 제시되어 졌다. 이러한 일련의 개인정보 중요성에 대한 사회적 이슈를 기반으로 새로운 개인정보 접근 패러다임이 나타났고 정보보호라는 거시적인 접근 방법에서 전문적인 접근방법의 필요성이 대두되어졌다. 물론 현재까지 모든 개인정보 형태의 자료들을 특정한 정보의 범주에 모두 제한하고 경계를 두는 것은 다소 무리수 있어 보이나 IT분야를 기반으로 하는 정보의 홍수 속에서 개인정보의 흐름을 확인하고 보안대상으로 선정하는 부분은 표준화되어 진 것은 사실이다. 다만 아직까지도 개인정보 Life-Cycle의 5가지 표준화된 흐름인 수집, 처리, 제공, 보관, 파기 등을 모든 기업과 기관이 보유한 정보들에 일상적으로 적용하기 어려운 경우도 발생하고 있다. 따라서 이원화된 계층적 개인정보 Life-Cycle 접근제어 방법론을 제안함으로써 표준화 방법론을 제안한다. 본 연구결과는 개인정보 Life-Cycle에 최적의 접근제어 가능한 현실적인 자료를 제공하고자 한다.

• 한국산학기술학회논문지
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• 제13권7호
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• pp.3194-3200
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• 2012

본 연구의 목적은 금융IT 발전과정의 역사적 사실들을 체계적으로 정리하고 다양한 추적 과정을 통해 입증된 교훈을 통해 조만간 가시화될 2020년대를 준비하는 신 차세대 시스템에서의 코어뱅킹 모델의 새로운 발전 모형과 방향성을 제시하는데 있다. 이를 위해 금융IT 발전과정 40년 동안 중요한 영향을 미쳤던 의미있는 패턴들을 도출 및 분석하고 코어뱅킹 모델의 라이프사이클을 역 추적하여 코어뱅킹 모델의 새로운 모형을 제시하였으며, 이를 활용하게 될 신 차세대 시스템의 발전방향도 함께 제시하였다. 연구결과 우리나라 금융IT 시스템과 코어뱅킹 모델의 라이프사이클은 각각 약 10년으로 분석되었으며, 최장기 모델의 라이프사이클은 33년으로 추정되었다. 향후 코어뱅킹 모델의 발전 모형은 기존 모델의 기본 구조에 비즈니스 허브 기능과 상품수명 주기관리 기능을 추가시키는 것이 바람직한 것으로 나타났다. 또한 신 차세대 시스템의 개발방식으로 빅뱅 방식은 지양해야 하며 IT기술 측면보다는 업무지향 측면에서 추진되어야 한다. 아울러 금융IT 분야는 융합산업 분야로 성장시켜 나가야 하며, 이를위해 코어뱅킹 모델연구의 체계화와 전문인력 양성이 필요하다. 본 연구는 우리나라 금융IT 발전과정을 처음으로 체계적으로 정리하였다는 점과 최초로 코어뱅킹 모델의 집중 분석을 통해 새로운 모형을 제시함으로써 향후 전개될 신 차세대 시스템 발전 방향의 가이드 라인을 제시하였다는데 의의가 있다.

• Journal of Information Technology Applications and Management
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• 제20권2호
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• pp.69-87
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• 2013

The expanded spiral model in this paper consists of five processes of architecture design, architectural construction, architectural maintenance, operation, and architectural management. The former four processes are executed alternatively, while the latter architectural management process is executed continuously interacting with the other processes during the whole life cycle of the system. The expanded spiral model provides a conceptual framework to sort discussions of architectural degeneration into those of product-oriented processes and those of management processes, making it possible to incorporate the models and body of knowledge about project and program management especially those of Project Management Institute, into discussions of architectural degeneration. A good architecture decomposes the software-intensive system into components mutually interacting in a well-formed structure. The architecture design process and the architectural construction process together create the object system with well-designed architecture. The architectural maintenance process prevents the implemented architecture deviate from the designed architecture. The architectural management process monitors the changes of requirements including architecturally significant requirements, supports the other processes to be executed reflecting various perspectives of stake-holders, and creates and documents the reasons of architectural decisions, which is considered as a key element of the architecture.

• 정보처리학회논문지D
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• 제9D권1호
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• pp.81-90
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• 2002

More than 50% of defects and errors in the software development projects are related to the requirements[14]. But the development methodologies can not provide enough supports to the requirements management and changes. In the real world, the requirements keep changing as the requirements at the early development phase are usually incomplete, the developer′s understanding of the problem will be constantly changed during the software process, and new requirements may emerge with the organizational and environmental changes. In this paper, a requirements management process that can be integrated into the development methodologies is proposed to extend the requirements management over the whole development life-cycle and to support the requirements changes at the design/implementation/test phases. To evaluate the proposed process, it was compared to the existing requirements managements processes and models, and examined through a integration test with a widely used development methodology "MaRMI" to show the expected improvements at each development phase.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.1106-1113
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• 2022

Cost segregation helps reduce tax liabilities by reclassifying real property to personal property and accelerates tax depreciation of a property. A typical cost segregation study requires much time and high costs. This study proposed a BIM integrated cost segregation process that can be applied to any commercial building project. The proposed BIM-based cost segregation process was verified in a new commercial construction project. It approved that this approach can: (1) increase the cash flow for the owner and provide assistance to tax-paying enterprises; (2) enable the contractor to use it as an added value in the bidding process; (3) realize data sharing in a common platform to improve the cost segregation study efficiency and reduce costs and errors; (4) contribute to the asset management in the life cycle of buildings while filling in the blank of cost segregation process. Future studies will focus on the automation of cost segregation and asset management in building construction's life cycle.

• Nuclear Engineering and Technology
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• 제55권10호
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• pp.3571-3580
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• 2023

The application of the induction bending process to pipe systems in various industrial fields is increasing. Recently, efforts have also been made to apply this bending process to nuclear power plants because it can innovatively reduce welded parts of the curved pipes, such as elbows. However, there have been no cases of the application of induction bending to the piping of nuclear power plants. In this study, the applicability of the P91 induction bending piping for the sodium-cooled fast reactor PGSFR was validated through high temperature low cycle fatigue tests and creep tests using P91 induction bending pipe specimens. The tests confirmed that the materials sufficiently satisfied the fatigue life and the creep rupture life requirements for P91 steel at 550 ℃ in the ASME B&PV Code, Sec. III, Div. 5. The results show that the effects of heating and bending by the induction bending process on the material properties were not significant and the induction bending process could be applicable to piping system of PGSFR well.