• Korean Chemical Engineering Research
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• 제59권3호
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• pp.393-398
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• 2021

리튬이온전지의 성능을 최적화하기 위해서는 여러 열화 요소들을 고려한 성능 예측 모델링 기술이 필요하다. 본 연구에서는 리튬이온전지의 사이클 노화로 인한 방전 거동 및 사이클 수명 변화를 수학적으로 모델링하였다. 모델링의 신뢰성을 검증하기 위해 0.25C로 사이클 시험을 진행했으며, 30 사이클 간격으로 진행한 RPT (Reference performance test)를 통해 전기적 거동을 파악하였다. 기존의 리튬이온전지의 사이클 수명 예측 모델에 BOL (Beginning of life)에서 일어나는 현상 중 하나인 Break-in 메커니즘을 반영하여 수명예측 정확도를 개선시켰다. 모델에 근거하여 예측된 사이클 수명 변화는 실제 시험 결과와 잘 일치하였다.

• 상하수도학회지
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• 제12권3호
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• pp.65-74
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• 1998

Life cycle assessment (LCA) on two different sludge treatment systems, on-site treatment and pipe-collected intensive treatment was performed to estimate the environmental impact in the aspect of global warming effect. As a main parameter of the estimation, $CO_2$ was chosen and quantified through the whole life cycle of the treatment systems including construction, operation and dismantlement. In this study, the changes of $CO_2$ production unit (CPU) by up-scaling n currently used sludge treatment processes were also calculated. As the result, a larger amount of $CO_2$ was exhausted from the construction step of intensive treatment system than that of on-site treatment system, because an additional pipe-collection system was needed in intensive treatment system. However, the total amount of $CO_2$ exhausted from whole life cycle including not only construction and dismantlement but also 15 year-operation and maintenance was reduced by appling intensive treatment.

• 동력기계공학회지
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• 제21권1호
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• pp.43-49
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• 2017

This work aims to investigate on the low cycle fatigue life assessment, which is adopted on the strain-life relationship, or better known as the Coffin-Manson relationship, and also the strain energy density-based model. The low cycle fatigue test results of Alloy 617 weldments under $900^{\circ}C$ have been statistically estimated through the Coffin-Manson relationship according to the provided strain profile. In addition, the strain energy density-based model is proposed to represent the energy dissipated per cycle as fatigue damage parameter. Based on the results, Alloy 617 weldments followed the Coffin-Manson relationship and strain energy density-based model well, and they were compatible with the experimental data. The predicted lives based on these two proposed models were examined with the experimental data to select a proper life prediction parameter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.2169-2170
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• 2011

This paper presents about the analysis on cost factor reduction using the life cycle cost model for motor block in the KTX-1. Until now, most life cycle cost of the system as a whole that has been studied. but in case of railway industry part, LCC studies are needed on the subsystem like a propulsion control system because subsystems are developed continuously localization. Therefore, In this paper presents cost breakdown structure for life cycle cost (LCC) estimation for localization development of propulsion control system (Motor Block) in high speed railway vehicle (KTX-1). Also to analysis LCC on motor block, it was analyzed physical breakdown structure (PBS) and preventive cost on propulsion control system in view of maintenance cost. Based on this, we describe life cycle cost on motor block of KTX-1.

• 한국안전학회지
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• 제17권2호
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• pp.63-68
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• 2002

Life Cycle Cost analysis technique is introduced to evaluate cost-effectiveness of two paint systems of steel bridges. The systems are a conventional paint system and a galvanized paint system. The all costs during safe lift such as initial cost repainting costs, disposal costs are considered for the lift cycle cost analysis. The NIST model is used and BridgeLCC 1.0 developed by the NST is utilized as the lift cycle cost analysis tool. It is concluded that, in spite of expensive initial cost, the durable paint system may be cost-effective compared with conventional paint system.

• Steel and Composite Structures
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• 제27권5호
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• pp.633-646
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• 2018

This study investigated the seismic performance of a hybrid damper composed of a steel slit plate and friction pads, and an optimum retrofit scheme was developed based on life cycle cost. A sample hybrid damper was tested under cyclic loading to confirm its validity as a damping device and to construct its nonlinear analysis model. The effectiveness of the optimum damper distribution schemes was investigated by comparing the seismic fragility and the life cycle costs of the model structure before and after the retrofit. The test results showed that the damper behaved stably throughout the loading history. Numerical analysis results showed that the slit-friction hybrid dampers optimally distributed based on life cycle cost proved to be effective in minimizing the failure probability and the repair cost after earthquakes.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2006년도 춘계공동학술대회 논문집
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• pp.1832-1839
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• 2006

제품의 개념설계 단계는 제품의 주요특성과 라이프 사이클 전반에서 발생하는 Life Cycle Cost(LCC)의 대부분을 결정하는 중요한 단계이다. 이에 따라 개념설계 단계에서의 Life Cycle Cost Analysis(LCCA)의 필요성이 강조되고 있다. 그러나 LCCA는 제품의 경제성과 사용성, 친환경성 사이에서의 합리적인 의사결정을 지원하기에 한계가 있다. 본 논문은 개념설계 단계에서의 새로운 의사결정지원도구로서 기업 관점의 제품 라이프사이클 기업 가치(LCCV)분석 프레임워크를 제안하고, 그 핵심모듈인 기업 비용 예측모델 (LCCCEM)을 소개한다. 이 프레임워크를 통해 기업이 제품의 경제성과 시장성, 친환경성 사이에서 보다 전략적이고 합리적인 의사결정을 수행하도록 지원할 수 있을 것으로 기대한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.115-120
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• 1997

Environmental Product Life Cycle Management is an activity for defining and describing the product, process or activity environmentally. Especially, the main responsibility for the environmental impact of products lies in the design phase of product. Designers cany a heavy responsibility to determine technical, economic and ecological properties of the product. So in order to help designers, structured understanding and application of treating large amount of data and infonnation should be considered. This paper presents a methodological approach for decision supporting to build Product Life Cycle Management system and show a set of database modeling. Additionally, a key issue for databases is the quality of the provided information.

• 한국태양에너지학회 논문집
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• 제24권4호
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• pp.55-63
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• 2004

The purpose of this study is to development of life cycle cost analysis methodology of HVAC system for decision maker. The results of this study are as follows; maintenance/management, equipment construction, planning/design, and demolition/sell phases (1) To develop the cost breakdown structure for LCC in HVAC system, this study apply the method of additional pertinent level, title, CBS number, block number and variable index. (2) LCC analysis order of HVAC system compose four phase. (3) Life cycle costing influence diagram can bring us to make the most efficient decision through a visual graphical diagram that is shown relationship among variables and that decision maker traces easily from life cycle cost analysis situation.

• International Journal of Human Ecology
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• 제1권1호
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• pp.79-93
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• 2000

Using the 1995 Survey of Consumer Finances, this study investigates how family life-cycle stages and financial management practices affect household saving. First findings are that household income and householders education, race and ethnicity have significant effects on saving. Second, regarding the effect of the family life-cycle stages, younger married couples without children, middle pre-retired households without dependent children, and older households without dependent children are more likely to save than other similar households in the life-cycle stage of younger single households. Third, households with longer financial planning horizons, saving goals for retirement, purchase of durable goods and emergency goods, and low credit card debt are more likely to save. Based on the results, implications for financial management education and public policy are suggested.