• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2006.11a
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• pp.123-130
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• 2006

Recently, Korean government promotes BTL(Build-Transfer-Lease) for their public construction project to apply private sector's experience and finance initiatives. Many of public buildings and civil infrastructure projects were planned to be delivered by BTL and it helps to continue public projects under tight budget conditions. Since the characteristics of BTL projects, creative ideas for the project function, performance and its LCC (Life Cycle Cost) become more important than usual public work project. This paper introduces the systematic "VE job Plan" application techniques for BTL project and shows the process. This study shows the application of "VE job Plan" for BTL project to help decision making and value improvement. Also, Project cost was estimated by LCC (Life Cycle Cost) analysis. Technical "FAST diagram"was developed and used to find major functions of the project. So, it helps to improve performance of functions and make creative ideas. FAST diagram also help to find relationships between functions and cost. A case study (Daegu Art Gallery BTL Project) was conducted using proposed "VE job Plan. Study demonstrates how value management helps save money and increase functional performance. Researcher found that project can save cost and improve performance of functions significantly by using appropriate VE analysis process at appropriate time.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.72-77
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• 2002

The development of a Pay Adjustment (PA) procedure for implementing Performance-related Specifications (PRS) is known to be a difficult task faced by most State Highway Agencies (SHAs) due to the difficulty in such areas as selecting pay factor items, modeling the relationship between stochastic variability of pay factor items and pavement performance, and determining an overall lot pay adjustment. This led to the need for an effective way of developing a scientific pay adjustment procedure by incorporating Life Cycle Cost Analysis (LCCA) embedded Monte Carlo approach. In this work, we propose a prototype system to determine a PA specifically using the data in the pavement management information systems at Wisconsin Department of Transportation (WisDOT) as an exemplary to other SHAs. It is believed that the PRS methodology demonstrated in this study can be used in real projects by incorporating the more accurate and reliable performance prediction models and LCC model.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.11
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• pp.2191-2198
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• 2017

The PME(precision measurement equipment) used in the measurement to check the performance of the equipment in military weapon system is periodically calibrated to maintain measurement reliability during the life cycle. Previous studies suggest that reliability models are determined by considering sample size and characteristics of equipment. However, it may not be fit well to apply a single model assuming the same characteristic distribution for the maintenance date of many kinds of PMEs. This paper proposes that the most suitable calibration interval for maintenance data is selected through the F-test and the performance index evaluation among the calibration intervals estimated from the measurement reliability models assuming the characteristic of the bath-tub curve during the life cycle of various PMEs. The research results show that the reliabilities of various types of equipment are maintained during calibration intervals.

• Journal of the Korean Solar Energy Society
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• v.30 no.6
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• pp.81-88
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• 2010

This study compared the feasibility of utilizing a wood bioenergy system over a conventional central heating and cooling system and a cogeneration system in an apartment complex. The performance of the three systems were compared in the following areas: energy consumption, environmental impact(output of CO2, CH4, and N2O), and life cycle cost. The results showed that energy performance of the wood bioenergy system was similar to the conventional central system (just a 1% improvement) but the cogeneration system showed a 12% reduction in energy consumption compared to the conventional system. In terms of environmental impact, the bioenergy system reduced pollutants by 50% while the cogeneration system reduced pollutants by 30% compared to the conventional system. Life cycle cost analysis indicated bioenergy and cogeneration to have an 8% and 19% improvement over the conventional system. The findings of the study suggest that it is both economically and environmentally beneficial to use a wood bioenergy system in place of a conventional central heating and cooling system in apartment complexes.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.2
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• pp.77-88
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• 2009

According to the size of NAND flash memory as the storage system of mobile device becomes large, the performance of address translation and life cycle management in FTL (Flash Translation Layer) to interact with file system becomes very important. In this paper, we propose the continuity counters, which represent the number of continuous physical blocks whose logical addresses are consecutive, to reduce the number of address translation. Furthermore we propose the prefetching method which preloads frequently accessed pages into main memory to enhance I/O performance of flash memory. Besides, we use the 2-bit write prediction and asynchronous writing method to predict addresses repeatedly referenced from host and prevent from writing overhead. The experiments show that the proposed method improves the I/O performance and extends the life cycle of flash memory. As a result, proposed CFTL (Clustered Flash Translation Layer)'s performance of address translation is faster 20% than conventional FTLs. Furthermore, CFTL is reduced about 50% writing time than that of conventional FTLs.

• Journal of the Korea Institute of Building Construction
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• v.9 no.2
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• pp.63-68
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• 2009

Construction Performance measurement and management has been interested by construction practitioners. However, current construction project management practices are related to short-term improvement plans rather than long-term and systematic approaches based upon performance analysis. AR a result, there is a need for developing of a collaborative plan over project life cycle. Therefore, this paper reviews extensive literature and proposes the construction performance estimating model using a system dynamics. The paper proposes casual maps for planning, design, procurement, and construction phases. Each casual map includes all performance indicators and factors that impact on performance directly or indirectly. These casual maps that were developed by system thinking will enhance the understanding of the relationships among performances and factors. After further data gathering, these models can be used to estimate construction performance and eventually these will save project costs and shorten project schedule.

• Journal of the Korean institute of surface engineering
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• v.49 no.5
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• pp.408-415
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• 2016

The offshore structures exposed to harsh corrosive such as the marine environment is essential for the quality management technique throughout the life cycle of initial design, construction and operation. Also, it should satisfy the design life and ensure the safety of the substructure with optimization of design process. This study focused on optimization of design condition for corrosion protection of wind turbine structure and computational analyzing was performed to evaluate the performance of corrosion protection with utilizing practical experimental data. We expect this analytical study contribute to improve the corrosion maintenance stability and economical efficiency of designing wind turbine structures. As a result, the design of cathodic protection system using sacrificial anodes required accurate identification of current density in order to meet the long term design life, which can be seen that a change of structure surface's coating breakdown factor is one of the key influencing factors.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.46 no.1
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• pp.48-54
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• 2023

Guided missiles are a one-shot system that finishes their purpose after being used once, and due to the long-term storage until launch, the storage reliability is calculated during development, and performance is maintained through periodic inspections until the life cycle arrives. However, the reliability standards applied in the development of guided missiles were established by analyzing data accumulated by the United States during long-term operation in the country, and since they are different from our environment, the 00 guided missiles that have been deployed in the armed forces for more than 10 years under the premise that there is a difference from actual reliability. As a result of verifying the appropriateness of the current inspection cycle by analyzing the actual reliability of the missile, the necessity of changing the inspection period was derived because it was higher than the predicted reliability. It is proposed to build and utilize a lifespan management system that can systematically collect all data such as shooting and maintenance results by classification, and to establish a reliable reliability standard based on the accumulated data.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.52-60
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• 2017

This paper forces on the analysis of the overall outcome regarding Performance Based Logistics(PBL) application for Air Weapon System. We used data from domestically developed aircraft such as KT/A-1 and T-50 as well as data from foreign F-15K aircraft and F100 Engine to analyze the current ROKAF PBL application results. Furthermore, this paper thus suggests various techniques to maximize the outcome of user-based PBL performance such as clarifying the responsibility between customer and the company, developing standardized PBL performance index under TLCSM, PBL related maintenance capacity development, wartime PBL implementation process of domestic/foreign companies and many other schemes based on the analyzed data.

• Transactions of the Korean hydrogen and new energy society
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• v.13 no.1
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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.