• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.143-146
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• 1998

The $LiCoO_2$ powder was synthesized at >$700^{\circ}C$, >$850^{\circ}C$ by solution route. In this paper, we investigated X-ray diffraction, and charge-discharge performance for $LiCoO_2$/Li and $LiCoO_2$/MPCF cell. The $LiCoO_2$/Li ceSl exhibited a high avmge discharge potential of 38-3% and a good cycle life performance at 5(hnA/g during chargedischarge cycling between 43-3.0V. And, the $LiCoO_2$MPCF cell showed a high average discharge voltage of 3.6-3.W and a excellent cycle life prfomam during chargedischarge cycling b&wm 4 2-2.W. As a result, the $LiCoO_2$ powdm syd-eizd by solution route is a good cathode material for lithium ion secondary battery.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.11
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• pp.621-628
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• 2009

The objectives of this study are to analyze the performance of a river water-source heat pump and to carry out economic assessment for the heat pump. The COP of the river water-source heat pump was 3-21% higher than that of the air-source heat pump because river water provides stable operating temperature compared with air temperature throughout the year. The economic analysis was carried out by comparing the initial and operating cost of the river water-source heat pump with those of the conventional air-source heat pump. The ratio of the life cycle operating cost to the life cycle cost increased with the increase of building capacity. The payback period was found to be less than 3.5 years when the capacity of the river water-source heat pump was larger than 10 RT.

• Clean Technology
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• v.1 no.1
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• pp.34-46
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• 1995

Clean Technology goes beyond Clean-UP (or "End of PiPe) Technologies to include Pollution prevention, waste minimisation, and cleaner production. However, the concept of Clean Technology goes deeper than changes in technology, to ways in which human needs can be satisfied sustainably. In other words, Clean Technology, concentrates on delivering a human benefit rather than making a product. Introducing cleaner technology may therefore involve new commercial relationships as well as new technological practices. In some economic sectors, this involves leasing or providing a service rather than selling a product. Life Cycle Assessment (LCA) is an important tool in Clean Technology. LCA involves determining all the resources used and all the wastes and emissions produced in providing the human benefit. Use of LCA ensures that improved environmental performance in one part of the Life Cycle is not achieved merely at the expense of more environmental damage elsewhere. Going beyond LCA, the concepts of Life Cycle Design and "metabolised" use of materials are approaches to obtain maximum benefit from materials as they pass through the human economy. "Closed-loop" use can be a component of clean technology. Looking beyond simple re-use and recycling, a material may pass through a "cascade of uses". typically a series of applications with progressively lower performance specifications. Closed-loop use necessarily involves a change in commercial practice, because the material or product must be recovered after use.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.557-564
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• 2006

Life-cycle performance and maintaining cost predictions are required for the effective management for bridges. In Korea, the importance of management of bridges has been recognized over the past two decades, resulting in the development of databases and various bridge management support tools by both government and private sectors. However, none of these tools has truly included the expected features of the bridge management system (EMS) for the next generation such as the quantification of the effects of maintenance interventions on bridge condition and safety. In this paper, a novel quantification process to simulate the life-cycle performance of steel box bridges has been developed. The process is based on the Response Surface method. Various performance-related variables aloe investigated to identify a set of significant design variables to construct the response surfaces.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.1
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• pp.54-61
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• 2004

The purpose of this study is to improve of energy performance in school buildings. Many building renovations have mainly focused on commercial buildings and houses, but school buildings have no attention in this field although there are many buildings that show degraded energy performance and there are many old fashioned buildings which need renovation. This study was carried out through the survey, field study, energy simulation and life cycle cost analysis. The results of this study can be summarized as follows: In model building, large amount of heat were lost at the building envelope, such as non-insulated skins, window-sills and window-frame joints. According to the simulation result, about 15％ of heating energy is saved by the insulating works compared to pre-renovation condition. Also, LCC analysis revealed to be more effective to select a exteria wall insulation such as a dryvit system.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.355-359
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• 2009

Recently, the railway has been growing as the eco-friendly transport which is excellent for reducing carbon dioxide. However, the level of using tools to quantitatively and objectively evaluate the environmental performance is still low in the rail industry. Therefore, it is necessary to introduce Environmental Product Declaration(EPD) which describes the environmental performance by using Life Cycle Assessment(LCA) for evaluating the environmental impacts through entire life cycle of a product. The EPD enables stakeholders including policy makers, operation body, vehicle manufacturers and drivers and consumers to be informed about the superior environmental performance of rail vehicles.

• Composites Research
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• v.19 no.1
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• pp.43-48
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• 2006

High performance fiber reinforced cement composites have better performances than traditional cement based materials, therefore, have been expected as new construction applications such as the materials for construction & bridge structure, repair and rehabilitation applications, anti-collapse applications, anti-noise applications etc. However, they have lots of the problems such as material design, fabrication method and structural analysis. Also, the most serious problems of High performance fiber reinforced cement composites have been expensive initial cost, lack of long-term exposure data. As a result, it is needed that the efforts for lowering the initial cost and accumulation of long-term exposure. There has been hardly assessment results of life cycle cost for HPFRCC in construction field, but some papers showed that total life cycle cost could be profitable if the initial cost could be reduced.

• Journal of Korea Water Resources Association
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• v.36 no.5
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• pp.715-724
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• 2003

It is true that SOC facilities, such as dams, need long life cycles since more time has to be invested for the phases of planning, examination, feasibility study, design, contract, construction, and maintenance. This longer life cycle is easily exposed to the risk. And thus, brings additional cost by the delayed project, convenient loss according to the additional run of use, and benefit lose of not to using the facilities. So, the purpose of this study is to try to find a solution to reduce these time consuming problems which could diminish the whole national competition. Hence, this study is to show efficient, systematical project performance and network model by using reciprocal analyses between the construction period and cost based on economical analysis of each phase of life cycles. In addition, on the basis of these outputs, the Fast Track Method is suggested as an alternative solution as a new Approach in Life Cycle's Analysis.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.7
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• pp.593-598
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• 2016

Static tests and low-cycle fatigue tests were conducted to analyze the characteristics of the bellows for LNG vessels according to the forming methods. The cycle life of bellows was tested based on the specified cyclic life, 80000 cycles, to analyze the difference in characteristics between pre-and post-test data by measuring the strain and stress of each convolution of formed bellows. The low-cycle fatigue test was conducted using a strain gauge that was attached to the convolution of bellows. Formed bellows were placed on the structural test device which was equipped with a hydraulic system and was capable of moving in the x-y direction. Data was measured and processed by a multi recorder. Through the static test and low-cycle fatigue tests results, the difference between the cycle life of bellows formed by mechanical methods and of those formed by hydraulic methods was investigated. Moreover, the cause of difference in cyclic life according to forming methods was performed.

• Journal of Information Technology Applications and Management
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• v.20 no.4
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• pp.127-149
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• 2013

Competitiveness of service industry in Korea is relatively lower than OECD countries'. Korean government, therefore, has been trying to improve the competitiveness of service industry by accelerating information technology (IT) adoption. Even though most of factors of IT can be contributed to improve the financial performance, it may be affected differently among various industry types and life cycles of companies. Therefore, it is one of very important research issues to analyze the influential effect of IT considering industry types and organizational life cycles in service industries. The purpose of this study is to find out critical success factors of IT which influence financial performance considering different types and life cycles of service industries. We developed the model and identified key success factors of IT adoption as IT system quality, Information quality, IT maintenance, CEO support, IT education of organization, and IT competence of user. Additional analysis of moderating effect by organizational life-cycle and types of service industry are conducted. For data sampling 856 companies are participated and total 2,000 questionnaires are collected. Structural equation modeling method is conducted for statistical analysis. The results show that the model is valid and most of success factors of it are very useful for improving financial performance of service industries except organizational IT education. Moderating effect of industry types and organizational life cycles is valid but partially accepted. The results might be able to provide useful directions and guide lines of IT acceleration in service industries.