• Proceedings of KOSOMES biannual meeting
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• 2006.05a
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• pp.201-206
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• 2006

As the seriousness of the global environment is gaining increasing our attention recently, studies on application of LCA(Life Cycle Assesment) to ship are being carried dynamically in various industry fields. This study examined general outline about local and international application cf LCA to ship. First of all, international background for the appearance of LCA and its general meaning are introduced. The state-of-the-art for its application to ship will be also explained. Finally, domestic study methodology for application of LCA to ship were suggested.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.4
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• pp.557-566
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• 2002

This paper presents an optimum deck and girder system design for minimizing the life-cycle cost(LCC) of steel box girder bridges. The problem of optimum LCC design of steel box girder bridges is formulated as that of minimization of the expected total LCC that consists of initial cost, maintenance cost and expected retrofit costs for strength, deflection and crack. To demonstrate the cost effectiveness of LCC design of steel box girder bridges, the LCC optimum design is compared with conventional design method for steel box girder bridges. From the numerical investigations, it may be positively stated that the optimum design of steel box girder bridges based on LCC will lead to mote rational, economical and safer design.

• Journal of the military operations research society of Korea
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• v.30 no.1
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• pp.168-188
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• 2004

Integrated Logistic Support (ILS) is a management and technical process whereby all the diverse elements needed to fully operate, maintain, and totally support a materiel system in the field are identified, developed, and deployed simultaneously and on an equal priority with the item of materiel being supported. The test and evaluation (T＆E)of ILS act the important role of reduction of life-cycle cost and keeping of good performance for weapon system. In this article, we suggest the alternatives for improvement in the test and evaluation of ILS during weapon system acquisition. It is hoped that this research is valuable and beneficial to persons related weapon system acquisition, in order to maximize the efficiency of defense acquisition management by reducing the life-cycle cost and enhancing the quality of weapon system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.11
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• pp.1615-1621
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• 2014

A wireless tram which runs without catenary and instead uses batteries installed in the tram has been recently researched actively. This paper presents a new method maximizing absorption of regenerative energy of a wireless tram and extending life cycle of the energy storage device in the wireless tram by applying line-optimized charging and discharging scenario. Energy efficiency and life cycle of energy storage system (ESS) are highly dependent on the characteristic of operating conditions. For example, frequent charge and discharge with high power cause the problems that decrease the battery life cycles. Hybrid energy storage system (HESS) is combination of two ESSs which have complementary characteristics to each other. HESS can provide even better functionality and performance than the battery only ESS due to the synergy effect of two ESSs. This paper also provides a power distribution strategy and driving scenarios which increase the life cycle and energy efficiency of the HESS consisting of a battery and an ultra-capacitor. The developed strategy was tested and verified by a hardware-in-the-loop-simulation (HILS) system which emulates the a wireless tram.

• 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.

• The Journal of Society for e-Business Studies
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• v.24 no.2
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• pp.199-216
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• 2019

The public SW market is 3 trillion won, which is less than 10% of the total SW market. However, due to the nature of the domestic market, it is an important market with a relatively large impact on small and medium-sized software companies. In this market, government is operating the Public SW Project Demand Forecasting System in order to support the marketing activities of small and medium sized SW companies and establish a fair market order. The current system has limitations such as lack of user convenience, insufficient analysis capability and less business connection. This study was conducted to identify the problems of these systems and to propose a new system for improving the convenience of users and expanding the information utilization of SMEs. To this end, we analyzed the requirements of each stakeholder. We proposed the 2-phased forecasting cycle, the management cycle, and the system life cycle of public SW projects and created a unified identifier (UID) so that the information of those projects can be identified and linked among them. As a result, an integrated reference model of project information management based on system life cycle was developed, which can explain the demand forecasting and project information, and the improved processes was also designed to implement them. Through the result of this study, it is expected that integrated management of public SW projects will be possible.

• Journal of Digital Convergence
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• v.15 no.12
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• pp.293-301
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• 2017

Most new products not only suddenly disappear in the market but also quickly cannibalize older products. Under such a circumstance, retailers may have too much stock, and customers may be faced with difficulties discovering products suitable to their preferences among short life cycle products. To address these problems, recommender systems are good solutions. However, most previous recommender systems had difficulty in reflecting changes in customer preferences because the systems employ static customer preferences. In this paper, we propose a recommendation methodology that considers dynamic customer preferences. The proposed methodology consists of dynamic customer profile creation, neighborhood formation, and recommendation list generation. For the experiments, we employ a mobile image transaction dataset that has a short product life cycle. Our experimental results demonstrate that the proposed methodology has a higher quality of recommendation than a typical collaborative filtering-based system. From these results, we conclude that the proposed methodology is effective under conditions where most new products have short life cycles. The proposed methodology need to be verified in the physical environment at a future time.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1282-1288
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• 2011

Recently, the demand regarding reliability and safety of the railroad are increased as built to high-speed railway and Driverless LRT systems. Accordingly, effective management of construction projects is being applied, with the introduction and use of PMIS computerized systems. Due to the construction of railways, from the start of PMIS research planning, design, procurement, to construction and commissioning, various expertise is being carefully gathered, and by integrating it into the unified budget ideas and processes, rational, efficient, organized, and manageable financial plans are developed for the computerized system. However, the current PMIS does not take into account the life-cycle. Therefore, this study is to bring attention to the BIM smart BOM-based configuration management for life-cycle through the consideration for railway construction project management.

• Steel and Composite Structures
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• v.29 no.3
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• pp.287-299
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• 2018

The purpose of this study is to investigate the effectiveness of damped cable systems (DCS) to mitigate the earthquake-induced responses of a building frame structure. The seismic performance of the DCS is investigated using the fragility analysis and life cycle cost evaluation of an existing building retrofitted with the DCS, and the results are compared with the structure retrofitted with conventional fluid viscous dampers. The comparison of the analysis results reveals that, due to the self-centering capability of the DCS, residual displacement approximately reaches to zero for the structure retrofitted with the DCS. The fragility analysis shows that the structure retrofitted with the DCS has the least probability of reaching the specific limit states compared to the bare structure and the structure with the conventional fluid viscous damper (VD), especially under the severe ground motions. It is also observed that both the initial and the life cycle costs of the DCS seismic retrofitting technique is lesser compare to the structure retrofitted with the VD.

• Journal of Korean Society of Transportation
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• v.18 no.1
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• pp.7-15
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• 2000

물류에서는 재화 또는 정보의 흐름이 매우 중요하다. 그 동안 우리나라에서는 물류시스템을 물리적인 시설로 간주 시설의 공급에만 관심을 기울여 왔다. 그 결과 물류활동을 지원할 수 있을 만한 정보시스템의 구축이 충분히 이루어지지 못하였다. 본 연구에서는 화물운송을 위주로 한 화물유통체계의 합리화 방안을 모색하기 위하여 교통부분과 밀접한 연계를 갖는 첨단화물운송체계의 도입효과를 논의하고 Life-Cycle Cost의 개념을 이용하여 첨단화물운송체계의 시스템 대안을 평가하였다. 분석결과 노변 통신시스템을 이용한 시스템의 구성이 중장기적으로 유리한 것으로 평가되었다. 이는 통신비의 부담이 시설의 유지보수비의 부담보다 크기 때문이다. 그러나 노변통신시스템시설은 표준화 등의 문제로 아직 적용에 문제점들이 많으며 낙뢰 등 비용산정에 포함되지 못한 유지보수의 추가비용이 발생할 소지가 크다. 그러므로 교통시설의 특징에 따라 두 접근방식을 혼용하는 방안이 검토되어야 한다.