• Journal of the Society of Disaster Information
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• v.8 no.2
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• pp.119-137
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• 2012

In this study, the damages and condition of road pavement were analyzed using pavement management system (PMS) for the structural improvement. Problems of road pavement management were issued by in-depth interview with workers in charge of plant, construction and supervision. By surveying advanced road pavement management, the way how to improve road pavement management in Seoul was discussed. In conclusion, it is necessary to take measures against road heavy traffic and heavy rain in summer. It was found that the problem of early damages of road pavement due to uniform layout with analyzing life cycle cost (LCC). According to the results of survey, it was suggested to strength practical training and to control precisely the temperature of pavement in the process of production and construction.

• Magazine of the Korea Concrete Institute
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• v.11 no.1
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• pp.129-139
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• 1999

Recently, many strengthening methods are developed and used to rehabilitate existing structures. One of the old and popular methods is strengthening with bonding steel plate. However, steel plate bonding method has a defect, which is debonding failure of steel plate before yielding of the plate due to stress concentration at the of the bonded plate. The objective of this study is the experimental verification of the improved bonding properties of a strengthening plate with notches. Two normal beams and ten strengthened beams with steel plate, which have several different notches, are tested and showed their effectiveness. Test results show that the notches of strengthening plate significantly improve post-yielding behavior, compared to normally strengthened beams. It is proved that the notches of strengthening plate increases ultimate strength 14% more than normal strengthened beam after yield strength. As for the shape of notches, arc notch is the best. and triangle notch and trapezoidal notch are the next and end welding method has no effect.

• Korean Journal of Construction Engineering and Management
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• v.8 no.6
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• pp.129-138
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• 2007

According to the preceding research outcomes, feasibility studies on public construction projects were incorrect and subjective. To resolve the problems, Korean government initiated Preliminary Feasibility Study (PFS) system prior to undertaking the main feasibility study. The PSF can be categorized into four areas such as road, railroad, harbor, airport, and Culture & Tourism (C&T). Especially when it comes to complex due to the introduction of five-weekday working system and local $government^{\circ}{\phi}s$ self administrative system. As a result, the standardization and legislation of the PSF can not be operated effectively. Accordingly this paper seeks to 1) identify actual condition of conducted PSF in C&T; 2) set up analytical model considering cost factor of economical efficiency and seek obstacles of PSF system; 3) suggest improvement plan for construction PSF projects.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.5
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• pp.913-921
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• 2012

The current PC-based desktop environment is being converted into server-based virtual desktop environment due to security, mobility, and low upgrade cost. In this paper, a desktop virtualization system is implemented using an open source-based cloud computing platform and hypervisor. The implemented system is applied to the virtualziation of computer in university. In order to reduce the image transfer time, we propose a solution using HDFS. In addition, an image management structure needed for desktop virtualization is designed and implemented, and applied to a real computer lab which accommodates 30 PCs. The performance of the proposed system is evaluated in various aspects including implementation cost, power saving rate, reduction rate of license cost, and management cost. The experimental results showed that the proposed system considerably reduced the image transfer time for desktop service.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.04b
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• pp.917-920
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• 2001

워크플로우의 응용 분야 중에서 전자상거래의 B2B 나 B2C 에 적용하는 사례가 빈번히 발생하는 추세이다. 이에 따라 워크플로우 관리 시스템의 엔진의 구조 역시 변화가 이뤄져야 한다. 다수의 전자 상거래를 처리하기 위해서 시스템의 구성을 실행 객체가 아닌 데이터화를 시켰다. 이는 기존의 표준에서 제안된 구조와 다른 구조이다. 이를 통해 시스템의 부하와 비용을 줄이는 방법을 제시하고, 본 논문에서 제시한 엔진을 바탕으로 하는 워크플로우 관리 시스템을 소개한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2008.05a
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• pp.853-856
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• 2008

최근 모바일 기기 사용자의 수가 증가함에 따라 모바일 기기 사용자의 위치정보를 관리하기 위한 기법들이 활발히 연구되고 있다. 기존의 모바일 시스템에서 위치정보를 관리하기 위한 방법으로 two-tier 방식과 two-tier 방식을 개선한 구조적 기법이 제시되었다. 구조적 기법에서는 어떻게 위치 데이터베이스를 군집화시키는 것이 매우 중요하다. 왜냐하면 데이터베이스를 군집하는 방법에 따라 업데이트 비용의 차이가 크기 때문이다. 구조적 기법을 위한 이전 연구는 set-cover 알고리즘을 기반한 bottom-up 방식의 시스템 이다. 본 논문에서는 구조적 기법의 데이터베이스 군집화를 위해 K-means clustering 알고리즘을 기반한 top-down 방식의 시스템을 사용하였고, 실험을 통해 본 논문에서 제시된 방식의 시스템이 기존 방식의 시스템보다 데이터베이스 업데이트측면에서 13.67%의 성능이 향상되었음을 보였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.1A
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• pp.49-53
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• 2012

Coastal structures, constructed for preventing coastal slope erosion, often causes the scour on the boundary between the coastal structure and the sea-bed, which might lead to collapse of coastal structures. To prevent the collapse, the usual upright block type coastal structures can be modified to other forms or systems of coastal structures. To validate the performance of the proposed systems, it is necessary to conduct high cost hydraulic experiments. If numerical modeling can be performed prior to the hydraulic experiments and the performance of the proposed systems is analyzed numerically in advance, the expenses can be reduced significantly by optimizing the number of cases for conducting the experiments. In this study, a fluid-structure interaction analysis procedure is proposed for modeling the hydraulic experiments of costal structures using the finite element package, LS-DYNA. As can be found in the usual hydraulic experiments, fluid velocities of potential scour locations are monitored and analyzed in detail for four types of coastal structures, block, step, trapezoid and rubble mound.

• Journal of Digital Contents Society
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• v.19 no.1
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• pp.173-179
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• 2018

With the recent increase in the number of cars and the lack of parking spaces, the number of parking businesses has increased. the parking management has become an essential element in parking business, and the parking management's company becomes an increasingly popular opportunity. However, as competition grows as more and more and companies increase in number, efforts are being made to create new services, gain technological excellence, or reduce costs through current system improvements. In this paper, we developed a parking management system using cloud based LPR(License Plate Recognition) service for effective parking. Structural improvements in the proposed system reduce costs, simplify installation, and respond quickly to failures and updates.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.4
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• pp.109-120
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• 2007

In this study, a bridge maintenance system is developed to generate performance-based optimum maintenance strategy by considering the life-cycle cost. A multi-objective combinatorial optimization problem is formulated to generate a tradeoff maintenance scenarios which satisfies the balance among the conflicting objectives such as the performance and cost during the bridge lifetime and a genetic algorithm is applied to the system. By using the developed program, this study proposes a process of optimum maintenance scenario applying to the steel girder bridge of national road. The developed system improves the current methods of establishing the bridge maintenance strategy and can be utilized as an efficient tool to provide the optimum bridge maintenance scenario corresponding to the various constraints and requirements of bridge agency.

• The monthly packaging world
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• s.187
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• pp.48-61
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• 2008

'생산자책임재활용제도'는 제품생산자나 포장재를 이용한 제품의 생산자에게 그 제품이나 포장재의 폐기물에 대하여 일정량의 재활용의무를 부여하여 재활용하게 하고, 이를 이행하지 않을 경우 재활용에 소요되는 비용 이상의 재활용 부과금을 생산자에게 부과하는 제도이다. EPR(Extended Producer Responsibility)의 개념은 종전의 생산자들은 재활용이 쉬운 재질 구조의 제품을 생산하여 이를 판매하는 시점까지만 책임을 지고, 사용 후 발생된 폐기물은 소비자의 책임이었으나, 이제는 사용 후 발생되는 폐기물의 재활용까지 생산자의 책임으로 범위를 확대한다는 의미로 자리매김하고 있다. 우리나라의 경우 완전히 새로운 개념의 제도가 아니라 이미 생산자책임원칙에 의해 '92년부터 운영해 오고 있는 예치금제도를 보완 개선하여 '03. 1. 1일부터 시행하고 있는 상황이다. 본 고에서는 EPR 제도의 현황 및 성과에 대해 포장재 재활용을 중심으로 살펴보도록 한다.