• 대한토목학회논문집
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• 제29권1D호
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• pp.73-80
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• 2009

열화된 콘크리트 구조물 보수에 있어, 보수재를 사용하기 전에 열화부위는 완전히 제거되어야 한다. 워터제트 공법은 열화된 콘크리트를 제거하는 방법 중에 하나로 철근 및 건전한 콘크리트에 손상을 주지 않으면서 손상된 콘크리트를 제거할 수 있는 매우 효과적인 방법으로 알려져 있다. 이러한 워터제트의 사용은 표면요철형성 등으로 신구 콘크리트의 부착력을 향상 시킨다. 본 연구에서는 국내에서 적용되고 있는 워터제트 장비를 사용하여 콘크리트 슬래브 강도에 변화를 주어 파쇄깊이에 따른 강도추정식을 제안하고 하였으며 이를 통해 워터제트 관련 규정제안 및 보수보강 시 사용되고 워터제트 장비에 대한 기초적인 정보를 제공하고자 한다.

• 대기
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• 제23권1호
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• pp.93-102
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• 2013

Atmospheric transport pathway of an air mass is an important constraint controlling the chemical properties of the air mass observed at a designated location. Such information could be utilized for understanding observed temporal variabilities in atmospheric concentrations of long-lived chemical compounds, of which sinks and/or sources are related particularly with natural and/or anthropogenic processes in the surface, and as well as for performing inversions to constrain the fluxes of such compounds. The Lagrangian particle dispersion model FLEXPART provides a useful tool for estimating detailed particle dispersion during atmospheric transport, a significant improvement over traditional "single-line" trajectory models that have been widely used. However, those without a modeling background seeking to create simple back-trajectory maps may find it challenging to optimize FLEXPART for their needs. In this study, we explain how to set up, operate, and optimize FLEXPART for back-trajectory analysis, and also provide automatization programs based on the open-source R language. Discussions include setting up an "AVAILABLE" file (directory of input meteorological fields stored on the computer), creating C-shell scripts for initiating FLEXPART runs and storing the output in directories designated by date, as wells as processing the FLEXPART output to create figures for a back-trajectory "footprint" (potential emission sensitivity within the boundary layer). Step by step instructions are explained for an example case of calculating back trajectories derived for Anmyeon-do, Korea for January 2011. One application is also demonstrated in interpreting observed variabilities in atmospheric $CO_2$ concentration at Anmyeon-do during this period. Back-trajectory modeling information introduced in this study should facilitate the creation and automation of most common back-trajectory calculation needs in atmospheric research.