• Journal of Korean Society of Water and Wastewater
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• v.25 no.5
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• pp.667-679
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• 2011

In this study, the influences of pollutant from Dae-po Stream and So-gam Stream located at the downstream of Nak-dong River on the water quality at Mul-geum water intake station were analyzed using RAMS model. Field measurements of velocity by ADCP, and water quality distribution of BOD and TP by water sampling were carried out to present the input and verification data for numerical simulations. The comparison between RAM2 and ADCP measurement, which aimed for the analysis of 2-D velocity distribution around Mul-geum water intake station showed that two results matched well along the spanwise direction. The prediction of pollutant concentration by RAM4 agreed fairly well with the measured data except for the points nearby right banks in the vicinity of tributary pollutant source. Flushing effect by the increase of mainstream discharge in Nak-dong River was analyzed to provide the damage mitigation in preparation for the accidental water pollution. With increasing mainstream discharge, high velocity and increased water quantity induced increasing dilution effect, thereby decreasing the inflow pollutant concentration rapidly.

• 한국IT서비스학회:학술대회논문집
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• 2007.11a
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• pp.364-369
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• 2007

다양한 의료서비스를 정형화되고 효율적인 방법으로 제공하기 위하여 최근 의료기관의 EMR(Electronic Medical Record; 전자의무기록) 시스템의 도입이 급속도로 확산되고 있다. 그러나 국내에서 구축되고 있는 EMR은 초기에 기대했던 EMR의 도입목적을 중분하게 달성하지 못하고 있다. 이는 근본적으로 EMR의 방향성과 구조에 한계를 지니고 있기 때문이다. 국내에서 구축되고 있는 대부분의 전자의무기록시스템은 자료수집원 지향 의무기록 (Source Oriented Medical Record; SOMR) 방식으로 개별 사실을 수집하고 제시하기 위한 관찰자 중심, 서식중심의 시스템이며 차트 이송과 종이를 없애는 것이 주목적이다. SOMR 방식은 EMR의 다양한 도입목적, 특히 임상자료의 효과적 활용을 충족시킬 수 없는 태생적인 한계를 지니고 있기 때문에 문제지향 의무기록 (Problem Oriented Medical Record; POMR) 방식의 EMR과 적절한 혼용전략 (Hybrid Strategy)이 절실히 요구된다. 본 연구의 목적은 SOMR 시스템과 POMR 시스템이 보완적으로 결합된 하이브리드 EMR 아키텍처를 제시하고 아키텍처를 구성하는 데 필요한 기술적 요소들과 그들간의 상호관계 틀 파악한 후 이를 기반으로 개발방법론을 도출하는 것이다. 또한 만성신부전증 환자 사례를 이용하여 앞서 제시된 개발방법론에 따라 프로토타입을 개발하였다. 본 연구는 EMR 시스템이 SOMR 구조에만 편향됨으로써 발생될 수 있는 다양한 문제들을 해결함으로써 진료의 품질 항상, 임상연구의 활성화, 조직적이고 과학적인 진료계획의 수립과 같은 소외되어 왔던 EMR의 목표를 실현할 수 있을 것으로 기대 된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.758-763
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• 2009

본 연구에서는 여주 외 5개 지점에서 유사 이동이 활발한 시기인 홍수기 및 저 평수기(홍수전 후)에 부유사와 하상토를 측정하고 이를 통해 유사량 특성을 파악하였다. 시료분석은 그 목적에 따라 여과법, BW관법, 체분석법으로 $Od{\acute{e}}n$ Curve와 입도분포곡선 등을 작성하여 총유사량 추정시 이용하였다. 또한 총유사량을 추정하는 데 있어 에너지 개념을 이용한 Ackers & White(1973년), Engelund & Hansen(1967년), Yang(1973년, 1979년)의 방법과 확산-이송 개념의 Modified Einstein(1955년) 방법을 적용하였다. 연구결과, 유량-부유사농도, 부유사량, 총유사량 관계에 있어 동일 유량에 대한 변동성과 추정방법에 따른 총유사량의 상충을 볼 수 있었다. 이는 강우사상별 특성 및 하천의 수리 및 유사특성에 따른 원인과 추정방법에 대한 서로 다른 제한된 범위의 자료들을 적용한 데에서 오는 오류로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.147-147
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• 2017

본 연구에서는 2003년 태풍 'MAEMI'에 의해 피해를 가장 많이 입은 경남 마산시를 중심으로 폭풍해일 범람도를 작성하였다. 해양과 하천 하류부가 만나는 마산시에서는 해일, 조석, 하천을 동시에 고려해야 하므로 이에 대한 단계적 적용을 통해 범람 중첩효과를 검토하였다. 본 연구에 사용된 수치모델은 네덜란드 Deltares사에서 개발한 준3차원 해수유동 모델 Delft3D이다. Delft3D는 폭풍해일 이외 지진해일, 부유물 이송, 오염물 확산 등 다양한 분야에 적용 가능하며, 파랑, 조석력, 바람에 의한 전단력, 온도, 염도에 의한 밀도류, 대기압 변화, 조간대 모의 등 다양한 영향을 고려할 수 있다. 수치모의시 모델의 안정성과 효율성을 높이기 위해 다중격자기법을 사용(최소 25m 격자)하였으며, 수심 자료는 국토지리정보원 수치지도와 국립해양조사원 수치해도의 수평 수직적 통합을 통해 구성하였다. 태풍 'MAEMI'의 Best Track은 기상청에서 제공하는 3시간 간격의 중심기압, 풍속, 중심위치를 Holland's Model에 적용하여 계산하였다. 조석효과를 고려하기 위해 개방경계에서 TPXO 7.2를 사용한 분조값을 입력하였다. 또한 하천의 흐름을 효과적으로 구현하기 위해 하천 단면에서의 동적 수위경계조건(또는 유량경계조건)을 추가적으로 부여하였다. 수치해석결과, 마산 수위 관측소에서 관측된 태풍 'MAEMI'의 해일고와 유사한 결과가 산출되었다. 범람역 해석결과는 해일, 조석, 하천을 동시적으로 고려하였을 경우에 실제 침수흔적도인 마산시재해침수지도와 가장 유사한 결과를 보였다.

• Journal of the Korean Society for information Management
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• v.37 no.4
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• pp.61-80
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• 2020

This study attempted to propose various application and function improvement plans by analyzing robots operated in the libraries. Thus, the types and functions of robots operated by 16 domestic and foreign libraries were examined. Most of them were used for Librarian Assistance (Book Inventory, Book Delivery, Etc.) and User Service (Facility Guide, Search Aids, Etc.). Besides, the introduction of robots in the National Library of Korea (NLK) and their functional limitations were analyzed. As a result, this study presented the need to develop additional functions for the robot, develop quarantine and security robots, the need for a national-level policy for robot diffusion, and build a robot ecosystem.

• Journal of the Korea institute for structural maintenance and inspection
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• v.15 no.1
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• pp.198-208
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• 2011

When a structure which has relatively low load constructs on soft clay, the bearing capacity of the ground will be improved by sand overlying clay. In this condition, verifying the bearing capacity is difficult from the P.B.T etcetera in the in-situ. So, it is needed to estimate precise bearing capacity in the design process. In this study, 2-dimensional chamber tests and FEM analyses are conducted to evaluate behavior of bearing capacity for shallow foundations on a sand overlying clay. Because depth ratio H/B and bearing capacity ratio $q_c/q_s$ are selected as main factors, height of a sand, undrained shear strength of a clay and width of a loading are designated as variables. Results from chamber tests are very similar with those of FEM analyses. And it shows that punching shear mechanism is more suitable than the equation of Okamura et al.(1998). To make continual application of load spread mechanism, the equivalent load spread angle is proposed for H/B and $q_c/q_s$. Also, the linear regression equation of critical depth ratio Hf is suggested for $q_c/q_s$.

• Fire Science and Engineering
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• v.30 no.3
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• pp.138-147
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• 2016

As services for citizens' security and protection offered at the national and social levels become more widely recognized across society, the more frequent use of ambulances by patients with both minor and major injuries is being observed. However, the number of safety accidents during transport by ambulances, which are responsible for the prompt transport of patients, has been rising in tandem with the increase in their use. This is due not only to their inconspicuousness both on the road and in other environments where these vehicles are exposed, but also to the high chance of secondary accidents, putting the lives of both patients and emergency responders at risk. It is important to study and develop designs that guarantee protection against safety accidents, noting that ambulances are completely exposed and unprotected on the road on cloudy days and at night-time. In addition, by identifying colors and design motives that enhance the conspicuity of ambulances from a distance and increase their security, emergency responders and patients can be safely protected, the identity of the ambulances can be reinforced and modernized, and the sense oppression which can be visually imposed on patients in a psychologically unstable condition can be eased. Against this backdrop, this study presents the process involved in deriving the exteriors of ambulances in Korea, including their colors and patterns, by examining the established global best practices and identifying the need for more studies into colors, even unconventional ones, that improve their safety.

• Journal of the Korean GEO-environmental Society
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• v.10 no.1
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• pp.5-14
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• 2009

This study is to analyze numerically the spatial behaviors of the solute transport in a spatially correlated variable-aperture fracture under the effective normal stress conditions. Numerical results show that the solute transport in a fracture is strongly affected by the spatial correlation length of apertures and applied effective normal stress. According to increasing spatial correlation length, the mean residence time of solute is decreased and the tortuosity and Peclet number (is a dimensionless number relating the rate of advection of a flow to its rate of diffusion) is also decreased. These results mean that the geometry of the aperture distribution is favorable to the solute transport as the spatial correlation length is increased. However, according to the applied effective normal stress is increased, the mean residence time and tortuosity have a tendency to increase but the Peclet number is decreased. The main reason that the Peclet number is decreased, is that the solute is displaced by one or two channels with relatively higher local flow rate due to the increment of contact areas by increasing effective normal stress. Moreover, based on numerical results of the solute transport in this study, the exponential-type correlation formulae between the mean residence time and the effective normal stress are proposed.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.12
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• pp.821-827
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• 2014

The 4major river project has caused changes in flow and water quality patterns in major rivers in Korea including the Nakdong River where several toxicant release accidents have had occurred. Three dimensional hydrodynamic model, the Environmental Fluid Dynamics Code (EFDC), was applied to evaluate the effect of geomorphological change of the river on the advection and dispersion patterns of a conservative toxic pollutant. A hypothetical scenario was developed using historical data by assuming a toxic release from an upstream location. If there is a toxic release at the Gumi Industrial Complex, the toxic material would be detected after 2.22 and 9.83 days at Chilgok and Gangjung weir, respectively, in the new river system. It was estimated that they took at least 12 times longer than those with the river conditions before the project. Effect of relocation of intake towers for Daegu Metro City to upstream of Gumi City was also evaluated using the developed modeling system. It was observed that hydraulic residence time would be increased due to decreased flow rate and thus due to lowered water level. However, peak concentration differences were found to be about 2% lower in both places due to increased dispersion effect after the relocation.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.23-27
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• 2008

The new conjunctive surface-subsurface flow model at a large scale was developed by using a 1-D Diffusion Wave (DW) model for surface flow interacting with the 3-D Volume Averaged Soil-moisture Transport (VAST) model for subsurface flow for the comprehensive terrestrial water and energy predictions in Land Surface Models (LSMs). A selection of numerical implementation schemes is employed for each flow component. The 3-D VAST model is implemented using a time splitting scheme applying an explicit method for lateral flow after a fully implicit method for vertical flow. The 1-D DW model is then solved by MacCormack finite difference scheme. This new conjunctive flow model is substituted for the existing 1-D hydrologic scheme in Common Land Model (CLM), one of the state-of-the-art LSMs. The new conjunctive flow model coupled to CLM is tested for a study domain around the Ohio Valley. The simulation results show that the interaction between surface flow and subsurface flow associated with the flow routing scheme matches the runoff prediction with the observations more closely in the new coupled CLM simulations. This improved terrestrial hydrologic module will be coupled to the Climate extension of the next-generation Weather Research and Forecasting (CWRF) model for advanced regional, continental, and global hydroclimatological studies and the prevention of disasters caused by climate changes.