• 한국환경과학회지
• /
• 제22권12호
• /
• pp.1579-1587
• /
• 2013

This study was performed to evaluate the asbestos exposure levels and to calculate excess lifetime cancer risk (ELCR) for the risk assessment of the asbestos fibers released from asbestos-cement slate roofing (ASR) building. Total number of ASR buildings was into 21,267 in Busan, and 82.03 percent of the buildings was residential houses, and 43.61 percent of the buildings was constructed in 1970s. For this study, ten buildings were selected randomly among the ASR buildings. The range of airborne asbestos concentration in the selected ten ASR buildings was from 0.0016 to 0.0067 f/mL, and the concentration around no-admitted ASR buildings was higher than that around admitted buildings. The ELCR based on US EPA IRIS (integrated risk information system) model is within 3.5E-05 ~ 1.5E-04 levels, and the ELCR of no-admitted ASR buildings was higher than 1.0E-04 (one person per million) level that is considered a more aggressive approach to mitigate risk. These results indicate that the cancer risk from ASR buildings is higher than other buildings, and systematic public management is required for control of no-admitted ASR buildings within near future.

• 한국지리정보학회지
• /
• 제17권3호
• /
• pp.160-174
• /
• 2014

본 연구의 목적은 광역의 일단위 수문순환을 모의할 수 있는 격자기반의 분포형 모델을 구축한 후, 이를 미래 기후변화에 따른 광역적 수문영향을 평가하는데 있다. 격자별로 지표 유출층, 지표하 불포화 및 포화 토양층의 3단으로 구성하여 일별 물수지를 계산하며, 증발산량은 Penman-Monteith방법을 사용하였고, 지표 및 지표하유출은 지체계수(lag coefficient)와 감수곡선 계수(recession curve slope)를 적용하였다. 모델의 검보정을 위하여 한강유역의 충주댐과 소양강댐을 대상으로 9개년(2001-2009)의 댐유입량 자료를 이용하여 모델의 6개 주요매개변수를 보정하였으며, Nash-Sutcliffe 모델효율 (NSE)은 각각 0.57, 0.71의 값을 보였으며, 결정계수($R^2$)는 각각 0.65, 0.72의 값을 보였다. 5개의 IPCC SRES A1B 기후변화 시나리오자료(CSIRO MK3, GFDL CM2_1, CONS ECHO-G, MRI CGCM2_3_2, UKMO HADGEMI)를 적용한 결과, 미래 유출량의 변화는 강수량과 비슷한 경향을 보이면서 전체적으로 7.0%~27.1% 증가하였고, 증발산량도 미래 기온의 증가경향으로 일부 경우를 제외하고 증가하는 경향을 나타내었으며, 이들의 공간적 변화를 제시하였다.

• 한국습지학회지
• /
• 제16권1호
• /
• pp.73-83
• /
• 2014

최근 정부에서는 영산강 하구역 수질환경의 현재 상황 파악 및 미래 상황 예측을 위하여 모니터링 및 모델 연구를 진행 중에 있다. 그러나 모니터링 및 모델 자료는 대부분 수치 및 문자 형태로 이루어져 있어 사용자들의 이해도가 떨어지는 실정이다. 따라서 본 연구에서는 하구역 수질환경의 현재 상황 파악 및 미래 상황 예측을 지원할 수 있는 GIS기반 통합정보시스템을 개발하였다. 시스템 개발을 지원하기 위하여 모니터링 및 모델 DB 수집, 모델 연계 방안 마련, 시스템 GUI 및 개발환경 정의, 시스템 구성 등을 수행하였다. 모니터링 자료는 2010 ~ 2012년 영산강 하구역을 대상으로 실시된 관측값을 사용하였으며, 모델 자료는 유역 지역을 모의하기 위한 HSPF(Hydrological Simulation Program-Fortran) 모델과 하천 및 하구 지역을 모의하기 위한 EFDC(Environmental Fluid Dynamics Code) 모델 자료를 사용하였다. 최종적으로 모니터링 및 모델 자료를 시스템에 적용하여 관리 및 표출 방안에 대하여 제시하였다. 본 연구를 통해 개발된 시스템은 영산강 하구역 수질환경을 정량적으로 파악 및 예측하는데 지원할 수 있으며, 지도 기반 환경에 모니터링 및 모델 자료를 표출함으로써 사용자의 공간적 이해도를 높였다. 향후에는 영산강 하구역 수질환경 문제점에 대처 가능한 의사결정지원시스템으로 고도화하여 환경 평가 및 정책 수립에 지원할 수 있을 것으로 기대된다.

• 한국수학교육학회지시리즈A:수학교육
• /
• 제44권3호
• /
• pp.375-396
• /
• 2005

This paper reports on the main results of 3 study that compared students' beliefs, skills, and understandings in an innovative approach to differential equations to more conventional approaches. The innovative approach, referred to as the Realistic Mathematics Education Based Differential Equations (IODE) project, capitalizes on advances within the discipline of mathematics and on advances within the discipline of mathematics education, both at the K-12 and tertiary levels. Given the integrated leveraging of developments both within mathematics and mathematics education, the IODE project is paradigmatic of an approach to innovation in undergraduate mathematics, potentially sewing as a model for other undergraduate course reforms. The effect of the IODE projection maintaining desirable mathematical views and in developing students' skills and relational understandings as judged by the three assessment instruments was largely positive. These findings support our conjecture that, when coupled with careful attention to developments within mathematics itself, theoretical advances that initially grew out research in elementary school classrooms can be profitably leveraged and adapted to the university setting. As such, our work in differential equations may serve as a model for others interested in exploring the prospects and possibilities of improving undergraduate mathematics education in ways that connect with innovations at the K-12 level

• Nuclear Engineering and Technology
• /
• 제48권5호
• /
• pp.1192-1205
• /
• 2016

Field programmable gate array (FPGA)-based systems are thought to be a practical option to replace certain obsolete instrumentation and control systems in nuclear power plants. An FPGA is a type of integrated circuit, which is programmed after being manufactured. FPGAs have some advantages over other electronic technologies, such as analog circuits, microprocessors, and Programmable Logic Controllers (PLCs), for nuclear instrumentation and control, and safety system applications. However, safety-related issues for FPGA-based systems remain to be verified. Owing to this, modeling FPGA-based systems for safety assessment has now become an important point of research. One potential methodology is the dynamic flowgraph methodology (DFM). It has been used for modeling software/hardware interactions in modern control systems. In this paper, FPGA logic was analyzed using DFM. Four aspects of FPGAs are investigated: the "IEEE 1164 standard," registers (D flip-flops), configurable logic blocks, and an FPGA-based signal compensator. The ModelSim simulations confirmed that DFM was able to accurately model those four FPGA properties, proving that DFM has the potential to be used in the modeling of FPGA-based systems. Furthermore, advantages of DFM over traditional reliability analysis methods and FPGA simulators are presented, along with a discussion of potential issues with using DFM for FPGA-based system modeling.

• Advances in environmental research
• /
• 제2권4호
• /
• pp.279-290
• /
• 2013

In this study, a comprehensive model developed to estimate greenhouse gas (GHG) emissions from urban area with low impact development (LID) and its integrated management practices (IMPs). The model was applied to the actual urban area in Asan Tangjeong district (ATD) as a case study. A rainwater tank (1200 ton) among various LID IMPs generated the highest amount of GHG emissions ($3.77{\times}10^5kgCO_2eq$) and led to the utmost reducing effect ($1.49{\times}10^3kgCO_2eq/year$). In the urban area with LID IMPs, annually $1.95{\times}104kgCO_2eq$ of avoided GHG emissions were generated by a reducing effect (e.g., tap water substitution and vegetation $CO_2$ absorption) for a payback period of 162 years. A sensitivity analysis was carried out to quantitatively evaluate the significance of the factors on the overall GHG emissions in ATD, and suggested to plant alternative vegetation on LID IMPs.

• Journal of Information Technology Applications and Management
• /
• 제12권2호
• /
• pp.129-143
• /
• 2005

In recent years, two major streams in medical information systems are：1) system integration among OCS(Order Communication System), EMR(Electronic Medical Record), PACS(Picture Archiving and Communication System), and ERP(Enterprise Resource Planning) and 2) system integration through medical collaboration between East and West medical service providers. One of the characteristics which differentiate the Korean medical industry from the western medical industry is the East-West medical collaboration. In many respects there are many differences between East and West medical treatment. Although East and West medical treatment have developed from different medical philosophies and standards, we assume that the better medical care can be provided by integrating their medical procedures effectively. The two possible approaches to the integration of East and West medical information systems are suggested in this paper：One is loosely coupled model and the other is tightly coupled model. EMR improves the quality of medical record which reflects the quality of clinical practice. It provides more efficient and convenient way of input, retrieval, storage, communication and management of medical data. We abstracted the standard medical procedures from the two medical procedures performed in Daejeon Oriental Hospital and Hehwa Clinic at Daejeon University and also abstracted database schema by analyzing the characteristics of information needed in East-West medical collaboration. Our EMR is composed of two types of data：one is structured data and the other is unstructured data, which are formalized by SOAP(Subjective, Objective, Assessment, Plan) format. Currently the integrated system is implemented and operated successfully for six months.

• 한국물환경학회지
• /
• 제36권6호
• /
• pp.592-610
• /
• 2020

In South Korea, the concept of water environment was expanded to include aquatic ecosystems with the Integrated Water Management implementation. Watershed-scale modeling is typically performed for hydrologic component analysis, however, there is a need to expand to include ecosystem variability such that the modeling corresponds to the social and political issues around the water environment. For this to be viable, the modeling must account for several distinct features in South Korean watersheds. The modeling must provide reasonable estimations for peak flow rate and apply to paddy areas as they represent 11% of land use area and greatly influence groundwater levels during irrigation. These facts indicate that the modeling time intervals should be sub-daily and the hydrologic model must have sufficient power to process surface flow, subsurface flow, and baseflow. Thus, the features required for watershed-scale modeling are suggested in this study by way of review of frequently used hydrologic models including: Agricultural Policy/Environmental eXtender(APEX), Catchment hydrologic cycle analysis tool(CAT), Hydrological Simulation Program-FORTRAN(HSPF), Spatio-Temporal River-basin Ecohydrology Analysis Model(STREAM), and Soil and Water Assessment Tool(SWAT).

• 환경영향평가
• /
• 제28권2호
• /
• pp.141-151
• /
• 2019

우리나라는 2015년 환경오염시설의 통합관리에 관한 법률을 통과시켜서 BAT 기준서에 의한 통합환경관리가 실시중이다. 통합환경관리의 성격을 요약하면 다오염물질 배출원에 대한 관리의 통합화와 BAT 로 대변되는 기술적 기준에 의한 규제이다. 일반적으로 경제학에서는 기술기준에 의한 규제는 정태적 동태적 비효율성을 가져오는 것으로서 회피하여야 할 정책수단으로 알려져 있다. 통합환경관리제도는 BAT규제를 바탕으로 운용되는데 이에 대한 경제적 효율성 역시 심각한 의문의 대상이 될 수 있다. 본 논문은 BAT 기준의 효율성을 경제학적 관점에서 평가하고자 시도한다. 간단한 다오염물질 모형을 통하여 BAT 규제의 경제적 효율성을 분석하여 본 결과 단일오염물질상황에서도 정보의 불완전성으로 인하여 약하게 존재하던 환경세의 BAT 대비 비효율성이 다오염물질 상황하에서는 더욱 커짐을 보여주었다. 다오염물질관리체계로서 IPPC와 BAT가 한 묶음으로 추진되고 실행되어온 이유가 이러한 사실에 의하여 부분적으로 설명된다. EU에서 석탄 상대가격의 하락으로 대기오염물질의 배출 증대가 우려되는 상황에서 BAT 기준의 강화로 대처한 것이 가격구조와 실효적 환경세의 변동으로 인한 환경적 후생손실을 BAT 규제 등으로 대처한 사례 중의 하나로 볼 수 있다.

• 해양환경안전학회지
• /
• 제19권3호
• /
• pp.290-301
• /
• 2013

The docking analysis of a global ship structure is requested to evaluate its structural safety against the reaction forces at supports during docking works inside a dry dock. That problem becomes more important recently as the size of ships is getting larger and larger. The docking supports are appropriately arranged in a dock to avoid their excessive reaction forces which primarily cause the structural damages in docking a ship and, up to now, the structural safety has been assessed against the support arrangement by the finite element analysis (FEA) of a global ship structure. However, it is complicated to establish the finite element model of the ship in the current structural design environment of a shipyard and it takes over a month to finish the work. This paper investigates a simple and fast approach to carry out a ship docking analysis by a simplified grillage model and to assign the docking supports position on the model. The grillage analysis was considered from the motivation that only the reaction forces at supports are sufficient to assess their arrangement. Since the simplified grillage model of the ship cannot guarantee its accuracy quantitatively, modeling strategies are proposed to improve the accuracy. In this paper, comparisons between the proposed approach and three-dimensional FEA for typical types of ships show that the results from the present grillage model have reasonably good agreement with the FEA model. Finally, an integrated program developed for docking supports planning and its evaluation by the proposed approach is briefly described.