• Title/Summary/Keyword: 지표경계조건

Search Result 78, Processing Time 0.027 seconds

An Experimental Study on a Sea Water Infiltration Control via Pumping of Salt Water at Coastal Aquifer and Calculation of the Maximum Possible Amount of Pumping (해안대수층에서 염수 양수를 통한 염수 침투 제어 및 가능 최대 담수 양수량 산정에 관한 실험적 연구)

  • Suh, Seong-Kook;Oh, Chang-Moo;Kim, Won-Il;Ho, Jung-Seok;Ahn, Won-Sik
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2010.05a
    • /
    • pp.2001-2006
    • /
    • 2010
  • 본 연구에서는 수리모형실험을 통해 해안지역 대수층에서 해수침투가 일어나지 않는 지하수의 최적 양수량을 산정하였다. 해안 대수층 및 양수정을 구현하기 위해 가로 140 cm, 세로 70 cm, 두께 10 cm 의 직사각형 Sandtank 모형과 5 mm 원형관을 이용하여 수행하였다. 해수의 염도, 해안가의 지표경사 등을 기준으로 설정하였으며, 다공질 매체의 입자크기에 따른 수리전도도 2가지를 경계조건으로 하여 각각의 양수정 위치에 따라 최대 담수량을 모의하였으며, 이 때, 하나의 과잉 담수량에 따른 최적 염수량을 산정하여 염수침투 제어 효과를 검증하였다. 다공질매체의 수리전도도가 높을수록 최대 담수량이 증가되며 이에 따라 염수 침투 제어를 위한 최적염수량이 증가하였다. 또한 양수정의 위치가 염수조에 가까울수록 최대담수량 및 최적염수량이 감소되었다. 이러한 모의를 통하여 설정된 각각의 양수정 위치에서 최적의 염수량으로 염수침투를 제어함으로써 지속시간 이용가능한 최대담수량을 나타내었다.

  • PDF

Systematic Approach to The Extraction of Effective Region for Tongue Diagnosis (설진 유효 영역 추출의 시스템적 접근 방법)

  • Kim, Keun-Ho;Do, Jun-Hyeong;Ryu, Hyun-Hee;Kim, Jong-Yeol
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.45 no.6
    • /
    • pp.123-131
    • /
    • 2008
  • In Oriental medicine, the status of a tongue is the important indicator to diagnose the condition of one's health like the physiological and the clinicopathological changes of internal organs in a body. A tongue diagnosis is not only convenient but also non-invasive, and therefore widely used in Oriental medicine. However, the tongue diagnosis is affected by examination circumstances like a light source, patient's posture, and doctor's condition a lot. To develop an automatic tongue diagnosis system for an objective and standardized diagnosis, segmenting a tongue region from a facial image captured and classifying tongue coating are inevitable but difficult since the colors of a tongue, lips, and skin in a mouth are similar. The proposed method includes preprocessing, over-segmenting, detecting the edge with a local minimum over a shading area from the structure of a tongue, correcting local minima or detecting the edge with the greatest color difference, selecting one edge to correspond to a tongue shape, and smoothing edges, where preprocessing consists of down-sampling to reduce computation time, histogram equalization, and edge enhancement, which produces the region of a segmented tongue. Finally, the systematic procedure separated only a tongue region from a face image with a tongue, which was obtained from a digital tongue diagnosis system. Oriental medical doctors' evaluation for the results illustrated that the segmented region excluding a non-tongue region provides important information for the accurate diagnosis. The proposed method can be used for an objective and standardized diagnosis and for an u-Healthcare system.

Regional Climate Simulations over East-Asia by using SNURCM and WRF Forced by HadGEM2-AO (HadGEM2-AO를 강제자료로 사용한 SNURCM과 WRF의 동아시아 지역기후 모의)

  • Choi, Suk-Jin;Lee, Dong-Kyou;Oh, Seok-Geun
    • Journal of the Korean earth science society
    • /
    • v.32 no.7
    • /
    • pp.750-760
    • /
    • 2011
  • In this study, the reproducibility of the simulated current climate by using two regional climate models, such as Seoul National University Regional Climate Model (SNURCM) and Weather Resuearch and Forecasting (WRF), is evaluated in advance to produce the standard regional climate scenario of future climate. Within the evaluation framework of a COordinated Regional climate Downscaling EXperiment (CORDEX), 28-year-long (1978-2005) regional climate simulation was conducted by using the Hadley Centre Global Environmental Model (HadGEM2-AO) global simulation data of the National Institute of Meteorological Research (NIMR) as a lateral boundary forcing. The simulated annual surface temperatures were in good agreement with the observation; the spatial correlation coefficients between each model and observation were over 0.98. The cold bias, however, were shown over the northern boundary in the both simulated results. In evaluation of the simulated precipitation, the skill was reasonable and good. The spatial correlation coefficients for the precipitation over the land area were 0.85 and 0.79 in SNURCM and WRF, respectively. It is noted that two regional climate models (RCMs) have different characteristics for the distribution of precipitation over equatorial and midlatitude areas. SNURCM shows better distribution of the simulated precipitation associated with the East Asia summer monsoon in the mid-latitude areas, but WRF shows better in the equatorial areas in comparison to each other. The simulated precipitation is overestimated in summer season (JJA) rather than in spring season (MAM), whereas the spatial distribution of the precipitation in spring season corresponds to the observation better than in summer season. Also the RCMs were capable of reproducing the annual variability of the maximum amount and its timing in July, in which the skills over the inland area were in better agreement with the observation than over the maritime area. The simulated regional climates, however, have the limitation to represent the number of days for extremely hot temperature and heavy rainfall over South Korea.

Preliminary Study for Tidal Flat Detection in Yeongjong-do according to Tide Level using Landsat Images (Landsat 위성을 이용한 조위에 따른 영종도 갯벌의 면적 탐지에 관한 선행 연구)

  • Lee, Seulki;Kim, Gyuyeon;Lee, Changwook
    • Korean Journal of Remote Sensing
    • /
    • v.32 no.6
    • /
    • pp.639-645
    • /
    • 2016
  • Yeongjong-do is seventh largest island in the west coast of Korea which is 4.8 km away in the direction of south-west from Incheon. The mudflat area around the Yeongjong-do has variable dimension according to tide level. In addition, Yeongjong-do is important area with high environmental value as wintering sites for migratory birds. The mudflat of Yeongjong-do is also meaningful region because it is used as place of education and tourist attraction. But, there are increasing concerns about preservation of mudflat area caused by artificial development such as land reclamation project and Incheon airport construction. In this paper, mudflat area was detected using Landsat 7 ETM+ images that United States Geological Survey (USGS) is providing the data in 16 days period. The false color composite was made from band 7, 5, and 3 that could dividing boundary between water and land for the purpose of appearance of boundary line in mudflat region. This area was calculated using results of classification based on false color composite images and was digitized through repetitive algorithm during research of period. Therefore, the change of northeastern area in Yeongjong-do was detected according to tide level during 16 years from 2000 to 2015 on the basis of providing period at tide station. This paper will expect as indicator for range of area in same tide level prior to the start of the research for preservation of mudflat. It will be also scientific grounds about change of mudflat area caused by artificial development.

A Basic Study on the Evaluation Index of the Crime Prevention through Environmental Design of Wooden Cultural Buildings (목조 건축문화재의 범죄예방환경설계 평가지표에 대한 기초연구)

  • Kim, Choong-sik
    • Korean Journal of Heritage: History & Science
    • /
    • v.48 no.3
    • /
    • pp.4-29
    • /
    • 2015
  • To protect cultural heritages from damage and destruction, evaluating the crime prevention environments is considered extremely important. This study analyzed the crime patterns related to cultural heritages, classified the crime environments by their types, and deduced the elements of the CPTED(Crime Prevention Through Environment Design), aiming to present the indices for evaluating the crime prevention environments. The results of this study can be summarized as follows. First, the crimes related to cultural heritages that must be prevented were identified as the night time trespassing and arson. According to the results of the analysis of external environments based on crime actions, the crime prevention environments of cultural heritages were classified into 10 types. Second, the important evaluation principles of the cultural heritage CPTED were the access control, surveillance reinforcement and the surrounding environment. Third, the access control that cover the internal region, boundary, external region and surroundings were classified into 22 indices. The surveillance reinforcement covers natural, organized and mechanical surveillance with 21 indices. Fourth, the applicability of the CPTED evaluation index was presented according to the types of the cultural crime prevention environments. The results confirmed that the maximum 43 indices were applicable to the seowon(lecture hall), hyanggyo(Confucian school), and gwana(district government office), and the minimum 10 indices, to the ramparts. Finally, the 43 indices were applied to Donam Seowon to validate their applicability. The results confirmed that most of the indices were applicable with the partial supplements. The evaluation index presented in this study is likely to contribute to studies in the cultural heritage CPTED field and to the protection of cultural heritages. Furthermore, this study is considered significant because it unleashed continuous concerns on and developments of CPTED. However, as the field survey to validate the applicability of the indices was limited to only one type, it may require further objective verification such as through an expert's examination of the validity and applicability of the evaluation index. In addition, to accommodate the index in related policies and systems, more precise verifications of the indices by type are considered necessary.

Groundwater Flow Modeling in the KURT site for a Case Study about a Hypothetical Geological Disposal Facility of Radioactive Wastes (방사성폐기물 지하처분장에 대한 가상의 사례 연구를 위한 KURT 부지의 지하수 유동 모의)

  • Ko, Nak-Youl;Park, Kyung Woo;Kim, Kyung Su;Choi, Jong Won
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.10 no.3
    • /
    • pp.143-149
    • /
    • 2012
  • Groundwater flow simulations were performed to obtain data of groundwater flow used in a safety assessment for a hypothetical geological disposal facility assumed to be located in the KURT (KAERI Underground Research Tunnel) site. A regional scale modeling of the groundwater flow system was carried out to make boundary conditions for a local scale modeling. And, fracture zones identified at the study site were involved in the local scale groundwater flow model. From the results of the local scale modeling, a hydraulic head distribution was indicated and it was used in a particle tracking simulation for searching pathway of groundwater from the location of the hypothetical disposal facility to the surface where the groundwater reached. The flow distance and discharge rate of the groundwater in the KURT site were calculated. It was thought that the modeling methods used in this study was available to prepare the data of groundwater flow in a safety assessment for a geological disposal facility of radioactive wastes.

A Study on the Evaluation of Wide-scale Site Suitability for Water-friendly Recreation Area Planning (친수 휴양활동공간 계획을 위한 광역수준의 부지 적합성 평가)

  • Cho, Hyun-Ju;Ra, Jung-Hwa;Lee, Hyun-Taek;Ku, Ji-Na
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.37 no.2
    • /
    • pp.1-13
    • /
    • 2009
  • The purpose of this study was to look into the feasibility of site suitability focused on the potential for environmentally- and water-friendly recreation area development in a wide area(Nakdong River 35km) and to study new methods for providing basic data in regard to the recreation planning over a wide area as well as in application to other sites. The results of this study are as follows. Through classification by mesh method, the site of this study was classified into 42 grids, and by means of the analysis of evaluation indicators, 20 indicators were established and sorted into 4 types of significant recreation activity. According to the results of the analysis for each recreation activity type, there were 8 essentials for water-friendly recreation activity types based on water use while water-friendly recreation types for static activity included 12 sub-essentials. As a result of the first evaluation(the minimum required evaluation) by each classified grid, 32 of the 42 total grids were implemented by the minimum requirements. These grids were usually distributed evenly through the whole site. In terms of the second evaluation(specific site evaluation) results, 6 grids were highly suitable for recreational nature experiences and landscape ecological learning, 4 grids for developing water-friendly recreation for exercise, 1 grid for building water-friendly recreation based on water use, and 4 grids for planning water-friendly recreation for static activity. The results of the grid evaluation of this study could be extended to contiguous grids or reduced. Actual planning for a water-friendly recreation area must change the grid shape or size through boundary adjustments.

Occurrences of Uranium and Radon-222 from Groundwaters in Various Geological Environment in the Hoengseong Area (횡성지역 다양한 지질환경에서 지하수 중 우라늄 및 라돈-222 산출특성)

  • Jeong, Chan Ho;Yang, Jae Ha;Lee, Yu Jin;Lee, Yong Cheon;Choi, Hyeon Young;Kim, Moon Su;Kim, Hyun Koo;Kim, Tae Seong;Jo, Byung Uk
    • The Journal of Engineering Geology
    • /
    • v.25 no.4
    • /
    • pp.557-576
    • /
    • 2015
  • Groundwaters in granite, gneiss, and two-mica granite formations, including faults, in the Hoengseong area are examined to determine the relationship between their uranium and radon-222 contents and rock types. The chemical compositions of 38 groundwater samples and four surface water samples collected in the study area were analyzed. Sixteen of the samples showing high uranium and radon-222 contents were repeatedly analyzed. Surface radioactivities were measured at 30 points. The uranium and radon-222 concentrations in the groundwater samples were in the ranges of 0.02-49.3 μg/L and 20-906 Bq/L, respectively. Four samples for uranium and 35 samples for radon had concentrations exceeding the alternative maximum contaminant level of the US EPA. The chemical compositions of groundwaters indicated Ca(Na)-HCO3 and Ca(Na)-NO3(HCO3+Cl) types. The pH values ranged from 5.71 to 8.66. High uranium and radon-222 contents in the groundwaters occurred mainly at the boundary between granite and gneiss, and in the granite area. The occurrence of uranium did not show any distinct relationship to that of radon-222. The radon-222, an inert gas, appeared to be dissolved in the groundwater of the aquifer after wide diffusion along rock fractures, having been derived from the decay of uranium in underground rocks. The results in this study indicate that groundwater of neutral or weakly alkaline pH, under oxidizing conditions and with a high bicarbonate content is favorable for the dissolution of uranium and uranium complexes such as uranyl or uranyl-carbonate.

A study on hydraulic back analysis for an urban tunnel site and stability analysis based on hydro-mechanical coupling analysis (도심지 터널 용출수 발생구간에서의 수리 역해석 및 수리-역학 연계해석을 통한 안정성 해석 연구)

  • Park, Inn-Joon;Song, Myung-Gyu;Shin, Uyu-Soung;Park, Yong-Su
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.10 no.4
    • /
    • pp.397-404
    • /
    • 2008
  • Excessive amount of groundwater flowed into tunnel, while constructing Incheon international airport railway. Tunnel passes under subway line no. 2 with only 1.76 m below. To protect the existing structure, TRcM excavation method was applied. As station and construction shaft are already constructed, which are located back and forth of TRcM section, 86.4 ton per day of groundwater inflow is against expectation. To identify mechanism of excessive water inflow, hydraulic back analyses were performed. Then, hydro-mechanical coupled analysis were also performed with the hydrogeologic parameters identified, whose results are investigated for checking the stability of adjacent structures to the tunnel under construction. And a number of mechanical analyses were also performed to check the hydro-mechanical coupling effect. The result from the mechanical analysis shows that subsidence and tunnel ceiling displacement will be 0.85 mm and 1.32 mm. The result of hydro-mechanical couple analysis shows that subsidence and maximum tunnel ceiling displacement will be 1.2 mm and 1.72 mm. Additional displacements caused by groundwater draw down were identified, however, displacement is minute.

  • PDF

Verification of the Contaminant Transport Numerical Model in Subsurface Soil (토양내 오염물이동 수치모델 검증)

  • Suh, Kyung-Suk;Kim, Eun-Han;Han, Moon-Hee;Lee, Chang-Woo
    • Journal of Radiation Protection and Research
    • /
    • v.27 no.1
    • /
    • pp.67-75
    • /
    • 2002
  • The groundwater flow and contaminant transport numerical models have been established for understanding the movement of pollutants in surface soil environment. The numerical solutions were compared with the analytic solutions for the verification and the application of the models. The numerical solutions from the groundwater and transport models agreed welt with analytic solutions. Especially, the results of groundwater flow model were validated in one- and two-dimensional heterogeneous media. Therefore, it will represent well the characteristics of the heterogeneous media in the field applications. Also, the phenomena of the pollutant dispersion represented quite well by the advection and the hydrodynamic dispersion in the results of the transport model. The important input factor is the choice of complicated boundary conditions in operating the numerical models. The numerical results are influenced by the choice of the proper boundary conditions.