• Title/Summary/Keyword: 교차 비교

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Estimation of design floods for ungauged watersheds using a scaling-based regionalization approach (스케일링 기법 기반의 지역화를 통한 미계측 유역의 설계 홍수량 산정)

  • Kim, Jin-Guk;Kim, Jin-Young;Choi, Hong-Geun;Kwon, Hyun-Han
    • Journal of Korea Water Resources Association
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    • v.51 no.9
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    • pp.769-782
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    • 2018
  • Estimation of design floods is typically required for hydrologic design purpose. Design floods are routinely estimated for water resources planning, safety and risk of the existing water-related structures. However, the hydrologic data, especially streamflow data for the design purposes in South Korea are still very limited, and additionally the length of streamflow data is relatively short compared to the rainfall data. Therefore, this study collected a large number design flood data and watershed characteristics (e.g. area, slope and altitude) from the national river database. We further explored to formulate a scaling approach for the estimation of design flood, which is a function of the watershed characteristics. Then, this study adopted a Hierarchical Bayesian model for evaluating both parameters and their uncertainties in the regionalization approach, which models the hydrologic response of ungauged basins using regression relationships between watershed structure and model. The proposed modeling framework was validated through ungauged watersheds. The proposed approach have better performance in terms of correlation coefficient than the existing approach which is solely based on area as a predictor. Moreover, the proposed approach can provide uncertainty associated with the model parameters to better characterize design floods at ungauged watersheds.

Convolutional Neural Networks for Rice Yield Estimation Using MODIS and Weather Data: A Case Study for South Korea (MODIS와 기상자료 기반 회선신경망 알고리즘을 이용한 남한 전역 쌀 생산량 추정)

  • Ma, Jong Won;Nguyen, Cong Hieu;Lee, Kyungdo;Heo, Joon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.34 no.5
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    • pp.525-534
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    • 2016
  • In South Korea, paddy rice has been consumed over the entire region and it is the main source of income for farmers, thus mathematical model for the estimation of rice yield is required for such decision-making processes in agriculture. The objectives of our study are to: (1) develop rice yield estimation model using Convolutional Neural Networks(CNN), (2) choose hyper-parameters for the model which show the best performance and (3) investigate whether CNN model can effectively predict the rice yield by the comparison with the model using Artificial Neural Networks(ANN). Weather and MODIS(The MOderate Resolution Imaging Spectroradiometer) products from April to September in year 2000~2013 were used for the rice yield estimation models and cross-validation was implemented for the accuracy assessment. The CNN and ANN models showed Root Mean Square Error(RMSE) of 36.10kg/10a, 48.61kg/10a based on rice points, respectively and 31.30kg/10a, 39.31kg/10a based on 'Si-Gun-Gu' districts, respectively. The CNN models outperformed ANN models and its possibility of application for the field of rice yield estimation in South Korea was proved.

The Influence of Cranial Cervical Ganglion Block in Beagle Dogs with Normal Intraocular Pressure (비글견에서 앞쪽목신경절 차단술이 정상 안압에 미치는 영향)

  • Park, Woo-Dae;Bae, Chun-Sik;Kim, Hwi-Yool
    • Journal of Life Science
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    • v.17 no.11
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    • pp.1472-1476
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    • 2007
  • This study was performed to observe changes of the intraocular pressure following cranial cervical ganglion block with the four different concentrations of lidocaine in beagle dogs with the normal intraocular pressure. We performed by the crossover test in ten beagle dogs divided into four groups, which were 2%, 1%, 0.5% and 0.25% lidocaine group. All experimental dogs received each four times cranial cervical ganglion block using 2 ml of lidocaine with the four different concentrations. The blocks were separately done at a week intervals in random order. Horner#s syndrome was observed in all groups. The intraocular pressure in the blocked side was significantly increased to 5 min in the 1% lidocaine group compared to the baseline (p<0.05). The intraocular pressure of 2% and 1% lidocaine groups were decreased between 25 and 45 min following cranial cervical ganglion block, while those of 0.5% and 0.25% lidocaine groups were unchanged. In conclusion, these results suggest that cranial cervical ganglion block affect on the change of intraocular pressure and 0.5% and 0.25% lidocaine are inadequate concentrations for the change of intraocular pressure in the dog with normal intraocular pressure.

Demonstration of Developed Numerical Procedure to Describe 3-dimensional Long-term Behavior of the Pleistocene Marine Foundations (Pleistocene 해저지반의 3차원 장기거동 해석을 위해 개발한 수치해석 기법의 입증)

  • Yun, Seong-Kyu
    • Journal of the Korean Geotechnical Society
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    • v.36 no.7
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    • pp.5-14
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    • 2020
  • Kansai International Airport (KIX) was opened in September 1994. Although 26 years have passed since the completion of the first island, long-term settlement is still in progress. This settlement occurs in the Pleistocene layer. For it is not easy to determine the permeability of the Pleistocene sand layer because the thickness and the degree of fine content in the horizontal direction are constantly changing. In addition, it is also a difficult to predict the interactive behavior of the ground due to the construction of the second phase island adjacent to it. In order to solve this problem, a two-dimensional finite element analysis considering elasto-viscoplastic was performed to evaluate the long-term deformation, including the interactive behavior of the alternating Pleistocene foundation due to the construction of two adjacent reclaimed islands. In general, two-dimensional analysis can be used when a section can represent the entire sections. However, Kansai Airport is an artificial reclaimed island so two-dimensional analysis cannot solve the problem such as the stress deformation in the corners of the island. Additionally, the structure of the actual sub-ground through physical exploration is non-homogeneity and its thickness is also not constant. Therefore, there are limitations for the two-dimensional analysis to explain the phenomena. That is, three-dimensional analysis is strongly required. Due to these demands, the author extended the existing two-dimensional program capable of elasto-viscoplastic analysis to three-dimensional and completed the verification of the three-dimensional program developed through one-dimensional consolidation analysis. In order to demonstrate the validity of the developed 3D program that has been verified, an analysis is performed under the same analysis conditions as the existing research using a two-dimensional program. The effectiveness of the developed 3D numerical analysis program was demonstrated by comparing the analysis results with the 2D results and actual measurement data.

User Perceptions of a Digital Archive for Content Creation: Focused on the Korea Creative Content Agency (KOCCA)'s 'Culturing' (창작 목적 디지털 아카이브 콘텐츠 활용에 대한 이용자 인식 연구 - 한국콘텐츠진흥원 컬처링(Culturing) 웹 사이트를 중심으로 -)

  • Park, Yong Min;Kim, Yang-woo
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.31 no.1
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    • pp.285-310
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    • 2020
  • A significant number of studies have been conducted on user perceptions of archive and record contents for the National Archives of Korea (NAK) and local record centers in the field of archives and records management in Korea. Yet, there has not been such a research on the use of digital archive contents designed for contents creation. Accordingly, this study investigated user perceptions of the use of the contents on the Korea Creative Content Agency (KOCCA)'s Culturing archive designed for creation purposes. A survey was conducted, examining the user's degree of interests, the expected user preference of the use and the expected extent of help by the contents of the archive. For the analyses of the survey data, this study performed one-way ANOVA for the comparative analyses of the means related to the subjects' general characteristics and the perceptions, along with cross-tabulation analyses for the association among the same items and nominal variables related to perceptions. On the basis of these analyses, this study suggests the following: ① to supplement the contents of the archive; ② to design customized interfaces and to enhance the readability; ③ to reinforce site PRs for large portal sites and creators' groups.

Intelligent Diagnosis Assistant System of Capsule Endoscopy Video Through Analysis of Video Frames (영상 프레임 분석을 통한 대용량 캡슐내시경 영상의 지능형 판독보조 시스템)

  • Lee, H.G.;Choi, H.K.;Lee, D.H.;Lee, S.C.
    • Journal of Intelligence and Information Systems
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    • v.15 no.2
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    • pp.33-48
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    • 2009
  • Capsule endoscopy is one of the most remarkable inventions in last ten years. Causing less pain for patients, diagnosis for entire digestive system has been considered as a most convenience method over a normal endoscope. However, it is known that the diagnosis process typically requires very long inspection time for clinical experts because of considerably many duplicate images of same areas in human digestive system due to uncontrollable movement of a capsule endoscope. In this paper, we propose a method for clinical diagnosticians to get highly valuable information from capsule-endoscopy video. Our software system consists of three global maps, such as movement map, characteristic map, and brightness map, in temporal domain for entire sequence of the input video. The movement map can be used for effectively removing duplicated adjacent images. The characteristic and brightness maps provide frame content analyses that can be quickly used for segmenting regions or locating some features(such as blood) in the stream. Our experiments show the results of four patients having different health conditions. The result maps clearly capture the movements and characteristics from the image frames. Our method may help the diagnosticians quickly search the locations of lesion, bleeding, or some other interesting areas.

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The Garden Drifts seen from Works by Gertrude Jekyll and Piet Oudolf (거투르트 지킬(Gertrude Jekyll)과 피에트 우돌프(Piet Oudolf)의 작품을 통해 본 정원의 드리프트 기법)

  • Park, Eun-Yeong
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.38 no.2
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    • pp.125-131
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    • 2020
  • In this study, the author comparatively analyzed the effects and applicability of drifts, one of planting design methods based on the principle of visual harmony, to look into the definition and characteristics in planing techniques with examples of drifts in gardens designed by Gerturde Jekyll and Piet Oudolf. Sites chosen for the case studies included Jekyll's Upton grey and Hestercomb garden and Oudolf's At Scampston Hall and Trentham Estate Garden. The results showed that Jekyll set layers for vertical and horizontal structures by using plants of different height to make flowers look like floating with their stems unseen and appear in turn over time. Assemble planting of groups was used to conceal rigid, irregular lines so that the plants are recognized as mass with smoother horizontal lines. Clearly visible, repeated drifts creates a sense of unity. Oudolf, in combining grass and perennial plants, used one-to-one correspondence or expansion to express drifts. Grass serves roles as a connecting material inserted when changing space or making transitions of images. Blocks in single species are repeatedly crossed to set scenes, and overlapping and mixing makes them more lively.

Effect of Joint Orientation Distribution on Hydraulic Behavior of the 2-D DFN System (절리의 방향분포가 이차원 DFN 시스템의 수리적 특성에 미치는 영향)

  • Han, Jisu;Um, Jeong-Gi
    • Economic and Environmental Geology
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    • v.49 no.1
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    • pp.31-41
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    • 2016
  • A program code was developed to calculate block hydraulic conductivity of the 2-D DFN(discrete fracture network) system based on equivalent pipe network, and implemented to examine the effect of joint orientation distribution on the hydraulic characteristics of fractured rock masses through numerical experiments. A rock block of size $32m{\times}32m$ was used to generate the DFN systems using two joint sets with fixed input parameters of joint frequency and gamma distributed joint size, and various normal distributed joint trend. DFN blocks of size $20m{\times}20m$ were selected from center of the $32m{\times}32m$ blocks to avoid boundary effect. Twelve fluid flow directions were chosen every $30^{\circ}$ starting at $0^{\circ}$. The directional block conductivity including the theoretical block conductivity, principal conductivity tensor and average block conductivity were estimated for generated 180 2-D DFN blocks. The effect of joint orientation distribution on block hydraulic conductivity and chance for the equivalent continuum behavior of the 2-D DFN system were found to increase with the decrease of mean intersection angle of the two joint sets. The effect of variability of joint orientation on block hydraulic conductivity could not be ignored for the DFN having low intersection angle between two joint sets.

Aquifer Characterization Using Seismic Data on the Aquistore CCS Project, Canada (캐나다 아퀴스토어 탄성파자료를 통한 이산화탄소 지중저장 연구지역 대수층 특성화)

  • Cheong, Snons;Kim, Byoung-Yeop;Shinn, Young Jae;Lee, Ho-Yong;Park, Myung-Ho
    • Economic and Environmental Geology
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    • v.47 no.6
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    • pp.625-633
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    • 2014
  • The Aquistore project is the world's first commercial capture, transportation, utilization and storage project of post-combustion $CO_2$ from a coal-fired thermo electric power plant, and the proposed storage is a saline aquifer at a depth of about 3,500 m. Deep saline aquifer, compared to hydrocarbon reservoir, provides the great volumetric potential for storage of $CO_2$ anywhere in the world, therefore the research results from the project may be exported globally to other sites. Geological $CO_2$ storage characterization for saline aquifer instead of hydrocarbon reservoir needs to estimate the geophysical properties of subsurface geology. This study calculated the geophysical property of water-saturated formation by applying amplitude variation analysis developed from oil and gas exploration. We correlated horizon tops at the well logs to seismic traveltime of 1,815 and 1,857 ms as Winnipeg and Deadwood formations. Gradient analysis from seismic traces showed correlation coefficient of 45 - 81 % on amplitude variation with respect to incident angle. Crossplot of intercept and gradient shows the inverse proportional trend which represents typical water saturated sediments. Product attribute of intercept and gradient described the base of wet sediment. Poisson's ratio change attribute increased at the top of target area satisfying with wet sediment and decreased at the top of basement in a dry rock bed.

Groundwater Flow Modeling in a Block-Scale Fractured Rocks considering the Fractured Zones (단열대의 영향을 고려한 블록 규모 단열 암반에서의 지하수 유동 모의)

  • Ko, Nak-Youl;Ji, Sung-Hoon;Koh, Yong-Kwon;Choi, Jon-Won
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.8 no.2
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    • pp.159-166
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    • 2010
  • The block-scale groundwater flow system at Olkiluoto site in Finland was simulated. The heterogeneous and anisotropic hydraulic conductivity field for the domain was constructed from the discrete fracture network, which considered only the fractured zones identified in the deep boreholes installed in the study site. The groundwater flow model was calibrated by adjusting the recharge rate and the transmissivities of the fractured zones to fit the calculated hydraulic heads and into- and out-flow rates in the observation intervals of the boreholes with the observed ones. In the calibrated model, the calculated flow rates at some intervals were not in accordance with the observed ones although the calculated hydraulic heads fit well with the observed ones, which revealed that the number of the conduits for groundwater flow is insufficient in the conceptual model for groundwater flow modeling. Therefore, it was recommended that the potential local conduits such as background fractures should be added to the present conceptual model.