• Structural Engineering and Mechanics
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• v.67 no.2
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• pp.105-113
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• 2018

To improve the prediction accuracy of the strong-unloading rock slope performance and obtain the range of variation in the slope displacement, a new displacement time-series prediction model is proposed, called the fuzzy information granulation (FIG)-genetic algorithm (GA)-back propagation neural network (BPNN) model. Initially, a displacement time series is selected as the training samples of the prediction model on the basis of an analysis of the causes of the change in the slope behavior. Then, FIG is executed to partition the series and obtain the characteristic parameters of every partition. Furthermore, the later characteristic parameters are predicted by inputting the earlier characteristic parameters into the GA-BPNN model, where a GA is used to optimize the initial weights and thresholds of the BPNN; in the process, the numbers of input layer nodes, hidden layer nodes, and output layer nodes are determined by a trial method. Finally, the prediction model is evaluated by comparing the measured and predicted values. The model is applied to predict the displacement time series of a strong-unloading rock slope in a hydropower station. The engineering case shows that the FIG-GA-BPNN model can obtain more accurate predicted results and has high engineering application value.

• Korean Journal of Family Social Work
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• no.62
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• pp.141-169
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• 2018

This study was a qualitative case study of mother's experiences chidult in South Korea focusing on North Korean single mom defector with children in their 20s. The purpose of the present study was to explores the mother's experiences of North Korean single mom defector without their spouses. Semi-structured in-depth interviews were arranged with 3 North Korean refugee mothers without their spouses who met the criteria for the present research purpose. As a result of the analysis, the mother's experiences into five main clusters of themes which may be labeled as (1) The presence of more meaningful children in a strange land, (2) Everyday life, such as the superwoman, (3) The rigor of a care to too cumbersome, (4) Gratitude and value discovery in our daily lives, (5) To find new life. In all there are ten sub categories to consider. On the basis of these results, we presented some conclusions on the mother's experiences of North Korean single mom defector. We also presented some implications of these results on welfare services and future research.

• Korean Journal of Remote Sensing
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• v.23 no.2
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• pp.89-101
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• 2007

This paper investigates the effects of the fusion of multifrequency (C and L bands) polarimetric SAR data in land-cover classification. NASA JPL AIRSAR C and L bands data were used to supervised classification in an agricultural area to simulate the integration of ALOS PALSAR and Radarsat-2 SAR data to be available. Several scattering features derived from target decomposition based on eigen value/vector analysis were used as input for a support vector machines classifier and then the posteriori probabilities for each frequency SAR data were integrated by applying a probabilistic ratio model as a decision level fusion methodology. From the case study results, L band data had the proper amount of penetration power and showed better classification accuracy improvement (about 22%) over C band data which did not have enough penetration. When all frequency data were fused for the classification, a significant improvement of about 10% in overall classification accuracy was achieved thanks to an increase of discrimination capability for each class, compared with the case of L band Shh data.

• Korean Journal of Remote Sensing
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• v.26 no.4
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• pp.403-410
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• 2010

NDVI(Normalized Difference Vegetation Index), which is broadly used as short-term data composite, is an important parameter for climate change and long-term land surface monitoring. Although atmospheric correction is performed, NDVI dramatically appears several low peak noise in the long-term time series. They are related to various contaminated sources, such as cloud masking problem and wet ground condition. This study suggests a simple method through harmonic analysis for reducing NDVI noise using SPOT/VGT NDVI 10-day MVC data. The harmonic analysis method is compared with the polynomial regression method suggested previously. The polynomial regression method overestimates the NDVI values in the time series. The proposed method showed an improvement in NDVI correction of low peak and overestimation.

• Journal of Korea Water Resources Association
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• v.52 no.10
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• pp.707-718
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• 2019

The optimal water allocation pursues a reliable and economic supply of water resources to meet various interests in socio-economic-environmental aspects. The global water shortage has intensified due to climate change and population growth with limited water resources. Thus, the water management scheme has shifted to improve water use efficiency by proper demand management and water allocation planning. Here, a hydro-economic water allocation model, called WAMM (Water Allocation and Management Model) is introduced. The WAMM is equipped with an improved linear programming algorithm for optimal water allocation and estimates economic value of water supply as an objective of water

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.102-102
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• 2015

최근 중소규모 하천은 하천수 및 하천변 지하수 이용의 증가와 토지이용변화 등 유역 내 수문인자의 특성 변화로 인해 하천의 건천화가 점증하고 있어 하천 환경이 악화되고 있는 실정이다. 본 연구에서는 격자기반의 분포형 장기수문 모델(PGA-CC)을 이용하여 과거 수십년동안 토지이용변화에 따른 하천 건천화 영향을 평가하였다. 실제 건천화가 진행되고 있는 삽교천 상류유역($358.8km^2$)을 선정하였고 토지이용변화분석을 위해 과거 1975년 토지이용도(Past), 현재 2008년 토지이용도(Present)를 구축하였다. 각각의 토지이용 항목 중 변화율이 가장 높은 도시비율은 과거 토지이용도에서는 2.6 %였으며 현재 토지이용도에서는 11.3 %로 8.7 %가 증가하였다. 모델 검보정은 최근 7년(2005-2011)동안 최종유역출구지점에서 유출 검보정을 실시하였다. 그 결과 NSE (Nash-Sutcliffe model efficiency)은 평균 0.71로 유출량의 모의값과 실측값이 유효한 것으로 나타났다. 건천화를 평가하기 위해 시험유역에서의 5 WPs (Watching Points)를 선정하여 과거 및 현재 토지이용조건을 모의하고 유황분석을 통한 갈수 변화량 분석을 실시하였다. 건천화 빈도분석을 위해 GEV (Generalized Extreme Value) 갈수빈도분석을 실시하여 과거 토지이용 모의결과 산정된 평균 갈수량($m^3/s$) 이하로 낮아지는 유출량 일수를 계산하였다. 최종유역출구에서 과거 및 현재 토지이용도에서 모의된 평균갈수량은 각각 $3.27m^3/s$ 및 $3.11m^3/s$로 나타났다. GEV 갈수빈도분석결과 과거 토지이용조건에서의 평균갈수량은 $3.20m^3/s$(재현기간 2.33년)으로 나타났다. 도시증가에 따른 인구증가는 지하수 사용량에 증가를 가져온다. 이는, 건천화에 영향을 미치며 본 연구에서는 지하수이용량 자료(1998-2011)를 이용하여 도시면적과 지하수이용량의 선형회귀분석을 실시하여 과거 22년 지하수 사용량을 예측하였다. 그 결과 지하수사용량 증가는 토지이용변화와 복합적으로 상류유역에 하천의 변화를 가속시키는 것으로 나타냈다.

• Journal of the Korea Institute of Construction Safety
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• v.1 no.1
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• pp.16-21
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• 2018

The purpose of this study was to utilize 90 construction site accidents accumulated from 15 years ago by the Office of the High Level Investigation Committee of the Korea Infrastructure Safety Corporation under consignment from the Ministry of Land, Infrastructure and Transport. The construction site accident population used in this study is difficult to represent the entire construction site accident, but is considered to have statistical value as analysis data for a given size of construction site accident. The analysis is believed to be available on site as a basic data for securing construction safety and is expected to be used as a data for establishing future direction of construction safety policy.

• Journal of Forest and Environmental Science
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• v.27 no.2
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• pp.81-91
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• 2011

An exploratory study was conducted in Gopalganj, a southern district of Bangladesh to explore the role of wild date palm (Phoenix sylvestris Roxb.) husbandry in the rural economy. A total of 36 households in the study area were interviewed using a semi-structured questionnaire. A multistage sampling method with 10% intensity and a semi-structured questionnaire were used for the study. Based on the land holding capacity of the households, the farmers were categorized into five groups as landless, marginal, small, medium, and large. The date palm was distributed over seven different habitats of which roadside support the highest value (31%) followed by agricultural field and orchard (25% each). Though the large category farmers own most of the palms (43%), a considerable portion (562 individuals out of 1980) of it is managed by the landless farmers, who earn a substantial livelihood from the palms. The farmers manage the palm mainly for juice production; juice is either used fresh as drink or after some sort of processing as molasses and/or alcoholic beverage. Date palm husbandry contributes 32,601 Tk., 21,107 Tk., 20,626 Tk., 29,574 Tk. and 35,335 Tk. respectively to the five group seasonally and 50,980 Tk., 77,556 Tk., 90,208 Tk., 112,560 Tk., 140,675 Tk. respectively annually (1 US$ = 70 Tk.). Date palm trees contribute 65.48% of mean annual income to landless farmers followed by 27.21% to marginal farmers. However the poor marketing system result in decreasing the annual return from palm trees. Palm husbandry could be a promising source of rural incomes in Bangladesh if the farmers' traditional management knowledge was linked to more scientific management practices.

• Korean Journal of Remote Sensing
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• v.37 no.5_1
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• pp.1071-1081
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• 2021

Remote Sensing using unmanned aerial vehicles(UAV) can acquire images with higher time resolution and spatial resolution than aerial and satellite remote sensing. However, UAV images are photographed at low altitude and the area covered by one image isrelatively narrow. Therefore multiple images must be processed to monitor large area. Since UAV images are photographed under different exposure conditions, there is difference in brightness values between adjacent images. When images are mosaicked, unnatural seamlines are generated because of the brightness difference. Therefore, in order to generate seamless mosaic image, a radiometric processing for correcting difference in brightness value between images is essential. This paper proposes a relative radiometric calibration and image blending technique. In order to analyze performance of the proposed method, mosaic images of UAV images in agricultural and mountainous areas were generated. As a result, mosaic images with mean brightness difference of 5 and root mean square difference of 7 were avchieved.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2014.05a
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• pp.844-847
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• 2014

'Healthcare 3.0' paradigm, which comes from the convergence of medical and department of ICT(Information and Communication Technology), meets the government's 'creative economy'. It has emerged as new higher value-added markets and industries, created jobs, and got the 'land of opportunity'. Despite of the global recession, the health care market in the world from 2009 to now has earned a steady growth. The annual growth rate in domestic industrial scale is expected to more than 10% higher based on 153 trillion won in 2010. In particular, combination of health care and ICT, BT(BioTechnology), NT(NanoTtechnology), which is so called 'super-convergence', leap in the health care industry, is expected to open up a new paradigm. In addition, by 2020 all of the health care industry, the IT convergence industries account for the largest proportion, and more than 50,000 of the employment are to be expected. In this study, we survey and analyze problems of medical and IT convergence technology, the future of the medical and health care industry, the demanded healthcare IT staff, finally suggest education plan of human resources required in convergence industry of medical and IT.