• Korean Journal of Remote Sensing
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• v.18 no.2
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• pp.71-79
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• 2002

This research presents particulate distribution map of tidal flats of Hampyung bay using reflectance which extracted from satellite data and field survey data during same periods. The spectrum of particulate composition obtained from Landsat TM data was analysed and 7 scenes of satellite image were classified with ISODATA and K-MEANS methods. The results of unsupervised classification were estimated with in-situ data. The classification accuracy of ISODATA and K-MAMS methods were 84.3% and 85.7%. For validation of classified results of multi-temporal satellite images, TM image of May 1999(reference data), which was classified with field survey data was compared with classified results of multi-temporary satellite data.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.4
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• pp.405-411
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• 2011

In this study we tried to compare and analyze KOMPSAT-2 NOVI and vegetation coverage(VC) which is investigated by fieldwork. To standardize KOMPSAT-2 NOVI, we adjusted NOVI using reference data which is atmospheric corrected MODIS NDVI. Each vegetation coverage point data was surveyed in field using portable GPS and compared with NDVI of satellite imagery. As a results, there was high level of correlation in vegetation coverage and NOVI.

• Journal of Digital Convergence
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• v.17 no.7
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• pp.207-214
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• 2019

This study was designed to find effective CPR education methods by comparing and analyzing the quality of Field-Focus Type (FFT) CPR using SimPad and the quality of Video Self-lnstruction(VSI) CPR for the learners. The data collection were conducted from November 28, 2018 to December 5, 2018, on 64 first graders who completed CPR lectures at universities located in G metropolitan city, and analyzed using the SPSS ver. 23.0. The results of the study, Field Focus Type (FFT) CPR showed higher quality of Video Self-lnstruction (VSI) CPR in areas such as CPR total score, chest compressions score, chest compressions dept, chest compressions rate, chest compression velocity, total ventilation score, and Total number of ventilation than that of the subjects. Therefore, using Field Focus Type CPR (FFT) education law was found to improve the quality of cardiopulmonary resuscitation compared to the existing Video Self-lnstruction CPR (VSI) education method, and it is believed that it can be used as a basic data for cardiopulmonary resuscitation education in the future.

• Journal of Internet Computing and Services
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• v.25 no.2
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• pp.101-111
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• 2024

In this paper, we propose a concpetual architecture and its implementation approach for contextualizing unstructured CCTV-video frame data into structured XML-video textual data by using the deep-learning neural network models and frameworks. Conclusively, through the conceptual architecture and the implementation approach proposed in this paper, we can eventually realize and implement the so-called sharable working and experiencing knowledge management platforms to be adopted to smart factories in various industries.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1894-1897
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• 2009

최근 개발된 표면영상유속계(Surface Image Velocimetry)를 이용한 유량측정기법은 비교적 짧은 시간에 급변하는 홍수량을 정확도를 유지하면서도 간편하고 안전하게 측정할 수 있다는 장점이 있다. 그러나 표면영상유속계는 현장 상황과 사용 방법에 따라 측정된 유속값의 오차가 얼마나 발생하는지에 대한 근거가 없으며, 그 오차 범위가 명확하게 제시된 바가 없기 때문에 표면영상유속계의 신뢰성에 대해 의구심을 갖는 경우가 많다. 표면영상유속계의 유속측정 원리는 일정 시간간격을 갖는 두 영상내의 입자군 이동을 추적하여 유속벡터를 산정하는 것이다. 즉, 두 영상의 탐색 영역(searching area)내에서 각 입자군의 상관계수를 계산하여 최대상관계수를 갖는 입자군을 동일 입자군으로 판별하고, 동일 입자군의 도심간 거리와 두 영상의 시간간격을 이용하여 유속을 구하게 된다. 그러므로 상관계수가 높을수록 유속값이 정확하다고 할 수 있다. 따라서 본 연구에서는 상관계수에 따른 유속측정 오차를 분석하여 상관계수에 따른 표면영상유속계의 오차범위를 결정하고자 한다. 분석방법은 활차의 속도와 영상분석을 통해 얻은 속도를 비교하여 상관계수에 따른 오차범위를 살펴보았고, 실제 적용을 위하여 개수로내의 표면유속를 측정하여 상관계수에 따른 오차를 분석하였다. 분석 결과 상관계수가 0.7 이상인 측정유속의 정확도는 10% 이내로 확인되었으며, 향후 표면영상 유속계를 이용한 유속측정시 상관계수별 오차범위를 이용하여 현장적용시 정확도 개선을 위해 많은 도움이 될 것으로 기대된다.

• Tunnel and Underground Space
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• v.34 no.3
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• pp.208-217
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• 2024

There is so much research effort for developing and implementing deep learning-based surveillance systems to manage health and safety issues in construction sites. Especially, the development of deep learning-based object detection in various environmental changes has been progressing because those affect decreasing searching performance of the model. Among the various environmental variables, the accuracy of the object detection model is significantly dropped under low illuminance, and consistent object detection accuracy cannot be secured even the model is trained using low-light images. Accordingly, there is a need of low-light enhancement to keep the performance under low illuminance. Therefore, this paper conducts a comparative study of various deep learning-based low-light image enhancement models (GLADNet, KinD, LLFlow, Zero-DCE) using the acquired construction site image data. The low-light enhanced image was visually verified, and it was quantitatively analyzed by adopting image quality evaluation metrics such as PSNR, SSIM, Delta-E. As a result of the experiment, the low-light image enhancement performance of GLADNet showed excellent results in quantitative and qualitative evaluation, and it was analyzed to be suitable as a low-light image enhancement model. If the low-light image enhancement technique is applied as an image preprocessing to the deep learning-based object detection model in the future, it is expected to secure consistent object detection performance in a low-light environment.

• Journal of Environmental Impact Assessment
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• v.27 no.5
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• pp.475-488
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• 2018

Surveying urban tributary vegetation is based mainly on field sampling at present. The tributary vegetation survey integrating UAV NIR(Unmanned Aerial Vehicle Near Infrared Radiance) imagery and in-situ point photo has received only limited attentions from the field ecologist. The reason for this could be the largely undemonstrated applicability of UAV NIR imagery by the field ecologist as a monitoring tool for urban tributary vegetation. The principal advantage of UAV NIR imagery as a remote sensor is to provide, in a cost-effective manner, information required for a very narrow swath target such as urban tributary (10m width or so), utilizing very low altitude flight, real-time geo-referencing and stereo imaging. An exhaustive and realistic comparison of the two techniques was conducted, based on operational customer requirement of urban tributary vegetation survey: synoptic information, ground detail and quantitative data collection. UAV NIR imagery made it possible to identify area-wide patterns of the major plant communities subject to many different influences (e.g. artificial land use pattern), which cannot be acquired by traditional field sampling. Although field survey has already gained worldwide recognition by plant ecologists as a typical method of urban tributary vegetation monitoring, this approach did not provide a level of information that is either scientifically reliable or economically feasible in terms of urban tributary vegetation (e.g. remedial field works). It is anticipated that this research output could be used as a valuable reference for area-wide information obtained by UAV NIR imagery in urban tributary vegetation survey.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.520-524
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• 2010

본 연구에서는 팔당호에 유입되는 북한강, 남한강, 경안천의 6개 지류에 대하여 2009년 6월부터 12월까지 10일 주기로 현장 측정한 10개의 수질평가 항목과 측정시기에 근접한 4장의 시계열 위성영상에 의한 수질분석 기법을 이용하여 RS/GIS에 의한 수질환경 모니터링을 실시하였다. 현장에서는 다항목 수질측정기(DS5, Hydrolab ; 센서장착포트 7개, 측정항목 : 수온, 탁도, EC, LDO)를 이용하였고, 채수를 통해 실내에서 T-N, T-P, BOD, COD, ph, 부유물질(이하, SS)을 측정하였다. 위성영상에 의한 수질인자는 수온, 탁도, SS 등을 선정하여 자료의 정성적 해석을 통해 팔당호의 수질환경 모니터링을 수행하였다. 또한, 위성영상으로 분석한 수질평가 자료는 현장자료와의 상관성을 검토하였으며 회귀분석을 실시하여 수질인자별 분포도를 작성하였다.

• Journal of Korean Society for Geospatial Information Science
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• v.17 no.1
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• pp.105-111
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• 2009

A construction can be more convenient and safer with adequate informations. Consequently, studies on collecting various informations using newest surveying technology and applying these informations to a construction have been making progress recently. Digital images are easy to obtain and contain various informations. Therefore, with the recent development of image processing technology, the application field of digital images is getting wider. In this study, we proposed to use a fisheye lens camera in underground construction sites, especially tunnels, to overcome inconvenience in photographing with general lens cameras. A program for mapping the surface of a tunnel and making a mosaic image is also developed. This mosaic image can be applied to observe and analyze abnormal phenomenons on tunnel surface like cracks, water leakage, exfoliates, and so on.

• Explosives and Blasting
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• v.19 no.2
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• pp.5-18
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• 2001

채석, 광물채광 등의 발파에서 생성된 파쇄 암석편들에 대한 정확한 파쇄도의 측정은 발파효율성 및 경제성을 평가하기 위한 수단으로 사용될 수 있다. 발파현장에서 파쇄도의 측정은 파쇄암석의 크기를 대상으로 이루어지며, 이러한 측정의 궁극적인 목표는 파쇄도에 대한 정확한 측정과 분석을 통하여 발파를 최적화시킴으로써 과파쇄에 의한 화약의 낭비, 과대한 암괴로 인한 운반경비의 증가, 분할을 위한 2차 발파나 추가파쇄를 위한 경비증가 등을 줄일 수 있다. 또한 선광 및 파쇄장비들의 과대한 마모방지와 품질의 균질성 확보를 위한 모니터링의 수단으로 사용될 수도 있다. 최근 파쇄도측정에 많이 사용되고 있는 기술중의 하나가 영상처리 시스템으로, 본 논문에서는 촬영조건 및 분석대상물 등의 변화에 따른 이 영상처리기법의 문제에 대한 언급보다는 영상처리기법에 대한 이해를 돕기 위해 이 기법에 대한 설명과 상용 소프트웨어를 이용한 모델시험 및 채석현장에서 실시된 발파후의 파쇄암석들에 대한 파쇄도 분석에서의 문제점들에 대하여 언급하고자 한다.