• Korean Journal of Remote Sensing
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• v.37 no.3
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• pp.367-378
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• 2021

Field compost is a representative non-point pollution source for livestock. If the field compost flows into the water system due to rainfall, nutrients such as phosphorus and nitrogen contained in the field compost can adversely affect the water quality of the river. In this paper, we propose a method for detecting field compost using unmanned aerial vehicle images and deep learning-based semantic segmentation. Based on 39 ortho images acquired in the study area, about 30,000 data were obtained through data augmentation. Then, the accuracy was evaluated by applying the semantic segmentation algorithm developed based on U-net and the filtering technique of Open CV. As a result of the accuracy evaluation, the pixel accuracy was 99.97%, the precision was 83.80%, the recall rate was 60.95%, and the F1-Score was 70.57%. The low recall compared to precision is due to the underestimation of compost pixels when there is a small proportion of compost pixels at the edges of the image. After, It seems that accuracy can be improved by combining additional data sets with additional bands other than the RGB band.

• Korean Journal of Remote Sensing
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• v.29 no.4
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• pp.415-421
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• 2013

A new approach to retrieve the single-scattering albedo (SSA) of Asian dust plume, mixed with pollution particles, using multi-wavelength Raman lidar system was suggested in this study. Asian dust plume was separated as dust and non-dust particle (i.e. spherical particle) by the particle depolarization ratio at 532 nm. The vertical profiles of optical properties (the particle extinction coefficient at 355 and 532 nm and backscatter coefficient at 355, 532 and 1064 nm) for non-dust particle were used as input parameter for the inversion algorithm. The inversion algorithm provides the vertical distribution of microphysical properties of non-dust particle only so that the estimation of the SSA for the Asian dust in mixing state was suggested in this study. In order to estimate the SSA for the mixed Asian dust, we combined the SSA of non-dust particles retrieved by the inversion algorithms with assumed the SSA of 0.96 at 532 nm for dust. The retrieved SSA of Asian dust plume by lidar data was compared with the Aerosol Robotics Network (AERONET) retrieved values and showed good agreement.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1435-1447
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• 2020

The seasonal variations in weather parameters can significantly affect the atmospheric transmission characteristics. Herein, we propose a novel augmented multiple regression algorithm for the accurate estimation of atmospheric transmittance and solar irradiance over highly localized areas. The algorithm employs 1) adaptive atmospheric model selection using measured meteorological data and 2) multiple linear regression computation augmented with the conventional application of MODerate resolution atmospheric TRANsmission (MODTRAN). In this study, the proposed algorithm was employed to estimate the solar irradiance over Taean coastal area using the 2018 clear days' meteorological data of the area, and the results were compared with the measurement data. The difference between the measured and computed solar irradiance significantly improved from 89.27 ± 48.08σ W/㎡ (with standard MODTRAN) to 21.35 ± 16.54σ W/㎡ (with augmented multiple regression algorithm). The novel method proposed herein can be a useful tool for the accurate estimation of solar irradiance and atmospheric transmission characteristics of highly localized areas with various weather conditions; it can also be used to correct remotely sensed atmospheric data of such areas.

• Journal of Science of Art and Design
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• v.12
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• pp.145-191
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• 2007

21세기는 과학적 물질문명의 발달로 인하여, 과거에는 느껴보지 못했던 물질문명의 풍요를 이끌어 냈으며, 컴퓨터, 메스미디어의 발달로 인하여, 인간 문명의 관심은 지구계를 벗어나 우주론적으로 확장되어 마침내 우주시대를 열었다. 하지만 인간의 이성과 함께 영원하리라 믿었던 과학적 합리성은 20세기 초두에 제국주의적 전쟁을 일으키게 되었으며, 그로 말미암아 이성 파괴 현상이 드러나게 되었다. 급기야 20세기말에 이르러 다원주의라 칭하기도 하는 후기산업사회의 병적 증후군들, 국가간의 경제전쟁, 컴퓨터 및 각종 정보매체를 통한 신속한 정보교환의 이면에는 인간의 자기정체성의 혼돈을 아울러 초래하게 되었다. 과학기술의 발달로 생태계 및 환경은 오염되고 파괴되었다. 20세기말에는 산성비, 엘니뇨, 라니냐 현상으로 인하며, 환경의 재앙을 초래하면서 이제 인간은 문명에 대하여 여태껏 가져왔던 확고한 믿음에 회의를 갖게 된 것이다. 이와 같은 현상은 인간의 주체적 인식과 과학적 믿음의 지나친 숭배로 인하며 자연도 인간에 의하여 지배되고 인간을 위해서만 존재하는, 인간과 자연의 이원론적인 생각 즉, 인간의 이성에 의해서만 가능하다고 생각한 "근대적 주체"에 대한 맹신의 결과인 것이다. 이렇듯 20세기의 문제점은 21세기로 전가되어 여전히 계속되고 있으며, 세계내의 가장 큰 문제점은 전쟁, 기아 등 보다 이제는 오히려 환경. 생태문제로 귀결되어 지구의 생존권 자체가 위협을 받게 되었다. 미술도 서구문명의 근대주의적 영향에 의해서 모더니즘 등 이성위주의 미술인 "근대 주체적 미술"로 발전하였지만 포스터모더니즘에서 보여 지듯 이미 인간의 순수한 이성을 근간으로 한 미술에 있어서의 주체성 주장은 상당부분 무너졌으며, 이제는 장르의 해체와 다원화 현상으로 나아가게 되었다. 환경파괴에 직면하여 이제 주체는 자연이라는 타자를 새롭게 등장시킨다. 그리하여 생명중심주의, 전체론, 감각 중심주의 등 인간과 자연이 함께 공생하는 자연을 향한 생태적인 미술이 절실히 요구되는 것이다. 이에 본 연구논문은 무비판적 서구미술에 동요되지 않고, 지극히 자연적이고 동양적이기도 한 끊임없이 생명력을 창출해 내는 자연에 관심을 같게 되었으며, 환경의 중요성과 함께 생태학적 미술, 즉 생태미술에 본인의 작업을 관계시키고자 한다. 근대적 문명사에 의해 매장된 생태적 유기성의 흔적을 고고학적 탐사방법을 통하며 발굴해 내며, 환경윤리와 생태학, 심층 생태학, 북친의 '사회 생태학'을 수용하여 물질성의 생태적 복원과 함께 조형공간의 다원성에 대한 생태 미술의 일단을 규명코자 하였다.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1421-1434
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• 2020

The frequency and intensity of heatwaves have been increasing due to climate change. Since urban areas are more severely damaged by heatwaves as they act in combination with the urban heat island phenomenon, every possible preparation for such heat threats is required. Many overseas local governments build heat maps using a variety of spatial information to prepare for and counteract heatwaves, and prepare heatwave measures suitable for each region with different spatial characteristics within a relevant city. Building a heat map is a first and important step to prepare for heatwaves. The cases of heat map construction and thermal environment analysis involve various area distributions from urban units with a large area to local units with a small area. The method of constructing a heat map varies from a method utilizing remote sensing to a method using simulation, but there is no standard for using differentiated spatial information according to spatial scale, so each researcher constructs a heat map and analyzes the thermal environment based on different methods. For the above reason, spatial information standards required for building a heat map according to the analysis scale should be established. To this end, this study examined spatial information, analysis methodology, and final findings related to Korean and oversea analysis studies of heatwaves and urban thermal environments to suggest ways to improve the utilization efficiency of spatial information used to build urban heat maps. As a result of the analysis, it was found that spatial, temporal, and spectral resolutions, as basic resolutions, are necessary to construct a heat map using remote sensing in the use of spatial information. In the use of simulations, it was found that the type of weather data and spatial resolution, which are input condition information for simulation implementation, differ according to the size of analysis target areas. Therefore, when constructing a heat map using remote sensing, spatial, spectral, and temporal resolution should be considered; and in the case of using simulations, the spatial resolution, which is an input condition for simulation implementation, and the conditions of weather information to be inputted, should be considered in advance. As a result of understanding the types of monitoring elements for heatwave analysis, 19 types of elements were identified such as land cover, urban spatial characteristics, buildings, topography, vegetation, and shadows, and it was found that there are differences in the types of the elements by spatial scale. This study is expected to help give direction to relevant studies in terms of the use of spatial information suitable for the size of target areas, and setting monitoring elements, when analyzing heatwaves.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.62-65
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• 2006

가스하이드레이트의 국내 부존 가능성이 확인됨에 따라 가스하이드레이트 개발기술 및 부존 정보의 확보를 위한 가스하이드레이트 연구개발사업이 추진 중에 있다. 가스하이드레이트 개발사업과 같은 국가주도 연구개발사업의 경우 사업의 타당성 확보와 효율적인 추진을 위해서 사업 및 개발기술의 가치를 객관적으로 평가해야 할 필요성이 높아지고 있다. 본 연구에서는 가스하이드레이트 개발사업의 가치평가를 위한 주요 속성들을 결정하고 속성별 쌍대비교를 통해 중요도를 도출 할 수 있는 Fuzzy AHP 방법론을 사용하여 상대적 가중치를 도출하였다 연구 결과 가스하이드레이트 개발사업 및 기술의 가치는 상위계층으로 직접가치와 유발가치로 나눌 수 있고, 하위계층으로 총 8개의 속성으로 분류 할 수 있는 것으로 분석되었다. 중요도 분석결과 가스하이드레이트를 직접 개발함으로써 얻을 수 있는 개발가치가 사업시행으로 인한 탐사개발 기술의 확보로 유발되는 가치보다 높은 중요도를 가지는 것으로 평가 되었다. 또한 개발가치의 세부항목 중에는 에너지 안보 증진 효과가, 유발가치의 세부항목 중에는 인력양성효과가 가장 중요한 가치평가 요소로 나타났다

• Journal of the Korean Society for Library and Information Science
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• v.37 no.2
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• pp.153-168
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• 2003

A hyperlink on academic World Wide Web has started to be recognized as a form of collaborative communication network connecting individual researchers and research groups and expanding their collaboration relations by making possible easy and direct online contact among people or groups anywhere in the world. This paper describes the structure of academic hyperlinks embedded in universities' Web sites hosted at the 10 Asian countries and further, examines the association between the structure of the hyperlink network and collaborative communication pattern among those countries based on their frequency of co-authoring articles. This research found that the number of inter-hyperlinks among universities' Web sites was significantly correlated with the frequency of co-authored articles across the 10 countries.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.7-17
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• 2005

The determination of seismic velocities in refractors for near-surface seismic refraction investigations is an ill-posed problem. Small variations in the computed time parameters can result in quite large lateral variations in the derived velocities, which are often artefacts of the inversion algorithms. Such artefacts are usually not recognized or corrected with forward modelling. Therefore, if detailed refractor models are sought with model based inversion, then detailed starting models are required. The usual source of artefacts in seismic velocities is irregular refractors. Under most circumstances, the variable migration of the generalized reciprocal method (GRM) is able to accommodate irregular interfaces and generate detailed starting models of the refractor. However, where the very-near-surface environment of the Earth is also irregular, the efficacy of the GRM is reduced, and weathering corrections can be necessary. Standard methods for correcting for surface irregularities are usually not practical where the very-near-surface irregularities are of limited lateral extent. In such circumstances, the GRM smoothing statics method (SSM) is a simple and robust approach, which can facilitate more-accurate estimates of refractor velocities. The GRM SSM generates a smoothing 'statics' correction by subtracting an average of the time-depths computed with a range of XY values from the time-depths computed with a zero XY value (where the XY value is the separation between the receivers used to compute the time-depth). The time-depths to the deeper target refractors do not vary greatly with varying XY values, and therefore an average is much the same as the optimum value. However, the time-depths for the very-near-surface irregularities migrate laterally with increasing XY values and they are substantially reduced with the averaging process. As a result, the time-depth profile averaged over a range of XY values is effectively corrected for the near-surface irregularities. In addition, the time-depths computed with a Bero XY value are the sum of both the near-surface effects and the time-depths to the target refractor. Therefore, their subtraction generates an approximate 'statics' correction, which in turn, is subtracted from the traveltimes The GRM SSM is essentially a smoothing procedure, rather than a deterministic weathering correction approach, and it is most effective with near-surface irregularities of quite limited lateral extent. Model and case studies demonstrate that the GRM SSM substantially improves the reliability in determining detailed seismic velocities in irregular refractors.

• Korean Journal of Remote Sensing
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• v.33 no.6_2
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• pp.1041-1046
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• 2017

The Ministry of Environment(ME) has been producing and providing various environmental spatial information including land-cover maps in order to effectively cope with environmental issues. With the advent of the 4th industrial revolution era and the frequent occurrence of environmental disasters, the necessity of combining the environmental spatial information with the newest technology is increasing. By considering the increased necessity, the ME and the Korean Society of Remote Sensing held the 2017 Environmental Spatial Information Research Paper Competition with the aim of both discovering new application fields of environmental spatial information and supporting outstanding researchers. The outstanding 9 papers were finally selected after reviewing 51 papers submitted for the competition. This special issue includes the 9 papers that address advanced methodologies and application results based on environmental spatial information, as well as recent environmental issues. We expect the methodologies and applications presented in this special issue would be a reference anthology for users of environmental spatial information.

• Journal of the Korean Geophysical Society
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• v.7 no.4
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• pp.313-324
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• 2004

The finite element method and statistics of the convergence measurement are useful method of the stability analysis of the tunnel adjacent to the pier. It is the purpose of the this case study to certificate of validity of the application of those methods. The safety of the pilot tunnel method and LW pre-grouting has been evaluated from the FEM analysis. The three-dimensional finite element method is carried out for the decision of the level of stress redistribution at the two-dimensional numerical analysis. An analysis of the convergence is carried out by the estimation of preceding convergence at tunnel excavation. F-examination is applied for this estimation. As results of that analysis, The F-value is from 10.81 to 158.74 and the coefficient of determination is from 0.82 to 0.99. An analysis of convergence is carried out by using regression analysis. Consequently, it is shown that the convergence can be modeled as following function C(t) = a[1-exp(-bt)].