• Title/Summary/Keyword: High resolution studies

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A Basic Study on Micro-Electric Potential accompanied with Specimen Failure during Uniaxial Compressive Test (일축 압축에 의한 시료 파괴 시 수반되는 미소 전위에 대한 기초 연구)

  • Kim, Jong-Wook;Park, Sam-Gyu;Song, Young-Soo;Sung, Nak-Hun;Kim, Jung-Ho;Cho, Seong-Jun
    • Geophysics and Geophysical Exploration
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    • v.10 no.3
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    • pp.203-210
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    • 2007
  • As a part of basic studies on monitoring of landslides and slope stability using SP measurements, micro-electric potentials of rock samples were measured accompanied with the rock failure by a uniaxial loading test were measured. The measurement system consists of a 8 channel A/D converter with 24 bit resolution, uniaxial loading tester, strain gages and 4 sets of electrode attached to a rock sample. Rock samples of granite, limestone, and sandstone were tested. Also, mortar samples were tested in order to monitor electric-potentials of a uniform sample. Micro-electric potentials were detected in all saturated samples and the strength of them increased as the loading force increased. Sandstone samples showed the largest strength of micro-electric potential and it followed limestone and granite samples, which indicates a positive relationship with porosity of rocks. The mechanism generating these micro-electric potential can be explained in terms of electro-kinetics. In case of dry samples, micro-electric potential could be observed only in sandstone samples, where piezoelectric effect played main role due to high contents of quartz in sandstone samples. We found that biggest micro-electric potentials were observed at the electrodes near the crack surface of rock samples. This is very encouraging result that SP monitoring can be applied to predicting landsliding or to estimate collapsing position combining with monitoring of acoustic emissions.

Implementation of GLCM/GLDV-based Texture Algorithm and Its Application to High Resolution Imagery Analysis (GLCM/GLDV 기반 Texture 알고리즘 구현과 고 해상도 영상분석 적용)

  • Lee Kiwon;Jeon So-Hee;Kwon Byung-Doo
    • Korean Journal of Remote Sensing
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    • v.21 no.2
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    • pp.121-133
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    • 2005
  • Texture imaging, which means texture image creation by co-occurrence relation, has been known as one of the useful image analysis methodologies. For this purpose, most commercial remote sensing software provides texture analysis function named GLCM (Grey Level Co-occurrence Matrix). In this study, texture-imaging program based on GLCM algorithm is newly implemented. As well, texture imaging modules for GLDV (Grey Level Difference Vector) are contained in this program. As for GLCM/GLDV Texture imaging parameters, it composed of six types of second order texture functions such as Homogeneity, Dissimilarity, Energy, Entropy, Angular Second Moment, and Contrast. As for co-occurrence directionality in GLCM/GLDV, two direction modes such as Omni-mode and Circular mode newly implemented in this program are provided with basic eight-direction mode. Omni-mode is to compute all direction to avoid directionality complexity in the practical level, and circular direction is to compute texture parameters by circular direction surrounding a target pixel in a kernel. At the second phase of this study, some case studies with artificial image and actual satellite imagery are carried out to analyze texture images in different parameters and modes by correlation matrix analysis. It is concluded that selection of texture parameters and modes is the critical issues in an application based on texture image fusion.

A Study of the Narrative Structure and the Writer's Intent in the Hasaenggiwoojun(何生奇遇傳) (<하생기우전>의 서사구조와 작가적 의미 - 갈등양상을 중심으로 -)

  • Moon, Beom-doo
    • Journal of Korean Classical Literature and Education
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    • no.37
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    • pp.111-149
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    • 2018
  • This story is written by Shin Kwang-han who is a famous scholar and writer in Josun Dynasty. The most notable feature of this story is the love between a man and a dead woman. The protagonist has failed the test to be a national official for several years, because of the corruption and unfairness of the leaders of his society. He is very upset, but then changes his mind in order to become an officer. One day he meets a dead woman. He saves her life from death, and falls in love with her. Finally he marries her and attains a high position. Till now, all the aspects of this story have been extensively researched from a number of different perspectives. However the narrative structure of this story has not been discussed much. This story belongs to Jungi-novel, a kind of old story style which includes fantasy. The studies on this story have mostly been carried out to find the different features in comparison with other works of the same style. Further, we could not understand its own specific meaning structure. This study aims to find the narrative structure of this story. It was recognized by researchers that Shin's stories talk about his life and his perspective of the world. Further, I will try to show how he expresses his thoughts, emotion and life through this story. First, to obtain a satisfactory result through this study, I will find a way to resolve several problems that have become the center of the controversy. Afterward, the conflict and resolution the hero's relation to the world will be identified in every paragraph. Through these efforts, we will have a new point of the view about the narrative structure of this story and the intent expressed by the writer through its structure.

SOC Project Plans and Cultural Resource Management in the North Korean Region : Suggestions for Systematic Investigation and Management of North Korean Cultural Heritage (북한지역 SOC사업 구상과 문화유산 - 북한 문화유산의 효율적인 조사·관리를 위한 제언 -)

  • Kim, Beom-Cheol
    • Korean Journal of Heritage: History & Science
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    • v.52 no.2
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    • pp.4-19
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    • 2019
  • Despite continuous volatility in ideological leanings, South Korean governments, conservative or progressive, have published a series of plans for aiding the economic development of North Korea. The Moon administration's plan is the paragon of such efforts. In addition, recent detente between the North Korean regime and the US government evokes much hope in its success. There is, hidden behind the veil of hope, apprehension about the crisis of management of cultural heritage in the North Korean region. It is believed that development policies may overwhelm efforts at conservation of cultural heritage, in particular that the hurrying of development projects would provoke insufficient and inappropriate investigation of archaeological sites., If these problems arise, responsibility for their resolution would be carried by South Korean archaeologists and governmental institutes. This paper reviews what the South Korean government has suggested for North Korea's economic recovery and examines what capability the South Korean archaeology sector has for investigating North Korean cultural heritage. It then discusses the scale of investigation needed, and what should beused as precedent in planning substantial excavations when development projects are performed in the North Korean region. Constructing a digital map system for cultural heritage of North Korea is suggested as one of the most urgent tasks precedent to substantial excavations. It is of great importance because we do not currently have any substantial information about the locations and current condition of cultural heritage sites and artifacts in the North Korean region. The mapping of Bronze Age sites in North Korea, conducted as a sort of pilot test, revealed that archaeological sites are densely distributed in several regions, especially Hwanghae-do and Pyoyang Directly-Administrated City, and that there is high potential of discovering new sites.

Evaluation of Grid-Based ROI Extraction Method Using a Seamless Digital Map (연속수치지형도를 활용한 격자기준 관심 지역 추출기법의 평가)

  • Jeong, Jong-Chul
    • Journal of Cadastre & Land InformatiX
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    • v.49 no.1
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    • pp.103-112
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    • 2019
  • Extraction of region of interest for satellite image classification is one of the important techniques for efficient management of the national land space. However, recent studies on satellite image classification often depend on the information of the selected image in selecting the region of interest. This study propose an effective method of selecting the area of interest using the continuous digital topographic map constructed from high resolution images. The spatial information used in this research is based on the digital topographic map from 2013 to 2017 provided by the National Geographical Information Institute and the 2015 Sejong City land cover map provided by the Ministry of Environment. To verify the accuracy of the extracted area of interest, KOMPSAT-3A satellite images were used which taken on October 28, 2018 and July 7, 2018. The baseline samples for 2015 were extracted using the unchanged area of the continuous digital topographic map for 2013-2015 and the land cover map for 2015, and also extracted the baseline samples in 2018 using the unchanged area of the continuous digital topographic map for 2015-2017 and the land cover map for 2015. The redundant areas that occurred when merging continuous digital topographic maps and land cover maps were removed to prevent confusion of data. Finally, the checkpoints are generated within the region of interest, and the accuracy of the region of interest extracted from the K3A satellite images and the error matrix in 2015 and 2018 is shown, and the accuracy is approximately 93% and 72%, respectively. The accuracy of the region of interest can be used as a region of interest, and the misclassified region can be used as a reference for change detection.

Effects of Korean Medicine in Idiopathic Pulmonary Fibrosis Patients - A Retrospective Chart Review (한방병원에 내원한 특발성 폐섬유화증 환자 82명에 대한 임상적 특징 분석; 후향적 차트 리뷰)

  • Hong, Sung-eun;Kang, Sung-woo;Park, Ji-won;Jang, Kwon-jun;Park, Su-hyeon;Kim, Kwan-il;Bu, Yung-min;Jung, Hee-jae;Lee, Beom-joon
    • The Journal of Internal Korean Medicine
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    • v.42 no.3
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    • pp.375-384
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    • 2021
  • Objective: This study was designed to analyze the clinical features of idiopathic pulmonary fibrosis patients who attended a Korean medicine hospital and the treatment effects through retrospective chart reviews. Methods: The medical records of 82 outpatients who had been diagnosed with idiopathic pulmonary fibrosis and visited the Allergy, Immune, and Respiratory System Department of Kyung Hee Korean Medicine Hospital from 8 January 2015 to 8 January 2021 were retrospectively reviewed. To assess the treatment outcomes, we used the FVC (Forced Vital Capacity), DLCO (Diffusing capacity of the Lung for CO), 6-minute walk test, and HRCT (High Resolution Computed Tomography). Results: The study group consisted of 28 females and 54 males. The median age of the patients was 67.98±11.44 years. The chief complaints were cough (n=51) and dyspnea (n=49). Other frequent symptoms were general weakness (n=8), weight loss (n=4), and a fever (n=2). A total of 77 (93.90%) patients were prescribed Korean herbal medicine, and 52 (63.41%) patients were treated with acupuncture, moxibustion, cupping therapy, ICT, or pharmacopuncture. After treatments, FVC, DLCO, the 6-minute walk test, and HRCT were maintained or worsened slightly. Conclusions: This study presented the characteristics of idiopathic pulmonary fibrosis patients treated by Korean medical therapies, and further studies of Korean medical treatments for idiopathic pulmonary fibrosis patients would be valuable.

Reconfiguration of Physical Structure of Vegetation by Voxelization Based on 3D Point Clouds (3차원 포인트 클라우드 기반 복셀화에 의한 식생의 물리적 구조 재구현)

  • Ahn, Myeonghui;Jang, Eun-kyung;Bae, Inhyeok;Ji, Un
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.40 no.6
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    • pp.571-581
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    • 2020
  • Vegetation affects water level change and flow resistance in rivers and impacts waterway ecosystems as a whole. Therefore, it is important to have accurate information about the species, shape, and size of any river vegetation. However, it is not easy to collect full vegetation data on-site, so recent studies have attempted to obtain large amounts of vegetation data using terrestrial laser scanning (TLS). Also, due to the complex shape of vegetation, it is not easy to obtain accurate information about the canopy area, and there are limitations due to a complex range of variables. Therefore, the physical structure of vegetation was analyzed in this study by reconfiguring high-resolution point cloud data collected through 3-dimensional terrestrial laser scanning (3D TLS) in a voxel. Each physical structure was analyzed under three different conditions: a simple vegetation formation without leaves, a complete formation with leaves, and a patch-scale vegetation formation. In the raw data, the outlier and unnecessary data were filtered and removed by Statistical Outlier Removal (SOR), resulting in 17%, 26%, and 25% of data being removed, respectively. Also, vegetation volume by voxel size was reconfigured from post-processed point clouds and compared with vegetation volume; the analysis showed that the margin of error was 8%, 25%, and 63% for each condition, respectively. The larger the size of the target sample, the larger the error. The vegetation surface looked visually similar when resizing the voxel; however, the volume of the entire vegetation was susceptible to error.

A Study on Traditional Darangyi-Rice Terrace as Design Factors of Agricultural Landscape (농업경관의 디자인적 요소인 전통다랑논 조사연구)

  • Son, Ho-Gi;Kim, Sang-Bum;Kim, Eun-Ja;Rhee, Sang-Young
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.1
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    • pp.157-165
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    • 2011
  • This study is to be used as a fundamental material of rural amenity resources researches, such as excavating, establishing and modifying national agricultural landscape resources, so as to efficiently manage them. It is carried out with targeting traditional Darangyi-Rice terrace which has design factors of agricultural landscape resources. We have set up the standard range with practicable similar standard(Marginal Farmland and Less Favored Areas and etc), those of Japan, and the results of analyzing the characteristics of Darangyi-Rice terrace already known. As a result of the field investigation, it has been revealed that a great deal of Darangyi-Rice terrace are being used for not corresponding purposes, or damaged and disappeared. For preserving and well-managing Darangyi-Rice terrace as a rural landscape resource which has rural design factors, it should be advanced detailed and accurate studies on present conditions and changes of Darangyi-Rice terrace, with researches on significances, values, utilities and economical efficiency of Darangyi-Rice terrace by regions. In addition, we utilized various spatial imagery data in the researching process. Consequently, it is concluded that if high resolution imagery data is used, it can establish rather minute and accurate large-scale DB, and monitor elaborate changes as well. It is therefore thought that its application can be higher as actualizing DB hereafter.

Changes in the Spatiotemporal Patterns of Precipitation Due to Climate Change (기후변화에 따른 강수량의 시공간적 발생 패턴의 변화 분석)

  • Kim, Dae-Jun;Kang, DaeGyoon;Park, Joo-Hyeon;Kim, Jin-Hee;Kim, Yongseok
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.4
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    • pp.424-433
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    • 2021
  • Recent climate change has caused abnormal weather phenomena all over the world and a lot of damage in many fields of society. Particularly, a lot of recent damages were due to extreme precipitation, such as torrential downpour or drought. The objective of this study was to analyze the temporal and spatial changes in the precipitation pattern in South Korea. To achieve this objective, this study selected some of the precipitation indices suggested in previous studies to compare the temporal characteristics of precipitation induced by climate change. This study selected ten ASOS observatories of the Korea Meteorological Administration to understand the change over time for each location with considering regional distribution. This study also collected daily cumulative precipitation from 1951 to 2020 for each point. Additionally, this study generated high-resolution national daily precipitation distribution maps using an orographic precipitation model from 1981 to 2020 and analyzed them. Temporal analysis showed that although annual cumulative precipitation revealed an increasing trend from the past to the present. The number of precipitation days showed a decreasing trend at most observation points, but the number of torrential downpour days revealed an increasing trend. Spatially, the number of precipitation days and the number of torrential downpour days decreased in many areas over time, and this pattern was prominent in the central region. The precipitation pattern of South Korea can be summarized as the fewer precipitation days and larger daily precipitation over time.

Spatial Gap-filling of GK-2A/AMI Hourly AOD Products Using Meteorological Data and Machine Learning (기상모델자료와 기계학습을 이용한 GK-2A/AMI Hourly AOD 산출물의 결측화소 복원)

  • Youn, Youjeong;Kang, Jonggu;Kim, Geunah;Park, Ganghyun;Choi, Soyeon;Lee, Yangwon
    • Korean Journal of Remote Sensing
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    • v.38 no.5_3
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    • pp.953-966
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    • 2022
  • Since aerosols adversely affect human health, such as deteriorating air quality, quantitative observation of the distribution and characteristics of aerosols is essential. Recently, satellite-based Aerosol Optical Depth (AOD) data is used in various studies as periodic and quantitative information acquisition means on the global scale, but optical sensor-based satellite AOD images are missing in some areas with cloud conditions. In this study, we produced gap-free GeoKompsat 2A (GK-2A) Advanced Meteorological Imager (AMI) AOD hourly images after generating a Random Forest based gap-filling model using grid meteorological and geographic elements as input variables. The accuracy of the model is Mean Bias Error (MBE) of -0.002 and Root Mean Square Error (RMSE) of 0.145, which is higher than the target accuracy of the original data and considering that the target object is an atmospheric variable with Correlation Coefficient (CC) of 0.714, it is a model with sufficient explanatory power. The high temporal resolution of geostationary satellites is suitable for diurnal variation observation and is an important model for other research such as input for atmospheric correction, estimation of ground PM, analysis of small fires or pollutants.