• Geophysics and Geophysical Exploration
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• v.6 no.1
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• pp.7-12
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• 2003

The lineament extraction from satellite images is important in the geologic studies including groundwater and mineral exploration, groundwater survey, natural hazard analysis, and many others. The lineaments in remote sensing images are identified by the difference of pixel values or brightness. Since the visual interpretation is apt to be influenced by the knowledges and experiences, many of the automatic lineament detection algorithms are developed to ensure the objectives and efficient outputs. DSTA (dynamic segment tracing algorithm) is one of such algorithms, which can be applied to not only mountainous area but also alluvial area. However, when the alluvial area is wider than mountain region, somewhat severe noises are generated. To reduce such noises, AERA (alluvial effect reducing algorithm) is proposed and tested for the image which contains mountains, cultivated land and urban area. Upon the application of AERA, alluvial effects in lineament extraction from satellite image are substantially reduced.

• Korean Journal of Remote Sensing
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• v.14 no.2
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• pp.175-195
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• 1998

Automatic lineament extraction algorithms had been developed by various researches for geological purpose using remotely sensed data. However, most of them are designed for a certain topographic model, for instance rugged mountainous region or flat basin. Most of common topographic characteristic in Korea is a mountainous region along with alluvial plain, and consequently it is difficult to apply previous algorithms directly to this area. A new algorithm of automatic lineament extraction from remotely sensed images is developed in this study specifically for geological applications. An algorithm, named as DSTA(Dynamic Segment Tracing Algorithm), is developed to produce binary image composed of linear component and non-linear component. The proposed algorithm effectively reduces the look direction bias associated with sun's azimuth angle and the noise in the low contrast region by utilizing a dynamic sub window. This algorithm can successfully accomodate lineaments in the alluvial plain as well as mountainous region. Two additional algorithms for estimating the individual lineament vector, named as ALEHHT(Automatic Lineament Extraction by Hierarchical Hough Transform) and ALEGHT(Automatic Lineament Extraction by Generalized Hough Transform) which are merging operation steps through the Hierarchical Hough transform and Generalized Hough transform respectively, are also developed to generate geological lineaments. The merging operation proposed in this study is consisted of three parameters: the angle between two lines($\delta$$\beta$), the perpendicular distance($(d_ij)$), and the distance between midpoints of lines(dn). The test result of the developed algorithm using Landsat TM image demonstrates that lineaments in alluvial plain as well as in rugged mountain is extremely well extracted. Even the lineaments parallel to sun's azimuth angle are also well detected by this approach. Further study is, however, required to accommodate the effect of quantization interval(droh) parameter in ALEGHT for optimization.

• Proceedings of the KAIS Fall Conference
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• 2009.12a
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• pp.350-353
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• 2009

본 연구는 서해안 특성에 적합한 연안역 안전시설 설계기준을 마련을 위해 국내 외 도로, 해안, 항만 구조물의 안전시설기준을 비교, 분석, 정리하였다. 검토된 설계기준은 항만시설물의 안전시설 설계지침,항만 및 어항설계기준, 조경 설계기준, 도로부대시설, 도로교 설계기준, 미국 FHWA DSTA, 그리고 미국 FHWA PFG을 검토하였다. 검토결과 국내의 연안역 안전시설 설계기준 및 적용이 미흡한 상황에 있으며 설계외력산정 및 평가에 적절한 보정계수 및 관련 상세설계기준 마련이 시급한 것으로 판단된다.

• Tunnel and Underground Space
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• v.27 no.4
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• pp.185-194
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• 2017

This technical paper is a study on the unique displacements of Shotcrete Lining at the mined tunnel during excavation period through deep consideration with real time data from monitoring instrumentations correlation with the numerical analysis to identify the rock stresses and the rock spring points at the working face of the Conventional tunnelling by the Drill and Blast, based on the geological face mapping results of the project NS2, Transmission cable tunnel project in Singapore. The created geometry of numerical model was prepared to the real mined tunnel construction site including, vertical shaft, construction adit, tunnel junction area, and 2 enlargement caverns. The convergence measurements by the monitoring instrumentation were performed during the tunnel excavation and shaft sinking construction stages to guarantee the safety of complicated underground structures.

• The Journal of the Convergence on Culture Technology
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• v.9 no.6
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• pp.657-665
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• 2023

Purpose : The purpose of this study is to examine the mediating effect of self-efficacy in the relationship between sense of calling and service quality of personal assistants for people with disabilities. The subjects of this study were personal assistants for people with disabilities belonging to four disability activity support organizations in K-city, Gyeongsangnam-do, and a total of 308 questionnaires were used for the final analysis. The dsta were collected from March 13, 2023 to to April 28, 2023. The collected data were analyzed by frequency analysis, Pearson's coefficents, Baron & Kenny multiple regression analysis using SPSS WIN 24.0. The results of this study are as follows. First, as a result of analyzing the correlation between sense of calling, self-efficacy, and service quality of personal assistants for people with disabilities, it was found that there was a positive correlation in all sub-variables. Second, in the relationship between sense of calling and service quality, self-efficacy was found to have a partial mediating effect. And self-efficacy was found to have a partial mediating effect in the relationship between prosocial orientation, which are sub-factors of sense of calling, and service quality. These results suggest that it is necessary to increase sense of calling and self-efficacy in order to improve the service quality of personal assistants for people with disabilities, and suggestions are made.