• Title/Summary/Keyword: geo-field

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A Web Application for Open Data Visualization Using R (R 이용 오픈데이터 시각화 웹 응용)

  • Kim, Kwang-Seob;Lee, Ki-Won
    • Journal of the Korean Association of Geographic Information Studies
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    • v.17 no.2
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    • pp.72-81
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    • 2014
  • As big data are one of main issues in the recent days, the interests on their technologies are also increasing. Among several technological bases, this study focuses on data visualization and R based on open source. In general, the term of data visualization can be summarized as the web technologies for constructing, manipulating and displaying various types of graphic objects in the interactive mode. R is an operating environment or a language for statistical data analysis from basic to advanced level. In this study, a web application with these technological aspects and components is newly implemented and exemplified with data visualization for geo-based open data provided by public organizations or government agencies. This application model does not need users' data building or proprietary software installation. Futhermore it is designed for users in the geo-spatial application field with less experiences and little knowledges about R. The results of data visualization by this application can support decision making process of web users accessible to this service. It is expected that the more practical and various applications with R-based geo-statistical analysis functions and complex operations linked to big data contribute to expanding the scope and the range of the geo-spatial application.

A Terrestrial LiDAR Based Method for Detecting Structural Deterioration, and Its Application to Tunnel Maintenance (터널 유지관리를 위한 지상 LiDAR 기반의 구조물 변상탐지 기법 연구)

  • Bae, Sang Woo;Kwak, Jae Hwan;Kim, Tae Ho;Park, Sung Wook;Lee, Jin Duk
    • The Journal of Engineering Geology
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    • v.25 no.2
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    • pp.227-235
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    • 2015
  • In recent years, owing to the frequent occurrence of natural disasters, the inspection and maintenance of structures have become increasingly important on a national scale. However, because most structural inspections are carried out manually, and due to the lack of objectivity in data acquisition, quantitative data are not always available. As a result, researchers are seeking ways to collect and standardize survey data using terrestrial laser scanning, thereby bypassing the limitations associated with visual investigations. However, field data acquired using a laser scanner have been required to measure changes in structure geometry resulting from passive deterioration. In this study, we demonstrate that it is possible to identify the processes of structural deterioration (e.g., efflorescence, leakage, delamination) using intensity data from terrestrial laser scanning. Additionally, we confirm the viability of automated classification of alteration type and objectification of the polygon area by establishing intensity characteristics. Finally, we show that our method is effective for structural inspection and maintenance.

Selective Removal of Arsenic Compounds from the Contaminated Paddy Soil in China Using Froth Flotation Technique (포말부선 기술을 이용한 중국 오염농경지내 비소화합물의 선택적 제거)

  • Lee, Seungwoo;Jeon, Chilsung;Lee, Eunseong;Yoo, Kyungmin;Choi, Junhyun;Kim, Hyunjung
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.7
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    • pp.343-352
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    • 2016
  • Effects of grinding time and chemicals dosage in arsenic removal from contaminated paddy soil in China were investigated using lab scale attrition and froth flotation combining process. Arsenic concentration in the field soil was 76.51 mg/kg, exceeding Korean and Chinese standards, and predominant arsenic compounds fraction in sequential extraction was "residual" (over 80%). After wet sieving, soil with >2 mm and < 0.038 mm showed concentration lower than 'Warning Level' in Korea. Soil with 0.038-0.075 mm, showing the highest concentration, was discarded since it occupied minor weight fraction (10.1%). Thus soil between 0.075 and 2 mm was only used in the combining process. The highest Arsenic concentration in progeny fragments smaller than 0.038 mm reached up to 981.66 mg/kg after 5 min of attrition. Optimal dosage of collector ($C_5H_{11}OCS_2K$) and modifier ($Na_2S$ and $CuSO_4$) in froth flotation process for the selective separation of the chipped progeny particles from the parent fragments were determined both as 200 g/ton. Arsenic removal efficiency in froth flotation process was 38.47% and it was increased to 72.74% in additional flotation process, scavenging. Average arsenic concentration after overall process - wet sieving, attrition and froth flotation - was estimated to 16.45 mg/kg.

Implementation of Coupled Hydro-Mechanical Problems in Partially Saturated Soils (불포화 지반에 물의 침투와 흙의 변형이 사면의 안정성에 미치는 영향)

  • Kim, Jaehong;Hwang, Youngcheol
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.5
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    • pp.35-43
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    • 2010
  • Partially saturated permeability should be defined by the function of suction (or degree of saturation) and porosity. However, commercial software and most researchers' model often describe as the function of suction. The stability of a soil slope can be affected by both hydraulic and shear strength properties of partially saturated soils. For both studies, we generally use an uncoupled seepage analysis program Seep/W(Geo-Slope, 2007) and a series stress-deformation analysis program Sigma/W, or slope stability analysis program Slope/W. Seep/W is performed for simulations of partially saturated flow problems in non-deformable soil media. However, under real situations, the water flow processes in a deformable soil are influenced by soil skeleton movement and the pore water pressure changed due to seepage will lead to changes in stresses and to deformation of a soil. Many researchers are currently developing their models for solving coupled hydro-mechanical problems to simulate slope stability during a rainstorm. For a proper implementation in the field, the developed model should be still needed in order to achieve appropriate accuracy of the solution for coupled hydro-mechanical problems in soil slope stability. Thus, the paper presents the comparison of slope stability between uncoupled and coupled analyses of seepage and stress deformation problems.

Evaluating a Positioning Accuracy of Roadside Facilities DB Constructed from Mobile Mapping System Point Cloud (Mobile Mapping System Point Cloud를 활용한 도로주변 시설물 DB 구축 및 위치 정확도 평가)

  • KIM, Jae-Hak;LEE, Hong-Sool;ROH, Su-Lae;LEE, Dong-Ha
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.3
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    • pp.99-106
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    • 2019
  • Technology that cannot be excluded from 4th industry is self-driving sector. The self-driving sector can be seen as a key set of technologies in the fourth industry, especially in the DB sector is getting more and more popular as a business. The DB, which was previously produced and managed in two dimensions, is now evolving into three dimensions. Among the data obtained by Mobile Mapping System () to produce the HD MAP necessary for self-driving, Point Cloud, which is LiDAR data, is used as a DB because it contains accurate location information. However, at present, it is not widely used as a base data for 3D modeling in addition to HD MAP production. In this study, MMS Point Cloud was used to extract facilities around the road and to overlay the location to expand the usability of Point Cloud. Building utility poles and communication poles DB from Point Cloud and comparing road name address base and location, it is believed that the accuracy of the location of the facility DB extracted from Point Cloud is also higher than the basic road name address of the road, It is necessary to study the expansion of the facility field sufficiently.

The Effects of the Online Learning Using Virtual Reality (VR) Geological Data: Focused on the Geo-Big Data Open Platform (가상현실(VR) 지질자료 개발을 통한 원격수업의 효과 분석: 지오빅데이터 오픈플랫폼 활용을 중심으로)

  • Yoon, Han Do;Kim, Hyoungbum;Kim, Heoungtae
    • Journal of the Korean Society of Earth Science Education
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    • v.15 no.1
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    • pp.47-61
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    • 2022
  • In this study, We developed VR (Virtual Reality) geological resources based on the Geo Big Data of the Big Data platform that provided by the Korea Institute of Geoscience and Mineral Material (KIGAM). So students selected the theme of lessons by using these resources and we operated Remote classes using the materials that developed as to Virtual Reality. Therefore, the geological theme maps provided by the Geo Big Data Open Platform were reconstructed and produced materials were created for Study about Real Korean geological outcrops grounded in Virtual Reality. And Topographic information data was used to produce class materials for Remote classes. Twenty students were selected by Random sampling, and data were collected by conducting a survey including interviews to confirm the change in students' perception of remote classes in virtual reality geological data development and the effect of the classes, so data were analyzed through inductive categorization. The results of this study are as follows. First, students showed positive responses in terms of interest, utilization, and knowledge utilization as taking remote classes for developing geological data in virtual reality geological data. This is the result of showing the adaptability of diverse and flexible learning getting away from a fixed framework by motivating and encouraging students and inducing cooperation for communication. Second, students recognized distance education in the development of Virtual Reality geological data as 'Realistic hands-on learning process', 'Immersive learning process by motivation', and 'Learning process of acquiring knowledge in the field of earth science'.

A Study on Awareness and Experience of Data Publishing by Scientists (과학기술분야 연구자들의 데이터 출판경험 및 인식 연구)

  • Hyekyong Hwang;Youngim Jung;Sung-Nam Cho;Tae-Sul Seo;Jihyun Kim
    • Journal of Korean Library and Information Science Society
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    • v.54 no.1
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    • pp.45-68
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    • 2023
  • This study aims to investigate the awareness and experiences of domestic researchers regarding data publishing, which has been recognized as a new channel of data sharing as scholarly communication evolves in the open science environment. A survey is conducted among researchers from five government-funded research institutes in the field of science and technology and members of the GeoAI Data Society to confirm the awareness of data publishing. As a result of the study, domestic researchers recognized providing explanations for data, stable access to data, citation, and quality assurance through peer review as the advantages of data journals. On the contrary, a low level of recognition for data paper as one of the research outputs was presented. With regard to the properties of data publication, the respondents answered that the data description, metadata description, and permanent identifiers are highly related, however, their recognition of the relation between the properties of data publication and the data submission to a repository and data peer review was relatively low. Finally, to expand the data publication, the need for the development of an editorial system that supports data paper peer review and cross-linking to a data repository as well as the development of a repository that supports data citation was identified. This study on the domestic researchers' experience and awareness of data publishing can provide insights for the implementation of data publishing services and infrastructure in the future.

A Study on the Reinforcement of Rock Faults by Grouting (암석 절리면의 그라우팅에 의한 보강에 관한 연구)

  • Chun, Byung-Sik;Choi, Joong-Keun
    • Journal of the Korean GEO-environmental Society
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    • v.4 no.4
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    • pp.45-51
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    • 2003
  • Grouting materials in rock is grouted as vein type along the fault surface by the other way for soil and allow a change of characteristics in rock faults as a result of that. Therefore the deformation characteristics of rock faults after grouting differ as a direction and characteristic of grouted fault and stress condition of field rock. Thereby it must be analyzed the effect for deformation of rock according to characteristics of rock faults and characteristics of grouting materials to accurately evaluate the reinforced effect by grouting. But grouting method used in field until present depends on experience of workers, and inspection for those effects are evaluated by measurement of elastic wave velocity, permeability tests and etc. in field. In this study, it was investigated that the effects for shear characteristics of maximum shear strength, residual shear strength and etc. by comparison and analysis of test results which were worked by direct shear tests of rock faults with changing a type of grouting materials and the grouting depth(t) for average width(a) of fault surface roughness when OPC(Ordinary Portland Cement) and Micro cement was grouted in fault surface of field rock to evaluate characteristicsof the shear deformation for rock fault surface of dam by grouting.

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Behavior of Quaywall Pile by Lateral Movement of Revetment on Soft Ground (연약지반 호안의 측방유동에 따른 안벽 말뚝의 거동)

  • Shin, Eunchul;Park, Jeongjun;Ryu, Ingi
    • Journal of the Korean GEO-environmental Society
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    • v.7 no.4
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    • pp.53-62
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    • 2006
  • Recently, the lateral displacement of the passive piles which are installed under the revetment on the soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of ground when the revetment loading exceeds a certain limit. The lateral displacement of ground causes an excessive deformation of underground structure itself and develops lateral earth pressure against the pile foundation. The subject of study is to investigate the lateral displacement of pile foundation during the construction of container terminal at the ${\bigcirc}{\bigcirc}{\bigcirc}{\bigcirc}$ port in Incheon. The displacement of pile and the vertical settlement were measured in the field and finite element method(FEM) analysis for each construction sequence was performed using AFFIMEX(Ver 3.4). From the comparison of the results from field measurement and the finite element analysis, the settlement of the reventment has already occurred at the time of field measurements. Since then, the noticeable lateral displacement of piles and settlement were occurred during the filling of dredged soil inside the revetment dredging and reclaiming work. After completing filling, the lateral displacement and field settlement were reduced remarkably. Generally, the results from the finite element analysis show larger than those from the measurement.

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Application of Non-Alkaline Silica Sol Grouting Method Considering the Eco-Friendliness (친환경 비알칼리성 실리카졸 차수공법의 적용)

  • Jang, Yonggu;Kim, Sugyum;Kang, Injoon
    • Journal of the Korean GEO-environmental Society
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    • v.17 no.9
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    • pp.37-45
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    • 2016
  • This study analyzes the environmental and durability problems of traditional (LW) grouting method. And the proposed method was compared to the others effects by analyzing the in-situ applicability and effect of performance of the method using the silica sol. This study analyzed the eco-friendly, effects of high strength silica sol through laboratory tests. The effects of the construction process were identified through the field tests. The compressive strength was increased by 1.3 times compared to the LW method and the shrinkage is 3~8 times less than that of LW method with water glass. No toxicity, which could affect soil contamination. In particular, it was confirmed that the Toxicity fish also survived with little pH change in the concentration tank. Also it confirmed the construction effects through field test. Field tests are a standard penetration test, permeability test, LLT, BST. Permeability was reduced to $1{\times}10^{-5{\sim}-6}cm/sec$.