• Title/Summary/Keyword: Terrain survey

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A Study on the Safety Assessment of Elementary School Environment in Korea (우리나라 신도시 초등학교의 통학로 안전환경 비교분석에 관한 연구)

  • Yoon, Yong-Gi
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.14 no.2
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    • pp.26-36
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    • 2015
  • The new town was assumed that there is a difference between the country's elementary school environment. First, given the important elements of the school safety plan in order to verify this, and we plan to set up each of these elements by safety criteria. In the second chapter in order to achieve the objective of this study was to develop indicators to evaluate the safety of the school environment influences the safety of the school environment through the theoretical consideration. In Chapter 3, the difference in safety through the new elementary school survey of metropolitan areas was given a score per item per item depending on the evaluation criteria. The fourth section is the difference between safety school environment can be summarized as the following analytical results that the difference between the new city. The results of this study as follows: First, the characteristics of the elementary school environment showed a significant difference between the new town. Second, school location, terrain characteristics, bike paths and pedestrian to the installation, the safety of landscape installations, installing median barriers, traffic safety facilities, speed bumps, separation of pedestrian and vehicle circulation in the front door, scores of elements of the plan such as parking scheme there is a difference between the new town. Third, the introduction of elements of the plan such as Traffic calming or Traffic Island installation techniques was found lacking.

Determination of the Optimal Parameters in Data Processing for the Precision Geoid Construction (정밀 지오이드 구축을 위한 자료처리의 최적 변수 결정)

  • Lee, Ji-Sun;Kwon, Jay-Hyoun
    • Spatial Information Research
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    • v.17 no.3
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    • pp.397-404
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    • 2009
  • To solve the problems of distribution and quality on land gravity data, airborne gravity survey was performed in 2008 obtaining the airborne gravity data with accuracy of 1.56mGal. Since airborne gravity data is the obtained at the flight height, it is necessary to convert the airborne gravity data to the surface to combine various gravity data and compute precision geoid. In addition, Stokes' integral radius, Stokes' kernel and the radius of terrain effect computation should be optimally determined to calculate precision geoid. In this study, we made an effort to decide the optimal parameters based on the distribution and the characteristic of gravity data. Then, two geoid models were calculated using the selected parameters and the difference of geoid was calculated with mean of -16.95cm and the standard deviation of ${\pm}8.50cm$. We consider that this difference is due to the distribution and errors on the gravity data. For future work, the study on the effect of geoid with newly obtained land gravity data ship-borne gravity data and GPS/Leveling data should be conducted. Furthermore, the study on the downward continuation and terran effect calculation should be studied in detail for better precision geoid construction.

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The Evaluation on Accuracy of LiDAR DEM by Plotting Map (도화원도를 이용한 LiDAR DEM의 정확도 평가)

  • 최윤수;한상득;위광재
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.20 no.2
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    • pp.127-136
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    • 2002
  • DEM(Digital Elevation Model) is used widely in image processing, water resources, construction, GIS, landscape architecture, telecommunication, military operations and other related areas. And it is used especially in producing ortho-photo based on specific DEM and developing 3D GIS database vividly. As LiDAR(Light and Detection And Ranging) system emerged recently, DEM could be developed in urban area more efficiently and more economically, compared to the conventional DEM Production. Traditional method using check points for elevation has tome limitations in structure's height accuracy by LiDAR, because it uses only terrain height. Accordingly after the downtown of Chungju city was selected as a test field in this paper and DEM and digital ortho images was produced by way of LiDar survey, the accuracy was evaluated through analytical plotting map. The result shows that in case of buildings in LiDAR DEM, the accuracy is 0.30 m in X, 0.62 m in Y and RMS is 1.17 m. The difference distribution between DEM and plotting map in range of $\pm$10 cm was 36.2% and $\pm$10 cm $\pm$20 cm was 43.53%. The accuracy of LiDAR in this study meets 1/5,000 which is the regulation for map of NGI(National Geography Institute) and LiDAR can be possibly used in many other applied area.

A Study on Conservation and Management of the Joseon Royal Tomb's System - Focused on Joseon Royal Tombs of Middle District in Seoul - (조선왕릉의 능제보존관리에 관한 연구 - 서울 중부지구 조선왕릉을 중심으로 -)

  • Choi, Jong-Hee;Lee, Chang-Hwan;Hwang, Kyu-Man;Kim, Kyu-Yeon
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.4
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    • pp.43-55
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    • 2017
  • The purpose of this study is to investigate conservation and management methods of the Joseon Royal Tombs in the Middle District. Urbanization has damaged many of the original terrains as many buildings and facilities have entered the inner and outer area of Joseon Royal Tombs. Land purchase, relocation and demolition of the building are required for the recovery of the Royal Tombs area, and then it is necessary to recover the original terrain. In the case of land use and pathways, there were many land use which harmed the sacred atmosphere of the area, and many disconnection of the ritual circulation, they should be maintained to remind the sacred atmosphere of the royal tomb. The water system should be changed to natural type canal, and it is necessary to collect accurate information on the lost buildings and stoneworks through literature survey and excavation investigation, and then lead to the exposure or restoration of the ruins. Historical forests require periodic and ongoing monitoring and management, and it is necessary to establish a historical and cultural museum that can provide to visitors information about Joseon Royal Tombs. These works should be classified into short, medium and long-term projects with a long perspective to implement continuous and systematic projects.

Extraction of Individual Trees and Tree Heights for Pinus rigida Forests Using UAV Images (드론 영상을 이용한 리기다소나무림의 개체목 및 수고 추출)

  • Song, Chan;Kim, Sung Yong;Lee, Sun Joo;Jang, Yong Hwan;Lee, Young Jin
    • Korean Journal of Remote Sensing
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    • v.37 no.6_1
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    • pp.1731-1738
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    • 2021
  • The objective of this study was to extract individual trees and tree heights using UAV drone images. The study site was Gongju national university experiment forest, located in Yesan-gun, Chungcheongnam-do. The thinning intensity study sites consisted of 40% thinning, 20% thinning, 10% thinning and control. The image was filmed by using the "Mavic Pro 2" model of DJI company, and the altitude of the photo shoot was set at 80% of the overlay between 180m pictures. In order to prevent image distortion, a ground reference point was installed and the end lap and side lap were set to 80%. Tree heights were extracted using Digital Surface Model (DSM) and Digital Terrain Model (DTM), and individual trees were split and extracted using object-based analysis. As a result of individual tree extraction, thinning 40% stands showed the highest extraction rate of 109.1%, while thinning 20% showed 87.1%, thinning 10% showed 63.5%, and control sites showed 56.0% of accuracy. As a result of tree height extraction, thinning 40% showed 1.43m error compared with field survey data, while thinning 20% showed 1.73 m, thinning 10% showed 1.88 m, and control sites showed the largest error of 2.22 m.

An Analysis of Observational Environments for Solar Radiation Stations of Korea Meteorological Administration using the Digital Elevation Model and Solar Radiation Model (수치표고모델과 태양복사모델을 이용한 기상청 일사 관측소 관측환경 분석)

  • Jee, Joon-Bum;Zo, Il-Sung;Kim, Bu-Yo;Lee, Kyu-Tae
    • Journal of the Korean earth science society
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    • v.40 no.2
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    • pp.119-134
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    • 2019
  • In order to analyze the observational environment of solar radiation stations operated by the Korea Meteorological Administration (KMA), we used the digital elevation model (DEM) and the solar radiation model to calculate a topographical shading, sky view factor (SVF) and solar radiation by surrounding terrain. The sky line and SVF were calculated using high resolution DEM around 25 km of the solar stations. We analyzed the topographic effect by analyzing overlapped solar map with sky line. Particularly, Incheon station has low SVF whereas Cheongsong and Chupungryong station have high SVF. In order to validation the contribution of topographic effect, the solar radiation calculated using GWNU solar radiation model according to the sky line and SVF under the same meteorological conditions. As a result, direct, diffuse and global solar radiation were decreased by 12.0, 5.6, and 4.7% compared to plane surface on Cheongsong station. The 6 stations were decreased amount of mean daily solar radiation to the annual solar radiation. Among 42 stations, eight stations were analyzed as the urgent transfer stations or moving equipment quickly and more than half of stations (24) were required to review the observational environment. Since the DEM data do not include artifacts and vegetation around the station, the stations need a detail survey of observational environment.

Uncertainty Analysis of BAG by GNSS Correction (해저지형 표면자료의 GNSS 보정방법에 따른 불확실도 연구)

  • OH, Che-Young;KIM, HO-Yong;LEE, Yun-Sik;CHOI, Chul-Uong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.3
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    • pp.1-9
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    • 2019
  • In the recent marine sector, the development and standardization regarding S-100, which is the universal hydrographical data model standard for development of marine space information, was progressed, and for the effectiveness of marine chart production work and the multi-purpose use of water level data in S-100, S-102(Bathymetric Surface grid) standard development and various studies of BAG formats combined with water level and uncertainty, property information is being progressed. Since the water level information that is important in the operation of the ship is provided based on S-102, the calibration method of the location information when producing S-102 is an important factor in deciding the water level. In this study, the hydrographical surveying was conducted by piloting the standardized method for the production of S-102 in Korea, and have compared the accuracy of water level information according to the GNSS post treatment calibration method. As a result of comparing the water level in 2 places in the rocky terrain of the study area, the northern water level of Namu-do was shown as DL 0.79~0.83m, the eastern water level of Daeho-do was DL 12.63~12.91m, and the horizontal position errors of the intermittent sunshine water level were confirmed to be within 1m. As a result, the intermittent sunshine water level according to the location calibration method when producing the BAG was confirmed that it was in the available range for a ship's safe voyage. However, the accuracy verification for the location of the ship when conducting hydrographical surveying was judged that there is a need for a various additional study about regional characteristics and environment factor.

Status of Exotic Plant Species in Gyeongju Yangdong Village (경주 양동마을의 외래식물 현황)

  • Kim, Gi Song;Shin, Hyun Tak;Yi, Myung Hun;Yoon, Jung Won;Kim, Yong Shik
    • Korean Journal of Heritage: History & Science
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    • v.45 no.1
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    • pp.174-189
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    • 2012
  • This study aims to examine the traditional living space to reflect the environment-friendly design methods and principles of reestablishment. To do so, this study carried on a related literature study and field survey. The traditional living space in terms of the environmental friendliness is reflected on site selection and space composition, and utilization of natural energy and natural materials. Focused on the Kwangajeong in Yangdong Village, this study is to identify eco-friendly techniques on the traditional living space. As a result, it shows that Kwangajeong with the side of the southeast in site selection had been considered in aspect of environmental control such as sunshine and solar radiation. Also building construction techniques had been used to minimize the variation of terrain. In aspect of environmental conservation, Kwangajeong had structurally arranged the gate, an inner yard and an inner floor to allow good ventilation. In aspect of space composition, Kwangajeong with the emphasis of scenic view had utilized the methods that attract external landscape through the control of its fences. Environment-friendly techniques and control principles in traditional space had been developed by a long experience through the long periods and the traditional techniques suitable for local climate and local environment have been developed. The technical development of these techniques to resolve the global environmental and energy issues and create a more pleasant living environment of human beings might be critical.

A Study on the Environment-friendly Planning Elements on High-Class Houses Kuangajeong in Chosun Dynasty (관가정(觀稼亭)으로 본 조선시대 상류주택의 환경친화적 계획요소 분석)

  • Heo, Jun;Lee, Shi Young;Song, Byeong Hwa
    • Korean Journal of Heritage: History & Science
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    • v.44 no.3
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    • pp.164-177
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    • 2011
  • This study aims to examine the traditional living space to reflect the environment-friendly design methods and principles of reestablishment. To do so, this study carried on a related literature study and field survey. The traditional living space in terms of the environmental friendliness is reflected on site selection and space composition, and utilization of natural energy and natural materials. Focused on the Kwangajeong in Yangdong Village, this study is to identify eco-friendly techniques on the traditional living space. As a result, it shows that Kwangajeong with the side of the southeast in site selection had been considered in aspect of environmental control such as sunshine and solar radiation. Also building construction techniques had been used to minimize the variation of terrain. In aspect of environmental conservation, Kwangajeong had structurally arranged the gate, an inner yard and an inner floor to allow good ventilation. In aspect of space composition, Kwangajeong with the emphasis of scenic view had utilized the methods that attract external landscape through the control of its fences. Environment-friendly techniques and control principles in traditional space had been developed by a long experience through the long periods and the traditional techniques suitable for local climate and local environment have been developed. The technical development of these techniques to resolve the global environmental and energy issues and create a more pleasant living environment of human beings might be critical.

A Study on the Accuracy of GNSS Height Measurement Using Public Control Points (공공기준점을 이용한 GNSS 높이측량 정밀도 분석 연구)

  • WON, Doo-Kyeon;CHOI, Yun-Soo;YOON, Ha-Su;LEE, Won-Jong
    • Journal of the Korean Association of Geographic Information Studies
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    • v.24 no.2
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    • pp.78-90
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    • 2021
  • In order to construct a precision geoid, it has been diversified into land, sea, aviation, and satellite gravity measurement methods, and measurement technology has developed, making it possible to secure high-resolution, high-precision gravity data. The construction of precision geoids can be fast and conveniently decided through GNSS surveys without separate leveling, and since 2014, the National Geographic Information Institute has been developing a hybrid geoid model to improve the accuracy of height surveying based on GNSS. In this study, the results of the GNSS height measurement were compared and analyzed choosing existing public reference points to verify the GNSS height measurement of public surveys. Experiments are conducted with GNSS height measurements and analyzed precision for public reference points on coastal, border, and mountainous terrain presented as low-precision areas or expected-to-be low-precision in research reports. To verify the GNSS height measurement, the GNSS ellipsoid height of the surrounding integrated datum to be used as a base point for the GNSS height measurement at the public datum. Based on the checked integrated datum, the GNSS ellipsoid of the public datum was calculated, and the elevation was calculated using the KNGeoid18 model and compared with the results of the direct level measurement elevation. The analysis showed that the results of GNSS height measurement at public reference points in the coastal, border, and mountainous areas were satisfied with the accuracy of public level measurement in grades 3 and 4. Through this study, GNSS level measurement can be used more efficiently than existing direct level measurements depending on the height accuracy required by users, and KNGeoids 18 can also be used in various fields such as autonomous vehicles and unmanned aerial vehicles.