• Title/Summary/Keyword: Terrain Data

Search Result 957, Processing Time 0.029 seconds

The Improvement of Point Cloud Data Processing Program For Efficient Earthwork BIM Design (토공 BIM 설계 효율화를 위한 포인트 클라우드 데이터 처리 프로그램 개선에 관한 연구)

  • Kim, Heeyeon;Kim, Jeonghwan;Seo, Jongwon;Shim, Ho
    • Korean Journal of Construction Engineering and Management
    • /
    • v.21 no.5
    • /
    • pp.55-63
    • /
    • 2020
  • Earthwork automation has emerged as a promising technology in the construction industry, and the application of earthwork automation technology is starting from the acquisition and processing of point cloud data of the site. Point cloud data has more than a million data due to vast extent of the construction site, and the processing time of the original point cloud data is critical because it takes tens or hundreds of hours to generate a Digital Terrain Model (DTM), and enhancement of the processing time can largely impact on the efficiency of the modeling. Currently, a benchmark program (BP) is actively used for the purpose of both point cloud data processing and BIM design as an integrated program in Korea, however, there are some aspects to be modified and refined. This study modified the BP, and developed an updated program by adopting a compile-based development environment, newly designed UI/UX, and OpenGL while maintaining existing PCD processing functions, and expended compatibility of the PCD file formats. We conducted a comparative test in terms of loading speed with different number of point cloud data, and the results showed that 92 to 99% performance increase was found in the developed program. This program can be used as a foundation for the development of a program that reduces the gap between design and construction by integrating PCD and earthwork BIM functions in the future.

Generation of Progressively Sampled DTM using Model Key Points Extracted from Contours in Digital Vector Maps (수치지도 등고선의 Model Key Point 추출과 Progressive Sampling에 의한 수치지형모델 생성)

  • Lee, Sun-Geun;Yom, Jae-Hong;Lim, Sae-Bom;Kim, Kye-Lim;Lee, Dong-Cheon
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.25 no.6_2
    • /
    • pp.645-651
    • /
    • 2007
  • In general, contours in digital vector maps, which represent terrain characteristics and shape, are created by 3D digitizing the same height points using aerial photographs on the analytical or digital plotters with stereoscopic viewing. Hence, it requires lots of task, and subjective decision and experience of the operators. DTMs are generated indirectly by using contours since the national digital maps do not include digital terrain model (DTM) data. In this study, model key points which depict the important information about terrain characteristics were extracted from the contours. Further, determination of the efficient and flexible grid sizes were proposed to generate optimal DTM in terms of both quantitative and qualitative aspects. For this purpose, a progressive sampling technique was implemented, i.e., the smaller grid sizes are assigned for the mountainous areas where have large relief while the larger grid sizes are assigned for the relatively flat areas. In consequence, DTMs with multi-grid for difference areas could be generated instead of DTMs with a fixed grid size. The multi-grid DTMs reduce computations for data processing and provide fast display.

Construction of Land Information System using Three Dimensional Digital Elevation Model Algorithm (3차원 지형모델 알고리즘을 이용한 토지정보체계 구축)

  • Kang, Ho-Yun;Chang, Yong-Ku;Kang, In-Joon
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.4 no.3
    • /
    • pp.31-40
    • /
    • 2001
  • Geography Information System is divided to many details fields such as Urban Information System, Land Information System, Military Information System etc. These detailed fields are connected each other and make National Geography Information System. Now Geography Information System is being used in many fields with Urban Information System. And information of all field is being constructed to network for share each other. Now Land Information System(LIS) is being constructed to two dimensional. But LIS can construct and utilize three dimensional geographic data by connecting Geography Information System and this effect will be greatest. Thus, the study of connecting cadastral map and digital terrain map must be continued. Through the study of connecting digital terrain map, the construction and analysis of three dimensional digital elevation model will be able to construct Land Information System effectively. To this study, the authors constructed integrated geographic data by uniting digital terrain map and cadastral map and constructed three dimensional digital elevation model. By connecting cadastral information database, the authors developed three dimensional Integrated Land Information System.

  • PDF

An Assessment on the Hydraulic Characteristics of a Multi-dimensional Model in Response to Measurement Resolution and Spatial Interpolation Methods (지형자료의 해상도와 공간보간기법에 따른 다차원 수리모형의 유출 특성 평가)

  • Ahn, Jung-Min;Park, In-Hyeok
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.20 no.1
    • /
    • pp.43-51
    • /
    • 2012
  • Due to the increasing demand to utilize water fronts and water resource effectively, a multi-dimensional model that provides detailed hydraulic characteristics is required in order to improve the decision making process. An EFDC model is a kind of multi-dimension model, and it requires detailed 3D (3-dimensional) terrain in order to simulate the hydraulic characteristics of stream flow. In the case of 3D terrain creation, especially river reaches, measurement resolution and spatial interpolation methods affect the detailed 3D topography which uses input data for EFDC simulation. Such results make hydraulic characteristics to be varied. This study aims to examine EFDC simulation results depending on the 3D topographies derived by separate measurement resolution and spatial interpolation methods. The study area is at the confluence of the Nakdong and Kuemho Rivers and the event rain implemented was Typhoon Ewiniar in 2006. As a result, in the case of the area-elevation curve, the difference by means of the interpolation methods was significant when applying the same measurement resolution, except at 160m resolution. Furthermore, when the measurement resolution was 80m or above, the difference in a cross-section was occurred. Meanwhile, the water level changes between interpolation methods were insignificant by the measurement resolution except when the Kriging method was used for the 160m measurement data. Velocity changes emerged according to the interpolation methods when measurement resolution was 80m or above and the Kriging method resulted in a velocity that had a considerable gap in relation to the results from other methods at a measurement resolution of 160m.

A Study on morphological characteristics of large river channel based on bathymetry and near-river survey (하천측량을 통한 대하천 유로의 형태학적 특성에 관한 연구)

  • Ko, Joo Suk;Kwak, Sunghyun;Lee, Kyungsu;Lyu, Siwan
    • Journal of Korea Water Resources Association
    • /
    • v.52 no.2
    • /
    • pp.163-172
    • /
    • 2019
  • The linear and cross-sectional shapes of the natural river channel are subjected to continuous changes in time and space due to the interaction with the flow of water and sediment transport. This study aims to investigate the morphological characteristics and change patterns of river channel quantitatively for the middle reach of Nakdong River, which has undergone large scale riverbed dredging and construction work, as Four Major River Restoration Project. A series of bathymetry and near-river survey has been conducted to obtain the detailed terrain information for the study area. The properties related to the linear and cross-sectional characteristics of river channel have been calculated based on the filed survey data and analyzed with comparing the survey data obtained in 2012 for the project completion. Since there has not been enough time for meaningful terrain change to take place, it was not possible to extract special tendency in the degree and aspect of terrain change. However, it is necessary to make regular examinations to the patterns and degree of river channel change using the proposed methodology.

Comparison of Terrain Changes in Debris Flow-Damaged Area and Morpho2DH Model Results (토석류 피해지의 지형 변화와 Morpho2DH 모형 결과의 비교 분석)

  • Jong-Seo Lee;Kwang-Youn Lee;Suk-Hee Yoon;Dong-Hyun Kim;Sang Ho Lee;Se-Wook Oh;Dong-Geun Kim
    • Journal of Korean Society of Forest Science
    • /
    • v.113 no.3
    • /
    • pp.339-348
    • /
    • 2024
  • Debris flow is a typical type of mountainous sediment disaster that can cause widespread damage to both lives and property, making it essential to understand its behavioral characteristics for effective prevention. In this study, pre- and post-event Light Detection And Ranging(LiDAR) data from the Dosan-ri area in Bonghyeon-myeon, Yeongju-si, Gyeongsangbuk-do, Republic of Korea where debris flows occurred in 2023, were used to calculate the actual affected area and terrain change volume caused by the debris flow. These calculated values were then compared with those derived from the numeric simulation model, Morpho2DH, based on field surveys and laboratory investigation data. Additionally, the model's applicability was assessed by conducting cross-sectional elevation analyses based on the extent of the affected area and comparisons of the results. The findings indicate that the debris flow affected area and terrain change volume estimated by the Morpho2DH model were approximately 152% and 178% higher, respectively, compared to the LiDAR-based results. Pearson correlation analysis of the cross-sectional elevation changes showed a positive correlation, with Pearson Correlation Coefficients(PCC) of at least 0.65

Analysis of Inundation Causes in Urban Area based on Application of Prevention Performance Objectives (도시유역에서의 방재성능목표 적용과 침수원인 분석)

  • kim, Jong-Sub
    • Journal of Wetlands Research
    • /
    • v.18 no.1
    • /
    • pp.16-23
    • /
    • 2016
  • The purpose of this study is to analyze quantitatively the inundation causes by applying the prevention of performance objectives using the urban storm water runoff model XP-SWMM. The model was built by using DTM and storm sewer-network with the storm sewer and geo-data of the study area as input-data to assess the current performance of prevention. An analysis of the causes of the inundation by the frequency and the rainfall-duration. As a result, lack of pipe capacity due to flooding, as well as inundation heavier that the backwater rainfall occurs due to the rise of water level of outside. For solve the inundation damage, It is necessary to improvement pipe of capacity lack and installation of a flood control channel.

Analyzing the Disaster Vulnerability of Mt. Baekdusan Area Using Terrain Factors (지형 요소를 고려한 백두산 지역의 위험도 분석)

  • Choi, Eun-Kyeong;Kim, Sung-Wook;Lee, Young-Cheol;Lee, Kyu-Hwan;Kim, In-Soo
    • Journal of the Korean earth science society
    • /
    • v.34 no.7
    • /
    • pp.605-614
    • /
    • 2013
  • Most steep slope failures tend to take place in geographically unstable areas. Mt. Baekdusan is known as a potentially active volcano in a typical mountainous terrain. This study prepared a digital elevation model of Mt. Baekdusan area and created a hazard map based on topographical factors and structural lineament analysis. Factors used in vulnerability analysis included geographical data involving aspect and slope distribution, as well as contributory area of upslope, tangential gradient curvature, profile gradient curvature, and the distribution of wetness index among the elements that comprise topography. In addition, the stability analysis was conducted based on the lineament intensity map. Concerning the disaster vulnerability of Mt. Baekdusan region, the south and south west area of Mt. Baekdusan has a highest risk of disaster (grade 4-5) while the risk level decreases in the north eastern region.

A Evaluation of Standard Support Pattern for Two-Arch Road Tunnel (2-Arch 도로터널에 적용된 표준지보패턴의 적정성 검토)

  • Chun, Byungsik;Choi, Kwangbo;Kim, Hyeyang;Yoo, Junhee
    • Journal of the Korean GEO-environmental Society
    • /
    • v.9 no.7
    • /
    • pp.25-35
    • /
    • 2008
  • In domestic cases, the standard support pattern of 2-lanes road tunnels is presented because construction experience and high degree various data was abundant. But, it is not desirable to apply standard for 2-Arch tunnels that the precedent and measuring data is insufficient existing support pattern blasting plan and interpretation of separate way concerning specific terrain and rock quality. In this study, behavior according to load distribution ratio and Unsymmetrical Pressure about standard support pattern which is applied in design and construction of 2-arch tunnels was analysed and the examination of blasting vibration has influence on the center wall is conducted as a consequence reasonableness of support whether or not with presumed support pressure and ground reaction curve method. In result appropriateness of standard support pattern, support quantity is proper but considers specific terrain and rock quality condition when design and construction of further step 2-arch tunnel standard support pattern must be decided by considering terrains, soil properties and construction condition of the objective tunnel.

  • PDF

Calculation of Effective Receiving Electric Field Level using the Measurement Analysis from Actual Domestic DTV Environment (국내 디지털 TV방송 환경 측정결과 분석을 통한 효과적인 수신전계강도 산출)

  • Choi, Sung-Woong;Lee, Kyung-Ryang;Yang, Chung-Mo;Kim, Seong-Kweon
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.35 no.7A
    • /
    • pp.725-730
    • /
    • 2010
  • Preparing the conversion to the digital broadcasting system, we are deciding broadcasting network plan and interference protection area, using the measured receiving electric field level from the digital broadcasting station. However, the essential researches are needed about a receiving electric field level, because a digital TV (DTV) broadcasting receiver has been improved and an actual receiving environment should be considered. In this paper, the measured data were classified with domestic terrain of line of sight (LOS) and those of non-LOS, and effective receiving electric field level was proposed based on the LOS data. It is known that receiving electric field-level of 48 ㏈uV/m or more should be required for receiving rate of 90% and 50 ㏈uV/m for that of 95%, on the basis of the information of domestic terrain LOS.