• Korean Journal of Remote Sensing
• /
• v.36 no.2_1
• /
• pp.179-197
• /
• 2020

Topographic normalization reduces the terrain effects on reflectance by adjusting the brightness values of the image pixels to be equal if the pixels cover the same land-cover. Topographic effects are induced by the imaging conditions and tend to be large in high mountainousregions. Therefore, image analysis on mountainous terrain such as estimation of wildfire damage assessment requires appropriate topographic normalization techniques to yield accurate image processing results. However, most of the previous studies focused on the evaluation of topographic normalization on satellite images with moderate-low spatial resolution. Thus, the alleviation of topographic effects on multi-temporal high-resolution images was not dealt enough. In this study, the evaluation of terrain normalization was performed for each band to select the optimal technical combinations for rapid and accurate wildfire damage assessment using PlanetScope images. PlanetScope has considerable potential in the disaster management field as it satisfies the rapid image acquisition by providing the 3 m resolution daily image with global coverage. For comparison of topographic normalization techniques, seven widely used methods were employed on both pre-fire and post-fire images. The analysis on bi-temporal images suggests the optimal combination of techniques which can be applied on images with different land-cover composition. Then, the vegetation index was calculated from the images after the topographic normalization with the proposed method. The wildfire damage detection results were obtained by thresholding the index and showed improvementsin detection accuracy for both object-based and pixel-based image analysis. In addition, the burn severity map was constructed to verify the effects oftopographic correction on a continuous distribution of brightness values.

• Journal of Korean Society for Geospatial Information Science
• /
• v.2 no.2 s.4
• /
• pp.89-98
• /
• 1994

Digital road map - which plays an essential role in giving accurate location of the vehicle, optimum route guidance, destination searching, and topographic feature query functions - is the most fundamental element of the vehicle navigation system. Unfortunately, there is not a nation-wide digital map in Korea such as U.S. TIGER fie, that is easily applied to digital road database production. Therefore, producing new digital road map is inevitable in Korea For establishing digital road map for vehicle navigation, this paper puts forth the necessary condition to stabilize the digital road map qualify, and to keep up the compatibility and the economical use. As a result, the standards of coordinate and map accuracy arc presented, and the Items and the structures of database arc decided.

• Journal of Korean Society for Geospatial Information Science
• /
• v.5 no.2 s.10
• /
• pp.207-220
• /
• 1997

This study aims to develope the production method of digital image map of high capable utiliy and terrain interpretability using aerial photo and Geospatial Information System. Theory and efficient practical method was studied to generate tile digital image map with low-cost personal computer system using the merging procedure of raster scanned aerial photo and vector topographic map. Determination theory of ground coordinates, digital image processing, production of digital elevation model was reviewed. And some chariteristics of digital image map, image collection method and significant concepts of digital image processing was studied. Also input and output way of image data to generate the digital image nap, production method of orthophoto map using aerial photo through digital differential rectification was studied. As the result, digital image map was produced and analyzed through the above mentioned procedures.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.19 no.4
• /
• pp.343-355
• /
• 2001

The choice of map projection method is depend on the desired map purpose because there is no best projection for maps. Previous projection decisions for published paper maps are not necessarily the right decisions for corresponding digital maps. The map grid and index system is simpler than projection system but it can be easily understanded by general users. In this study, through the study for the grid and index systems of the digital and paper map in our and other countries, I suggested the improvement plan on the problems of our digital map. New grid and index system of this paper are presented on behalf of digital geospatial data which as digital topographic map, digital elevation model and other digital maps.

• Spatial Information Research
• /
• v.9 no.1
• /
• pp.107-124
• /
• 2001

The purpose of this research is to develop system and to establish methodology for managing spatial Database in Land Management Information System(LMIS). Spatial Database which is used by a various public department such as parcel survey and registry, land use planning and Land value appraisal in local government, is composed of parcel map, topographic map and zoning map. Spatial data has been constructed and managed by various department and then hard to maintain accuracy and coinsistency. So, it is important to establish the basic data management concept that source data(ex : parcel map, topographic map, zoning map, etc.) should be managed by responsible department. at the same time, application data for bussiness (ex : individual parcel price map) must be recomposed from base map by it's own objects. This is, Spatial data management system (SDMS) should be designed, developed according to this concept for managing consistency among data, reducing construction and management cost of database. Our SDMS was developed based on Open LMIS middleware architecture using OpenGIS CORBA specification for standard interface, RUP(Rational Unified Process) for development methodology, UML(Unified Modeling Language) for system design and VisiBroker, C++, CAD system for system implementation.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2006.04a
• /
• pp.359-367
• /
• 2006

A map is defined as model of 3D spatial phenomena of the real world. Because most of the maps are represented on the 2D plane, limited information is provided. In consequence, applications are also limited with 2D maps and map users of various fields require 3D form of map. Without doubt, state-of-the-art information technology such as telematics and ubiquitous is location based system, therefore, role of the 3D mapping is getting more significant. It is obvious that 3D maps provide more visual perception than 2D maps. The main object of this stud)r is focused on generation of 3D digital maps in economical and efficient way using photogrammetrically compiled data. Topographic maps are required updating and revision in a certain period and the period is getting shorter Therefore, development of the map editing system is key issue for maintaining quality and updating of the maps to provide reliable geographic information. Special requirements should be taken account into 3D digital map editing. Therefore. design, configuration and functions of the editing system were explored.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.4 no.2
• /
• pp.43-58
• /
• 1986

In a mapping, stereo-restitution of an aerial photogrammetric process, of which is a major factor for map-base preparation dominates the accuracy and the reliability of a topographical map. The majority of a map-base preparation has nowadays been carried out by an analogue method ie, by the stereo-plotter. In consequence, it is evident that the skilled, the level of technique and personal attitude of operator have influence upon observational error which relates the accuracy and the quality of a map. This research aims at detection and analysis of operator's carrier and types of stereoplotter. The test is also examined that the level of details and features of terrain would have influence on the accuracy of map. With the results. it is also considered that the field check has impact on map accuracy ; whether the field check prior to restitution or after restitution.

• Ocean and Polar Research
• /
• v.28 no.4
• /
• pp.467-473
• /
• 2006

The EM 120, a newly installed multibeam echo sounder on RM Onnuri, has several advantages over the previously installed SeaBeam 2000 in performance and thus data quality. The EM 120 system provides a bottom topographic map with high resolution by (1) increasing the number of beams, (2) increasing the across track swath range, (3) measuring the more accurate sound velocity within the water column, and (4) improving stabilization for pitching, rolling, and yawing of the ship. This study compares EM 120 and SeaBeam 2000 echo sounders in terms of the data quality from the same survey area in the Clarion-Clipperton Zone, NE Pacific. Our result shows that the EM 120 provides more precise topographic data than the SeaBeam 2000. Although overall trends of data, such as topographic direction and relief, are similar for both echo sounders, the water depths measured by the EM 120 are shallower than that of SeaBeam 2000 by 80 to 90 meters.

• Journal of Korean Society for Geospatial Information Science
• /
• v.5 no.2 s.10
• /
• pp.169-177
• /
• 1997

The purpose of this paper is to study the ideal Auto-surveying system and to establish the standard of work procedure involved with completing a precise three-dimensional topographic survey with RTK GPS equipment, a pen based personal computer, and real time CADD software. The fieldwork was done at a golf course which could be regarded as a heavy civil project site such as the reclamation and the site preparation work in December of 1997. The proposed Auto-surveying system and the work procedure in this paper is based on the data processing and the resultant topographic map of the golf course.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.16 no.1
• /
• pp.139-147
• /
• 1998

The national topographic basedata should meet a variety of user requirements. To generate, maintain and handle the national topographic basedata in economic and effective way, the nationally supported research works on data model, structure and feature classification system should be intensively undertaken by government agency, research institute and university. This paper presents the technical definitions of conceptual and logical model for proposed data model representing digital map data. The key aspects of the proposed data model are flexibility for accommodating user requirements as well as step-by-step approach for modification as necessary m recent future. Conclusively, the proposed data model is a transitional data model between simple graphical model and object oriented data model.