• Journal of the Korean Association of Geographic Information Studies
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• v.10 no.4
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• pp.97-110
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• 2007

A laser scanning technique has been attracting much attention as a new technology to acquire location information. This technique might be applicable to a wide range of areas, most notably in geomatics, due to its high accuracy of location and automation of high-density data acquisition. A alignment information extraction system on highway has been developed in this study by utilizing the advantages of the laser scanning technique. The system can accurately interpret the alignment information of highway and can be applied to actual works. To develop the alignment information extraction system on highway, an algorithm that can automatically separate a horizontal alignment into a straight line, a transition curve, and a circular curve was developed. It can increase its efficiency compared to the conventional methods. In addition, an algorithm that can automatically extract design elements of horizontal and vertical alignments of highway was developed and applied to an object highway. This yielded higher practicality with more accurate values compared to those from previous studies on the extraction of design elements of highway alignment. Furthermore, the extracted design elements were used to perform a virtual driving simulation on the object highway. Through this, data were provided for a visual judgment for judging visually whether the topography and structures were harmonized in a three-dimensional manner or not. The study also presents data that can serve as a basis to determine highway surface freezing sections and to analyze three-dimensional sight distance models. Through the establishment of a systematic database for diverse data on highway and the development of web-based operating programs, an efficient highway maintenance can be ensured and also they can provide important information to be used when estimating a highway safety in the future.

• Spatial Information Research
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• v.2 no.1
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• pp.93-101
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• 1994

A river space means the river related environments such as rIver and floodplain. Because river space data include two-dimensional and three¬dimensional characters. geographic informat ion system is an effect ive tool to manage the data. The objective of this study is to construct the pilot system called RSDB '93 and to simulate the system in practical aspects. The local area for the study was limited about 12km from Jamsil cheolgyo to Dongjak daegyo of the Han River. PC ARC/INFO was selected which can be used on PC 386DX. The Graphic data in an establ ished database contain river layer. floodplain layer. road layer. profile site and hydraulic structure site8 layer. Attributes include water prof i Ie. ut i I i ty status. ecological data. landmark data. hyd¬rology data. water quality data. aerial photo and other photos. RSDB '93 is a system presenting the potentials for the effective river space management which can be applied to all the domestic rivers.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.7
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• pp.1559-1566
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• 2012

This paper proposed the method to find out the optimal sensing point of temperature in test-bed with the sensor of temperature, such as real residence. We selected optimal locations by checking temperature change which was simulated by the means of CFD (Computational Fluid Dynamics) and the variation of air flow. We made 3-dimensional model of the testbed using DesignBuilder software, and ran the CFD. We selected the optimum temperature measurement location of 1.5 m height from the floor and low temperature variation. The experiments were conducted 30 temperature and humidity sensors in real place. After that, we confirmed the results of temperature change.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.10a
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• pp.13-15
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• 2008

LiDAR(Light Detection and Ranging)는 3차원공간정보를 신속하게 구축할 수 있는 최신 측량 기술로써 최근 그 활용도와 중요성이 높아지고 있다. 그러나 LiDAR 관측성과는 시스템 특성상 높은 수직 정확도를 제공하고 있으나 항공사진과 같이 정확한 평면위치를 측정하여 조정할 수 없으므로 상대적으로 낮은 수평 정확도를 가지고 있다. 본 연구에서는 LiDAR 관측에 의한 건물의 벽면 반사파를 이용하여 건물모서리의 평면 좌표(x, y)를 추출하고, 이를 항공삼각측량에 의한 평면좌표와 비교분석하였다. 그 결과 LiDAR의 평면좌표가 항공삼각측량에 의한 평면좌표에 비해 상대적으로 이동되어 있음을 확인할 수 있었다. 따라서, 2차원 좌표변환을 수행하여 LiDAR의 평면좌표를 보정하여 정확도를 향상시킬 수 있었고, 이를 이용하여 향후 LiDAR 관측성과 품질 향상에 도움이 될 것이라 기대한다.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.2
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• pp.55-67
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• 2005

This study presented the route location method by applying AHP and evaluating quantitatively. This study developed the program that can be easily applied to this kind of road design, and built the decision support system for route location. The study results are summarized as follows ; We could quantitatively evaluate the appropriateness of exiting routes by applying the AHP based on GIS. If we apply this to the roads that will be newly constructed, we can make the objective and reliable route location when making road plans and basic designs. We improved the technique of route location by applying the decision support system with third-dimensional data, which considers even the vertical alignment plan, to the existing decision support system with second-dimensional data. And, since we can set those data such as vertical slope, earth-volume, structure size, location and construction cost to independent variables, we can make road designs more scientifically and reasonably.

• Journal of Satellite, Information and Communications
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• v.8 no.1
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• pp.40-44
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• 2013

In this paper, we describe on the position error of GBAS. In reality, there are many sources which make errors into the calculation of receiver position. It is well known that the DOP of GBAS is an important position error source and is dependent on the numbers and positions of the transmitters. Here, we develop an algorism to calculate the DOP of the GNSS with 2-line transmitters into Korean area. The result is useful to predict the DOP of the positions where transmitters and receivers are located.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.12 no.1
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• pp.89-94
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• 1994

A number of the latest research projects focus on the development of real-time mapping system. Typically, these devices are used to capture land-related information in digital form from airplanes or cars. The purpose of this paper is to automatically extract the road information from the digital images obtained using the so-called "GPS-Van" which has been developed by Center for Mapping at The Ohio State University, and to propose the method for the effective storage and management of the digital data. The edges of a road can be extracted from the digital image and determined real-time 3-dimensional position by digital photogrammetry. Also, the three storage level which consists of raster data level, object-oriented data level, and vector data level in the data storage and Quadtree data structure for the effective compression and search in the data management was proposed in this paper.his paper.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1991.10a
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• pp.97-115
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• 1991

본 시스템은 주어진 건축 부지위에 최대 건축 가능 공간을 산정한다. 한국 건축법규와 건축조례를 검토하여 가능공간을 산정하며 입력 데이타로는 부지 및 도로의 도형정보 및 부지의 위치정보등을 사용한다. 본 시스템은 일반적인 CAD S/W와 달리 Non-geometric 데이터를 많이 포함하여 데이터 구조 부분이 타 시스템과 많은 차이가 있으므로, 그에 따른 알고리즘을 자체 개발 적용하였다. 본 시스템은 건축 법규 추론 시스템의 결과에 따라 건축 가능 공간을 솔리드 모델로 생성한다. 이를 위해 평면만을 가지는 경계 표현법(B-Rep)솔리드 모델링 기능이 사용되었으며 생성되는 솔리드 모델은 Half-Edge데이터 구조로 저장되며 물성치 계산 기능, 은선제거기능, 음영처리기능들이 개발되었다. 적용시 각 단계를 시각화하고 출력하여 지금까지의 수작업을 배제하고 정확한 결과를 얻게 하여 설계시간을 최소화하고 건축주에게 만족한 결과를 얻게 한다.

• Smart Media Journal
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• v.2 no.4
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• pp.60-65
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• 2013

In this paper, we propose a high-resolution disparity map generation method using a low-resolution time-of-flight (TOF) depth camera and color camera. The TOF depth camera is efficient since it measures the range information of objects using the infra-red (IR) signal in real-time. It also quantizes the range information and provides the depth image. However, there are some problems of the TOF depth camera, such as noise and lens distortion. Moreover, the output resolution of the TOF depth camera is too small for 3D applications. Therefore, it is essential to not only reduce the noise and distortion but also enlarge the output resolution of the TOF depth image. Our proposed method generates a depth map for a color image using the TOF camera and the color camera simultaneously. We warp the depth value at each pixel to the color image position. The color image is segmented using the mean-shift segmentation method. We define a cost function that consists of color values and segmented color values. We apply a weighted average filter whose weighting factor is defined by the random walk probability using the defined cost function of the block. Experimental results show that the proposed method generates the depth map efficiently and we can reconstruct good virtual view images.

• Journal of KIISE:Computer Systems and Theory
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• v.26 no.1
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• pp.82-97
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• 1999

3차원 그래픽 렌더링은 화면상의 각 화소에 대하여 색깔뿐만 아니라 깊이 정보가지 계산해야 하기 때문에 방대한 계산량과 메모리 접근, 그리고 데이터 전송량을 필요로 하기 때문이다. 따라서 실시간 3차원 그래픽 처리를 위해서 병렬 처리 기법을 도입한다. 그러나 기존 그래픽 가속엔진은 병렬처리 기법으로 영상-병렬성을 이용한 화면 분할 방식을 사용하기 때문에 크게 두 가지 단점이 발생한다. 첫 번재는 화면 영역의 경게에 위치하는 다각형들에 대한 중복계산이고, 두 번째는 낮은 PE(Processing Element) 활용도이다. 본 논문에서는 이러한 문제를 해결하기 위한 방법으로 객체 기반 렌더링(OBR : Object Based Rendering)방식을 바탕으로 하는 그래픽 가속엔진을 제안하였다. OBR 시스템의 목적은 화면 분할 방식의 불필요한 오버헤드를 제거하여 수행 성능을 높이고, 자원을 효율적으로 사용하여 하드웨어 구성비용을 줄이는 것이다. 본 논문에서는 시뮬레이션을 통하여 OBR 시스템이 화면 분할 방식의 대표적인 그래픽 가속기인 PixelFlow와의 성능을 상대적으로 비교하였다. 결론적으로 OBR 시스템은 화면 분할 방식보다 더 적은 하드웨어 자원으로 보다 효율적으로 렌더링을 수해하였다.