• Journal of Satellite, Information and Communications
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• 제9권3호
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• pp.70-73
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• 2014

In this paper, we measure and analyze strength of Beacon signal in Picocell environment by using the frequency of WiFi of ISM band. It is displaying the value what measured by using a beacon signal measurement smartphone app in using AP area, on Google maps using the PC application. the data measured by using mapped GPS signal and RSSI of beacon signal, and convert this data to Position coordinates for Google map in PC. when use this system, we can understand and analyze changes of radio signal through location where installed AP.

• Transactions of the Korean Society of Mechanical Engineers A
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• 제33권12호
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• pp.1433-1441
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• 2009

In multibody dynamic analysis, one of the most important problems is to reduce computation times for real-time simulation. This paper presents the derivation procedure of equations of motion of a 6${\times}$6 autonomous vehicle in terms of chassis local coordinates which do not require coordinates transformation matrix to enhance efficiency for real-time dynamic analysis. Also, equations of motion are derived using the VT(velocity transformation) technique and symbolic computation method coded by MATLAB. The Jacobian matrix of the equations of motion of a system is derived from symbolic operations to apply the implicit integration method. The analysis results were compared with ADAMS results to verify the accuracy and approve the feasibility of real time analysis.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.257-258
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• 2010

Recently data, which are obtained by the airborne laser scanner system have been utilized to rapidly obtain three-dimensional location coordinates for a large area. According to operation regulation, the distance between a GPS base station and a aircraft GPS is fixed within a radius of 30km. In this paper, we compare data obtained by GPS observation station operated in National Geographic Information Institute with those obtained by GPS base station for making a airborne laser survey.

• Proceedings of the Korean Society of Computer Information Conference
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• 한국컴퓨터정보학회 2018년도 제58차 하계학술대회논문집 26권2호
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• pp.279-280
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• 2018

본 과제는 비행체에 자동제어 시스템인 자동항법비행기능을 탑재한 무인기를 제작한다. 자동항법비행이 가능한 무인기는 사람이 직접 조종하는 기존의 비행체들 보다 정밀하고 섬세한 제어가 가능하며 조종자의 시야가 닿지 않는 곳에서의 비행이 가능하다는 장점을 가진다. 또한 상공에서 영상을 촬영하며 5.8GHz대역의 영상 송 수신기를 통한 실시간 영상 확인이 가능하다. 본 과제는 GPS를 이용한 프로그래밍을 통해 미리 지정한 좌표를 따라 비행이 가능하며 실시간 영상 수신이 가능하기 때문에 사람이 직접 갈 수 없는 오염된 지역 등의 정찰이 가능하고, 비행체에 장착되는 장비에 따라 군용, 소방용 등의 다양한 범위에서의 활용이 가능할 것으로 예상된다.

• Proceedings of the Korea Water Resources Association Conference
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• 한국수자원학회 2004년도 학술발표회
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• pp.804-808
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• 2004

최근 정부의 적극적인 지원으로 남북한 교류사업이 본격적으로 추진되고 있고, 통일에 대한 기대감이 높아가고 있는 지금 어느때보다 북한에 내한 관심이 고조되고 있다. 그동안 북한과 관련된 인구는 정치, 경제, 사회, 문화 등 인문${\cdot}$사회과학분야가 대부분을 차지하였고, 자연과학 및 공학 대한 연구는 상대적으로 빈약한 실정이다(배덕효, 1999). 특히 수자원 관련분야는 최근 몇몇 학자들이 원격탐사 기법을 이용하여 연구를 수행한 바 있으나 그 결과는 매우 미비할 실정이다. 북한은 유역탐사 및 샘플채취 등을 위한 접근자체가 어렵기 때문에 자료의 수집 및 보정에 있어 많은 어려움이 따른다. 따라서 본 연구에서는 지금까지 문헌을 통해서만 소개된 북한지역의 유역특성에 따른 수자원 현황을 분석하기 위해 인공위성자료와 지형자료를 이용한 원격탐사(RS:Remote Sensing) 및 지리정보시스템(GIS:Geographic Information System) 기법을 이용하여 유역의 유출특성을 파악하였다. 대상유역으로 선정한 북한 예성강 유역은 수자원이 풍부하고 유역경사가 비교적 완만하게 구성되어 있다. 또한 용수이용에 있어서도 양수장을 이용하여 관개배수를 시행하는 북한지역의 일반적인 사례와는 달리 신곡저수지, 예의 저수지 등 대규모 저수지를 통한 관개를 시행하고 있어 남한유역과 유사한 점이 많기 때문에 적용에 있어 큰 무리가 없을 것이라 판단하였다. 지형자료 구축을 위한 인공위성 자료는 USGS(US Geological Survey) DEM(Digital Elevation Model) 자료를 이용하였으며, 이를 UTM(Universal Transverse Mercatro) 지구좌표계의 DEM 자료로 변환하였다. 또한 유역의 고도차를 이용한 흐름특성 분석을 위해 수치고도자료를 이용하여 유역흐름특성을 분석할 수 있는 TOPAZ(Topographic PArameteri-Zation) 프로그램을 이용하였다. TOPAZ 프로그램을 통해 분석된 각 격자별 분포형 수문 매개변수는 적합한 관계식을 통해 분포형 유출량을 모의하는데 적용된다.

• Journal of the Korean Association of Geographic Information Studies
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• 제17권4호
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• pp.28-39
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• 2014

Several studies have been performed globally on the construction of integrated systems that are available for the integrated use of 3D geographic information on terrain and oceans. Research on 3D geographic modeling is also facilitated by the application of Lidar surveying, which enables the highly accurate realization of 3D geographic information for a wide area of land. In addition, a few marine research organizations have been conducting investigations and surveying diverse ocean information for building and applying MGIS(Marine Geographic Information System). However, the construction of integrated geographic information systems for both terrain and oceans has certain limitations resulting from the inconsistency in reference systems and datum levels between two data. Therefore, in this investigation, integrated geospatial information has been realized by using a combined topographical map, after matching the reference systems and datum levels by integration of airborne Lidar data and multi-beam echo sounder data. To verify the accuracy of the integrated geospatial information data, ten randomly selected samples from study areas were selected and analyzed. The results show that the 10 analyzed data samples have an RMSE of 0.46m, which meets the IHO standard(0.5m) for depth accuracy of hydrographic surveys.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• 제28권5호
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• pp.485-491
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• 2010

Acquisition of information on failure slope, which may cause apprehension of second hand damage, requires acquisition of fast and accurate topographical data and efficient expression in indirect surveying method without accessing as needed. Therefore, in this study, the images on the intended area were photographed through hovering in the air by approaching collapsed road cut slope with the use of unmanned helicopter photography system. As a result of comparing the points observed by no prism total station and the 10 coordinate points analyzed through image analysis, the averages of absolute values were shown to be 0.056m in X axis direction, 0.082m in Y axis direction and 0.066m Z axis direction. In addition, the RMSE of the error for 10 points of test points were 0.015636m in X axis direction, 0.021319m in Y axis direction and 0.018734m in Z axis direction. Therefore, this method can determine the range of slope and longitudinal and cross sections of each slope in dangerous area that cannot be approached in relational image matching method for the terrains of such collapsed cut slope.

• Journal of the Korea Institute of Information and Communication Engineering
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• 제23권11호
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• pp.1428-1433
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• 2019

Interest in mountain accidents among the technical trends of disasters in Korea is increasing continuously. When accidents occur, the most common methods are location tracking and accident reporting using smartphones, and rescue activities are being carried out by using them. In this paper, we proposed an improvement of wireless safety system for mountain climbing safety using 447 FSK. Using the 447 MHz band transmitter / receiver, it accumulates position coordinates and data through position transmission and rescue signal transmission in case of anomalies. If a sender is out of the threshold of the set area range, a danger warning notification can be generated to quickly exit the danger zone. Provide services. In addition, it is considered that the health condition of the sender is continuously checked and the receiver is warned when the specified threshold is exceeded, so that it is possible to respond to the sender's disaster.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• 제31권3호
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• pp.199-207
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• 2013

In hydrographic survey, data surveyed with multibeam system includes various errors due to multiple factors. These are corrected by a calibration called patch test, and if existing method is used, the test needs to be conducted for about 8 times for precise system calibration. For more prompt and precise multibeam system calibration, the exact offset of a ship was determined using terrestrial laser scanning and TS surveying, which was used as the initial input for the patch test. In the result, the error of closure was 0.001 m or less for TS surveying and backsight error was 0.005 m or less for scanning. All the surveying data based on the same local coordinate was converted into vessel reference coordinate during which R-square for all rotation angles was 0.99 or higher and standard deviation was 0.008 m or less. Finally, in a patch test using calculated offset of sensors and motion sensor offset, the offset of MBES transducer satisfied manual on hydrography only with 1-time calibration. With these results, it is thought that terrestrial laser scanning and TS surveying can fully be utilized for multibeam system calibration.

• Journal of KIISE:Computer Systems and Theory
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• 제30권11호
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• pp.621-628
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• 2003

This paper addresses a method of enabling objects in an image to have apparent 3D motion. Many researchers have solved this issue by reconstructing 3D model from several images using image-based modeling techniques, or building a cube-modeled scene from camera calibration using vanishing points. This paper, however, presents the possibility of image-based motion without exact 3D information of scene geometry and camera calibration. The proposed system considers the image plane as a projective plane with respect to a view point and models a 2D frame of a projected 3D object using only lines and points. And a modeled frame refers to its vanishing points as local coordinates when it is transformed.