• 대한공간정보학회지
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• 제10권3호
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• pp.115-122
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• 2002

위성으로 취득되는 영상이 원천적으로 가지게 되는 기하적, 물리적인 왜곡을 제거하기 위해서는 보정 과정이 필요하다. 기하 보정 방법에는 시스템 기하보정과 지상기준점을 이용한 기하보정 방법이 있는데, 본 논문에서는 지상기준점을 이용한 보정 방법에 대해 기술하고 TIN 단위로 기하보정하는 방법을 제안한다. 영상과 지상기준점과의 수학적인 상관 관계를 이용하여 왜곡을 보정하는 방법으로서 평면 전체를 변환시키는 평면기하보정이 주로 사용되어 왔으나, 이것은 지형 변화가 큰 지역의 왜곡을 제대로 보정하지 못하는 단점이 있다. 본 논문에서는 이를 보완하기 위해 TIN단위의 기하보정 방법을 제안하고 평면기하보정 방법과 결과를 비교하며, 지상기준점과의 상관성을 분석한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.40-44
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• 2002

Precision correction is the process of geometrically aligning images to a reference coordinate system using GCPs(Ground Control Points). Many applications of remote sensing data, such as change detection, mapping and environmental monitoring, rely on the accuracy of precision correction. However it is a very time consuming and laborious process. It requires GCP collection, the identification of image points and their corresponding reference coordinates. At typical satellite ground stations, GCP collection requires most of man-powers in processing satellite images. A method of automatic registration of satellite images is demanding. In this paper, we propose a new algorithm for automatic precision correction by GCP chips and RANSAC(Random Sample Consensus). The algorithm is divided into two major steps. The first one is the automated generation of ground control points. An automated stereo matching based on normalized cross correlation will be used. We have improved the accuracy of stereo matching by determining the size and shape of match windows according to incidence angle and scene orientation from ancillary data. The second one is the robust estimation of mapping function from control points. We used the RANSAC algorithm for this step and effectively removed the outliers of matching results. We carried out experiments with SPOT images over three test sites which were taken at different time and look-angle with each other. Left image was used to select UP chipsets and right image to match against GCP chipsets and perform automatic registration. In result, we could show that our approach of automated matching and robust estimation worked well for automated registration.

• 대한공간정보학회지
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• 제22권4호
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• pp.127-133
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• 2014

본 연구는 2007년 이래 국토지리정보원에서 제공하고 있는 Network-RTK(VRS) 측량을 항공사진도화에 필요한 지상기준점측량에 적용하기 위하여 그 정확도를 검증하는데 목적이 있다. 세계측지계(ITRF2000)에 근거하여 국가기준점을 고정한 상대측위방식 Static GNSS 측량으로 지상기준점(GCP)을 측정하여 이를 정확값으로 간주하였다. 2종의 Network-RTK 수신기를 이용하여 동일 지상기준점의 위치를 구한 후, 좌표변환과 지오이드 모델을 적용하여 세계측지계 좌표로 변환하였다. Static GNSS 측량과 2종의 Network-RTK 측량에 의한 측정값을 비교한 결과, GCP 위치좌표의 평균제곱근오차는 평면에서 ${\pm}2.0cm$, 표고에서 ${\pm}7.0cm$ 이었다. 즉, 지상기준점측량에서 GPS 수신기 1세트로 짧은 시간 관측할 수 있는 Network-RTK 측량은 GNSS 수신기 2세트 이상을 필요로 하는 RTK 측량이나 GNSS 수신기 2세트 이상으로 장시간의 관측이 필요한 Static GNSS 측량의 실용적인 대안임을 알 수 있었다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2007년도 춘계학술발표회 논문집
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• pp.295-299
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• 2007

Today, ubiquitous technology (e.g. computers or networked devices pervade everywhere we are) has enlarged by great advancement of information and communication technologies. If ubiquitous technologies is applied to, innovation of spatial information technology is expected. traditional spatial information technologies such as survey, GIS, GPS, LBS, and RS and ubiquitous technology gradual1y have been converged. The aim of this study is to create shared visions in spatial information technologies by scenario based roadmapping. So, we surveyed the state of the art in main spatial information technologies, market status and patent map. Consequently, prospects of spatial information technologies is suggested. The aim of 1st and 2nd NGIS project focused on map supplier was to develop digital map(e.g. framework data, various thematic map). As a result, the best technology of digital mapping is achieved in the world. But, there is not enough to develop GIS and LBS solution. Current market in GIS S/W and Telematics is about 384billon won and 250billion won. a patent is applied in the order, like a USA(1571case, 47%), Japan(883case, 26%), EU(478case, 14%), Korea(446case, 13%). In the future, spatial information technology fused on ubiquitous technology will be focused on user's demand and developing convenience context. The developing target will be realtime monitoring of 3D spatial data based on high resolution coordinate system, sharing and supplying multi-sensor data considered users demand, location service by ubiquitous technologies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제14권1호
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• pp.323-343
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• 2020

With the rapid development of computer and communication techniques, copyright protection of vector geographic data has attracted considerable research attention because of the high cost of such data. A novel adaptive watermark detection algorithm is proposed for vector geographic data that can be used to qualitatively analyze the robustness of watermarks against data addition attacks. First, a watermark was embedded into the vertex coordinates based on coordinate mapping and quantization. Second, the adaptive watermark detection model, which is capable of calculating the detection threshold, false positive error (FPE) and false negative error (FNE), was established, and the characteristics of the adaptive watermark detection algorithm were analyzed. Finally, experiments were conducted on several real-world vector maps to show the usability and robustness of the proposed algorithm.

• 패션비즈니스
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• 제7권2호
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• pp.143-155
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• 2003

The purpose of this study were to investigate 1) Values placed upon born hereditary appearance and a made up appearance, 2)examined for points of body and clothing and 3)discrepancy in opinions about Coordination system of 3D Virtual Model This study chose qualitative research approach in-depth interviews were from December 12, 2002, to February 20, 2003. The subjects of the study were 12 women aged in twenties 12 women aged over forty. The results of this study were as follows. 1. Women aged in their twenties defined appearance as follows. there are important a made up appearance, Appearance is looking at point of view from body shape to face, makeup, hair style, body image, cosmetic surgery, clothing and is looking at the whole point of view from hair to tiptoe. This seems to include attitude, personality, behavior, images, and feeling. 2. Regarding body image Women aged in their twenties prefer a slender figure. Women aged in their twenties exerts all possible efforts to have an attractive body through dress well. 3. Regarding body image Women aged in their twenties prefer coordinate to system of 3D virtual model.

• 로봇학회논문지
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• 제7권1호
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• pp.29-34
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• 2012

This paper suggests a new observation model for Extended Kalman Filter based Simultaneous Localization and Mapping (EKF-SLAM). Since the EKF framework linearizes non-linear functions around the current estimate, the conventional line model has large linearization errors when a mobile robot locates faraway from its initial position. On the other hand, the model that we propose yields less linearization error with respect to the landmark position and thus suitable in a large-scale environment. To achieve it, we build up a three-dimensional space by adding a virtual axis to the robot's two-dimensional coordinate system and extract a plane by using a detected line on the two-dimensional space and the virtual axis. Since Jacobian matrix with respect to the landmark position has small value, we can estimate the position of landmarks better than the conventional line model. The simulation results verify that the new model yields less linearization errors than the conventional line model.

• 한국측량학회지
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• 제14권2호
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• pp.119-126
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• 1996

TM투영은 일반적으로 측량 또는 지도제작에서 가장 널리 사용되고 있는 투영법이다. 그러나 복잡한 수학적 계산식으로 인하여 원리의 이해와 사용에 어려움이 있으며 또한 실제적인 적용에 있어서 계산공식을 어떻게 사용하며 어떻한 계수를 사용하는가에 따라 그 결과도 크게 달라진다. 이 연구에서는 무한급수로 전개되는 TM투영 계산공식을 급수 항의 수효에 따라 4가지 종류로 구분하고 이들이 최종 좌표에 미치는 영향에 대하여 고찰하였으며, 특히 좌표변환과정에서 필수적으로 사용되는 원주율$(\pi)$의 유효숫자가 미치는 영향에 대해서도 고찰하였다. 연구결과 경도차의 크기에 따라 오차도 달라져서, 경도차 $1^\circ$에서는 거의 변화가 없었으나 $2^\circ$와 $3^\circ$등 경도차가 클수록 더 큰 오차가 발생하였다. 또한 위도변화에 대해서는 위도가 낮을수록 더 큰 오차가 발생되었다. 특히, $\pi$값의 사용에서는 지상 1 mm의 정밀도를 유지하기 위해서는 소수 13자리까지 사용하여야 함을 알 수 있었다.

• 한국산학기술학회논문지
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• 제10권4호
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• pp.785-794
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• 2009

워게임모델에서 가상환경격자정보에 관한 개선과 구축기법을 연구하였다. 가상환경자료는 지상, 해상, 공중으로 구분하여 관리 및 운용한다. 가상환경자료는 지리정보와 지형형태정보로 구축 및 관리한다. 지리정보는 격자(Grid) 형태로서 격자위치좌표와 수심을 파일로 관리한다. 그 격자정보파일의 수심값을 이동가능대표값(GCV)으로 개선하고, 조석차가 심한지역에 대해서 동적가상환경구축기법을 제안하였다. 제안된 시스템 의 구현 및 시험을 통하여 동적 가상환경을 워게임모델에 적용이 가능하다는 것을 알 수 있었다.

• Structural Engineering and Mechanics
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• 제25권2호
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• pp.161-180
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• 2007

A first endeavor is made to exploit the differential quadrature method (DQM) as a simple, accurate, and computationally efficient numerical tool for the large deformation analysis of thin laminated composite skew plates, which has very strong singularity at the obtuse vertex. The geometrical nonlinearity is modeled by using Green's strain and von Karman assumption. A recently developed DQ methodology is used to exactly implement the multiple boundary conditions at the edges of skew plates, which is a major draw back of conventional DQM. Using oblique coordinate system and the DQ methodology, a mapping-DQ discretization rule is developed to simultaneously transform and discretize the equilibrium equations and the related boundary conditions. The effects of skew angle, aspect ratio and different types of boundary conditions on the convergence and accuracy of the presented method are studied. Comparing the results with the available results from other numerical or analytical methods, it is shown that accurate results are obtained even when using only small number of grid points. Finally, numerical results for large deflection behavior of antisymmetric cross ply skew plates with different geometrical parameters and boundary conditions are presented.