• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.7
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• pp.157-165
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• 1989

To recover three dimensional information in Shape from Texture, the distorting effects of projection must be distinguished from properties of the texture on which the distortion acts. In this paper, we show an approximated maximum likelihood estimation method in which we find surface orientation of the visible surface (hemisphere) in gaussian sphere using local analysis of the texture. In addition, assuming that an orthogonal projection and a circle is an image formation system and a texel (texture element) respectively, we drive the surface orientation from the distribution of variation by means of orthogonal projection of a tangent direction which exists regularly in the arc length of a circle. We present the orientation parameters of textured surface with slant and tilt in gradient space, and also the surface normal of the resulted surface orientationas as needle map. This algorithm is applied to geographic contour (artificially generated chejudo) and synthetic texture.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.4
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• pp.271-277
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• 2018

Generating an epipolar image which is removed a y-parallax from an original image is an essential technique for creating a 3D stereoscopic model or producing a map. In epipolar image production, there is a method of generating epipolar images by estimating the relative orientation parameters after matching the extracted distinct points in two images and a method of generating epipolar images by using the baseline and rotation angles of the two images after determining the exterior orientation parameters In this study, it was proposed a methodology to generate epipolar images using direction cosine in the exterior orientation parameters of the input images, and a method to use the transformation matrix for easy calculation when converting from the original image to the epipolar image. The applicability of the proposed methodology was evaluated by using images taken from the fixed wing and rotary wing drones. As a result, it was found that epipolar images were generated regardless of the type of drones.

• Journal of Cadastre & Land InformatiX
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• v.48 no.1
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• pp.111-121
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• 2018

RIn this research, digital elevation models, true-ortho image and 3-dimensional digital complied data was generated and evaluated using unmanned aircraft vehicle stereoscopic images by applying photogrammetric principles. In order to implement stereoscopic vision, digital Photogrammetric Workstation should be used necessarily. For conducting this, in this study GEOMAPPER 1.0 is used. That was developed by the Ministry of Trade, Industry and Energy. To realize stereoscopic vision using two overlapping images of the unmanned aerial vehicle, the interior and exterior orientation parameters should be calculated. Especially lens distortion of non-metric camera must be accurately compensated for stereoscope. In this work. photogrammetric orientation process was conducted using commercial Software, PhotoScan 1.4. Fixed wing KRobotics KD-2 was used for the acquisition of UAV images. True-ortho photo was generated and digital topographic map was partially produced. Finally, we presented error analysis on the generated digital complied map. As the results, it is confirmed that the production of digital terrain map with a scale 1:2,500~1:3,000 is available using stereoscope method.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.37 no.6
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• pp.555-562
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• 2019

This paper presents soil deformation measurement in model chamber based on photogrammetry. We created an aluminum framed acrylic model chamber with soil inside and applied photogrammetry to measure soil deformation caused by loading tests. The soil consists of 40% black and 60% regular sand to create image contrast in soil images. In preprocessing, the self camera calibration was carried out for IOPs (Interior Orientation Parameters), followed by the space resection to estimate EOPs (Exterior Orientation Parameters) using control points located along the aluminum frame. Image matching was applied to measure the soil displacement. We tested different matching window sizes and the effect of image smoothing. Experimental results showed that 65x65 pixels of window size produced better soil deformation map and the image smoothing was useful to suppress the matching outliers. In conclusion, photogrammetry was able to efficiently generated soil deformation map.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.2042-2047
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• 2005

Many service robots which is interacting with human at home and in buildings have been developed. Few of them are shown in of the United States and of Japan. These robots are supposed to have a powerful indoor navigation performance in places where human beings live and work. The overall capability of service robots to move around in this environment is called environment correspondence, in which localization problem to find the accurate position and orientation is the most critical problem. While users set up a proper or a best environment for industrial robots, but for services robots at home and in buildings, it is very difficult to change the environment for robots. The expanded workspace due to mobility is difficult to be covered by means of those used for industrial robots because the cost increases and human beings do not want their environment to be changed for robots. This fact has made many researchers study efficient and effective environment correspondence problems. Among these problems, localization is the most difficult. Goal of localization study includes (1) Accurate detection of position and orientation (2) Minimum cost of the additional devices (3) Minimum change of human environment. In this study, as a solution of the above, we propose "Artificial Stars" which are attached on room ceiling as landmarks. In addition, we solve an adoption problem raised when a robot is delivered to a customer site and before it can perform its full navigation capability. We call this as "Initialization Problem" of service robots. We solve the initialization problem for both cases of environment with the map and without map. The proposed system is experimented and has shown how well it handles the initialization problem.

• Economic and Environmental Geology
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• v.47 no.2
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• pp.121-131
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• 2014

The stability of rock slope is mainly controlled by the orientation and shear strength of discontinuties in rock mass. Therefore, in kinematic analysis, the orientation of the combination of discontinuities and slope face is examined to determine if certain modes of failure can be occurred. In previous kinematic analysis, a representative orientation of the slope face and mean orientation of discontinuity set were used as input parameters. However, since the orientations of slope face varies according to locations of measurement, the representative slope face orientation could cause misunderstanding for kinematic instability. In addition, since the orientations of each discontinuity are scattered in the same discontinuity set, there is the possibility that uncertainties are involved in the procedure of kinematic analysis. Therefore, in this study, the detailed digital topographic map was used to obtain the orientation of slope face. In addition, the probabilistic analysis approach was utilized to deal properly with the uncertainties in discontinuity orientation. The proposed approach was applied to steep slopes in mountain road located in Baehuryeong, Chunncheon city, Gangwon-Do. The analysis results obtained from the deterministic and probabilistic analysis were compared to check the feasibility of proposed the analysis.

• The Journal of the Korea Contents Association
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• v.8 no.3
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• pp.270-278
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• 2008

This study : An analysis of position accuracy of topography according to using LiDAR data, aerial photo and digital map for a study area was conducted. The study area was selected in Hadan area, Sahagu, Busan aerial LiDAR data and aerial photo in the scales of 1:20,000, which are high tech surveying ways were used. The final digital orthoimage according to orientation process for each image and image resampling was producted. Using it, a checkpoint was chosen, information about the checkpoints selected was extracted, a coordinate of Horizontal Position through the screen digitizing was also extracted. Both the coordinates of LiDAR data and aerial photo using digital map in the scales of 1:20,000 announced to the public from NGII(National Geographic Information Institute) were gradually compared and analyzed. Based on the digital map, as a result of being both compared and analyzed, it has shown to us that horizontal position of aerial photo is more accurate than that of aerial LiDAR surveying (RMSE-building x:24cm, y:26cm).

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.9C
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• pp.860-867
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• 2003

In this paper, an efficient core point detection method using orientation pattern labeling is proposed in fingerprint image. The core point, which is one of the singular points in fingerprint image, is used as the reference point in the most fingerprint recognizing system. Therefore, the detection of the core point is the most essential step of the fingerprint recognizing system, it can affect in the whole system performance. The proposed method could detect the position of the core point by applying the labeling method for the directional pattern which is come from the distribution of the ridges in fingerprint image and applying detailed algorithms for the decision of the core point's position. The simulation result of proposed method is better than the result of Poincare index method and the sine map method in executing time and detecting rate. Especially, the Poincare index method can't detect the core point in the detection of the arch type and the sine map method takes too much times for executing. But the proposed method can overcome these problems.

• Journal of Microbiology and Biotechnology
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• v.9 no.4
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• pp.457-463
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• 1999

The physical map of bacteriophage $\PhiFC1$ DNA was constructed with the restriction endonucleases SalI, BamHI, EcoRI, XbaI, and AvaI. The 40.5-kb DNA restriction map is shown to be circularly permuted representing the headful packaging mechanism of the phage. The DNA restriction fragments containing the packaging initiation site(pac) was localized on the restriction map and the nucleotide sequences of the region were analyzed. Four open reading frames (ORFs), following one another with the same orientation, were found at the region. The 2nd ORF (ORF-ts) has significant amino acid sequence homologies to the previously known terminase small subunits of other bacteriophages. The putative terminase small subunit gene has a presumptive NTP-hydrolysis motif and a helix-turn-helix motif. The cleavage site for the first round of packaging was found to be located at the coding sequence of the putative terminase small subunit gene. The fourth ORF, even if partially sequenced, has a good amino acid sequence homology to the portal vertex proteins of other bacteriophages representing the evolutionarily conserved arrangements of genes near the pac site of this bacteriophage, $\PhiFC1$.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.17 no.5
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• pp.1339-1355
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• 2023

Localization is a hot research spot for many areas, especially in the mobile robot field. Due to the weak signal of the global positioning system (GPS), the alternative schemes in an indoor environment include wireless signal transmitting and receiving solutions, laser rangefinder to build a map followed by a re-localization stage and visual positioning methods, etc. Among all wireless signal positioning techniques, Wi-Fi is the most common one. Wi-Fi access points are installed in most indoor areas of human activities, and smart devices equipped with Wi-Fi modules can be seen everywhere. However, the localization of a mobile robot using a Wi-Fi scheme usually lacks orientation information. Besides, the distance error is large because of indoor signal interference. Another research direction that mainly refers to laser sensors is to actively detect the environment and achieve positioning. An occupancy grid map is built by using the simultaneous localization and mapping (SLAM) method when the mobile robot enters the indoor environment for the first time. When the robot enters the environment again, it can localize itself according to the known map. Nevertheless, this scheme only works effectively based on the prerequisite that those areas have salient geometrical features. If the areas have similar scanning structures, such as a long corridor or similar rooms, the traditional methods always fail. To address the weakness of the above two methods, this work proposes a coarse-to-fine paradigm and an improved localization algorithm that utilizes Wi-Fi to assist the robot localization in a geometrically similar environment. Firstly, a grid map is built by using laser SLAM. Secondly, a fingerprint database is built in the offline phase. Then, the RSSI values are achieved in the localization stage to get a coarse localization. Finally, an improved particle filter method based on the Wi-Fi signal values is proposed to realize a fine localization. Experimental results show that our approach is effective and robust for both global localization and the kidnapped robot problem. The localization success rate reaches 97.33%, while the traditional method always fails.