• Title/Summary/Keyword: Point Landmark

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Fast landmark matching algorithm using moving guide-line image

  • Seo Seok-Bae;Kang Chi-Ho;Ahn Sang-Il;Choi Hae-Jin
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.208-211
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    • 2004
  • Landmark matching is one of an important algorithm for navigation of satellite images. This paper proposes a fast landmark matching algorithm using a MGLI (Moving Guide-Line Image). For searching the matched point between the landmark chip and a part of image, correlation matrix is used generally, but the full-sized correlation matrix has a drawback requiring plenty of time for matching point calculation. MGLI includes thick lines for fast calculation of correlation matrix. In the MGLI, width of the thick lines should be determined by satellite position changes and navigation error range. For the fast landmark matching, the MGLI provides guided line for a landmark chip we want to match, so that the proposed method should reduce candidate areas for correlation matrix calculation. This paper will show how much time is reduced in the proposed fast landmark matching algorithm compared to general ones.

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A Study on the Landmark Experience for Anchorage in Pusan port (부산항에 있어서 묘박을 위한 랜드마크 체험에 관한 연구)

  • 이동화;강영조
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.4
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    • pp.59-64
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    • 1999
  • This study is about gaining orientation through anchorage act of a group of ferryman. In addition, a point acquisition and character of landmark that is closely realated to a point acquisition would be clarified by studying the form of configuration of the earth and object which is used landmark for anchorage. There are 13 anchorage points in the north part of Pusan harbor. 12 anchorage points are used to anchor. A ferryman let a ship which is temporarily anchoring move safely and speedily at the anchorage point. At that time, he uses landmarks by a technique of Overlay View. Between landmarks and viewer would be formed exquisite location combination. A mountain peak, a peak of island, nature configuration of land such as intermitent rock and location, size and form of buildings or structures of a city were variously appeared as landscape elements which were used landmarks. Looking at conditions to be easily captured as a target object, 1. A particular point of a mountain ridge line which was not shield by buildings. 2. In case objects have similar form, the building which was located in the front or the highest. 3. In case of a singular object, whatever there is physical elements, that would be a target object. Through this study a configuration of the ground such as a mountain peak which is become the background of harbor landscape is very important element to find anchorage point in configuration of the ground and object. So, the continuous preservation of the contour line of mountain is needed to do safe and effective anchorage act.

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Surface Mapping of Masseter for Botulinum Toxin Injection (교근에서 보툴리눔 독소 주사점의 표지화)

  • Kim, Jun Hyung;Lee, Min Jae;Kim, Hyun Ji;Son, Dae Gu;Han, Ki Hwan;Lee, So Young;Lim, Jung Guen;Choi, In Jang
    • Archives of Plastic Surgery
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    • v.32 no.3
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    • pp.311-313
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    • 2005
  • Generally, many Asian women tend to dislike the square jaw, as they believe it makes the face look wider, giving a stubborn and strong impression. Contouring of the mandible is therefore a relatively common aesthetic procedure among Asians. These days, the use of botulinum toxin for contouring of the lower face offer simple alternative to surgery. Motor point, which is the site over a muscle where its contraction may be elicited by a minimal intensity short duration electrical stimulus, is the optimal injection point of botulinum toxin. Study was undertaken to identify the location of motor point of the masseter muscle and the skin surface landmark. First, the thickest point of the masseter muscle was inspected through palpation and inspection by 3 different individual plastic surgeons and then compound muscle action potentials(CMAPs) of masseter muscle in 15 health volunteers were recorded using EMG. For the localization of the measured points, line between lateral canthus to the mandibular angle was used. Location of motor points were mapped to skin surface from lateral canthus in a percentage of the distance along the landmark line and in distance in millimeters. The clinical injection point was located at 71.69 percentile and 7.3 mm of the landmark line. The motor point test was located at 72.54 percentile and 7.1 mm of the landmark line. The depth of motor point was 16mm. There was no statistically significant difference between the clinical injection point and the motor point. We conclude that surface mapping of motor point of the masseter muscle would increase accessibility and accuracy in botulinum toxin injection for contouring of the lower face.

Detection of Landmark Spots for Spot Matching in 2DGE (2차원 전기영동 영상의 스팟 정합을 위한 Landmark 스팟쌍의 검출)

  • Han, Chan-Myeong;Suk, Soo-Young;Yoon, Young-Woo
    • Journal of the Korean Society of Industry Convergence
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    • v.14 no.3
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    • pp.105-111
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    • 2011
  • Landmark Spots in 2D gel electrophoresis are used in many methods of 2DEG spot matching. Landmark Spots are obtained manually and it is a bottle neck in the entire protein analysis process. Automated landmark spots detection is a very crucial topic in processing a massive amount of 2DGE data. In this paper, Automated landmark spot detection is proposed using point pattern matching and graph theory. Neighbor spots are defined by a graph theory to use and only a centered spot and its neighbor spots are considered for spot matching. Normalized Hausdorff distance is introduced as a criterion for measuring degree of similarity. In the conclusion, the method proposed in this paper can get about 50% of the total spot pairs and the accuracy rate is almost 100%, which the requirements of landmark spots are fully satisfied.

Generation and Detection of Cranial Landmark

  • Heo, Suwoong;Kang, Jiwoo;Kim, Yong Oock;Lee, Sanghoon
    • Journal of International Society for Simulation Surgery
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    • v.2 no.1
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    • pp.26-32
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    • 2015
  • Purpose When a surgeon examines the morphology of skull of patient, locations of craniometric landmarks of 3D computed tomography(CT) volume are one of the most important information for surgical purpose. The locations of craniometric landmarks can be found manually by surgeon from the 3D rendered volume or 2D sagittal, axial, and coronal slices which are taken by CT. Since there are many landmarks on the skull, finding these manually is time-consuming, exhaustive, and occasionally inexact. These inefficiencies raise a demand for a automatic localization technique for craniometric landmark points. So in this paper, we propose a novel method through which we can automatically find these landmark points, which are useful for surgical purpose. Materials and Methods At first, we align the experimental data (CT volumes) using Frankfurt Horizontal Plane (FHP) and Mid Sagittal Plane(MSP) which are defined by 3 and 2 cranial landmark points each. The target landmark of our experiment is the anterior nasal spine. Prior to constructing a statistical cubic model which would be used for detecting the location of the landmark from a given CT volume, reference points for the anterior nasal spine were manually chosen by a surgeon from several CT volume sets. The statistical cubic model is constructed by calculating weighted intensity means of these CT sets around the reference points. By finding the location where similarity function (squared difference function) has the minimal value with this model, the location of the landmark can be found from any given CT volume. Results In this paper, we used 5 CT volumes to construct the statistical cubic model. The 20 CT volumes including the volumes, which were used to construct the model, were used for testing. The range of age of subjects is up to 2 years (24 months) old. The found points of each data are almost close to the reference point which were manually chosen by surgeon. Also it has been seen that the similarity function always has the global minimum at the detection point. Conclusion Through the experiment, we have seen the proposed method shows the outstanding performance in searching the landmark point. This algorithm would make surgeons efficiently work with morphological informations of skull. We also expect the potential of our algorithm for searching the anatomic landmarks not only cranial landmarks.

Fast Algorithm for Location Determination of Mobile Robot: Vertical Line to Point Correspondences (이동로보트의 실시간 위치결정을 위한 수직선과 점 대응 알고리즘)

  • 김재희;조형석
    • 제어로봇시스템학회:학술대회논문집
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    • 1990.10a
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    • pp.716-721
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    • 1990
  • It is one of the essential task to determine the absolute location of mobile robot during its navigation. In this paper we propose an algorithm to calculate the distance and orientation of camera from landmark through the visual image of stripe typed landmark. Exact closed form solution of camera location is obtained with the correspondences from vertical line on mark plane to the intersection point of projected line with horizontal axis of image plane. It needs only one line image information, so that location determination can be processed in real time.

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Analysis on Occlusion Problem of Landmark-based Homing Navigation Methods (랜드마크 기반 귀소 내비게이션 알고리즘의 가림 현상 분석 및 비교)

  • Yu, Seung-Eun;Kim, Dae-Eun
    • Journal of Institute of Control, Robotics and Systems
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    • v.17 no.6
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    • pp.596-601
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    • 2011
  • Autonomous navigating algorithms for mobile robots have been proved to be a difficult task. Based on the excellent homing performance shown by many insects, bio-inspired navigation algorithms for robotic experiments have been widely researched and applied to the design of navigational strategies for mobile robots. In this paper, among them, we analyze two simple landmark navigation methods their strengths and limits. We investigate the effect of the occlusion problem mainly, which is an important yet tough problem in many landmark navigation algorithms. In the point of view of the error of homing vector and the performance of the homing paths in the environment with artificial occlusions, we investigate the effect of occlusion problem in both methods in order to further study on solutions.

Landmarks in The Skull for Stereotactic Radiotherapy

  • Hiroki, Ohtani;Toraji, Irifune;Etsuo, Kunieda;Hidetoshi, Saitoh;Masahiro, Fukushi;Tsuguhisa, Katoh
    • Proceedings of the Korean Society of Medical Physics Conference
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    • 2002.09a
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    • pp.144-145
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    • 2002
  • Stereotactic radiotherapy is required to irradiate a small tumor accurately. The radiotherapy showing improves when making an accidental error little boundlessly. It is performed according to treatment planning that is established by the outside landmark of head. At present, when stereotactic radiotherapy for a head is done, the Leksell Flame is fixed on the head, and positioning based on the point and so on which it is in that fixed implement is performed. However, there are problems on the method done at present in the point such as reappearance when the fractionated irradiation method in which the Leksell Flame is removed and installed at every treatment is done because there are landmarks outside the head. Landmarks in the skull were decided, and that precision was examined for the purpose of the improvement of the radiation therapeutic gain. Linac-graphy with longitudinal and lateral view were taken with 6 MV photon beams. A distance to base point inside the skull, each film measured the angle from a center of the small irradiation field, and comparison was done. From the results, a large accidental error wasn't seen as a result of the measurement by every film. Stereotactic radiotherapy for a head treatment had an accidental error of about several millimeters when treatment positioning was done. Therefore, it was thought that there was no problem about an accidental error to arise by putting a landmark in the skull. And, because an accidental error was easy to discover, we thought that modification could be done easily. It was suggested that a landmark in the skull on thus study were useful for improvement of stereotactic radiotherapy.

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Analysis on the Differences of Point of View between Architect and Urban Planner on the Evaluation of International Urban Design Competition (국제설계경기 평가에서 건축가와 도시계획가의 관점차이 분석)

  • Lee, Sangho;Leem, Yountaik;Jeon, Jong Nyoung
    • The Journal of the Korea Contents Association
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    • v.13 no.7
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    • pp.417-431
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    • 2013
  • During the development process of mega-project, individual buildings including skyscrapers are built following the master plan. It is not a difficult thing to see the gap of standpoint between the urban planners and architects on the project. This study aims to analyze the difference between architect and urban planner's point of view in evaluating international design competition works which the internationally distinguished honorable design companies(SOM, Jerde Partnership, Studio Daniel Libeskind, Foster+Partners and Asymptote Architecture) submitted as the ideas of Yongsan International Business District Design. Furthermore, we made an attempt to quantify the weight of each factors of urban design by each group. Architect and urban planner's viewpoint were revealed with seven architects and seven urban planners evaluating the international design competition works through AHP(Analytical Hierarchy Process). AHP structure was made of two step hierarchy in terms of Master Plan and Landmark Tower. Eight evaluation criteria were set up such as the concept, land use, transportation, feasibility of Master Plan and the concept, location, functional efficiency and aesthetic beauty of Landmark Tower. Results show that Architect have different point of view from that of urban planner. While the architect's weight of evaluation criteria is on the Landmark Tower(0.505), urban planner's weight is on Master Plan(0.642). Feasibility, the location of Landmark Tower and land-use are very important evaluation criteria to architect and urban planner in common. Functional efficiency of Landmark Tower is in architect's favour and transportation is in urban planner.

Development of an Algorithm for Automatic Extraction of Lower Body Landmarks Using Grasshopper Programming Language (Grasshopper 프로그래밍 기반 3D 인체형상의 하반신 기준점 자동탐색 알고리즘 설계)

  • Eun Joo Ryu;Hwa Kyung Song
    • Journal of the Korean Society of Clothing and Textiles
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    • v.47 no.1
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    • pp.171-190
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    • 2023
  • This study aims to develop algorithms for automatic extraction landmarks from the lower body of women aged 20-54 using the Grasshopper programming language, based on 3D scan data in the 8th SizeKorea dataset. First, 11 landmarks were defined using the morphological features of 3D body surfaces and clothing applications, from which automatic landmark extraction algorithms were developed. To verify the accuracy of the algorithm, this study developed an additional algorithm that could automatically measure 16 items, and algorithm-derived measurements and SizeKorea measurements were compared using paired t-test analysis. The statistical differences between the scan-derived measurements and the SizeKorea measurements were compared, with an allowable tolerance of ISO 20685-1:2018. This study found that the algorithm successfully identified most items except for the crotch point and gluteal fold point. In the case of landmarks with significant differences, the algorithms were modified. This study was significant because scan editing, landmark search, and measurement extraction were successfully performed in one interface, and the developed algorithm has a high efficiency and strong adaptability.