• Title/Summary/Keyword: Landmark extraction

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Extraction of Landmarks Using Building Attribute Data for Pedestrian Navigation Service (보행자 내비게이션 서비스를 위한 건물 속성정보를 이용한 랜드마크 추출)

  • Kim, Jinhyeong;Kim, Jiyoung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.1
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    • pp.203-215
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    • 2017
  • Recently, interest in Pedestrian Navigation Service (PNS) is being increased due to the diffusion of smart phone and the improvement of location determination technology and it is efficient to use landmarks in route guidance for pedestrians due to the characteristics of pedestrians' movement and success rate of path finding. Accordingly, researches on extracting landmarks have been progressed. However, preceding researches have a limit that they only considered the difference between buildings and did not consider visual attention of maps in display of PNS. This study improves this problem by defining building attributes as local variable and global variable. Local variables reflect the saliency of buildings by representing the difference between buildings and global variables reflects the visual attention by representing the inherent characteristics of buildings. Also, this study considers the connectivity of network and solves the overlapping problem of landmark candidate groups by network voronoi diagram. To extract landmarks, we defined building attribute data based on preceding researches. Next, we selected a choice point for pedestrians in pedestrian network data, and determined landmark candidate groups at each choice point. Building attribute data were calculated in the extracted landmark candidate groups and finally landmarks were extracted by principal component analysis. We applied the proposed method to a part of Gwanak-gu, Seoul and this study evaluated the extracted landmarks by making a comparison with labels and landmarks used by portal sites such as the NAVER and the DAUM. In conclusion, 132 landmarks (60.3%) among 219 landmarks of the NAVER and the DAUM were extracted by the proposed method and we confirmed that 228 landmarks which there are not labels or landmarks in the NAVER and the DAUM were helpful to determine a change of direction in path finding of local level.

Changes in soft tissue chin resulting from premolar extraction and incisor retraction in adult female patients (성인 여성에서 소구치 발치와 전치부 후방 견인에 따른 이부 연조직 변화)

  • Kim, Yang-Hee;Son, Woo-Sung
    • The korean journal of orthodontics
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    • v.31 no.5 s.88
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    • pp.535-548
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    • 2001
  • The purpose of this study was to evaluate changes in soft tissue chin thickness and to investigate correlations between hard and soft tissues measurements after orthodontic treatment conducted by premolars extraction and incisor retraction. The sample consisted of 35 female adults with Angle classification class I or class II division 1 malocclusion. Using lateral cephalometric radiographs taken before and after treatment, hard and soft tissue structures were measured and reproducible six landmark on soft chin tissue were used to locate the various points of soft tissue contour of the chin. The res에ts were as follows : 1. There were signigicant correlations between pretreatment B-B', Pm-Pm' and pretreatment vortical skeletal measurements such as $MP{\perp}HP,\;MP{\perp}PP$, ALFH and between a-a', b-b', Me-Me' and measurements of sym-physeal morphology such as SL, SW, PL. 2. There were significant decreases at B-B', Pm-Pm' and significant increases at a-a', b-b' between pre-and posttreatment mea surements. 3. There were significant correlations among soft tissues changes and hard tissue changes except for changes at B-B' and the range of correlation coefficient was about 0.3-0.4. 4. There were significant differences at ${\Delta}UI-VP,\;LI{\perp}, and B-B' measurements between subgroups divided by posttreatment Pog-Pog' changes. 5. There were significant differences at ${\Delta}overbite,\;NPog{\perp}HP,\;and\;Me-Me'$ measurements between subgroups divided by posttreatment Me-Me' changes.

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Classification and Characteristics of Neck-base Shape of Korean Females in Their Twenties (20대 여성의 목밑둘레 형태 유형화 및 특징)

  • Hwang Keun Young;Nam Yun Ja;Park Jae Kyung
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.3_4 s.141
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    • pp.502-510
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    • 2005
  • The purpose of this study is to identify neck shapes of women by classifying their neck-base types according to the shapes of neck and analyzing the characteristics of each type. The subjects were 58 women $18\~24$ years of age. Their body were measured directly and indirectly by using camera, 3-dimensional body scanner. The anthropometric measurements were composed of 17 items. They were measured during the months of October in 2001 The results and discussions of this study are as follows. There were three kinds of neck-base type. The first type was slant from the back neck-base to the side neck-base, and slant from the side neck-base to the front neck-base. The second type was gentle from the back neck-base to the side neck-base, and gentle from the side nect-base to the front neck-base. finally, the third type was gentle from the back neck-base to the side neck-base, and slant from the side neck-base to the front neck-base. Hopefully, understanding the shapes of neck and characteristics of each neck-base type will help to suggest computer assisted neck-base's landmark identification algorithms and measurement extraction methods from three-dimensional body scan data.

Door Recognition using Visual Fuzzy System in Indoor Environments (시각 퍼지 시스템을 이용한 실내 문 인식)

  • Yi, Chu-Ho;Lee, Sang-Heon;Jeong, Seung-Do;Suh, Il-Hong;Choi, Byung-Uk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.1
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    • pp.73-82
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    • 2010
  • Door is an important object to understand given environment and it could be used to distinguish with corridors and rooms. Doors are widely used natural landmark in mobile robotics for localization and navigation. However, almost algorithm for door recognition with camera is difficult real-time application because feature extraction and matching have heavy computation complexity. This paper proposes a method to recognize a door in corridor. First, we extract distinguished lines which have high possibility to comprise of door using Hough transformation. Then, we detect candidate of door region by applying previously extracted lines to first-stage visual fuzzy system. Finally, door regions are determined by verifying knob region in candidate of door region suing second-stage visual fuzzy system.

A Bayesian Inference Model for Landmarks Detection on Mobile Devices (모바일 디바이스 상에서의 특이성 탐지를 위한 베이지안 추론 모델)

  • Hwang, Keum-Sung;Cho, Sung-Bae;Lea, Jong-Ho
    • Journal of KIISE:Computing Practices and Letters
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    • v.13 no.1
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    • pp.35-45
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    • 2007
  • The log data collected from mobile devices contains diverse meaningful and practical personal information. However, this information is usually ignored because of its limitation of memory capacity, computation power and analysis. We propose a novel method that detects landmarks of meaningful information for users by analyzing the log data in distributed modules to overcome the problems of mobile environment. The proposed method adopts Bayesian probabilistic approach to enhance the inference accuracy under the uncertain environments. The new cooperative modularization technique divides Bayesian network into modules to compute efficiently with limited resources. Experiments with artificial data and real data indicate that the result with artificial data is amount to about 84% precision rate and about 76% recall rate, and that including partial matching with real data is about 89% hitting rate.

Knowledge Domain and Emerging Trends of Intelligent Green Building and Smart City - A Visual Analysis Using CiteSpace

  • Li, Hongyang;Dai, Mingjie
    • International conference on construction engineering and project management
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    • 2017.10a
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    • pp.24-31
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    • 2017
  • As the concept of sustainability becomes more and more popular, a large amount of literature have been recorded recently on intelligent green building and smart city (IGB&SC). It is therefore needed to systematically analyse the existing knowledge structure as well as the future new development of this domain through the identification of the thematic trends, landmark articles, typical keywords together with co-operative researchers. In this paper, Citespace software package is applied to analyse the citation networks and other relevant data of the past eleven years (from 2006 to 2016) collected from Web of Science (WOS). Through this, a series of professional document analysis are conducted, including the production of core authors, the influence made by the most cited authors, keywords extraction and timezone analysis, hot topics of research, highly cited papers and trends with regard to co-citation analysis, etc. As a result, the development track of the IGB&SC domains is revealed and visualized and the following results reached: (i) in the research area of IGB&SC, the most productive researcher is Winters JV and Caragliu A is most influential on the other hand; (ii) different focuses of IGB&SC research have been emerged continually from 2006 to 2016 e.g. smart growth, sustainability, smart city, big data, etc.; (iii) Hollands's work is identified with the most citations and the emerging trends, as revealed from the bursts analysis in document co-citations, can be concluded as smart growth, the assessment of intelligent green building and smart city.

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A study on the preorthodontic prediction values versus the actual postorthodontic values in Class III surgery patients (골격성 III급 부정교합 환자에서 술전 교정전 예측치와 교정 후 실측치의 차이에 관한 연구)

  • Hwang, Chung-Ju;Kwon, Hee-Jeong
    • The korean journal of orthodontics
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    • v.33 no.1 s.96
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    • pp.1-9
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    • 2003
  • The purpose of this study was to find out and evaluate discrepancies between preorthodontic prediction values and actual postorthodontic values and factors contributing to it in 45 patients(17 male, 28 female) who were diagnosed as skeletal Class III ma)occlusion and received presurgical orthodontic treatment and orthognathic surgery at Yonsei university dental hospital. Lateral cephalograms were analysed at pretreatment(T1), orthodontic Prediction(T2), immediately before surgery(T3) and designated the landmark as coordinates or X and Y axes. The samples were divided according to ALD, upper and lower incisor inclination(Ul to SN, IMPA), COS, extraction, the position of extracted teeth and the statistical significance was tested to find out the factors contributing to the prediction. The results were as follows: 1. Differences between preorthodontic prediction values and actual postorthodontic values(T2-T3) were statistically significant(p<0.05) in the x coordinates of U6mbc, L1x and in y coordinates of U1i, U1x, U6me, U6mbc, L6mbc 2. The accuracy of prediction is relatively higher in horizontal changes compared to vortical changes. 3. The statistical significance(p<0.05) between prediction and actual values is observed more in the landmarks of the maxilla than the mandible. 4. Differences between prediction and actual values of incisor and first molar were statistically significant(p<0.05) according to extraction vs non-extraction, extraction type, ALD in the maxilla and according to ALD, IMPA in the mandible. Discrepancies between preorthodontic prediction values and actual postorthodontic values and factors contributing to the prediction must be considered in treatment planning of Cl III surgical patients to increase the accuracy of prediction. Furthermore future investigations are needed on the prediction of vortical changes.