• Title/Summary/Keyword: A. affine

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A Comparison on the Image Normalizations for Image Information Estimation

  • Kang, Hwan-Il;Lim, Seung-Chul;Kim, Kab-Il;Son, Young-I
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2385-2388
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    • 2005
  • In this paper, we propose the estimation method for the image affine information for computer vision. The first estimation method is given based on the XYS image normalization and the second estimation method is based on the image normalization by Pei and Lin. The XYS normalization method turns out to have better performance than the method by Pei and Lin. In addition, we show that rotation and aspect ratio information can be obtained using the central moments of both the original image and the sensed image. Finally, we propose the modified version of the normalization method so that we may control the size of the image.

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Improvement of Photogrammetry Image Merging in Satellite Image Processing (인공위성 영상처리를 위한 사진접합정확도 향상기법)

  • Kang, In-Joon;Choi, Chul-Ung
    • Journal of Korean Society for Geospatial Information Science
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    • v.2 no.1 s.3
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    • pp.93-98
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    • 1994
  • This image of Kangseogu in Pusan, is a digital merge of aerial photos by scale of 1/1,200 map. The merge was carried out 2nd affine and bilinear interpolation. It can improve digital classification to help choose training sites and interprete classification results, and improve visual interpretation, as in this case, by adding detailed information to the multispectral TM data.

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On the Derivation of TSK Fuzzy Model for Nonlinear Differentical Equations (비선형 미분방정식의 TSK 퍼지 모델 유도에 관하여)

  • 이상민;조중선
    • Journal of the Korean Institute of Intelligent Systems
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    • v.11 no.8
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    • pp.720-725
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    • 2001
  • Derivation of TSK fuzzy model from nonlinear differential equation is fundamental issue in the field of theoretical fuzzy control. The method which does not yield affine local differential equations at off-equilibrium points is proposed in this paper. A prototype TSK fuzzy model which has triangular membership functions for linguistic terms of the antecedent part is derived systematically. And then GA is used to modify the membership functions optimally. Simulation results show the validity of the proposed method.

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A study of low-temperature and mountain epilithic diatom community in mountain stream at the Han River system, Korea

  • Kim, Yong Jin;Lee, Ok Min
    • Journal of Ecology and Environment
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    • v.41 no.8
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    • pp.213-222
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    • 2017
  • Background: This study was conducted to assess the physicochemical water quality and the altitudinal distribution of low-temperature and mountain epilithic diatom (LTMD) community in Buk and Hangae streams that are located in Seorak Mountain with the height of 1708 m in Korea. And the community characteristics of LTMD found in the Buk and Hangae streams were compared to that of LTMD from the Han River system. Results: The physicochemical water qualities of Buk and Hangae streams were determined to be very clean. As a result of analyzing the community composition, 135 taxa of epilithic diatoms were determined, and 22 taxa appeared including Hannaea arcus var. subarcus which are known to have low-temperature and mountain ecological characteristics in the literatures. The relative frequencies of LTMD were 37.0~0.9% range from the upper to lower regions. Although Diatoma tenuis, Eunotia minor, and Gomphonema affine are known to be ubiquitous in streams and lakes, in this research, the three taxa were added into low-temperature and mountain epilithic diatom, since D. tenuis and E. minor appeared only in altitudes above 600 m, and G. affine had the highest relative frequency during spring and fall in altitudes above 700 m, when water temperature was around $10^{\circ}C$. Conclusions: Among the 24 taxa of low-temperature and mountain epilithic diatom (LTMD) (including the 3 taxa added in this study), 14 taxa (Diatoma hyemalis, D. mesodon, D. tenuis, Hannaea arcus, H. arcus var. subarcus, Ulnaria inaequalis, Eunotia bilunaris, E. implicata, E. minor, E. muscicola, E. silvahercynia, E. septena, Delicata delicatula, and Gomphonema affine) represented the characteristics of LTMD very well; they grow best in water temperatures below $15^{\circ}C$ in Buk and Hangae streams and Han River system.

Robust Estimation of Camera Motion Using A Local Phase Based Affine Model (국소적 위상기반 어파인 모델을 이용한 강인한 카메라 움직임 추정)

  • Jang, Suk-Yoon;Yoon, Chang-Yong;Park, Mig-Non
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.46 no.1
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    • pp.128-135
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    • 2009
  • Techniques for tracking the same region of physical space with the temporal sequences of images by matching the contours of constant phase show robust and stable performance in relative to the tracking techniques using or assuming the constant intensity. Using this property, we describe an algorithm for obtaining the robust motion parameters caused by the global camera motion. First, we obtain the optical flow based on the phase of spacially filtered sequential images on the region in a direction orthogonal to orientation of each component of gabor filter bank. And then, we apply the least squares method to the optical flow to determine the affine motion parameters. We demonstrate hat proposed method can be applied to the vision based pointing device which estimate its motion using the image including the display device which cause lighting condition varieties and noise.

Algebraic Structure for the Recognition of Korean Characters (한글 문자의 인식을 위한 대수적 구조)

  • Lee, Joo-K.;Choo, Hoon
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.12 no.2
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    • pp.11-17
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    • 1975
  • The paper examined the character structure as a basic study for the recognition of Korean characters. In view of concave structure, line structure and node relationship of character graph, the algebraic structure of the basic Korean characters is are analized. Also, the degree of complexities in their character structure is discussed and classififed. Futhermore, by describing the fact that some equivalence relations are existed between the 10 vowels of rotational transformation group by Affine transformation of one element into another, it could be pointed out that the geometrical properting in addition to the topological properties are very important for the recognition of Korean characters.

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A Taxonomic Study of Genus Staurastrum (Chlorophyta) Including Korean Unrecorded Species (한국산 미기록종을 포함한 팔장고말속식물 (녹조식물) 에 대한 분류학적 연구)

  • Moon, Byeong-Ryeol;Lee, Ok-Min
    • Korean Journal of Ecology and Environment
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    • v.37 no.3 s.108
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    • pp.282-296
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    • 2004
  • While more than 1,000 taxa in Staurastrum were found worldwide, in Korea only 119 taxa, of 68 species 42 varieties 9 forms, were reported so far. In this study, 23 taxa (19 species 4 varieties) of Staurastrum were collected from 15 freshwaters in Korea from Feb. through Nov., 2003. Among these taxa, 12 were newly recorded to Korea. Therefore, the total number of Staurastrum in Korea should be 131 taxa, of 77 species 45 varieties 9 forms, adding 12 newly found taxa. Most of the collected species were coincided with the characteristics previously described, but the sizes of 8 taxa including S. affine were smaller than those previously described. The 7 taxa including S. cerastesa have shown a little dissimilarity in the morphology of semicell and the decoration of cell wall.

Individual Variable Step-Size Subband Affine Projection Algorithm (독립 가변 스텝사이즈 부밴드 인접투사 알고리즘)

  • Choi, Hun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.26 no.3
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    • pp.443-448
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    • 2022
  • This paper presents a subband affine projection algorithm with variable step size to improve convergence performance in adaptive filtering applications with long adaptive filters and highly correlated input signals. The proposed algorithm can obtain fast convergence speed and small steady-state error by using different step sizes for each adaptive sub-filter in the subband structure to which polyphase decomposition and noble identity are applied. The step size derived to minimize the mean square error of the adaptive filter at each update time shows better convergence performance than the existing algorithm using a variable step size. In order to confirm the convergence performance of the proposed algorithm, which is superior to the existing algorithm, computer simulations are performed for mean square deviation(MSD) for AR(1) and AR(2) colored input signals considering the system identification model.

Update of Digital Map by using The Terrestrial LiDAR Data and Modified RANSAC (수정된 RANSAC 알고리즘과 지상라이다 데이터를 이용한 수치지도 건물레이어 갱신)

  • Kim, Sang Min;Jung, Jae Hoon;Lee, Jae Bin;Heo, Joon;Hong, Sung Chul;Cho, Hyoung Sig
    • Journal of Korean Society for Geospatial Information Science
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    • v.22 no.4
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    • pp.3-11
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    • 2014
  • Recently, rapid urbanization has necessitated continuous updates in digital map to provide the latest and accurate information for users. However, conventional aerial photogrammetry has some restrictions on periodic updates of small areas due to high cost, and as-built drawing also brings some problems with maintaining quality. Alternatively, this paper proposes a scheme for efficient and accurate update of digital map using point cloud data acquired by Terrestrial Laser Scanner (TLS). Initially, from the whole point cloud data, the building sides are extracted and projected onto a 2D image to trace out the 2D building footprints. In order to register the footprint extractions on the digital map, 2D Affine model is used. For Affine parameter estimation, the centroids of each footprint groups are randomly chosen and matched by means of a modified RANSAC algorithm. Based on proposed algorithm, the experimental results showed that it is possible to renew digital map using building footprint extracted from TLS data.

Antioxidant and Tyrosinase Inhibitory Activities of Dicaffeoylquinic Acid Derivatives Isolated from Gnaphalium Affine D. DON (떡쑥 추출물로부터 분리된 Dicaffeoylquinic Acid 유도체들의 항산화 및 타이로시네이즈 저해 활성)

  • Im, Na Ri;Kim, Hae Soo;Ha, Ji Hoon;Noh, Geun Young;Park, Soo Nam
    • Applied Chemistry for Engineering
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    • v.26 no.4
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    • pp.470-476
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    • 2015
  • In this study, three dicaffeoylquinic acids (DCQAs) isolated from Gnaphalium affine D. DON. extracts were structurally identified and evaluated for their antioxidant activities, cellular protective effects, and tyrosinase inhibitory activities. The ethyl acetate fraction of G. affine was chromatographed, which yielded 3 DCQA derivatives of 1-3 : 3,5-dicaffoylquinic acid (3,5-DCQA, 1), 4,5-dicaffeoylquinic acid (4,5-DCQA, 2), 1,5-dicaffoylquinic acid (1,5-DCQA, 3). The structure of each compounds was determined using $^1H$ NMR and MS analyses. Compounds of 1-3 showed strong free radical (1,1-diphenyl-2-picrylhydrazyl, DPPH) scavenging activities ($FSC_{50}=3.70$, 5.80, and $5.50{\mu}M$, respectively) compared to those of a commonly used lipophilic antioxidant, (+)-${\alpha}$-tocopherol ($21.90{\mu}M$). Cellular protective effects of 1-3 compounds on the $^1O_2$ sensitized photohemolysis of human erythrocytes were similar to (+)-${\alpha}$-tocopherol. 1-3 compounds also exhibited higher tyrosinase inhibitory effects ($IC_{50}=0.15$, 0.16, and 0.13 mM) compared to arbutin (0.33 mM), known as a skin-whitening agent. These results indicate that three DCQA derivatives may be applied as an antioxidant and a skin whitening agent in food or cosmetic industries.