• Title/Summary/Keyword: projection transformation

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A Study on 3D-Transformation of Krazovsky Coordinate System (Krassovsky 타원체 좌표의 3차원 변환에 대한 연구)

  • 김감래;전호원;현민호
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.19 no.2
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    • pp.117-123
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    • 2001
  • Requiring topographic information of map due to retaining russia map, which needed accuracy analysis of russia map and relation between its and south korea's map. In order to obtain exact location information from the map which has different reference datum. We have to operate coordinate transformation between maps applied different ellipsoid. In this paper, in order to evaluate accuracy between two maps applied different ellipsoid, it has studied theory of map projection and coordinate transformation. Then, select each point which can be recognized on the two maps for accuracy evaluation. After obtaining coordinate values for each point of same area, it is evaluated accuracy each geodetic coordinate and each TM coordinate. As a result of this study, the maps which have different reference datum could be used if the exact origin shift could be obtained and applied.

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A Note on Unavoidable Sets for a Spherical Curve of Reductivity Four

  • Kashiwabara, Kenji;Shimizu, Ayaka
    • Kyungpook Mathematical Journal
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    • v.59 no.4
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    • pp.821-834
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    • 2019
  • The reductivity of a spherical curve is the minimal number of times a particular local transformation called an inverse-half-twisted splice is required to obtain a reducible spherical curve from the initial spherical curve. It is unknown if there exists a spherical curve whose reductivity is four. In this paper, an unavoidable set of configurations for a spherical curve with reductivity four is given by focusing on 5-gons. It has also been unknown if there exists a reduced spherical curve which has no 2-gons and 3-gons of type A, B and C. This paper gives the answer to this question by constructing such a spherical curve.

New Family of the Exponential Distributions for Modeling Skewed Semicircular Data

  • Kim, Hyoung-Moon
    • The Korean Journal of Applied Statistics
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    • v.22 no.1
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    • pp.205-220
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    • 2009
  • For modeling skewed semicircular data, we derive new family of the exponential distributions. We extend it to the l-axial exponential distribution by a transformation for modeling any arc of arbitrary length. It is straightforward to generate samples from the f-axial exponential distribution. Asymptotic result reveals two things. The first is that linear exponential distribution can be used to approximate the l-axial exponential distribution. The second is that the l-axial exponential distribution has the asymptotic memoryless property though it doesn't have strict memoryless property. Some trigonometric moments are also derived in closed forms. Maximum likelihood estimation is adopted to estimate model parameters. Some hypotheses tests and confidence intervals are also developed. The Kolmogorov-Smirnov test is adopted for goodness of fit test of the l-axial exponential distribution. We finally obtain a bivariate version of two kinds of the l-axial exponential distributions.

Higher Order Coordinates Conversion for UTM Projection (UTM 투영에 의한 고차 좌표변환)

  • Seo, Seung-Nam
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.20 no.3
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    • pp.277-290
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    • 2008
  • In order to apply UTM coordinates conversion in zones larger than $14^{\circ}$ wide, a new conversion formula, based on the 12th expansion of Taylor series, is derived which is shown to be an extension of Thomas' formula(1952). Some examples of coordinate conversion between WGS84 and UTM are presented and convergences of computational results are also tested according to the order of formula. The present conversion formula can be used to make rectangular coordinate grid systems for numerical models to compute long wave propagation such as tide or tsunami around Korea.

Measuring Technique for Height of Burst using Stereo-vision Recognition (스테레오 영상인식을 이용한 신관폭발고도 계측기술)

  • Kang, Gyu-Chang;Choi, Ju-Ho;Park, Won-U;Hwang, Ui-Seong;Hong, Seong-Su;Yoo, Jun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.2 no.1
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    • pp.194-203
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    • 1999
  • This paper presents a measuring technique for bursting height of proximity fuses. This technique uses camera calibration to obtain the perspective transformation matrix describing the projection of the world coordinates to image coordinates, and calculates the world coordinates of bursting points from their image coordinates. The surface approximation algorithm by polynomial functions are also implemented.

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Invariant Iris Key Generation Method Robust To Stolen Token Scenario (ID 도난 시나리오에 강인한 불변 홍채 키 생성 방법)

  • Lee, Youn-Joo;Kim, Jai-Hie
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.959-960
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    • 2008
  • Recently, biometric authentication mechanism has been used to provide high level of security in cryptographic systems. In this paper, we propose an efficient method of generating invariant iris key to be applied in cryptographic systems. In order to generate iris key and improve the performance at the stolen token scenario, multiple random projection technique was combined with multiple linear transformation methods. From the experimental results, we proved that invariant iris keys were generated and the proposed method was robust to stolen token scenario.

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Development of on-line inverse kinematic algorithm and its experimental implementation (온라인 좌표 역변환 알고리듬의 개발과 이의 실험적 수행)

  • 오준호;박서욱;이두현
    • 제어로봇시스템학회:학술대회논문집
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    • 1988.10a
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    • pp.16-20
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    • 1988
  • This paper presents a new algorithm for solving the inverse kinematics in real-time applications. The end-tip movement of each link can be resolved into the basic resolution unit, .DELTA.l, which depends on link length, reduction ratio and resolution of the incremental encoder attached to the joint. When x- and y-axis projection of the end-tip movement are expressed in .DELTA.l unit, projectional increments .DELTA.x and .DELTA.y become -1, 0 or I by truncation. By using the incremental computation with these ternary value and some simple logic rules, a coordinate transformation can be realized. Through this approach, it should be noted that the floating-point arithmetic and the manipulation of trigonometric functions are completely eliminated. This paper demonstrates the proposed method in a parallelogram linkage type, two-link arm.

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Computing Planar Curve Offset Based on Surface/Surface Intersection (교차곡선 연산을 이용한 평면 곡선의 오프셋 계산)

  • 최정주
    • Korean Journal of Computational Design and Engineering
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    • v.3 no.2
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    • pp.127-134
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    • 1998
  • This paper presents d new algorithm to compute the offlet curve of a given planar parametric curve. We reduce the problem of computing an offset curve to that of intersecting a surface to a paraboloid. Given an input curve C(t)=(x(t), y(t))∈R², the corresponding surface D/sub c(t)/ is constructed symbolically as the envelope surface of a one-parameter family of tangent planes of the paraboloid Q:z=x²+y²along a lifted curve C(t)=(x(t), y(t), x(t)²+y(t)²∈Q. Given an offset distance d∈R, the offset curve C/sub d/(t) is obtained by the projection of the intersection curve of D/sub c(t)/ and a paraboloid Q:z=x²+y²-d² into the xy-plane.

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Wavelet-Based Face Recognition by Divided Area (웨이브렛을 이용한 공간적 영역분할에 의한 얼굴 인식)

  • 이성록;이상효;조창호;조도현;이상철
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2307-2310
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    • 2003
  • In this paper, a method for face recognition based on the wavelet packet decomposition is proposed. In the proposed method, the input image is decomposed by the 2-level wavelet packet transformation and then the face areas are defined by the Integral Projection technique applied to each of the 1-level subband images, HL and LH. After the defined face areas are divided into three areas, called top, bottom, and border, the mean and the variance of the three areas of the approximation image are computed, and the variance of the single predetermined face area for the rest of 15 detail images, from which the feature vectors of statistical measure are extracted. In this paper we use the wavelet packet decomposition, a generalization of the classical wavelet decomposition, to obtain its richer signal analysis features such as discontinuity in higher derivatives, self-similarity, etc. And we have shown that even with very simple statistical features such as mean values and variance we can make an excellent basis for face classification, if an appropriate probability distance is used.

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Development of Visual Inspection System for a CoG (CoG 시각 검사 시스템 개발)

  • Jeong Jong-Myeon;Kim Chi-Yeon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.4
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    • pp.667-673
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    • 2006
  • In this paper, we present a visual inspection system for a CoG using statistical features. After rotational error of an input image is compensated using Hough transformation, an inspection area is obtained by using projection method. Then the final result is derived from statistical features of segmented pad areas.