• Title/Summary/Keyword: Correspondences

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Adjustment of Exterior Orientation Parameters Geometric Registration of Aerial Images and LIDAR Data (항공영상과 라이다데이터의 기하학적 정합을 위한 외부표정요소의 조정)

  • Hong, Ju-Seok;Lee, Im-Pyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.27 no.5
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    • pp.585-597
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    • 2009
  • This research aims to develop a registration method to remove the geometric inconsistency between aerial images and LIDAR data acquired from an airborne multi-sensor system. The proposed method mainly includes registration primitives extraction, correspondence establishment, and EOP(Exterior Orientation Parameters) adjustment. As the registration primitives, we extracts planar patches and intersection edges from the LIDAR data and object points and linking edges from the aerial images. The extracted primitives are then categorized into horizontal and vertical ones; and their correspondences are established. These correspondent pairs are incorporated as stochastic constraints into the bundle block adjustment, which finally precisely adjusts the exterior orientation parameters of the images. According to the experimental results from the application of the proposed method to real data, we found that the attitude parameters of EOPs were meaningfully adjusted and the geometric inconsistency of the primitives used for the adjustment is reduced from 2 m to 2 cm before and after the registration. Hence, the results of this research can contribute to data fusion for the high quality 3D spatial information.

Efficient image-stitching using preprocessing for a super resolution image (전처리를 활용한 고해상도 영상을 위한 효율적인 영상 스티칭)

  • Bae, JoungEun;Yoo, Hoon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.9
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    • pp.1738-1743
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    • 2017
  • This paper presents an efficient image stitching method using preprocessing in order to generate a super resolution image. Two-dimensional (2D) scanners are consistently used in various areas but they have limitations such as paper sizes and materials. To overcome these problem with low-cost, an efficient imaging stitching method is proposed for producing a super resolution panorama image. To scan a very large sized paper using mobile phones, a simple portable cradle which fixes height is employed producing an input image set. To improve matching performance, a preprocessing method is introduced before searching correspondences. Then alpha blending is applied to an input image set to produce a super resolution panorama image. The proposed method is faster and easier than the existing method which is employed by Open CV. Experiment results show that the proposed method is three times faster and performs better than the existing method.

Effect of hanging-type sand fence on characteristics of wind-sand flow fields

  • Cheng, Jian-jun;Lei, Jia-qiang;Li, Sheng-yu;Wang, Hai-feng
    • Wind and Structures
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    • v.22 no.5
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    • pp.555-571
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    • 2016
  • A hanging-type sand-retaining wall is a very common sand-blocking fence structure used to prevent sand movement. This type of wall is widely used along the Qinghai-Tibet and Gobi desert railways in Xinjiang, Western China. To analyze the characteristics of wind-sand flow fields under the effect of such a sand fence structure, a wind tunnel test and a field test were carried out. The wind tunnel test showed the zoning characteristics of the flow fields under the effect of the hanging-type sand-retaining wall, and the field test provided the sediment transport data for effective wind-proof interval and the sand resistance data in the front and behind the sand-retaining wall. The consistency of the wind-sand flow fields with the spatial distribution characteristic of wind-carried sand motion was verified by the correspondences of the acceleration zone in the flow field and the negative elevation points of the percentage variations of the sand collection rate. The spatial distribution characteristic of the field sand collection data further showed the spatial structural characteristic of the sandy air currents under the action of the hanging-type sand-retaining wall and the sand resistance characteristic of the sand-retaining wall. This systematic study on the wind-sand flow fields under the control of the hanging-type sand-retaining wall provides a theoretical basis for the rational layout of sand control engineering systems and the efficient utilization of a hanging-type sand-retaining wall.

Translation Method of '-hada' verb in a Korean-to-Japanese Machine Translation (한-일 기계번역에서 '하다'용언의 번역 방법)

  • Moon, Kyong-Hi
    • Journal of the Korea Society of Computer and Information
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    • v.10 no.4 s.36
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    • pp.181-189
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    • 2005
  • Due to grammatical similarities, even a one-to-one mapping between Korean and Japanese morphemes can usually result in a high quality Korean-to-Japanese machine translation. So most of Korean-to-Japanese machine translation are based on a one-to-one mapping relation. Most of Korean '-hada' verbs, which consist of a noun and '-hada', also correspond to Japanese '-suru' verbs, which consist of a noun and '-suru', so we generally use one-to-one mapping relation between them. However, the applications only by one-to-one mapping may sometimes result in incorrect Japanese correspondences in some cases that Korean 'hada' verbs don't correspond to Japanese 'suru' verbs. In these cases, we need to handle a noun and '-hada' as one translation unit. Therefore, this paper examined the characteristics of Korean '-hada' verb and proposed transfer rules of Korean 'hada' verb, applying for various states of input sentences such as discontinuity due to inserted words between a noun and '-hada', passivization, and modification of '-hada' verb. In an experimental evaluation, the proposed method was very effective for handling '-hada' verb in a Korean-to-Japanese machine translation, showing high quality of translation results.

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Foreground object detection in projection display (프로젝션 화면에서 전경물체 검출)

  • Kang Hyun;Lee Chang Woo;Park Min Ho;Jung Keechul
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.41 no.1
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    • pp.27-37
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    • 2004
  • The detection of foreground objects in a projection display using color information can be hard due to changing lighting conditions and complex backgrounds. Accordingly, the current paper proposes a foreground object detection method using color information that is obtained from the input image to the Projector and an image captured by a camera above the projection display. After pixel correspondences between the two images are found by calibrating the geometry distortion and color distortion, the natural color variations are estimated for the projection display. Then, any pixel that has another variation not resulting from natural geometry or color distortion is considered a part of foreground objects, because a foreground object in a projection display changes the values of pixels. As shown by experimental results, the proposed foreground detection method is applicable to an interactive projection display system such as the DigitalDesk

3-D Pose Estimation of an Elliptic Object Using Two Coplanar Points (두 개의 공면점을 활용한 타원물체의 3차원 위치 및 자세 추정)

  • Kim, Heon-Hui;Park, Kwang-Hyun;Ha, Yun-Su
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.49 no.4
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    • pp.23-35
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    • 2012
  • This paper presents a 3-D pose (position and orientation) estimation method for an elliptic object in 3-D space. It is difficult to resolve the problem of determining 3-D pose parameters with respect to an elliptic feature in 3-D space by interpretation of its projected feature onto an image plane. As an alternative, we propose a two points-based pose estimation algorithm to seek the 3-D information of an elliptic feature. The proposed algorithm determines a homogeneous transformation uniquely for a given correspondence set of an ellipse and two coplanar points that are defined on model and image plane, respectively. For each plane, two triangular features are extracted from an ellipse and two points based on the polarity in 2-D projection space. A planar homography is first estimated by the triangular feature correspondences, then decomposed into 3-D pose parameters. The proposed method is evaluated through a series of experiments for analyzing the errors of 3-D pose estimation and the sensitivity with respect to point locations.

An Object Tracking Method for Studio Cameras by OpenCV-based Python Program (OpenCV 기반 파이썬 프로그램에 의한 방송용 카메라의 객체 추적 기법)

  • Yang, Yong Jun;Lee, Sang Gu
    • The Journal of the Convergence on Culture Technology
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    • v.4 no.1
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    • pp.291-297
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    • 2018
  • In this paper, we present an automatic image object tracking system for Studio cameras on the stage. For object tracking, we use the OpenCV-based Python program using PC, Raspberry Pi 3 and mobile devices. There are many methods of image object tracking such as mean-shift, CAMshift (Continuously Adaptive Mean shift), background modelling using GMM(Gaussian mixture model), template based detection using SURF(Speeded up robust features), CMT(Consensus-based Matching and Tracking) and TLD methods. CAMshift algorithm is very efficient for real-time tracking because of its fast and robust performance. However, in this paper, we implement an image object tracking system for studio cameras based CMT algorithm. This is an optimal image tracking method because of combination of static and adaptive correspondences. The proposed system can be applied to an effective and robust image tracking system for continuous object tracking on the stage in real time.

A research on Mathematical Invention via Real Analysis Course in University (대학교의 해석학 강좌에서 학생들의 수학적 발명에 관한 연구)

  • Lee, Byung-Soo
    • Communications of Mathematical Education
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    • v.22 no.4
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    • pp.471-487
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    • 2008
  • Inventive mathematical thinking, original mathematical problem solving ability, mathematical invention and so on are core concepts, which must be emphasized in all branches of mathematical education. In particular, Polya(1981) insisted that inventive thinking must be emphasized in a suitable level of university mathematical courses. In this paper, the author considered two cases of inventive problem solving ability shown by his many students via real analysis courses. The first case is about the proof of the problem "what is the derived set of the integers Z?" Nearly all books on mathematical analysis sent the question without the proof but some books said that the answer is "empty". Only one book written by Noh, Y. S.(2006) showed the proof by using the definition of accumulation points. But the proof process has some mistakes. But our student Kang, D. S. showed the perfect proof by using The Completeness Axiom, which is very useful in mathematical analysis. The second case is to show the infinite countability of NxN, which is shown by informal proof in many mathematical analysis books with formal proofs. Some students who argued the informal proof as an unreasonable proof were asked to join with us in finding the one-to-one correspondences between NxN and N. Many students worked hard and find two singled-valued mappings and one set-valued mapping covering eight diagrams in the paper. The problems are not easy and the proofs are a little complicated. All the proofs shown in this paper are original and right, so the proofs are deserving of inventive mathematical thoughts, original mathematical problem solving abilities and mathematical inventions. From the inventive proofs of his students, the author confirmed that any students can develope their mathematical abilities by their professors' encouragements.

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A partially occluded object recognition technique using a probabilistic analysis in the feature space (특징 공간상에서 의 확률적 해석에 기반한 부분 인식 기법에 관한 연구)

  • 박보건;이경무;이상욱;이진학
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.11A
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    • pp.1946-1956
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    • 2001
  • In this paper, we propose a novel 2-D partial matching algorithm based on model-based stochastic analysis of feature correspondences in a relation vector space, which is quite robust to shape variations as well as invariant to geometric transformations. We represent an object using the ARG (Attributed Relational Graph) model with features of a set of relation vectors. In addition, we statistically model the partial occlusion or noise as the distortion of the relation vector distribution in the relation vector space. Our partial matching algorithm consists of two-phases. First, a finite number of candidate sets areselected by using logical constraint embedding local and structural consistency Second, the feature loss detection is done iteratively by error detection and voting scheme thorough the error analysis of relation vector space. Experimental results on real images demonstrate that the proposed algorithm is quite robust to noise and localize target objects correctly even inseverely noisy and occluded scenes.

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Design and Implementation of RFID Based u-SCM System for Fiber and Apparel Industry (섬유 및 의류산업의 RFID 기반 u-SCM 시스템의 설계 및 구현)

  • Moon, Il-Whan;Ahn, Jae-Geun;Kim, Sam-Keun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.36 no.8B
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    • pp.986-995
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    • 2011
  • Recently, the market of fiber and apparel industry is rapidly changing from producer to consumer oriented. This trend emphasizes the necessity of SCM systems being able to do flexible correspondences to the market changing through synthetically reflecting consumers' various needs and a variety of patterns. However, because traditional SCMs manage their supply chains being based on bar code systems from the production to the distribution, they are suffering from the needs of real time information sharing and have their essential restrictions in the response to the environmental changes of the market and consumers' needs. This paper suggests a new RFID based u-SCM system optimized into the fiber and apparel industry. The proposed system has the benefits that through basing on RPID can collect information of the production and the distribution real time and make better use of it and connect to the legacy systems organically via Web services and rapidly respond to the market changing and consumers' needs. Through implementation, it is demonstrated that the proposed system can effectively facilitate them.