• Title/Summary/Keyword: Reference objects

Search Result 311, Processing Time 0.027 seconds

Speckle Reduction in the Wavelet Domain for Image with Optical Coherence Tomography

  • Chang, Ju-Wan;Lee, Chang-Su;Na, Ji-Hoon;Paes, Stephane;Lee, Byeong-Ha
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.2459-2463
    • /
    • 2005
  • Optical coherence tomography (OCT) is high resolution medical imaging system which is obtaining image inside biological objects with non-destructive method. OCT system is based on Michelson interferometer with a reciprocating mirror in the reference arm and a biological object in the sample arm. The obtained OCT image suffers from a granular or mottled image, called speckle. Speckle is caused by random interferences between reflected coherence waves. In this paper, we propose effective speckle reduction method that uses wavelet transform. With wavelet domain image, sub-windowing and thresholding are performed. Finally, speckle reduction experiments for Misgurnus mizolepis skin and rat eye images are shown.

  • PDF

A Study on the High Speed Curve Generator Using 1-Dimensional Systolic Array Processor (1차원 시스톨릭 어레이 프로세서를 이용한 고속 곡선 발생기에 관한 연구)

  • 김용성;조원경
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.31B no.5
    • /
    • pp.1-11
    • /
    • 1994
  • In computer graphics since objects atre constructed by lines and curves, the high-speed curve generator is indispensible for computer aided design and simulatation. Since the functions of graphic generation can be represented as a series of matrix operations, in this paper, two kind of the high-speed Bezier curve generator that uses matrix equation and a recursive relation for Bezier polynomials are designed. And B-spline curve generator is designed using interdependence of B-spline blending functions. As the result of the comparison of designed curve generator and reference [5], [6] in the operation time and number of operators, the curve generator with 1-dimensional systolic array processor for matrix vector operation that uses matrix equation for Bezier curve is more effective.

  • PDF

The 3-D Object Recognition Using the Shape from Stereo Algorithm (스테레오 기법의 형태정보를 이용한 3차원 물체 인식)

  • 박성만;곽윤식;이대영
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.24 no.8B
    • /
    • pp.1500-1505
    • /
    • 1999
  • In this paper, we presented the stereo algorithm for 3-D object recognition. In order to solve the problem for matching time in existed methods, we proposed the method which used the moving direction vector. On the other hand, after we extracted the moving vectors by moving direction of objects, rotated object was matched on axis of it. Using the Hough transform, we obtained the 2-D synthesed image as reference images corresponding to the rate of moving, and then compared with the unknown input images.

  • PDF

Trend Analysis about 'The Attitude towards Money' (`화폐 태도' 관련 연구동향 분석)

  • Yoo, Soo-Hyun;Moon, Sook-Jae
    • Journal of Families and Better Life
    • /
    • v.28 no.5
    • /
    • pp.197-208
    • /
    • 2010
  • This study examines the 'Attitude towards Money' research trends and suggests future research issues and implications through a contents analysis. To accomplish the study object, 4 analysis categories were selected based on reference study to review the research subject, methods of data collection, research objects, and an analysis of the methods, found in 31 articles in journals and dissertations from 1996 to 2009. The were made in early 1990, (an increase in related research since 2000); however, the object of study is too limited, with an overemphasis on research methods and quantitative research methods. The research method of most articles was mainly limited to the quantitative study. Based on the results, research directions and research limitations were suggested for future leisure research.

Geospatial Information Extraction by using Digital Photogrammetry (수치사진측량을 이용한 지형공간정보 추출)

  • Yeu, Bock-Mo;Kim, Won-Dae
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.7 no.2 s.14
    • /
    • pp.81-91
    • /
    • 1999
  • The study on the updating of the database of Geo-Spatial Information System that is necessary condition to GSIS operation have executed actively. In this study, digital orthophotos were produced by using the product of digital photogrammetry process and then multiscale digital orthophoto maps were generated tv the concept of image pyramids. The produced digital orthophoto has 2.092 meters accuracy compared to 1:5,000 topographic map. This digital orthophoto can be implemented in various Geo-Spatial Information System, providing valuable spatial reference for other objects in the database.

  • PDF

Relocation of a Mobile Robot Using Sparse Sonar Data

  • Lim, Jong-Hwan
    • Journal of Mechanical Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.217-224
    • /
    • 2001
  • In this paper, the relocation of a mobile robot is considered such that it enables the robot to determine its position with respect to a global reference frame without any $\alpha$ priori position information. The robot acquires sonar range data from a two-dimensional model composed of planes, corners, edges, and cylinders. Considering individual range as data features, the robot searches the best position where the data features of a position matches the environmental model using a constraint-based search method. To increase the search efficiency, a hypothesize and-verify technique is employed in which the position of the robot is calculated from all possible combinations of two range returns that satisfy the sonar sensing model. Accurate relocation is demonstrated with the results from sets of experiments using sparse sonar data in the presence of unmodeled objects.

  • PDF

The Levitation Mass Method: A Precision Mass and Force Measurement Technique

  • Fujii, Yusaku
    • International Journal of Precision Engineering and Manufacturing
    • /
    • v.9 no.3
    • /
    • pp.46-50
    • /
    • 2008
  • The present status and future prospects of the levitation mass method (LMM), a technique for precision mass and force measurement, are reviewed. In the LMM, the inertial force of a mass levitated using a pneumatic linear bearing is used as the reference force applied to the objects being tested, such as force transducers, materials, or structures. The inertial force of the levitated mass is measured using an optical interferometer. We have modified this technique for dynamic force calibration of impact, oscillation, and step loads. We have also applied the LMM to material testing, providing methods for evaluating material viscoelasticity under an oscillating or impact load, evaluating material friction, evaluating the biomechanics of a human hand, and generating and measuring micro-Newton-level forces.

Localization of AUV Using Visual Shape Information of Underwater Structures (수중 구조물 형상의 영상 정보를 이용한 수중로봇 위치인식 기법)

  • Jung, Jongdae;Choi, Suyoung;Choi, Hyun-Taek;Myung, Hyun
    • Journal of Ocean Engineering and Technology
    • /
    • v.29 no.5
    • /
    • pp.392-397
    • /
    • 2015
  • An autonomous underwater vehicle (AUV) can perform flexible operations even in complex underwater environments because of its autonomy. Localization is one of the key components of this autonomous navigation. Because the inertial navigation system of an AUV suffers from drift, observing fixed objects in an inertial reference system can enhance the localization performance. In this paper, we propose a method of AUV localization using visual measurements of underwater structures. A camera measurement model that emulates the camera’s observations of underwater structures is designed in a particle filtering framework. Then, the particle weight is updated based on the extracted visual information of the underwater structures. The proposed method is validated based on the results of experiments performed in a structured basin environment.

Environment Map Based Disparity (환경맵 기반 디스페러티)

  • Ryoo Seung-Taek
    • Journal of Korea Multimedia Society
    • /
    • v.9 no.1
    • /
    • pp.109-118
    • /
    • 2006
  • In this paper, we suggest the environment based disparity method that calculate the depth value of the objects from environment maps. This method using the disparity of the environment map can calculate the depth value from two environment map that acquire at different viewpoint. This method can decide the visibility of the object whether it is occluded others or not. Also, we can analogize the depth value of the object that does not relate the reference plane(in case of being in the air) and make three dimensional environment model using the proposed method

  • PDF

Realization for Image Searching Engine with Moving Object Identification and Classification

  • Jung, Eun-Suk;Ryu, Kwang-Ryol;Sclabassi, Robert J.
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2007.10a
    • /
    • pp.301-304
    • /
    • 2007
  • A realization for image searching engine with moving objects identification and classification is presented in this paper. The identification algorithm is applied to extract difference image between input image and the reference image, and the classification is used the region segmentation. That is made the database for the searching engine. The experimental result of the realized system enables to search for human and animal at time intervals to use a surveillant system at inside environment.

  • PDF