• Title/Summary/Keyword: multiple transform

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Selective Rendering of Specific Volume using a Distance Transform and Data Intermixing Method for Multiple Volumes (거리변환을 통한 특정 볼륨의 선택적 렌더링과 다중 볼륨을 위한 데이타 혼합방법)

  • Hong, Helen;Kim, Myoung-Hee
    • Journal of KIISE:Computer Systems and Theory
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    • v.27 no.7
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    • pp.629-638
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    • 2000
  • The main difference between mono-volume rendering and multi-volume rendering is data intermixing. In this paper, we first propose a selective rendering method for fast visualizing specific volume according to the surface level and then present data intermixing method for multiple volumes. The selective rendering method is to generate distance transformed volume using a distance transform to determine the minimum distance to the nearest interesting part and then render it. The data intermixing method for multiple volumes is to combine several volumes using intensity weighted intermixing method, opacity weighted intermixing method, opacity weighted intermixing method with depth information and then render it. We show the results of selective rendering of left ventricle and right ventricle generated from EBCT cardiac images and of data intermixing for combining original volume and left ventricular volume or right ventricular volume. Our method offers a visualization technique of specific volume according to the surface level and an acceleration technique using a distance transformed volume and the effective visual output and relation of multiple images using three different intermixing methods in three-dimensional space.

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A Study of the comparison of Inversion of Rayleigh wave Group and Phase Velocities for Regional Near-Surface 2-Dimensional Velocity Structure (천부지각 2차원 속도구조를 위한 레일리파의 군속도와 위상속도 역산의 비교 연구)

  • Lee, Bo-Ra;Jung, Hee-Ok
    • 한국지구물리탐사학회:학술대회논문집
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    • 2006.06a
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    • pp.51-59
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    • 2006
  • The surface wave data obtained in a tidal flat located in the sw coast of the Korean Peninsula were used to analyse the shear wave velocity structure of the area. First, the phase velocity dispersion curves were obtained by the tau-p stacking method and the group velocity dispersion curves by a wavelet transform method and the Multiple Filtering Technique by Dziewonski. The phase velocity dispersion curves exhibited bigger errors than the group velocity curves. The results showed that the wavelet transform method was more effective in separating the fundamental and the 1st higher mode group velocity curves than the Multiple Filtering Technique. Combined use of the fundamental and the 1st higher mode group velocity dispersion curves in the inversion for the shear wave velocity structure gave better spatial resolution compared when the fundamental mode group velocity was used alone. This study indicates that the group velocity dispersion curves can be used in the inversion of Rayleigh waves for the shear wave velocity structure, especially effectively with the higher mode group velocity curves together.

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Multiple Description Coding using Unequal MDSQ in Wavelet Domain

  • Yoon, Eung-Sik;Park, Kwang-Pyo;Lee, Keun-Young
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.281-284
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    • 2002
  • Error resilience for image coding is an important component of multimedia communication system. Error resilience schemes address loss recovery from the compression perspective. Multiple description coding (MDC) is one of the error resilience techniques promising for robust video transmission. It is the way to achieve tradeoff description such as scalar quantization, correlating transform and the quantized frame expansion. In this paper, we consider Multiple Description Scalar Quantization (MDSQ) to wavelet domain. Conventional MDSQ schemes considered description with equal weights in each sub-bands. But, we can see that the each sub-bands is unequal contribution to whole image quality. Therefore, we experiment the multiple design MDSQ table to make probability of zero index high, which gives high efficiency in arithmetic symbol coder. We also compare our proposed method with the conventional methods and show improved performance in terms of redundancy-rate-distortion.

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Optimal design of a piezoelectric passive damper for vibrating plates

  • Yun, Chul-Yong;Kim, Seung-Jo
    • International Journal of Aeronautical and Space Sciences
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    • v.7 no.2
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    • pp.42-49
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    • 2006
  • In this paper, an efficient piezoelectric passive damper is newly devised to suppress the multi-mode vibration of plates. To construct the passive damper, the piezoelectric materials are utilized as energy transformer, which can transform the mechanical energy to electrical energy. To dissipate the electrical energy transformed from mechanical energy, multiple resonant shunted piezoelectric circuits are applied. The dynamic governing equations of a coupled electro-mechanical piezoelectric with multiple piezoelectric patches and multiple resonant shunted circuits is derived and solved for the one edge clamped plate. The equations of motion of the piezoelectrics and shunted circuits as well as the plate are discretized by finite element method to estimate more exactly the effectiveness of the piezoelectric passive damper. The method to find the optimal location of a piezoelectric is presented to maximize effectiveness for desired modes. The electro-mechanical coupling term becomes important parameter to select the optimal location.

Quantitative Analysis by Diffuse Reflectance Infrared Fourier Transform and Linear Stepwise Multiple Regression Analysis I -Simultaneous quantitation of ethenzamide, isopropylantipyrine, caffeine, and allylisopropylacetylurea in tablet by DRIFT and linear stepwise multiple regression analysis-

  • Park, Man-Ki;Yoon, Hye-Ran;Kim, Kyoung-Ho;Cho, Jung-Hwan
    • Archives of Pharmacal Research
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    • v.11 no.2
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    • pp.99-113
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    • 1988
  • Quantitation of ethenzamide, isopropylantipyrine and caffeine takes about 41 hrs by conventional GC method. Quantitation of allylisoprorylacetylurea takes about 40 hrs by conventional UV method. But quantitation of them takes about 6 hrs by DRIFT developing method. Each standard and sample sieved, powdered and acquired DRIFT spectrum. Out of them peak of each component was selected and ratio of each peak to standard peak was acquired, and then linear stepwise multiple regression was performed with these data and concentration. Reflectance value, Kubelka-Munk equation and Inverse-Kubelka-Munk equation were modified by us. Inverse-Kubelka-Munk equation completed the deficit of Kubelka-Munk equation. Correlation coefficients acquired by conventioanl GC and UV against DRIFT were more than 0.95.

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Embedded Zerotree Wavelet Coding Based On Multiple Description (다중 기술에 근거한 엠베디드 제로트리 웨이블릿 부호화)

  • Eom, Il-Gyu
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.39 no.3
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    • pp.42-48
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    • 2002
  • Multiple description coding Is source coding for multiple channels such that a decoder which receives an arbitrary subset of the channels may produce a useful reconstruction. This paper presents an efficient multiple description coder using a newly designed EZW coding method. We first propose EZW coder which has expanded threshold and two subordinate passes. And then we present multiple description coder which has two coding channels using the proposed EZW coders. To evaluate the performance of the proposed coder, we provide an image coding applications with two descriptions and compare multiple description image coding results reported to date. Simulation results show that the proposed method has a better performance than the polyphase transform method.

Handwritten Numeral Recognition Using Karhunen-Loeve Transform Based Subspace Classifier and Combined Multiple Novelty Classifiers (Karhunen-Loeve 변환 기반의 부분공간 인식기와 결합된 다중 노벨티 인식기를 이용한 필기체 숫자 인식)

  • 임길택;진성일
    • Journal of the Korean Institute of Telematics and Electronics C
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    • v.35C no.6
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    • pp.88-98
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    • 1998
  • Subspace classifier is a popular pattern recognition method based on Karhunen-Loeve transform. This classifier describes a high dimensional pattern by using a reduced dimensional subspace. Because of the loss of information induced by dimensionality reduction, however, a subspace classifier sometimes shows unsatisfactory recognition performance to the patterns having quite similar principal components each other. In this paper, we propose the use of multiple novelty neural network classifiers constructed on novelty vectors to adopt minor components usually ignored and present a method of improving recognition performance through combining those with the subspace classifier. We develop the proposed classifier on handwritten numeral database and analyze its properties. Our proposed classifier shows better recognition performance compared with other classifiers, though it requires more weight links.

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An Improvement on FFT-Based Digital Implementation Algorithm for MC-CDMA Systems (MC-CDMA 시스템을 위한 FFT 기반의 디지털 구현 알고리즘 개선)

  • 김만제;나성주;신요안
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.7A
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    • pp.1005-1015
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    • 1999
  • This paper is concerned with an improvement on IFFT (inverse fast Fourier transform) and FFT based baseband digital implementation algorithm for BPSK (binary phase shift keying)-modulated MC-CDMA (multicarrier-code division multiple access) systems, that is functionally equivalent to the conventional implementation algorithm, while reducing computational complexity and bandwidth requirement. We also derive an equalizer structure for the proposed implementation algorithm. The proposed algorithm is based on a variant of FFT algorithm that utilizes a N/2-point FFT/IFFT for simultaneous transformation and reconstruction of two N/2-point real signals. The computer simulations under additive white Gaussian noise channels and frequency selective fading channels using equal gain combiner and maximal ratio combiner diversities, demonstrate the performance of the proposed algorithm.

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Volume holographic correlator for fingerprint recognition (지문 인식을 위한 체적 홀로그래픽 광상관기)

  • 이승현;김은수
    • Korean Journal of Optics and Photonics
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    • v.9 no.6
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    • pp.385-389
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    • 1998
  • In this paper, we propose an optical correlator system using volume holograms for database of matched filters. Optical correlator has high speed and parallel processing characteristics of optics. Matched filters are recorded into a volume hologram that can store data with high density, transfer them with high speed, and select a randomly chosen data element. The multiple reference images of database are prerecorded in a photorefractive crystal in the form of Fourier transform images, simply by passing the image displayed in a spatial light modulator through a Fourier transform lens. The angular multiplexing method for multiple holograms of database can be achieved by rotating the crystal by use of a step motor. Experimental results show that the proposed system can be used for the fingerprint recognition.

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Study of Methodology for Recognizing Multiple Objects (다중물체 인식 방법론에 관한 연구)

  • Lee, Hyun-Chang;Koh, Jin-Kwang
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.7
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    • pp.51-57
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    • 2008
  • In recent computer vision or robotics fields, the research area of object recognition from image using low cost web camera or other video device is performed actively. As study for this, there are various methodologies suggested to retrieve objects in robotics and vision research areas. Also, robotics is designed and manufactured to aim at doing like human being. For instance, a person perceives apples as one see apples because of previously knowing the fact that it is apple in one's mind. Like this, robotics need to store the information of any object of what the robotics see. Therefore, in this paper, we propose an methodology that we can rapidly recognize objects which is stored in object database by using SIFT (scale invariant feature transform) algorithm to get information about the object. And then we implement the methodology to enable to recognize simultaneously multiple objects in an image.

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