• Title/Summary/Keyword: resolution compensation

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Hardware Implementation of Past Multi-resolution Motion Estimator for MPEG-4 AVC (MPEG-4 AVC를 위한 고속 다해상도 움직임 추정기의 하드웨어 구현)

  • Lim Young-hun;Jeong Yong-jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.11C
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    • pp.1541-1550
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    • 2004
  • In this paper, we propose an advanced hardware architecture for fast multi-resolution motion estimation of the video coding standard MPEG-1,2 and MPEG-4 AVC. We describe the algorithm and derive hardware architecture emphasizing the importance of area for low cost and fast operation by using the shared memory, the special ram architecture, the motion vector for 4 pixel x 4 pixel, the spiral search and so on. The proposed architecture has been verified by ARM-interfaced emulation board using Excalibur Altera FPGA and also by ASIC synthesis using Samsung 0.18 m CMOS cell library. The ASIC synthesis result shows that the proposed hardware can operate at 140 MHz, processing more than 1,100 QCIF video frames or 70 4CIF video frames per second. The hardware is going to be used as a core module when implementing a complete MPEG-4 AVC video encoder ASIC for real-time multimedia application.

Compensation Methods for Non-uniform and Incomplete Data Sampling in High Resolution PET with Multiple Scintillation Crystal Layers (다중 섬광결정을 이용한 고해상도 PET의 불균일/불완전 데이터 보정기법 연구)

  • Lee, Jae-Sung;Kim, Soo-Mee;Lee, Kwon-Song;Sim, Kwang-Souk;Rhe, June-Tak;Park, Kwang-Suk;Lee, Dong-Soo;Hong, Seong-Jong
    • Nuclear Medicine and Molecular Imaging
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    • v.42 no.1
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    • pp.52-60
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    • 2008
  • Purpose: To establish the methods for sinogram formation and correction in order to appropriately apply the filtered backprojection (FBP) reconstruction algorithm to the data acquired using PET scanner with multiple scintillation crystal layers. Materials and Methods: Formation for raw PET data storage and conversion methods from listmode data to histogram and sinogram were optimized. To solve the various problems occurred while the raw histogram was converted into sinogram, optimal sampling strategy and sampling efficiency correction method were investigated. Gap compensation methods that is unique in this system were also investigated. All the sinogram data were reconstructed using 20 filtered backprojection algorithm and compared to estimate the improvements by the correction algorithms. Results: Optimal radial sampling interval and number of angular samples in terms of the sampling theorem and sampling efficiency correction algorithm were pitch/2 and 120, respectively. By applying the sampling efficiency correction and gap compensation, artifacts and background noise on the reconstructed image could be reduced. Conclusion: Conversion method from the histogram to sinogram was investigated for the FBP reconstruction of data acquired using multiple scintillation crystal layers. This method will be useful for the fast 20 reconstruction of multiple crystal layer PET data.

A Study on the Introduction of Food Safety Damage Relief System (식품안전 피해구제제도의 도입방안에 관한 연구)

  • Lee, Byung-Jun
    • Journal of Arbitration Studies
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    • v.27 no.4
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    • pp.199-222
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    • 2017
  • Currently, many punitive damages (or statutory damages) and class action laws are discussed in relation to the consumer damage relief system. It is in the background of the argument that the introduction of such a victim relief system will solve many small and large consumer damages. There are many cases in which the punitive damages compensation or the class action system are introduced in relation to the food safety damage naturally. Although the introduction of such a system can clearly help the consumer to relieve large-scale damage, it can not solve all the problems at once because the company can reject the system despite the introduction of such a system. In particular, class action lawsuits should have the same type of damage, but most of the damage caused by food safety is accompanied by physical harm, resulting in various complications such as the physical characteristics of the victim, the health environment. The class action system may not provide a solution in that the content and type of the damage may be different. In this regard, this study aims to investigate the introduction of the food safety damage relief system through the introduction of an administrative dispute settlement system by an administrative agency that occupies an absolute position in the existing consumer protection from this point of view. In reality, the Food and Drug Administration, which is the largest among government agencies related to food, operates a passive attitude consumer protection system such as function like guidance, supervision and surveillance. And it is necessary to make a complementary proposal. In the current law, there is only a small part of the consumer protection work that is positively legal, and even after the damage is scientifically identified, it is not possible to present the solution to the damage suffered by the consumer through legislation. This is a fact that has been raised. In this paper, we propose a reasonable and rapid disaster relief procedure through a separate mechanism within the administrative agency, which is the administration agency, that the dispute settlement procedure due to food safety damage is insufficient by solving the case through the court through counseling, dispute adjustment and civil proceedings. In order to solve the problem of food insecurity and the food industry, various ways of rational solution of the problem were considered. The possibility of (1) Establishment of a food safety dispute resolution committee; (2) Establishment of a food safety disaster relief committee; and (3) Establishment of a food safety disaster relief committee was discussed. In addition, a plan for the creation of a food damage compensation fund was also proposed.

Application of Temperature-compensated Resistivity Probe in the Field (온도보상형 전기저항 프로브의 현장 적용성 평가)

  • Jung, Soon-Hyuck;Yoon, Hyung-Koo;Lee, Jong-Sub
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.4C
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    • pp.117-125
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    • 2011
  • The practical use of the electrical resistivity, which can makes the acquirement of the high resolution data in specific area, is increased in order to obtain a reasonable data for a ground investigation. The objective of this study is development of TRPF(Temperature-compensated Resistivity Probe for Field test), and an application in the field test for obtaining a reliable electrical resistivity value about considering the temperature effects. Temperature sensor is attached at 15mm, 30mm, 90mm below from the cone tip in consideration with the results of temperature transient process of cone probe and safety, and the angle of cone tip is $60^{\circ}$ for geometrical reason and minimizing the disturbance during the penetration test. Diameter of the cone probe is equally 35.7mm and penetration rate is 2 cm/sec for a comparison with standard cones such as CPT and SPT, and others. The temperature change is instantly observed around $4^{\circ}C$ when touching the ground, and the comparing results among the other cones indicates that the temperature compensation should be conducted in the ground survey using the electrical resistivity. This study shows that the necessity of temperature effects compensation during penetration test through the development and field verification of TRPF (Temperature-compensated Resistivity Probe for Field test).

Motion Linearity-based Frame Rate Up Conversion Method (선형 움직임 기반 프레임률 향상 기법)

  • Kim, Donghyung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.7
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    • pp.734-740
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    • 2017
  • A frame rate up-conversion scheme is needed when moving pictures with a low frame rate is played on appliances with a high frame rate. Frame rate up-conversion methods interpolate the frame with two consecutive frames of the original source. This can be divided into the frame repetition method and motion estimation-based the frame interpolation one. Frame repetition has very low complexity, but it can yield jerky artifacts. The interpolation method based on a motion estimation and compensation can be divided into pixel or block interpolation methods. In the case of pixel interpolation, the interpolated frame was classified into four areas, which were interpolated using different methods. The block interpolation method has relatively low complexity, but it can yield blocking artifacts. The proposed method is the frame rate up-conversion method based on a block motion estimation and compensation using the linearity of motion. This method uses two previous frames and one next frame for motion estimation and compensation. The simulation results show that the proposed algorithm effectively enhances the objective quality, particularly in a high resolution image. In addition, the proposed method has similar or higher subjective quality than other conventional approaches.

A Study on Possibility of Improvement of MIR Brightness Temperature Bias Error of KOMPSAT-3A Using GEOKOMPSAT-2A (천리안2A호를 이용한 다목적실용위성3A호 중적외선 밝기 온도 편향오차 개선 가능성 연구)

  • Kim, HeeSeob
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.12
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    • pp.977-985
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    • 2020
  • KOMPSAT-3A launched in 2015 provides Middle InfraRed(MIR) images with 3.3~5.2㎛. Though the satellite provide high resolution images for estimating bright temperature of ground objects, it is different from existing satellites developed for natural science purposes. An atmospheric compensation process is essential in order to estimate the surface brightness temperature from a single channel MIR image of KOMPSAT-3A. However, even after the atmospheric compensation process, there is a brightness temperature error due to various factors. In this paper, we analyzed the cause of the brightness temperature estimation error by tracking signal flow from camera physical characteristics to image processing. Also, we study on possibility of improvement of MIR brightness temperature bias error of KOMPSAT-3A using GEOKOMPSAT-2A. After bias compensation of a real nighttime image with a large bias error, it was confirmed that the surface brightness temperature of KOMPSAT-3A and GEOKOMPSAT-2A have correlation. We expect that the GEOKOMPSAT-2A images will be helpful to improve MIR brightness temperature bias error of KOMPSAT-3A.

Fabrication of the Imaging Lens for Mobile Camera using Embossing Method (엠보싱 공법에 의한 카메라 모듈용 광학렌즈 성형기법에 대한 연구)

  • Lee, C.H.;Jin, Y.S.;Noh, J.E.;Kim, S.H.;Jang, I.C.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.05a
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    • pp.79-83
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    • 2007
  • We have developed a compact and cost-effective camera module on the basis of wafer-scale replication technology. A multiple-layered structure of several aspheric lenses in a mobile camera module is first assembled by bonding multiple glass-wafers on which 2-dimensional replica arrays of identical aspheric lenses are UV-embossed, followed by dicing the stacked wafers and packaging them with image sensor chips. We have demonstrated a VGA camera module fabricated by the wafer-scale replication processing with various UV-curable polymers having refractive indices between 1.4 and 1.6, and with three different glass-wafers of which both surfaces are embossed as aspheric lenses having 200 um sag-height and aspheric-coefficients of lens polynomials up to tenth-order. We have found that precise compensation in material shrinkage of the polymer materials is one of the most technical challenges, in order to achieve a higher resolution in wafer-scaled lenses for mobile camera modules.

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Develoment of high-sensitivity wireless strain sensor for structural health monitoring

  • Jo, Hongki;Park, Jong-Woong;Spencer, B.F. Jr.;Jung, Hyung-Jo
    • Smart Structures and Systems
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    • v.11 no.5
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    • pp.477-496
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    • 2013
  • Due to their cost-effectiveness and ease of installation, wireless smart sensors (WSS) have received considerable recent attention for structural health monitoring of civil infrastructure. Though various wireless smart sensor networks (WSSN) have been successfully implemented for full-scale structural health monitoring (SHM) applications, monitoring of low-level ambient strain still remains a challenging problem for WSS due to A/D converter (ADC) resolution, inherent circuit noise, and the need for automatic operation. In this paper, the design and validation of high-precision strain sensor board for the Imote2 WSS platform and its application to SHM of a cable-stayed bridge are presented. By accurate and automated balancing of the Wheatstone bridge, signal amplification of up to 2507-times can be obtained, while keeping signal mean close to the center of the ADC span, which allows utilization of the full span of the ADC. For better applicability to SHM for real-world structures, temperature compensation and shunt calibration are also implemented. Moreover, the sensor board has been designed to accommodate a friction-type magnet strain sensor, in addition to traditional foil-type strain gages, facilitating fast and easy deployment. The wireless strain sensor board performance is verified through both laboratory-scale tests and deployment on a full-scale cable-stayed bridge.

Study on Velocity In-homogeneous Effect in fat and its Correction in Ultrasound Imaging System (초음파 의료영상에서 지방조직의 음속도 불균일 효과의 영향과 그 보상에 관한 연구)

  • Kim, Jae-Hyeon;Bae, Mu-Ho;Jeong, Mok-Geun
    • Journal of Biomedical Engineering Research
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    • v.19 no.1
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    • pp.9-18
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    • 1998
  • In this paper, we present the degradation of focusing induced by velocity inhomogeneity in human tissue. For simulation, the fatty layer which is the major factor of degradation for its lower velocity, is modeled as a uniform velocity perturbation layer. And we simulate the degradation of resolution resulting from change of beam path due to refraction and the time delay due to velocity difference. We show that focusing error can be compensated for considering the velocity inhomogeneity only. The proposed compensation method can be operated in real time in the presently used digital focusing systems.

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FABRICATION AND TEST OF AN OPTICAL GRISM (가시광선용 그리즘의 제작과 성능시험)

  • Lee, D.H.;Song, J.W.;Yoon, T.S.
    • Publications of The Korean Astronomical Society
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    • v.28 no.3
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    • pp.75-82
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    • 2013
  • An optical grism for education is fabricated and tested. It is composed of a transmission grating as dispersion element and a prism as diffraction angle compensation device. The transmission grating is Edmundoptics #49-584(spatial frequency 600 lines/mm, dimension $50mm{\times}50mm$). The prism is the fused silica type with angles ($41.3^{\circ}$, $-48.7^{\circ}$, $-90^{\circ}$). The grism device is fabricated by bonding the transmission grating and the prism with an optical adhesive. The zig for assembling the grism, telescope and camera is composed of an aluminum tube, an aluminum disk ring and a T-ring camera adaptor. The fabricated optical grism spectrograph is tested in laboratory using Halogen lamp and Neon lamp with DSLR camera. And the grism assembled with reflector telescope is tested in a field using stellar light. The results show good agreements with design parameters. The wavelength coverage range of the grism is 250 nm at the un-deviated wavelength of 506 nm. The wavelength resolution is 0.11 nm/pixel.