• Title/Summary/Keyword: Look-Up Table

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A Study on the Optimization of color in Digital Printing (디지털 인쇄에 있어서 컬러의 최적화에 관한 연구)

  • Kim, Jae-Hae;Lee, Sung-Hyung;Cho, Ga-Ram;Koo, Chul-Whoi
    • Journal of the Korean Graphic Arts Communication Society
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    • v.26 no.1
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    • pp.51-64
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    • 2008
  • In this paper, an experiment was done where the input(scanner, digital still camera) and monitor(CRT, LCD) device used the linear multiple regression and the GOG (Gain-Offset-Gamma) characterization model to perform a color transformation. Also to color conversion method of the digital printer it used the LUT(Look Up Table), 3dimension linear interpolation and a tetrahedron interpolation method. The results are as follows. From color reappearance of digital printing case of monitor, the XYZ which it converts in linear multiple regression of input device it multiplied the inverse matrix, and then it applies the inverse GOG model and after color converting the patch of the result most which showed color difference below 5 at monitor RGB value. Also, The XYZ which is transmitted from the case input device which is a printer it makes at LAB value to convert an extreme, when the LAB value which is converted calculating the CMY with the LUT and tetrahedral interpolations the color conversion which considers the black quantity was more accurate.

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A Speed Sensorless Induction Motor Control System using Direct Torque Control for Torque Ripple Reduction (직접 토크제어의 토크맥동 저감을 위한 속도검출기 없는 유도전동기 제어 시스템)

  • Kim, Nam-Hun;Kim, Min-Ho;Kim, Min-Huei;Kim, Dong-Hee;Hwang, Don-Ha
    • Proceedings of the KIEE Conference
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    • 2001.07b
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    • pp.986-988
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    • 2001
  • This paper presents a digitally speed sensorless control system for induction motor with direct torque control (DTC). Some drawbacks of the classical DTC are the relatively large torque ripple in a low speed range and notable current pulsation during steady state. They are reflected speed response and increased acoustical noise. In this paper, the DTC quick response are preserved at transient state, while better qualify steady state performance is produced by space vector modulation (SVM). The system are closed loop stator flux and torque observer for wide speed range that inputs are currents and voltages sensing of motor terminal, model reference adaptive control (MRAC) with rotor flux linkages for the speed fuming signal at low speed range, two hysteresis controllers and optimal switching look-up table. Simulation results of the suggest system for the 2.2 [kW] general purposed induction motor are presented and discussed.

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ATMOSPHERIC AEROSOL DETECTION AND ITS REMOVEAL FOR SATELLITE DATA

  • Lee, Dong-Ha;Lee, Kwon-Ho;Kim, Young-Joon
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.598-601
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    • 2006
  • Satellite imagery may contain large regions covered with atmospheric aerosol. A high-resolution satellite imagery affected by non-homogenous aerosol cover should be processed for land cover study and perform the radiometric calibration that will allow its future application for Korea Multi-Purpose Satellite (KOMPSAT) data. In this study, aerosol signal was separated from high resolution satellite data based on the reflectance separation method. Since aerosol removal has a good sensitivity over bright surface such as man-made targets, aerosol optical thickness (AOT) retrieval algorithm could be used. AOT retrieval using Look-up table (LUT) approach for utilizing the transformed image to radiometrically compensate visible band imagery is processed and tested in the correction of satellite scenery. Moderate Resolution Imaging Spectroradiometer (MODIS), EO-1/HYPERION data have been used for aerosol correction and AOT retrieval with different spatial resolution. Results show that an application of the aerosol detection for HYPERION data yields successive aerosol separation from imagery and AOT maps are consistent with MODIS AOT map.

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Development of On-line Performance Diagnostic Program of a Helicopter Turboshaft Engine

  • Kong, Chang-Duk;Koo, Young-Ju;Kho, Seong-Hee;Ryu, Hye-Ok
    • International Journal of Aeronautical and Space Sciences
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    • v.10 no.2
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    • pp.34-42
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    • 2009
  • Gas turbine performance diagnostics is a method for detecting, isolating and quantifying faults in gas turbine gas path components. On-line precise fault diagnosis can promote greatly reliability and availability of gas turbine in real time operation. This work proposes a GUI-type on-line diagnostic program using SIMULINK and Fuzzy-Neuro algorithms for a helicopter turboshaft engine. During development of the diagnostic program, a look-up table type base performance module are used for reducing computer calculating time and a signal generation module for simulating real time performance data. This program is composed of the on-line condition monitoring program to monitor on-line measuring performance condition, the fuzzy inference system to isolate the faults from measuring data and the neural network to quantify the isolated faults. Evaluation of the proposed on-line diagnostic program is performed through application to the helicopter engine health monitoring.

An Efficient Correlation Scheme for the GPS Software Receiver

  • Lim, Deok-Won;Cho, Deuk-Jae;Park, Chan-Sik;Lee, Sang-Jeong
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1216-1221
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    • 2005
  • The GPS software receiver based on the SDR(Software Defined Radio) technology provides the ability to easily adopt other signal processing algorithms without changing or modifying the hardware of the GPS receiver. However, it is difficult to implement the GPS software receiver using a commercial processor because of heavy computation load for processing the GPS signals in real time. This paper proposes an efficient GPS signal processing scheme and correlator structure to reduce the computation load for processing the GPS signal in the GPS software receiver, which uses a patterned look-up table method to generate the correlation value between the GPS signals and the replica signals. In this paper, it is explained that the computation load of the proposed scheme is much smaller than that of the previous GPS signal processing scheme. Finally, the processing time of the proposed scheme is compared with that of the previous scheme, and the improvement is shown from the viewpoint of the computation load.

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Passband Digital Symbol Clock Recovery Scheme for 51.84Mbps VDSL QAM Receiver (51.84Mbps VDSL QAM 수신기를 위한 통과대역 디지털 심볼 클록 복원방식)

  • Lee, Jae-Ho;Kim, Jae-Won;Jeong, Hang-Geun;Jeong, Jin-Gyun
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.37 no.2
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    • pp.77-84
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    • 2000
  • In this paper, we discuss a symbol clock extraction scheme based on maximizing the band-edge component of the transmitted signal frequency spectrum for applications to 51.84Mbps VDSL system which uses a 16-QAM. The major characteristics of the digital PLL are examined. In addition, we suggest an efficient design method of a sinusoidal look-up table which is used for NCO.

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A Study on the Object Angle Inference in a Sonar Sensor Array System (초음파센서 배열 시스템에서 물체의 각도 추론에 관한 연구)

  • 나승유;박민상
    • Proceedings of the IEEK Conference
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    • 1998.06a
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    • pp.271-274
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    • 1998
  • Ultrasonic sensors are becoming indispensable components in every sector of automation equipments due to many advantages. But the main purposes of the noncontact sensing device are rather narrowly confined within object detection and distance measurement. To widen the realm of the applications to object recognition, ultrasonic sensors need to improve the recognition resolution to a certain amount. To resolve the problem of spatial resolution restriction, an increased number of the sensors in the forms of a linear array or 2-dimensional array of the sensor has been used. Also better resolution has been obtained by shifting the array in several steps using mechanical actuators. For an object recognition using ultrasonic sensors, measurements of distance, shift, oblique angle in certain ranges should be obtained. But a little attention has been paid to the measurement of angles. In this paper we propose a practical method for an object angular value detection in addition to distance measurement in ultrasonic sensor array system with little additional hardware burden. Using the established measurement look-up table for the variations of distance, shift, angle and transmitter voltages for each sensor characteristics, a set of different return echo signals for adjacent receivers are processed to provide enhanced angular value reading for an object.

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Low-latency SAO Architecture and its SIMD Optimization for HEVC Decoder

  • Kim, Yong-Hwan;Kim, Dong-Hyeok;Yi, Joo-Young;Kim, Je-Woo
    • IEIE Transactions on Smart Processing and Computing
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    • v.3 no.1
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    • pp.1-9
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    • 2014
  • This paper proposes a low-latency Sample Adaptive Offset filter (SAO) architecture and its Single Instruction Multiple Data (SIMD) optimization scheme to achieve fast High Efficiency Video Coding (HEVC) decoding in a multi-core environment. According to the HEVC standard and its Test Model (HM), SAO operation is performed only at the picture level. Most realtime decoders, however, execute their sub-modules on a Coding Tree Unit (CTU) basis to reduce the latency and memory bandwidth. The proposed low-latency SAO architecture has the following advantages over picture-based SAO: 1) significantly less memory requirements, and 2) low-latency property enabling efficient pipelined multi-core decoding. In addition, SIMD optimization of SAO filtering can reduce the SAO filtering time significantly. The simulation results showed that the proposed low-latency SAO architecture with significantly less memory usage, produces a similar decoding time as a picture-based SAO in single-core decoding. Furthermore, the SIMD optimization scheme reduces the SAO filtering time by approximately 509% and increases the total decoding speed by approximately 7% compared to the existing look-up table approach of HM.

Modeling of Fine Cracks using Fuzzy Mathematical Morphology (퍼지 수학적 형태학을 이용한 미세균열 모델링)

  • Park, In-Kyoo;Choi, Gyoo-Seok
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.5
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    • pp.105-111
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    • 2010
  • In this paper the elasticity of fault-detection algorithm based on fuzzy logic is proposed through lots of experiments, justifying its validity. The four mathematical morpholgical operators was defined to detect the cracks. The cracks was detected via center of area method with ${\lambda}$-fuzzy measure of fuzzy sets. However generally favorable, the result owes to how adequate the lighting device is designed in case of the so far fine crack of pieces. In an attempt to improve the response of the system, It is designed to minimize the use of memory via LookUp table in software.

Design of Simple-structured Fuzzy Logic System based Driving Controller for Mobile Robot (단순구조 퍼지논리시스템을 이용한 이동 로봇의 주행 제어기 설계)

  • Choi, Byung-Jae;Jin, Sheng
    • Journal of the Korean Institute of Intelligent Systems
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    • v.22 no.1
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    • pp.1-6
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    • 2012
  • In this paper, we present an obstacle avoidance control algorithm for mobile robots based on SFLC (single-input fuzzy logic controller) with an efficient fuzzy logic look-up table to replace the traditional complicated operation. This method achieves better performance than traditional methods in terms of efficiency. The output of a SFLC leads the robot to the target automatically although many obstacles on the path. Our experiments show that the robot has good performance in the view of path tracking and other efficiency.