• 제목/요약/키워드: down-scaling

검색결과 204건 처리시간 0.027초

이미지의 임의의 스케일링을 위한 CSSF 샘플링 커널 기반의 cosine modulated 필터뱅크 (Arbitrary image scaling using a cosine-modulated filter bank with CSSF based sampling kernels)

  • 김진영;박기섭;남상원
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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    • pp.107-108
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    • 2007
  • In this paper, a cosine-modulated filter bank with a modified synthesis part is proposed for arbitrary scaling of images, whereby down/up-sampling kernels based on a compactly supported sampling function (CSSF) are utilized. Also, an optimized adaptive interpolation technique is incorporated into the filter bank structure to compensate for quality degradation arising in scaled images. Finally, simulation results verify that high quality images with arbitrary sizes can be obtained by applying the proposed approach.

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고속 Edge Map 생성 방법과 Edge 특성을 이용한 Edge Map 압축 (Fast Edge Map Method And Edge Map Compression Using Edge Features)

  • 김도현;김윤
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2015년도 제52차 하계학술대회논문집 23권2호
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    • pp.45-48
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    • 2015
  • 오늘날 하드웨어의 발전으로 인해 영상 해상도는 FHD를 넘어 4K UHD 이상의 영상 해상도가 사용화되고 있다. 하지만 Edge Map을 만들기 위해 일반적으로 사용하는 함수들은 Convolution 함수 일종으로서 영상의 해상도가 높을수록 더 많은 Complexity를 요구한다. 또한 현재 주요 영상 압축 기술인 JPEG, H.264/AVC High efficiency video coding(HEVC)같은 기법들은 자연 영상을 중점으로 개발되어 있어 Edge map 압축에 있어 자연 영상만큼의 효율을 보여주지 못하고 있다. 본 논문은 원 영상을 Down Scaling한 뒤 이미지를 다시 원래 사이즈로 Up Scaling하여 두 영상의 차를 이용한 Edge Map을 생성하는 새로운 방법을 소개한다. 생성된 Edge Map의 특성인 Histogram 값의 분포가 0을 중심으로 Gaussian 분포를 가지는 것을 이용한 Zero Based 코덱을 제안한다. 제안된 알고리즘을 이용하여 고 해상도 영상에서도 빠르게 Edge Map을 생성하고 제안한 코덱을 통해 해당 Edge map을 압축한 결과 다른 압축 기술보다 더 뛰어난 성능을 보여주었다.

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DSP 내의 IQ math를 이용한 회전자 위치 추정 정밀도 향상에 관한 연구 (A study about rotor position estimation enhance using IQ math in DSP)

  • 장중학;이광호;홍선기
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.98-100
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    • 2005
  • DSPs used at motor control are usually fixed point processor. They need scaling because they cannot excute floating point calculation. Scaling for floating point calculation makes the DSP's speed down, complex coding and etc. Therefore the IQ math is adopted. IQ math makes the fixed point processor possible to calculate the floating point math. In addition, IQ math can reduce memory usage and be more faster than that without IQ math. It seems that IQ math is appropriate in motor position control. In comparison of the position calculation between the IQ math, math function and the sine table, the method using IQ math is superior than other methods.

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Modeling Electrical Characteristics for Multi-Finger MOSFETs Based on Drain Voltage Variation

  • Kang, Min-Gu;Yun, Il-Gu
    • Transactions on Electrical and Electronic Materials
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    • 제12권6호
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    • pp.245-248
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    • 2011
  • The scaling down of metal oxide semiconductor field-effect transistors (MOSFETs) for the last several years has contributed to the reduction of the scaling variables and device parameters as well as the operating voltage of the MOSFET. At the same time, the variation in the electrical characteristics of MOSFETs is one of the major issues that need to be solved. Especially because the issue with variation is magnified as the drive voltage is decreased. Therefore, this paper will focus on the variations between electrical characteristics and drain voltage. In order to do this, the test patterned multi-finger MOSFETs using 90-nm process is used to investigate the characteristic variations, such as the threshold voltage, DIBL, subthreshold swing, transconductance and mobility via parasitic resistance extraction method. These characteristics can be analyzed by varying the gate width and length, and the number of fingers. Through this modeling scheme, the characteristic variations of multi-finger MOSFETs can be analyzed.

치면세마실습실 방문자의 구강보건행동과 구강보건의식에 관한 조사연구 (Investigational study on Oral Health Behavior and Awareness of visitor oral prophylaxis practice units)

  • 장계원;서은주;강용주
    • 한국치위생학회지
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    • 제7권4호
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    • pp.521-534
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    • 2007
  • The purpose of this study to provide base data of various dental hygiene management systems are necessary to improve the oral health of visitor oral prophylaxis practice units, investigating and analyzing the oral health behavior and awareness of 130 scaling patients who visited the oral prophylaxis practice units of J Health College from April to May of the year 2007. The following conclusions were obtained 1. 50% of them had more than 2 times of toothbrushing a day, and 45.5% had more than 3 times of toothbrushing a day. 2. Toothbrushing was done after having a breakfast in 75.4% and 71.5% brushed their teeth after having a dinner. As the time to brush teeth, 45.4% of the subjects spentless than 3 minutes and 39.2% of them spent less than 2 minutes, and 48.5% of them bushed their teeth in up and down directions and 43.8% used mixed approaches. 3. The usage period of a toothbrush lasted about 3 month in 33.1% and 26.2% used a toothbrush about 2 month, and 20% of the subjects had the experience of using dental floss or interdental brush. 4. 61.5% of the subjects had the experience of having scaling treatment. The frequency of scaling was found to be 38.5%. 5. As the cause of having caries of the teeth, 73.8% responded it as unfaithfully brushing and 50% the subjects considered smoking is very harmful to dental health. 6. The most important behavior for dental health was found to be not eating sugars that were pointed out by 75.4% of subjects. Based upon the above listed study results, various dental hygiene management systems are necessary to improve the oral health of patients who visit oral prophylaxis practice units, especially, the correct toothbrushing and periodic oral examination with preventive scaling were thought to be necessary.

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Atomic layer deposition으로 증착된 Ta2O5 박막의 전도기구에 대한 UV ozone annealing 효과 (Effects of UV ozone annealing on conduction mechanism in Ta2O5 thin films deposited by atomic layer deposition)

  • 엄다일;전인상;노상용;황철성;김형준
    • 한국재료학회:학술대회논문집
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    • 한국재료학회 2003년도 추계학술발표강연 및 논문개요집
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    • pp.57-57
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    • 2003
  • High dielectric constant materials (high K) have attracted a great deal of interest because of the dramatic scaling down of DRAM capacitor reaching its physical limit in terms of reduction of thickness. Among high-K materials that can replace silicon dioxide, tantalum pentoxide (Ta2O5) thin film, with their high dielectric constant (∼25) and good step coverage, is the candidate of choice.

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Preliminary Study of Micro Cold Gas Thruster

  • Moon, Seonghwan;Oh, Hwayollng;Huh, Hwanil
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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    • pp.617-621
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    • 2004
  • Miniaturization of subsystems including propulsion systems is recent trends in spacecraft technology. Small space vehicle propulsion is not only a technological challenge of a scaling system down, but also a combination of fundamental flow/combustion constraints. In this paper, physical constraints of micronozzle for cold gas micro-thruster are reviewed and discussed. Method to measure small thrust are also described.

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영상 다운 스케일링 기법 분석 (Survey on Image Down Scaling Techniques)

  • 박재현;조성인
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2020년도 추계학술대회
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    • pp.230-233
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    • 2020
  • 영상 다운스케일링 기법은 입력 영상의 해상도를 목적으로 하는, 입력영상의 해상도보다 낮은 해상도로 조정하는 기법을 일컫는다. 본 논문에서는 기존의 다운스케일링 기법들을 커널 기반의 방법과 프레임 단위의 최적화 기반 기법으로 분류하고 각 방법들의 대표 기법들에 대해서 분석한다. 이후, 최종적으로 그 결과를 도출하여 각 방법들의 특성을 도출한다.

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Estimating Non-Ideal Effects within a Top-Down Methodology for the Design of Continuous-Time Delta-Sigma Modulators

  • Na, Seung-in;Kim, Susie;Yang, Youngtae;Kim, Suhwan
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권3호
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    • pp.319-329
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    • 2016
  • High-level design aids are mandatory for design of a continuous-time delta-sigma modulator (CTDSM). This paper proposes a top-down methodology design to generate a noise transfer function (NTF) which is compensated for excess loop delay (ELD). This method is applicable to low pass loop-filter topologies. Non-ideal effects including ELD, integrator scaling issue, finite op-amp performance, clock jitter and DAC inaccuracies are explicitly represented in a behavioral simulation of a CTDSM. Mathematical modeling using MATLAB is supplemented with circuit-level simulation using Verilog-A blocks. Behavioral simulation and circuit-level simulation using Verilog-A blocks are used to validate our approach.

Design of the Experimental Simulator of Magnetic Sails

  • Funaki, Ikkoh;Fujita, Kazuhisa;Yamakawa, Hiroshi;Ogawa, Hiroyuki;Nonaka, Satoshi;Nakayama, Yoshinori
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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    • pp.278-281
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    • 2004
  • To realize magnetic sails, momentum of the solar wind should be efficiently transferred to a spacecraft via magnetic field, which is produced around a spacecraft. In this paper, two important physical processes are addressed: 1) diffusive processes caused by plasma turbulence at the magnetospheric boundary around the spacecraft; and 2) field aligned current loops that will electrically connect the magnetospheric boundary and the spacecraft. The idea of the magnetic sails will be demonstrated by an experimental simulator, in which a fast plasma beam will penetrate into a dipole magnetic field. For that purpose, the two important physical processes should be scaled down to a small laboratory experiment in a space chamber. From the scaling considerations, the interaction can be scaled down if high-speed and high-density $(10^{19}m^{-3})$ plasma jet is used with 1-T-class magnetic field.

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