• 제목/요약/키워드: Digital Calibration

검색결과 379건 처리시간 0.026초

Surpassing Tradeoffs by Separation: Examples in Transmission Line Resonators, Phase-Locked Loops, and Analog-to-Digital Converters

  • Sun, Nan;Andress, William F.;Woo, Kyoung-Ho;Ham, Don-Hee
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제8권3호
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    • pp.210-220
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    • 2008
  • We review three examples (an on-chip transmission line resonator [1], a phase-locked loop [2], and an analog-to-digital converter [3]) of design tradeoffs which can in fact be circumvented; the key in each case is that the parameters that seem to trade off with each other are actually separated in time or space. This paper is an attempt to present these designs in such a way that this common approach can hopefully be applied to other circuits. We note reader that this paper is not a new contribution, but a review in which we highlight the common theme from our published works [1-3]. We published a similar paper [4], which, however, used only two examples from [1] and [2]. With the newly added content from [3] in the list of our examples, the present paper offers an expanded scope.

디지털 방사선 영상의 편차지수를 이용한 의료영상 품질관리에 관한 연구 (A Study on Quality Control for Medical Image by Using Deviation Index of Digital Radiology)

  • 정회원;민정환
    • 대한방사선기술학회지:방사선기술과학
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    • 제43권2호
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    • pp.115-121
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    • 2020
  • In a digital radiation system using a Flat Panel Detector, we attempted to the quality control of digital radiography system using the Exposure Index and Deviation Index. Calibration was performed with the radiation quality suggested by the International Electrotechnical Commission, and through an experiment using a phantom, appropriate inspection radiation conditions applicable to medical institutions were selected. The study was conducted using the selected radiation conditions. Through those chest posterior anterior image, information such as examination conditions and exposure index was obtained. The deviation index was derived by analyzing the exposure index based on the target exposure index calculated by the phantom study. As for the analyzed exposure index, 97.1% was distributed within the range of ± 2.0 based on the deviation index. Quality control of medical images should be performed through management of inspection conditions through exposure index and deviation index and management of medical images.

Data Transmission through Power Line of Smart Transmitter

  • Kim, Jong-Hyun;Kang, Hyun-Kook;Seong, Poong-Hyun
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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    • pp.471-476
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    • 1996
  • In this study, the method to use the phase shift keying (PSK) communication technique in smart transmitter is presented. In nuclear applications. smart transmitters for various parameters are expected to improve the accuracy of measurement and to reduce the load of calibration work. The capability of communication in field level is the most important merit of the smart transmitter. The most popular method is using of digital and analog techniques simultaneously - transmitting measurements from the field at 4∼20mA while modulating the current to carry digital information in both directions over the same twisted pairs. Conventional smart transmitters use the frequency shift keying (FSK) method for digital communication. Generally, however, the FSK method has the speed limit at 1200 bps. Amount of information to transmit becomes increasing as the processing technique is improved. The PSK method is noticeable alternative for high speed digital communication, but it has non-zero DC component. In order to use the PSK method in the field transmission with smart transmitter, the method to remove the DC component is studied in this work.

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Digital mapping of soil carbon stock in Jeolla province using cubist model

  • Park, Seong-Jin;Lee, Chul-Woo;Kim, Seong-Heon;Oh, Taek-Keun
    • 농업과학연구
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    • 제47권4호
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    • pp.1097-1107
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    • 2020
  • Assessment of soil carbon stock is essential for climate change mitigation and soil fertility. The digital soil mapping (DSM) is well known as a general technique to estimate the soil carbon stocks and upgrade previous soil maps. The aim of this study is to calculate the soil carbon stock in the top soil layer (0 to 30 cm) in Jeolla Province of South Korea using the DSM technique. To predict spatial carbon stock, we used Cubist, which a data-mining algorithm model base on tree regression. Soil samples (130 in total) were collected from three depths (0 to 10 cm, 10 to 20 cm, 20 to 30 cm) considering spatial distribution in Jeolla Province. These data were randomly divided into two sets for model calibration (70%) and validation (30%). The results showed that clay content, topographic wetness index (TWI), and digital elevation model (DEM) were the most important environmental covariate predictors of soil carbon stock. The predicted average soil carbon density was 3.88 kg·m-2. The R2 value representing the model's performance was 0.6, which was relatively high compared to a previous study. The total soil carbon stocks at a depth of 0 to 30 cm in Jeolla Province were estimated to be about 81 megatons.

계측기기 자동교정 및 모니터링 기술개발 (Development of auto calibration program for instruments)

  • 조현섭;민진경
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2007년도 춘계학술발표논문집
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    • pp.154-157
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    • 2007
  • 본 논문에서는 컴퓨터로 정밀 계측기기들을 자동 제어하고 데이터를 측정하기 위하여 기존의 상용 프로그램을 사용하지 않고 Excel VBA(Visual Basic for Applications)를 이용하는 방법에 대하여 연구 하였다. 이는 반복측정 및 통계적 수치계산 등에서 많은 장점을 지니고 있어 수많은 국가교정기관 및 일반 산업체에서 유용하게 사용될 수 있으리라 사료된다.

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Construction of HTS Multi-channel SQUID System

  • Lee, S.M.;Park, W.K.;Lee, H.J.;Moon, S.H.;Lim, S.H.;Kim, D.Y.;Oh, B.
    • Progress in Superconductivity
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    • 제2권1호
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    • pp.47-50
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    • 2000
  • We have constructed a multi-channel SQUID magnetometer system. The system is designed to operate normally with 10 high temperature direct coupled SQUIDs. The main features of the system include a remote control by serial communication, low noise with wide bandwidth and high slew rate by several MHz modulation, signal conditioning and calibration by digital signal processing.

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화상처리법을 이용한 곡면변형률 측정에 관한 연구(II) (A Study on the Measurement of Surface-strain Using the Image Processing Technique(II))

  • 한상준;김영수;김형종;오수익
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1997년도 추계학술대회논문집
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    • pp.142-146
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    • 1997
  • An automated surface-strain measuring system is developed in the present study, which consists of the hardware to capture and to display digital images and the software to calculate the 3-D informations of grid points. The software is implemented using the image processing technique, and includes a program for the camera calibration and the post-processor to display the strain distribution. An LDH(limitting dome height) test specimen is measured its surface-strain as an application of the present system.

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LBS를 위한 코드 DGPS 위치 정확도 향상에 관한 연구 (The Improvement of Code DGPS Positioning Accuracy for LBS)

  • 강준묵;조성호;임영빈
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 추계학술발표회 논문집
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    • pp.29-32
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    • 2004
  • Purpose of this study is to maximize inflection of code DGPS for LBS. Compare calibration method with pseudo range revision method for this and decides revision method. Also, examine variation that occur by inconsistency of satellite association of user and standard department for problem solution by satellite association. Model revision information through AR model who use RLSLF and minimises satellite association problem. I wish to do optimized code DGPS of digital map so that is possible through an experiment.

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정밀 계측기기 자동교정 프로그램 개발 (Development of auto calibration program for exact instruments)

  • 조현섭
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2009년도 춘계학술발표논문집
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    • pp.446-449
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    • 2009
  • 본 논문에서는 컴퓨터로 정밀 계측기기을 자동 제어하고 데이터를 측정하기 위하여 기존의 상용 프로그램을 사용하지 않고 Excel VBA(Visual Basic for Applications)를 이용하는 방법에 대하여 연구하였다. 이는 반복측정 및 통계적 수치계산 등에서 많은 장점을 지니고 있어 수많은 국가교정기관 및 일반 산업체에서 유용하게 사용될 수 있으리라 사료된다.

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광원의 영향을 제거한 디지털 카메라의 색보정 (Colorimetric calibration of digital camera excluding illuminant effect)

  • 류종우;박승옥;김홍석
    • 한국광학회:학술대회논문집
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    • 한국광학회 2003년도 제14회 정기총회 및 03년 동계학술발표회
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    • pp.120-121
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    • 2003
  • 디지털 카메라로 촬영한 이미지를 모니터에 디스플레이 해보면 원래 이미지의 색과는 다르게 보인다. 그 이유는 촬영할 때 주변 광원의 영향이 이미지에 미치고 두 장치간의 색 특성이 다르기 때문이다. 두 장치간의 색 특성이 다른 이유 때문에 본 연구의 목표인 디지털 카메라의 색보정 이외에 모니터의 색보정도 고려되어야 한다. 디지털 카메라의 옵션 중에는 White Balance 기능이 있어서 자체적으로 주변 광원의 변화에 따른 색보정을 수행하지만 White Balance 기능만으로는 주변 광원의 영향을 제어하는데 한계가 있다. (중략)

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