• 제목/요약/키워드: separate reference

검색결과 172건 처리시간 0.024초

혼합정합 전달정렬시 해상항체의 가관측성 향상조건에 관한 연구 (A study of observability enhancement by matching methods at sea)

  • 김경주;고영웅;박찬웅
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.867-870
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    • 1996
  • Often an INS has to be aligned in navigation. In these cases it is necessary to obtain some reference information on the state of the aligned INS(Slave) such as its position, its velocity of its angular rate. Usually the reference information is velocity which is supplied by another reference INS. In the alignment state the velocity computed by the reference INS(Master) is compared with that computed by the slave INS and the difference which is indicative of the slave misalignment with respect to the master, is processed by a Kalman filter which estimates misalignment as well as the slave gyro and accelerometer error states. The operation of aligning a slave INS with a master INS comparing quantities computed by both INS is known as transfer alignment. The delivery vehicle performs error these maneuvers enable the TA Kalman filter to separate between the tilt errors and the accelerometer biases which otherwise are unobservable. The basic objective this paper is to study the observability enhancement by ship's maneuvering and matching methods during transfer alignment at sea.

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기준신호 보상회로를 이용한 더블 샘플링 방식의 비냉각형 볼로미터 검출회로 설계에 관한 연구 (A Study on Double Sampling Design of CMOS ROIC for Uncooled Bolometer Infrared Sensor using Reference Signal Compensation Circuit)

  • 배영석;정은식;오주현;성만영
    • 한국전기전자재료학회논문지
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    • 제23권2호
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    • pp.89-92
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    • 2010
  • A bolometer sensor used in an infrared thermal imaging system has many advantages on the process because it does not need a separate cooling system and its manufacturing is easy. However the sensitivity of the bolometer is low and the fixed pattern noise(FPN) is large, because the bolometer sensor is made by micro electro mechanical systems (MEMS). These problems can be fixed-by using the high performance readout integrated circuit(ROIC) with noise reduction techniques. In this paper, we propose differential delta sampling circuit to remove the mismatch noise of ROIC itself, the FPN of the bolometer. And for reduction of FPN noise, the reference signal compensation circuit which compensate the reference signal by using on-resistance of MOS transistor was proposed.

반복측정의 불확도를 이용한 인증값 확인 (Confirmation of reference value using uncertainty of multiple measurements)

  • 최종오;소헌영;우진춘;황의진
    • 분석과학
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    • 제15권6호
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    • pp.580-583
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    • 2002
  • New approach is developed employing the overall uncertainty obtained from multiple measurements to evaluate the statistical significance for the difference between a given reference value and its measured value determined in a lab. The overall uncertainty is determined by separate combinations of the uncertainties arising from systematic and random effects. It is shown that the uncertainty term in regular t-test can be underestimated by n measurements.

리스테리아균의 특성분석을 위한 Molecular Typing 방법의 상호보완 (Enhanced Discrimination of Listeria spp. Using RAPD Fingerprinting Complemented by Ribotyping-PCR)

  • 임형근;홍종해;박경진;최원상
    • 생명과학회지
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    • 제13권5호
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    • pp.699-704
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    • 2003
  • 리스테리아를 보다 효과적으로 typing할 수 있는 방법을 찾기 위해 표준균주 13종을 대상으로 하여 RAPD, ERIC (Enterobacterial repetitive intergenic consensus) fingerprinting, ribotyping-PCR의 분리력을 비교해 보았다. DG107 (primer 6) 또는 DG122 (Lis 11) primer를 이용한 RAPD의 경우 11가지의 유형으로 분류되는 반면, ERIC fingerprinting은 9가지, ribotyping-PCR은 7가지씩의 유형을 보였다. 그러나 2가지 primer를 이용하여 각각 행한 RAPD 결과를 종합하거나, DG122를 이용한 RAPD와 ribotyping-PCR의 결과를 종합할 경우 13가지의 유형으로 모두 분리할 수 있었다.

토양 유기물 분리 처리 방법이 비친수성 오염물질 흡착에 미치는 영향

  • 정상조;챨리 월스
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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    • pp.42-45
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    • 2005
  • Accurate prediction of the fate and transport of contaminants in soils and sediments is very Important to environmental risk assessment and effective remediation of contaminated soils and sediments. The fate and transport of contaminants in subsurface are affected by geosorbents, especially carbonaceous materials including black carbon. Various physical and chemical treatment methods have been developed to separate different kinds of carbonaceous materials from soils and sediments. However, the effects of these separation methods on the properties of remaining carbonaceous materials including sorption capacity and linearity are unclear. The objective of this study is to determine if the chemical and thermal treatment methods previously used to separate different carbonaceous material fractions affect the properties of carbonaceous materials including longer term sorption capacity of hydrophobic organic contaminants. The results indicate that treatments with hydrochloric acid (HCl)/hydrofluoric acid (HF), trifluoroacetic acid (TFA), sodium hydroxide (NaOH) may not affect the sorption capacity of black carbon reference materials such as char and soot, however, treatments with acid dichromate $(K_2Cr_2O_7/H_2SO_4)$ and heat $(375^{\circ}C)$ for 24 hours in sufficient of oxygen) decrease the sorption capacity of them. The results of longer term sorption isotherm indicate that 2 days might be enough for trichloroethene (TCE) to equilibrate apparently with treated black carbon reference materials. The results suggest that acid dichromate and heat treatments may not appropriate method to investigate sorption properties of black carbon in soils and sediments.

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Range-Scaled 14b 30 MS/s Pipeline-SAR Composite ADC for High-Performance CMOS Image Sensors

  • Park, Jun-Sang;Jeong, Jong-Min;An, Tai-Ji;Ahn, Gil-Cho;Lee, Seung-Hoon
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제16권1호
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    • pp.70-79
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    • 2016
  • This paper proposes a low-power range-scaled 14b 30 MS/s pipeline-SAR composite ADC for high-performance CIS applications. The SAR ADC is employed in the first stage to alleviate a sampling-time mismatch as observed in the conventional SHA-free architecture. A range-scaling technique processes a wide input range of 3.0VP-P without thick-gate-oxide transistors under a 1.8 V supply voltage. The first- and second-stage MDACs share a single amplifier to reduce power consumption and chip area. Moreover, two separate reference voltage drivers for the first-stage SAR ADC and the remaining pipeline stages reduce a reference voltage disturbance caused by the high-speed switching noise from the SAR ADC. The measured DNL and INL of the prototype ADC in a $0.18{\mu}m$ CMOS are within 0.88 LSB and 3.28 LSB, respectively. The ADC shows a maximum SNDR of 65.4 dB and SFDR of 78.9 dB at 30 MS/s, respectively. The ADC with an active die area of $1.43mm^2$ consumes 20.5 mW at a 1.8 V supply voltage and 30 MS/s, which corresponds to a figure-of-merit (FOM) of 0.45 pJ/conversion-step.

깊이 정보를 이용한 영역분할 기반의 다시점 영상 조명보상 기법 (Illumination Compensation Algorithm based on Segmentation with Depth Information for Multi-view Image)

  • 강근호;고민수;유지상
    • 한국정보통신학회논문지
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    • 제17권4호
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    • pp.935-944
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    • 2013
  • 본 논문에서는 영상 분할을 이용한 다시점 영상의 조명보상 기법을 제안한다. 제안하는 기법에서는 깊이 정보를 이용하여 일정 거리에 따라 참조 영상의 깊이 영상을 레이어로 분리한다. 분리된 레이어에서 서로 다른 객체를 분리하기 위하여 각 레이어에 레이블링 과정을 수행한다. 레이블링 된 참조 영상의 깊이 영상은 3D 워핑 기법을 통하여 왜곡 영상의 시점으로 변환되고 레이블링 된 영역을 찾아 히스토그램을 이용한 조명 보상을 각 영역에서 독립적으로 수행한다. 3D 워핑으로 발생하는 가려짐 영역은 전역적인 방법을 이용하여 보상하게 된다. 다양한 실험을 통해 제안하는 기법으로 조명보상 전처리를 수행한 다시점 영상의 부호화 효율이 향상되는 것을 확인할 수 있었다.

The Efficiency of Long Short-Term Memory (LSTM) in Phenology-Based Crop Classification

  • Ehsan Rahimi;Chuleui Jung
    • 대한원격탐사학회지
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    • 제40권1호
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    • pp.57-69
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    • 2024
  • Crop classification plays a vitalrole in monitoring agricultural landscapes and enhancing food production. In this study, we explore the effectiveness of Long Short-Term Memory (LSTM) models for crop classification, focusing on distinguishing between apple and rice crops. The aim wasto overcome the challenges associatedwith finding phenology-based classification thresholds by utilizing LSTM to capture the entire Normalized Difference Vegetation Index (NDVI)trend. Our methodology involvestraining the LSTM model using a reference site and applying it to three separate three test sites. Firstly, we generated 25 NDVI imagesfrom the Sentinel-2A data. Aftersegmenting study areas, we calculated the mean NDVI values for each segment. For the reference area, employed a training approach utilizing the NDVI trend line. This trend line served as the basis for training our crop classification model. Following the training phase, we applied the trained model to three separate test sites. The results demonstrated a high overall accuracy of 0.92 and a kappa coefficient of 0.85 for the reference site. The overall accuracies for the test sites were also favorable, ranging from 0.88 to 0.92, indicating successful classification outcomes. We also found that certain phenological metrics can be less effective in crop classification therefore limitations of relying solely on phenological map thresholds and emphasizes the challenges in detecting phenology in real-time, particularly in the early stages of crops. Our study demonstrates the potential of LSTM models in crop classification tasks, showcasing their ability to capture temporal dependencies and analyze timeseriesremote sensing data.While limitations exist in capturing specific phenological events, the integration of alternative approaches holds promise for enhancing classification accuracy. By leveraging advanced techniques and considering the specific challenges of agricultural landscapes, we can continue to refine crop classification models and support agricultural management practices.

Modeling and Synchronizing Motion Control of Twin-servo System

  • Kim, Bong-Keun;Chung, Wan-Kyun;Lee, Kyo-Beum;Song, Joong-Ho;Ick Choy
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1999년도 제14차 학술회의논문집
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    • pp.302-305
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    • 1999
  • Twin-servo mechanism is used to increase the payload capacity and speed of high precision motion control system. In this paper, we propose a robust synchronizing motion control algorithm to cancel out the skew motion of twin-servo system caused by different dynamic characteristics of two driving systems and the vibration generated by high accelerating and decelerating motions. This proposed control algorithm consists of separate feedback motion control algorithm of each driving system and skew motion compensation algorithm between two systems. Robust model reference tracking controller is proposed as a separate motion controller and its disturbance attenuation property is shown. For the synchronizing motion, skew motion compensation algorithm is designed, and the stability of whole Closed loop system is proved based on passivity theory.

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침입자 검출을 위한 보안 시스템에서의 참고영상 갱신 방안에 관한 연구 (Reference Image Update on the Security System for the Moving Object Detection)

  • 안용학
    • 융합보안논문지
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    • 제2권2호
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    • pp.99-108
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    • 2002
  • 본 연구에서는 실제 야외 환경에서 얻어지는 영상열에서 차영상 기법을 이용하여 침입자를 감지하는 보안 시스템에서 필요한 참고영상 갱신 방안을 제안한다. 제안된 방법은 선별적 참고영상 갱신방법의 영역판별 오류에 의한 영향을 미디언 필터링(Median Filtering)을 이용하여 최소화하였다. 먼저, 연속적으로 들어오는 입력영상과 참고영상의 차영상을 얻어 상향조정된 임계치를 이용하여 이동물체 영역이 제거된 선별적인 임시영상을 생성한다. 그리고 조명의 변화나 이동물체의 외곽에 반응하는 배경물체의 오류를 제거하기 위해 미디언 필터링을 수행함으로써 불규칙적으로 발생하는 밝기변화에 적응할 수 있게 한다. 제안된 방법을 실제 야외 상황에서 얻은 다양한 영상열에 적용한 결과 기존의 참고영상 갱신방법보다 주위 잡음과 무관한 참고영상을 생성한 수 있었다.

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