• 제목/요약/키워드: Sensing uncertainty

검색결과 135건 처리시간 0.033초

풍력자원평가용 윈드큐브 라이다와 씬텍 소다의 비교.검증 - 잠실 원격탐사 캠페인 (Comparative Validation of WindCube LIDAR and Scintec SODAR for Wind Resource Assessment - Remote Sensing Campaign at Jamsil)

  • 김현구;김동혁;전완호;최현정
    • 신재생에너지
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    • 제7권2호
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    • pp.43-50
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    • 2011
  • The only practical way to measure wind resource at high-altitude over 100 m above ground for a feasibility study on a high-rise building integrated wind turbine might be ground-based remote sensing. The remote-sensing campaign was performed at a 145 m-building roof in Jamsil where is a center of metropolitan city Seoul. The campaign aimed uncertainty assessment of Leosphere WindCube LIDAR and Scintec MPAS SODAR through a mutual comparison. Compared with LIDAR, the data availability of SODAR was about 2/3 at 550 m altitude while both showed over 90% under 400 m, and it is shown that the data availability decrease may bring a distortion of statistical analysis. The wind speed measurement of SODAR was fitted to a slope of 0.92 and $R^2$ of 0.90 to the LIDAR measurement. The relative standard deviation of wind speed difference and standard deviation of wind direction difference were evaluated to be 30% and 20 degrees, respectively over the whole measurement heights.

A COMPARISON OF OBJECTED-ORIENTED AND PIXELBASED CLASSIFICATION METHODS FOR FUEL TYPE MAP USING HYPERION IMAGERY

  • Yoon, Yeo-Sang;Kim, Yong-Seung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.297-300
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    • 2006
  • The knowledge of fuel load and composition is important for planning and managing the fire hazard and risk. However, fuel mapping is extremely difficult because fuel properties vary at spatial scales, change depending on the seasonal situations and are affected by the surrounding environment. Remote sensing has potential of reduction the uncertainty in mapping fuels and offers the best approach for improving our abilities. This paper compared the results of object-oriented classification to a pixel-based classification for fuel type map derived from Hyperion hyperspectral data that could be enable to provide this information and allow a differentiation of material due to their typical spectra. Our methodological approach for fuel type map is characterized by the result of the spectral mixture analysis (SMA) that can used to model the spectral variability in multi- or hyperspectral images and to relate the results to the physical abundance of surface constitutes represented by the spectral endmembers. Object-oriented approach was based on segment based endmember selection, while pixel-based method used standard SMA. To validate and compare, we used true-color high resolution orthoimagery

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원자현미경용 XY 스캐너의 아베 오차 최소화를 위한 최적 설계 및 원자 현미경의 측정 불확도 평가 (Optimal design of a flexure hinge-based XY AFM scanner for minimizing Abbe errors and the evaluation of measuring uncertainty of AFM system)

  • 김동민;이동연;권대갑
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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    • pp.1438-1441
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    • 2005
  • To establish of standard technique of nano-length measurement in 2D plane, new AFM system has been designed. In this system, measurement uncertainty is dominantly affected by the Abbe error of XY scanning stage. No linear stage is perfectly straight; in other words, every scanning stage is subject to tilting, pitch and yaw motion. In this paper, an AFM system with minimum offset of XY sensing is designed. And XY scanning stage is designed to minimize rotation angle because Abbe errors occur through the multiply of offset and rotation angle. To minimize the rotation angle optimal design has performed by maximizing the stiffness ratio of motion direction to the parasitic motion direction of each stage. This paper describes the design scheme of full AFM system, especially about XY stage. Full range of fabricated XY scanner is $100um\times{100um}$. And tilting, pitch and yaw motion are measured by autocollimator to evaluate the performance of XY stage. Using this AFM system, 3um pitch specimen was measured. As a result, the uncertainty of total system has been evaluated.

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PROJECTION OF TRAJECTORY FOR SUPPORTING UNCERTAINTY FUTURE TIME OF MOVING OBJECT

  • Won Ho-Gyeong;Jung Young Jin;Lee Yang Koo;Park Mi;Kim Hak-cheol;Ryu Keun Ho
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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    • pp.72-75
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    • 2005
  • Uncertainty of objects in Moving Object Database is a coherent property. It has been discussed in a lot of researches on modelling and query processing. The previous studies assume that uncertain future time is determined through utilizing recent speed and direction of vehicles. This method is simple and useful for estimating the time of the near future location. However, it is not appropriate when we estimate the time of the far future location. Therefore, in this paper, we propose a concept of planned route. It is used to estimate uncertain future time, which has to be located at a given point. If the route of an object is planned beforehand its locations are uncertainly distributed near that route. By a simple projection operation, the probability that a location lies in the planned route is increased. Moreover, we identify the future time of an object based on the speed for passing the route, which is offered via a website.

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XY 스캐너의 아베 오차 최소화를 위한 최적 설계 및 나노 정밀도의 원자 현미경 피치 측정 불확도 평가 (Optimal design of a flexure hinge-based XY AFM scanner for minimizing Abbe errors and the evaluation of pitch measuring uncertainty of a nano-accuracy AFM system)

  • 김동민;이동연;권대갑
    • 한국정밀공학회지
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    • 제23권6호
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    • pp.96-103
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    • 2006
  • To establish of standard technique of nano-length measurement in 2D plane, new AFM system has been designed. In the long range (about several tens of ${\mu}m$), measurement uncertainty is dominantly affected by the Abbe error of XY scanning stage. No linear stage is perfectly straight; in other words, every scanning stage is subject to tilting, pitch and yaw motion. In this paper, an AFM system with minimum offset of XY sensing is designed. And XY scanning stage is designed to minimize rotation angle because Abbe errors occur through the multiply of offset and rotation angle. To minimize the rotation angle optimal design has performed by maximizing the stiffness ratio of motion direction to the parasitic motion direction of each stage. This paper describes the design scheme of full AFM system, especially about XY stage. Full range of fabricated XY scanner is $100{\mu}m\times100{\mu}m$. And tilting, pitch and yaw motion are measured by autocollimator to evaluate the performance of XY stage. As a result, XY scanner can have good performance. Using this AFM system, 3um pitch specimen was measured. The uncertainty of total system has been evaluated. X and Y direction performance is different. X-direction measuring performance is better. So to evaluate only ID pitch length, X-direction scanning is preferable. Its expanded uncertainty(k=2) is $\sqrt{(3.96)^2+(4.10\times10^{-5}{\times}p)^2}$ measured length in nm.

Planning of Compliant Motions for Fixture Loading

  • Yu, Kyeonah
    • Transactions on Control, Automation and Systems Engineering
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    • 제2권1호
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    • pp.62-68
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    • 2000
  • Fixtures are used in almost all phases of machining and assembly to position and hold a part accurately. The class of fixture which consists of 3 locators and 1 clamp(3L/1C) is known as the minimal set that can provide form closure which is a kinematic constraint condition for preventing all planar motions. This type of fixtures has advantages in terms of the number of fixture elements required, the time for clamping, and so on. However it is not widely used in industry because reliable loading scheme has not been reported. In this paper, we propose a method to load the class of 3L/1C fixtures using compliant motions. The planner is developed for synthesizing compliant motions to achieve precise final fixture configuration in the presence of sensing and control uncertainties. A novel approach to eliminate uncertainty in part orientation by adding one extra fixture element called an aligning pin is proposed.

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모델링 불확실성이 존재하는 원격조작기에서 강인 안정을 보장하는 양방향 제어기 설계 (Design of the robust bilateral controller for teleoperators with modeling uncertainties)

  • 이형기;정명진
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.976-979
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    • 1996
  • Teleoperation is the extension of a person's sensing and manipulation capability to a remote location. Teleoperators generally can be modeled as linear transfer function indecently including modeling uncertainty. Modeling uncertainties can make the system unstable and its performance poor. Thus I'm studying about a design framework for a bilateral controller of teleoperator systems with modeling uncertainties. In this paper, a method based on the H$_{\infty}$-optimal control and .mu.-synthesis frameworks are introduced to design a controller for the teleoperator that achieves stability and performance in the presence of the modeling uncertainties..ties.inties.

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다중 스케일 지구통계학을 이용한 원격탐사 자료 기반 주제도의 다운스케일링 (Downscaling of Thematic Maps Based on Remote Sensing Data using Multi-scale Geostatistics)

  • 박노욱
    • 대한원격탐사학회지
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    • 제26권1호
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    • pp.29-38
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    • 2010
  • 높은 공간 해상도의 지상 자료와 상대적으로 저해상도인 원격탐사 자료의 통합을 통한 지표 환경 주제도 작성에서는 이러한 해상도의 차이를 반영한 통합 방법론이 필요하다. 이 연구에서는 상대적으로 저해상도인 원격탐사 자료와 지상 자료로부터 고해상도 주제도 작성과 관련된 다운스케일링을 위한 다중 스케일 지구통계학적 방법론을 적용하였다. 기존 정규 크리깅 시스템을 확장하여 포인트 자료로 간주할 수 있는 지상 자료와 블럭 자료로 간주할 수 있는 원격탐사 자료를 크리깅 시스템에 직접 포함하는 블럭 크리깅 방법론을 이용하였다. 부가적으로 다운스케일링에 따른 불확실성을 묘사하기 위해 블럭 크리깅 기반 시뮬레이션 기법도 함께 이용하였다. SRTM DEM과 MODIS 엽면적 지수 자료의 다운 스케일링 실험 연구를 통해 적용 기법의 적용성을 평가하였다. 두가지 실험 연구 결과, 적용 기법을 통해 효과적으로 상대적으로 고해상도 주제도 생성이 가능함을 확인하였으며, 특히 다중 시뮬레이션 결과는 다운 스케일링된 자료를 입력 자료로 사용하는 GIS 모델에 사용하여 모델 결과의 불확실성 분석에 효율적으로 이용될 수 있을 것으로 기대된다.

OVERVIEW OF KOMPSAT APPLICATION PRODUCT VALIDATION SITE AND THE RELATED ACTIVITIES

  • Lee, Kwang-Jae;Youn, Bo-Yeol;Kim, Duk-Jin;Kim, Youn-Soo
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.122-125
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    • 2007
  • In recent years, there has been an increasing demand for improved accuracy and reliability of Earth Observation Satellite (EOS) data. Most of the data users in the field of remote sensing require understanding of product accuracy and uncertainty. Especially, EOS application products should be validated for practical application in the field. In order to evaluate the availability and applicability of application products, it will be necessary to establish a systematic validation system including techniques, equipments, ground truth data, etc. The Product Validation Site (PVS) for generation and validation of KOMPSAT application products was designed and established with various in-situ equipment and dataset. This paper presents the status of PVS and summarizes some results from experiment studies at PVS.

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위성탐사 이미지에서 혼합화소의 해석에 관한 연구 (An Analysis of Mixed Pixel in the Remote Sensing Image Data)

  • 김진일;박민호;김성천
    • 대한공간정보학회지
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    • 제3권2호
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    • pp.91-100
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    • 1995
  • 본 논문은 위성탐사 이미지의 분류에서 한 화소(SPOT HRV의 밴드 1-3의 경우 $200{\times}20m$)에 포함된 혼합된 정보의 분류를 시도한다. 먼저 기존의 분류기법에서 발생되는 정보의 손실과 혼합화소에 내포된 정보의 불확실성에 대해 알아보고 이를 해결하기 위한 방법으로 피지 시그모이드 함수와 역전파 신경망을 이용한 기법을 제안하며, 이를 실험하고 비교 분석한다.

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