• 제목/요약/키워드: image sensing

검색결과 2,222건 처리시간 0.028초

반도체 capacitive 지문 센서 및 이미지 합성 방법 (Semiconductor Capacitive Fingerprint Sensor and Image Synthesis Technique)

  • 이정우;민동진;김원찬
    • 전자공학회논문지D
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    • 제36D2호
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    • pp.62-70
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    • 1999
  • 본 논문에서는 저 비용, 고해상도 반도체 지문 센서칩에 대하여 논한다. 제작된 테스트 칩은 $64{\times}256$ 센싱 셀(sensing cell)로 구성되어 있으며, 칩의 크기는 $2.7mm{\times}10.8mm$이다. sensing cell 내부에서 일어나는 전하 재분포를 감지하는 새로운 방식을 이용하여 내부의 기생 캐패시턴스의 영향을 효과적으로 제거하는 방법을 제안하였다. 제안하는 방법은 센싱 셀의 감지 능력을 키우므로 센싱 셀의 크기를 줄일 수 있고, 따라서 고해상도의 이미지를 추출할 수 있다. 표준 0.6${\mu}m$ CMOS 공정을 이용하여 제작된 칩은 600dpi의 해상도를 가지는 지문 이미지를 추출한다. 제조 단가를 낮추기 위하여 지문의 부분 이미지들로부터 전체 지문 이미지를 얻어내는 이미지 합성 방법의 가능성과 문제점에 대해서도 논의하였다.

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Ground-based Remote Sensing Technology for Precision Farming - Calibration of Image-based Data to Reflectance -

  • Shin B.S.;Zhang Q.;Han S.;Noh H.K.
    • Agricultural and Biosystems Engineering
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    • 제6권1호
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    • pp.1-7
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    • 2005
  • Assessing health condition of crop in the field is one of core operation in precision fanning. A sensing system was proposed to remotely detect the crop health condition in terms of SP AD readings directly related to chlorophyll contents of crop using a multispectral camera equipped on ground-based platform. Since the image taken by a camera was sensitive to changes in ambient light intensity, it was needed to convert gray scale image data into reflectance, an index to indicate the reflection characteristics of target crop. A reference reflectance panel consisting of four pieces of sub-panels with different reflectance was developed for a dynamic calibration, by which a calibration equation was updated for every crop image captured by the camera. The system performance was evaluated in a field by investigating the relationship between com canopy reflectance and SP AD values. The validation tests revealed that the com canopy reflectance induced from Green band in the multispectral camera had the most significant correlation with SPAD values $(r^2=0.75)$ and NIR band could be used to filter out unwanted non-crop features such as soil background and empty space in a crop canopy. This research confirmed that it was technically feasible to develop a ground-based remote sensing system for assessing crop health condition.

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수정 이방성 분산 복원을 이용한 영상 분류 (Image Classification Using Modified Anisotropic Diffusion Restoration)

  • 이상훈
    • 대한원격탐사학회지
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    • 제19권6호
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    • pp.479-490
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    • 2003
  • This study proposed a modified anisotropic diffusion restoration for image classification. The anisotropic diffusion restoration uses a probabilistic model based on Markov random field, which represents geographical connectedness existing in many remotely sensed images, and restores them through an iterative diffusion processing. In every iteration, the bonding-strength coefficient associated with the spatial connectedness is adaptively estimated as a function of brightness gradient. The gradient function involves a constant called "temperature", which determines the amount of discontinuity and is continuously decreased in the iterations. In this study, the proposed method has been extensively evaluated using simulated images that were generated from various patterns. These patterns represent the types of natural and artificial land-use. The simulated images were restored by the modified anisotropic diffusion technique, and then classified by a multistage hierarchical clustering classification. The classification results were compared to them of the non-restored simulation images. The restoration with an appropriate temperature considerably reduces error in classification, especially for noisy images. This study made experiments on the satellite images remotely sensed on the Korean peninsula. The experimental results show that the proposed approach is also very effective on image classification in remote sensing.

MRU-Net: A remote sensing image segmentation network for enhanced edge contour Detection

  • Jing Han;Weiyu Wang;Yuqi Lin;Xueqiang LYU
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제17권12호
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    • pp.3364-3382
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    • 2023
  • Remote sensing image segmentation plays an important role in realizing intelligent city construction. The current mainstream segmentation networks effectively improve the segmentation effect of remote sensing images by deeply mining the rich texture and semantic features of images. But there are still some problems such as rough results of small target region segmentation and poor edge contour segmentation. To overcome these three challenges, we propose an improved semantic segmentation model, referred to as MRU-Net, which adopts the U-Net architecture as its backbone. Firstly, the convolutional layer is replaced by BasicBlock structure in U-Net network to extract features, then the activation function is replaced to reduce the computational load of model in the network. Secondly, a hybrid multi-scale recognition module is added in the encoder to improve the accuracy of image segmentation of small targets and edge parts. Finally, test on Massachusetts Buildings Dataset and WHU Dataset the experimental results show that compared with the original network the ACC, mIoU and F1 value are improved, and the imposed network shows good robustness and portability in different datasets.

오픈소스 클라우드 플랫폼 OpenStack 기반 위성영상분석처리 서비스 시험구현 (Testing Implementation of Remote Sensing Image Analysis Processing Service on OpenStack of Open Source Cloud Platform)

  • 강상구;이기원
    • 한국지리정보학회지
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    • 제16권4호
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    • pp.141-152
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    • 2013
  • 2013년 현재 클라우드(Cloud) 컴퓨팅 서비스는 정보통신기술분야의 핵심 기술 동향 중 하나로서 이에 관련된 기술이나 사업 응용 분야가 계속 발전, 확대되고 있다. 이러한 서비스를 개발할 수 있는 기반 요소인 클라우드 플랫폼 중에 하나인 OpenStack은 오픈소스 기반으로 몇 가지의 내부 기술 요소로 이루어져 있고, 서비스 목적에 따라 상업적 플랫폼에 의존하지 않고도 독자적인 공개 및 비공개 클라우드 컴퓨팅 환경을 구축할 수 있는 환경을 제공한다. 이번 연구에서는 위성영상정보 분석처리 시스템을 시범적인 클라우드 서비스 모델로 설정하여 OpenStack을 기반으로 비공개 클라우드 컴퓨팅 환경으로 설계, 구축하는 사례를 제시하고자 하였다. 구현된 서비스는 세부적으로 인스턴스 서버, 웹 서비스, 모바일 앱으로 구분하였다. 인스턴스 서버는 실제 위성영상정보 분석처리, 데이터베이스 등의 기능을 제공하고, 웹 서비스는 사용자로부터 위성영상정보를 저장 및 관리하는 기능을 제공한다. 한편 모바일 앱은 위성영상정보의 시각화 및 분석처리 요청 등의 기능을 수행한다.

저상관도 측정치와 DCT를 이용한 압축센싱 기반 영상 획득 알고리듬 (A Compressive Sensing Based Imaging Algorithm Using Incoherent Measurements and DCT)

  • 김시현
    • 한국정보통신학회논문지
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    • 제20권10호
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    • pp.1961-1966
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    • 2016
  • 최근 활발히 연구되고 있는 압축센싱 (compressive sensing) 이론에 따르면 나이퀴스트 주파수보다 적은 샘플율으로도 원 신호를 충실히 복원할 수 있음이 알려져 있다. 압축, 전송, 저장 등의 여러 분야에서 압축센싱 방법을 적용하려는 시도가 꾸준히 이어지고 있다. 특히 4K, 8K 등으로 요구되는 화소수가 제곱의 형태로 증가되는 영상처리 분야에서는 압축센싱에 기대하는 바가 크다. 본 논문에서는 압축센싱 기법을 적용한 영상의 획득 알고리듬을 제안한다. 영상의 일반적인 특성을 활용하여 높은 에너지 압축 성능을 가지는 DCT와 저상관도의 특성을 갖는 Noiselet 변환을 결합하여 영상 획득 과정을 구성한다. 원 영상은 2차 콘 프로그램 (SOCP)을 풀어 복원할 수 있다. 여러 영상에 대해 획득 및 복원 성능을 측정 및 비교하였으며 제안된 알고리듬이 우수한 복원 성능을 보임을 알 수 있다.

Detection of The Pine Trees Damaged by Pine Wilt Disease using High Resolution Satellite and Airborne Optical Imagery

  • Lee, Seung-Ho;Cho, Hyun-Kook;Lee, Woo-Kyun
    • 대한원격탐사학회지
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    • 제23권5호
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    • pp.409-420
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    • 2007
  • Since 1988, pine wilt disease has spread over rapidly in Korea. It is not easy to detect the damaged pine trees by pine wilt disease from conventional remote sensing skills. Thus, many possibilities were investigated to detect the damaged pines using various kinds of remote sensing data including high spatial resolution satellite image of 2000/2003 IKONOS and 2005 QuickBird, aerial photos, and digital airborne data, too. Time series of B&W aerial photos at the scale of 1:6,000 were used to validate the results. A local maximum filtering was adapted to determine whether the damaged pines could be detected or not at the tree level from high resolution satellite images, and to locate the damaged trees. Several enhancement methods such as NDVI and image transformations were examined to find out the optimal detection method. Considering the mean crown radius of pine trees, local maximum filter with 3 pixels in radius was adapted to detect the damaged trees on IKONOS image. CIR images of 50 cm resolution were taken by PKNU-3(REDLAKE MS4000) sensor. The simulated CIR images with resolutions of 1 m, 2 m, and 4 m were generated to test the possibility of tree detection both in a stereo and a single mode. In conclusion, in order to detect the pine tree damaged by pine wilt disease at a tree level from satellite image, a spatial resolution might be less than 1 m in a single mode and/or 1 m in a stereo mode.

Reducing Spectral Signature Confusion of Optical Sensor-based Land Cover Using SAR-Optical Image Fusion Techniques

  • ;Tateishi, Ryutaro;Wikantika, Ketut;M.A., Mohammed Aslam
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.107-109
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    • 2003
  • Optical sensor-based land cover categories produce spectral signature confusion along with degraded classification accuracy. In the classification tasks, the goal of fusing data from different sensors is to reduce the classification error rate obtained by single source classification. This paper describes the result of land cover/land use classification derived from solely of Landsat TM (TM) and multisensor image fusion between JERS 1 SAR (JERS) and TM data. The best radar data manipulation is fused with TM through various techniques. Classification results are relatively good. The highest Kappa Coefficient is derived from classification using principal component analysis-high pass filtering (PCA+HPF) technique with the Overall Accuracy significantly high.

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압축센싱을 위한 필터선택 비교 (Comparison of Filter Selection for Compressed Sensing)

  • Pham, Phuong Minh;Shim, Hiuk Jae;Jeon, Byeungwoo
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 2012년도 추계학술대회
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    • pp.188-190
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    • 2012
  • Compressed Sensing (CS) has been developed for several years. Among many CS algorithms for image, the Block-based Compressed Sensing with Smoothed Projected Landweber (BCS-SPL) demonstrates its excellent performance in low-complexity and near-optimal reconstruction. Several noise filtering algorithms of image reconstruction have been introduced such as the Wiener or the median filters, etc. In general, each filter has its own advantages and disadvantages depending on specific coding scheme. In this paper, we show that reconstruction performance can be varied according to the choice of filter. When a sub-rate value is changed, different filter causes different effect as well. Concerning the sub-rate, an inner filter can be chosen to improve the reconstructed image quality.

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Landscape pattern analysis from IKONOS image data by wavelet and semivariogram method

  • Danfeng, Sun;Hong, Li
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1209-1211
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    • 2003
  • The wavelet and semivariogram analysis method are used to identify the city landscape and farmland landscape pattern on the 1m resolution IKONOS images. The results prove that wavelet method is a potential way for landscape pattern analysis. Compared to semivariogram analysis, Wavelet analysis can not only detect the overall spatial pattern, but also find multi-scale and direction structures. In this experiment, the wavelet analysis results indicate: (1) the city landscape image is mainly composed of three level structures whose spatial pattern characters appear at 2m, 16m, 128m and 256m accordingly; (2) the farmland landscape is mainly two scale spatial patterns appearing at the 2m, 128m and 256m. IKONOS Remote sensing, with the high spatial and spectral information, is a powerful tool that can use in many ecological systems research and sustainable management.

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