• 제목/요약/키워드: Sensing Area

검색결과 2,138건 처리시간 0.024초

Selection of Monitoring Nodes to Maximize Sensing Area in Behavior-based Attack Detection

  • Chong, Kyun-Rak
    • 한국컴퓨터정보학회논문지
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    • 제21권1호
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    • pp.73-78
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    • 2016
  • In wireless sensor networks, sensors have capabilities of sensing and wireless communication, computing power and collect data such as sound, movement, vibration. Sensors need to communicate wirelessly to send their sensing data to other sensors or the base station and so they are vulnerable to many attacks like garbage packet injection that cannot be prevented by using traditional cryptographic mechanisms. To defend against such attacks, a behavior-based attack detection is used in which some specialized monitoring nodes overhear the communications of their neighbors(normal nodes) to detect illegitimate behaviors. It is desirable that the total sensing area of normal nodes covered by monitoring nodes is as large as possible. The previous researches have focused on selecting the monitoring nodes so as to maximize the number of normal nodes(node coverage), which does not guarantee that the area sensed by the selected normal nodes is maximized. In this study, we have developed an algorithm for selecting the monitoring nodes needed to cover the maximum sensing area. We also have compared experimentally the covered sensing areas computed by our algorithm and the node coverage algorithm.

원격탐사자료의 환경영향평가 활용을 위한 기초연구 (Preliminary Study for an Application to Environmental Impact Assessment of Remote Sensing Data)

  • 문현생;김명진;강인구;방규철
    • 환경영향평가
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    • 제4권1호
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    • pp.59-64
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    • 1995
  • Environmental Impact Assesment(EIA) is composed of various procedures, such as screening, scoping, inventory survey, prediction, assessment, mitigation measure, alternative assessment, and post management. Remote sensing introduced lately begins to be applied ecosystem and land use in inventory survey and assessment of EIA. This study explains on land use classification, buffering analysis of residential area, and overlaying analysis of odor predictive data with residential area for application to EIA with remote sensing data. Residential area extracted from land use classification of remote sensing provides effectively buffering analysis of residential area in selection of landfill site with GIS. It could assess also residential effect to an offensive odor by overlaying analysis. Application methods in EIA should be enlarged to assess effectively.

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ITO Extended Gate Reduced Graphene Oxide Field Effect Transistor For Proton Sensing Application

  • Truong, Thuy Kieu;Nguyen, T.N.T.;Trung, Tran Quang;Son, Il Yung;Kim, Duck Jin;Jung, Jin Heak;Lee, N.E.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
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    • pp.653-653
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    • 2013
  • In this study, ITO extended gate reduced graphene oxide field effect transistor (rGO FET) was demonstrated as a transducer for a proton sensing application. In this structure, the sensing area is isolated from the active area of the device. Therefore, it is easy to deposit or modify the sensing area without affecting on the device performance. In this case, the ITO extended gate was used as a gate electrode as well as a proton sensing material. The proton sensing properties based on the rGO FET transducer were analyzed. The rGO FET device showed a high stability in the air ambient with a TTC encapsulation layer for months. The device showed an ambipolar characteristic with the Dirac point shift with varying the pH solutions. The sensing characteristics have offered the potential for the ion sensing application.

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A New Method of Remote Sensing Image Fusion Based on Modified Kohonen Networks

  • Shuhe, Zhao;Xiuwan, Chen;Junfeng, Chen;Yinghai, Ke
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1337-1339
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    • 2003
  • In this article, a new remote sensing image fusion model based on modified Kohonen networks is given. And a new fusion rule based on modified voting rule was established. Select Shaoxing City as the study site, located at Zhejiang Province, P.R.China. The fusion experiment between Landsat TM data (30m) and IRS-C Pan data (5.8m) was performed using the given fusion method. The fusion results show that the new method can gain better result in apply ing to the lower hill area, and the whole classification accuracy was 10% higher than the basic Kohonen method. The confusion between the woodlands and the waterbodies was also diminished.

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한국기상학회 원격탐사 분야 학술 발전 현황 (A Progress Status of Remote Sensing in the Korean Meteorological Society)

  • 안명환;김준;이규원;김상우
    • 대기
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    • 제33권2호
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    • pp.197-222
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    • 2023
  • Remote sensing becomes a new and core framework for the atmospheric sciences and closely related areas concerning with the ever-changing global environmental status. However, remote sensing in the Korea Meteorological Society is relatively new, where the first relevant paper is appeared in 1983, as well as is an area with relatively limited number of research groups. Here, we review and summarize some of the key progress in this area within Korea Meteorological Society focusing on the areas of satellite, radar, and ground based remote sensing such as lidar, spectrometer and sun photometer. Overall, the area is shown to have the most significant progress occur along with the acquisition of the key infra structures such as the COMS (Communication, Ocean and Meteorological Satellite) and S-band radar system led by Korea Meteorological Administration in early 2000. After that, the area has quickly developed into a status playing important roles to lead and support the overall activities in the atmospheric measurements. It is expected that the importance and role of the remote sensing will increase in the coming years.

Compressed Sensing 기법을 이용한 Dynamic MR Imaging (Compressed Sensing Based Dynamic MR Imaging: A Short Survey)

  • 정홍;예종철
    • 대한전자공학회논문지SP
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    • 제46권5호
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    • pp.25-31
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    • 2009
  • Compressed sensing은 기존의 Nyquist sampling 이론에 기반을 두었던 dynamic MRI에서의 시 공간 해상도의 제한을 획기적으로 향상시킴으로써, 최근 몇 년 사이, MR reconstruction 분야에서 가장 큰 이슈가 되고 있는 연구주제이다. Dynamic MRI 는 대부분 시간방향의 redundancy 가 매우 크므로, 쉽게 sparse 변환이 가능하다. 따라서 sparsity를 기본 조건으로 하는 compressed sensing은 거의 모든 dynamic MRI 에 대해 효과적으로 적용될 수 있다. 본 review 페이퍼에서는 최근 compressed sensing 에 기반을 두거나 영상의 sparsity를 이용하여 개발된 dynamic MR imaging algorithm 들을 간략히 소개하고, 비교 분석함으로써, compressed sensing과 같은 새로운 접근 방식의 dynamic MRI가 실제 임상에서 가져다 줄 발전 가능성을 제시한다.

원격탐사자료에 의한 해남지역 비금속광상 및 관련 특성 추출을 위한 연구 (A Study on Extraction of Non-metallic Ore Deposits from Remote Sensing Data of the Haenam Area)

  • 박인석;박종남
    • 대한원격탐사학회지
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    • 제8권2호
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    • pp.105-123
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    • 1992
  • A study was made on the feature extraction for non-metallic one deposits and their related geology using the Remote Sensing and Airborne Radiometric data. The area chosen is around the Haenam area, where dickite and Quarzite mines are distributed in. The geology of the area consists mainly of Cretaceous volcanics and PreCambrian metamorphic. The methods applied are study on the reflectance characteristics of minerals and rocks sampled in the study area, and the feature extraction extraction of histogram normalized images for Landsat TM and Airborne Radiometric data, and finally evaluation of applicability of some useful pattern recognition techniques for regional lithological mapping. As a result, reflectances of non-metallic minerals are much higher than rock samples in the area. However, low grade dickites are slightly higher than rock samples, probably due to their greyish colour and also their textural features which may scatter the reflectance and may be capable of capturing much hychoryl ions. The reflectances of rock samples may depend on the degree of whiteness of samples. The outcrops or mine dumps in the study area were most effectively extracted on the histogram normalized image of TM Band 1, 2 and 3, due to their high reflectivity. The Masking technique using the above bands may be the most effective and the natural colour composite may provide some success as well. The colour composite image of PCA may also be effective in extracting geological features, and airborne radiometric data may be useful to some degree as an complementary tool.

Study on the Urban Heat Island(UHI) using Remote Sensing data

  • Kyung, H.M.;Kim, Y.S.;Park, K.W.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.846-848
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    • 2003
  • Analysis of UHI in Busan region using Landsat TM data. Between 1987 and 1997 surface temperature increased clearly. Land usage of Busan is construed that instigate UHI changing into industry and commerce area. Also, intensity of UHI in surface temperature appeared strongly in industrial area and business area. On the contrary, residential area, mountain area, suburb area did not appear strongly.

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원격 탐사 자료와 현장 조사 자료를 이용한 기저면적 예측 지도 제작 (Basal Area Mapping using Remote Sensing and Ecological Data)

  • 이정빈;;허준
    • 대한원격탐사학회지
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    • 제24권6호
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    • pp.621-629
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    • 2008
  • 인도의 Tamil Nadu 지역을 대상지역으로 선택하여 Landsat ETM+ 영상과 현장 조사 자료(기저면적, 개체 수, 종의 수)를 취득하였다. 취득된 자료를 통하여 (1) 영상의 분류, (2) 식생지수 영상의 추출(NDVI, Tasseled Cap 토양명도, 녹색식생, 토양습도), (3) 가장 상관관계가 높은 결과를 보인 NDVI와 기저면적(Basal area)을 이용한 식생다양성 분포 예측 지도 제작이 이루어 졌다. 기저면적과 NDVI가 가장 높은 상관관계를 가지며 대상지역 영상분류 결과 69%정도의 정확도를 보였다.

중첩 초음파 센서 링의 장애물 탐지 성능 지표 비교 분석 (Comparative Analysis on Performance Indices of Obstacle Detection for an Overlapped Ultrasonic Sensor Ring)

  • 김성복;김현빈
    • 제어로봇시스템학회논문지
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    • 제18권4호
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    • pp.321-327
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    • 2012
  • This paper presents a comparative analysis on three different types of performance indices of obstacle detection for an overlapped ultrasonic sensor ring. Due to beam overlap, the entire sensing zone of each ultrasonic sensor can be divided into three smaller sensing subzones, which leads to significant reduction of positional uncertainty in obstacle detection. First, the positional uncertainty in obstacle detection is expressed in terms of the area of a sensing subzone, and type 1 performance index is then defined as the area ratio of side and center sensing subzones. Second, based on the area of a sensing subzone, type 2 performance index is defined taking into account the size of the entire range of obstacle detection as well as the degree of the positional uncertainty in obstacle detection. Third, the positional uncertainty in obstacle detection is now expressed in terms of the length of the uncertainty arc spanning a sensing subzone, and type 3 performance index is then defined as the average value of the uncertainty arc lengths over the entire range of obstacle detection. Fourth, using a commercial low directivity ultrasonic sensor, the changes of three different performance indices depending on the parameter of an overlapped ultrasonic sensor ring are examined and compared.