• 제목/요약/키워드: Sensing data

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Dynamic Load-Balancing Algorithm Incorporating Flow Distributions and Service Levels for an AOPS Node

  • Zhang, Fuding;Zhou, Xu;Sun, Xiaohan
    • Journal of the Optical Society of Korea
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    • 제18권5호
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    • pp.466-471
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    • 2014
  • An asynchronous optical packet-switching (AOPS) node with load-balancing capability can achieve better performance in reducing the high packet-loss ratio (PLR) and time delay caused by unbalanced traffic. This paper proposes a novel dynamic load-balancing algorithm for an AOPS node with limited buffer and without wavelength converters, and considering the data flow distribution and service levels. By calculating the occupancy state of the output ports, load state of the input ports, and priorities for data flow, the traffic is balanced accordingly. Simulations demonstrate that asynchronous variant data packets and output traffic can be automatically balanced according to service levels and the data flow distribution. A PLR of less than 0.01% can be achieved, as well as an average time delay of less than 0.46 ns.

Reversible Data Hiding in Block Compressed Sensing Images

  • Li, Ming;Xiao, Di;Zhang, Yushu
    • ETRI Journal
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    • 제38권1호
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    • pp.159-163
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    • 2016
  • Block compressed sensing (BCS) is widely used in image sampling and is an efficient, effective technique. Through the use of BCS, an image can be simultaneously compressed and encrypted. In this paper, a novel reversible data hiding (RDH) method is proposed to embed additional data into BCS images. The proposed method is the first RDH method of its kind for BCS images. Results demonstrate that our approach performs better compared with other state-of-the-art RDH methods on encrypted images.

Study on examination of accuracy of natural environment assessment of satellite data using vegetation index and plant energy

  • Choi, Byung-Yang;Lee, Yang-Jae
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1475-1477
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    • 2003
  • The satellite remote sensing data is good in order to grasp the wide natural environment. The purpose of study is that it examines spectral reflection characteristic and vegetation index by the utilization of the plant energy ( chlorophyll ) for examining the reliability of satellite data and grasps the transition of the natural environment using the result. According to result of analysis, there were NDVI and mutual relationship on chlorophyll, and luminance compensation of NDVI was effective for all area. In vegetation transition, there were no luminance compensation and relation, and there was a decrease of vegetation in area in south and north. The reason was a result by the artificial and natural effect. This analysis is an effective method in order to confirm the change of specific vegetation.

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Effects of Spectral Transformations on Leaf C:N Ratio Inversion with Hyperspectral Data

  • Run-he, SHI;Da-fang, ZHUANG;Qiao-jing, QIAN;Zheng, NIU
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.322-324
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    • 2003
  • Leaf C:N ratio is a new factor in the field of biochemical inversion with hyperspectral data. Effects of common-used spectral transformations including log(R), log(1/R), 1/R, etc. from 400nm to 2490nm on its inversion are compared. Results show that their effects on statistical modeling are not apparent. Continuum removal is used on original reflectance in the range of 2030nm to 2220nm, in which exists an apparent absorption peak due to cellulose, lignin, protein, etc. The effect is distinctive and tends to improve the precision of C:N ratio inversion. Further, it is a robust and physically based transformation.

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Preliminary Biotop Mapping Using High-Resolution Satellite Remote Sensing Data

  • Shin, Dong-Hoon;Lee, Kyoo-Seock
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.856-858
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    • 2003
  • Biotop map can be utilized in the urban area for nature conservation and impact assessment for the proposed activities. High resolution satellite data such as IKONOS and KOMPSAT1-EOS were used to classify land use activities in biotop mapping. After land use classification, field -check was done to survey the wildlife and vegetation. These maps were combined and the boundaries were delineated to produce the biotop map. Within the boundary the characteristics of each polygon were identified, and named. This study was carried out at Daedok Science Town in Taejeon Metropolitan Area. The purpose of this study is to produce the biotop map using high resolution remote sensing data together with other ground data.

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Comparison of Visual Interpretation and Image Classification of Satellite Data

  • Lee, In-Soo;Shin, Dong-Hoon;Ahn, Seung-Mahn;Lee, Kyoo-Seock;Jeon, Seong-Woo
    • 대한원격탐사학회지
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    • 제18권3호
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    • pp.163-169
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    • 2002
  • The land uses of Korean peninsula are very complicated and high-density. Therefore, the image classification using coarse resolution satellite images may not provide good results for the land cover classification. The purpose of this paper is to compare the classification accuracy of visual interpretation with that of digital image classification of satellite remote sensing data such as 20m SPOT and 30m TM. In this study, hybrid classification was used. Classification accuracy was assessed by comparing each classification result with reference data obtained from KOMPSAT-1 EOC imagery, air photos, and field surveys.

Assessing Sea Surface Temperature in the Yellow Sea Using Satellite Remote Sensing Data

  • Lee, Kyoo-seock;Kang, Hee-Sook
    • 대한원격탐사학회지
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    • 제6권1호
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    • pp.39-47
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    • 1990
  • The first Marine Observation Satellite(MOS) was launched by National Space Development Agency of Japan on February 19, 1987, and it is equipped with three sensons covering visible, infrared, and microwave region. One of them is Visible and Thermal Infrared Radiometer(VTIR) whose main objective is to detect the Sea Surface Temperature(SST). The objective of this study was to process the MOS data using Cray-2 supercomputer, and to assess the SST in the Yellow Sea. In order to implement this objective, the linear regression model between the ground truth data and the corresponding digital number of VTIR in MOS was used to establish the relationship. After testing the significance of the regression model, the SST map of the whole Yellow Sea was derived based on the model. The digital SST map representing the study area showed certain pattern about the SST of Yellow Sea in March and April. In conclusion, the VTIR data in MOS is also useful in investigating SST which provides the information about the Yellow Sea water current in the spring.

Cloud computing for handling data from traffic sensing technologies and on-board diagnostics

  • Nkenyereye, Lionel;Jang, Jong-wook
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2014년도 추계학술대회
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    • pp.488-491
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    • 2014
  • Based on a complete understanding research in Information and Communication Technologies (ICT), the Intelligent Transport Systems rapidly build up innovative applications to ensure real time attainment as well remote management of driven information, provide a huge range of services and involve many actors in automotive ecosystem. In this paper, we present an intelligent cloud computing for handling data received from traffic sensing technologies. Transportations technologies applied in ITS have played a great role in collecting data from devices deployed in vehicles and highway infrastructures utilizing broadband wireless technologies to the Cloud. In order to facilitate the interested in automotive industry to use data collected and afford services to the car's owner, a scalable acquisition, access to computing resources and offered services are the primary goal of the proposed cloud computing.

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An Energy Efficient Intelligent Method for Sensor Node Selection to Improve the Data Reliability in Internet of Things Networks

  • Remesh Babu, KR;Preetha, KG;Saritha, S;Rinil, KR
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제15권9호
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    • pp.3151-3168
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    • 2021
  • Internet of Things (IoT) connects several objects with embedded sensors and they are capable of exchanging information between devices to create a smart environment. IoT smart devices have limited resources, such as batteries, computing power, and bandwidth, but comprehensive sensing causes severe energy restrictions, lowering data quality. The main objective of the proposal is to build a hybrid protocol which provides high data quality and reduced energy consumption in IoT sensor network. The hybrid protocol gives a flexible and complete solution for sensor selection problem. It selects a subset of active sensor nodes in the network which will increase the data quality and optimize the energy consumption. Since the unused sensor nodes switch off during the sensing phase, the energy consumption is greatly reduced. The hybrid protocol uses Dijkstra's algorithm for determining the shortest path for sensing data and Ant colony inspired variable path selection algorithm for selecting active nodes in the network. The missing data due to inactive sensor nodes is reconstructed using enhanced belief propagation algorithm. The proposed hybrid method is evaluated using real sensor data and the demonstrated results show significant improvement in energy consumption, data utility and data reconstruction rate compared to other existing methods.

극지 해빙 위성관측을 위한 분석 기술 개발 (Research on Analytical Technique for Satellite Observstion of the Arctic Sea Ice)

  • 김현철;한향선;현창욱;지준화;손영선;이성재
    • 대한원격탐사학회지
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    • 제34권6_2호
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    • pp.1283-1298
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    • 2018
  • 온난화에 의한 이상기후의 징후가 직접적으로 감지되고 있는 북극권에 대한 연구 필요성이 사회적으로 강력히 요구되고 있다. 온난화의 추이를 가장 잘 보여주고 있는 해빙의 변화는 인공위성 원격탐사를 이용하여 추적 감시된다. 극지연구소에서 2017년부터 "북극해빙위성 관측을 위한 기술 개발" 연구를 진행하고 있다. 본 연구는 북극 해빙의 특성 정보를 위성자료로부터 추출하기 위한 다양한 접근법을 이용한 연구를 포함하고 있으며, 북극권 개발에 대비한 '북극 빙권 종합 위성 관측망' 구축에 필수적인 국제 공동 연구 협력도 포함하고 있다. 기후변화 연구와 더불어 북극항로 활용에 대한 기초정보를 제공하고 있는 극지연구소의 북극 원격탐사 연구 소개를 통해 국내 원격탐사 전문가들의 관심과 집중을 부탁하고자 한다. 북극연구에 대한 국제 동향과 국내 정책 배경을 소개하고, 극지연구소에서 연구 수행한 빙권 정보, 특히 한국항공우주연구원과 협동연구를 통해 아리랑위성을 활용한 북극 해빙 관측 연구를 소개한다.