• Title/Summary/Keyword: Sensing data

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REMOTE SENSING OF ATMOSPHERIC FRONTAL DYNAMICS OVER THE OCEAN

  • Levy, Gad;Patoux, Jerome
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.1003-1006
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    • 2006
  • Frontal regions in midlatitude storms exhibit a wide range of behavior, which can be observed by remote sensors. These include decay, strengthening, rotating, and sometimes spawning of new cyclones. Here we refine and apply recent theories of front and frontal wave development to a case of a front clearly observed and analyzed in remote sensing data. By applying innovative analysis techniques to the data we assess the respective roles of ageostrophy, background deformation, and Boundary Layer processes in determining the evolution of the surface front. Our analysis comprises of diagnosis of the terms appearing in the vorticity and divergence equations using remotely sensed observations.

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Object-based Data Fusion Methods using Hyperspectral remote sensing data (초분광 원격탐사자료를 이용한 객체기반 영상융합 기법 연구)

  • Yoon, Yeo-Sang
    • Proceedings of the KSRS Conference
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    • 2007.03a
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    • pp.247-250
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    • 2007
  • 다양한 지구관측위성으로부터 획득된 윈격탐사 자료들은 맴핑 환경모니터링, 재난 관리,도심 모니터링등과 같은 다양한 분야의 정보를 생성하고 분석하는데 많은 잠재력을 가지고 있다. 특별히 고해상도 위성영상의 경우 도심 지역의 다양한 정보를 손쉽게 파악이 가능하며, 이를 기반으로 효과적인 도심 관리 및 시설 투자가 이루어 질 수 있다 그러나 이러한 고해상도 위성영상의 경우 공간 해상력은 매우 좋으나분광해상력 측면에서는 많은 한계를 보이고 있는 단점을 가지고 있다 이를 보완하기 위한 방법으로 고해상도 흑백모드영상과 중${\cdot}$ 저해상도 다중분광영상 혹은 초분광영상간 영상 합성기법을 통해 분광 능력의 향상을 도모하는 기법들이 연구되어져 왔으며보다 최적의 결과를 위한 다양한 알고리즘들이 개발되어 왔다 본 연구에서는 이러한 영상융합결과의 향상을 위한 방법으로 객체기반 단위의 영상합성 방법을 제시하였으벽이 결과와 화소기반 영상융합 결과와의 비교${\cdot}$ 분석도 수행해 보았다. 이를 위해 Landsat-7 ETM+ 혹백영상과 Hyperion 초분광영상을 실험대상으로 선정하여 분석하였으벽 대표적인 영상융합방법인 PCA 융합기법을 활용하였다.

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Improved Coded Mark Inversion for the Passive Radio Frequency Transmission System of the Electronic Time Fuze

  • Xiong, Dong;Zeng, Xiaoping;Zhao, Xiaogang
    • ETRI Journal
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    • v.31 no.3
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    • pp.348-350
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    • 2009
  • To fit the limited volume and power consumption of the passive radio frequency transmission system of the electronic time fuze, an improved coded mark inversion (CMI) is proposed in this letter. From the performance analysis, the energy transmission efficiency of this encoding method is at least 50% higher than that of CMI and NRZ. Finally, the experiment results show that by adopting this improved CMI, the change of DC voltage through magnetic coupling is lower than 0.2 V when the accuracy of data transmission is above 99.5%.

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Parallel Fuzzy Inference Method for Large Volumes of Satellite Images

  • Lee, Sang-Gu
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.1 no.1
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    • pp.119-124
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    • 2001
  • In this pattern recognition on the large volumes of remote sensing satellite images, the inference time is much increased. In the case of the remote sensing data [5] having 4 wavebands, the 778 training patterns are learned. Each land cover pattern is classified by using 159, 900 patterns including the trained patterns. For the fuzzy classification, the 778 fuzzy rules are generated. Each fuzzy rule has 4 fuzzy variables in the condition part. Therefore, high performance parallel fuzzy inference system is needed. In this paper, we propose a novel parallel fuzzy inference system on T3E parallel computer. In this, fuzzy rules are distributed and executed simultaneously. The ONE_To_ALL algorithm is used to broadcast the fuzzy input to the all nodes. The results of the MIN/MAX operations are transferred to the output processor by the ALL_TO_ONE algorithm. By parallel processing of the fuzzy rules, the parallel fuzzy inference algorithm extracts match parallelism and achieves a good speed factor. This system can be used in a large expert system that ha many inference variables in the condition and the consequent part.

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Urban sprawl and its impact on the land cover-a geospatial study

  • Jayakumar, S.;Enkhbaatar, Lkhagva;Heo, Joon
    • Journal of Korean Society for Geospatial Information Science
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    • v.16 no.4
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    • pp.73-78
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    • 2008
  • The present study was aimed to estimate the urban sprawl in a historical city of India using series of satellite data between 1968 and 2005(37 years) and GIS. The total area of the Tiruchirappalli city was 1991.96 ha during 1968 and it was expanded into 4335.98 ha(117.67%) during 2005. The average growth rate per year was 63.35 ha. This 117.67% growth was at the cost of agriculture land(97.81%) and water body(2.19%). The satellite data used in this study were found to be good source of information for this kind of analysis and further studies are need to estimate the impact of this city expansion on agriculture yield and ground water.

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Spectrum Sensing and Data Transmission in a Cognitive Relay Network Considering Spatial False Alarms

  • Tishita, Tasnina A.;Akhter, Sumiya;Islam, Md. Imdadul;Amin, M. Ruhul
    • Journal of Information Processing Systems
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    • v.10 no.3
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    • pp.459-470
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    • 2014
  • In this paper, the average probability of the symbol error rate (SER) and throughput are studied in the presence of joint spectrum sensing and data transmission in a cognitive relay network, which is in the environment of an optimal power allocation strategy. In this investigation, the main component in calculating the secondary throughput is the inclusion of the spatial false alarms, in addition to the conventional false alarms. It has been shown that there exists an optimal secondary power amplification factor at which the probability of SER has a minimum value, whereas the throughput has a maximum value. We performed a Monte-Carlo simulation to validate the analytical results.

Features of Yellow Sand in SeaWiFS Data and Their Implication for Atmospheric Correction

  • Sohn, Byung-Ju;Hwang, Seok-Gyu
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.404-408
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    • 1998
  • Yellow sand event has been studied using SeaWiFS data in order to examine the aerosol optical characteristics in the Yellow Sea and their influences on the atmospheric correction for the ocean color remote sensing. Two SeaWiFS images of April 18 and April 25, 1998, representing Yellow Sand event and clear-sky case respectively, are selected for emphasizing the impact of high aerosol concentration on the ocean color remote sensing. It was shown that NASA's standard atmospheric correction algorithm treats yellow sand area as either too high radiance or cloud area, in which ocean color information is not generated. SeaWiFS aerosol optical thickness is compared with nearby ground-based sun photometer measurements and also is compared with radiative transfer simulation in conjunction with yellow sand model, examining the performance of NASA's atmospheric correction algorithm in case of the heavy dust event.

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An Analysis for Urban Change Using Satellite Images and GIS (GIS와 위성영상을 이용한 도시의 변화량 분석)

  • Shin, Ke-Jong;Yu, Young-Geol;Hwang, Eui-Jin
    • Journal of the Korean GEO-environmental Society
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    • v.6 no.4
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    • pp.73-80
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    • 2005
  • The domestic Remote Sensing field uses mainly Landsat TM image that is used to the monitoring of the wide area. In this study, it is analyzed the land cover change of rural and urban area by time series using satellite images and is proposed the vision for a urban balanced development. It execute an analysis for urban change which is a fundamental data of city planning through the integration of the spatial analysis technique of GIS and Remote Sensing using satellite data.

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Sensor placement strategy for high quality sensing in machine health monitoring

  • Gao, Robert X.;Wang, Changting;Sheng, Shuangwen
    • Smart Structures and Systems
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    • v.1 no.2
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    • pp.121-140
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    • 2005
  • This paper presents a systematic investigation of the effect of sensor location on the data quality and subsequently, on the effectiveness of machine health monitoring. Based on an analysis of the signal propagation process from the defect location to the sensor, numerical simulations using finite element modeling were conducted on a bearing test bed to determine the signal strength at several representative sensor locations. The results showed that placing sensors closely to the machine component being monitored is critical to achieving high signal-to-noise ratio, thus improving the data quality. Using millimeter-sized piezoceramic plates, the obtained results were evaluated experimentally. A comparison with a set of commercial vibration sensors verified the developed structural dynamics-based sensor placement strategy. It further demonstrated that the proposed shock wave-based sensing technique provided an effective alternative to vibration measurement, while requiring less space for sensor installation.

Application of satellite image data to management plan of large-scale irrigation projects

  • Torii, Kiyoshi;Yaota, Kiyoyuki;Hata, Takeshi;Abdelhadi, A.W.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1233-1235
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    • 2003
  • We are studying large-scale irrigation projects of 100,000 ha to 1,000,000 ha in the world with emphasis on their historical courses of development, geographical conditions, water managements, planting conditions and landuse changes. Recent advancement in GIS/remote sensing techniques has enabled us to proceed studies in this field in more details. Here, we describe the results of analysis on distribution of irrigation canals, three-dimensional shape of the irrigation area and planting conditions of agricultural products investigated last year in Gezira irrigation project, Sudan, using Landsat 7 ETM data and DEM supplied by USGS.

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