• 제목/요약/키워드: Remote Sensing Imagery

검색결과 822건 처리시간 0.026초

EVALUATION OF SURFACE HEAT FLUXES FOR DIFFERENT LAND COVER IN HEAT ISLAND EFFECT

  • Chang, Tzu-Yin;Liao, Lu-Wei;Liou, Yuei-An
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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    • pp.68-71
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    • 2008
  • Our goal is to obtain a better scientific understanding how to define the nature and role of remotely sensed land surface parameters and energy fluxes in the heat island phenomena, and local and regional weather and climate. By using the MODIS visible and thermal imagery data and analyzing the surface energy flux images associated with the change of the landcover and landuse in study area, we will estimate and present how significant is the magnitude of the heat island heat effect and its relation with the surface parameters and the energy fluxes in Taiwan. To achieve our objective, we used the energy budget components such as net radiation, soil heat flux, sensible heat flux, and latent heat flux in the study area of interest derived form remotely sensed data to understand the island heat effect. The result shows that the water is the most important component to decrease the temperature, and the more the consumed net radiation to latent heat, the lower urban surface temperature.

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무인비행기 (UAV) 영상을 이용한 농작물 분류 (Crops Classification Using Imagery of Unmanned Aerial Vehicle (UAV))

  • 박진기;박종화
    • 한국농공학회논문집
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    • 제57권6호
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    • pp.91-97
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    • 2015
  • The Unmanned Aerial Vehicles (UAVs) have several advantages over conventional RS techniques. They can acquire high-resolution images quickly and repeatedly. And with a comparatively lower flight altitude i.e. 80~400 m, they can obtain good quality images even in cloudy weather. Therefore, they are ideal for acquiring spatial data in cases of small agricultural field with mixed crop, abundant in South Korea. This paper discuss the use of low cost UAV based remote sensing for classifying crops. The study area, Gochang is produced by several crops such as red pepper, radish, Chinese cabbage, rubus coreanus, welsh onion, bean in South Korea. This study acquired images using fixed wing UAV on September 23, 2014. An object-based technique is used for classification of crops. The results showed that scale 250, shape 0.1, color 0.9, compactness 0.5 and smoothness 0.5 were the optimum parameter values in image segmentation. As a result, the kappa coefficient was 0.82 and the overall accuracy of classification was 85.0 %. The result of the present study validate our attempts for crop classification using high resolution UAV image as well as established the possibility of using such remote sensing techniques widely to resolve the difficulty of remote sensing data acquisition in agricultural sector.

일본의 원격탐사 활용 실태 및 정책 동향 (Status of Remote Sensing and Data Policy in Japan)

  • 윤보열;장희욱;김윤수
    • 항공우주산업기술동향
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    • 제9권1호
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    • pp.45-54
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    • 2011
  • 최근 전 세계 다양한 지구관측 위성이 개발 및 발사됨에 따라 다양한 분야로 위성영상 자료의 활용이 확대되고 그에 따른 지구관측 위성영상 시장의 규모가 점점 커지고 있는 추세이다. 일본의 경우 빈번하게 발생하는 재해재난 분야에 대응하고, 실질적으로 피해복구 지원에 ALOS 위성자료를 적극적으로 활용하고 있으며, 전 세계 재해재난 저감 활동에 자국이 보유한 위성자료를 지원하여 국제사회에 기여하는 바가 크다고 할 수 있다. 본 논문을 통하여 일본의 원격탐사 활용 실태와 관련 정책 동향을 살펴보고자 한다. 또한, 위성기반의 원격탐사 기술이 국민 실생활에 어떻게 효율적으로 기여할 수 있을 지에 대한 방안과 관련 지원을 위해 요구되는기반시스템의구축에대해서조사하였다.

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Footprint extraction of urban buildings with LIDAR data

  • Kanniah, Kasturi Devi;Gunaratnam, Kasturi;Mohd, Mohd Ibrahim Seeni
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.113-119
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    • 2003
  • Building information is extremely important for many applications within the urban environment. Sufficient techniques and user-friendly tools for information extraction from remotely sensed imagery are urgently needed. This paper presents an automatic and manual approach for extracting footprints of buildings in urban areas from airborne Light Detection and Ranging (LIDAR) data. First a digital surface model (DSM) was generated from the LIDAR point data. Then, objects higher than the ground surface are extracted using the generated DSM. Based on general knowledge on the study area and field visits, buildings were separated from other objects. The automatic technique for extracting the building footprints was based on different window sizes and different values of image add backs, while the manual technique was based on image segmentation. A comparison was then made to see how precise the two techniques are in detecting and extracting building footprints. Finally, the results were compared with manually digitized building reference data to conduct an accuracy assessment and the result shows that LIDAR data provide a better shape characterization of each buildings.

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The use of remotely sensed data to estimate the heat island effect in the central part of Taiwan

  • Chang, Tzuyin;Liou, Yuei-An
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.319-321
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    • 2003
  • It is our goal to obtain a better scientific understanding of how to define the nature and role of remotely sensed land surface parameters and energy fluxes in the heat island phenomena, and local and regional weather and climate. By using the TRMM (Tropical Rainfall Measuring Mission) visible and thermal imagery data and analyzing the surface energy flux images associated with the change of the landcover and land use in the study area, we present how significant is the magnitude of the heat island heat effect and its relation with the surface parameters and the energy fluxes in the Taichung area of Taiwan. We used the energy budget components such as net radiation, soil heat flux, sensible heat flux, and latent heat flux in the study area of interest derived form remotely sensed data to understand the island heat effect in Taichung. The results show that water is the most important component to decrease the temperature, and the more the consumed net radiation to latent heat, the lower the urban surface temperature.

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Evolution of Internal Waves Near a Turning Point in the South China Sea using SAR Imagery and Numerical Models

  • Kim, Duk-Jin;Lyzenga, David R.;Choi, Woo-Young;Kim, Youn-Soo
    • 대한원격탐사학회지
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    • 제23권5호
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    • pp.385-391
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    • 2007
  • Subsurface Internal Waves(IWs) can be detected in satellite images as periodic alternating brighter/darker stripes. It is known that there are two types of IWs-depression type and elevation type-depending on the water depth in stratified oceans. In this study, we have quantitatively verified the process of converting polarity from depression waves to elevation waves using ERS-2 SAR image acquired over the northern South China Sea. We simulated the evolution of IWs near a turning point with a numerical model for internal wave propagation. The simulation results near the turning point clearly showed us not only a conversion process of IWs from depression to elevation waves, but also a similar wave pattern with the observed SAR image. We also simulated SAR intensity variation near the turning point. The upper layer currents were computed at regular intervals using the numerical model, as the IWs were passing through the turning point. Then, an integrated hydrodynamic-electromagnetic model was used for simulating SAR intensity profiles from the upper layer currents. The simulated SAR intensity profiles were compared with the observed SAR intensities.

Generation of Super-Resolution Benchmark Dataset for Compact Advanced Satellite 500 Imagery and Proof of Concept Results

  • Yonghyun Kim;Jisang Park;Daesub Yoon
    • 대한원격탐사학회지
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    • 제39권4호
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    • pp.459-466
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    • 2023
  • In the last decade, artificial intelligence's dramatic advancement with the development of various deep learning techniques has significantly contributed to remote sensing fields and satellite image applications. Among many prominent areas, super-resolution research has seen substantial growth with the release of several benchmark datasets and the rise of generative adversarial network-based studies. However, most previously published remote sensing benchmark datasets represent spatial resolution within approximately 10 meters, imposing limitations when directly applying for super-resolution of small objects with cm unit spatial resolution. Furthermore, if the dataset lacks a global spatial distribution and is specialized in particular land covers, the consequent lack of feature diversity can directly impact the quantitative performance and prevent the formation of robust foundation models. To overcome these issues, this paper proposes a method to generate benchmark datasets by simulating the modulation transfer functions of the sensor. The proposed approach leverages the simulation method with a solid theoretical foundation, notably recognized in image fusion. Additionally, the generated benchmark dataset is applied to state-of-the-art super-resolution base models for quantitative and visual analysis and discusses the shortcomings of the existing datasets. Through these efforts, we anticipate that the proposed benchmark dataset will facilitate various super-resolution research shortly in Korea.

Application of OGC services to Digital Asia

  • Hiraishi, Kenji;Shibata, Norifumi;Nagano, Tetsuya
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1436-1438
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    • 2003
  • A prototype of OGC Web Map Service and Web Feature Service is developed by NEC Aerospace Systems, Ltd. under the contract from NASDA and RESTEC. The server provides satellite imagery data taken by JERS-1 and ADEOS satellite, via OGC interfaces to the client. The related features are also available to the client through the Internet with OGC interfaces. The imagery, map and feature data is handled layer by layer at the client. OGC Web Map Service and Web Feature Service interoperability capability and applicability to Digital Asia Network are demonstrated.

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Development Technique for Dynamic Node Management of Visual Modeler

  • Yoon, C.R.;Kim, K.O.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1131-1133
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    • 2003
  • Spatial image processing software requires various user interactions to make a plan, prepare necessary data such as images, vectors, ancillary data and user-defined data, execute functions according to pre-defined procedures, analyze and store the results. In this manner, overall processes are controlled by user interactions. In this paper, we propose visual modeler which has the automated spatial image processing technique to minimize user interactions and re -use repeatable procedure. The proposed visual modeler is designed to use inter-operable components proposed by OpenGIS consortium as well as conventional COM components.

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Development of Feature-based Classification Software for High Resolution Satellite Imager

  • Jeong, Soo;Kim, Kyung-Ok;Jeong, Sang-Yong
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.1111-1113
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    • 2003
  • In this paper, we investigated a method for feature - based classification to develop software which is suitable to the classification of high resolution satellite imagery . So, we developed related algorithm and designed user interfaces of convenience, considering various elements require for the feature - based classification. The software was tested with eCognition software which is unique commercial software for feature - based classification.

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