• Title/Summary/Keyword: Actual Resolution

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A Study on the Improvement of Accuracy in Mapping the Distribution of the Emission Volume of Air Pollution Using GIS (GIS를 이용한 대기오염 배출량 분포도의 정확도 향상에 관한 연구)

  • 최진무
    • Spatial Information Research
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    • v.6 no.1
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    • pp.65-76
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    • 1998
  • Air contaminant density must be inferred exactly to manage air pollution. Each land use of air pollution source is duplicated in the existing air contaminant distribution because the resolution of the land use map is low. The purpose of this study is to understand how the land use map is used to determine effectively in the distribution calculation of the emission volume and the inference of air contaminant density, as it is made in a high resolution. The major findings are as follows : In this study, as to making a high resolution($28.5m{\times}28.5m$) map of land use with GIS, each air pollution source is not duplicated spatially and land use can be reflected effectively. In Seoul, each air contaminant density was inferred (using a TCM-2 model) with the existing distribution map of emission volume, whose resolution is $1km{\times}1km$, and the new distribution map of emission volume, whose resolution is $28.5km{\times}28.5km$. According to the result, the inference value of the new distribution map was more similar to the actual value of an automatic survey network.

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Performance of Support Vector Machine for Classifying Land Cover in Optical Satellite Images: A Case Study in Delaware River Port Area

  • Ramayanti, Suci;Kim, Bong Chan;Park, Sungjae;Lee, Chang-Wook
    • Korean Journal of Remote Sensing
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    • v.38 no.6_4
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    • pp.1911-1923
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    • 2022
  • The availability of high-resolution satellite images provides precise information without direct observation of the research target. Korea Multi-Purpose Satellite (KOMPSAT), also known as the Arirang satellite, has been developed and utilized for earth observation. The machine learning model was continuously proven as a good classifier in classifying remotely sensed images. This study aimed to compare the performance of the support vector machine (SVM) model in classifying the land cover of the Delaware River port area on high and medium-resolution images. Three optical images, which are KOMPSAT-2, KOMPSAT-3A, and Sentinel-2B, were classified into six land cover classes, including water, road, vegetation, building, vacant, and shadow. The KOMPSAT images are provided by Korea Aerospace Research Institute (KARI), and the Sentinel-2B image was provided by the European Space Agency (ESA). The training samples were manually digitized for each land cover class and considered the reference image. The predicted images were compared to the actual data to obtain the accuracy assessment using a confusion matrix analysis. In addition, the time-consuming training and classifying were recorded to evaluate the model performance. The results showed that the KOMPSAT-3A image has the highest overall accuracy and followed by KOMPSAT-2 and Sentinel-2B results. On the contrary, the model took a long time to classify the higher-resolution image compared to the lower resolution. For that reason, we can conclude that the SVM model performed better in the higher resolution image with the consequence of the longer time-consuming training and classifying data. Thus, this finding might provide consideration for related researchers when selecting satellite imagery for effective and accurate image classification.

Multiscale features and information extraction of online strain for long-span bridges

  • Wu, Baijian;Li, Zhaoxia;Chan, Tommy H.T.;Wang, Ying
    • Smart Structures and Systems
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    • v.14 no.4
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    • pp.679-697
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    • 2014
  • The strain data acquired from structural health monitoring (SHM) systems play an important role in the state monitoring and damage identification of bridges. Due to the environmental complexity of civil structures, a better understanding of the actual strain data will help filling the gap between theoretical/laboratorial results and practical application. In the study, the multi-scale features of strain response are first revealed after abundant investigations on the actual data from two typical long-span bridges. Results show that, strain types at the three typical temporal scales of $10^5$, $10^2$ and $10^0$ sec are caused by temperature change, trains and heavy trucks, and have their respective cut-off frequency in the order of $10^{-2}$, $10^{-1}$ and $10^0$ Hz. Multi-resolution analysis and wavelet shrinkage are applied for separating and extracting these strain types. During the above process, two methods for determining thresholds are introduced. The excellent ability of wavelet transform on simultaneously time-frequency analysis leads to an effective information extraction. After extraction, the strain data will be compressed at an attractive ratio. This research may contribute to a further understanding of actual strain data of long-span bridges; also, the proposed extracting methodology is applicable on actual SHM systems.

Quantitative Evaluation of Super-resolution Drone Images Generated Using Deep Learning (딥러닝을 이용하여 생성한 초해상화 드론 영상의 정량적 평가)

  • Seo, Hong-Deok;So, Hyeong-Yoon;Kim, Eui-Myoung
    • Journal of Cadastre & Land InformatiX
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    • v.53 no.2
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    • pp.5-18
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    • 2023
  • As the development of drones and sensors accelerates, new services and values are created by fusing data acquired from various sensors mounted on drone. However, the construction of spatial information through data fusion is mainly constructed depending on the image, and the quality of data is determined according to the specification and performance of the hardware. In addition, it is difficult to utilize it in the actual field because expensive equipment is required to construct spatial information of high-quality. In this study, super-resolution was performed by applying deep learning to low-resolution images acquired through RGB and THM cameras mounted on a drone, and quantitative evaluation and feature point extraction were performed on the generated high-resolution images. As a result of the experiment, the high-resolution image generated by super-resolution was maintained the characteristics of the original image, and as the resolution was improved, more features could be extracted compared to the original image. Therefore, when generating a high-resolution image by applying a low-resolution image to an super-resolution deep learning model, it is judged to be a new method to construct spatial information of high-quality without being restricted by hardware.

APPLICATION OF HIGH RESOLUTION SATELLITE IMAGERY ON X3D-BASED SEMANTIC WEB USING SMART GRAPHICS

  • Kim, Hak-Hoon;Lee, Kiwon
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.586-589
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    • 2006
  • High resolution satellite imagery is regarded as one of the important data sets to engineering application, as well as conventional scientific application. However, despite this general view, there are a few target applications using this information. In this study, the possibility for the future wide uses in associated with smart graphics of this information is investigated. The concept of smart graphics can be termed intelligent graphics with XML-based structure and knowledge related to semantic web, which is a useful component for the data dissemination framework model in a multi-layered web-based application. In the first step in this study, high resolution imagery is transformed to GML (Geographic Markup Language)-based structure with attribute schema and geo-references. In the second, this information is linked with GIS data sets, and this fused data set is represented in the X3D (eXtensible 3D), ISO-based web 3D graphic standard, with styling attributes, in the next stop. The main advantages of this approach using GML and X3D are the flourished representations of a source data according to user/clients’ needs and structured 3D visualization linked with other XML-based application. As for the demonstration of this scheme, 3D urban modelling case with actual data sets is presented.

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A Satellite View of Urban Heat Island: Causative Factors and Scenario Analysis

  • Wong, Man Sing;Nichol, Janet;Lee, Kwon-Ho
    • Korean Journal of Remote Sensing
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    • v.26 no.6
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    • pp.617-627
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    • 2010
  • Although many researches for heat island study have been developed, there is little attempt to link the findings to actual and hypothetical scenarios of urban developments which would help to mitigate the Urban Heat Island (UHI) in cities. The aim of this paper is to analyze the UHI at urban area with different geometries, land use, and environmental factors, and emphasis on the influence of different geometric and environmental parameters on ambient air temperature. In order to evaluate these effects, the parameters of (i) Air pollution (i.e. Aerosol Optical Thickness (AOT)), (ii) Green space Normalized Difference Vegetation Index (NDVI), (iii) Anthropogenic heat (AH) (iv) Building density (BD), (v) Building height (BH), and (vi) Air temperature (Ta) were mapped. The optimum operational scales between Heat Island Intensity (HII) and above parameters were evaluated by testing the strength of the correlations for every resolution. The best compromised scale for all parameters is 275m resolution. Thus, the measurements of these parameters contributing to heat island formation over the study areas of Hong Kong were established from mathematical relationships between them and in combination at 275m resolution. The mathematical models were then tabulated to show the impact of different percentages of parameters on HII. These tables are useful to predict the probable climatic implications of future planning decisions.

Knowledge Model for Disaster Dataset Navigation

  • Hwang, Yun-Young;Yuk, Jin-Hee;Shin, Sumi
    • Journal of Information Science Theory and Practice
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    • v.9 no.4
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    • pp.35-49
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    • 2021
  • In a situation where there are multiple diverse datasets, it is essential to have an efficient method to provide users with the datasets they require. To address this suggestion, necessary datasets should be selected on the basis of the relationships between the datasets. In particular, in order to discover the necessary datasets for disaster resolution, we need to consider the disaster resolution stage. In this paper, in order to provide the necessary datasets for each stage of disaster resolution, we constructed a disaster type and disaster management process ontology and designed a method to determine the necessary datasets for each disaster type and disaster management process step. In addition, we introduce a method to determine relationships between datasets necessary for disaster response. We propose a method for discovering datasets based on minimal relationships such as "isA," "sameAs," and "subclassOf." To discover suitable datasets, we designed a knowledge exploration model and collected 651 disaster-related datasets for improving our method. These datasets were categorized by disaster type from the perspective of disaster management. Categorizing actual datasets into disaster types and disaster management types allows a single dataset to be classified as multiple types in both categories. We built a knowledge exploration model on the basis of disaster examples to ensure the configuration of our model.

A study of Satellite Image-Based Stereoscopic Vision System (위성영상 관련 입체도시시스템 개발에 관한 연구)

  • 김감래;김훈정;김주용
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2004.04a
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    • pp.239-243
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    • 2004
  • It does not exist almost that Most satellite image has both high spectral and spatial resolution. In order to apply the satellite image for to be actual, we need numerical and analytical technique development to improve the resolution. Specially in the function of solid illustration, we represent the solid image through the image generation to solid screen. The main function includes magnification, reduction, screen center movement, Panning, territory magnification. The method to process the image includes histogram and contrast modulation. Afterwards, we will develop the function includes 3-dimension cursor to control the elevation position and calculate the ground coordination automatically. There is the layer control includes the representation and the edition of 3D vector, extraction the Z value by On the Ground and digital elevation.

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The Proposal of Reforming for Resolving Medical Malpractice Disputes (의료분쟁 해결제도의 개혁-미국 및 일본의 경험을 중심으로-)

  • 이규식
    • Health Policy and Management
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    • v.1 no.1
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    • pp.72-94
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    • 1991
  • The number of disputes between physicians and patients caused by medical malpractice are showing a sharp increasing over the past several years. The disputes on medical malpractice may be resolved either in court or by direct negotiation between both sides concerned. There are no special acts relating to the civil or penal liability of the physicians in Korea. The medical disputes are decided merely through legal technicalities and without reference to actual medical practice. The current system which does not compensate injured patients adequately or equitably leads to taking a long time consuming for dispute resolution processes. The things make worsed, the problem is due to not being of insurance system or a proper funds for compensation. This research proposes a outline of new and comprehensive alternative for these problems and failure of conventional resolution of medical disputes. So far, we have learned lessons from the excperiencies of resolving medical malpractice disputes of Japan and the United States. The proposal first calls for an administrative arbitration and pretrial screening panels as a condition precedent to trial. The proposal also includes to facilitate with the funds for compensating the injured.

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Adaptive Nonlinear Artificial Dissipation Model for Computational Aeroacoustics (전산공력음향학을 위한 적응형 비선형 인공감쇄모형)

  • Kim Jae Wook;Lee Duck Joo
    • 한국전산유체공학회:학술대회논문집
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    • 2001.10a
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    • pp.11-19
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    • 2001
  • An adaptive nonlinear artificial dissipation model is presented for performing aeroacoustic computations by the high-order and high-resolution numerical schemes based on the central finite differences. An effective formalism of it is devised by combining a selective background smoothing term and a well-established nonlinear shock-capturing term which is for the temporal accuracy as well as the numerical stability. A conservative form of the selective background smoothing term is presented to keep accurate phase speeds of the propagating nonlinear waves. The nonlinear shock-capturing term that has been modeled by the second-order derivative term is combined with it to improve the resolution of discontinuities and stabilize the strong nonlinear waves. It is shown that the improved artificial dissipation model with an adaptive control constant which is independent of problem types reproduces the correct profiles and speeds of nonlinear waves, suppresses numerical oscillations near discontinuity and avoids unnecessary damping on the smooth linear acoustic waves. The feasibility and performance of the adaptive nonlinear artificial dissipation model are investigated by the applications to actual computational aeroacoustics problems.

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