• Title/Summary/Keyword: SPATIAL SCALE

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Multiscale Spatial Position Coding under Locality Constraint for Action Recognition

  • Yang, Jiang-feng;Ma, Zheng;Xie, Mei
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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    • pp.1851-1863
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    • 2015
  • – In the paper, to handle the problem of traditional bag-of-features model ignoring the spatial relationship of local features in human action recognition, we proposed a Multiscale Spatial Position Coding under Locality Constraint method. Specifically, to describe this spatial relationship, we proposed a mixed feature combining motion feature and multi-spatial-scale configuration. To utilize temporal information between features, sub spatial-temporal-volumes are built. Next, the pooled features of sub-STVs are obtained via max-pooling method. In classification stage, the Locality-Constrained Group Sparse Representation is adopted to utilize the intrinsic group information of the sub-STV features. The experimental results on the KTH, Weizmann, and UCF sports datasets show that our action recognition system outperforms the classical local ST feature-based recognition systems published recently.

Development of radar-based quantitative precipitation forecasting using spatial-scale decomposition method for urban flood management (도시홍수예보를 위한 공간규모분할기법을 이용한 레이더 강우예측 기법 개발)

  • Yoon, Seongsim
    • Journal of Korea Water Resources Association
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    • v.50 no.5
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    • pp.335-346
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    • 2017
  • This study generated the radar-based forecasted rainfall using spatial-scale decomposition method (SCDM) and evaluated the hydrological applicability with forecasted rainfall by KMA (MAPLE, KONOS) in terms of urban flood forecasting. SCDM is to separate the small-scale field (convective cell) and large-scale field (straitform cell) from radar rainfield. And each separated field is forecasted by translation model and storm tracker nowcasting model for improvement of QPF accuracy. As the evaluated results of various QPF for three rainfall events in Seoul and Metropolitan area, proposed method showed better prediction accuracy than MAPLE and KONOS considering the simplicity of the methodology. In addition, this study assessed the urban hydrological applicability for Gangnam basin. As the results, KONOS simulated the peak of water depth more accurately than MAPLE and SCDM, however cannot simulated the timeseries pattern of water depth. In the case of SCDM, the quantitative error was larger than observed water depth, but the simulated pattern was similar to observation. The SCDM will be useful information for flood forecasting if quantitative accuracy is improved through the adjustment technique and blending with NWP.

Numerical Analysis of Wintertime Air Pollution in East Asia Region Using Long-Range Transport Model

  • Jang, Eun-Suk
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.4 no.2
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    • pp.103-110
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    • 2000
  • In order to understand the wintertime intermittent characteristics of the trans-boundary air pollutant transport observed in East Asia, a numerical simulation of the long-range transport of pollutants was applied using an atmospheric transport model(STEM-II). The numerical simulation was carried out for the entire month of January 1997 and specific atmospheric aerosol (including sulfate, nitrate, and other ion compounds0 observation data were compared from four observation sites(Cheju Island, Kanghwa Island, Dazaifu, and Fukue Island). The observation data revealed that concentration peaks were intermittently observed at 3 to 4-day intervals plus the four observation sites exhibited a very similar spatial variation. The horizontal and spatial scale of the heavily polluted air masses was analyzed based on numerical results. The mechanism of the intermittent transport of air pollutants was clearly explained by a comparison of the observed data with the numerical output. It was found that the wind pattern variations associated with the synoptic scale pressure system changes play an extremely important role in the transport of pollutants in this region.

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Structure of Particle Clusters Formed in Gas-Solid flows

  • Tanaka, Toshitsugu;Ito, Akihito;Tsuji, Takuya
    • 한국전산유체공학회:학술대회논문집
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    • 2006.10a
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    • pp.26-27
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    • 2006
  • Characteristics of spatial structure of particle clusters are investigated by using the flow field data obtained from three-dimensional numerical simulations. Eulerian/Lagrangian approach with two-way coupling is applied and individual particle-particle collisions are taken into account by using the hard-sphere model. More than 16 million particles are traced in the maximum case. The results show that the cluster is consisted from the multiple-spatial scale components while the low wave-number, hence the large-scale structure, is dominant. Three-dimensional structure reconstructed from the low-pass filtered data enables us to investigate the essential dynamics of particle clusters in detail.

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An empirical study of the effectiveness of spatial navigation system - Focus on large-scale web sites - (공간 지식을 적용한 항해 시스템에 관한 연구 - 대규모 웹 사이트를 중심으로 -)

  • Suh, Jin-Won;Kim, Jin-Woo
    • Asia pacific journal of information systems
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    • v.11 no.2
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    • pp.79-98
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    • 2001
  • As the average size of web sites gets larger, users tend to experience more severe problems while navigating through the sites. In order to alleviate the navigation-related problems, this paper proposes two new navigation systems based on the spatial metaphor to the navigation in the real world. Prototypes of the two system, Complete Route Navigation(CRN) and Complete Survey Navigation(CSN), were developed and applied to four versions of test bed web sites, which were then used in an experiment to test the effectiveness of the two navigation systems. Results from the experiment indicate that the two systems are indeed effective in aiding users to navigate in a large scale web site, and have more positive impacts when provided together. This paper ends with the limits of the study results and their implications to the development of large-scale web sites.

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Crop Field Extraction Method using NDVI and Texture from Landsat TM Images

  • Shibasaki, Ryosuke;Suzaki, Junichi
    • Proceedings of the KSRS Conference
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    • 1998.09a
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    • pp.159-162
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    • 1998
  • Land cover and land use classification on a huge scale, e.g. national or continental scale, has become more and more important because environmental researches need land cover: And land use data on such scales. We developed a crop field extraction method, which is one of the steps in our land cover classification system for a huge area. Firstly, a crop field model is defined to characterize "crop field" in terms of NDVI value and textual information Textual information is represented by the density of straight lines which are extracted by wavelet transform. Secondly, candidates of NDVI threshold value are determined by "scale-space filtering" method. The most appropriate threshold value among the candidates is determined by evaluating the line density of the area extracted by the threshold value. Finally, the crop field is extracted by applying level slicing to Landsat TM image with the threshold value determined above. The experiment demonstrates that the extracted area by this method coincides very well with the one extracted by visual interpretation.

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Comparison of the Spatial Variability of C- and L-Band Remotely Sensed Soil Moisture (원격측정 토양수분자료, (C-band 측정치 vs. L-band 측정치)의 공간변화도 비교)

  • Kim, Gwangseob;Lim, TaeKyung
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.705-708
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    • 2004
  • The spatial variability of the L- and C- band large scale remotely sensed soil moisture data, obtained during tire Southern Great Plain 1999 (SGP'99), was characterized. The results demonstrate that soil moisture data using L-band show the break in statistical symmetry (multiscaling behavior) with the variation of scale of observation, which is similar to that of the soil property such as sand content. Also, soil moisture data using C-band show single scaling behavior with the variation of scale of observation, which Is similar to that of the vegetation condition.

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Influence of Scaling in Drone-based Remotely Sensed Information on Actual Evapotranspiration Estimation (드론 원격정보 격자크기가 실제증발산량 산정에 미치는 영향)

  • Lee, Khil-Ha
    • Journal of Environmental Science International
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    • v.27 no.2
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    • pp.135-141
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    • 2018
  • The specification of surface vegetation is essential for simulating actual evapotranspiration of water resources. The availability of land cover maps based on remotely collected data makes the specification of surface vegetation easier. The spatial resolution of hydrologic models rarely matches the spatial scales of the vegetation data needed, and remotely collected vegetation data often are upscaled up to conform to the hydrologic model scale. In this study, the effects of the grid scale of of surface vegetation on the results of actual evapotranspiration were examined. The results show that the coarser resolution causes larger error in relative terms and that a more realistic description of area-averaged vegetation nature and characteristics needs to be considered when calculating actual evapotranspiration.

Predicting ground-based damage states from windstorms using remote-sensing imagery

  • Brown, Tanya M.;Liang, Daan;Womble, J. Arn
    • Wind and Structures
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    • v.15 no.5
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    • pp.369-383
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    • 2012
  • Researchers have recently begun using high spatial resolution remote-sensing data, which are automatically captured and georeferenced, to assess damage following natural and man-made disasters, in addition to, or instead of employing the older methods of walking house-to-house for surveys, or photographing individual buildings from an airplane. This research establishes quantitative relationships between the damage states observed at ground-level, and those observed from space using high spatial resolution remote-sensing data, for windstorms, for individual site-built one- or two-family residences (FR12). "Degrees of Damage" (DOD) from the Enhanced Fujita (EF) Scale were determined for ground-based damage states; damage states were also assigned for remote-sensing imagery, using a modified version of Womble's Remote-Sensing (RS) Damage Scale. The preliminary developed model can be used to predict the ground-level damage state using remote-sensing imagery, which could significantly lessen the time and expense required to assess the damage following a windstorm.

Research on Factors Affecting South Korea's OFDI Based on a Spatial Measurement Model

  • Su, Shuai;Zhang, Fan
    • Journal of Korea Trade
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    • v.26 no.1
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    • pp.99-112
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    • 2022
  • Purpose - This paper empirically investigates via a spatial lag model from the perspective of space economy to find the influencing factors of South Korea's OFDI along with 60 countries. Design/methodology - In the study of regional economic phenomena, we must first test the corresponding spatial correlation, and on this basis, complete the construction of the spatial model. For the target research object, after testing the spatial correlation, if there is spatial correlation, a spatial measurement model is needed. This paper uses the global Moran's I index for calculation. Based on the characteristics and research needs of the research object, this paper selects the spatial lag model to verify the existence of the spatial effect and factors affecting OFDI. Findings - Our results show that export scale, infrastructure, technology level, political stability, resource endowment, market size, distance and labor cost have a certain impact on Korea's OFDI, but at present the distance and market size factors are the most important influencing factors for South Korea's OFDI, The technical level and political stability have little effect on South Korea's OFDI, and are not main factors determining South Korea's OFDI. Originality/value - Through spatial measurement verification, it was found that the spatial effect has a significant impact on OFDI, along with more than 60 countries. On this basis, relevant suggestions are put forward, which have strong practical significance for South Korea's OFDI to achieve healthy and sustainable development.