• Title/Summary/Keyword: Spatial Effect

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Spatial Correlations of Brain fMRI data

  • Choi Kyungmee
    • Communications for Statistical Applications and Methods
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    • v.12 no.1
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    • pp.241-252
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    • 2005
  • In this study we suggest that the spatial correlation structure of the brain fMRI data be used to characterize the functional connectivity of the brain. For some concussion and recovery data, we examine how the correlation structure changes from one step to another in the data analyses, which will allow us to see the effect of each analysis to the spatial correlation or the functional connectivity of the brain. This will lead us to spot the processes which cause significant changes in the spatial correlation structure of the brain. We discuss whether or not we can decompose correlation matrices in terms of its causes of variations in the data.

Constraint Data Modeling for Spatiotemporal Data Application (시공간 데이터 응용을 위한 제약 데이터 모델링)

  • Jung, Hun Jo;Woo, Sung Koo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.6 no.4
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    • pp.45-56
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    • 2010
  • This paper suggests constraint data modeling based on constraint data presentation techniques to perform complex spatial database operation naturally. We were able to identify the limitation of extendibility of dimension and non-equal framework via relevant research for former schema of spatial database and query processing. Therefore we described generalized tuple of spatial data and the definition of suggested constraint data modeling. Also we selected MLPQ/PReSTO tool among constraint database prototype and compare standard functionality of ARC/VIEW. Then we design scenario for spatial operation using MLPQ/PReSTO and we suggested application effect after query processing. Based on above explanation, we were able to identify that we can process spatial data naturally and effectively using simple constraint routine on same framework via constraint data modeling.

Evaluation of spatial pressure distribution during ice-structure interaction using pressure indicating film

  • Kim, Hyunwook;Ulan-Kvitberg, Christopher;Daley, Claude
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.6 no.3
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    • pp.578-597
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    • 2014
  • Understanding of 'spatial' pressure distribution is required to determine design loads on local structures, such as plating and framing. However, obtaining a practical 'spatial' pressure distribution is a hard task due to the sensitivity of the data acquisition frequency and resolution. High-resolution Pessure-Idicating Flm (PIF) was applied to obtain pressure distribution and pressure magnitude using stepped crushing method. Different types of PIF were stacked at each test to creating a pressure distribution plot at specific time steps. Two different concepts of plotting 'spatial' pressure-area curve was introduced and evaluated. Diverse unit pixel size was chosen to investigate the effect of the resolution in data analysis. Activated area was not significantly affected by unit pixel size; however, total force was highly sensitive.

Impacts of temporal dependent errors in radar rainfall estimate for rainfall-runoff simulation

  • Ko, Dasang;Park, Taewoong;Lee, Taesam
    • Proceedings of the Korea Water Resources Association Conference
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    • 2015.05a
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    • pp.180-180
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    • 2015
  • Weather radar has been widely used in measuring precipitation and discharge and predicting flood risks. The radar rainfall estimate has one of the essential problems in terms of uncertainty and accuracy. Previous study analyzed radar errors to reduce its uncertainty or to improve its accuracy. Furthermore, a recent analyzed the effect of radar error on rainfall-runoff using spatial error model (SEM). SEM appropriately reproduced radar error including spatial correlation. Since the SEM does not take the time dependence into account, its time variability was not properly investigated. Therefore, in the current study, we extend the SEM including time dependence as well as spatial dependence, named after Spatial-Temporal Error Model (STEM). Radar rainfall events generated with STEM were tested so that the peak runoff from the response of a basin could be investigated according to dependent error. The Nam River basin, South Korea, was employed to illustrate the effects of STEM on runoff peak flow.

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Using spatial misalignment Method to Measure and Evaluate unbalanced reginal tourism development in Southwest China

  • Lee, Rui;Kim, Hyung-Ho
    • International Journal of Advanced Culture Technology
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    • v.9 no.3
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    • pp.23-33
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    • 2021
  • "China's Western Development Policy" has brought multiple opportunities to the development of tourism in Southwest China including Sichuan, Guizhou, Yunnan, Chongqing and Tibet. The 4 provinces and 1 municipality overall show a certain degree of accumulation effect and coordinated development in tourism due to their location, traffic and traditional economic cooperation. This study takes the Southwest China as the research object and utilized the spatial dislocation model and the tourism spatial misalignment index to estimate the mismatch degree between tourism resources and tourism income among provinces and try to find out the internal reason background. The results show that each of the five provinces has its own advantages in index of economy, tourism resources, human resource, and transportation, leading to differences in the center of gravity of the entire region in all aspects. In view of the results of spatial dislocation analysis, suggestions for improvement and optimization are put forward to promote the high-quality development of tourism in Southwest region. development.

Skin Lesion Segmentation with Codec Structure Based Upper and Lower Layer Feature Fusion Mechanism

  • Yang, Cheng;Lu, GuanMing
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.16 no.1
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    • pp.60-79
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    • 2022
  • The U-Net architecture-based segmentation models attained remarkable performance in numerous medical image segmentation missions like skin lesion segmentation. Nevertheless, the resolution gradually decreases and the loss of spatial information increases with deeper network. The fusion of adjacent layers is not enough to make up for the lost spatial information, thus resulting in errors of segmentation boundary so as to decline the accuracy of segmentation. To tackle the issue, we propose a new deep learning-based segmentation model. In the decoding stage, the feature channels of each decoding unit are concatenated with all the feature channels of the upper coding unit. Which is done in order to ensure the segmentation effect by integrating spatial and semantic information, and promotes the robustness and generalization of our model by combining the atrous spatial pyramid pooling (ASPP) module and channel attention module (CAM). Extensive experiments on ISIC2016 and ISIC2017 common datasets proved that our model implements well and outperforms compared segmentation models for skin lesion segmentation.

The Effects of Variety and Visual Cue on PerceivedQuantity and Consumer Attitude toward Participationinto Sales Promotion Events

  • Lee, Changhyun;Kim, Youngchan
    • Asia Marketing Journal
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    • v.21 no.1
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    • pp.65-87
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    • 2019
  • Most studies on how people perceive a given quantity of items were conducted with visual cues exclusively and only offered spatial area based explanations, such as spatial estimation and perceptual grouping theories. This article establishes how people perceive a given quantity when only a written description is provided without any visual cues. Across two studies we show that variety decreases perceived quantity when a variety cue is given, while variety increases perceived quantity when a visual cue is not given. This is because people tend to rely heavily on spatial areas when a visual cue is present and because people are prone to confirmation bias when they are provided with no visual cues but only written descriptions. Furthermore, we highlight that quantity perception has a mediation effect on consumers' attitude-the intention to participate in sales promotional events. Lastly, we summarize the article and discuss its contributions, implications, limitations, and suggestions for future research.

Effect of Specimen Thickness on the Statistical Properties of Fatigue Crack Growth Resistance in BS4360 Steel

  • Kim, Seon-Jin;Itagaki, Hiroshi;Ishizuka, Tetsuo
    • Journal of Mechanical Science and Technology
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    • v.14 no.10
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    • pp.1041-1050
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    • 2000
  • In this paper the effect of specimen thickness on fatigue crack growth with the spatial distribution of material properties is presented. Basically, the material resistance to fatigue crack growth is treated as a spatial stochastic process, which varies randomly on the crack surface. The theoretical autocorrelation functions of fatigue crack growth resistance with specimen thickness are discussed for several correlation lengths. Constant ${\Delta}K$ fatigue crack growth tests were also performed on CT type specimens with three different thicknesses of BS 4360 steel. Applying the proposed stochastic model and statistical analysis procedure, the experimental data were analyzed for different specimen thicknesses for determining the autocorrelation functions and probability distributions of the fatigue crack growth resistance.

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Spatial analysis of Design storm depth using Geostatistical (지구통계학적 기법을 이용한 설계호우깊이 공간분석)

  • Ahn, Sang Jin;Lee, Hyeong Jong;Yoon, Seok Hwan;Kwark, Hyun Goo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.1047-1051
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    • 2004
  • The design storm is a crucial element in urban drainage design and hydrological modeling. The total rainfall depth of a design storm is usually estimated by hydrological frequency analysis using historic rainfall records. The different geostatistical approaches (ordinary kriging, universal kriging) have been used as estimators and their results are compared and discussed. Variogram parameters, the sill, nugget effect and influence range, are analysis. Kriging method was applied for developing contour maps of design storm depths In bocheong stream basin. Effect to utilize weather radar data and grid-based basin model on the spatial variation characteristics of storm requires further study.

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A Study on the Application of Visual Depth In Aspects of the Spatial Organization of Architecture (건축공간(建築空間) 구성(構成)에 있어서 시각적(視覺的) 깊이의 활용(活用)에 관(關)한 연구(硏究))

  • Baek, Min-Seok
    • Journal of The Korean Digital Architecture Interior Association
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    • v.3 no.1
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    • pp.1-8
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    • 2003
  • Perceiving the depth of space in the spatial organization of architecture is perceiving spaces as well three dimensions as the fourth dimensions -perceive the time-. Physical depth in architectural space differs from perceptional depth in aspects of not only dimension but also perceptional effects. In this study, the perceptional depth is defined as visual depth and physical depth is depth of space. These purposes of this study are classifying the perceptional effects of visual depth -visual access, sense of variety, dynamic and cubic effect... - and the methods of spatial composition which causes visual depth in architectural space.

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