• Title/Summary/Keyword: Spatial Differences

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Moving Vehicle Detection from Single-pass Worldview-3 Imagery Using Spatial Correlation Map

  • Song, Yongjun;Chung, Minkyung;Kim, Yongil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.40 no.5
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    • pp.439-448
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    • 2022
  • MV (Moving Vehicle) detection using satellite imagery is important for traffic monitoring and provides a wide range of observations. Specifically, MV detection methods utilizing the time lag in single-pass optical satellite images have been studied for detecting MVs from a single set of images. Because of limitations in detecting MVs outside of roads, most previous studies required road information to limit the moving object to cars on the road. However, it is difficult to obtain road information from inaccessible areas. Therefore, this study proposed a new method for detecting MVs regardless of their locations from single-pass optical satellite images without using additional data. WV-3 (Worldview-3) satellite images were used, and a spatial correlation coefficient map was proposed to detect spatial displacement which denotes MVs across two WV-3 MS images. Finally, evaluation was performed through quantitative metrics and visual inspection. The evaluation results revealed that the proposed method can detect MV movements from the single-pass satellite images. On the contrary, misdetected or undetected MVs due to radiometric differences between the images could be identified by visual inspection. The performance of the proposed method can be improved by minimizing radiometric variations and adding conditions that are robust to radiometric differences between the images.

Understanding Geographic Variation in Sales Performance through Offline and Online Channels (지역 특수성에 따른 오프라인·온라인 채널 성과의 이해)

  • Kim, Jeeyeon;Choi, Jeonghye;Chung, Yerim
    • Knowledge Management Research
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    • v.17 no.3
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    • pp.45-64
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    • 2016
  • As the digital retail environement becomes prevalent, consumers are given greater opportunities to make purchases across physical and digital boundaries. Prior research emphasizes that the attractiveness of the digital or online channel is relatively determined by spatial specifics of physical locations. The overall market trend combined with prior research suggests that understanding spatial specifics becomes a key to managing both offline and online sales performance together. In this study, we focus on geographic variation in sales performance through offline and online channels and aim to investigate the channel-level sales difference between central and subsidiary areas. To this end, we obtain sales data of skincare and makeup products from a leading cosmetic company. Next, we examine spatial autocorrelations in data and then employ the spatial error models to study the effects of spatial specifics. The empirical findings are as follows. First, there are significant differences in category-specific and channel-level sales between central and subsidiary areas. Second, Moran's I statistics demonstrate the spatial autocorrelations of each variable. Third, spatial error models outperform simple regression models with lower AIC values. Finally, spatial specifics play a greater role in understanding online sales in subsidiary areas whereas they exert greater influence on offline sales in central areas. We believe our study advances the related theory and knowledge of multi-channel retailing and also contributes practically to location-dependent multi-channel strategies and sales data analytics.

Development of an OpenGIS Spatial Interface based on Oracle (Oracle 기반의 OpenGIS 공간 인터페이스의 개발)

  • Park, Chun-Geol;Park, Hee-Hyun;Kang, Hong-Koo;Han, Ki-Joon
    • Journal of Korea Spatial Information System Society
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    • v.9 no.2
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    • pp.1-11
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    • 2007
  • Recently, with the development of collecting methods of spatial data, the spatial data is produced, circulated, and used in various fields of industry and research. To manage the mass spatial data efficiently, the researches on extension of the existing commercial DBMS, such as ESRI's ArcSDE or Oracle's Oracle Spatial, is making progress actively. However, the usage of the extension of the commercial DBMS Incurs an additional expense and causes an interoperability problem due to differences in spatial data types and spatial operators. Therefore, in this paper, we developed an OpenGIS Spatial Interface for Oracle, which supports a standard interface by fellowing the "Simple Features Specification for SQL" proposed by OGC(Open Geospatial Consortium). Since the OpenGIS Spatial Interface provides all spatial data types and spatial operators proposed in "Simple Features Specification for SQL", users can manage mass spatial data of Oracle efficiently by using the standard interface without additional expense. In addition, we proved that the OpenGIS Spatial Interface is superior to the Oracle Spatial in the response time through the performance evaluation.

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Analysis of Visiting Trade Area by College Students for Clothing Purchase using GIS - Focused on Buying Time - (GIS를 이용한 대학생 의류 구매의 상권 방문 분석 - 구매 시기를 중심으로 -)

  • Jung, Hyun-Ju;Choi, Eun-Mi
    • Journal of the Korean Association of Geographic Information Studies
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    • v.9 no.2
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    • pp.183-193
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    • 2006
  • The purpose of this study is to examine differences in college students' spatial behavior and time for purchasing (weekdays or weekends) according to trading areas they use to purchase casual wears and formal wears. An empirical research developed a questionnaire as a measuring tool to conduct a main survey. McNemar test were carried out by using the SPSS to test statistical differences in spatial buying behaviors between weekdays and weekends. ArcGIS 9.1 and ArcView GIS 3.2a program were applied to visualize the results adopting a spider display technique to understand students clothing buying behaviors. This study obtained the result of that there were differences in college students' selecting a trading area according to the time for purchasing(weekdays or weekends) clothing wears. This study implies that understanding individual clothing spatial behaviors help to set up the strategy of trade area as well as store for marketers related to the fashion industry.

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The Comparative Study on Age-associated Gait Analysis in Normal Korean (우리나라 연령별 보행분석 비교연구)

  • Yoon, Na-Mi;Yoon, Hee-Jong;Park, Jang-Sung;Jeong, Hwa-Su;Kim, Geon
    • The Journal of Korean Physical Therapy
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    • v.22 no.2
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    • pp.15-23
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    • 2010
  • Purpose: This study was done to establish reference data for temporo-spatial, kinematic and kinetic parameters for normal Koreans as they age. Methods: Normal adults and children without a previous history of musculoskeletal problems were enrolled in this study. The normal subjects were divided by age into three groups: Group I: children ($11.95{\pm}0.29$ years); Group II: young adults ($23.90{\pm}3.67$ years); Group III: older adults ($71.40{\pm}4.08$ years). The temporo-spatial and kinematic data were measured using 6 MX3 cameras while each subject walked through a 10 m walkway at a self-selected speed. The kinetic data were measured using 2 force plates and were calculated by inverse dynamics. Results: Motion patterns are typically associated with a specific phase of the gait cycle. Our results were as follows: 1. There were significant differences between the different age groups in temporo-spatial parameters such as cadence, double support, time of foot off, stride length, step length, and walking speed. 2. There were significant differences between the groups in kinematic parameters such as range of motion (ROM) of the hip, knee and ankle in the sagittal plane, ROM of the pelvis, hip and knee in the coronal plane and ROM of the pelvis, hip and ankle in the transverse plane. 3. There were significant differences between the groups in kinetic parameters such as joint moments of force, joint mechanical power generation or absorption and ground reaction forces. Conclusion: The results of this study can be utilized (a) as a reference for kinematic and kinetic data of gait analysis in normal Koreans, and (b) as an aide in evaluating and treating patients who have problems relating to gait.

Differences in the Control of Anticipation Timing Response by Spatio-temporal Constraints

  • Seok-Hwan LEE;Sangbum PARK
    • Journal of Sport and Applied Science
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    • v.7 no.2
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    • pp.39-51
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    • 2023
  • Purpose: The purpose of this study was to investigate differences in the control process to satisfy spatial and temporal constraints imposed upon the anticipation timing response by analyzing the effect of spatio-temporal accuracy demands on eye movements, response accuracy, and the coupling of eye and hand movements. Research design, data, and methodology: 12 right-handed male subjects participated in the experiment and performed anticipation timing responses toward a stimulus moving at three velocities (0.53m/s, 0.66m/s, 0.88m/s) in two task constraint conditions (temporal constraint, spatial constraint). During the response, response accuracy and eye movement patterns were measured from which timing and radial errors, the latency of saccade, fixation duration of the point of gaze (POG), distance between the POG and stimulus, and spatio-temporal coupling of the POG and hand were calculated. Results: The timing and radial errors increased with increasing stimulus velocity, and the spatio-temporal constraints led to larger timing errors than the temporal constraints. The latency of saccade and the temporal coupling of eye and hand decreased with increasing stimulus velocity and were shorter and longer respectively in the spatio-temporal constraint condition than in the temporal constraint condition. The fixation duration of the POG also decreased with increasing stimulus velocity, but no difference was shown between task constraint conditions. The distance between the POG and stimulus increased with increasing stimulus velocity and was longer in the temporal constraint condition compared to the spatio-temporal constraint condition. The spatial coupling of eye and hand was larger with the velocity 0.88m/s than those in other velocity conditions. Conclusions: These results suggest that differences in eye movement patterns and spatio-temporal couplings of stimulus, eye and hand by task constraints are closely related with the accuracy of anticipation timing responses, and the spatial constraints imposed may decrease the temporal accuracy of response by increasing the complexity of perception-action coupling.

A Spatial Analysis of the Causal Factors Influencing China's Air Pollution

  • Kim, Yoomi;Tanaka, Katsuya;Zhang, Xinxin
    • Asian Journal of Atmospheric Environment
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    • v.11 no.3
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    • pp.194-201
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    • 2017
  • This study investigates the factors that affect China's air pollution using city-level panel data and spatial econometric models. We address three air pollutants ($PM_{10}$, $SO_2$, and $NO_2$) present in 30 cities in China between 2004-2012 using global OLS and spatial models. To develop the spatial econometric analysis, we create a spatial weights matrix to define spatial patterns based on two neighborhood criteria - the queen contiguity and k nearest neighbors. The results show that the estimated coefficients are relatively consistent across different spatial weight criteria. The OLS models indicate that the effect of green spaces is statistically significant in decreasing the concentrations of all air pollutants. In the $PM_{10}$ and $SO_2$ analyses, the OLS models find that the number of buses and population density are also positively related to a reduction in the concentration of air pollutants. In addition, an increase in the temperature and the presence of secondary industries increase $SO_2$ and $NO_2$ concentrations, respectively. All spatial models capture a positive and significant effect of green spaces on reducing the concentration of each air pollutant. Our results suggest that green spaces in cities should receive priority consideration in local planning aimed at sustainable development. Furthermore, policymakers need to be able to discern the differences among pollutants when establishing environmental policies.

Assessment of Air Quality Impact Associated with Improving Atmospheric Emission Inventories of Mobile and Biogenic Sources

  • Shin, Tae-joo
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.4 no.1
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    • pp.11-23
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    • 2000
  • Photochemical air quality models are essential tools in predicting future air quality and assessing air pollution control strategies. To evaluate air quality using a photochemical air quality model, emission inventories are important inputs to these models. Since most emission inventories are provided at a county-level, these emission inventories need to be geographically allocated to the computational grid cells of the model prior to running the model. The conventional method for the spatial allocation of these emissions uses "spatial surrogate indicators", such as population for mobile source emissions and county area for biogenic source emissions. In order to examine the applicability of such approximations, more detailed spatial surrogate indicators were developed using Geographic Information System(GIS) tools to improve the spatial allocation of mobile and boigenic source emissions, The proposed spatial surrogate indicators appear to be more appropriate than conventional spatial surrogate indicators in allocating mobile and biogenic source emissions. However, they did not provide a substantial improvement in predicting ground-level ozone(O3) concentrations. As for the carbon monoxide(CO) concentration predictions, certain differences between the conventional and new spatial allocation methods were found, yet a detailed model performance evaluation was prevented due to a lack of sufficient observed data. The use of the developed spatial surrogate indicators led to higher O3 and CO concentration estimates in the biogenic source emission allocation than in the mobile source emission allocation.llocation.

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Effect of the Confusion Level of Dual-Tasks Using a Smartphone on the Gait of Subjects with Chronic Ankle Instability While Walking (보행 중 스마트폰을 이용한 이중과제의 혼란수준이 만성 발목불안정성 성인의 보행에 미치는 영향)

  • Choi, Woo-Sung;Choi, Jong-Duk
    • Journal of the Korean Society of Physical Medicine
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    • v.15 no.3
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    • pp.99-108
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    • 2020
  • PURPOSE: This study examined the effects of the confusion level in performing dual tasks using smartphones while walking in subjects with chronic ankle instability (CAI). METHODS: Twenty subjects with CAI and 20 healthy subjects participated in the study. The spatial, temporal, spatial-temporal, and variability gait parameters were measured using GAITRite under four different conditions: general gait, web surfing during gait, texting during gait, and gaming during gait. Two-way repeated-measures analysis of variance was used to analyze the interaction according to the group (2) and confusion level in dual-tasks (4). One-way repeated-measures analysis of variance was used to compare the changes within the group according to the confusion level in dual-tasks. The changes between groups were compared using an independent t-test. The statistical significance level was set to p = .05. RESULTS: Significant interactions in the temporal and spatial-temporal gait parameters were found between the dual-task conditions and the other groups (p < .05). Significant within-group differences in the spatial, temporal, and spatial-temporal gait parameters were found according to the confusion level in dual tasks (p < .05). Significant between-group differences were observed in the temporal and spatial-temporal gait parameters according to the confusion level in dual tasks (p < .05). CONCLUSION: The effect of the confusion level in dual tasks was greater in subjects with CAI than in healthy individuals. This study suggests that to prevent reinjury to the ankle, subjects with CAI should avoid dual tasks such as using smartphones while walking.

A Study on the Estimation Method of Carbon Storage Using Environmental Spatial Information and InVEST Carbon Model: Focusing on Sejong Special Self-Governing City - Using Ecological and Natural Map, Environmental Conservation Value Assessment Map, and Urban Ecological Map - (환경공간정보와 InVEST Carbon 모형을 활용한 탄소저장량 추정 방법에 관한 연구: 세종시를 중심으로 - 생태·자연도, 국토환경성평가지도, 도시생태현황지도를 대상으로 -)

  • Hwang, Jin-Hoo;Jang, Rae-ik;Jeon, Seong-Woo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.25 no.5
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    • pp.15-27
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    • 2022
  • Climate change is considered a severe global problem closely related to carbon storage. However, recent urbanization and land-use changes reduce carbon stocks in terrestrial ecosystems. Recently, the role of protected areas has been emphasized as a countermeasure to the climate change, and protected areas allow the area to continue to serve as a carbon sink due to legal restrictions. This study attempted to expand the scope of these protected areas to an evaluation-based environmental spatial information theme map. In this study, the area of each grade was compared, and the distribution of land cover for each grade was analyzed using the Ecological and Nature Map, Environmental Conservation Value Assessment Map and Urban Ecological Map of Sejong Special Self-Governing City. Based on this, the average carbon storage for each grade was derived using the InVEST Carbon model. As a result of the analysis, the high-grade area of the environmental spatial information generally showed a wide area of the natural area represented by the forest area, and accordingly, the carbon storage amount was evaluated to be high. However, there are differences in the purpose of production, evaluation items, and evaluation methods between each environmental spatial information, there are differences in area, land cover, and carbon storage. Through this study, environmental spatial information based on the evaluation map can be used for land use management in the carbon aspect, and it is expected that a management plan for each grade suitable for the characteristics of each environmental spatial information is required.