• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.7
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• pp.3018-3040
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• 2018

The mobility model is one of the most important factors that impacts the evaluation of any transportation vehicular networking protocols via simulations. However, to obtain a realistic mobility model in the dynamic urban environment is a very challenging task. Several studies extract mobility models from large-scale real data sets (mostly taxi GPS data) in recent years, but they do not consider the statuses of taxi, which is an important factor affected taxi's mobility. In this paper, we discover three simple observations related to the taxi statuses via mining of real taxi trajectories: (1) the behavior of taxi will be influenced by the statuses, (2) the macroscopic movement is related with different geographic features in corresponding status, and (3) the taxi load/drop events are varied with time period. Based on these three observations, a novel taxi mobility model (T-START) is proposed with respect to taxi statuses, geographic region and time period. The simulation results illustrate that proposed mobility model has a good approximation with reality in trajectory samples and distribution of nodes in four typical time periods.

• Atmosphere
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• v.21 no.1
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• pp.95-108
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• 2011

The effects of an apartment complex on flow and pollutant dispersion in an urban area are numerically investigated using a computational fluid dynamics (CFD) model. The CFD model is based on the Reynolds-averaged Navier-Stokes equations and includes the renormalization group k-${\varepsilon}$ turbulence model. The geographic information system (GIS) data is used as an input data of the CFD model. Eight numerical simulations are carried out for different inflow directions and, for each inflow direction, the effects of an apartment complex are investigated, comparing the characteristics of flow and dispersion before and after construction of the apartment complex in detail. The observation data of automatic weather system (AWS) is analyzed. The windrose analysis shows that the wind speed and direction after the construction of the complex are quite different from those before the construction. The construction of the apartment complex resulted in the decrease in wind speed at the downwind region. It is also shown that the wind speed increased partially inside the apartment complex due to the channeling effect to satisfy the mass continuity. On the whole, the wind speed decreased at the downwind region due to the drag effect by the apartment complex. As a result, the passive pollutant concentration increased (decreased) near the downwind region of (within) the apartment complex compared with that before the construction.

• The Journal of Sustainable Design and Educational Environment Research
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• v.3 no.1
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• pp.35-45
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• 2003

This study purpose is the consideration of the processing evolution historic of the Educational Facilities 20s century at the grand view in the region Ile-de-France. Specially, by thepart of Educational Politic, Urban Geographic and the Urban Planning. This study purpose is to take a data base and study direction on 'A study of the role educational facility in the urban development'. So I was arrived these conclusions, First, the educational politic of the france was aimed for the democratization of the education and the popularization. After execution of the decentralization in the 1986, high school facilities was more popularized. Second, in the view point of the urban geographic, before 1975 years, high school facilities in the region ile-de-france was unbalanced in the situation regional and in the division social on the urban space. But after law of the Decentralization(1986) in the France, by effort of the regional conseil has take the regional balance. Third, high school facility has a potential force as a center of the development of the city. Forth, the facility has a possibility potential for a working of the important role in the urbanization. specially, the movement of population, the augment prix of the terrain, appartement and the division social in the urban space. as element that important relation with a development of the city.

• Asian Journal of Innovation and Policy
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• v.12 no.1
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• pp.101-130
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• 2023

The increasing cost, and demand for, household energy has increased attention to the phenomena of energy burdens. Despite this increased attention, a lack of consensus remains in pinpointing the strongest predictors, and geographic differences, that exist within the energy ecosystem. This study addresses this gap by utilizing a series of dummy variable regressions across cities, suburbs, and rural areas within Erie County, New York-a county noted to have particularly high energy burdens. Specifically, three types of predictor sets were incorporated into the methodology: a set of socioeconomic variables, physical variables, and a combination of both variable sets. The results of this study suggest that cities tend to have the highest electricity burdens. Despite the aging infrastructure in Erie County, high energy burdens were driven primarily by socioeconomic factors such as housing cost burden and poverty status. Lastly, this study explores various planning and policy implications Erie County can utilize to reduce energy burdens. In turn, this study highlights the importance of focusing policy efforts on existing social service programs to provide support to the region's neediest households.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2003.04a
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• pp.297-299
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• 2003

Altimeter(Topex/Poseidon) and AVHRR(NOAA) data were used to study the variations and correlations of Sea Level(SL) and Sea Surface Temperature (SST) in the North East Asian Seas from November 1993 to May 1998. This region is influenced simultaneously to continental and oceanic climate as the border of the East Sea(Japan Sea). SL and SST have increased gradually every year because the global warming, and presented usually a strong annual variations in Kuroshio extension region with the influence of bottom topography.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.493-498
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• 2014

Purpose: This study utilized the Geographic Information System (GIS) which is one of the representative methods for describing visual distribution, to show the distribution of visions of middle and high school students in 16 cities or provinces in Korea. Method: The data of National Health and Nutrition Examination Survey (NHANES) were analysed from 2009 to 2011 and designed a population-based cross-sectional study. The subjects were total 1,049 students at the age of 13 to 18 and uncorrected vision was provided. Male subjects were 549 (52.3%) and female subjects were 500 (47.7%). Subjects were divided into 16 cities or provinces and average vision of regions were analysed. the differentials of vision among the regions were analysed by as a spatial analysis method. Results: The average uncorrected vision were significant difference by sex (p=0.001). However male and female student groups' average vision indicated no statistically significant difference by region in those 16 cities and provinces. In order to show the differentials of middle and high school students' vision by region with a visual distribution method, the GIS was utilized for mapping. Conclusions: The differentials of vision among regions by GIS provide a visually effective distribution map.

• Journal of Environmental Health Sciences
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• v.48 no.6
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• pp.298-305
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• 2022

Background: The concentration of air pollutants as measured by the Air Quality Monitoring System (AQMS) is not an accurate population exposure level since actual human activities and temporal and spatial variability need to be considered. Therefore, to increase the accuracy of exposure assessment, the population should be considered. However, it is difficult to obtain population data due to limitations such as personal information. Objectives: The existing population defined in this study is the number of people in each region's grid. The purpose is to provide a methodology for evaluating exposure to PM_2.5 through existing population data provided by the National Geographic Information Institute. Methods: The selected study period was from October 26 to October 28, 2021. Using PM_2.5 concentration data measured at the Sensor-based Air Monitoring Station (SAMS) installed in Guro-gu and Wonju-si, the concentration for each grid was estimated by applying inverse distance weights through QGIS version 3.22. Considering the existing population, population-weighted average concentration (PWAC) was calculated and the exposure level of the population was compared by region. Results: The outdoor PM_2.5 concentration as measured through the SAMS was high in Wonju-si on all three days. Wonju-si showed an average 22% higher PWAC than Guro-gu. As a result of comparing the PWAC and outdoor PM_2.5 concentration by region, the PWAC in Guro-gu was 1~2% higher than the observed value, but it was almost the same. Conversely, observations of Wonju-si were 10.1%, 11.3%, and 8.2% higher than PWAC. Conclusions: It is expected that the Geographic Information System (GIS) method and the existing population will be used to evaluate the exposure level of a population with a narrow activity radius in further research. In addition, based on this study, it is judged that research on exposure to environmental pollutants and risk assessment methods should be expanded.

• Journal of Forest and Environmental Science
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• v.30 no.1
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• pp.91-100
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• 2014

This research was conducted on the conservation area of Baekdudaegan, Kangwondo under the purpose of evaluating bio-diversity according to the changes of spatial scale, using GIS data and spatial filtering method. The diversity index was calculated based on the information of species of The $5^{th}$ forest type map using Shannon-weaver index (H'), evenness index ($E_i$) and richness index ($R_i$). The diversity index was analyzed and compared according to the changes of 12 spatial scales from Kernel size $3{\times}3$ to $73{\times}73$ and basin unit. As for H' and $R_i$, spatial scale increased as diversity index decreased, while $E_i$ decreases gradually. H' and $R_i$ was highest; each 1.1 and 0.6, when the Kernel size was $73{\times}73$, while $E_i$ was 0.2, the lowest. When you look at according to the basin unit, for large basin unit, 'YeongDong' region shows higher diversity index than 'YeongSeo' region. For middle basin unit, 'Gangneung Namdaecheon' region, and for small basin unit, 'Gangneung Namdaecheon' and 'Gangneung Ohbongdaem' region shows high diversity index. When you look at the relationship between diversity index and Geographic factors, H' shows positive relation to curvature and sunshine factor while shows negative to elevation, slope, hillshade, and wetness index. Also $E_i$ was similar to the relationship between H' and Geographic factor. Meanwhile, $R_i$ shows positive relationship to curvature and sunshine factor, while negative to elevation, slope, hillshade, and wetness index. macro unit diversity index evaluation was possible through the GIS data and spatial filtering, and it can be a good source for local biosphere conservation policy making.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.4
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• pp.65-76
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• 2017

The purpose of this study was to present a prediction model that reflects crime risk area analysis, including factors and spatial characteristics, as a precursor to preparing an alternative plan for crime prevention and design. This analysis of criminal cases in high-risk areas revealed clusters in which approximately 25% of the cases within the study area occurred, distributed evenly throughout the region. This means that using a multiple linear regression model might overestimate the crime rate in some regions and underestimate in others. It also suggests that the number of deserted houses in an analyzed region has a negative relationship with the dependent variable, based on the multiple linear regression model results, and can also have different influences depending on the region. These results reveal that closure signs in a study area affect the dependent variable differently, depending on the region, rather than a simple or direct relationship with the dependent variable, as indicated by the results of the multiple linear regression model.

• Animal cells and systems
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• v.2 no.2
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• pp.259-267
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• 1998

A deletion of one out of the two copies of 9-bp repeat sequence (CCCCCTCTA), between the cytochrome oxidase II and Iysine tranfer RNA (COII/$tRNA^{Lys}$) genes in human mitochondrial DNA (mtDNA) has been used as a polymorphic anthropological marker for people of east Asian origin, and to lesser extent, Pacific and African populations. We searched for the 9-bp deletion of the intergenic COII/$tRNA^{Lys}$ Lys region in two Korean populations (175 from Seoul and 38 from Cheju) and examine the distibution of this deletion in world populations. The 9-bp deletion was detected directly by electrophoresis of the polymerase chain reaction (PCR)-amplified nucleotide(nt) 8211-8310 mtDNA fragment. The frequencies of the 9-bp deletion were significantly different between the Seoul (16%) and Cheju (8%) populations. Examination of data from the world populations suggests a geographic gradient. The frequency reaches its highest values in some Pacific island populations and decreases along the southeast Asia-Siberia transect. In spite of this geographic gradient, Mongoloid populations including Korean, Chinese, Japanese, and Mongolian populations were relatively homo-geneous with regard to the 9-bp deletion type of the intergenic COII/$tRNA^{Lys}$ region. These results indicate Koreans are genetically related to northeast Asian populations, and have a maternal mongoloid ancestry. Therefore, the 9-bp deletion of the intergenic COII/$tRNA^{Lys}$ region will provide significant information to elucidate the historical patterns of migration of the Mongoloids.