• Journal of Preventive Medicine and Public Health
• /
• v.49 no.4
• /
• pp.230-239
• /
• 2016

Objectives: We aimed to evaluate the effect of geographic units of analysis on measuring geographic variation in medical services utilization. For this purpose, we compared geographic variations in the rates of eight major procedures in administrative units (districts) and new areal units organized based on the actual health care use of the population in Korea. Methods: To compare geographic variation in geographic units of analysis, we calculated the age-sex standardized rates of eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee-replacement surgery, caesarean section, hysterectomy, computed tomography scan, and magnetic resonance imaging scan) from the National Health Insurance database in Korea for the 2013 period. Using the coefficient of variation, the extremal quotient, and the systematic component of variation, we measured geographic variation for these eight procedures in districts and new areal units. Results: Compared with districts, new areal units showed a reduction in geographic variation. Extremal quotients and inter-decile ratios for the eight procedures were lower in new areal units. While the coefficient of variation was lower for most procedures in new areal units, the pattern of change of the systematic component of variation between districts and new areal units differed among procedures. Conclusions: Geographic variation in medical service utilization could vary according to the geographic unit of analysis. To determine how geographic characteristics such as population size and number of geographic units affect geographic variation, further studies are needed.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.31 no.6_1
• /
• pp.483-491
• /
• 2013

By a development of car navigation systems and mobile or positioning technology, it increases interest in location based services, especially pedestrian navigation systems. Updating of digital maps is important because digital maps are mass data and required to short updating cycle. In this paper, we proposed change detection for different network data-sets based on areal feature matching. Prior to change detection, we defined type of updating between different network data-sets. Next, we transformed road lines into areal features(block) that are surrounded by them and calculated a shape similarity between blocks in different data-sets. Blocks that a shape similarity is more than 0.6 are selected candidate block pairs. Secondly, we detected changed-block pairs by bipartite graph clustering or properties of a concave polygon according to types of updating, and calculated Fr$\acute{e}$chet distance between segments within the block or forming it. At this time, road segments of KAIS map that Fr$\acute{e}$chet distance is more than 50 are extracted as updating road features. As a result of accuracy evaluation, a value of detection rate appears high at 0.965. We could thus identify that a proposed method is able to apply to change detection between different network data-sets.

• Korean Journal of Remote Sensing
• /
• v.11 no.1
• /
• pp.65-80
• /
• 1995

Remote Sensing data with ancillary ground-based meteorological data provides the capalility of computing threeof the four surface energy balance components(i.e. net radiation, soil heat flux and sensible heat flux) at different spatial and temporal scales. As a result, this enablis the estimation of the remaining term, latent heat flux. One of the practical applications with this approach is to produce evapotranspiration maps over large areas. This results could estimate and reproduce areal evapotranspiration over large area as much as several hundred sequare kilometers. Moreover, some calculating simulations for the effects of the land use change on the surface heat flux has been made by this method, which is able to estimate evapotranspiration under arbitracy presumed condition. From the simulation of land use change, the results suggests that the land use change in study area can be produce the significant changes in surface heat flux. This preliminary research suggests that the future research should involve development of methods to account for the variability of meteorological parameters brought about by changes in surface conditions and improvements in the modeling of sensible heat transfer across the surface atmosphere interface for partical canopy conditions using remote sensing information.

• Journal of Korean Society for Quality Management
• /
• v.48 no.2
• /
• pp.241-256
• /
• 2020

Purpose: Certain places in Seoul such as Shinchon, Hongdae, and Gangnam, often suffer from sudden overflow of mobile population which can cause serious safety problems. This study suggests the application of spatial CUSUM control chart in monitoring areal population mobility data which is recently provided by Seoul metropolitan government. Methods: Monitoring series of standardized local Moran's I enables one to detect spatio-temporal out-of-control status based on the accumulation of past patterns. Moreover, we visualize such pattern map for more intuitive comprehension of the phenomenon. As a case study, we have analyzed the female mobility population aged 25 to 29 appeared in 51 Jipgyegu near Hongik university on fridays from January, 2017 to June, 2018. They are validated by exploring related articles and through local due diligence. Results: The results of the analysis provide insights in figuring out if the change of the mobility population is short-term by particular incident or long-term by spatial alteration, which allows strategic approach in constructing response system. Specific case near popular downtown near Hongik University has shown that newly opened hotels, shops of global sports brand and franchise bookstores have attracted young female population. Conclusion: We expect that the results of our study contribute to planning effective distribution of administrative resources to prepare against drastic increase in floating population. Furthermore, it can be useful in commercial area analysis and age/gender specific marketing strategy for companies.

• KCID journal
• /
• v.10 no.1
• /
• pp.73-79
• /
• 2003

The purpose of this study is to suggest a simple estimation method of tidal flat areas using multi-temporal Landsat TM images due to the progress of sea dike construction for tidal land reclamation. As a case study, Hwa-ong project in which dike construct

• Journal of Korean Society for Atmospheric Environment
• /
• v.28 no.6
• /
• pp.644-655
• /
• 2012

As soon as a new air filter is applied to an air purification process, the filter gets loaded with dust particles. Thus, the study on the particle loading characteristics of air filter is very essential in order to understand the real filtration phenomena during filter use. In this study, we investigated the effect of particle and filter charge on the particle loading property of air filter. Charged filter and uncharged filter prepared by discharging the charged filter by isopropyl alcohol were used as test samples, and three types of particle having different charge states were supplied to filters tested. For neutralized particles there was a big difference in areal mass loading rates between charged and uncharged filters due to the very small amount of particle charge, on the other hand the difference was diminished for atomized particle and finally almost vanished for corona charged particles. The pressure drop of filter loaded with corona charged particles was only half of those for neutralized and atomized particles at the same areal mass loading because of the porous structure of particle deposit formed on filter fibers, caused by the space charge effect between particles.

• The Korean Journal of Ecology
• /
• v.21 no.4
• /
• pp.389-399
• /
• 1998

this study was focused on the effects of fire on spatial change of vegetation landscape in rural region. Fire types recognized as erown fire, severe surface fire and light surface fire in order of increasing intensity were described in a fire map. GIS was introduced to understand the relationship between fire types and topographic conditions or vegetation types. We also investigated land-use type and regeneration strategies after burning. Fire intensity depended on topographic conditions and vegetation types. Special land-use type in this area was collection of edible mushroom (Tricholoma matsutake). Mushrooms had been obtained from Pinus densiflora forests existing as edaphic climax or managed artificially. Regeneration strategy in burned areas was to make sprouts from burned oak stumps. A higher density and growth rate of sprouts, as compared to those on unburned areas, facilitated vegetation succession from P. densiflora forest to oak forest and consequently led to change of landscape pattern.

• Journal of Korean Society of Rural Planning
• /
• v.3 no.2
• /
• pp.36-49
• /
• 1997

The drastic change of mountain community, which have led existing villages to a size reduction or an extinction, makes this study concentrate on finding out the new community unit as a spatial zone of dayily life and agricultural production. The communality which has played a key role in a aura settlement consistency has been focused on the socio-economic aspect till now, neglecting the spatia] nature. The settlement-communality( SC) putting a stress on the spatial aspect can be, therefore, shapec as being multi-dimensional, composed of both a horizontally areal coverage on the surface of the residential place and a vertically hierarchial relationship between settlements, by analyzing thro( elements of communality that are the economic, socio -cultural and spatial activities. The research site is located administratively in Milan-Myoun, Pyoungchang-Gun, Gangwon-Do that ha: the characteristics as a typical mountain community. The results of field survey of which the method i: to draw the activity zone from an interview with every village's head and some residents with th( prepared questionaire can be summarized as followings. Firstly, the SC in almost all villages tended to be weakened or extincted, none the less, the spatia zone of that overally enlarged and got out of natural village unit(hamlet). However the areal coverall on which the SC has an influence reaches up to the alliant domain of a few villages generally congruen with the lowest level administrative district, Secondly, the economic and social activity pattern in village life has a tendency to be directly linked with a upper central place, so that has induced the function of a central village in the middle-low settlement hierarchy to be largely shrinked. Not only the conventional residents'access to goods service but also the recent service-delivers'access to residents has gradually formed the vertical communality with direct linkage between the upper and the bottom level settlements Lastly, the enfeeblement of the SC in the lowest settlement level tends to be supplemented by enlarging the horizontal zone of the SC or especially by strengthening the vertical direct linkage system. The very this point makes the mountain community open to the external world and also makes the spatial unit of community be multi-dimensional just like a cubic.

• Journal of Korea Water Resources Association
• /
• v.44 no.3
• /
• pp.221-230
• /
• 2011

The climate change has been observed in Korea as well as in the entire world recently. The rainstorm has been gradually increased and then the damage has been grown. It is getting important to predict short-term rainfall. The Korea Meteorological Administration (KMA) generates numerical model outputs which are computed by Global Data Assimilation and Prediction System (GDAPS) and Regional Data Assimilation and Prediction System (RDAPS). The KMA predicts rainfall using RDAPS results. RDAPS model generates 48 hours data which is organized 3 hours data accumulated at 00UTC and 12UTC. RDAPS results which are organized 3 hours time scale are converted into daily rainfall to compare observed daily rainfall. In this study, 9 cases are applied to convert RDAPS results to daily rainfall data. The MAP (mean areal precipitation) in Geum river basin are computed by using KMA which are 2005 are used. Finally, the best case which gives the close value to the observed rainfall data is obtained using the average absolute relative error (AARE) especially for the Geum River basin.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.8 no.6
• /
• pp.37-45
• /
• 2008

It is expected that conditions of water resources will be changed in Korea in accordance with world wide climate change. In order to deal with this problem and find a way of minimizing the effect of future climate change, the usefulness of climate model simulation information is examined in this study. The objective of this study is to assess the applicability of GCM (General Circulation Model) information for Korean water resources management through uncertainty analysis. The methods are based on probabilistic measures of the effectiveness of GCM simulations of an indicator variable for discriminating high versus low regional observations of a target variable. The formulation uses the significance probability of the Kolmogorov-Smirnov test for detecting differences between two variables. An estimator that accounts for climate model simulation and spatial association between the GCM data and observed data is used. Atmospheric general circulation model (AGCM) simulations done by ECMWF (European Centre for Medium-Range Weather Forecasts) with a resolution of $2^{\circ}{\times}2^{\circ}$, and METRI (Meteorological Research Institute, Korea) with resolutions of $2^{\circ}{\times}2^{\circ}$ and $4^{\circ}{\times}5^{\circ}$, were used for indicator variables, while observed mean areal precipitation (MAP) data, discharge data and mean areal temperature data on the seven major river basins in Korea were used for target variables. The results show that GCM simulations are useful in discriminating the high from the low of the observed precipitation, discharge, and temperature values. Temperature especially can be useful regardless of model and season.