• Tunnel and Underground Space
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• v.15 no.2 s.55
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• pp.129-136
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• 2005

This paper describes the implementation of rock mass rating evaluation based on genetic algorithm(GA) and conditional simulation technique to estimate RMR in the area without sufficient borehole data RMR were estimated by GA and conditional simulation technique with reflecting distribution feature and spatial correlation. And RMR determined by GA were compared with the results from kriging. Through the analysis of the results from 30 simulations, the uncertainty of estimation could be quantified.

• Journal of Korea Society of Industrial Information Systems
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• v.18 no.3
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• pp.35-46
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• 2013

In order to develop an accurate analytical model for domestic electricity demand forecasting, we propose a prediction method of the electric power demand pattern by combining SMO classification techniques and a dimension reduction conceptualized subspace clustering techniques suitable for high-dimensional data cluster analysis. In terms of electricity demand pattern prediction, hourly electricity load patterns and the demographic and geographic characteristics can be analyzed by integrating the wireless load monitoring data as well as sub-regional unit of census information. There are composed of a total of 18 characteristics clusters in the prediction result for the sub-regional demand pattern by using census information and power load of Seoul metropolitan area. The power demand pattern prediction accuracy was approximately 85%.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.107-110
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• 2006

국가 환경방사선/능 자동감시망과 원전주변의 환경방사선/능 감시를 통해서 연속적으로 측정 기록된 대량의 환경방사선/능 정보들이 효과적으로 활용되고 있지 않는 상황에서 환경방사선/능 정보에 내재되어 있는 공간정보 속성들을 정량적으로 해석하고 시공간적으로 예측할 필요성이 있다. 지구통계기법을 활용하면 환경방사선 감시설비가 비록 설치되어 있지 않은 지점일지라도 환경방사선/능 정보에 대한 예측이 가능하므로 향후 추가적인 감시기의 설치와 시료분석에 소요되는 시간과 비용을 절감할 수 있다. 본 연구에서는 고리, 월성, 영광, 울진 원자력발전소와 대전 한국원자력연구소 등 국내 원자력이용시설 주변 토양중의 환경방사능 분포를 감마동위원소인 $^{137}Cs$과 $^{40}K$을 중심으로 파악하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2021.11a
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• pp.476-479
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• 2021

DBMS 파라미터 튜닝이란 데이터베이스에서 제공하는 다양한 파라미터의 값을 조율하여, 최적의 성능을 도출하는 과정이다. 데이터베이스 종류에 따라 파라미터 개수가 수십 개에서 수백 개로 다양하며, 각 기능이 모두 다르기 때문에 최적의 조합을 찾는 것은 쉽지 않다. 선행 연구에서는 BO 기법을 사용하여 적절한 파라미터 값을 추출했지만, 파라미터 개수에 비례하여 차원이 커지는 문제가 발생한다. 본 논문에서는 통계적으로 파라미터를 분류하여 탐색 공간을 줄인 다음 단계적으로 BO 를 수행하는 PBO 방식을 제안한다. 파라미터 값을 랜덤하게 할당하여 벤치마킹한 결과값을 군집화한 후, 각 군집별로 파라미터와의 연관성을 분석해 높은 상관관계를 가진 파라미터를 매칭시켜 분류한다. 제안하는 방법론을 검증하기 위하여 8 가지 회귀 모델과의 비교 실험을 통해 제안한 방법론의 우수성을 검증하였다.

• Journal of the Korean Association of Geographic Information Studies
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• v.17 no.2
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• pp.1-14
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• 2014

In this study, the change characteristics of urban spatial structure in Daegu were analyzed connecting with urban planning for efficient urban management. Urban development process from 1970 to 2010 in Daegu was analyzed utilizing Getis-Ord $G_i^*$ methodology, a spatial statistical method, and it was identified that Daegu was in the stage of disurbanization. However, as Daegu orients multi-nuclei city, it was difficult to explain the stage of urban development after disurbanization in 2000. Accordingly, to analyze detailed changes in spatial structure in multi-centric areas after 2000, population, land price and employment factor changes were analyzed using Bachi Measurement. According to analytical results, multi-centralization process has been continued in Daegu. Urban core area and Chilgok area showed spatial structure change into distribution process, Ansim area into concentration process, and Seongseo and Talseo area into concentration and distribution process. Therefore, urban planning considering the regional characteristics are needed for efficient urban management.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.1
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• pp.81-98
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• 2024

This study analyzed the impact of urban spatial factors on the thermal environment. The personal thermal sensation was set as the unit of thermal environment to analyze its correlation with environmental factors. To collect data on personal thermal sensation, Living Lab was applied, allowing citizens to record their thermal sensation and measure the temperature. Based on the input points of the collected personal thermal sensation, nearby urban spatial elements were collected to build a dataset for statistical analysis. Logistic regression analysis was conducted to analyze the impact of each factor on personal thermal sensation. The analysis results indicate that the temperature is influenced by the surrounding spatial environment, showing a negative correlation with building height, greenery rate, and road rate, and a positive correlation with sky view factor. Furthermore, the road rate, sky view factor, and greenery rate, in that order, had a strong impact on perceived heat. The results of this study are expected to be utilized as basic data for assessing the thermal environment to prepare local thermal environment measures in response to climate change.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.2
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• pp.83-94
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• 2020

Busan Metropolitan City, a research site of this study, was promoted to a metropolitan city in 1995 with the implementation of the local autonomy system, and the overall change was made as it absorbed the surrounding areas to address the shortage of population and space. Twenty-five years after the introduction of the local autonomy system, it is necessary to diagnose whether balanced development of the entire city is being made in accordance with the reorganization of the metropolitan city in terms of spatial structure. In this study, changes in spatial structure and regional characteristics were analyzed by applying population potential, which means potential for future spatial interaction, in time and space. According to the analysis, the development was taking place around the center area and the sub-center established by the urban master plan, but Gangseo-gu and Gijang-gun, which were incorporated in the past, remained stagnant. In addition, it was shown that the spatial expansion of the city was suppressed by the green belt surrounding the city. However, in other regions where the green belt is located, the city has been expanded, which is different from Gijang-gun or Gangseo-gu, which was incorporated into the metropolitan city. Therefore, the cause of the decline in incorporated areas should not be limited to the institutional dimension of land use regulation. Growth management and balanced development plans will be necessary for the development of declining old downtowns and underdeveloped incorporated areas.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.1
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• pp.52-66
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• 2024

The purpose of this study is to identify the spatial system and characteristics of the urban center by deriving the boundaries of the urban center set in the urban basic plan for Busan Metropolitan City and diagnosing the role and status of the center. To this end, four indicators representing the characteristics of the center were selected through a review of previous studies, and the boundaries of the center were derived using spatial statistical techniques with strengths in geographical boundary analysis. Then, using the indicators of center characteristics and population potential functions, we diagnosed the influence and potential of each center in the spatial structure of Busan Metropolitan City. The analysis showed that the scale of the centers varies greatly, and the unutilized areas where commercial areas are not activated and the expansion areas that spread beyond commercial areas to residential and industrial areas are different for each urban center. The results of the potential measurement, which indicates the attractiveness of the center, also showed areas with strong and weak population potential. Therefore, systematic management and strategies based on the hierarchical characteristics and influence measurement results are needed to strengthen the function of urban centers. The results analyzed in this study can be used as a resource for responding to various urban planning needs and policy changes in the future, along with station area development plans and spatial innovation zones for building a sustainable urban growth system, balanced development, and strengthening the function of centers.

• Geophysics and Geophysical Exploration
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• v.12 no.4
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• pp.309-315
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• 2009

Integrated interpretation of multi-geophysical data has been continuously used in terms that it has provided more confident information than the result from single-geophysical data. Especially, geostatistical integration has its own superiority that it is possible to deal with spatial characteristics as well as physical properties of survey data and the process of integration is clear. This paper further extends the previous work of geostatistical inversion for integrated interpretation. In this paper, we propose a new way of dealing with the case that the multi-geophysical data do not share the measurement range. According to the geostatistical kriging, the closer between the measurement points, the smaller kriging variance we get, and vice versa. We used this spatial properties as a weighting value to the process of geostatistical inversion for the geophysical data integration. An objective way to integrate different kinds of geophysical data measured at different ranges is provided with this algorithm.

• Journal of Korea Water Resources Association
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• v.39 no.8 s.169
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• pp.669-676
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• 2006

Hydrological factors, especially the spatial distribution of interpretation on precipitation is often topic of interest in studying of water resource. The popular methods such as Thiessen method, inverse distance method, and isohyetal method are limited in calculating the spatial continuity and geographical characteristics. This study was intended to overcome those limitations with improved method that will yield higher accuracy. The monthly and yearly precipitation data were produced and compared with the observed daily precipitation to find correlation between them. They were then used as secondary variables in Co-kriging method, and the result was compared with the outcome of existing methods like inverse distance method and kriging method. The comparison of the data showed that the daily precipitation had high correlation with corresponding year's average monthly amounts of precipitation and the observed average monthly amounts of precipitation. Then the result from the application of these data for a Co-kriging method confirmed increased accuracy in the modeling of spatial distribution of precipitation, thus indirectly reducing inconsistency of the spatial distribution of hydrological factors other than precipitation.