네트워크 생존성 기반 최대커버링 모델을 이용한 도시 무선 메쉬 네트워크 모델링

이건학 ( Gun Hak Lee ) 한국도시지리학회 2013 한국도시지리학회지 Vol.16 No.2

As mobile devices are widely adopted and demand on wireless infrastructure increases, the interests of local governments in building wireless networks for public Internet services are recently increasing. In this regard, this research addresses current spatial distribution of Wi-Fi zones and explores spatial disparity of access to the wireless Internet. Alternatively, we suggest an optimal network design model for city-wide wireless mesh network which enables extended geographic coverage with lower cost. By using a maximal covering model with survivability constraint(MCSC) which provides maximal service coverage and ensures reliable network performance, we derived optimal locations for wireless mesh routers in case of Seo-gu, Gwangju metropolitan. As a result of application, Wi-Fi zones in Seo-gu were mainly located along with major roads and spatially clustered in highly populated areas. Since there are duplicated service coverages, accessibility is not ubiquitous but limited to AP locations. This implies that there is a spatial disparity of the wireless Internet access within a city and thus it needs an alternative way of the network design for ubiquitous wireless communication services. From this context, the city-wide wireless mesh network applied to Gwangju metropolitan showed optimal configurations of mesh routers and maximal coverage of service in terms of the number of routers. Also, it revealed that there is a tradeoff between reliable network condition and service coverage.

방문보건서비스의 효율적 운영을 위한 방문경로 최적화 연구

이건학 ( Gun Hak Lee ),신정엽 ( Jung Yeop Shin ),조대헌 ( Dae Heon Cho ),김감영 ( Kam Young Kim ) 한국도시지리학회 2010 한국도시지리학회지 Vol.13 No.1

GIS 기반의 다기준 의사결정분석 기법을 이용한 시립 미술관 입지 적합성 분석 연구: 인천시를 사례로

이건학 ( Gun Hak Lee ),신정엽 ( Jung Yeop Shin ),신성희 ( Sung Hee Shin ) 한국도시지리학회 2010 한국도시지리학회지 Vol.13 No.3

As a critical space producing and consuming the contemporary urban cultures, the public cultural facilities should be located in the way of realizing efficiency and equity with regard to urban economic, cultural, social aspects comprehensively, and in the location decision, the systematic and analytic spatial decision making support is required. This paper analyzes and evaluates potential candidate sites for the public art museum in Incheon metropolitan city utilizing GIS-based multicriteria decision analysis. Also, this paper suggests several results of the suitability for the candidate sites according to the consolidated scenarios regarding efficiency and equity, which are commonly taken into account in many applications of the public facility siting. This scenario approach would help decision makers to make more flexible and resonable decisions. We expect that our analytical results would be a very useful reference to the actual decision process for the city museum of Incheon.

쌍대위치 이벤트들의 국지적 공간적 연관성을 평가하기 위한 방법론적 연구: 주택거래의 벡터 공간적 자기상관

이건학 ( Gun Hak Lee ) 한국경제지리학회 2008 한국경제지리학회지 Vol.11 No.4

대학 캠퍼스 주변의 와이파이 지리

이건학 ( Gun Hak Lee ) 한국도시지리학회 2012 한국도시지리학회지 Vol.15 No.2

With the rapid growing adoption of mobile devices such as smart phone and tablet PC in a daily life, Wi-Fi hotspots are tremendously being established. Although the Wi-Fi hotspots are likely to reconcentrate on highly populated areas or infrastructure concentrated areas such as office and commercial zones in general, thoughtless excessive establishment by competing major telecom companies are increasing inefficiency of access to the wireless Internet. This paper addresses the spatial distribution of Wi-Fi hotspots and signal characteristics in a micro scale, focusing on the campus surroundings with higher Wi-Fi service demand. Also, we discuss actual accessibility of the wireless internet in terms of the local conditions of wireless environment like channel interference. As analytical findings, locally densed areas were found with regard to place specific conditions, while the Wi-Fi hotspots of the campus surroundings show a globally clustered pattern. On the other hand, the analysis regarding signal or channel coverage directly related to actual connection to the wireless internet empirically shows that actual access to the wireless internet significantly differs from high densed distribution of Wi-Fi hotspots.

도시 주거지의 인터넷 서비스에 대한 공간적 접근성 측정을 위한 방법론적 연구: 조작적 효과와 공간적 불균형

이건학 ( Gun Hak Lee ) 한국도시지리학회 2008 한국도시지리학회지 Vol.11 No.1

도시 상업 공간 구조에 대한 차별화된 성별 이용 패턴 분석 -신촌 및 이화여대 상업 지구를 사례로-

신정엽 ( Jung Yeop Shin ),이건학 ( Gun Hak Lee ),김진영 ( Jean Young Kim ) 한국도시지리학회 2014 한국도시지리학회지 Vol.17 No.1

Urban commercial space has differentiated characteristics by gender, and a variety of urban activities are performed in that space. Notwithstanding the importance of understanding characteristics of urban commercial space by gender, there had been little research in both empirical and quantitative ways. In this regard, the purpose of this paper is to explore the urban commercial space by gender quantitatively. For empirical analysis, Shin-chon and Ewha Womans University areas were analyzed in terms of building transparency, spatial distribution of business and spatial structure, and land use. From the results of the analysis, we could find that the business domain for males is mainly spatially clustered in Shin-chon area, while the business domain for females dominates Ewha Womans University area in a spatially clustered form. Furthermore, significant differences of the land use pattern between two areas are likely to be related with social activities by gender.

행복주택 최적 입지 선정에 관한 연구: 다목적 공간 최적화 접근

진찬우 ( Chan Woo Jin ),이건학 ( Gun Hak Lee ) 한국도시지리학회 2015 한국도시지리학회지 Vol.18 No.2

‘Happy House’ is a kind of public rental houses which attempt to provide lower price houses and high quality housing services to young ages, which is a governmental project for universal housing and welfare. Since the project for ‘Happy House’ seeks both conflicting values, such as accessibility and economic feasibility, it fails to get significant effects by enforcement of the project. In this regard, we conducted location modeling to suggest the compromising solutions between conflicting objectives by utilizing a multiobjective spatial optimization methods. Furthermore, the additional requirement that ‘Happy Houses’ should not be concentrated in particular areas is imposed. As a result of modeling, various optimal locations are proposed in terms of priority of accessibility and economic feasibility. Additionally spatial solutions taking into account regional disparity of ‘Happy House’ provision are also presented by restricting potential siting of ‘Happy House’ by districts. Our approach has a significant contribution by approaching contextual and spatial aspects of accessibility and economic feasibility of ‘Happy House’ project in systematic and empirical ways. Also, it is expected that empirical results will help policy and decision makers who must consider various realistic situations make reasonable and flexible decisions.

SpVAR모델을 활용한 주택 매매-전세가격의 시공간적 상호작용 패턴 분석 - 수도권 주택 시장을 대상으로 -

진찬우(Jin, Chan Woo),이건학(Lee, Gun Hak) 한국부동산원 2016 부동산분석 Vol.2 No.2

본 연구는 공간적 벡터자기회귀모델(SpVAR)을 활용하여 주택의 유형별 매매가와 전세가 간의 시공간적 상호작용 패턴을 실증적으로 살펴보고, 기존의 패널 VAR모형과 비교하여 추정과 예측의 정확성을 평가하고 있다. 사례 연구로 2011년 1월부터 2015년 6월까지 수도권 65개 시군구의 주택 유형별 매매가와 전세가를 대상으로 분석한 결과, 1기 전 인접 시군구의 아파트 전세가 상승은 모든 유형의 전세가의 정적인 영향을 미치는 것으로 나타난 반면, 아파트 매매가의 경우 그 영향이 미미한 것으로 나타났다. 특히 아파트 전세가의 상승은 주변 지역 연립다세대 주택 전세가에 상대적으로 큰 파급효과를 불러일으켜, 아파트 전세가 상승이 주변지역의 연립 주택 전세가격으로 전이되고 있음을 확인할 수 있었다. 또한 SpVAR 모델이 기존의 비공간적 패널 VAR 모델에 비해 주택 가격 변화량의 방향을 보다 정확하게 예측하였다. 이러한 결과는 주택 유형별 가격의 공간적 상관성이 하위시장 가격을 결정하는 유의미한 요소로 작용하고 있으며, 특정재화의 가격이 주변 지역으로 전이되는 과정이 나타나고 있음을 의미한다. This paper analyzes the spatio-temporal interaction patterns of the house sales and rent price using SpVAR model and evaluate accuracy of estimation and prediction of suggested model, compared with panel VAR model. For the case study, we analyzed the house sales and rent price by housing types for 65 sigungu of the Seoul metropolitan area. The result shows that the 1-period former neighboring rental price of apartment has effects on all types of rental prices, whereas the sale price of apartment has little influences. Especially, the increase of apartment rental prices for a particular area substantially impacts multi-family housing rental prices for neighboring areas. This result empirically supports the spillover effect of the house sales and rent price. Also, the SpVAR model predicted the direction of the house price variation more accurately than the non-spatial VAR model. This means that the spatial association in house prices by housing type plays an important role in determining sub-market house prices, and the house price of a particular housing type influences other house prices in neighboring areas.

공간분석 및 모델링을 이용한 지방행정구역 재설정에 관한 연구

김감영(Kam Young Kim),이건학(Gun Hak Lee),신정엽(Jung Yeop Shin) 한국지역지리학회 2010 한국지역지리학회지 Vol.16 No.6

본 연구의 목적은 공간분석 및 모델링을 이용하여 지방행정구역을 재설정하는 최적화 모델을 개발하는 데에 있다. 이를 위해 먼저 기존의 지방행정체제 개편과 관련된 논의들을 비판적으로 검토하여 구역 설정을 위한 기준을 도출하였다. 도출된 기준을 바탕으로 행정구역 재설정을 위한 최적화 모델을 정의하였다. 구역내 동질성, 구역간 형평성, 공간적 배열이라는 세 가지 요소를 행정구역 재설정 최적화 모델의 주요 기준으로 고려하였다. 행정구역과 실제 생활권(경제권)을 일치시키기 위한 구역내 동질성은 구역에 포함된 단위 지역간 상호작용의 형태로 정량화되었다. 인구, 면적, 재정력 등의 차이를 이용하여 구역간 형평성을 평가하였다. 마지막으로 조밀하고 연속적인 구역이 형성되도록 공간적 배열을 제약하였다. 제시된 행정구역 재설정 최적화 모델은 GIS 환경에서 자동구획절차(AZP) 알고리즘을 이용하여 구현되었으며, 시군 공간 단위의 합역을 통한 광역체계 행정구역을 설정하는 문제에 적용되었다. 적용 결과 제시된 모델은 목적함수 대안에 따른 최적화된 구획체계를 도출하였다. The purpose of this study is to develop an optimization model for reconstructing local administrative districts using spatial analysis and modeling. For this, literature related to reorganization of local administrative systems was critically reviewed and criteria for redistricting were extracted. An optimization model for reconstructing administrative districts was formulated based on these criteria. The model considered three criteria; homogeneity within a reconstructed district, equity among reconstructed districts, and spatial arrangement. Homogeneity for relieving spatial mismatch between administrative and living(economic) boundaries is measured by spatial interaction within a district. Equity among districts is evaluated using population, area, and financial independence. Finally, spatial arrangement is measured by compactness and contiguity. The developed optimization model was implemented using Automated Zoning Procedure(AZP) in GIS environment and applied to a problem aggregating Si-Gun administrative units into broader districts. Application results demonstrate that the model can provide optimal districts according to alternative objective functions.