• 한국지리정보학회지
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• 제25권4호
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• pp.200-209
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• 2022

실시간 위치 정보를 제공하는 것이 국가산업의 주요한 목표로 부상하고 있는 실정이다. 이러한 실시간 위치 정보(3차원 공간 정보)를 제공하기 위해서는 위성 측위 방법의 기술 발달이 필수적이다. 그래서 국가에서는 Network RTK GNSS방식을 도입하여, 수요자의 요구에 만족도를 증가시키는 노력을 지속적으로 하고 있다. 본 연구에서는 국토지리정보원에서 제공하고 있는 Network RKT GNSS(Global Navigation Satellite System) 방식 중 VRS(Virtual Reference Station)과 FKP(Flachen-Korrektur Parameter)을 이용하여 통합기준점에서 연속 관측과 단독 관측을 측량하여 정확도 평가를 하였다. 또한 현장에서 급속하게 증가하고 있는 Network RTK GNSS 방법에 대하여 정확도를 제시하여 효율성을 극대화하고자 한다.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2005년도 가을 학술발표논문집 Vol.32 No.2 (1)
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• pp.394-396
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• 2005

IEEE 802.11를 비롯한 여러 무선 네트워크에서는 multi-rate을 활용한 시스템 성능향상에 관한 연구가 진행되고 있다. 그 중에 한가지 연구결과로 제안된 방법이 rDCF.이다. 만약 Mesh 네트워크에서 rDCF를 동작시킨다면, 시스템 throughput의 증가, Packet delay의 감소와 항께 채널상태에 따라 포워딩 전략을 다르게 함으로써 채널 error의 영향이 줄어들 것으로 기대해 볼 수 있다. 하지만 기존의 rDCF를 아무런 revision 없이 Mesh 네트워크에 적용하기에는 spatial reuse 측면에서 비효율적이다. Mesh 네트워크에서는 외부 네트워크와 access point 지점이 되는 portal쪽으로 traffic이 집중되는 것이 일반적이므로 portal에 가까울수록 traffic간의 contention도 가중되므로 시스템 전체 성능에 영향을 미치게 된다. 이러한 문제를 줄이기 위하여 무선 네트워크 환경에서 spatial reuse 측면을 향상시킴으로써 동시에 진행되는 communication 수를 늘리는 방법이 있다. 그러므로 본 논문에서 rDCF의 spatial reuse를 늘임으로써 좀더 Mesh Network위에서도 효율적으로 작동할 수 있는 기법을 제시하고자 한다.

• 한국멀티미디어학회논문지
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• 제11권12호
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• pp.1697-1705
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• 2008

Several studies made for wireless mesh networks aim to optimize the capacity for wireless networks. Aside from protocol improvements, researches were also done on the physical layer particularly on modulation techniques and antenna efficiency schemes. This paper is concerned with the capacity improvements derived from using spatial diversity with smart adaptive array antennas. The use of spatial diversity, which has been widely proposed for use in cellular networks in order to lessen frequency re-use, can be used in mesh networks both to minimize co-channel interference (CCI) and enable multiple transmissions. This paper aims to study the capacity region and bounds in using smart antennas for single-channel multi-radio systems in relation to the number of spatial diversity or sectors as defined by the beam angle $\beta$.

• International Journal of Advanced Culture Technology
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• 제9권3호
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• pp.23-33
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• 2021

"China's Western Development Policy" has brought multiple opportunities to the development of tourism in Southwest China including Sichuan, Guizhou, Yunnan, Chongqing and Tibet. The 4 provinces and 1 municipality overall show a certain degree of accumulation effect and coordinated development in tourism due to their location, traffic and traditional economic cooperation. This study takes the Southwest China as the research object and utilized the spatial dislocation model and the tourism spatial misalignment index to estimate the mismatch degree between tourism resources and tourism income among provinces and try to find out the internal reason background. The results show that each of the five provinces has its own advantages in index of economy, tourism resources, human resource, and transportation, leading to differences in the center of gravity of the entire region in all aspects. In view of the results of spatial dislocation analysis, suggestions for improvement and optimization are put forward to promote the high-quality development of tourism in Southwest region. development.

• 대한지리학회:학술대회논문집
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• 대한지리학회 2006년도 연례 학술대회
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• pp.61-63
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• 2006

• 한국공간정보시스템학회:학술대회논문집
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• 한국공간정보시스템학회 2002년도 제1회 국제 LBS 기술 워크샵
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• pp.75-100
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• 2002

• 한국측량학회지
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• 제38권5호
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• pp.487-496
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• 2020

This study introduces how GISs (Geographic Information Systems) are used to assess spatial disparities in urban green spaces in the Chicago. Green spaces provide us with a variety of benefits, namely environmental, economic, and physical benefits. This study seeks to explore socioeconomic relationships between green spaces and their surrounding communities and to evaluate spatial disparities from a variety of perspectives, such as health-related, socioeconomic, and physical environment factors. To achieve this goal, this study used spatial statistics, such as optimized hotspot analysis, network analysis, and space-time cluster analysis, which enable conclusions to be drawn from the geographic data. In particular, 12 variables within the three factors are used to assess spatial disparities in the benefits of the use of green spaces. Finally, the variables are standardized to rank the community areas and identify where the most vulnerable community areas or parks are. To evaluate the benefits given to the community areas, this study used the z- and composite scores, which are compared in the three different combinations. After identifying the most vulnerable community area, crime data is used to spatially understand when and where crimes occur near the parks selected. This work contributes to the work of urban planners who need to spatially evaluate community areas in considering the benefits of the uses of green spaces.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.298-301
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• 2004

The aim of this study is to cross-validate of spatial probability model, artificial neural network at Boun, Korea, using a Geographic Information System (GIS). Landslide locations were identified in the Boun, Janghung and Youngin areas from interpretation of aerial photographs, field surveys, and maps of the topography, soil type, forest cover and land use were constructed to spatial data-sets. The factors that influence landslide occurrence, such as slope, aspect and curvature of topography, were calculated from the topographic database. Topographic type, texture, material, drainage and effective soil thickness were extracted from the soil database, and type, diameter, age and density of forest were extracted from the forest database. Lithology was extracted from the geological database, and land use was classified from the Landsat TM image satellite image. Landslide susceptibility was analyzed using the landslide­occurrence factors by artificial neural network model. For the validation and cross-validation, the result of the analysis was applied to each study areas. The validation and cross-validate results showed satisfactory agreement between the susceptibility map and the existing data on landslide locations.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.710-712
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• 2006

The aim of this study was to analyze limestone deposits potential using an artificial neural network and a Geographic Information System (GIS) environment to identify areas that have not been subjected to the same degree of exploration. For this, a variety of spatial geological data were compiled, evaluated and integrated to produce a map of potential deposits in the Gangreung area, Korea. A spatial database considering deposit, topographic, geologic, geophysical and geochemical data was constructed for the study area using a GIS. The factors relating to 44 limestone deposits were the geological data, geochemical data and geophysical data. These factors were used with an artificial neural network to analyze mineral potential. Each factor’s weight was determined by the back-propagation training method. Training area was applied to analyze and verify the effect of training. Then the mineral deposit potential indices were calculated using the trained back-propagation weights, and potential map was constructed from GIS data. The mineral potential map was then verified by comparison with the known mineral deposit areas. The verification result gave accuracy of 87.31% for training area.

• 전자공학회논문지B
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• 제32B권1호
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• pp.127-135
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• 1995

The diffusion neural network forms a Gaussian distribution by transferring an excitation to the surround. A DOG(difference of two Gaussians) is obtained by the diffusion neural network. This type of the DOG, which can detect the intensity changes of an image, has the same shape as a LOG(Laplacian of a Gaussian:${\Delta}^2$G) and narrow band pass characteristics. In this paper we show that another type of the DOG which has a very narrow Gaussian for the excitatory and a very wide Gaussian for the inhibitory, can be formed by the diffusion process of this network, This type of the DOG has a wide band width in spatial frequency domain and can be used efficiently in detecting special type of edges.