• 천문학논총
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• 제21권2호
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• pp.87-94
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• 2006

The COREA (COsmic ray Research and Education Array in Korea) project aims to build a ground array of particle detectors distributed over Korean Peninsular, through collaborations of high school students, educators, and university researchers, in order to study the origin of ultra high energy cosmic rays. COREA array will consist of about 2000 detector stations covering several hundreds of $km^2$ area at its final configuration and detect electrons and muons in extensive air-showers triggered by high energy particles. During the intial phase COREA array will start with a small number of detector stations in Seoul area schools. In this paper, we have studied by Monte Carlo simulations how to select detector sites for optimal detection efficiency for proton triggered air-showers. We considered several model clusters with up to 30 detector stations and calculated the effective number of air-shower events that can be detected per year for each cluster. The greatest detection efficiency is achieved when the mean distance between detector stations of a cluster is comparable to the effective radius of the air-shower of a given proton energy. We find the detection efficiency of a cluster with randomly selected detector sites is comparable to that of clusters with uniform detector spacing. We also considered a hybrid cluster with 60 detector stations that combines a small cluster with ${\Delta}{\iota}{\approx}100m$ and a large cluster with ${Delta}{\iota}{\approx}1km$. We suggest that it can be an ideal configuration for the initial phase study of the COREA project, since it can measure the cosmic rays with a wide range energy, i.e., $10^{16}eV{\leq}E{\leq}10^{19}eV$, with a reasonable detection rate.

• 한국농촌건축학회논문집
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• 제13권1호
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• pp.63-70
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• 2011

This study is about characteristic of rural areas development project considering Rural Areas Migration. As a Rural Economy is getting worse for a rapid decrease in population and a rapid aging of the population, Decline in Rural areas has become more serious. So, Each local government is promoting rural areas development project, like Culture Village Project, Rural Village Project, Happiness Village Project, and Farming and Fishing New-town Project, to attract inhabitants in the Urban Area. This study examines the change of policy about rural areas development project in Corea through theoretical study, and analyzes the Implementation of rural village Project supported or implemented by local community to characterize the project.