• Proceedings of the Korea Multimedia Society Conference
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• 2003.11b
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• pp.969-973
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• 2003

지리적으로 분산되어 있는 이기종의 분산 컴퓨팅 자원과 대규모 데이터를 효과적으로 활용하기 위해서 최근에 GRID 컴퓨팅 환경에 대한 연구가 매우 활성화되고 있다. 이러한 GRID 환경을 구현하기 위해 필요한 부분중의 하나가 사용자와 자원간의 인증에 관련된 문제이다. 현재 Globus Toolkit은 PKI(Public Key Infrastructure)를 기본으로 하는 보안정책을 사용하고 있다. 이 정책은 인증과정에 적지않은 오버헤드가 발생되는 문제점을 가지고 있다. 이에 본 논문에서는 사용자와 자원간의 직접적인 인증으로 인해 발생하는 성능상의 비효율성을 줄이기 위해 사용자가 자원에 접속 하기전 AIS서버(Authentification Information Server)를 이용하여 미리 인증을 거친후, 자원에 접근한 때는 기 발급된 식별자로 인증 될 수 있도록 처리해주는 메커니즘을 제안한다.

• Annual Conference of KIPS
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• 2003.11b
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• pp.1321-1324
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• 2003

지리적으로 분산된 이 기종의 유휴 자원들을 서로 연결하여 가상의 고성능 컴퓨팅 자원으로 사용하는 그리드에서 자원에 대한 접근 제어 시스템의 구축은 필수적이다. 본 논문에서는 그리드 환경 구축 시 전세계적으로 가장 많이 사용되는 Globus Toolkit 을 기반으로 하는 그리드 접근 제어 시스템을 설계 및 구현한다. 특히, 각 자원을 제공하는 사이트의 자율성을 보장하기 위해 각종 환경 설정 파일들을 이용하는 자원 접근 제어 시스템을 설계 및 구현하였다.

• Economic and Environmental Geology
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• v.4 no.1
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• pp.33-37
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• 1971

Economical evaluation of an aquifer in an unconsolidated formation is based on the physiography, geology and hydraulics in it's loci. Since each foundation is controlled by the combination of several factors, these factors in each foundation will be explained in regard to their function, contributing to the yield of ground water from aquifers.

• Convergence Security Journal
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• v.11 no.6
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• pp.31-36
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• 2011

Cloud computing is a system which efficiently utilizes resources. In this paper, we propose 2-factor authentication system combing PKI, ID_PW and location information. The proposed method improve the security of hybrid cloud systems and manage resources more safely.

• Proceedings of the KSEEG Conference
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• 2005.04a
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• pp.350-353
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• 2005

• Proceedings of the KSEEG Conference
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• 2007.04a
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• pp.615-617
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• 2007

• Journal of Internet Computing and Services
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• v.4 no.6
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• pp.13-24
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• 2003

Grid technology requires use of geographically distributed resources from multiple domains. Resource monitoring services or tools consisting sensors or agents will run on many systems to find static resource information (such as architecture vendor, OS name and version, MIPS rate, memory size, CPU capacity, disk size, and NIC information) and dynamic resource information (CPU usage, network usage(bandwidth, latency), memory usage, etc.). Thus monitoring itself may cause system overhead. This paper proposes the optimal monitoring interval to reduce the cost of monitoring services and the dynamic monitoring interval to measure monitoring events accurately. By employing two features, we find out unnecessary system overhead is significantly reduced and accuracy of events is still acquired.

• Journal of the Korean Association of Geographic Information Studies
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• v.27 no.3
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• pp.43-59
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• 2024

This study focuses on identifying the impacts of the Nowon resource recovery facility in Seoul, Korea, on the real transaction price of apartments in the neighboring areas between 2006 and 2022, and the spatial extent of the impact. Resource recovery facilities, which generate electricity and heating energy while disposing of waste, are typical unwanted facilities that have a negative impact on neighboring property prices. As direct landfilling of household waste is banned in Seoul from 2026 and nationwide from 2030, the demand for the expansion of waste incineration facilities, including resource recovery facilities, is expected to increase rapidly. In addition, social disputes related to the decline in neighboring property prices are expected to increase. This study analyses the impact of the Nowon resource recovery facility on surrounding apartment prices over a 17-year period since 2006 using hedonic price models for apartments, and finds that the Nowon resource recovery facility consistently has a negative impact on nearby apartment prices, the spatial extent of the impact is at least 1,000 meters from the facility, and the intensity of the negative impact weakens as the distance from the facility increases. The results of this study differ from recent studies finding that the spatial extent of the impact of resource recovery facilities in Seoul on surrounding property prices is limited within 500~600 meters, suggesting that a broader approach is needed to systematically manage social conflicts that are expected to increase with the growing social demand for resource recovery facilities.

• Journal of agriculture & life science
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• v.44 no.6
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• pp.15-22
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• 2010

This study was carried out to investigate the characteristics of ions in rainwater by stem flow, through fall and rainfall in Pinus thunbergii forest in Ulsan industrial complex area and Mt. Jiri area. pH of rainwater in Ulsan industrial complex area was low as compared with those in Mt. Jiri area. EC of rainwater in Ulsan industrial complex area was mainly high and there was twice difference in stemflow and through fall as compared to Mt. Jiri area. The concentration of major ions in rainwater, especially $Ca^{2+}$ and $Mg^{2+}$ in stem flow were generally high at Ulsan industrial complex area, while anions were high in the order of ${SO_4}^{2-}>{NO_3}^{-}>Cl^-$ in both areas. There was a wide difference in ${SO_4}^{2-}$ concentration in the stem flow between both areas. ${SO_4}^{2-}$ from air pollutants will result into acidification of forest soils and thereafter cause damages on forest ecosystems.

• Journal of the Korean association of regional geographers
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• v.12 no.5
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• pp.557-570
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• 2006

This study attempts to analyze the spatial disparity between supply and the demand of volunteering activities in Daegu, South Korea. The spatial disparity of volunteering activities has been strongly influenced by the residental disparity in terms of socio-economic level. The ratio of volunteers is mostly determined by income and education level that strongly impact the spatial distribution of residential area. The regional difference of ratio of volunteers is greater among Gu districts than in Dong level. The recipients for the volunteering activities have been likely to reside in a particular area within a Gu district; so, regional difference of the recipients was severe in dong level rather than Gu level. It is strongly recommended to exchange volunteers among regions to reduce the spatial disparity between the volunteers and the recipients.