• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.7
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• pp.1505-1510
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• 2014

High-Pass (ETC ; Electronic Toll Collection) system is one of the basic elements, which adopts a wireless communication method using 5.8 GHz and can realize a part of ITS (Intelligent Traffic System). On the other hand, communication errors occur frequently in Hi-Pass system due to signal erros, multi-path reflection, and/or system-to-system interferences. To solve these problems, an EM (Electro-Magnetic) wave absorber can be used. To solve these Problems, we fabricated some samples in the different composition ratios of Carbon, Sendust, and CPE, and it was confirmed that the optimum composition ratio of Carbon : Sendust : CPE is 10 : 40 : 50 wt.%. The complex relative permittivity and complex relative permeability were derived by using the measured data. In addition, the optimum design parameters for the absorber were determined by simulation. Then the absorption abilities were calculated by changing the thickness of the EM wave absorbers. As a result, the optimum thickness of the developed EM wave absorber was 2.85 mm with absorption ability over 22.4 dB at 5.8 GHz. Futhermore, the EM wave absorber was fabricated based on the simulated and designed values. The measured values agreed well with the simulated ones. Therefore, it was clearly shown that the developed EM wave absorber in this paper is to be applied in actual situations.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.14 no.3
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• pp.184-192
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• 2021

Domestic agriculture is facing real problems, such as a decrease in the population in rural areas, a shortage of labor due to an aging population, and increased risks due to the deepening of climate change. Smart farming technology is being developed to solve these problems. In the development of smart agricultural technology, irrigation control plays an important role in creating an optimal growth environment and is an important issue in terms of environmental protection. This paper is about the study of collecting and analyzing the rhizosphere environmental data of domestic paprika farms for the purpose of improving the quality of crops, reducing production costs, and increasing production. Irrigation control modeling presented in this paper Control modeling is to graphically present changes in a medium weight, feed, and drainage due to regional climatic features. To derive the graph, the parameters were determined through data collection and analysis, and the suggested irrigation control modeling method was applied to the collected rhizosphere environmental data to control irrigation in 6 regions (Gangwon-do, Chungnam, Jeonbuk, Jeonnam, Gyeongbuk, and Gyeongnam). The parameters were obtained and graphs were derived from them. After that, a study was conducted to analyze the derived parameters to verify the validity of the irrigation control modeling method and to correlate them with climatic features (average temperature and precipitation).

• Journal of Korean Society of Archives and Records Management
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• v.8 no.2
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• pp.39-60
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• 2008

This paper deals with the four aspects of the acquisition, construction and common use of modern and post-modern document DB in the NAK, NIKH, and AKS. First, The concept of Korean regional history includes provincial history, local history and regional history and as far as modern and post-modern history is concerned, the concept of regional history is on expansion. Second, National Archives of Korea has been systematically collecting and managing modern and post-modern regional history records in compliance to Public Institutes Records Management Law, enacted in 1999 and currently is in charge of handling public records of 373 central government administration offices, 514 regional government offices, Office of Education, universities and of other public agencies. National Institute of Korean History is working on a ten year project from 2004 to collect the scattered modern and post-modern regional history records and to classify them regionally and thematically. The Academy of Korean Studies has been collecting modern and post-modern regional history records and collection was initiated by Modern History Research. Those records that are collected from 1997 and 2005 are mainly from the liberation period. Third, characteristics of Central Archives Management System and Nara Records Portal System of NAK, Korean History Database System of NIKH and of The AKS' Korean Provincial Culture Electronic Encyclopedia are elaborated. Fourth, establishing 'Modern and Post-modern Regional History Records Council' as an affiliated organization of National Archives Management Committee is recommended, NAK leading the council and promoting further cooperation. In this section, an emphasis on allotted tasks of three institutes in order to achieve technology development for digitalized resource sharing, to improve on contents and to promote public and international use is placed as well.