• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.6A
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• pp.499-509
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• 2005

The capacity of Satellite DMB(Digital Multimedia Broadcasting) system is limited mainly by the interference. So, to achieve the expected performance of Satellite DMB system and to minimize the interference from other Satellite DMB system, ACI(Adjacent Channel Interference) should be considered carefully. Satellite DMB system uses the Gap-filler for effective transmission in terrestrial environment, and the Gap-filler can use direct amplification or frequency conversion to satisfy the specific requirements. Therefore, amplified signal causes several effects on interference between System A(Eureka 147 DAB) and System E(ISDB : Integrated services Digital Broadcasting). In this paper, by using the outcome of system-level simulation considering the results of link-level simulation, we analyze the interferences between System A and System E under practical situation based on the exact parameters of ITU-R BO. 1130-4. We also propose the appropriate level of guard band and Cell Radius to optimize system capacity by adapting the spectrum mask given in the spec. and utilizing the interference analysis between System A and System E.

• Journal of Digital Convergence
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• v.16 no.11
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• pp.29-36
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• 2018

As the digital informatization society deepens, the digital divide of the information - underprivileged becomes increasingly serious social problem. In this study, we analyzed the relationship between digital informatization capacity and satisfaction level of leisure activity in low - income class. For the analysis, we analyzed the relationship between digital informatization level and leisure satisfaction level of the low income class based on the results of the digital information gap survey in 2017. As a result, it was found that there was a positive relationship between digital access and leisure activity satisfaction, such as having a wired / wireless information device at low socioeconomic level and availability of Internet access at all times. Second, digital information capacity level and leisure satisfaction level such as PC usage ability and mobile digital device utilization ability have positive (+) relationship. Third, the level of digital information utilization, such as the use of fixed and mobile Internet, also showed a positive (+) relationship with the leisure satisfaction level of the low income class. This suggests that it is necessary to provide various supports to resolve the digital divide between the low income class and the general public.

• Journal of Digital Convergence
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• v.17 no.2
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• pp.1-7
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• 2019

Our society is evolving into an aging society. The purpose of this study is to investigate how digital informatization capacity of elderly people, one of the so - called information - neglected people, affects social activities. To this end, we analyzed the relationship between digital informatization level and social activity satisfaction level of old elderly people based on the results of the digital information gap survey in 2017. As a result, it was found that there was a positive relationship between digital access and satisfaction level of social activities, such as whether elderly people have wired / wireless information devices and internet accessibility. Second, it was found that digital information capacity level such as PC usage ability and mobile digital device utilization ability had a positive (+) relationship with only social activities. Third, the level of satisfaction with social activities increased as the level of digital information utilization increased, such as whether they were using wired and mobile Internet. This suggests that the government needs a policy to resolve various information gaps that can enhance the level of digital informatization of elderly people.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.5
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• pp.655-661
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• 2020

This study examined community-centered informatization education support measures for empowerment of women with disabilities based on gender perspective.First, the 'Digital Information Gap Survey' conducted by the Ministry of Science and ICT used the 2018 'Digital Information Gap Survey' to find out the current status of the digital information gap between male and female handicapped people. The law on information education support for women with disabilities is presented.Lastly, based on the current status of informatization education support available to women with disabilities, centered on local communities, such as establishing a comprehensive women's disability support center, visiting education considering disability types, developing and supporting customized informatization education considering learning ability, and discovering community resources related to informatization. In this paper, we propose a plan to support informatization education for women with disabilities based on capacity building.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.636-644
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• 2019

The purpose of this study is to explore practical intervention strategies by identifying the relationships among digital informatization capacity, level of digital informatization accessability and life satisfaction of disabled people and to determine differences among these relationships depending on perceived level of social support networks. The participants were 1,639 disabled people from the 2017 digital information gap survey and the results, based on structural equation modeling and multi-group analysis, are as follows. First, digital informatization capacity has a positive influence on the level of digital informatization accessability(β=.65), and life satisfaction(β=.08). The level of digital informatization accessability also has positive influence on life satisfaction(β=.44). Second, the analysis result of the mediated effects of digital informatization accessability level between digital informatization capacity and life satisfaction was significant at a level (β=.29) even greater than the direct effect of digital informatization capacity on life satisfaction. Third, digital information capacity and digital informatization accessability have an influence on life satisfaction regardless of their perceived level of social support. The findings suggest that creating online environments where disabled people can enjoy leisure, culture, and social interaction with high accessibility and utility are as important as providing education for improving their digital informatization capacity.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.5A
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• pp.509-516
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• 2006

Satellite-Digital Multimedia Broadcasting(S-DMB) systems are single frequency networks which consist of a satellite and gap fillers. Though gap fillers are required to extend the coverage to NLOS(Non Line-of-Sight) area, the receiver performance can be degraded with a limited number of fingers due to the increased number of multi-paths. The paper proposes to use frequency domain equalizer(FDE) instead of conventional Rake receiver, where the guard interval is not considered in order to minimize the impact on the current S-DMB systems. Through a campaign of simulations, it is found that the proposed FDE is less sensitive to the number of gap fillers compared to the conventional Rake receiver, and can achieve a greater channel capacity in most channel environments.

• Journal of Information Processing Systems
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• v.15 no.2
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• pp.261-270
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• 2019

In order to protect secret digital documents against vulnerabilities while communicating, steganography algorithms are applied. It protects a digital file from unauthorized access by hiding the entire content. Pixel-value-difference being a method from spatial domain steganography utilizes the difference gap between neighbor pixels to fulfill the same. The proposed approach is a block-wise embedding process where blocks of variable size are chosen from the cover image, therefore, a stream of secret digital contents is hidden. Least significant bit (LSB) substitution method is applied as an adaptive mechanism and optimal pixel adjustment process (OPAP) is used to minimize the error rate. The proposed application succeeds to maintain good hiding capacity and better signal-to-noise ratio when compared against other existing methods. Any means of digital communication specially e-Governance applications could be highly benefited from this approach.

• Journal of Digital Convergence
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• v.16 no.4
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• pp.23-28
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• 2018

In recent years, activities have become more important in political activities and participation in policies. Therefore, the level of digital informatization can affect the participation in policy in the online environment. In this study, we examined how the policy activities of the disabled have a relationship with the informatization level. To this end, we analyzed the relationship between the level of digital informatization and the level of satisfaction with policy activities based on the results of the digital divide survey of 2017. The results of this study are as follows: First, it shows that the disabled people have a positive relationship with the digital access and policy activity satisfaction levels such as the possession of wired / wireless information devices and Internet accessibility. Second, it is found that digital information capacity level and income level such as PC utilization ability and mobile digital device utilization ability have a positive (+) relationship. Third, as the level of digital information utilization such as wired and mobile Internet usage increased, the level of satisfaction with policy activities also increased positively. This suggests that the government needs various information policy to increase the level of digital informatization of the disabled.

• Journal of Digital Contents Society
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• v.17 no.6
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• pp.471-477
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• 2016

ICT capacity building education in developing countries with poor infrastructure is a solution to help solve ICT gaps and improve economic performance. However, there is a clear difference between countries' geographical and industrial level in terms of geographical and industrial aspects. Therefore, it is necessary to design customized educational contents for each country according to the status of various industries in each country rather than uniform and unilateral ICT capacity building education. This should be followed by a basic understanding of the current situation. The purpose of this study is to identify the level of ICT technology and curricula for female students at Life University of Cambodia among developing countries, and to find out the subjects related to industry in that region and to propose policies for continuous operation.

• 한국가시화정보학회:학술대회논문집
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• 2003.11a
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• pp.67-70
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• 2003

Hard disk drives (HDD) in computer are used extensively as data storage capacity. The trend in the computer industry to produce smaller disk drives rotating at higher speeds requires an improved understanding of fluid motion in the space between disks. Laser sheet and digital camera was used for 2-dimensional visualization of the unsteady flow between the center pair of two co-rotating disks in air with a cylindrical enclosure (or shroud). Geometric parameters are gap height (H) between disks, and gap distance (G) between disk tip and shroud. The lobe-structured boundary between inner region and outer region was detected by inserted particles, and the number of dominant vortices was determined clearly It is found from flow visualization that the number of vortex cells can be correlated with Reynolds number based on H which is defined as $Re_H={\Omega}RH/v$ ranging from $3.18\times10^3\;to\;1.43\times10^4$, and decreases as the disk speed increases. The lobe pattern by vortex cells is changed to a circular pattern for the wide gap than narrow one.