• The Bulletin of The Korean Astronomical Society
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• v.45 no.1
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• pp.29.4-29.4
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• 2020

Structure in the universe forms hierarchically with the small scales forming first and merging into larger scales. Galaxy clusters are at the pinnacle of the formation process. Peering far into the universe, we can observe galaxy clusters early in their evolution. SpARCSJ1049+56 is a galaxy cluster located at a redshift of 1.71. It has been shown to be rich in cluster galaxies, to have intense star formation, and to have a significant amount of molecular gas. Through careful control of systematics, we detected the weak-lensing signal from this distant galaxy cluster. I will present our HST infrared weak-lensing detection of the cluster with a focus on the method. Our lensing analysis found that the cluster is massive and is rare in a LambdaCDM universe. I will also present the Chandra X-ray discovery of cold gas coincident with the intense star formation and discuss the implications of the detection.

• Journal of the Korean housing association
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• v.16 no.1
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• pp.1-9
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• 2005

The purpose of this study is to scrutinize forefathers' standpoint on architectural planning by peering into their literature. Dongkukyisangkukjib which contains works about daily life of Lee Gyu-Bo, a great writer in the middle of Koryo, reveals well people of Koryo' thought on architecture, if we have a interest in a building space. The book holds his general viewpoint on architecture and documents about the remarkable houses he and his friends visited. Then we can know, through it, general thought on architecture of the upper classes in those days. Lee Gyu-Bo considered a house the other self of its owner and connected buildings with personality of their owner. 0 architectural process and architectural planning, buildings were shown variously by reflecting owner's value on architecture. Unlike Chosun era, people of Koryo prefer unlimited thinking to form or order. Therefore in construction especially such as a pavilion, there were many experimental tries which reflected owners' thought. Particularly we could estimate people of Koryo' conception of architectural design through a work of Lee Gyu-Bo, Saryunjungky, a document about a pavilion carrying four wheels, which describes concretely contents of architectural planning such as a planning of space, module, and intention.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.9
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• pp.497-503
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• 2016

Eco-friendly biocide that do not have noxious chemicals, have a role of disinfection adding of dispersion and strengthening peer power on RO membranes surfaces. Eco-friendly biocide show an 93% improvement of differential pressures arrival time. Also, eco-friendly biocide's Autopsy result show less the percentage of organic pollutants than currently in using biocide. Adding dispersion & peeling strength power to remove the microorganisms is upgrading. Eco-friendly biocide that have a dispersion and peering power is non-toxicant chemicals and is safe for user.

• Journal of Ocean Engineering and Technology
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• v.11 no.1
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• pp.10-15
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• 1997

Copper and its alloy had been used widely because of its pronouncing characteristics on their high thermal and electrical conductivity. Various fusion welding methods, such as SMAW, SAW, GTAW, GMAW, Electroslag welding amd so on are applied to weld copper and its alloy. But fusion welding of copper has so many welding problems. THe most serious problems were poor penetration amd high thermal contration stress due to its high thermal conductivity and porosity could be formed by rapid cooling rate of fusion welding. In order to avoid such fusion welding problems, preheating, peering and heat treatment must be applied to obtain sound weld joint of copper. But preheating induce another welding problem such as grain coarsening of weld heat affected zone. This grain coarsening reduces ductility and strength of weld joint. In this view of point, friction welding of copper is triedm to obtain sound weld joint of copper by reducing metallurgical problems. This study introduced new concept of heat input for evaluating the friction weldability of copper. As a result, weldability of copper could be evaluated by this new concept of heat input.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.376-380
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• 2009

Peer-to-Peer content delivery technology recently begins to be used not only for file sharing applications such as eDonkey but also for every kind of content services. KBS, a broadcasting company in Korea, is aggressively driving to apply Peer-to-Peer technology to KBS's commercial internet video service but we found that there are two big huddles. First, end users may refuse to share their own resources for KBS's cost reduction using Peer-to-Peer content delivery technology. Second, it may cause that the number of free-riders increases and the efficiency of the overall system would fall. From commercial service provider's perspective, we have to avoid that end users have unfavorable impressions on the service and the usefulness of Peer-to-Peer technology decreases. In order to overcome these problems, we studied how to offer incentive to end users and how much incentive would be reasonable, and then applied the result to real service for verification.

• The KIPS Transactions:PartC
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• v.10C no.2
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• pp.185-190
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• 2003

Bluetooth communication is based on piconet, which is composed by one master and maximum seven slaves. Several piconets can be interconnected via an inter-piconet Bluetooth unit called a bridge unit to form a Bluetooth scatternet. This bridge node can make its presence in each piconet by switching. This switching must be carefully scheduled so that slot wastage and, hence, packet delays are minimized. In this paper, we introduce an efficient inter-piconet scheduling scheme based on sniff mode. This scheme tries to minimize the wastage of slots by having the bridge unit sniff with its peering masters with time limits and communicate with its slaves in remaining slots. The sniff time limits are determined adaptively based on the amount of traffic in each piconet. Simulation results show this scheme outperforms round-robin scheme based on sniff intervals of equal lengths.

• Journal of Families and Better Life
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• v.26 no.1
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• pp.31-49
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• 2008

This study has been performed to explore verbal and behavioral expression of sexual desires among male elderly residents who have been living in long tenn care facilities. There are three topics covered in this study; first, in what situations and how seriously do care workers encounter expression of sexual desires of the elderly residents? Second, what kind of negative consequences do they believe those sexual behaviors will lead to? Third, how can we implement defensive measures against the sexual behaviors? In this study, twenty three care workers working full time in five retirement and care facilities were asked about their experience and perception of the above study agendas, and answers of the qualitative interview were drawn as follow; first, the elderly residents apparently show a variety of sexual harassment and provoking behaviors such as sticking to specific women, physically touching and attacking, and induce obscenely activities against female residents, care workers, and volunteer visitors. Second, their sexual behaviors are often influenced by their isolated and abandoned emotionality as well as living situation in rural areas. Third, their sexual behaviors often critically affect care work plan and facility managements by severely discouraging female care givers and community supporters. Therefore in this study, suggestions and defensive measures were made as follows: first, education and counselling programs toward female workers and volunteers need to be developed, and the programs should cover psychological and behavioral mechanism of sexuality in later life. Second, self control plans need to be empowered toward the elderly residents; in the plans, the elderly residents shall be encouraged to evaluate primary cause and proper solutions of sexual behaviors of their peering residents. Third, combination of healthy housing and care facilities for frail elderly need to be integrated in a neighboring location, so that when residents and workers encounter extreme episodes of sexuality of healthy residents in a housing facility, the problematic sexual residents are partially transferred into a neighboring care facility and thereafter other residents and cafe givers are relieved from stressful contacts with the extremely sexual residents.

• The Journal of Korean Association of Computer Education
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• v.16 no.3
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• pp.61-70
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• 2013

In order to increase students' academic achievement effectively and at the same time to draw active participations from students during the computer lab, we applied the reciprocal peer tutoring education model. We focused on a short-term application of the reciprocal peer tutoring to computer operating system lab education with as little preparation as possible. 61 college students majoring in computer engineering participated in this research; half of them studied in the reciprocal peer tutoring setting, and rest of them did in the normal lab setting. Results show that students who participated in the reciprocal peering tutoring lab have higher academic achievement and better satisfaction on overall education and the class's professor. We hope that our method will be easily used in other universities' computer lab education.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.4
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• pp.678-691
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• 2015

Internet and mobile traffic continues to surge exponentially in recent years due to popularization of smart devices, the appearance of various internet services carrying large amount of traffic from richer content and applications. This phenomenon leaded to various network problems such as the congestion delay, the non-balanced traffic ratio between ISPs, the continuous network investment cost and the Internet access problems. In light of changed data-driven communication ecosystem, There are growing concerns by both academia and industry that settlement-free peering and full transit regime have the limitations such as not only difficulties in maintaining mutual benefits but also difficulties in securing investment incentives for upgrading network performance and quality. Thus, it becomes more necessary for introducing the evolved internet interconnection regime which can fulfill the All-IP network environment. This study derives core issues regarding internet interconnection regime in Korea and suggest new evolved alternatives based on three point of view(traffic optimization, cost optimization, network investment optimization) through the empirical analysis.

• Asia Pacific Journal of Business Review
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• v.1 no.1
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• pp.67-88
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• 2016

This study aims to help address concerns about the growing demand of wider bandwidth Internet connection in the Philippines. Using articles and research of international organizations and content from official websites of the Philippine government, this paper has carefully examined the slow Internet connectivity and the high cost that the end-users pay for it. This paper suggests that this inefficiency hampers the motivation of users to innovate in a way that could contribute to inclusive growth and the development of an inclusive information society. Through a comparison of the current global ICT situation with the current situation in the Philippines, this paper shows that the country's Internet infrastructure lags behind among those of contemporary developing countries in Asia, particularly in terms of Internet connectivity. In 2015, Thailand had an average Internet speed of 7.4 Mbps, Sri Lanka 7.4, and Malaysia 4.3. Meanwhile, the Philippines had a meager average Internet speed of 2.8 Mbps, placing the country at 104 among 160 countries, with developed countries in Asia such as South Korea (23.6 Mbps) and Singapore (12.9 Mbps) ranking 1 and 12, respectively. Findings show that the lack of competition in the Internet connectivity market, among other reasons, is at the root of the dilemma of slow and costly Internet connection. Assessing the accomplishments of the Republic of Korea and other broadband-leading countries has provided practical insights and recommendations that can promote competitiveness. Furthermore, related literature argues how ISP practices may affect Internet speed and cost. This study offers an approach in improving Internet connectivity in the Philippines by bridging the gap between the Internet infrastructure market and government policies.