• Proceedings of the Korea Multimedia Society Conference
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• 2003.11a
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• pp.466-469
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• 2003

PC의 컴퓨팅 능력과 네트워크 성능이 급속도로 향상됨에 따라 이러한 인프라를 바탕으로 떠오르고 있는 Peer-to-Peer (P2P) 시스템은 자원의 복제 및 공유를 통하여 컴퓨팅 시스템 전반에 걸친 신뢰성과 결함감내 능력을 향상시킨다. 그러나 현재까지 연구된 P2P 네트워크는 각 노드가 복제한 데이터의 일관성 유지를 위해 필요한 그룹통신에 대한 고려가 부족하다. 본 논문은 SpanningTree 방식의 링 구성을 통하여, P2P 시스템에서의 그룹통신을 위해 설계된 메시지 전송 방식을 설명하고 기존 P2P 메시지 전송방식과의 비교를 통하여 성능향상의 근거를 보인다.

• International Journal of Contents
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• v.2 no.1
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• pp.1-4
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• 2006

E-business is not like e-commerce. E-business is more comprehensive than e-commerce. In the near future, it is expected that ebusiness prevails in the fields of wireless, peer-to-peer networks, streaming media and biometrics technologies. In this paper, we discuss the past and current of e-business, and then research topics of e-business, including new technology and the directions.

• Annual Conference of KIPS
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• 2021.11a
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• pp.359-362
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• 2021

자기 주권 신원 증명 기술인 DID가 강력한 인증 수단으로 떠오르고 있다. 이런 DID 기술을 사용한 DIDComm은 중앙을 거치지 않는, 사용자끼리의 통신(P2P)을 가능하게 만들어 주며, 이는 강력한 보안을 제공해 준다. 본 글은 DIDComm 기술을 활용한 P2P 메신저에 대해 작성하였다. 이를 활용한 메신저는 사용자 간의 높은 보안을 가진 통신을 제공해 줄 수 있으며 앞으로의 인터넷 시대, 메타버스 시대에서 주목할 만한 기술이다.

• Journal of Convergence Society for SMB
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• v.6 no.2
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• pp.37-43
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• 2016

Due to the remarkable improvement of ICT, with the popularization of mobile devices and every sector of society connected by networks, an era, in which peer to peer, peer to thing, thing to thing can be connected to one another everywhere, has begun. As all the electronic devices are connected to Internet, they have become more intellectualized and automated, making convergence and process of information through the connection of the devices possible to provide a lot better services. However, those devices communicate mutually to send information and they are exposed to various security threats. Therefore, this study analyzes ZigBee, CoAP, MQTT, XMPP, which are communication-related technology of IoT, draws security threats they have, and suggests requirements that components of IoT should have. Plus, it examines real cases about security threats in IoT, and suggests a countermeasure so as to contribute to establishment of a basis for IoT to be used much more safely in the future.

• The Journal of Korean Medicine
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• v.43 no.3
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• pp.49-64
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• 2022

Objectives: Peer role-play (PRP) has been used in health care training simulations because standardized patient training requires considerable time and expense. This study described the implementation of clinical simulation using PRP and examined the effect. Methods: Final year students from a single college of Korean medicine engaged in PRP as part of clinical skills practice. Education tools from clinical practice guidelines were used to structure the PRP. Communication competency was assessed with the Korean Version of the Self-Efficacy Questionnaire (KSE-12). Whether this training helped to achieve graduate outcomes was evaluated on a five-point scale. Results: Fifty-nine students (53.2%) participated in the survey. Among 12 items on the KSE-12, the score for "How certain are you that you are able to successfully listen attentively to the patient?" was the highest. Further, PRP was found to be helpful for self-directed learning, establishment of one's professional identity, and the ability to communicate and manage patients. Three themes ("Benefits of role-play", "The importance of positive feedback", "Limitations and problems of role-play"), 15 categories, and 16 central meanings were derived by categorizing learners' subjective opinions about PRP. Conclusions: Study findings indicate that PRP may contribute to improving communication skills and establishing a professional identity for future Korean medicine doctors. We suggest using PRP in clinical education in colleges of Korean Medicine.

• Journal of agricultural medicine and community health
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• v.29 no.1
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• pp.15-28
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• 2004

Objectives: This study was performed to examined the effectiveness evaluation of peer education program on smoking prevention and cessation for elementary school students. Methods: Data were collected from 60 students in a rural area through self-administrated questionnaires. Child-leaders participated the peer education program to assist their friend, parent, and adult in community to quit the smoking for 4 weeks. Results and Conclusions: Major conclusions were as follows : 1. The peer education program on smoking prevention and cessation for elementary school students was reinforce to increasing the tobacco knowledge and the cessation skill, learning the communication skill, and improving the empowerment. 2. Image of tobacco, intention of smoking in future, recommendation for smoking cessation, pro of smoking. con of smoking, and level of assert in post-test were higher than those in pre-test. 3. There were significant differences in image of tobacco, con of smoking, and level of assert by grade between the pre-test and the post-test of peer education program. But intention of smoking in future, recommendation for smoking cessation, and pro of smoking were not related to effectiveness of peer education program. 4. Child-leaders for smoking prevention and cessation performed the their task to 1.4 persons per student. 5. Participating students were satisfied with the contents of program, the usefulness of educational materials, and preference of parents, but they were not satisfied with the usefulness of task note, learning time, and lecture room.

• Journal of The Korean Association For Science Education
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• v.30 no.8
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• pp.988-1001
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• 2010

The purpose of this research was to investigate how the peer review activity of lab report in the problem-solving experiment effected on the description ability and the quality improvement. The students who were taking the general chemistry experiment course were the subjects for this study. They finished lab reports and received peer review from their peers more than two times. The students who got feedback answered on peer review, revised their reports, and subsequently, completed final reports. The result showed that peer review affected the qualitative improvement of the lab report, specially in the process of 'designing experiment' and 'drawing conclusion and evaluation'. Students could organize their thoughts through writing lab reports. During this process, peer review activities provided the opportunity of self-examination and the way for viewing as objective standpoint. Moreover, the activities established communication fields for exchanging mutual opinions and learning.

• Journal of the Korea Society of Computer and Information
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• v.10 no.4 s.36
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• pp.93-102
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• 2005

Excessive traffic of P2P applications in the limited communication environment is considered as a network bandwidth problem. Moreover, Though P2P systems search a resource in the phase of search using weakly connected systems(peers' connection to P2P overlay network is very weakly connected), it is not guaranteed to download the very peer's resource in the phase of download. In previous P2P search algorithm (1), we had adopted the heuristic peer selection method based on Random Walks to resolve this problems. In this paper, we suggested an adaptive P2P search algorithm based on the previous algorithm(1) to reform the node distribution rate which is affected in unit peer ability. Also, we have adapted the discriminative replication method based on a query ratio to reduce traffic amount additionally. In the performance estimation result of this suggested system, our system works on a appropriate point of compromise in due consideration of the direction of searching and distribution of traffic occurrence.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.1
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• pp.188-210
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• 2022

As a promising technique to support tremendous numbers of Internet of Things devices and a variety of applications efficiently, mobile edge computing (MEC) has attracted extensive studies recently. In this paper, we consider a MEC-assisted peer-to-peer (P2P) mobile communication system where MEC servers are deployed at access points to accelerate the communication process between mobile terminals. To capture the tradeoff between the time delay and the energy consumption of the system, a cost function is introduced to facilitate the optimization of the computation and communication resources. The formulated optimization problem is non-convex and is tackled by an iterative block coordinate descent algorithm that decouples the original optimization problem into two subproblems and alternately optimizes the computation and communication resources. Moreover, the MEC-assisted P2P communication system is compared with the conventional P2P communication system, then a condition is provided in closed-form expression when the MEC-assisted P2P communication system performs better. Simulation results show that the advantage of this system is enhanced when the computing capability of the receiver increases whereas it is reduced when the computing capability of the transmitter increases. In addition, the performance of this system is significantly improved when the signal-to-noise ratio of hop-1 exceeds that of hop-2.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7B
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• pp.598-612
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• 2004

Client requests have increased with the improvement of network resources at client side, whereas network resources at server side could not keep pace with the increased client request. Therefore, it is primary factor of the Qos that efficiently utilize network resources at server side. In this paper, we proposed a new model that peer-to-peer transfer scheme for partial multimedia stream based on CIWP which it decrease server network bandwidth by utilizing client disk resources saves additional server network resources. Especially, adapting Threshold_Based Multicast scheme guarantees to do that data transfer within clients never exceed service time of previous peer by restriction of which data size transferring from previous peer less than data size transferring from server. Peer-to-peer transfer within clients is limited in same group classified as ISPs. Our analytical result shows that proposed scheme reduces appling network resources at server side as utilizing additional client disk resource. furthermore, we perform various simulation study demonstrating the performance gain through comparing delay time and proportion of waiting requesters. As a result, when we compared to Threshold_Based Multicast scheme, the proposed scheme reduces server network bandwidth by 35%.