• Journal of The Korean Association For Science Education
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• v.36 no.6
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• pp.969-978
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• 2016

The purpose of this study is to figure out gifted elementary science students' improvement in performing open inquiry after peer review. In this study, gifted fifth-grade students performed open inquiry and review of each other as peers after the inquiry. Students' inquiries were evaluated and the influences of the feedback from the peer reviews were analyzed in relation to the inquiry performances. As a result of this study, three key points were discovered: First, the evaluation score increased with frequent feedback or long discussions. On the other hand, with less feedback, the evaluation score didn't rise. Second, there were three types of improvement in inquiry related to peer review: No. 1 was improvement after feedback given by themselves. No. 2 was reflection of feedback given to other groups. As a last type, No. 3 was that the students learned from other groups' presentation without any feedback and improved their inquiry. Third, there were five kinds of giving feedback; (1) feedback understanding the inquiry correctly, (2) insufficiency of peer's inquiry without deep thought. (3) on the usefulness of the inquiry, (4) on the scientific and logic validity through critical thinking, and (5) how to develop the inquiry. In these kinds of feedback, the fourth kind of feedback (4) occurred most frequently but the fifth (5) occurred rarely. It means peer review helps students develop their critical thinking ability and teachers should encourage students to give peers feedback of the fifth kind.

• English Language & Literature Teaching
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• v.11 no.3
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• pp.1-23
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• 2005

This paper is a qualitative and quantitative study. The main purpose of the paper is to diagnose what makes English communication difficult at the Korean EFL adult level. In order to obtain data, this study employed interviews and a questionnaire. We identified thirty three factors blocking pathways to oral communication. Qualitative analysis repeatedly revealed patterns such as lack of grammar, lack of vocabulary, lack of background knowledge, and peer pressure, but quantitative analysis yielded somewhat different results: lack of colloquial expressions, lack of vocabulary, lack of various topics, problems in the educational system, difficulty in using existing knowledge, and lack of grammar. Findings which were common to both qualitative and quantitative analyses suggest that lack of linguistic knowledge and lack of background knowledge are major barriers learners encounter in communication. On the basis of the results, suggestions are made for overcoming these barriers.

• Proceedings of the Korean Information Science Society Conference
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• 2011.06d
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• pp.287-288
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• 2011

In this paper, we propose a hierarchical P2P architecture using clustering mobile peers. The proposed scheme utilizes the maximum connection time of connected peers to form the mobile network, which makes the network topology relatively stable. The connection time of connected peers can be determined by the location, velocity vector and communication range of each mobile peer. Therefore, the update overhead of the network is decreased and the success rate of contents search is increased. Experiments have shown that our proposed scheme outperforms the existing schemes.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.13 no.1
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• pp.104-116
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• 2002

This study investigated the psychosocial characteristics of children and adolescents who were addicted to internet. 1107 children and adolescents were administered several self-report inventories assessing internet addiction, internet expectancy, self-control, parent-adolescent communication, parent control of internet, peer relation, and loneliness. Results indicated that internet addicted adolescents had more expectancy for internet, less self-control, more dysfunctional communication with parents, and more withdrawn from peers than non-addicted. To determine relative contributions of these variables, multiple regression was conducted. It was demonstrated that internet expectancy, self-control, dysfunctional parentadolescent communication, and parent control of internet explained adolescent internet addiction.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.10
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• pp.2097-2104
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• 2009

In terrestrial communications, high data rate transmission can be achieved by splitting the coverage area into small cells through base stations and reusing the resource efficiently. However, the geographical features of maritime communications require the long transmission range, and it is not practical to install base station on the sea to set up the similar deployment as the terrestrial communications, so MF/HF band modem with low data rate are currently utilized for maritime communications. And the expensive satellite communication via Inmarsat is the conventional solution for the high data rate transmission on the sea. To reduce the cost, Ad-hoc network is proposed to apply on the sea, which requires no base station for the peer-to-peer communications. In this paper, we denominate this maritime environment specific Ad-hoc network as Nautical Ad-hoc Network (NANET). Furthermore, the deployment scenario for the NANET, and the analysis on multiple access and duplexing schemes for the NANET are discussed in this paper, which serves as the cornerstone for the further NANET research and development.

• Journal of the Korea Society of Computer and Information
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• v.27 no.10
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• pp.95-103
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• 2022

As 5G mobile communication services gradually expand in P2P (peer-to-peer) or D2D (device-to-device) applications, traffic-oriented stream control such as YouTube streaming is emerging as an important technology. In D2D communication, the type of data stream most frequently transmitted by users is a video stream, which has the characteristics of a large-capacity transport stream. In a D2D communication environment, this type of stream not only provides a cause of traffic congestion, but also degrades the quality of service between D2D User Equipments (DUEs). In this paper, we propose a Traffic-Oriented Stream Scheduling (TOSS) scheme to minimize the interruption of dynamic media streams such as video streams and to optimize streaming service quality. The proposed scheme schedules the media stream by analyzing the characteristics of the media stream and the traffic type in the bandwidth of 3.5 GHz and 28 GHz under the 5G gNB environment. We examine the performance of the proposed scheme through simulation, and the simulation results show that the proposed scheme has better performance than other comparative methods.

• Electronics and Telecommunications Trends
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• v.22 no.1 s.103
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• pp.11-23
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• 2007

초기에 P2P가 등장할 때만 해도 저작권, 보안 등의 문제 등으로 인해 ‘문제아’ 정도로 인식되었던 것은 사실이다, 그러나 최근 들어서는 P2P를 응용 인프라 구축을 위한 하나의 통신계층으로 보는 시각이 등장할 정도로 인터넷에서 매우 대중화된 서비스가 되어 버렸으며, 실제로 VoIP, video streaming, game 등 매우 다양한 응용의 인프라로 P2P가 사용되고 있다. 본 고에서는 이러한 P2P에 대한 표준화 및 기술 동향, 보안 취약성 및 대응 기술 등을 살펴본다.

• Journal of Internet Computing and Services
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• v.10 no.3
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• pp.51-60
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• 2009

This paper proposes a reliable 2-mode authentication framework for probabilistic key pre-distribution in Wireless Sensor Network (WSN) that guarantees the safe defense against different kinds of attacks: Hello flood attacks, Wormhole attacks, Sinkhole attack, location deployment attacks, and Man in the middle attack. The mechanism storing the trust neighbor IDs reduces the dependence on the cluster head and as the result; it saves the power energy for the authentication process as well as provides peer-to-peer communication.

• Journal of Information Processing Systems
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• v.6 no.2
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• pp.129-146
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• 2010

The trend of Next Generation Networks' (NGN) evolution is towards providing multiple and multimedia services to users through ubiquitous networks. The aim of IP Multimedia Subsystem (IMS) is to integrate mobile communication networks and computer networks. The IMS plays an important role in NGN services, which can be achieved by heterogeneous networks and different access technologies. IMS can be used to manage all service related issues such as Quality of Service (QoS), Charging, Access Control, User and Services Management. Nowadays, internet technology is changing with each passing day. New technologies yield new impact to IMS. In this paper, we perform a survey of IMS and discuss the different impacts of new technologies on IMS such as P2P, SCIM, Web Service and its security issues.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.11a
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• pp.500-506
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• 1998

This paper proposes an extension scheme of the well-known Berkeley Socket Interface for supporting QoS-provided multipeer multimedia communications. The current BSD Socket Interface has been TCP/IP-centric historically and the protocol suite was developed for the peer-to-peer best effort data communications. In order to support multiparty multimedia applications, such key functions as group management, QoS control, and reliable multicast transport should be exploited in the current simple unicast communication architecture and the well-known interface should be extended to cover the functions. This paper proposes a few new API functions and some changes in the current APIs.