• Journal of KIISE:Information Networking
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• v.34 no.2
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• pp.110-119
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• 2007

Mobile IPv6 (MIPv6) enables a mobile node (MN) to maintain its connectivity with a correspondent node (CN) while changing its point of attachment. In MIPv6, packets sent from a CN to a MN during handover are lost. Several mechanisms including FMIPv6 and HMIPv6 have been proposed in order to minimize packet loss. However, such mechanisms still suffer from performance degradation due to not only packet loss but also out-of-sequence packets. In this paper, we propose I-FHMIPv6 to resolve packet loss as well as the out-of-sequence packet problem. In I-FHMIPv6, the flush message is newly defined in order to notify a home agent (HA) or CN of the fact that the binding cache entry of a MN is about to be updated. A MN receiving the flush message can know that there is no more packets transmitted via the previous route, which resolve the out-of-sequence packet problem. Moreover, with the proposed mechanism, we can minimize packet loss by integrating FMIPv6 and HMIPv6 efficiently. I-FHMIPv6 is evaluated by performing simulations, and the simulation results show that I-FHMIPv6 outperforms FMIPv6 and HMIPv6.

• The Journal of the Korea Contents Association
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• v.18 no.10
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• pp.217-228
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• 2018

The purpose of this study is to observe the awareness and needs of original inhabitants on urban to rural migration and propose public projects with a consideration of their stance based on the results. To comprehend their awareness and needs on urban to rural migration through their experience related to it, focus group interview was done and three categories were identified as a result, which are 'relative deprivation', 'limitations and difficulties of urban to rural migration', and 'plans for successful settlement'. First, the original inhabitants were discontent towards the government policies related to urban to rural migration and migrant's behaviors seemed to form negative perception on it. Second, financial difficulty and trouble in stable crop cultivation and acquirement of farming techniques were identified as limitations and difficulties of urban to rural migration. Third, the original inhabitants recognized the need of direct communication between original inhabitants and migrants and activation of meetings for exchange of information to positive relationship between the two groups and migrants should have proper attitude and effort to learn the rural culture for interaction and cooperation. Fourth, there's in need for an institution, which serves as a focal point that provides information and support urban to rural migration. Fifth, successful plans for settlements of migrants thought by the original inhabitants were found. Sixth, there's a need for the original inhabitants to play the role of a mentor to the migrants for their settlement and to promote positive relationship between them.

• Journal of Korean Library and Information Science Society
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• v.48 no.2
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• pp.429-447
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• 2017

The purpose of this study is to measure the extent of collaboration by comparing team size patterns of Korean LIS journals with international LIS journals. For the sample dataset, the top 30 ranked international journals in the field of LIS were selected using the Scimago Journal Rank (SJR), and 4 Korean LIS journals were selected for the years between 2010-2016. The size of the team who authored Korean journal articles were collected from the RISS database, while the size of team who authored international journal articles from the top LIS journals were collected using the Scopus database. The result of this study shows that the most common team size ranged from one member team to three member teams. Overall, the collaborative team size in international journals was higher than Korean journals. In particular, one member team was the most common team size in Korean journals, whereas two members team was most common in the international journals. At the subject level, the most common team size was one team member in the subject area of Library Related, while the most common team size was three team members in the subject area of Science/Engineering. The result of this study suggests that within LIS, the size of teams may vary considerably due to differences in subject areas.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.77-90
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• 2013

This study is to seek measures for streamlining the evaluation system by analyzing the examples of advanced countries. This study was conducted, based on the relevant government policy documents and previous research papers, in the manner of comparing and analyzing the issues and cases regarding the government evaluation system of public-funded R&D programs in selected countries. In Korea, a national R&D performance evaluation system was introduced by law in 2006. In United States, Obama government has enhanced government performance management by signed into law the GPRA Modernezation Act of 2010. The Japanese Government issued a newly revised Guideline on National R&D Evaluation in late 2012. European Union has also been constantly updating its evaluation system for Framework Programmes(FPs) begun since 1984. This study gets some insights from the recent development of R&D evaluation in the other countries. It is important for the government R&D evaluation system to be in line with national S&T policy and agency's mission. In micro views, specific evaluation approaches and methods by types of various R&D programs should be more illustratively developed. Additionally it is suggested to monitor recent trends and techniques on R&D evaluation by participating in activities to communicate and share their knowledge and experiences in international evaluation research networks.

• Journal of Internet Computing and Services
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• v.18 no.4
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• pp.51-59
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• 2017

With the growth of Cloud computing, it is important to consider resource management techniques to minimize the overall costs of management. In cloud environments, each host's utilization and virtual machine's request based on user preferences are dynamic in nature. To solve this problem, efficient allocation method of virtual machines to hosts where the classification of virtual machines and hosts is undetermined should be studied. In reducing the number of active hosts to reduce energy consumption, thresholds can be implemented to migrate VMs to other hosts. By using Fuzzy logic in classifying resource requests of virtual machines and resource utilization of hosts, we proposed an adaptive VM allocation and migration approach. The allocation strategy classifies the VMs according to their resource request, then assigns it to the host with the lowest resource utilization. In migrating VMs from overutilized hosts, the resource utilization of each host was used to create an upper threshold. In selecting candidate VMs for migration, virtual machines that contributed to the high resource utilization in the host were chosen to be migrated. We evaluated our work through simulations and results show that our approach was significantly better compared to other VM allocation and Migration strategies.

• Journal of The Korean Association For Science Education
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• v.30 no.5
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• pp.533-543
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• 2010

This paper analyzed the improvement of cognitive level of the students and interactions which occurred in each step of free-topic scientific inquiry to help science teachers understand free-topic scientific inquiry better. Free-topic scientific inquiry is helpful to students with a deep strategic learning goal orientation type or a deep strategic ability goal orientation type in their transition (2B/3A) of cognitive levels. Most students have difficulties in the phase of establishing topics and hypotheses. The result says that the discussion techniques are improved through free-topic scientific inquiry, but the quality of interaction is not easily improved. The deep strategic learning goal orientation type concretizes opinion through interaction in free-topic scientific inquiry. The deep strategic ability goal orientation type are actively involve in the interaction, but they pay no attention to the process because they stick to the result. The surface strategic ability goal orientation type can not deepen a discussion due to high frequency of low level inquiry. However, the frequency of high level inquiry increases through free topic scientific inquiry operation. As a result, the characteristics of free-topic scientific inquiry were discussed and the educational implications of the progress of free-topic scientific inquiry and the organization of grouping were drawn.

• Journal of The Korean Association of Information Education
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• v.20 no.2
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• pp.139-150
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• 2016

The development of Smart devices has become a key influence on the changes of the school system. As Smart education is integrated and institutionalized in school systems, how it is perceived and utilized by teachers should be investigated. This study is conducted to find out the perception of the teachers on characteristics of Smart education, using qualitative research method, and to analyze importance-performance, using additional quantitative analysis. To figure out the perceptions of the attributes of Smart education by teachers, related literatures were reviewed. The 8 teachers were selected and the data on their perceptions of Smart education were collected through direct observation of class and semi-structured in-depth interview. After researching, we finally drew out 16 final concepts, 6 sub-categories, and 3 categories in the open coding process. Based on the 16 concepts on teachers' perceptions on Smart education, importance-performance analysis (IPA) were conducted to identify areas that need focus and improvement. Based on the results of teachers' perceptions on importance of and the levels of use of Smart education, recommendations were provided for better practice of Smart education in school.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.1
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• pp.28-42
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• 2009

In the wake of categorizing the design changes occurred during the period from 2004 till the first half of 2006 in Choongcheong province area, based on purpose and reason of design changes identified by the Korea National Housing Corp, it included 11 types such as the image of the apartment complex, scenic elements, consideration by the user, prevention of the defect, constructability, site conditions, incompatibility between the activities, superordinate standard, prevention of civic complaints, design details and others, along with 47 subordinate elements. And the evaluation intended to identify the corelation between the number and time of design change approval, frequency and scale of design change by type and the cost variations indicated that; firstly, enhancing the image of the apartment complex proved to be the main reason for design changes, accounting for 22% in terms of frequency and 54.9% in terms of cost variation. Secondly, the higher the increase in cost by design change aimed at improving the image of the complex, the lower the decrease in cost by design change for uncertain reasons, dubbed the inverse proportional relations, indicating that the design changes for uncertain reasons were mostly aimed at reducing the construction cost. Thirdly, with regard to the number of design change approval and the time of the initial approval, twice or less and 90 days or less before completion of the construction work, respectively, accounted for $52{\sim}53%$, indicating the design change deliberation and approval tended to have been carried out collectively in the form of ex post facto approval, which seemed to be attributable to the attempt of reducing the construction cost or budget problem, as a result of comparing with the cases in which the cost was reduced.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.35C no.12
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• pp.1-12
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• 1998

In this paper, a design and implementation of VHDL-to-C mapping in the VHDL compiler back-end is described. The analyzed data in an intermediate format(IF), produced by the compiler front-end, is transformed into a C-code model of VHDL semantics by the VHDL-to-C mapper. The C-code model for VHDL semantics is based on a functional template, including declaration, elaboration, initialization and execution parts. The mapping is carried out by utilizing C mapping templates of 129 types classified by mapping units and functional semantics, and iterative algorithms, which are combined with terminal information, to produce C codes. In order to generate the C program, the C codes are output to the functional template either directly or by combining the higher mapping result with intermediate mapping codes in the data queue. In experiments, it is shown that the VHDL-to-C mapper could completely deal with the VHDL analyzed programs from the compiler front-end, which deal with about 96% of major VHDL syntactic programs in the Validation Suite. As for the performance, it is found that the code size of VHDL-to-C is less than that of interpreter and worse than direct code compiler of which generated code is increased more rapidly with the size of VHDL design, and that the VHDL-to-C timing overhead is needed to be improved by the optimized implementation of mapping mechanism.

• Journal of the Korea Society of Computer and Information
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• v.19 no.12
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• pp.299-307
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• 2014

Nowadays, SNS media has become one of the most common and economic communication methods in the modern word. With the rapid development of communication technology, a variety of SNS media makes easier for us to reach other people everywhere and people are getting more and more reliant on them. The surge in SNS media users and SNS media diversity gets more important every day, but academic research on SNS media evaluation program is scanty. In order to present an evaluation program on the SNS media, this study selected some applicable measurement factors based on reference research, and then evaluate major SNS medias by using AHP analysis method. With these purposes, Kakaotalk, Twitter and Facebook, are the three major SNS medias that were chosen for the analysis. Through collections and analysis of usability evaluation factors about SNS quality from related literature, some factors were concluded: system quality, information quality, interface quality and service quality, to build an AHP frame. And to achieve these purposes, this study applied comprehend mutual questionnaire survey for experts and users to gather research date. Empirical studies about the results were performed using AHP method with Microsoft Office Excel 2010. In this study, the final SNS media evaluation result is that Kakaotalk ranks first of the three SNS media, Facebook is in the second place, and Twitter as least. When SNS media are evaluated, system quality, information quality, interface quality and service quality should be considered. Among all factors, service quality is the most important.