• Journal of the Korean Society for information Management
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• v.30 no.3
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• pp.273-296
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• 2013

The purpose of this study is to examine the data coverage and citation threshold for analyzing SPLC(Search Path Link Count) as a main path of a historiograph of a certain topic in order to provide 'core' papers of global research trends to a researcher affiliated with a local R&D institution. 5 datasets were constructed by retrieving and collecting 2,318 articles on RGB LED on Web of Science published from 1990-2013 and 20,109 articles which cited these original 2,318. The SPLC analysis was performed on each dataset by increasing the threshold of citation counts, and the changes and resilience of the 28 extraced networks were compared. The results of user feedback on 198 unique core papers from 28 SPLC networks received from LED researchers affiliated with a Korean government-sponsored research institution were also analyzed. As a result, it is found that the nodes in each SPLC network in each dataset were differentiated by the citation counts, while the changes in the structure of SPLC networks were slight after the networks' citation counts were set at 40. Additionally, the user feedback showed that personalized research interest generally matched to the global research trends identified by the SPLC analysis.

• The KIPS Transactions:PartC
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• v.10C no.7
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• pp.943-954
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• 2003

The mobile telecommunication system has been growing exponentially after 1990s due to the high population in a city and the growth of mobile user. In this time, the current mobile system mainly concentrates on the voice communication. However, in the next generation, mobile users want to get very diverse services via mobile terminal such as the Internet access, web access, multimedia communication, and etc. For this reason, the next generation system, such as the UMTS (Universal Mobile Telecommunication Services) system, has to support the packet data service and it will play the major role in the system. By the way, since the Web service is based on TCP, most of the Internet traffic TCP traffic. Therefore, efficient transmission of TCP traffic will take very important role in the performance of packet data service. There are many researches about improving TCP performance over wireless network. In those schemes, the UMTS system adapts the link layer retransmission scheme. However, there are rarely studies about the exact performance of the link layer retransmission scheme in the face of dynamic changes of wireless environment over the UMTS system. The dynamic changes of wireless environment, such as wireless bandwidth, can degrade TCP performance directly. So, in this paper, we simulate and analyze the TCP performance in the UMTS system with dynamic wireless environments. Then, we propose a simple scheme for minimizing TCP performance degradation. As a result of simulation, we can find that when wireless environment is changed dynamically, the probability of TCP timeout is increased, and the TCP performance is degraded very much. In this situation, the proposed simple scheme shows good performance. It saves wireless resources and reduces the degradation of TCP performance without large overhead of the base station.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.7
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• pp.2512-2531
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• 2014

We propose a new Distributed Denial of Service (DDoS) defense mechanism that protects http web servers from application-level DDoS attacks based on the two methodologies: whitelist-based admission control and busy period-based attack flow detection. The attack flow detection mechanism detects attach flows based on the symptom or stress at the server, since it is getting more difficult to identify bad flows only based on the incoming traffic patterns. The stress is measured by the time interval during which a given client makes the server busy, referred to as a client-induced server busy period (CSBP). We also need to protect the servers from a sudden surge of attack flows even before the malicious flows are identified by the attack flow detection mechanism. Thus, we use whitelist-based admission control mechanism additionally to control the load on the servers. We evaluate the performance of the proposed scheme via simulation and experiment. The simulation results show that our defense system can mitigate DDoS attacks effectively even under a large number of attack flows, on the order of thousands, and the experiment results show that our defense system deployed on a linux machine is sufficiently lightweight to handle packets arriving at a rate close to the link rate.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.6
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• pp.797-804
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• 2002

As internet use is being generalized central of WWW(World Wide Web) service of multimedia based recently, we could acquire many informations that exist to all over the world's computer network .Therefore, picking up of information became important problem before that internet is generalized, but it is risen to important problem to acquire correct information rapidly on modem society that use of internet is generalized. This paper designed internet search engine and understand structure of internet search engine drawing URL that is optimized, and secure embodiment technology using Java that is language of object base. Search engine that proposed in this paper maintained user's the convenience by offer keyword search, and simplify user interface And although quantity of searched information site is few, search engine show that the bad link rate of searched result is improved compare with existent domestic manufacture search engines.

• Journal of Information Management
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• v.33 no.4
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• pp.85-105
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• 2002

The purpose of this study is to review the expanded role of authority files, which uses the Knowledge Organization System(KOS) to organize contents and manage the collections in digital libraries. The KOS plays a role as a bridge between the users' information needs and materials by providing links between catalogs and digital resources on the web and supporting retrieval of the relevant items. It is described how a KOS can be used to link a digital resource to related materials, to provide more descriptive records for entities, and access to relevant physical objects.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.8
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• pp.3028-3039
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• 2015

Recently, the web index of Korea peaked at the top 10 among the eighty six countries, and Korea became the only Asian country ranked at the top level. Korea also has been on the top in the field of Internet penetration rate, in terms of both high-speed broadband and wireless Internet. However, such achievements did not guarantee the national level for the effective use of information utilizing Internet. According to OECD, the national informatization index of Korea has not been free from the middle of the OECD countries. Despite of the heightened pressure in practically enhancing effective information use utilizing Internet, the previous research interests and efforts to develop the Internet-related framework or to identify Internet capabilities rarely existed. The study aims to propose the framework, named "Internet Information Orientation" that illustrates the relationship between Internet capabilities and national competitiveness on Internet. The research identified the specific Internet capabilities, reclassified the capabilities based on the research issues provided at the 6^th international conference on Internet held in December 2014, and finally described the rigorous research endeavors on the issues. As a result, 16 papers presented and selected as the outstanding papers at the conference handle issues to be brought together, which include: Wireless Network, Internet of Things, Green Computing, Multimedia Processing, Big Data and Text Mining, Database in Cloud Environment, Business Intelligence, Software Engineering, IT Strategy & Policy, and Social Network Services.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.14 no.2
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• pp.159-178
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• 2003

Electronic reference service was defined as reference service designed for remote users and identified by a specific link from a library' website. This study examined whether academic libraries deliver web-based electronic reference services to remote users. Particularly, four types of electronic bulletin board services, free bulletin board, FAQ, Q＆A and reference question-response service were measured in terms of 8 types of questions and 12 contents of questions. The result showed that there was few differences among 4 services. Guidelines for effective use of electronic bulletin board services in academic libraries were suggested: standardization of service names, easy access to menu services, definition of each menu, search function for contents and standard web forms.

• Journal of Information Processing Systems
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• v.5 no.3
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• pp.159-166
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• 2009

As shown in Wikipedia, tagging or cross-linking through major keywords in a document collection improves not only the readability of documents but also responsive and adaptive navigation among related documents. In recent years, the Semantic Web has increased the importance of social tagging as a key feature of the Web 2.0 and, as its crucial phenotype, Tag Cloud has emerged to the public. In this paper we provide an efficient method of automated in-text keyword tagging based on large-scale controlled term collection or keyword dictionary, where the computational complexity of O(mN) - if a pattern matching algorithm is used - can be reduced to O(mlogN) - if an Information Retrieval technique is adopted - while m is the length of target document and N is the total number of candidate terms to be tagged. The result shows that automatic in-text tagging with keywords filtered by Information Retrieval speeds up to about 6 $\sim$ 40 times compared with the fastest pattern matching algorithm.

• Journal of Internet Computing and Services
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• v.19 no.3
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• pp.67-77
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• 2018

This paper suggests that LOD establishes its own link policy and publishes it to LOD cloud to provide identity among entities in different LODs. For specifying the link policy, we proposed vocabulary set founded on RDF model as well. We implemented Policy based In-depth Searching and Cleansing(PISC for short) system that proceeds in-depth searching across LODs by referencing the link policies. PISC has been published on Github. LODs have participated voluntarily to LOD cloud so that degree of the entity identity needs to be evaluated. PISC, therefore, evaluates the identities and cleanses the searched entities to confine them to that exceed user's criterion of entity identity level. As for searching results, PISC provides entity's detailed contents which have been collected from diverse LODs and ontology customized to the content. Simulation of PISC has been performed on DBpedia's 5 LODs. We found that similarity of 0.9 of source and target RDF triples' objects provided appropriate expansion ratio and inclusion ratio of searching result. For sufficient identity of searched entities, 3 or more target LODs are required to be specified in link policy.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.04a
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• pp.427-433
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• 2004

Information is increasing continuously in on-line, it is real condition that inaccurate informations are mass-produced but effort to keep accuracy of these informations is lacking. Already, research about government official of information in World Wide Web is consisting of various method and viewpoint, but problem for the importance of correct information offer and offer of mistake information in World Wide Web about specification target and administration way presentation are no research reward yet and system that can keep accuracy of information is not equiped properly. ss and accuracy whether mistake information in harbor and bay connection web site's administration influences how in authoritativeness security of site and present condition information of harbor and bay and operation information. In this study, we wish to present administration way about mistake informations that is required that recognize problem of mistake information and the administration's importance in on-line in this research, and supply phenomenon information in Web site. We made the right definition about mistake of information through priority literature investigation and virtued research for this, and sorted mistake information in type. And we investigated Pusan port connection information and offered present condition in on-line and research on actual state of mistake information offer and analysis. Reflecting type and special quality of examined mistake informations, We want to make people recognize the importance af freshness and accuracy whether mistake information in harbor and bay connection web site's administration influences how in authoritativeness security of site and present condition information of harbor and bay and operation information.