• KIPS Transactions on Computer and Communication Systems
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• v.8 no.8
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• pp.191-200
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• 2019

In an Ad-hoc network, a method of time synchronizing all the nodes in a network centering on one reference node can be used. A representative algorithm based on a reference node is Flooding Time Synchronization Protocol (FTSP). In the process of sending and receiving messages, predictable and unpredictable delays occur, which should be removed because it hinders accurate time synchronization. In multi-hop communications, hop delays occur when a packet traverses a number of hops. These hop delays significantly degrade the synchronization performance among nodes. Therefore, we need to find a method to reduce these hop delays and increase synchronization performance. In the FTSP scheme, hop delays can be greatly increased depending on the position of a reference node. In addition, in FTSP, a node with the smallest node ID is elected as a reference node, hence, the position of a reference node is actually arbitrarily determined. In this paper, we propose an optimal reference node election algorithm to reduce hop delays, and compare the performance of the proposed scheme with FTSP using the network simulator OPNET. In addition, we verify that the proposed scheme has an improved synchronization performance, which is robust to topology changes.

• Korea Science and Art Forum
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• v.20
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• pp.455-464
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• 2015

As the recognition toward the Korean design education development to nurture creative talents for the future society has been expanded recently, various supports and promoting strategies are being suggested. This study suggests the orientalism-based new design education platform in design education field to nurture creative talents. To have the competitiveness of creative talent nurturing, the system and education programs to rear creative talents are required. The purpose of this study is to suggest the new platform for the change of direction in design education and search for the methods in detail. The research process can be described as following: First, this study stated about the research background and its boundary. Based on the literature review and the condition of the crisis of Korean design education (Korean Industrial Statistic Investigation), it described the current condition and the characteristics. Second, this study stated about the education which will be disappeared in the information society, the change of direction in design education, and the new platform. In the current study, the change toward the strategies that give priority to the growth strategies on the knowledge-based industry was stated. Third, this study stated about that the future design education should be centered on the orientalism-based creativity in the trend changing to the six conditions for the future talents and the beliefs and values toward Asia, and what methods should be sought to achieve this trend. It suggested focusing on the aim for the direction for College education and its program curriculums as the solutions in detail. Fourth, based on the contents stated earlier in this study, it stated synthetically the direction of practice through the network of the design cluster and derived the implications. In conclusion, based on the recent orientalism-based mind, this study suggested the ways to find the identity of Korean design education itself and have the competitiveness in design education programs. The ways to secure them is to come from the integrated system innovation of the network. By actively applying the design clusters, colleges and universities, designers, studios, government policy organizations, design institutes, corporates, media, and fairs, this study suggests the sustainable education system and the practical methods.

• Journal of KIISE:Information Networking
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• v.32 no.1
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• pp.68-79
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• 2005

The popularity of Web service is ever increasing. As the number of services and clients continue to increase, the problem of providing a system that scales with this increase is becoming more difficult. A costly and ineffective method is to buy a new system that is more powerful every time the load becomes unbearable. h more cost effective solution is to expand the system as the need arises. This is the approach taken in Web cluster systems. However, providing effective scalability in a Web cluster system is stil1 an open issue. In this study, we implement a Web cluster system based on Layer 7 switching technique on Linux. The implementation is based on a design proposed and implemented by Aron et al., but on the FreeBSD. Though the design li the same, due to the vast difference between the FreeBSD and Linux, the implementation presented in this paper is totally new. We also propose the Dual Scheduling (DS) load distribution algorithm that distributes the requests to the system resources by observing the variations in the request rate. We show through measurement on our implementation that the DS alorithm performs considerably bettor than previous algorithms.

• Smart Media Journal
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• v.7 no.4
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• pp.30-36
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• 2018

Single domain model like DataLake framework is in spotlight because it can improve data efficiency and process data smarter in big data environment, where large scaled business system generates huge amount of data. In particular, efficient operation of network, storage, and computing resources in logical single domain model is very important for physically partitioned multi-site data process. Based on the advantages of Data Lake framework, we define and extend the concept of Connected Data Architecture and functions of DataLake framework for integrating multiple sites in various domains and managing the lifecycle of data. Also, we propose the design of CDA-based AI service and utilization scenarios in various application domain.

• The Journal of the Korea Contents Association
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• v.14 no.11
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• pp.467-475
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• 2014

With the development of genomics, wearable device and IT/NT, a vast amount of bio-medical data are generated recently. Also, healthcare industries based on big-data are booming and big-data technology based on bio-medical data is rising rapidly as a core technology for improving the national health and aged society. A pathway is the biological deep knowledge that represents the relations of dynamics and interaction among proteins, genes and cells by a network. A pathway is wildly being used as an important part of a bio-medical big-data analysis. However, a pathway analysis requires a lot of time and effort because a pathway is very diverse and high volume. Also, multidimensional analysis systems for various pathways are nonexistent even now. In this paper, we proposed a pathway analysis system that collects user interest pathways from KEGG pathway database that supports the most widely used pathways, constructs a network based on a hierarchy structure of pathways and analyzes the relations of dynamics and interaction among pathways by clustering and selecting core pathways from the network. Finally, to verify the superiority of our pathway analysis system, we evaluate the performance of our system in various experiments.

• Korean Journal of Social Welfare
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• v.68 no.1
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• pp.73-94
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• 2016

The purpose of this study is to examine the trend of the studies on Korean social welfare administration over a recent 10 year period. Employing both network analysis and content analysis, which are representative statistical strategies to identify research trends, we analyzed 221 articles published in the Journal of Korean Social Welfare Administration from 2005 to 2014. The major findings were as follows; First, we found two clusters -"social (welfare) service" and "social welfare organization"- in the studies of social welfare administration. In addition, more than 80% of articles are mainly related with human resource management, including job satisfaction, organizational commitment, and so forth. Second, the newly emerging academic subjects such as social enterprise and community network appeared to be done independently of traditional subjects. Third, the proportion of quantitative studies being focused on human resources was overwhelmingly high compared to the other types of studies; therefore, there are a few studies using qualitative or mixed method, evidence based practice, and discourse studies. In addition, the studies of the rural areas, which are a blind spot of the social service delivery system, and the studies about information management, financial management, marketing, organization innovation rarely appeared, despite their significance.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.3
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• pp.442-458
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• 2008

This paper aims to examine the ways in which project-based organizations (PBOs) are embedded in social networks and geographical clustering in the case of TV drama industry. PBOs refer to a variety of temporary organizational forms for the performance of tasks as to integrate diverse and specialized intellectual resources. PEOs as a flexible and innovative mode of organizing knowledge resources are becoming increasingly worthy of attention in emerging the creative economy. Evidence from interviews with core persons of PEOs like producers, directors, and writers reveals that the key operational mechanism of the project form of organization is based on the highly socialized networks via individual's reputation and past experiences. In other words, the project activity in TV drama is embedded in networks which are socially constructed. Also the geographical clustering plays an important role in PBOs and project practices in TV drama are constructed around a high degree of spatial clustering. PBOs are clustering in Kang-nam and Yeouido, where are located in independent production companies and broadcasting stations. It means that the project formation in TV drama requires geographically-clustered networks of human resources, and socially, culturally and geographically embedded latent networks of interpersonal relationships are a necessary condition of POBs in the TV drama industry.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.278-280
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• 2012

We are propose the position of the node context-awareness information and the validity of the head node in the path according to the clustering how to elect one of the energy efficiency ECOPS (Energy Conserving Optimal path Schedule) algorithm. Existing LEACH algorithm to elect the head node when the node's energy probability distribution function based on the management of the head node is optional cycle. However, in this case, the distance of the relay node status information including context-awareness parameters does not reflect. These factors are not suitable for the relay node or nodes are included in the probability distribution, if the head node selects occurs. In particular, to solve the problems from the LEACH-based hierarchical clustering algorithms, this study defines location with the status context information and the residual energy factor in choosing topology of the structure adjacent nodes. ECOPS algorithm that contextual information is contributed for head node selection in topology protocols. The proposed ECOPS algorithm has the head node replacement situations from the candidate head node in the optimal path and efficient energy conservation that is the path of the member nodes. The new head node election show as the entire node lifetime and network management technique improving the network lifetime and efficient management the simulation results.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.6
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• pp.187-193
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• 2015

The ICT healing platform sets a couple of goals including preventing chronic diseases and sending out early disease warnings based on personal information such as bio-signals and life habits. The 2-step open system(TOS) had a relay designed between the healing platform and the storage of personal health data. It also took into account a publish/subscribe(pub/sub) service based on large-scale connections to transmit(monitor) the data processing process in real time. In the early design of TOS pub/sub, however, the same buffers were allocated regardless of connection idling and type of message in order to encode connection messages into a deflate algorithm. Proposed in this study, the dynamic buffer allocation was performed as follows: the message transmission type of each connection was first put to queuing; each queue was extracted for its feature, computed, and converted into vector through tf-idf, then being entered into a k-means cluster and forming a cluster; connections categorized under a certain cluster would re-allocate the resources according to the resource table of the cluster; the centroid of each cluster would select a queuing pattern to represent the cluster in advance and present it as a resource reference table(encoding efficiency by the buffer sizes); and the proposed design would perform trade-off between the calculation resources and the network bandwidth for cluster and feature calculations to efficiently allocate the encoding buffer resources of TOS to the network connections, thus contributing to the increased tps(number of real-time data processing and monitoring connections per unit hour) of TOS.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11c
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• pp.2383-2386
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• 2002

많은 ISP업체와 서버 관리자들은 자신의 시스템 향상을 위하여 많을 비용을 쏟아 붇고 있지만 그 결과는 비관적이다. 지금까지는 하드웨어적인 성능만을 고려하였으나, 최근에는 리눅스를 탑재하여 낮은 가격과 높은 가용성을 가지면서, 증가하는 네트워크 요청에 효과적으로 대응하기 위한 해결책으로 여러 대의 호스트로 구성되는 클러스터링 기술이 각광을 받고 있다. 또한 클러스터는 저렴한 호스트들로 구성되므로 구축 비용이 절감되는것 뿐만 아니라, 일부 호스트가 고장 나더라도 다른 호스트는 네트워크 작업 분담을 재설정하여 정상적으로 동작함으로 가용성이 항상 유지될 수 있다는 것을 보여준다. 최근 군에서도 정보화 과학화의 열풍에 힘입어 그 어느때보다도 업무의 전산화, 정보화에 박차를 가하고 있는 실정이다. 이로 인한 군업무에 적용되는 중대형 서버의 증가와 1인 1PC정책에 의한 클라이언트의 증가, 네트웍 인프라 구축에 심혈을 기울이고 있다. 그러나 사용자의 요구만큼 군환 경하에서의 정보화 업무를 감당하는 서버의 역량은 제한이 있다. 군업무의 특수성에 비추어 볼때에도 사회의 금융업무와 마찬가지로 중단없는 서비스의 수행과 서버의 안정화는 군전산의 가장 중요한 요소중의 하나임에 불구하고 아직까지도 현실성은 많이 미비한 상태이다. 본 연구는 이와 같은 문제를 해결하기 위하여 NAS와 SAN개념(네트웍기반)을 도입하여 군 서버 구축 새로운 패러다임을 제공하여 업무의 통폐합과 함께 서버의 통폐합의 전초단계인 무정지 클러스터링 서버의 구축방안을 제시하여 군정보화, 과학화의 초석을 다지는 계기로 삼고자 한다.위상변화에 대한 적응성을 높일 수 있도록 한다. SQL Server 2000 그리고 LSF를 이용하였다. 그리고 구현 환경과 구성요소에 대한 수행 화면을 보였다.ool)을 사용하더라도 단순 다중 쓰레드 모델보다 더 많은 수의 클라이언트를 수용할 수 있는 장점이 있다. 이러한 결과를 바탕으로 본 연구팀에서 수행중인 MoIM-Messge서버의 네트워크 모듈로 다중 쓰레드 소켓폴링 모델을 적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임