• The Korean Journal of Physiology and Pharmacology
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• 제16권3호
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• pp.199-204
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• 2012

We evaluated the role of Tat-mediated p66shc transduction on the activation of endothelial nitric oxide synthase in cultured mouse endothelial cells. To construct the Tat-p66shc fusion protein, human full length p66shc cDNA was fused with the Tat-protein transduction domain. Transduction of TAT-p66shc showed a concentration- and time-dependent manner in endothelial cells. Tat-mediated p66shc transduction showed increased hydrogen peroxide and superoxide production, compared with Tat-p66shc (S/A), serine 36 residue mutant of p66shc. Tat-mediated p66shc transduction decreased endothelial nitric oxide synthase phosphorylation in endothelial cells. Furthermore, Tat-mediated p66shc transduction augmented TNF-${\alpha}$-induced p38 MAPK phosphorylation in endothelial cells. These results suggest that Tat-mediated p66shc transduction efficiently inhibited endothelial nitric oxide synthase phosphorylation in endothelial cells.

• 융합보안논문지
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• 제17권5호
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• pp.57-61
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• 2017

국가 연구망(National Research Network)은 각국의 첨단과학기술을 지원하기 위해 존재한다. 국가 연구망은 각 분야의 과학기술에 대한 요구사항을 충족하여야 하며, 지속적으로 변해가는 주변 환경에 대해서 끊임없이 발전해 나가야 한다. 최근 데이터 중심의 과학기술 연구형태에 따른 수요가 증가하고 있으며, 이러한 수요에 대응하기 위해 선진 국가 연구망들은 중장기적인 전략을 수립하고 있다. 본 논문에서는 선진 연구망에 대한 현황과 국가 연구망 동향 및 요구사항을 연구망환경의 변화, 과학/기술의 변화, 산업과 삶의 변화의 관점에서 분석하였다. 또한 분석한 요구사항에 대응하기 위해 미래형 네트워크 백본 구축, 사용자 중심의 협업 연구 환경 제공, 글로벌 협업 네트워크 서비스 제공, 첨단과학기술 연구데이터 정보 보호 서비스 제공 등에 관해 중장기 발전 방향 및 방안을 제시한다.

• Journal of Ginseng Research
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• 제32권3호
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• pp.244-249
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• 2008

Vascular inflammation is an important step in the development of cardiovascular disorder. Since it has not been known whether Korean red ginseng has a role to play on the vascular inflammation, we investigated the effects of Korean red ginseng extract (KRGE) on monocyte adhesion and its underlying signaling mechanism. Monocyte adhesion assay and Western blot were conducted on the human umbilical vein endothelial cells to study monocyte adhesion and the expression of adhesion molecules. Intracellular calcium was measured with Fura-2 fluorescent staining, and superoxide production was measured with lucigenin chemiluminescence in the endothelial cells. KRGE inhibits tumor necrosis factor (TNF)-alpha-induced monocyte adhesion on the endothelial cells at the range of $0.03{\sim}1$ mg/ml. TNF-alpha-induced vascular cell adhesion molecule-1 and intercellular cell adhesion molecule-1 expression were inhibited by the pretreatment of KRGE in the endothelial cells. KRGE also inhibits TNF-alpha-induced intracellular calcium and the superoxide production in the endothelial cells. This study first demonstrated that KRGE inhibits TNF-alpha-induced monocyte adhesion by inhibiting the adhesion molecule expression, intracellular calcium and superoxide production in the endothelial cells. Therefore, the anti-inflammatory function of KRGE may be contributed to protecting the endothelial dysfunction in the vascular inflammatory disorders.

• 한국멀티미디어학회논문지
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• 제22권4호
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• pp.502-514
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• 2019

Existing user research methods are subject to a variety of research conditions such as the amount and variety of data collected and the expertise of the facilitator of a group research session. In this study, we propose a new user research methodology using an 'Issue-Network' system, which is developed based on the theory and methods of social network analysis. The Issue-Network is designed to define problem spaces from the issues raised by users in a group research session in a form of an interactive network graph. The system helps to break out of ordinary perspectives of looking into problem spaces by enabling an alternative and more creative way to connect issues in the network. In this study, we took a case study of generating the Issue-Network on behalf of the problems raised by users in various driving-related situations. We were able to draw three navigation usage scenarios that cover relatively important problem spaces: safety and being ready for the unexpected, smart navigation and notifications, making use of the spare time. In the future, the Issue-Network system is expected to be used as a tool to identify problems and derive solutions in group research sessions involving a large number of users.

• ETRI Journal
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• 제39권4호
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• pp.525-534
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• 2017

A hardware-acceleration architecture that separates virtual network functions (VNFs) and network control (called HSN) is proposed to solve the mismatch between the simple flow steering requirements and strong packet processing abilities of software-defined networking (SDN) forwarding elements (FEs) in SDN/network function virtualization (NFV) architecture, while improving the efficiency of NFV infrastructure and the performance of network-intensive functions. HSN makes full use of FEs and accelerates VNFs through two mechanisms: (1) separation of traffic steering and packet processing in the FEs; (2) separation of SDN and NFV control in the FEs. Our HSN prototype, built on NetFPGA-10G, demonstrates that the processing performance can be greatly improved with only a small modification of the traditional SDN/NFV architecture.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권8호
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• pp.3701-3727
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• 2016

Recently Service Function Chaining (SFC) is promising to innovate the network service mode in modern networks. However, a feasible implementation of SFC is still difficult due to the need to achieve functional equivalence with traditional modes without sacrificing performance or increasing network complexity. In this paper, we present a configurable network service chaining (CNSC) mechanism to provide services for network traffics in a flexible and optimal way. Firstly, we formulate the problem of network service chaining and design an effective service chain construction framework based on integrating software-defined networking (SDN) with network functions virtualization (NFV). Then, we model the service path computation problem as an integer liner optimization problem and propose an algorithm named SPCM to cooperatively combine service function instances with a network utility maximum policy. In the procedure of SPCM, we achieve the service node mapping by defining a service capacity matrix for substrate nodes, and work out the optimal link mapping policies with segment routing. Finally, the simulation results indicate that the average request acceptance ratio and resources utilization ratio can reach above 85% and 75% by our SPCM algorithm, respectively. Upon the prototype system, it is demonstrated that CNSC outperforms other approaches and can provide flexible and scalable network services.

• 수산해양교육연구
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• 제29권1호
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• pp.224-233
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• 2017

This study aims to analyze the research trend of lifelong education in Korea over the last 10 years based on social network analysis. To do this, a dataset has been collected from KCI (Korea Citation Index) database. According to the results of the study, firstly, the current status of lifelong education research by the year in the last 10 years showed a relatively high ratio between 2008 and 2009 and 2014 ~ 2015. Secondly, the most active networks between authors and journals constitute a key group in the order of 'Lifelong Education Study' and 'Lifelong Learning Society'. Thirdly, the research institutes with the largest number of lifelong education research papers are Soongsil University, Dong-Eui University, and Korea National Open University. In the network with the authors' network, the only authors were K8 working at Chonbuk National University, and the co-authors, H4, who works at Kyungpook National University, showed the most active network. Finally, the core keyword network based on the thesis topic was analyzed as having higher connection centrality in the order of 'lifelong education', 'lifelong educator', and 'university lifelong education'.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2008년도 International Meeting of the Microbiological Society of Korea
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• pp.31-32
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• 2008

• 융합보안논문지
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• 제16권7호
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• pp.3-11
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• 2016

최근 광네트워킹 기술의 급격한 발전, SDN (Software-Defined Network) 및 NFV (Network Function Virtualization)로 대두되는 네트워크의 소프트웨어화, 그리고 단순한 고성능연결서비스를 포함한 연구협업을 가능하게 하는 플랫폼으로써의 연구망 등 인터넷 서비스을 포함한 연구망에서는 급격한 변화가 진행되고 있다. 이에 슈퍼컴과 함께 국가과학기술경쟁력을 대표하는 국가연구망의 향후 발전방향을 선진 국가연구망의 비교분석 및 사회가 요구하는 연구망의 역할 변화에 맞추어 조망해본다. 또한 국가연구망 백본의 40Gbps 및 100Gbps급 초광대역 네트워크화, 대용량의 데이터를 고속으로 전송하기 위한 Science DMZ 기반의 망분리, 마지막으로 BRO 기반 프로그래머블 가능한 캠퍼스 네트워크 Lastmile 보안 환경 구축 방안을 제시한다.

• Journal of Information Science Theory and Practice
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• 제10권spc호
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• pp.12-24
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• 2022

This study attempted to investigate changes in collaboration structure for each stage of national Research and Development (R&D) in the artificial intelligence (AI) field through analysis of a co-author network for papers written under national R&D projects. For this, author information was extracted from national R&D outcomes in AI from 2014 to 2019. For such R&D outcomes, NTIS (National Science & Technology Information Service) information from the KISTI (Korea Institute of Science and Technology Information) was utilized. In research collaboration in AI, power function structure, in which research efforts are led by some influential researchers, is found. In other words, less than 30 percent is linked to the largest cluster, and a segmented network pattern in which small groups are primarily developed is observed. This means a large research group with high connectivity and a small group are connected with each other, and a sporadic link is found. However, the largest cluster grew larger and denser over time, which means that as research became more intensified, new researchers joined a mainstream network, expanding a scope of collaboration. Such research intensification has expanded the scale of a collaborative researcher group and increased the number of large studies. Instead of maintaining conventional collaborative relationships, in addition, the number of new researchers has risen, forming new relationships over time.