• Journal of Communications and Networks
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• v.5 no.3
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• pp.215-221
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• 2003

It is expected that per-user customized services are widely used in next generation Personal Communication Network. To provide personalized services for each call, per-user service profiles are frequently referenced and signaling traffic is considerably large. Since the service calls are requested from the places where user stays, we can expect that the traffic is localized. In this paper, we propose a new service profile replication scheme, named Follow-Me Replication with local Anchor (FMRA). By replicating user's service profile in a user-specific location area, local anchor of each region, the signaling traffic for call and mobility can be distributed to local network. We compared the performance of the FMRA with two typical schemes: Intelligent Network-based !Central scheme and IMT-2000 based full replication scheme, as we refer it to Follow-Me Replication Unconditional (FMRU). Performance results indicate that FMRA lies between Central and FMRU schemes according to call to mobility ratio, and we identified the efficient ranges of CMR for FMRA depending on the various network parameters.

• Journal of Communications and Networks
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• v.17 no.2
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• pp.110-117
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• 2015

In mobile social network, it is a critical challenge to select an optimal set of devices to supply high quality service constantly under dynamic network topology and the limit of device capacity in mobile ad-hoc network (MANET). In this paper, a multi-devices composition and maintenance problem is proposed with ubiquitous service model and network model. In addition, a multi-devices composition and maintenance approach with dynamic planning is proposed to deal with this problem, consisting of service discovery, service composition, service monitor and service recover. At last, the simulation is implemented with OPNET and MATLAB and the result shows this mechanism is better applied to support complex ubiquitous service.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.730-731
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• 2011

EPA(Electric Power Automation IT Infra) is a System for Protective Information Transmitter & Receiver and network service. KEPCO(Korea Electric Power Corporation) is building up a high-speed communication network to accept Smart Grid Infra expansion and various terminal communication media characteristic. Recently, MSPP(Multi Service Provisioning Platform) System is establishted to network service. But there are many considerations for optimal design of network service for the Electric Power Automation IT Infra.

• International Journal of Contents
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• v.2 no.2
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• pp.29-31
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• 2006

Mobile Ad hoc network is a self configuring network of mobile nodes. It allows mobile nodes to configure network spontaneously and share their services. In these networks, service discovery is very important because all nodes do not have same resources in term of memory and computing power. Nodes need to use different services offered by different servers. Some service discovery protocols have been proposed in last couple of years but they include significant traffic overhead and for small scale MANETS. In this paper, we present extensible lookup service scheme based on distributed mechanism. In our scheme neighboring nodes of service provider monitor service provider and send notification to lookup server when the service provider terminates its services unexpectedly. Lookup server can find other service provider or other alternative services in advance because of advance notification method and can provide consistent lookup services. In our scheme neighboring nodes also monitor lookup server and send notification to network when lookup server terminates unexpectedly. Simulation results show that our scheme can reduce up to 70% and 30% lookup failure as compare to centralize and simple distributed mechanism respectively.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.3B
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• pp.225-234
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• 2009

Recently IPTV service is penetrating to the ordinary home users very swiftly. One of the first phase of IPTV service is considered to be VoD, and a nationwide availability of the VoD service imposes tremendous pressure to the network resource due to its requirements for the broad bandwidth, the inherent nature of unicast technology, and the large scalability, etc. This work suggests a novel and practical method to the design of network resource for the VoD service. Especially, we explore the distributed content storage problem that takes into account the popularity of the video contents and its corresponding link dimensioning problem that takes into account the grade of service for the flow level quality of service about the VoD service. By assuming a realistic topology for the nationwide IP backbone network of Korea, which is a typical tree topology, we suggest an analytic method for the design of VoD service.

• IEMEK Journal of Embedded Systems and Applications
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• v.2 no.1
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• pp.17-23
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• 2007

The home network has been revitalized due to the emergence of the high-speed broadband network and explosive increases of the home network services. Especially multicast based high-definition (HD) IPTV service is on high demand from both Internet service provider (ISP) and users. In order to provide high quality HD IPTV service without packet loss and delay, the ISP utilizes various network QoS mechanisms. Due to the misleading fact, that the home gateway is considered as an end terminal in terms of the ISP's viewpoint, the ISPs can not guarantee the end-to-end QoS within the scope of the current home network architecture. Therefore, an independent QoS guaranteed mechanism should be considered within the home network domain. As the home gateway manages both private home and public access network within the home network, we propose and implement a novel QoS mechanism for the multicast based HD IPTV service over the home gateway. In order to provide QoS guaranteed HD IPTV service, the proposed mechanism classifies the packets, manages home network bandwidth resources, and executes call admission control using the channel join message. Also, we utilize layer 2 multicast packet forwarding scheme to improve the overall performance of the home network services. Through the experiments of implementing the multicast based HD IPTV services, we will verify the efficiency of the proposed mechanism.

• Korean Journal of Child Studies
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• v.34 no.6
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• pp.159-175
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• 2013

The purpose of this study was to explore how the number of network organizations, network continuity and service continuity of community child centers were affected by the charge factors, organizational factors and environmental factors of community child centers. To better understand this, we researched 107 community child centers in Chonbuk Province. The key results are as follows. The interpersonal connections of the charge factors had a strong effect on the number of network organizations, but organizational factors and environmental factors appeared to have no effect on the number of network organizations. The operational type(religious group), organizational support level of the organizational factors and public-private cooperation, regular consultative group operation(no) of the environmental factors appeared to have an effect on the level of network continuity. The region(local), regular consultative group operation(yes) and public-private cooperation of the environmental factors appeared to have an effect on the level of service continuity. It was hoped that the results would enable us to explore how factors related to a network had an effect on the service continuity, the number of network organizations and clients referral network continuity, and they appeared to have an effect on the service continuity.

• The Journal of Industrial Distribution & Business
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• v.8 no.7
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• pp.21-29
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• 2017

Purpose - The purpose of this study is to investigate the impact of organizational politics on employees' social network service addiction and how it influences their job satisfaction and organizational citizenship behavior. And this study explores if leader-member exchange can moderate the relationship between organizational politics and social network service addiction. Research, design, data, and methodology - For this, this study collected data from 305 employees in Korean companies through a survey method and uses SPSS 18.0 for hierarchical regression analysis in the hypothesis test. Results - First, organizational politics increases immersion, compulsion and association among the sub-factors of social network service addiction. Second, each phenomena of social network service addiction such as salience, compulsion and association decrease each relevant factors of job satisfaction and organizational citizen behavior. Third, compulsion and association among the sub-factors of social network service addiction play the mediating roles between organizational politics and each relevant factors of job satisfaction/organizational citizen behavior. Finally, some of sub-factors of leader-member exchange decrease the effect of each characteristics of organizational politics on immersion, compulsion and association among the sub-factors of social network service addiction. Conclusions - This study provides some of managerial implications to corporate executives who try to manage organizational attitude.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.1586-1589
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• 2005

GUMF (Global User Management Framework) that is proposed in this research can be applied to next generation network such as BcN (Broadband convergence Network), it is QoS guaranteed security framework for user that can solve present Internet's security vulnerability. GUMF offers anonymity for user of service and use the user's real-name or ID for management of service and it is technology that can realize secure QoS. GUMF needs management framework, UMS (User Management System), VNC (Virtual Network Controller) etc. UMS consists of root UMS in country dimension and Local UMS in each site dimension. VNC is network security equipment including VPN, QoS and security functions etc., and it achieves the QoSS (Quality of Security Service) and CLS(Communication Level Switching) functions. GUMF can offer safety in bandwidth consumption attacks such as worm propagation and DoS/DDoS, IP spoofing attack, and current most attack such as abusing of private information because it can offer the different QoS guaranteed network according to user's grades. User's grades are divided by 4 levels from Level 0 to Level 3, and user's security service level is decided according to level of the private information. Level 3 users that offer bio-information can receive secure network service that privacy is guaranteed. Therefore, GUMF that is proposed in this research can offer profit model to ISP and NSP, and can be utilized by strategy for secure u-Korea realization.

• Journal of the Korea Society for Simulation
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• v.14 no.2
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• pp.83-92
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• 2005

Access networks connected in B3G networks provide its property network service. Hence, though mobile users may utilize only a network service from an access network, they can also use variety of network services from several access networks for their service satisfaction. To support heterogeneous changeable network service in access networks, the mobile terminal must implement heterogeneous system techniques so that it is able to change the network service by ISHO (Inter-System Handover) In this paper, we present the ISHO condition by the policy-based framework in B3G networks. Also, we propose an ISHO scheme to control network resources for the QoS management of a mobile session between UMTS and WLAN access networks. To support the QoS management, the proposed scheme is that it will be implemented before the resource exhaustion occurs to effect network performances.