• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.7B
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• pp.710-720
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• 2009

The Future Generation Networks(FGNs) are proposed to integrate various heterogeneous access technologies, and further expected to support both vertical and seamless handovers. In this motivation, the IEEE 802.21 specifies Media Independent Handover(Mlli) services to enhance the mobile user experience by optimizing handovers between heterogeneous access networks. Additionally, Fast handover for MIPv6(FM1Pv6) is introduced to provide transparent host mobility and to improve handover performance by reducing handover delay as well. This paper focuses on the coordination of FMIPv6 and MIH, and introduces an enhanced mobility management framework suited for FGN. This novel framework replaces handover signaling messages used in wireless networks with novel MIH messages and local primitives. Moreover, Serving Access Router(SAR) performs most of handover processes instead of Mobile Node(MN). Therefore, the proposed mobility management framework reduces handover latency, packet loss, and signaling overhead significantly. We further evaluate the performance of the proposed framework by using both numerical analysis and network simulations.

• Journal of Soil and Groundwater Environment
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• v.21 no.1
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• pp.104-110
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• 2016

The transport of silver nanoparticles (AgNPs) was investigated through a column packed with sand. A series of column experiments were carried out to evaluate the effect of ionic strength (IS), pH, electrolyte type and clay mineral on mobility of polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNPs). The deposition of PVP-AgNPs was increased with increasing solution ionic strength and decreasing pH. Furthermore, the depositon of PVP-AgNPs was affected by the electrolyte type (NaCl vs. NaNO₃) and was shown to be greater at NaNO₃ solution. Also, the transport of PVP-AgNPs was greatly increased after the pre-deposition of clay particles on sand. Our results suggest that various environmental factors can influence the mobility of PVP-AgNPs in soil-groundwater systems and should be carefully considered in assessing their environmental risks.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1435-1439
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• 2004

Most recently, CP(Cellular Phone) has been one of the most important technologies in the IT(Information Tech-nology) field, and it is situated in a position of great importance industrially and economically. To produce the best CP in the world, a new technological concept and its advanced implementation technique is required, due to the extreme level of competition in the world market. The RT(Robot Technology) has been developed as the next generation of a future technology. Current robots require advanced technology, such as soft computing, human-friendly interface, interaction technique, speech recognition, object recognition etc. unlike the industrial robots of the past. Therefore, this paper explains conceptual research for development of the RCP(Robotic Cellular Phone), a new technological concept, in which a synergy effect is generated by the merging of IT & RT. RCP infra consists of $RCP^{Mobility}$ $RCP^{Interaction}$, $RCP^{Integration}$ technologies. For $RCP^{Mobility}$, human-friendly motion automation and personal service with walking and arming ability are developed. $RCP^{Interaction}$ ability is achieved by modeling an emotion-generating engine and $RCP^{Integration}$ that recognizes environmental and self conditions is developed. By joining intelligent algorithms and CP communication network with the three base modules, a RCP system is constructed. Especially, the RCP mobility system is focused in this paper. $RCP^{Mobility}$ is to apply a mobility technology, which is popular robot technology, to CP and combine human-friendly motion and navigation function to CP. It develops a new technological application system of auto-charging and real-world entertainment function etc. This technology can make a CP companion pet robot. It is an automation of human-friendly motions such as opening and closing of CPs, rotation of antenna, manipulation and wheel-walking. It's target is the implementation of wheel and manipulator functions that can give service to humans with human-friendly motion. So, this paper presents the definition, the basic theory and experiment results of the RCP mobility system. We confirm a good performance of the RCP mobility system through the experiment results.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37B no.12
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• pp.1119-1127
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• 2012

The one of features of M2M communications, which are recently attracted attention as a future business of mobile communications, is that there is a large number of devices compared with traditional communication services. Hence, the control signal that are generated by the M2M devices may cause a significant congestion in the network and in order to solve this problem, a standardization is progressing for reducing the redundant signaling by managing M2M devices as a group in 3GPP standardization. In this paper, we propose a method of group based mobility management by managing M2M devices that have the same mobility as a group. In the proposed method, M2M devices that have the same mobility are grouped by the Mobility Management Entity (MME) and the MME elects a group header among the M2M devices in the group. Then, the group header performs the Tracking Area Update (TAU) on behalf of the group members to reduce the signaling overhead of mobility management. With the proposed method, we can achieve 80% decrease of the signaling overhead of mobility management compared with the case where each M2M device individually performs its TAU procedure.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.163-166
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• 2003

In recent years, there has been increased to access multimedia service through the Internet due to rise of the access speed. We suppose the co-existence of the various access networks in adjacent area in the future, such as wireless LAN, Bluetooth, and 3G Cellular So, the size of the cell will be smaller and the number of access point will be increased. In other words, the potable devices need the efficient mobility scheme due to move between cells frequently Currently, the several of the scheme, which is Cellular IP, HAWAII, Mobile IPv4 regional registration, and hierarchical Mobile IPv6, is suggested to support micro-mobility but Mobile IPv4 is standard scheme to support the mobility of the mobile node. MPLS, which forwards the packet through switching instead of routing using IP address, has begun to deploy in the internet backbone to increase the performance of mobility protocol. The integration of both MPLS and Mobile IP improves the scalability of the Mobile IP data forwarding process by leveraging on the features MPLS which are fast switching and high scalability. Moreover it abbreviates IP-in-IP tunneling between HA and FA. In this paper, we suggest efficient mobility scheme through integration of both MPLS and hierarchical Mobile IPv6.

• Journal of the Korean Society of Safety
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• v.39 no.1
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• pp.62-69
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• 2024

Ensuring swift on-site access to fire engines is crucial in preserving the golden time and minimizing damage. However, various mobility constraints in alleyways hinder the timely entry of fire engines to the fire scene, significantly impairing their initial response capabilities. Therefore, this study analyzed the significant mobility constraints of fire engines, focusing on Seoul, which has many old town areas. By leveraging survey responses from firefighting experts and actual observations, this study quantitatively assessed the frequency and severity of mobility constraint factors affecting the disaster responses of fire engines. Survey results revealed a consistent set of top five factors regarding the frequency and disturbance level, including illegally parked cars, narrow paths, motorcycles, poles, and awnings/banners. A comparison with actual road-view images showed notable consistency between the survey and observational results regarding the appearance frequency of mobility constraint factors in vulnerable areas in Seoul. Furthermore, the study emphasized the importance of tailored management strategies for each mobility constraint factor, considering its characteristics, such as dynamic or static. The findings of this study can serve as foundational data for creating more detailed fire safety maps and advancing technologies that monitor the mobility of fire engines through efficient vision-based inference using CCTVs in the future.

• Fashion & Textile Research Journal
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• v.9 no.1
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• pp.6-14
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• 2007

The purpose of this study was to delve into what type of expression mode of fashion design could suit the life style of digital nomads, as the appearance of nomadic life style was concurrent with people's modified way of thinking and sociocultural changes in today's digital society. It's basically meant to define the roles of fashion design, which was discussed as a way of improving the quality of life as a sort of 'culture,' and to suggest some of the right directions for fashion design in the future. The culture of today's digital era is marked by a pursuit of high mobility and high speed, and by nomadic disposition that is built on flexible thinking. The kind of design that lets people carry nomadic things with them and thereby improve their mobility can satisfy their needs for mobility, and body-friendly design that functions as a device of information in itself can meet their needs for mobility as well. The leading example of the latter is a wearable computer, and wearable scientific technology will be taken to another level, thanks to the advance in digital technology. In the future, that will be more accessible to people in general, and subminiature digital equipment will gain popularity in fashion industry as part of textiles and clothing or as an accessory. And specific kinds of design will be widespread, including variable design, multi-functional design and modular design. The first serves as a tool to protect the human body and to facilitate the adaptability of it to the given circumstances, and the second is characterized by a superb physical and psychological protectability. The third lets wearers bring design to completion at their own option, owing to an increase in the number of open-minded people and the development of interactive media. All these types of design could be called a wearer-friendly, human-oriented design that is specifically appropriate for the digital age. Wearers can actively be involved in design process as productive consumers, which is expected to help increase opener practices in fashion design sector.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.9
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• pp.2118-2135
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• 2012

With the rapid development of heterogeneous emerging wireless technologies and numerous types of mobile devices, the need to support robust mobile video streaming based on the seamless handover in Future Internet is growing. To support the seamless handover, several IP-based mobility management protocols such as Mobile IPv6 (MIPv6), fast handover for the MIPv6 (FMIPv6), Hierarchical MIPv6 (HMIPv6) and Proxy Mobile IPv6 (PMIPv6) were developed. However, MIPv6 depreciates the Quality-of-Service (QoS) and FMIPv6 is not robust for the video services in heterogeneous emerging wireless networks when the Mobile Node (MN) may move to another visited network in contrast with its anticipation. In Future Internet, the possibility of mobile video service failure is more increased because mobile users consisting of multiple wireless network interfaces (WNICs) can frequently change the access networks according to their mobility in heterogeneous wireless access networks such as 3Generation (3G), Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMax) and Bluetooth co-existed. And in this environment, seamless mobility is coupled according to user preferences, enabling mobile users to be "Always Best Connected" (ABC) so that Quality of Experience is optimised and maintained. Even though HMIPv6 and PMIPv6 are proposed for the location management, handover latency enhancement, they still have limit of local mobility region. In this paper, we propose a robust mobile video streaming in Heterogeneous Emerging Wireless Systems. In the proposed scheme, the MN selects the best-according to an appropriate metric-wireless technology for a robust video streaming service among all wireless technologies by reducing the handover latency and initiation time when handover may fail. Through performance evaluation, we show that our scheme provides more robust mechanism than other schemes.

• KIEAE Journal
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• v.10 no.5
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• pp.101-108
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• 2010

It is estimated that the elderly will constitute 24.3% of the entire Korean population in 2030, when about 7,125,000 baby boomers reach retirement age. Therefore, this aging phenomenon might be the most urgent issue facing Korean society. The baby boom generation shows a strong tendency to dispose of existing residences or move into new housing after retirement, thereby exerting enormous impacts on social and economic sectors as well as the housing market. Against this backdrop, this study aims to identify both factors and patterns behind baby boomer retirees' post-retirement housing transfer trends. To this end, a survey is undertaken here with respect to those baby boomers living in Gangnam-gu and Seocho-gu with actual housing transfer plans in the foreseeable future, and who can act as a practical consumer group for the future housing market. This study verifies baby boomers' diverse preferences for housing type. Their preference for apartment houses still remains high in every situation, and this has significant implications for changed preferences of other housing types considering that most of the survey respondents currently reside in apartment houses. According to the survey, there are more than 80 kinds of baby boomers' housing transfer patterns, which demonstrates that more than half of the survey respondents pursue different housing mobility plans. When it comes to the factors behind their housing selection, the baby boom generation shows a strong preference for physical factors. However, environmental and psychological factors gain more momentum under unfavorable circumstances, while social factors play a decisive role in their housing selection in categories such as 'couple/deteriorating health' and 'single/healthy'.

• Journal of Advanced Navigation Technology
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• v.26 no.3
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• pp.125-135
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• 2022

UAM is emerging as the biggest issue in the aviation industry and which is attracting a lot of attention not only domestically but also internationally. In Korea, active research is being conducted centered on the government and industry-university research institutes, such as the establishment of a future K-UAM concept of operation. Therefore, in this study applies the SORA (Specific Operation Risk Assessment) model established by the European JARUS (Joint Authorities for Rulemaking on Unmanned Systems) to apply the K-UAM operation environment and specific corridor for the purpose of cargo transportation that will be operated in the future that the government is promoting. We intend to suggest policy and technical measures for risk mitigation in the initial operating environment by evaluating the level of risk and analyzing the results.