• Journal of IKEEE
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• v.13 no.4
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• pp.15-21
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• 2009

Proxy Mobile IP in IETF is a network-based mobility management scheme to solve the problem of host-based mobility management scheme, Mobile IP. PMIP shows the better performance in the aspect of mobility, but PMIP, as a legacy of Mobile IP based on "best effort service", lacks of consideration of QoS. In this thesis, a novel mobility support scheme is proposed for mobility and QoS support based on PMIP in MPLS networks.

• Journal of Computing Science and Engineering
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• v.9 no.3
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• pp.155-162
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• 2015

The last decade has seen a rapid growth in the use of mobile devices all over the world. With an increasing use of mobile devices, mobile applications are becoming more diverse and complex, demanding more computational resources. However, mobile devices are typically resource-limited (i.e., a slower-speed CPU, a smaller memory) due to a variety of reasons. Mobile users will be capable of running applications with heavy computation if they can offload some of their computations to other places, such as a desktop or server machines. However, mobile users are typically subject to dynamically changing network environments, particularly, due to user mobility. This makes it hard to choose good offloading decisions in mobile environments. In general, users' mobility can provide some hints for upcoming changes to network environments. Motivated by this, we propose a mobility model of each individual user taking advantage of the regularity of his/her mobility pattern, and develop an offloading decision-making technique based on the mobility model. We evaluate our technique through trace-based simulation with real log data traces from 14 Android users. Our evaluation results show that the proposed technique can help boost the performance of mobile devices in terms of response time and energy consumption, when users are highly mobile.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.8
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• pp.3060-3069
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• 2010

LBS is service technique to provide several service which are required to user by user's location information for mobile. This paper presents Auto_Test system of testing the mobility performance of mobile clients in wireless mobile networks. In spite of importance of mobility management, currently the study of mobility management is not enough, therefore we have developed modulated Auto_Test management system for resolve the mobility management. The proposed system is composed of distance-based monitoring, location-based monitoring, scenario management, mobility management and statistic management, it makes the control by individual module. Simulation results show that the proposed system outperforms the existing systems.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.1
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• pp.44-48
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• 2008

Hole mobility characteristics of two representative biaxially strained SiGe/Si structures with high Ge contents are studied, They are single channel ($Si/Si_{1-x}Ge_x/Si$ substrate) and dual channel ($Si/Si_{1-y}Ge_y/Si_{1-x}Ge_x/Si$ substrate), where the former consists of a relaxed SiGe buffer layer with 60 % Ge content and a tensile-strained Si layer on top, and for the latter, a compressively strained SiGe layer is inserted between two layers, Owing to the hole mobility performance between a relaxed SiGe film and a compressive-strained SiGe film in the single channel and the dual channel, the hole mobility behaviors of two structures with respect to the Si cap layer thickness shows the opposite trend, Hole mobility increases with thicker Si cap layer for single channel structure, whereas it decreases with thicker Si cap layer for dual channel. This hole mobility characteristics could be easily explained by a simple capacitance model.

• The Journal of Engineering Research
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• v.8 no.1
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• pp.97-106
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• 2006

Chord system, structured P2P system based on distributed hashed table, didn't consider the mobility of mobile device. Mobility of mobile node may cause performance falloff of both mobile node and P2P network. Not only Chord system but also the greater part of P2P system didn't consider the mobility of mobile node. Recently it is researched on mobility in P2P system. In this paper, it proposed the method of the supporting mobility in chord system. Mobile node joins to the P2P network through the stationary node meaning the parents node. Mobile node require or offer the service for the parents node.

• International Journal of Advanced Culture Technology
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• v.2 no.1
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• pp.1-13
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• 2014

In next-generation wireless networks, provisioning of IP-based network architecture and seamless transmission services are very important issues for mobile nodes. For this reason, a mobility management mechanism to support global roaming is highly regarded. These technologies bring a broader life by using a global roaming account through the connection of multiple devices or technology to mobile users; they also provide real-time multimedia services. This paper presents a comprehensive performance analysis of fast handover for hierarchical mobile IPv6 (F-HMIPv6), hierarchical mobile IPv6 (HMIPv6), Proxy Mobile IPv6 (PMIPv6), and fast Proxy Mobile IPv6 (FPMIPv6) using the fluid-flow model and random-walk model. As a result, the location update cost of the PMIPv6 and FPMIPv6 is better than that of HMIPv6 and F-HMIPv6. These results suggest that the network-based mobility management technology is superior to the hierarchical mobility management technology in the mobility environment.

• Journal of Communications and Networks
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• v.7 no.2
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• pp.178-191
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• 2005

Fourth-generation (4G) wireless networks will be the IP-based cellular networks integrating Internet with the existing cellular networks. Two important issues should be concerned in the IP-based cellular networks, IP mobility, and quality-of-service (QoS) guarantees. In this paper, we proposed two mechanisms to solve the problems with IP mobility and RSVP-based QoS provisioning. First, virtual-IP (VIP) allocation scheme in areas with a large rate of handoff can minimize the wireless signaling overhead due to IP mobility. The access routers (ARs) create dynamically the VIP zone by using the measured handoff rate derived from the history of the handoff into neighboring ARs. We show that VIP allocation scheme reduces the binding update messages in the wireless link than hierarchical mobile IPv6. Second, the new advance resource reservation protocol called proportional aggregate RSVP (PA-RSVP) can minimize waste of bandwidth and soft state refresh overhead due to IP mobility. It allocates the bandwidth in advance between the mobility anchor point and neighboring ARs using proportional aggregate reservation. We also show that PA-RSVP provides an improved performance over existing protocols.

• Fashion & Textile Research Journal
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• v.21 no.2
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• pp.209-219
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• 2019

This study analyzed and compared wearer mobility for different types of clothing that also included the potential to develop firefighter station uniforms using range of motion (ROM) and electromyography (EMG). This study focused on a comparison of wearer mobility affected by different materials and shapes of the station uniforms worn under firefighter turnout gear. Japanese standard uniform (UNI), stretch-wear (ST), and compression-wear (CP) were used as station uniforms for the experiment. This study analyzed wearer movements and quantified ROM and EMG. In addition, the subjective evaluation of wearer mobility and comfort were assessed for comparisons. Nine healthy male students participated in the experiment. Wearer mobility was analyzed using ROM and EMG data obtained by measuring five motions; in addition, subjective evaluations were also obtained. As compared with the standard station uniform, ROM increased 6.8 % and 7.2 % due to stretch-wear and compression-wear. The benefits of wearing stretch material or compression material to improve muscle performance (such as reduced percent of maximum voluntary contraction) were not proven. Differences between materials and designs influenced subjective wearer comfort. In particular, the wearing of compression materials was shown best in terms of wearer comfort that may also allow greater wearer mobility.

• The Southeast Asian review
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• v.24 no.2
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• pp.207-251
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• 2014

This study explores the mobility patterns of Korean Early Study Aborad (ESA, hereafter) students in Singapore through a follow-up longitudinal case study, which was initially conducted about five years before this study. This study takes up transnational migration approach, focusing on family strategies and mobilization, which steered their mobility. Interviews with seven original families as well as 7 families additionally recruited in Singapore in 2012 were collected and analyzed by NVivo 9. In short, this study found that transnational mobility is composed of mobilities at global, regional and local levels. There were four types of mobilities; continuation of stay in Singapore, move from a third county to Singapore, return to Korea, and, what this research calls, fluid mobility. Examining the process of these mobilities shows that we need to consider at least three factors (performance of children's schooling; change of family circumstances; context of reception for both Singapore and Korea) as basic backgrounds. On this basis, the interplay between the context of receptions when aspirations for children's advancement by these transnational families made either facilitate or constrain their mobilities: contexts of Singapore and Korea may play a role of hurdle or trampoline. Also, local context of Singapore largely facilitate mobilities of Korean ESA families at both local and global levels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.343-353
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• 2018

Most local governments operate Mobility Support Centers to provide transportation convenience for the transportation vulnerable. A Mobility Support Center makes various efforts to improve the mobility of the transportation vulnerable. One of them is the operation of a Special Transportation Vehicle (STV). On the other hand, during implementation, problems, such as insufficient number of vehicles and high demand, have been found. Nevertheless, improving the service by providing a large amount of STV can be a problem in terms of the budget. Therefore, it is necessary to gather opinions of the users and identify the problems during the utilization of a Mobility Support Center. Moreover, it is necessary to improve various services to achieve a better and more comfortable utilization. In this research, SEM was used to analyze the importance of the Mobility Support Center for the transportation vulnerable. The importance and performance drawn and examined through an analysis and questionnaire survey were used to propose IPA results that consider the importance and performance at the same time. In addition, this research also suggest a service improvement priority based on the analysis result. For the analysis, this research conducted a questionnaire survey on the actual users and their guardians who use STV in Cheonan-city, as well as factor analysis and reliability analysis. The results showed that the 'Charge system' is not affected by the service because it is fully satisfied by the low price when compared to public transportation. In addition, 'Vehicle use' is more important than 'Convenience' service. IPA analysis showed that it is necessary to improve the priority, kindness, waiting time, and call center response for the better and more comfortable utilization of Mobility Support Centers for the transportation vulnerable.