이수경 교수

There are currently a large variety of wireless access networks, including the emerging vehicular ad hoc networks (VANETs). A large variety of applications utilizing these networks will demand features such as real-time, high-availability, and even instantaneous high-bandwidth in some cases. Therefore, it is imperative for network service providers to make the best possible use of the combined resources of available heterogeneous networks (wireless area networks (WLANs), Universal Mobile Telecom

This study has analyzed females' motives and psychological experiences related to appearance-enhancement seeking behavior(weight control practice and cosmetic surgery). In this study, in-depth interviews were carried out to 11 females who had experienced weight control practices and cosmetic surgery in June 2001. There is social standard in ideal body image. One perceive a physical idea and own body through society(mass media, reference group), others and clothing, and recognize the ideal body a

Optical burst switching (OBS) is a very promising switching technology for realization of an economical optical Internet. In OBS networks, when contention occurs at an intermediate switch, two or more bursts that are in contention can be lost because a forwarding path reservation is not made for a burst until a control message for the burst arrives. That is the reason why one of the critical design issues in OBS is finding ways to minimize burst dropping resulting from resource contention. In th

One of the critical design issues in optical burst switching (OBS) networks is finding ways to minimize burst dropping resulting from resource contention. The existing variants of the basic deflection routing schemes all lack the ability to determine the alternate route based on clear performance objectives. In this paper, we present contention-based limited deflection routing (CLDR) scheme, which sequentially performs the following: (1) based on certain performance criteria, dynamically determi

Data traffic demands in cellular networks today are increasing at an exponential rate, giving rise to the development of heterogeneous networks (HetNets), in which small cells complement traditional macro cells by extending coverage to indoor areas. However, the deployment of small cells as parts of HetNets creates a key challenge for operators' careful network planning. In particular, massive and unplanned deployment of base stations can cause high interference, resulting in highly degrading ne

In this letter, we propose an efficient power-saving mechanism using paging of cellular networks for WLAN in heterogeneous wireless networks, where WLAN interface is turned off during idle state without any periodic wake-up in order to save power consumption while at the same time, the existing paging of cellular network is utilized in place of beacons in WLAN. For the proposed mechanism, the mean power consumption is investigated via analytical and simulation results.

Skiing is one of the most popular winter sports in the world. Even though the equipment has been improved for preventing injuries during skiing, injury risks of the lower extremity are still high. It is necessary to investigate injury risk by motion analysis during skiing. The wearable motion capture system consisting of inertial sensors and insole pressure sensors can be utilized due to restrictions of conventional optical motion capture system. In this study, the motions for short-and middle-t

In heterogeneous wireless networks, there have been several efforts aimed at having mobile devices equipped with multiple interfaces connect optimally to the access network that minimizes their power consumption. However, a study of existing schemes notes that in the idle state, a device with both a WLAN and a WWAN interface need to keep both interfaces "on" in order to receive periodic beacon messages from the AP (WLAN) and downlink control information from the base station (WWAN), resulting in

In optical burst-switched (OBS) networks, the loss of burst containing a number of IP packets occurs mostly due to contention rather than congestion so that a TO (Time Out) event will trigger unnecessary TCP congestion control resulting in significant throughput degradation (X. Yu, et al., 2004). Therefore, in this letter, we propose a drop policy (DP) with burst retransmission where a new concept of retransmission-count for bursts is introduced to mitigate unnecessary TCP congestion control. Th