Sun-Hwa Lim

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Recently, a lot of studies have been done in wireless sensor networks (WSNs) based on IEEE 802.15.4. While a sensor device transmits data to a PAN coordinator via a coordinator, the failure of radio communications may be occurred between a coordinator and a PAN coordinator. A coordinator may conclude that it has been orphaned and then perform the orphan(More)
In this paper, we will introduce the necessity of real-time safety monitoring system for high-speed railway vehicle and propose a new type of safety monitoring system using a low-power wireless connection. To verify the proposed safety monitoring system is feasible, we measure the packet error rate on the moving train and show the analyzed results.
Wireless sensor networks (WSNs) have been widely applied to a various areas. Especially in recent years, there has been an increasing interest in the adoption of emerging sensing technologies for a railway infrastructure monitoring. However, because the wireless communication of a railway is operated between sensor devices in poor environments such as high(More)
Train accidents continuously occur due to a variety of causes (carelessness by the conductor, broken wheels, disaster during train movements, etc.). To prevent train-related accidents in advance, it is considered the monitoring train systems with wireless sensor networks (WSNs). In this paper, we propose an efficient algorithm to dynamically configure(More)
A lot of research have been done in wireless sensor networks (WSNs) based on IEEE 802.15.4. However, there is no study that the status of a device is monitored by the PAN coordinator in the IEEE 802.15.4 technology in order to reduce radio resource wastage. In this paper, we propose a procedure that the PAN coordinator can detect that the operation of a(More)
With the rapid growth of wireless technologies, there will be coexistent heterogeneous wireless networks environment within a few years. For example, there may be coexistent current wireless LAN systems based on widely available IEEE 802.11 and a wireless system based on proprietary wireless standard with different AAA mechanisms such as RADIUS and(More)
In this case report, we present a mock-transduced bone marrow (BM) transplantation in a mouse, which was found moribund and autopsied to evaluate pathogenesis. Macroscopically, red discoloration of systemic organs was observed. Hematological values revealed a decrease in white blood cells, red blood cells, hematocrit, hemoglobin, and platelets, but an(More)
With the growth of wireless technologies rapidly, there will be coexist heterogeneous wireless LANs environment within a few years. For example, there may be coexist current wireless LAN systems based widely available 802.11 and a wireless LAN system based proprietary wireless LAN standard with different AAA mechanisms such as RADIUS and Diameter. In case(More)
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