• Journal of the Korea Society of Computer and Information
• /
• v.16 no.12
• /
• pp.265-271
• /
• 2011

High-quality customized services demand was growing due to the increase of aging, extremely nuclear family, disaster vulnerable of society. Ambulance service is required of fast and professional rescue and emergency service because of preventable death rate such as acute diseases, cerebral and cardiovascular diseases, suicides, etc. was higher than in developed countries. First aid will be available using patients information when emergency occurs, before arriving at the hospital. And emergency department is equipped with that patient care can be prepared in advance, increase the efficiency of emergency care. We received a variety of complex emergency call using high social awareness of 119 number and propose an efficient emergency medical service advancement strategy building an integrated response system with relevant organization.

• Journal of the Korea Society for Simulation
• /
• v.23 no.4
• /
• pp.97-109
• /
• 2014

Personal rapid transit (PRT) is a new transportation system, which is energy efficient and brings high quality of customer service. Customers arrive dynamically at stations and request transportation service. In this paper, we propose a new online PRT dispatching algorithm for pickup and delivery of customers. We adopt the nearest neighbor dispatching rule, which is known as performing well in general. We extend the rule with bipartite matching in order to deal with multiple vehicles and customers at the same time. We suggest a systematic way for selecting vehicles that will be considered to be dispatched, since the scope with which vehicles are selected may affect the system performance. We regard the empty travel distance of vehicles and the customer waiting time as the performance measures. By using simulation experiments, it has been examined that the scope of dispatching affects the system performance. The proposed algorithm has been validated by comparing with other dispatching rules for transportation services. We have shown that our algorithm is more suitable for PRT operating environment than other dispatching rules.

• Journal of Internet Computing and Services
• /
• v.11 no.2
• /
• pp.129-142
• /
• 2010

The ubiquitous healthcare environment is one of the systems that benefit from wireless sensor network. But one of the challenges with wireless sensor network is its high loss rates when transmitting data. Data from the biosensors may not reach the base stations which can result in missing values. This paper proposes the Health Monitor Agent (HMA) to gather data from the base stations, predict missing values, classify symptom patterns into medical conditions, and take appropriate action in case of emergency. This agent is applied in the Ubiquitous Healthcare Environment and uses data from the biosensors and from the patient’s medical history as symptom patterns to recognize medical conditions. In the event of missing data, the HMA uses a predictive algorithm to fill missing values in the symptom patterns before classification. Simulation results show that the predictive algorithm using the HMA makes classification of the symptom patterns more accurate than other methods.

• Journal of Chest Surgery
• /
• v.41 no.4
• /
• pp.536-539
• /
• 2008

We present a case with a foreign body in the left pulmonary artery, found in a traffic accident victim. A 52-year-old woman sitting in the passenger side of a car had massive bleeding and near complete amputation of her right forearm in addition to multiple rib fractures and a hemopneumothorax. At arrival to the emergency room, the patient had signs of shock; she was anemic, drowsy and hypotensive. A large volume of blood and crystalloid fluids were administered via the left subclavian vein with a rapid infusion device (Level $1^{(R)}$). As the lung contusion improved, a foreign body was noticed in the left lung field on plain x-rays. Pulmonary angiography was performed and revealed a 15 cm foreign body in the left basal segment of the common pulmonary artery. The foreign body was successfully retrieved using vascular forceps via the percutaneous femoral vein approach.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.8 no.1
• /
• pp.39-45
• /
• 2008

High-Rate Wireless Personal Area Networks (HR-WPANs) in IEEE 802.15.3 standard use a TIme Devision Multiple Access (TDMA) protocol to support isochronous traffic. Isochronous traffic requires a delay-bounded service. However, the HR-WPAN standard suffers from long access delay and association delay. In this paper, we propose an enhanced MAC protocol for the delay-bounded traffic. This proposed protocol provides a way that a central node is able to collect traffic status on all member nodes. Furthermore, by utilizing the information, a scheduling algorithm is also proposed in order to synchronize the instant of a packet transmission with that of the packet arrival. With the proposed protocol and algorithm, the delay of access and association can be reduced. Performance analysis is carried out and the significant performance enhancement is observed.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.8 no.5
• /
• pp.187-195
• /
• 2008

In MANET, it is important to efficiently manage data objects and traffic to improve network throughput and response time. This paper proposes a connection-degree based data object search and replication scheme in mobile ad-hoc networks. In this method, information about the path data object providers is stored at the cache of a cluster header at which lots of queries arrive, so that, to reduce the load of the cluster header, replicas can be created at its neighboring nodes. The method proposes an algorithm that picks up a cluster header among mobile nodes and makes it possible to search for and utilize adaptive and up-to-date information in MANET. The method is expected to be effective since it enables access to data objects in spite of broken links among mobile nodes with an enhancement in network response time of searching and a decrease in communication costs. The efficiency of this system was verified via simulation.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.49 no.11
• /
• pp.9-16
• /
• 2012

In this paper, we focus on end-to-end transfer delay improvement by using network coding and propose a scheme where a message is divided into several packets which are network coded generating additional redundancy with the results that the number of transmitted packets increases. In networks with high coefficient of variation of transfer time, increased number of packets could reduce the transfer time of the message to a destination. For the proposed scheme, we investigate the optimum number of divided packets and redundancy considering transfer delay reduction and additional transmission cost caused by using network coding under the restriction of maximum transmission packet size. From the results of the investigation, we see that the proposed scheme is effective in networks having high variability of transfer time and would be very useful and practical especially for the case that expedited deliveries of messages are needed.

• Journal of Korea Game Society
• /
• v.11 no.1
• /
• pp.111-120
• /
• 2011

It is important to realistically simulate group behaviors of the multi-agents in virtual worlds. While most researchers have focused on their group behaviors in an open space, this paper studies their group behaviors by using steering force in an enclosed space. Agents have a common target and should move towards it in an enclosed space while avoiding collision with other agents. Under those environments, three possible models of agents are proposed and the six steering forces needed in each model are also proposed. In order to show the correctness of the proposed models, they were simulated. Our simulation results showed that the proposed models only using steering forces operate well in the enclosed space although it requires a different period of time for each agent to arrive at its target depending on the walls and doors.

• Journal of Korea Multimedia Society
• /
• v.8 no.2
• /
• pp.192-200
• /
• 2005

In this paper, an improved User Parameter Control (UPC) algorithm is proposed for controlling traffic in ATM networks. The present algorithm consists of Cell Buffer, Red Token Pool, Green Token Pool, and Spacer. A token is generated at a certain time period, and the tokens are consumed one each time a cell arrives. At this time, if the delay element, named Spacer, is empty, the cell comes into the network. On the other hand, if Spacer is not empty, the cell cannot come into the network. In addition, in the case that tokens do not exist in Token Pool, the corresponding cell is thrown away The arbitrary function of the token used in this paper is removed. Instead, the token is used only to control network traffic. This research proposes new UPC Algorithm to improve the current cell delay rate and cell loss rate by dynamically adopting the delay element, named Spacer, with respect to the traffic condition, which is different from controlling that the cell comes into the network after a certain delay time period.

• Journal of Korea Multimedia Society
• /
• v.16 no.9
• /
• pp.1077-1088
• /
• 2013

As broadcasting is the process that a node sends a packet to all nodes in the network. it is basic process used for discovering of a routes to a node and disseminating of control information message in Mobile Ad hoc NETwork (MANET). In this paper, we propose dynamically adjusted probabilistic mechanism based on distance ratio and node density for broadcasting in MANETs. The distance ratio can be calculated as the ratio of the radio strength length to the distance from sender of a node, and node density can be get from 1-hop nodes of neighbours. A mobile node receiving broadcast packets determines the probability of rebroadcasting considering distance ratio and node density of itself. Rebroadcast probability will be set as low value to a node which is located in nearby area of sender and has high 1-hop node density, So it reduces packets transmission caused by the early die-out of rebroadcast packets. Compared with the simple flooding and fixed probabilistic flooding by simulation, our approach shows better performances results. Proposed algorithm can reduce the rebroadcast packet delivery more than 30% without scanting reachability, where as it shows up to 96% reachability compared with flooding.