• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.1
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• pp.187-195
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• 2013

In this paper, we propose a transmission power control scheme for performance improvement of VANET using STPC algorithm considering traffic-flow model. In traffic congestion, a transmission power between car and car increases the collision probability of control messages, which causes the problems to decrease the performance of VANET. The proposed scheme is evaluated by OPNet modeler 16.0 for analyzing its performance and effectiveness in terms of end-to-end delays in hops, packet success probability, and throughput. The simulation result show that the proposed scheme reduces a delay in hops and increases high packet transmission success ratio. Furthermore, a throughput under high density traffic is improved effectively.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.7
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• pp.570-577
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• 2016

This paper proposes the design of a novel distributed message management scheme using a message-oriented management and analysis tool (MOMAT) for naval combat system (NCS) middle-ware. If a message is not guaranteed real-time of the NCS with each node, it causes the loss of data and decreases the reliability of systems. To solve these problems, improved message management schemes are proposed. Message management schemes are considering a real-time user management scheme and a real-time traffic management scheme. The proposed schemes are simulated with a developed simulation tool, data publisher, and subscriber connected through nodes in middle-ware. The simulation results show improved results in terms of message round-trip time (RTT), End-to-End delay, and throughput.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.10
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• pp.76-82
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• 2007

Recently, researches related MANET are progressing dynamically in points of view which MANET need no additional infra and guarantee node mobility. Node mobility in MANET is becoming more important, as people interest in using Ad hoc network under a concept of node mobility as fast automobile not walking. when nodes move fast, there are many problems headed by high cost for searching destination and routing. To deal with this problems We propose new routing protocol, No path-Location Aided Routing (N-LAR). Our algorithm has a better performance in terms of end-to-end delay, packet delivery ratio in MANET with High mobility.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.53-58
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• 2015

Background: The purpose of this study was to assess the the efficacy of oral glutamine (GLN) in prevention of acute radiation-induced esophagitis in patients with lung cancer and determine the predictive role of clinical and dosimetric parameters. Materials and Methods: Thirty-two patients diagnosed with lung cancer were studied prospectively. Sixteen patients (50%) received prophylactic powdered GLN orally in doses of 10g/8h. Patients were treated 2 Gy per fraction daily, 5 days a week. We evaluated the grading of esophagitis daily at the end of each fraction of each treatment day until a cumulative dose of 50 Gy was reached. The primary end point was radiation-induced esophagitis. Results: All patients tolerated GLN well. Toxicity grade, weight loss, serum cytokine levels and esophageal transit times exhibited statistically significant improvement in the GLN receiving group. GLN suppressed the inflammation related to the disease and treatment and reduced toxicity with statistical significance. Conclusions: This study suggests a benefical role of oral GLN use in prevention and/or delay of radiation-induced esophagitis, in terms of esophageal transit time and serum immunological parameters, as well as weight loss.

• The KIPS Transactions:PartC
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• v.11C no.7 s.96
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• pp.895-904
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• 2004

Due to the frequent and unpredictable topology changes, multicast still remains as challenge and no one-size-fits-all protocol could serve all kinds of needs in mobile ad hoc network. In this paper, we propose a novel scheme of Hierarchical Eulerian Ring Oriented Multicast Architecture (HEROMA) over mobile ad hoc network. It has features that concentrate on efficiency and robustness simultaneously. It is also an application-driven proposal for hazard detection. Architectures including Eulerian ring, hierarchy and multicast agent are investigated in detail Simulation results different level of improvements on control traffic, end-to-end delay and packet delivery ratio by comparing with tree-based and mesh-based multicast protocols.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.12
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• pp.5928-5947
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• 2019

Multicast Mesh based Mobile Ad-hoc NETworks (MANETs) provide efficient data transmission in energy restraint areas without a fixed infrastructure. In this paper, the authors present an improved version of protocol SLIMMER developed by them earlier, and name it SLIMMER-SN. Most mesh-based protocols suffer from redundancy; however, the proposed protocol controls redundancy through the concept of forwarding nodes. The proposed protocol uses remaining energy of a node to decide its energy efficiency. For measuring stability, a new metric called Stability of Node (SN) has been introduced which depends on transmission range, node density and node velocity. For data transfer, a weighted cost function selects the most energy efficient nodes / most stable nodes or a weighted combination of both. This makes the node selection criteria more dynamic. The protocol works in two steps: (1) calculating SN and (2) using SN value in the weighted cost function for selection of nodes. The study compared the proposed protocol, with other mesh-based protocols PUMA and SLIMMER, based on packet delivery ratio (PDR), throughput, end-to-end delay and average energy consumption under different simulation conditions. Results clearly demonstrate that SLIMMER-SN outperformed both PUMA and SLIMMER.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.10B
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• pp.1665-1674
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• 2000

This paper treats the interworking of LAN-based networks like TCP over the ATM protocol stack in an ATM multicast session. Multicast connection will cause CIP since multicast group members form a connection tree by some tree methods and share the connected tree. The paper solve the CIP problem through a block-by-block transmission using ABT/IT method. ABT/IT RM cell is modified and block scheduling algorithm considering the traffic types is applied to each ATM switch using the enhanced RM cell. Block scheduling algorithm will avoid the indiscriminate discard of UBR traffic when congestion occurs and it can provide an efficient and fair service. The paper builds a block scheduler system and suggests the block scheduling algorithm for a multicast session in an ATM switch. UBR traffics arriving at the switch trough each VC is classified by the traffic type and stored at class buffer and thereafter indisciminately transmitted. When block scheduling algorithm is applied it will improve the UBR traffic performance such as end-to-end delay cell block loss ration etc. This paper evaluated the performance of block scheduling algorithm through the simulation using the C language and data structure.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.10C
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• pp.975-982
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• 2009

In this paper, we propose a novel mixing algorithm for multiple video streams, which can guarantee low complexity and low end-to-end delay. In the propose algorithm, we change the syntax bitstream in the compressed domain. And we mix the H.264/AVC video streams by coded slice unit. The syntax bitstream for a mixing changes according to the arrangement of videos streams in which it organizes the mixing screen layout. Experimental results show more than 4 video streams could be mixed at high speed. Moreover, it could display in the player which it supports the standard H.264/AVC without the picture quality loss.

• IEMEK Journal of Embedded Systems and Applications
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• v.13 no.2
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• pp.83-91
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• 2018

With the development of IT (Information Technology) technology, embedded system and network technology are combined and used in various environments such as military environment as well as everyday life. In this paper, we propose a new airdropped distributed mobility model (ADMM) modeling the dispersion falling of the direct shot of a cluster bomb, and we compare and analyze some representative MANET routing protocols in ADMM in ns-3 simulator. As a result of the analysis, we show OLSR routing protocol is promising in ADMM environment in the view points of packet delivery ratio (PDR), end to end delay, and jitter. In addition, we propose a new adaptation scheme for OLSR, AND-OLSR (Average Node Distance based adaptive-OLSR) to improve the original OLSR in ADMM environment. The new protocol calculates the average node distance, adapts the period of the control message based on the average node distance increasing rate. Through the simulation study, we show that the proposed AND-OLSR outperforms the original OLSR in PDR and control message overhead.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.8B
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• pp.712-721
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• 2012

In this paper, we propose an Enhanced cross-layer Geographic Forwarding (EGF) protocol for wireless sensor networks (WSNs). EGF uses an optimal back-off time to make the packet forwarding decisions using only source and destination's location information and energy cost without information about neighbor nodes' location or the number of one hop neighbor nodes. EGF is also a cross-layer protocol by combining efficient asynchronous MAC and geographic routing protocol. The proposed protocol can find optimal next hop location quickly without broadcasting node's location update and with minimizing overhead. In our performance evaluation, EGF has better performance in terms of packet success ratio, energy efficiency and end-to-end delay in wireless sensor networks.