• Proceedings of the IEEK Conference
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• 2004.06a
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• pp.119-122
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• 2004

This mobile oriented Ad-hoc network yet steps on development level, related issues and standardization are progressing. This paper presented ad-hoc network's overview and overall property, followed by routing scheme that must be setup for communication between each nodes. Among several routing scheme proposed for standardization, ZRP that is foaled by this paper, is hybrid type algorithm, and only includes advantages of others This paper presented running process and implementation method, result that is made from network simulation, shows analysis of each parameter values's change. Each parameters changed with many differences according to Zone radius and communication node's location from simualtion that was performed changing a number of nodes and a velocity of nodes.

• IEMEK Journal of Embedded Systems and Applications
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• v.12 no.6
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• pp.351-358
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• 2017

The most common communication interface for automotive electronic control devices is CAN (Controller Area Network). Sine CAN was first adopted to Daimler vehicles in 1991, all of automobile manufacturers use the CAN communication for in-vehicle networks. However, as the number of electronic control devices connected to the CAN network rapidly increases, the CAN protocol reaches the limit of technology. To overcome this limitation, Bosch introduced the new communication protocol, that is CAN-FD (Flexible Data-rate). In this paper, we analyze the characteristics and limitations of CAN-FD communication according to the topology under the in-vehicle wiring harness environment designed based on the existing classic CAN communication.

• International journal of advanced smart convergence
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• v.8 no.4
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• pp.169-178
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• 2019

Due to the characteristics of an ad hoc network without a control center, self-organization, and flexible topology, the trust evaluation of the nodes in the network is extremely difficult. Based on the analysis of ad hoc networks and the blockchain technology, a blockchain-based node-level trust evaluation model is proposed. The concepts of the node trust degree of the HASH list on the blockchain and the perfect reward and punishment mechanism are adopted to construct the node trust evaluation model of the ad hoc network. According to the needs of different applications the network security level can be dynamically adjusted through changes in the trust threshold. The simulation experiments demonstrate that ad-hoc on-demand distance vector(AODV) Routing protocol based on this model of multicast-AODV(MAODV) routing protocol shows a significant improvement in security compared with the traditional AODV and on-demand multipath distance vector(AOMDV) routing protocols.

• Journal of Korean Institute of Industrial Engineers
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• v.23 no.4
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• pp.687-698
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• 1997

In this paper, a Variation of Blast with Go-Back-N(V-BGBN) protocol is proposed, which differs from Blast with Go-Back-N(BGBN) and Blast with Full Retransmission on Error(BFRE) protocols in the retransmission strategy of packets. Performances of these three protocols under correlated packet errors are analyzed. Throughput efficiency of an arbitrary packet is obtained under the assumption that the round trip delay and the packet length are respectively constant. Recursive formula and difference equations are used as analytical tools. Correlation of packet errors is modelled by a two state Markov chain. The throughput efficiencies under these protocols are compared. V-BGBN protocol is shown to be superior to other two protocols in high speed network.

• 전자공학회논문지 IE
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• v.47 no.2
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• pp.54-59
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• 2010

This paper suggests a new data link protocol with an adaptive frame length control scheme for wireless data networks which is subject to errors that occur with time variance. We analyze the proposed scheme under a two-state markov block interference(BI) model. Numerical results show that the proposed scheme can achieve high throughput performance for both dense and diffuse burst noise channels.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.05a
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• pp.1037-1040
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• 2006

This paper presents an efficient overlay multicast routing protocol (ROMP) and its architecture. ROMP using GPS and region map stands on the basis of scalable 2-tiered multicast architecture and maintains a global overlay multicast tree through reactive fashion. With this approach, the coarse-grain location-awareness for an efficient overlay multicasting and the determination of hot-spot area for efficient data delivery are feasible. The simulation results show that the localized control packets of ROMP prevent the overlay control packets from squandering the physical network resources.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.711-713
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• 2004

In the past time, the protection relay did only a protection function. Currently, its upgraded device i.e. IED(Intelligent Electric Device) has been designed to protect, control, and monitor the whole power system automatically. Also the device is desired to successfully measure important elements of the power system. This paper considers design method of a digital protection IED with a function of measuring various elements and a communication function. The protection IED is composed of the specific function modules that are signal process module, communication module, input/output module and main control module. A signal process module use a DSP processor for analysis of input signal. Main control module use a embedded processor, Xscale, that has an ARM Core. The communication protocol uses IEC61850 protocol that becomes standard in the future. The protection IED is able to process mass information with high-performance processor. As each function module is designed individually, the reliability of the device can be enhanced.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.5
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• pp.218-225
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• 2001

This paper analyses the performance of network system using the CAN(Controller Area Network) protocol. Given messages are assumed to be scheduled by the DMS(Deadline Monotonic Scheduling) algorithm. The mathematical models for time-delay that can be occurred between CAN nodes are defined. The effectiveness of modeling is shown by comparing the difference of time-delay between simulations and practical experiments. We analyse the results according to the variation of factors, such as the number of nodes, the transmission speed, the message size and the number of aperiodic messages through simulation and confirm the real-time performance of lower priority messages. We also investigate the real-time performance of periodic messages when aperiodic message generates.

• The Journal of the Korean dental association
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• v.50 no.11
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• pp.682-688
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• 2012

Surgery first approach in orthognathic surgery is to proceed the orthognathic surgery without preoperative orthodontic treatment. This approach has many advantages, which include a shorter total treatment period, a high level of patient satisfaction due to immediate post-surgical facial improvement, easy postoperative orthodontic treatment due to early normalization of skeletal muscle, and the rapid tooth movement reflecting the regional accelerated phenomenon. However instability due to transient occlusal interference after surgery make worse of long-term skeletal stability. Especially increasing of vertical occlusion caused by interference of interbicupid and molar happen postsurgical skeletal change. Until now, there is no common consensus about treatment protocol of surgery first approach in orthognathic surgery. The purpose of this paper is to introduce our treatment protocol of the surgery first approach and to evaluate indication and limitation with case analysis.

• Journal of applied mathematics & informatics
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• v.26 no.1_2
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• pp.235-249
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• 2008

On-demand routing protocol in ad hoc network is that establishes a route to a destination node only when it is required by a source node. But, it is necessary to reestablish a new route when an active route breaks down. The reconstruction process establishes another route by flooding messages from the source to the destination, cause not only heavy traffic but also long delays in route discovery. A good method for analyzing performance of protocols is important for deriving better systems. In this paper, we suggest the numerical formulas of a representative on-demand routing protocol AODV, ARMP, and RRAODV to estimate the performance of these routing protocols for analyzing the performance of these protocols. The proposed analytical models are very simple and straightforward. The results of analysis show good agreement with the results of computer simulations.