• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.05a
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• pp.513-516
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• 2008

The sensor node's performance is expected to be improved and the price will be largely decreased. As USN-applied field is expanded, multiple application services are expected to be provided through one USN soon. Multiple applications be required a periodic data reporting, consecutive information monitoring, event-driven data and query-based data as the data pattern that USN is delivered. Accordingly, the mechanism which can assure QoS according to each data characteristic is required. In this paper, A proposed protocol apply the duty cycle of S-MAC protocol variably and flexible according QoS level. This method largely reduces the delay on the delay-sensitive traffic, while keeping the energy efficiency.

• The Journal of Information Technology
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• v.9 no.4
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• pp.57-63
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• 2006

The intelligent elder brother groove network robot service the new broadband presence line is conversionce application service. Robot control data transmission hazard UDP packet of the remote control data which stands duplication necessary to transmit. TCP the error ratio to be high qualitative recording transmission pattern it of the transmission unit and is irregular the distance is distant to show and also the transmission lag is visible increases. The recording packet drop whose UDP degree error ratio will be high is frequent and does not arrive packet little by little increases is a possibility of knowing in the transmission unit. The technique which it proposes with traffic pattern of the transmission unit is visible the transfer characteristic of the same shape from 1% packet error ratio degree. The effective transmission technique of the robot control data which puts a base in UDP protocols was proposed from the present paper. Following research it leads and it follows the duplication transmission number of time in error rate of radio link and it was thought all that controls petty the research of the mechanism which progresses is necessary.

• Journal of Korean Society of Transportation
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• v.25 no.5
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• pp.149-160
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• 2007

Automobile black boxes store and provide accident and driving information. The accident and driving information can be utilized to build scientific traffic-event database and can be applied in various industries. The objective of this study is to develop a recognition system of dangerous driving through analyzing the driving characteristic patterns. In this paper, possible dangerous driving models are classified into four models on the basis of vehicle behaviors(acceleration, deceleration, rotation) and accident types from existing statistical data. Dangerous driving data have been acquired through vehicle tests using automobile black boxes. Characteristics of driving patterns have been analyzed in order to classify dangerous driving models. For the recognition of dangerous driving, this study selected critical value of each dangerous driving model and developed the recognition algorithm of dangerous driving. The study has been verified by the application of recognition algorithm of dangerous driving and vehicle tests using automobile black boxes. The presented recognition methods of dangerous driving can be used for on-line/off-line management of drivers and vehicles.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.2
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• pp.164-170
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• 2013

With the introduction of increasingly large-sized ships, the conditions of main domestic port facilities remain the same as in the past. So, there is high probability that marine traffic congestion can occur at the certain ship's routes. The standard ship's length used to assess the marine traffic congestion of domestic trade port is 70 meters. It has been in use for the last 30 years, so, its usefulness is highly recommended for review. This study deeply analyzes the tendency of ship's dimensional changes according to recent enlargement of ship's size by utilizing the particulars of 60,000 ships saved in domestic Port-MIS database and suggests the standard ship's length by figuring out the correlation between length of ship and gross tonnage. In addition, the basis of statistical data on the ship's tonnage in domestic trade over the last five years suggests the standard ship's length by deriving the reference point of cumulative incidences that occupy more than over 50 %, except for small vessels. It is necessary to consider the characteristic of each domestic trade port before the actual application of suggested standard ship's length.

• Convergence Security Journal
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• v.4 no.3
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• pp.1-8
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• 2004

Large distributed systems such as computational and data grids require that a substantial amount of monitoring data be collected for various tasks such as fault detection, performance analysis, performance tuning, performance prediction, security analysis and scheduling. to cope with this problem, they are needed network monitoring architecture which can collect various network characteristic and analyze network security state. In this paper, we suggest network performance and security analysis system based on network monitoring. The System suggest that users can see distance network state with tuning network parameters.

• The Journal of the Korea Contents Association
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• v.4 no.4
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• pp.107-112
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• 2004

As the internet service evolves fast recently, guarantee request of QoS (Quality of Service) by characteristic of traffic source as well as high rate of data is going greatest. Accordingly intemet service technology also is changing rapidly, technology that guarantee QoS in existent network service technology is developed or network model that guarantee new QoS is presented. By DiffServ-aware-MPLS network that present in IETF (Internet Engineering Task Force) to guarantee QoS in this treatise does comparative analysis with existent network model, relative show that is superior, and present direction that compose next generation network wish to.

• Journal of Korean Association for Spatial Structures
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• v.7 no.4
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• pp.97-104
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• 2007

This paper is concerned with the vibration characteristics of medium-rise building, which severely vibrated by vehicles. The field vibration measurement was employed for finding the vibration source and vibration reducing method. Time domain data from measurements were also utilized for vibration characteristics, such as effect of buses and subways-induced vibration on the floor vibration of the building. effectiveness of the vibration reducing method was also demonstrated.

• Journal of the Korea Society of Computer and Information
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• v.10 no.5 s.37
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• pp.123-132
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• 2005

In this Paper, we present an improvement of switch node for wavelength multiplex optical network. Currently because of quick increase of internet traffic a big network capacity is demanded. Wavelength multiplex optical network Provides the data transfer of high speed and the transparent characteristic of the data. Therefore optic network configuration is the most powerful technology in the future. It will be able to control the massive traffic from the optical network in order to transmit the multimedia information of very many quantify. Consequently the node where the traffic control is Possible, is demanded. The optical switch node which manages efficiently the multiple wavelength was Proposed. This switch is composed of a optical switch module for switching and a wavelength converter module for wavelength conversion. It will be able to compose the switch fabric without optical/electro or electro/optical conversion using optical MEMS(Micro Electro Mechanical Switches) module. Finally, we present the good test result regarding the operational qualify of the switch fabric and the performance of optical signal from the switch node. The proposed switch node of the optic network will be able to control the massive traffic with all optical.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.7
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• pp.528-537
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• 2014

As the data traffic between ships and a land station continuously increase through the shipbuilding-IT convergence, several wireless communication technologies are being studied to process large amounts of data traffic. In particular, the multi-antenna system is one of the most expected technologies to provide high throughput. This paper proposes an algorithm for the base station to select the ship in consideration of channel characteristics and the transmission angle for a beam of the land station in spatial multiplexing marine communication systems. We increase the system capacity by maximizing the received signal strength of the ship using clustering characteristic of the radio channel. Also, we reduce the time to select the ship by excluding the ship with the large interference between the beams. On our computer simulation, the proposed scheme dramatically reduces the computational complexity with a little sacrifice of the throughput.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.7
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• pp.3309-3328
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• 2017

The application of Internet of Things (IoT) in the next generation cellular networks imposes a new characteristic on the data traffic, where a massive number of small packets need to be transmitted. In addition, some emerging IoT-based emergency services require a real-time data delivery within a few milliseconds, referring to as ultra-low latency transmission. However, current techniques cannot provide such a low latency in combination with a mice-flow traffic. In this paper, we propose a dynamic resource reservation schema based on an air-interface slicing scheme in the context of a massive number of sensors with emergency flows. The proposed schema can achieve an air-interface latency of a few milliseconds by means of allowing emergency flows to be transported through a dedicated radio connection with guaranteed network resources. In order to schedule the delay-sensitive flows immediately, dynamic resource updating, silence-probability based collision avoidance, and window-based re-transmission are introduced to combine with the frame-slotted Aloha protocol. To evaluate performance of the proposed schema, a probabilistic model is provided to derive the analytical results, which are compared with the numerical results from Monte-Carlo simulations.