• Journal of the Korean Operations Research and Management Science Society
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• v.28 no.2
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• pp.139-155
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• 2003

The aim of this study is to identify the data traffic capacity of 3G mobile communication networks, especially of cdma2000-1X networks. Three-layered ON/OFF traffic model is used to describe the dynamics of data traffics and the process of data transmission such as packet scheduling. We construct a simulator fully incorporating packet handling process of cdma2000-lX data network as well as three-layered ON/OFF traffic model describing the behavior of source data traffics. To get influence of traffic parameters on performance measures, the extensive simulations were performed for several data sets which are obtained from real trace data or previous studies. The experimental results show that the engineered throughput satisfying QoS criteria is approximately 25% of total capacity. Finally, some proposals to improve the system capacity are followed.

• Journal of Korean Port Research
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• v.11 no.2
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• pp.173-189
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• 1997

Whether over taking or parallel sailing of two or more vessels is allowable on marine traffic route or not, the traffic congestion due to traffic volume has to be evaluated separately. In Gaduk-sudo, overtaking or parallel sailing is so allowable that the Bumper Model is introduced to evaluated the traffic congestion. But the channels within the habour limit such as the route of Ulsan New Port are so prohibited overtaking or parallel sailing that the traffic congestion has to be evaluated by using theoretical traffic capacity or by traffic simulation. In this paper, the congestion of Southern New Port and Mipo Port was evaluated the congestion by using theoretical traffic capacity and the other area of Ulsan Port by traffic simulation. The incresed traffic volumes on Ulsan Channels according to Ulsan New Port Development in 2011 were evaluated to have no effect with the traffic congestion.

• Journal of Korean Institute of Industrial Engineers
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• v.22 no.4
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• pp.551-565
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• 1996

We present the required handover capacity of personal communication service exchange(PCX). We use the flow-based mobility model. The dimension of PCX area and the number of radio port controller(RPC) in a PCX are determined according to the traffic carrying capacity of switching system and RPC. For the rectangular or square-shaped PCX/RPC area and the personal communication service environment with pedestrian traffic, we perform numerical computations to investigate the sensitivity to cell size, portable station(PS) terminating traffic, its density, and its average speed. The results how that the size of PCX/RPC area decreases as the PS terminating traffic and the PS density increase, and the PCX handover capacity required is more than 73,000 in the number of transactions per hour.

• Korean Management Science Review
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• v.19 no.1
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• pp.29-38
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• 2002

Due to the rapid increase In the Internet traffic volume, ISPs are faced with the definite need of the expansion of server capacity. In order to Provide prompt services for customers and still prevent excessive facility cost, it is critical to determine the optimum level of internet server capacity. The purpose of this Paper is to provide a simple but effective strategy on the expansion of servers capacity according to the increase in internet traffic. We model an internet server as an M/G/m/m queueing system and derive an efficient method to compute the loss probability which, In turn, Is used as a basis to determine proper server capacity. The Process of estimating the traffic parameter values at each server based on log data analysis is also given. All the procedures are numerically demonstrated through the process of analyzing actual log data collected from a game company.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.6
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• pp.244-257
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• 2017

Traffic congestion occurs from drivers' human factors such as driver reaction time, reckless lane change, and inexperienced driving. When Automated Vehicles are introduced, human factors are excluded, resulting in increased average vehicle speed, stabilizing traffic flow, and increasing road capacity. This study analyzed traffic flow changes through traffic volume-speed-density plots, and increased road capacity due to Automated Vehicles. As a result of the analysis, when rate of automated vehicles gests higher, the traffic flow became stable. Additionally, it was analyzed that when all vehicles were automated, the road capacity increased by about 120 %. It is expected that there will be a positive expectation in terms of traffic congestion and traffic demand management due to the introduction of Automated Vehicles.

• Convergence Security Journal
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• v.2 no.2
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• pp.89-97
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• 2002

We use the call routing to interpret the number or name for routing address in multimedia internet. The routing address is used for connection setup. The traffic engineering consists of traffic management, capacity management and network planning. In this paper, in the traffic management function, the basic functions for call routing and connection/bearer-path routing will be presented.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.3
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• pp.101-107
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• 2017

Demand for air transportation in Korea keeps increasing, and the number of airport operations also grows as a result. The major two airports in Korea, Incheon International Airport and Gimpo International Airport, share the metropolitan airspace, which is crowd with air traffic. As air traffic increases in the metropolitan airspace, the demand for the airport operations would outnumber the capacities of these airports. However, there is a room to efficiently manage the shortage of the airport capacity due to the different distributions of operations in these airports. This study presents a dynamic slot allocation that allows exchanging slots according to the traffic demand. The dynamic allocation mitigates the airports' capacity problem but the airspace capacity itself should be increased in order to tackle the problem fundamentally.

• Korean Management Science Review
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• v.16 no.1
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• pp.39-50
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• 1999

This paper proposes a new call admission control method to enhance the reverse link capacity of a cell with heavy traffic in the CDMA PCS system under the uneven traffic load between cells. Since the capacity of a cell in the CDMA system is restricted by the total interference caused by terminals in the own cell and the adjacent cells, we can enhance the capacity of a cell by reducing the interference from other cells if possible. Our power control method allows that the signal powers received in base stations with heavy traffic be larger than those received in base stations with light traffic in order to make the interference due to other cells in the cells with heavy traffic relatively small. In the previous study, it was assumed that the signal power received by each base station in the CDMA PCS system is same when the call admission control algorithm is implemented. We could show that the reverse link capacity of a cell in the CDMA PCS system can be increased about 20% under our call admission control method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.4B
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• pp.576-583
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• 2010

Wireless Internet is the network which provides wireless access in order to serve the Internet connections and data communication through the mobile handsets. To get efficient wireless access to the Internet, we need the WAP (Wireless Application Protocol) gateway that performs protocol translation and contents conversion between two different networks. We need the capacity dimensioning of the WAP gateway system in order to provide the wireless Internet service stably and cost-effectively. We also need the traffic engineering methods including traffic modelling and forecasting for the economical facility investment. The existing method of WAP gateway capacity dimensioning was intuitive and qualitative. But in this paper, we deal with the capacity dimensioning analytically and quantitatively on the basis of WAP traffic description parameters and traffic forecasting method.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.125-128
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• 2000

In this paper, we derive forward link Erlang capacity reflecting both outage probability and blocking probability of each traffic type in mixed traffics environment. We firstly determine the number of available virtual trunks of the forward link from a circuit switching perspective. Then, capacity sharing model and generalized Erlang model are employed to derive joint Erlang capacity of various traffics types.