• Journal of applied mathematics & informatics
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• v.9 no.2
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• pp.879-890
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• 2002

In this paper we consider open queueing system with a Poisson arrival process which have a finite upper bound on the arrival rate for which the system is stable. Interpolation approximations for quantities of interest, such as moments of the sojourn time distribution, have previously been developed for such systems, utilizing exact light and heavy traffic limits. These limits cannot always be easily computed for complex systems. Thus we consider an interpolation approximation where all of the relevant information is estimated via simulation. We show that all the relevant information can in fact be simultaneously estimated in a single regenerative simulation at any arrival rate. In addition to light and heavy traffic limits, both the quantity of interest and its derivative (with respect to the arrival rate) are estimated at the arrival rate of the simulation. All of the estimates are then combined, using a least squares procedure, to provide an interpolation approximation.

• Proceedings of the KOR-KST Conference
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• 1999.10a
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• pp.47-52
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• 1999

The methods currently in use to evaluate traffic impacts on the transportation network involve some fundamental shortcomings. First, the methodss do not properly take into account regional and local traffic impacts on the transportation network simultaneously. Second, temporal distribution of traffic, a major contributor to transportation problems, is not accurately accounted for. Third, traffic impact studies require costly and labor-intensive efforts to collect necessary data and to establish to collect necessary data and to establish traffic impact models. In this research, a new method called AMIS is developed for congestion management, access control, and impact simulation to overcome the shortcomings involved in the current methods. The new method is designed for a variety of scenarios such as access management strategies, land use policies, traffic impacts, and other congestion management strategies. This method can effectively be used, with little modification, anywhere in the United States. It is an improvement over the current traffic impact simulation methods that produces more reliable and accurate traffic impact estimates. The case studies conducted in this research have offered evidence that the new method, AMIS, is a credible congestion management tool. Most importantly, a case study presented in this paper illustrates how the new method can be used not only to estimate regional and local impacts of alternate supply management policies in the course of a day, but virtually on an hour-by-hour basis.

• Journal of Advanced Navigation Technology
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• v.18 no.2
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• pp.114-120
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• 2014

In this paper, we reviews the need and contents of aerodrome control simulator for air traffic controllers' training. In the view of managing the aviation safety, the departure and landing phases of aircraft are very important, because more than 60% of aircraft accidents and incidents have occurred in the take-off and landing phases. According to the benchmark each as practice type, simulation device and fidelity of reality of the air traffic control simulator, we have evaluated the implementation level of the domestic air traffic control simulator and checked up the current simulator's problems through the air traffic controllers' survey. Therefore, we suggest to the direction of developing a HI-FI simulator for aerodrome controllers.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.1231-1234
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• 2005

For the purpose of objective and scientific inspection, traffic accidents should be appraised and inspected by righteous material evidences, computer simulation, and studies such as automobile engineering, traveling and collision accident dynamics, road and traffic engineering. In this paper, it displays the results of studying cases with the reasons of traffic accidents by analyzing and studying automobile kinetics, real traffic accidents and the results of in scientific and objective ways. In this paper, it is proved that with compared by dry and wet road surface condition, the transient brake time of wet condition is longer than dry road condition. Moreover, compared with unpacked road condition and packed road condition. unpacked road condition is shorter than packed road condition using computer simulation.

• Journal of Korean Port Research
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• v.14 no.1
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• pp.27-35
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• 2000

In Pusan Harbour, new port development projects are implemented such as the Extended Terminal adjacent to the Gamman Terminal, Pusan New Port, the Navy $\bigcirc$$\bigcirc$ piers, etc. which will require new marine traffic environments in the Passage I of Pusan Harbour. Specially, the turning basin of the Extended Terminal adjacent to the Gamman Terminal has been designed to overlay the Passage I of Pusan Harbour, which will interrupt the inbound traffic flow and the results will be worried to decrease the efficiency of port operation. Therefore, this paper will be aimed to evaluate the traffic congestion in the Pusan Passage I due to the opening of new ports within Pusan Harbour in 2006 and 2011 by using computer simulation based the queueing theory.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.267-271
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• 2000

Traffic analysis during past years used the Poisson distribution or Markov model, assuming an exponential distribution of packet queue arrival. Recent studies, however, have shown aperiodic and burst characteristics of network traffics. Such characteristics of data traffic enable the scalability of network, QoS, optimized design, when we analyze new traffic model having a self-similar characteristic. This paper analyzes the self-similar characteristics of a small-scale mixed traffic in a network simulation, the real network Traffic.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.6
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• pp.23-32
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• 1996

This paper proposes a new buffer management scheme to service delay-sensitive traffic and loss-sensitive traffic fairly in ATM networks. The proposed scheme uses tow buffers for delay-sensitive traffic and loss-sensitive traffic. To satisfy the average delay time of delay-sensitive traffic, cells in real-time buffer are served first. When congestion occurs in nonreal-time buffer, low loss priority cell in real-time buffer can be pushed out by high loss priority cell in nonreal-time buffer can be transferred to real-time buffer considering threshold value in real-time buffer. Using computer simulation, the existing methods and proposed scheme are compared and analyzed with respect to cell loss rate and average delay time. Simulation results show that the proposed scheme have superior performance to conventional schemes.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.5A
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• pp.651-659
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• 2000

In this paper, a computer simulation approach is proposed to analyze the performance of reverse traffic channels in a base station serving voice and data calls in CDMA cellular systems. It is assumed that multiple traffic channels simultaneously serve a data call and a voice call is served by one traffic channel in a base station. The numerical examples will be presented to derive the capacity of traffic channels from the parameters such as the arrival rates and mean durations of voice and data calls, the soft handoff area ratio, etc..

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.505-508
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• 2000

We discuss simulation results concerning the performance of the TCP protocol when running over high-speed HFC networks. Hybrid Fiber Coaxial are likely to provide fast and cost effective sup-port to a variety of applications including Video on demand, interactive computer games, and internet-type applications such as Webbrowsing, ftp, and telephony. Since most of these applications, use TCP as the transport later protocol, the key to their success largely depends on the effectiveness of the TCP protocol. In all simulation scenarios the TCP traffic is maxed with some background traffic whose level is taken as a variable parameter. Both the background traffic and TCP traffic are either unshaped, or shaped according to the GCRA algorithm. The effect of the background traffic on the TCP protocol performance is discussed varying the buffering capacity with nodes as well as the peak bit rate that each TCP connection is allowed to use.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2956-2958
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• 2000

This paper describes the design of a real time traffic data acquisition system using loop detector and piezzo sensor. Loop detector is the cheapest method to measure the speed and piezzo is used to detect the vehicle axle information. A ISA slot based I/O board is designed for data acquisition and PC process the raw traffic data and transfer the data to the host system. Simulation kit is designed with toy car kits. simulated loop detector and piezzo sensor. The data acquisition system collects up to 10 lane highway traffic data such as vehicle count. speed. length axle count. distance between the axles. The data is processed to generate traffic count, vehicle classification, which are to be used for ITS. The system architecture and simulation data is included and the system will be tested for field operation.