• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.20 no.7
• /
• pp.1-5
• /
• 2006

Fixed lighting of public ways for both drivers and pedestrians can create a nighttime environment in which people can see comfortably and can quickly and accurately identify objects on the roadway being travelled. Roadway lighting can improve traffic safety, achieve efficient traffic movement and promote the general use of the facility during darkness. The design of a roadway lighting system involves consideration of visibility, economics, esthetics, safety and environmental conditions. This paper shows estimation of horizontal illuminance and uniformity ratio by actual measurement of roadway lighting at main streets in Jejusi and evaluation of Jejusi roadway lighting conditions for modeling by computer simulation.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.41 no.4
• /
• pp.305-313
• /
• 2013

This paper presents a simulation system for air traffic control (ATC) training. The structure of the ATC is analyzed to define simulation components to be developed. Requirements that must be satisfied by a training simulator are also identified. The results were reflected in the design of the simulator. The training simulator is composed of three modules same as in real life : air traffic controller, aircraft, radar. Each developed module performs the strict unit tests and combine test based on the scalability, ease, real-time, the operating range of the algorithm derived from the requirements. The simulation system can be connected to an actual ATC, and used to validate the ATC system. At peak load, 1200 aircraft and 30 radars can be operated simultaneously.

• IE interfaces
• /
• v.14 no.2
• /
• pp.148-157
• /
• 2001

This paper considers a network restoration algorithm for all-optical WDM networks. As the increasing traffic and transmission speed, any failure on the networks will lead to loss of huge data and disruption of the services. Therefore, a network restoration algorithm is necessary for the high-speed all-optical networks. This paper suggests a distributed restoration algorithm for line or channel level failures under the dynamic rerouting. For the algorithm, some measures for performance evaluation are explicitly derived and simulation studies are exploited to evaluate its usability by SLAM(Simulation Language for Alternative Modeling) II.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.16 no.4
• /
• pp.407-414
• /
• 2010

The fairway within the area of Yul-do and Songdo located near the Myeongnyang-sudo approaches south of Mokpo harbor is well guided by traffic separation scheme and other navigational aids. However, that part of the waterways where Yul-do is located sits at the cross-roads of marine traffic and is subjected to some potential risks in the voyage navigation: the effect of climatic phenomenon, the disregard of most ships in using the western sector of the fairway creating a congestion in the eastern sector, and lastly, the disadvantageous erect of the location and height of Yul-do island that hinders good lookout. This study investigates the environmental conditions that prevailed in the area in the span of 5-year period and the marine traffic situation taken from the data within the 72-hour period The navigational hazards and marine casualties are also be presented. The results are analyzed and are made the basis of a proposal for an improved separation of traffic. Thereafter, an evaluation is carried out by using the components of marine traffic flow simulation and ES modeling index. It is evaluated through simulation by the use of full-mission ship handling simulator.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.8
• /
• pp.2106-2119
• /
• 1997

NDAS(Network Data Access System) is a system that interconnects high speed network(B-ISDN) and Local Area Network(Ethernet, FDDI). Nowadays, the request of multimedia data increases rapidly, so NDAS system must accept and process that request efficiently. Comparing with normal data traffic characteristics, multimedia data traffic characteristics are much complex, so it is necessary to implement the system that can cover such factor. In this paper, we suggest a NDAS hardware system model and also we propose a proper buffer size of NDAS system through the simulation. For measuring the proper buffer size of NDAS, we assumed two different simulation models, one is the case of using only one buffer and the other is the case of using two different buffers for Ethernet and FDDI, respectively. After comparing and analyzing simulation results, we suggest the proper NDAS system buffer size.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.17 no.3
• /
• pp.43-53
• /
• 2007

Internet becomes more and more popular, and most companies and institutes use web services for e-business and many other purposes. With the explosion of Internet, the occurrence of cyber terrorism has grown very rapidly. Simulation is one of the most widely used method to study internet worms. But, it is quite challenging to simulate very large-scale worm attacks because of various reasons. In this paper, we propose a hybrid modeling method for RCS(Random Constant Spreading) worm simulation. The proposed hybrid model simulates worm attacks by synchronizing modeling network and packet network. So, this model will be both detailed enough to generate realistic packet traffic, and efficient enough to model a worm spreading through the Internet. Moreover, our model have the capability of dynamic updates of the modeling parameters. Finally, we simulate the hybrid model with the CodeRed worm to show validity of our proposed model for RCS worm simulation.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2004.04a
• /
• pp.367-374
• /
• 2004

Roads which were not considered conditions such as capacity of the traffic have made seriously traffic problems and complex road lines. Construction of new roads have to make efficiently for solving the above problems and gain benefits. Simulation using 3D-GIS help find a matter of the design and do understanding users who work In the practical businesses. This study is showed selection of the optimal road line based on 3D-GIS through the traffic modeling.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.24 no.3
• /
• pp.83-91
• /
• 1999

In order to build and manage an ATM network effectively under several types of control methods, it is necessary to estimate the performance of the equipments in various viewpoints, especially of ATM multiplexer. As for the method to model the input stream into the ATM multiplexer, many researches have been done to characterize it by, such as, fluid flow, MMPP(Markov Modulated Poisson Process), or MMDP (Markov Modulated Deterministic Process). We introduce an MRP(Markov Renewal Process) to model the input stream which has proper structure to represent the burst traffic with high correlation. In this paper, we build a model for aggregated heterogeneous ON-OFF sources of ATM traffic by MRP. We make discrete time MR/D/1/B queueing system, whose input process is the superposed MRP and present a performance analysis by finding CLP(Cell Loss Probability). A simulation is done to validate our algorithm.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2014.10a
• /
• pp.948-951
• /
• 2014

Road traffic noise is closely related with urban forms and urban components, such as population, building, traffic and land-use, etc. Hence, it is possible to minimize the noise exposure problem depending on how to plan new town or urban planning alteration. This paper provides ways to apply for urban planning in consideration of noise through exposed noise estimation for urban planning alteration. Spatial autoregressive model which explains about 81.4% of road traffic noise from the former paper is used. The simulation results by the spatial statistical model are compared with those by the engineering program-based modeling for 5 small-scaled scenarios of urban planning alteration. The error from the limitation of containing informations inside the grid cell and the difficulties of reflecting acoustic phenomena is existed. Nevertheless, in the stage of preliminary design, the use of the statistical models that have been estimated well is useful in time and economically.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.2
• /
• pp.277-282
• /
• 2005

The arrangement of I-picture starting times of multiplexed variable bit .ate (VBR) MPEG videos may significantly affect the cell loss ratio (CLR) characteristics of the multiplexed traffic. This paper presents an efficient I-picture arrangement method which can minimize the CLR of the multiplexed traffic when multiple VBR MPEG videos are multiplexed onto a single constant bit rate link. In the proposed method, we use the probability that the arrival rate exceeds the link capacity as the measure for the CLR of the multiplexed traffic. Simulation results show that the proposed method can find more optimal arrangement than existing methods in respect of the CLR.