• Proceedings of the KIEE Conference
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• 2005.10b
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• pp.231-233
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• 2005

For the low-power design of the mobile multimedia system architecture, this paper modeling the mobile multimedia system and analysis the power consumption profile about the whole communication environment. The mobile system model consist of air interface, RIP front-end, base-band processing module and human interface. For the result of power consumption profile analysis, the power consumption of multimedia processing is above 60% compare to the whole power consumption in mobile multimedia system. To minimize the power consumption in processing module which consumes the large power, this paper proposed the Microscopic DVS technique which applies the optimum voltage for the each multimedia frame. For the simulation result, proposed power minimization technique reduce the power consumption about 30%.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.17 no.5
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• pp.14-28
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• 2018

Thanks to technical improvement on the vehicle to vehicle communication and the intelligent transportation system, gradual introduction of the autonomous vehicles is expected soon in the market. The study analyzes the autonomous vehicles' impacts on the network efficiencies. In order to measure the network efficiencies, the study applies the sequential procedures that combines the microscopic and macroscopic simulations. The microscopic simulation attends to the capacity changes due to the autonomous vehicles' proportions on the roadway while the macroscopic simulation utilizes the simulation results in order to identify the network-wide improvement. As expected, the autonomous vehicles efficiently utilizes the existing capacity of the roadway than the human driving does. Particularly, the maximum capacity improvements are expected by the 190.5% on the expressway. The significant capacity change is observed when the autonomous vehicles' proportions are about 80% or more. These improvements are translated into the macroscopic model, which also yields overall network efficiency improvement by the autonomous vehicles' penetration. However, the study identifies that the market debut of the autonomous vehicles does not promise the free flow condition, which implies the possible needs of the system optimal routing scheme for the era of the autonomous vehicles.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.1
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• pp.251-259
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• 2013

This paper is aimed to introduce to a moving bollard (i.e., smart bollard) to improve the pedestrian safety along the crosswalk in the school zone as a means to physically separate pedestrians and approaching vehicles, to propose the appropriate criteria for its installation and implementation from the traffic engineering perspective, and to evaluate its effectiveness with the microscopic simulation model. The simulation results indicate that implementing the smart bollard results in the decrease of average approaching speed and traffic throughput and the most critical factors affecting its effectiveness are yellow time of the traffic signal directly associated with the location of the advance warning sign and its operation time, 5~6 seconds and 2~3 seconds, respectively.

• Journal of Korean Society of Transportation
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• v.22 no.2 s.73
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• pp.95-102
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• 2004

The COSMOS is an adaptive traffic control systems that can adjust signal timing parameters in response to various traffic conditions. To evaluate the performance of the COSMOS systems, the field study is only practical option because any evaluation tools are not available. To overcome this limitation, a newly integrated interfacing simulator between a microscopic simulation program and COSMOS was developed. In this paper, a detector module and a signal timing module as well as general feature of the simulator were described. A validation test was performed to verify the accuracy of the data flow within the simulator. It was shown that the accuracy level of information from the simulator was high enough for real application. Several practical comments on further studies were also included to enhance the functional specifications of the simulator.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.4
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• pp.63-77
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• 2023

This study applies reinforcement learning to effectively operate expressway hard shoulder running (HSR). An HSR algorithm was developed, and its effectiveness was evaluated using the VISSIM microscopic simulation program. The simulation evaluated two aspects: mobility and safety. The DQN-based HSR algorithm found speed improvement of up to 26 km/h. Compared to the current method, the difference in the number of conflicts was not significant. Considering the results, a DQN-based HSR operation has a clear effect, and it is necessary to consider adjusting the current operational criteria.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.27 no.1
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• pp.20-25
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• 2019

To prepare for the ever-increasing demand for air transport, airport operators should be well aware of the timing of the saturation of the facility and increase the capacity of the airport through extension or extension. The capacity of an airport is determined by the smallest value of the facilities that make up the airport, but it is generally customary to determine the capacity of the costly and time-consuming runway as a whole for the airport. For analyzing the capacity of the runway capacity, the study used the most accurate microscopic air traffic simulation, Simmod-PRO, to analyze the saturation time of three runways currently in Incheon International Airport's operation, and calculate the appropriate time for operation of the 4th runway. The study also calculate the relocation of Airport's high-speed exit taxiway for analyzing the increasing of capacity.

• 한국전산유체공학회:학술대회논문집
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• 2003.10a
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• pp.268-269
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• 2003

The Boltzmann kinetic equation is solved directly by means of the conservative splitting method. Underexpanded supersonic free jet flows with small Knudsen numbers are studied. In this numerical simulation features intrinsic to appropriate experiments are observed. Streamwise vortices in a mixing layer and chaotic downstream temporal-spatial fluctuations of microscopic quantities with large amplitude are obtained.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.493-495
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• 2005

The director profiles of the Bloch walls are directly visualized using fluorescence confocal polarizing microscopy. Both pure twist Bloch walls and diffuse Bloch walls are analyzed. Polar anchoring energy was measured from optical simulation of the transmitted light interference pattern or the fluorescence intensity profile of a pure twist wall..

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.789-792
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• 1993

We have proposed a fuzzy model for behavior of vehicles in the road traffic simulation system with microscopic model for analyzing traffic jam in the broad areas. It can exactly simulate each vehicle's behavior. We propose a new hardware processor to simulate fuzzy decision-making mechanism for its model. This paper describes the functions, performance and structure of the hardware processor.

• Journal of Korean Society of Transportation
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• v.10 no.3
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• pp.75-102
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• 1992

지난 수십년간 수많은 신호교차로제어모형이 제시되어 왔으나 과포화교차로를 특별히 다루는 기법은 거의 없었다. 본고에서는 과포화상태의 신호교차로제어를 위한 최적화모형이 제시된다. 지체도최소화나 연동폭최대화가 전통적인 제어목표로 사용되어 왔으나 혼잡교차로 제어에는 생산성최대화(maximum productivity)가 적절하며 본 모형에 사용되었다. 제시된 최적화모형은 Mixed Integer Linear Programming의 형태를 취한다. 본 모형은 두 개의 교차로 문제에 적용되었으며, 모형화 과정에 사용된 가정들의 적절함이 민감도분석에 의해 증명되었다. 최적해의 검증을 위하여 microscopic simulation model인 TRAF-NETSIM을 사용하였다.