• 전기의세계
• /
• v.27 no.1
• /
• pp.35-44
• /
• 1978

In this paper the best way of servicing to the waiting guests at the Express Bus Terminal, is to determined by the computer simulation. The mathematical model for the waiting guests is formulated with the statistics data by researching the waiting lines of the guests at the guests at the specified Express Bus Terminal. The waiting phenomena is simulated using Monte Carlo method to decide the proper number of window and the time for servicing. Finally it present the way of the improvement of service with the good results of simulation.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.52 no.8
• /
• pp.342-347
• /
• 2003

The suspension insulators are subjected to harsh environment in service for a long time. Long term reliability of the insulators is required for both mechanical and electrical performances. We studied an analysing method to find out a deformation of brittle porcelain with a thermal expansion of simulation analysis and experimental results show that cement volume growths affect severely to b mechanical failure ageing.

• Health Policy and Management
• /
• v.23 no.2
• /
• pp.103-111
• /
• 2013

Seven diagnosis-related groups (DRGs) prospective payment system is going to expand to all hospitals including university hospitals this year. However there are few studies on the change of practice pattern under prospective payment system in the university hospital setting. So This study was intended to predict the practice pattern change after the introduction of 7 DRGs prospective payment system in a university hospital setting. To predict the change of practice pattern, this study used simulation technique. Five hundred and nineteen patients classified as 5 DRGs in a university hospital were selected for simulation. The change of practice pattern were predicted based on clinicians' opinion. We also predicted payment change by service items. Major findings of this study are as follows. First, the total medical payment was reduced by 14.4%. The drug payment change (8.8%) took most of total payment reduction. The followings are the change of treatment material cost (3.2%), the change of laboratory tests cost (1.8%), the change of room charge (0.5%), and other payment change (0.1%), respectively. Second, most of the reduction in total medical payment resulted from the decreased amount of medical services themselves. The transfer of medical services to outpatient setting took up only 4.9% of the total payment reduction. The change of unit price or composition took up 5.5% of the total payment reduction. In this study we found that it is possible to reduce the inpatient services through practice pattern change in university hospital setting. However, it needs to be careful to adjust DRG payment after the reduction of provided services, because most of reduction was not due to service transfer but to service volume reduction. It is desirable to utilize the saving from practice pattern change as incentive to improve quality of care.

• Atmosphere
• /
• v.25 no.2
• /
• pp.309-322
• /
• 2015

The objective of this study is to evaluate the impact of the high resolution topographies and landuses data on simulated meteorological variables (wind speed at 10 m, temperature at 2 m and relative humidity at 2 m) in WRF. We compare the results with WRF simulation using each resolution of the topographies and landuses, and with 37 AWS observation data on the Seoul metropolitan regions. According to results of using high-resolution topography, WRF model gives better topographical expression over domain. And we can separate more detail (Low intensity residential, high intensity residential, industrial or commercial) using high resolution landuses data. The result shows that simulated temperature and wind speed are generally higher than AWS observation data. However, simulation trend with temperature, wind speed, and relative humidity are similar to observation data. The reason for that is that the high precipitation event occurred in CASE 1 and 2. Temperature have correlation of 0.43~0.47 and standard deviation of $2.12{\sim}2.28^{\circ}C$ in CASE 1, while correlation of more than 0.8 and standard deviation of $3.05{\sim}3.18m\;s^{-1}$ in CASE 2. In case of wind speed, correlation have lower than 0.5 and Standard Deviation of $1.88{\sim}2.34m\;s^{-1}$ in CASE 1 and 2. In statistical analysis shows that using highest resolution (U01) results are more close to the AWS observation data. It can be concluded that the topographies and landuses are important factor that affect model simulation. However, the tendency to always use high resolution topographies and landuses data appears to be unjustified, and optimal solution depends on the combination of scale effect and mechanisms of dynamic models.

• The KIPS Transactions:PartA
• /
• v.9A no.3
• /
• pp.317-326
• /
• 2002

The mobile telecommunication system has been growing exponentially after 1990s due to the high population in a city and the growth of mobile user. In this time, the current mobile system mainly concentrates on the voice communication. However, in the next generation, mobile users want to get very diverse services via mobile terminal such as the Internet access, web access, multimedia communication, and etc. For this reason, the next generation system, such as the UMTS system, has to support the packet data service and it will play the major role in the system. In different from the voice service, the packet data service should store packet data in a buffer at base station before it forwards. Consequently, the performance closely related to the buffer management and its operation. However, until now, there are rare study on the buffer behavior and management. In this paper, we will observe the buffer behavior in the UMTS systems by using simulation and analyze the results. For this research, we generate packet data traffics and model the UMTS system for a simulation. Then we analyze the buffer state by a simulation and calculate the buffer overflow probability by mathematical methods.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.21 no.6
• /
• pp.70-86
• /
• 2022

An autonomous demand-responsive bus with mobility-on-demand service is an innovative transport compensating for the disadvantages of an autonomous bus and a demand-responsive bus with mobility-on-demand service. However, less attention has been paid to the quantitative impact assessment of the autonomous demand-responsive bus due to the technological complexity of the autonomous demand-responsive bus. This study simulates autonomous demand-responsive bus trips by reinforcement learning on a microscopic traffic simulation to quantify the impact of the autonomous demand-responsive bus. The Chungju campus of the Korea National University of Transportation is selected as a testbed. Simulation results show that the introduction of the autonomous demand-responsive bus can reduce the wait time of passengers, average control delay, and increase the traffic speed compared to the results with fixed route bus service. This study contributes to the quantitative evaluation of the autonomous demand-responsive bus.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
• /
• v.8 no.1
• /
• pp.867-874
• /
• 2018

This study aims to develop a sort of expert system to simulate Internet of Things (IoT) service in architectural design alternatives and enhance the simulation performance using building information. The proposed protype system, named iotBIM, visualizes human behaviors and IoT services in a virtual place that is automatically generated from among design alternatives. We use commercial building information modeling (BIM) authoring tool for the development of iotBIM. The decision to develop iotBIM on the BIM platform was made because BIM tools already generate precise 3D models of design alternatives; iotBIM is plugged into the BIM tool as a simulation module. In the midst of the design process, architectural designers can activate iotBIM to investigate and establish IoT services that accord visually with design alternatives. The purpose of this study is to provide a theoretical and technological basis for the ultimate goal of this study.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2022.06a
• /
• pp.306-307
• /
• 2022

Recently, in the process of developing, verifying, and upgrading the e-Navigation service and autonomous navigation system, there is an increasing demand for inter-working with a ship-handling simulator that can simulate actual maritime traffic conditions. In this paper, to develop a ship-handling simulation system based on actual maritime traffic conditions, a simulation server was built, received information on the actual maritime traffic conditions from the e-Navigation linkage system, and changed to information for operating the ship-handling simulator. In order to provide simulation images to users, 3D shape modeling for trade ports, coastal ports in Korea and major type of ship were performed. The developed system will be used for the advancement of e-Navigation service, development and verification of autonomous navigation systems, by enabling simultaneous processing of more than 10,000 ships and allowing users to simulate actual maritime traffic conditions in the desired area.

• The Magazine for Energy Service Companies
• /
• s.84
• /
• pp.30-33
• /
• 2013

• Journal of the Korean Regional Science Association
• /
• v.10 no.1
• /
• pp.127-135
• /
• 1994