• Journal of Navigation and Port Research
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• v.32 no.5
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• pp.369-377
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• 2008

Interest in high productivity and streamlined operation is growing amid a heated competition between ports and mega size vessel oriented operation. It becomes clear that terminals that operate YT(Yard Tractor) for transportation in container yard have less efficiency in operation and cost comparing terminals functioning AGV(Automated Guided Vehicle) system. To offset disadvantages arising out of YT operations, continual efforts (e,g YT pooling operation) were taken place for the last decade, but the result has not been fruitful; YT pooling operation still has a problem in that it cannot read individual YT's actual location. This study suggests 'YT dynamic operation model'- a practical application of RTLS(Real Time Location System) technology which will solve YT pooling operation problems.

• Journal of the Korean Society of Safety
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• v.11 no.2
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• pp.52-59
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• 1996

This paper presents a new approach for assessing the dynamic reliability in a complex system such as a nuclear power plant. The method is applied to a dynamic analysis of the potential accident sequences which may occur during mid-loop operation. Mid-loop operation is defined as an operation to make RCS water level below the top of the flow area of the hot legs at the junction with the reactor vessel for repairs and maintenance of steam generators and reactor coolant pumps for a specific time. The Idea behind this approach consists of both the use of the concept of the performance achievement/requirement correlation and of a dynamic event tree generation method. The assessment of the system reliability depends on the determination of both the required performance distribution and the achieved performance distribution. The quantified correlation between requirement and achievement represents a comparison between two competing variables. It is demonstrated that this method is easily applicable and flexible in that it can be applied to any kind of dynamic reliability problem.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.5
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• pp.625-633
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• 2021

This paper considers the development of safety operation guideline for onboard A-Frame system used to operate heavy-work ROV using dynamic simulation. Onboard A-Frame is affected by ship's behavior and large inertia by the marine environment. For this reason, safety operation guidelines are required for the safety of workers who operate ship-mounted equipment. In order to develop a guideline, it is necessary to evaluate the safety loads through real sea experiment. However, simulation method is used instead since it is difficult to conduct experiments in sea. Therefore, a procedure for safety operation analysis based on dynamic simulation that can consider ship behavior and marine environment and a safety operation table were proposed in this study. And the construction of safety operation table and guide for safety operation using the applied load and safety factor analysis results were considered.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.329-334
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• 2002

Preliminary test for the design and construction of a tuned dynamic absorber is a conducted. Proposed tuned dynamic absorber is a cantilevered beam type, and is supposed to adjust its natural frequency according to the changing operation condition of the primary system. The modal mass of the dynamic absorber is the easiest to control, therefore, the position of the attached mass of the dynamic absorber is considered as the main design parameter of the absorber. The effect of the dynamic absorber is experimentally verified under various operation conditions of the primary system.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.4
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• pp.15-21
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• 2002

This paper presents parallel operation of ZVT(Zero Voltage Transition) FUll Bridge Converter with Dynamic Current Shared Inductor. In the conventional method, CT(Current Transformer) have been used tn share the load current equally with converters. In this system, at parallel operation of ZVT Full Bridge Converter, dynamic current shared inductor divides the same current of unit converter and ZVT circuit aids to high efficiency. Superiority of the characteristics is verified through the experiment with a 2[㎾], 50[㎑] prototype converter.

• Journal of Korean Society of Transportation
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• v.30 no.1
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• pp.59-72
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• 2012

In aspects of traffic operation, a climbing lane may cause traffic congestion if the volume of traffic (v/c) grows and the ratio of heavy vehicle increases. Conversely, it would be effective, if the climbing lane is dynamically operated according to changes in traffic flow. However, there are no guideline to effectively control this climbing lane in aspects of traffic operation. In this study, we examine the necessity of flexible traffic operation criteria and its process for dynamic traffic management and also establish and analyze the effect of flexible traffic operation criteria in accordance with traffic properties using an example of climbing lane. We selected the operation criteria (critical travel speed), which decides whether to operate or close the climbing lane when the average travel speed of climbing lane is 50km/h based on VISSM (microscopic traffic simulation) analysis of Nakdong junction towards Masan with the volume of traffic (v/c), ratio of heavy vehicle as the traffic operation parameters. Based on the simulation result in accordance with the volume of traffic by the operation mode of climbing lane, the analysis on the effect of dynamic traffic management of climbing lane showed that the dynamic traffic management provides more convenience compare to the operation and close of climbing lane. Thereby, we proved that the dynamic traffic management of climbing lane is more effective.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.136.2-136.2
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• 2011

A dynamic simulation study on SCR process in GTL process was carried out in order to find optimum operation conditions for pilot plant operation. Optimum operating conditions for SCR synthesis gas process were determined by changing operation variables such as feed temperature and pressure. It was also assumed that physical properties of reaction medium were governed by RKS (Redlich-Kwong-Soave) equation. The effect of temperature and pressure on synthesis gas process $H_2$/CO ratio were mainly examined. Dynamic simulation results were fed back to feed operation condition for optimizing productivity, especially for appropriate condition to FT (Fischer-Tropsch) synthesis unit.

• Journal of the Korean Society of Industry Convergence
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• v.27 no.4_2
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• pp.943-951
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• 2024

This paper considers the simulation-based installation and operation safety analysis of installation and operation machinery of USBL as underwater equipment in operation environments. The simulation model of this mechanical system was developed using flexible multibody dynamics simulation technology. Operation and environmental conditions were applied using dynamic forces model considering ocean environments. The developed simulation model was used to evaluate operation safety through eigenvalue analysis, dynamic forces analysis, and structural analysis. As the analysis results, the operation safety was very low in extreme operation condition due to increase of dynamic loads by VIV effect. It was not a problem because safety factor had more than 2.0 in this case. However, the operation safety should be further strengthened because the USBL and LARS was installed and utilized in unmanned vessel with automatic controls. In order to improve safety by avoiding VIV frequency, we redesigned the USBL pole.

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.19-20
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• 2014

Boiler design should be desinged to maximize thermal efficiency of the system under imposed load requirement and a boiler should be validated for transient operation. If a proper prediction is possible on the transient behavior and transient characteristics of a boiler, one may asses the performance of boiler component, control logics and operation procedures. In this work, dynamic modeling method of boiler is presented and dynamic simulation of load runback scenario was carried out on suprecritical oil-firing boiler.

• Architectural research
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• v.19 no.3
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• pp.71-77
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• 2017

Dynamic pricing refers to a system in which a tariff varies, according to a level of charging and applied time depending on time change. The power billing system used in the Korean Electric Power Corporation (KEPCO) is based on time of use (TOU) pricing, which is one of the dynamic pricing systems. This paper aimed to determine the operational results of a variable refrigerant flow system, to which a new control algorithm was applied, in order to respond to dynamic pricing, in summer and the utility of the new control. To do this, real measured data was acquired from a VRF system installed in a building for educational purposes, where dynamic pricing was applied for about 100 days during summer time. At the maximum load operation time period in TOU, the new control minimized operation within the indoor comfort range, an increase in refrigerant evaporation temperature in the indoor unit and the number of revolutions in a compressor in the outdoor unit was limited. As a result, power usage was decreased by 11%, and the operational cost by 14.6%. Furthermore, measurement results using the Predicted Mean Vote (PMV) model, that represented satisfaction of thermal environment, showed that 82.8% to 90.4% of the occupants of the building were satisfied during operation when the new control was applied.