• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.26 no.4
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• pp.14-21
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• 2012

This paper study a method of modeling and simulation of LED driver circuit for a design optimization. Simplified LED modeling is introduced and a driver IC, HV9910, is modeled by implementing the major function blocks. Circuit of buck type converter is constructed for simulation. Simulation includes not only the internal function of IC but also the various performance results such as LED array current control and dimming. Experiment results are also shown to prove the verification of its usage. This results show that the simulation approach is valid for a circuit optimization and a reduction of development time.

• Journal of the Korea Society for Simulation
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• v.10 no.3
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• pp.1-14
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• 2001

A hybrid system is defined as a mixture of continuous systems and discrete event systems. This paper first proposes a framework for hybrid systems modeling, called Hybrid Discrete Event System Specification (HDEVS) formalism. It then presents a method for simulators interoperation in which a continuous system simulator and a discrete event simulator are executed together in a cooperative manner. The formalism can specify a hybrid system in a way that a continuos system and a discrete event system are separately modeled by their own specification formalisms with a support of well-defined interface. We call such interface an A/E converter for analog-to- event conversion and an E/A converter for event-to-analog conversion. Simulators interoperation is based on the concept of pre-simulation in which simulation time for a continuous simulator is advanced in accordance with a discrete event simulator.

• The Transactions of the Korean Institute of Power Electronics
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• v.12 no.3
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• pp.213-220
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• 2007

As the equipments with the fast load characteristics become popular, a onboard generator should satisfy the fast response characteristics. This paper describes the modeling, simulation and experiment of the homo-polar generator developed for the fast load. The simulation model of a homo-polar generator with input limiter is developed, and the optimal gain to improve the response characteristics can be determined by simulation and analysis. The improved bandwidth and stability of the developed generator with optimal gain are verified by simulation and experiment.

• Journal of the military operations research society of Korea
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• v.26 no.2
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• pp.101-119
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• 2000

US DoD designated the High LEvel Architecture (HLA) as the standard technical architecture for all military simulation since 1996. HLA will supercede the current Distributed Interactive Simulation(DIS) and Aggregated LEvel Simulation Protocol(ALSP) methods by no funds for developing/modifying non-HLA compliant simulations. The new architecture specifies Rules which define relationships among federation components, an Objects Model Template which species the form which simulation elements are described, and an Interface Specification which describes the way simulations interact during operations. HLA is named as standard architecture in NATO, Australia and many other militaries. Also, it will be IEEE standard in the near future. It goes without saying that ROK military whose simulation models are almost from US must be prepared in areas such as ROK-US combined exercise, training, weapon system acquisition, interface models with C4I system, OPLAN analysis, operations, and os on. In this paper, we propose several effective alternatives and issues for ROK Defense Modeling and Simulation under the transition of new HLA architecture. Those include secure the kernel of new simulation technology and develop our own conceptual model, RTI software, prototype federation for each service and aggregated one. In order to challenge the new simulation architecture effectively, we should innovate our current defense modeling and simulation infrastructure such s manpower, organization, budget, research environment, relationships among academia and industry, and many others.

• Nuclear Engineering and Technology
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• v.49 no.2
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• pp.295-305
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• 2017

This paper reviews current status of the unified approach known as integrated safety assessment (ISA), as well as the associated SCAIS (simulation codes system for ISA) computer platform. These constitute a proposal, which is the result of collaborative action among the Nuclear Safety Council (CSN), University of Madrid (UPM), and NFQ Solutions S.L, aiming to allow independent regulatory verification of industry quantitative risk assessments. The content elaborates on discussions of the classical treatment of time in conventional probabilistic safety assessment (PSA) sequences and states important conclusions that can be used to avoid systematic and unacceptable underestimation of the failure exceedance frequencies. The unified ISA method meets this challenge by coupling deterministic and probabilistic mutual influences. The feasibility of the approach is illustrated with some examples of its application to a real size plant.

• Korean Journal of Computational Design and Engineering
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• v.17 no.2
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• pp.79-90
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• 2012

In digital virtual manufacturing simulation, Digital Human widely used to optimal workplace design, enhancing worker safety in the workplace, and improving product quality. However, the case of ergonomics simulation solutions to support digital human modeling, Optimal DHM (Digital Human Model) data needed to develop and perform DHM will collect information related to the production process. So simulation developer has burden of collecting information. In this study, to overcome the limitations of existing solutions, we proposed the ADAGIO(Automated Digital humAn model development for General assembly usIng Ontology) framework. The ADAGIO framework was developed for DHM ontology to support optimal deployment of digital virtual environment and in order to ensure consistency of simulation components that are required for simulation modeling was made of a library.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.115-117
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• 2012

Task based modeling is essential in a construction operation simulation modeling. It allows dealing with local variables or delay factors that affect productivity and improves the reusability of existing operation models. An operation model can secure reality only if it reflects the real construction processes by effectively dealing with zoning issue. However, system users have some difficulties in modeling a construction operation that is consisted of several processes having different production units. Zoning is a major modeling issue when the task based modeling method is implemented using the existing discrete event simulation systems. This paper highlights the difficulty and presents a new method that complements the zoning issues attributed to different production units. The method is described in detail by presenting the flow of entities. It is confirmed that the zoning method effectively deals with the unbalance of production units between processes and facilitates to model an operation model having processes with different production units. The "Zoning module" contributes to increasing accuracy of simulation result.

• ETRI Journal
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• v.31 no.6
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• pp.809-811
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• 2009

We propose a novel simulation method for modeling the game of golf using SystemC, a system description language that allows modeling of a concurrent system's behavior. Utilizing the proposed simulator, we compare different outing formats of golf, namely, regular and shotgun, in terms of playing time. Our simulation results reveal that the shotgun format can take longer than the regular format if the number of groups in a golf course exceeds 33 for the scenario we tested, confirming the belief that the shotgun format can take longer than the regular format. We also justify our simulation by comparing the simulation and analytical results.

• Journal of the Korean Society of Costume
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• v.57 no.2 s.111
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• pp.45-58
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• 2007

This study shows that clothes are made just the same as the real thing in the virtual space through 3D digital technology. This study is significant to expand the area of fashion design in the virtual space. This study analyzes the practical use of the third dimension computer graphics in the aspect of fashion, and it is proposed the 3D fashion design simulation in the virtual space used on 3D studio max, poser, photoshop program according to fashion design process. The main design concept is "temporary bridge" from rainbow. "Temporary bridge" is a rainbow bridge which connects nature, man and technology, and also the past, present, and future. This study is supposed six fashion design in accordance with three sub-theme under main concept by changing rotor and texture used on 3D simulation. The conclusion are as follows : First fashion design process, which consists of design conceptualization, design definition, and computer design process, composed of body modeling, clothing modeling, texture mapping, rendering by lighting and camera establishing are compared. Second, fashion design process is applied to digital technology. Third, the method of body modeling is both that of direct modeling in 3D Studio Max and that of importing DXF file from poser. And the method of direct clothing modeling in 3D Studio Max are two methods, polygon modeling and nurbs modeling. Polygon modeling is more satisfied than nurbs modeling in the aspect of expression to clothing and round face. Forth, this study applies textures and colors transformed by photoshop on manufactured 3D Clothes. According to this result, fashion designers are able to confirm a customer or client in their design minds viewing 3D simulation by various textures. colors and angles. It is able to advance digital fashion show in the future.

• Journal of Korean Society of Transportation
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• v.20 no.6
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• pp.151-152
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• 2002