• Journal of the Korean Institute of Telematics and Electronics A
• /
• v.33A no.7
• /
• pp.198-204
• /
• 1996

Electron beam lithography is one of the importnat technologies which can delineate deep submicron patterns. REcently, electron beam lithography is being applied in delineating the critical layers of semiconductor device fabrication. In this paper, we present a development simulation program for electron beam lithography and study the development profiles of resist when resist is exposed by the electron beam. Experimentally, the development parameter of positive and negative resists are measured and the data is applied to input parameter of the simulation program. Also simulation results are compared of the process results in the view of resist profiles. As a result, for PMMA and SAL 601 resist, the trend of simulation to the values of process parameters agree with real process results very well, so that the process results can be predicted by the simulation.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2005.05a
• /
• pp.1033-1039
• /
• 2005

Parallel and distributed simulation is concerned with the efficient execution of large-scale discrete event simulation models on multiprocessors and distributed platforms. After the development of WWW, many efforts in the parallel and distributed simulation have been made for modeling, particularly building simulation languages and creating model libraries that can be assembled and executed over WWW. However, web-based parallel and distributed simulation is restricted by heterogeneous computing environments. Recently, the advent of XML and web services technology has made these efforts enter upon a new phase. Especially, the web services as a distributed information technology have demonstrated powerful capabilities for scalable interoperation of heterogeneous systems. This paper aims to develop and evaluate the parallel and distributed simulation using the web services technology. In particular, a prototype multi-pass simulation framework is implemented using Java-based web services technology. It focuses on the efficiency of multi-pass simulation used for optimization through the distribution of simulation replication to several simulation service providers. The development of parallel and distributed simulation using web services will help solve efficiently large-scale problems and also guarantee interoperability among heterogeneous networked systems.

• Journal of the Korea Society for Simulation
• /
• v.20 no.1
• /
• pp.9-18
• /
• 2011

Recently, in the era of low carbon and green growth, the importance of railway transportation is being emphasized However, there is a lack of research on simulation for railway depot. This paper presents the development of the dynamic simulator for LRT(Light Rail Transit) depot. This study presents explanations of requirement analysis, architecture, database design, simulation algorithm, and design and development of the simulation tool. The dynamic LRT depot simulation tool consists of four modules; a Network Editor to create and modify information regarding railroad, train, signal, turnout, job and station, a Simulator to calculate train movement algorithm, a Reporter to show simulation results in table and graphs, and an Animator to animate simulation results dynamically. It is hoped that this study on general details of structure, design and development of LRT depot dynamic simulator will perform as a good reference to future development of new simulation tools.

• Journal of the Korea Society for Simulation
• /
• v.22 no.4
• /
• pp.29-38
• /
• 2013

Modeling and simulation technology is being used in various fields. Especially in the field of military, Simulation-Based Acquisition (SBA) is recognized as a essential policy. To effectively carry out SBA, modeling and simulation techniques should be applied in the whole life-cycle for the weapon system development, and the framework and tools which can help the rapid component development and reusability are needed. In this research, we use the simulation framework based on modeling formalism for enhancement of reusability and a GUI-based modeling environment for rapid M&S component development. The Proposed framework can act as plug-in components on the basis of XML-based object model, so that the flexible design is possible for the change of the model and simulation structure. In addition, our methods are effective to implement the functions for supporting simulation such as the model data logging and communication with external systems. In this paper, we describe an architecture and functions for the framework and tools.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2008.04a
• /
• pp.442-445
• /
• 2008

The purpose of this study is making Proto-type development of BIM based Architectural Construction Simulation System. This study suggest a new schedule access method for overcoming limitation of current Simulation Program focused on visualization. The method made from analysis of current Simulation Program. This program is based on Visual Basic .Net language.

• Proceedings of the KIEE Conference
• /
• 1993.07a
• /
• pp.421-423
• /
• 1993

A real time simulation is an effective tool for use in design, performance evaluation, and testing of the vehicle dynamic system. An alternate approach is to use a computer system designed specifically to provide an integrated simulation environment in which all aspects of hardware-in-the-loop simulation task have been taken into account.

• Proceedings of the Korea Society for Simulation Conference
• /
• 2001.10a
• /
• pp.444-449
• /
• 2001

There have been many accidents of passenger ships on the sea and they have caused a big loss of human lives. Maritime Safety Committee(MSC) of International Maritime Organization(IMO) made evacuation analysis of Ro-Ro passenger ships mandatory in order to save as many lives as possible at the time of accident. But this is a temporary regulation and HSC/IMO ties to introduce a performance-based regulation to improve the effect of regulation. Simulation-based evacuation analysis is the basis of performance-based regulation. In this paper, we performed a simulation-based evacuation analysis on a passenger ship, which is usually used in the plying between land and islands in Korea, with EXODUS system. Through inspecting the results from this analysis in more detail, we can make a proposal to improve the safety of passenger ship. Finally we describe the features of IMEX(Intelligent Model for Extrication Simulation), a new evacuation model being developed in KRISO.

• Korean Chemical Engineering Research
• /
• v.51 no.1
• /
• pp.10-24
• /
• 2013

The state-of-arts of multiscale simulation (MSS) in science and engineering is briefly presented and MSS for process development (PD-MSS) is proposed to effectively apply the MSS to the process development. The four-level PD-MSS is composed of PLS (process-level simulation), FLS (fluid-level simulation), mFLS (microfluid-level simulation) and MLS (molecular-level simulation). Characteristics and methods of each level, as well as connectivity between the four levels are described. For example in PD-MSS, absorption column, fluidized-bed reactor, and adsorption process are introduced. For successful MSS, it is necessary to understand the multiscale nature in chemical engineering problems, to develop models representing physical phenomena at each scale and between scales, to develop softwares implementing mathematical models on computer, and to have strong computing facilities. MSS should be performed within acceptable accuracy of simulation results, available computation capacity, and reasonable efficiency of calculation. Macroscopic and microscopic scale simulations have been developed relatively well but mesoscale simulation shows a bottleneck in MSS. Therefore, advances on mesoscale models and simulation tools are required to accurately and reliably predict physical phenomena. PD-MSS will find its way into a sustainable technology being able to shorten the duration and to reduce the cost for process development.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.22 no.4
• /
• pp.536-544
• /
• 2019

During the assembly and function inspection of missile system, flight simulation process is required. In the conventional flight simulation check of missiles, an inertial navigation system simulator was used to transmit the navigation output data acquired in HILS. There are several disadvantages in terms of check configuration complexity and data synchronization when using the simulator. So we proposed a new flight simulation method that utilizes the nonvolatile built-in memory of the aviation control unit. The data processing procedure and operation procedure of the proposed method for type I and type II missiles are presented. And we analyzed the causes of the difference between proposed method result and the HILS result for type II missile. By comparing the results obtained by the experiments using the proposed method with the results of HILS, the validity of proposed method was confirmed.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.25 no.4
• /
• pp.412-424
• /
• 2022

Since traditional derivative-based optimization for noisy simulation shows bad performance, evolutionary algorithms are considered as substitutes. Especially in case when outputs are binary, more simulation trials are needed to get near-optimal solution since the outputs are discrete and have high and heterogeneous variance. In this paper, we propose a genetic algorithm called SARAGA which adopts dynamic resampling and fitness approximation using surrogate. SARAGA reduces unnecessary numbers of expensive simulations to estimate success probabilities estimated from binary simulation outputs. SARAGA allocates number of samples to each solution dynamically and sometimes approximates the fitness without additional expensive experiments. Experimental results show that this novel approach is effective and proper hyper parameter choice of surrogate and resampling can improve the performance of algorithm.