• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.1059-1062
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• 1995

In cutting system, relative displacement between rool and workpiece is very important. Even though there have been so many works for modeling cutting process of end-milling, most of them have considered only one displacement of either tool or workpiece instead of both. In this paper, the relative displacement between tool and workpiece is considered for modeling cutting process of end-milling using simple experimental modal analysis and cutting force simulation program is developed. In cutting force model, instantaneous uncut chip thickness model is used and Runge-Kutta method is used for the simulation of time varying cutting system.

• 한국시뮬레이션학회논문지
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• 제14권4호
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• pp.55-68
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• 2005

The advancement in semiconductor technology is leading toward smaller critical dimension designs and larger wafer manufactures. Due to such phenomena, semiconductor industry is in need of an accurate control of the process. Photolithography is one of the key processes where the pattern of each layer is formed. In this process, precise superposition of the current layer to the previous layer is critical. Therefore overlay parameters of the semiconductor photolithography process is targeted for this research. The complex relationship among the input parameters and the output metrologies is difficult to understand and harder yet to model. Because of the superiority in modeling multi-nonlinear relationships, neural networks is used for the simulator modeling. For training the neural networks, conjugate gradient method is employed. An experiment is performed to evaluate the performance among the proposed neural network simulator, stepwise regression model, and the currently practiced prediction model from the test site.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2011년도 춘계학술대회
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• pp.329-338
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• 2011

Business processes are often of long duration, and include internal worker's decision making, which makes business processes to be exposed to many exceptional situations. These properties of business processes makes it difficult to design processes to support uncertainties from internal or external environments. The behavioral properties of business processes mainly depends on the data aspects of business processes. To formalize the data aspect of process modeling, this paper proposes a graph-based model, called Data Dependency Graph (DDG), constructed from dependency relationships specified between business data. The paper also defines a mechanism of describing a set of mapping rules that generates a process model semantically equivalent to a DDG, which is accomplished by allocating data dependencies to component activities.

• 대한전기학회논문지
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• 제38권3호
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• pp.237-246
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• 1989

A sliding memory covariance circular lattice (SMC-CL) filter and an efficient ARMA modeling method using the SMC-CL filter are presented. At first, SMC-CL filter is derived based on the geometric approach. Then ARMA process is converted into 2 channel AR process, and SMC-CL filter is applied to it. The structure of SMC-CL filter becomes simpler in case of ARMA modeling due to the whiteness of a driving input process. The parameters of ARMR process can be obtained by the Levinson recursions from the PARCOR coefficients of the second channel of the filter. Computer simulations are performed to show the effctiveness of the proposed algorithm.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.201-204
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• 2001

In this paper, for modeling of electrical characteristics in Poly Silicon Thin Film Transistors with process parameters set up optimum values. So, the I-V characteristics of poly silicon TFT parameters are examined and simulated in terms of the variations in process parameter. And these results compared and analyzed simulation values with examination value. The simulation program for characteristic analysis used SUPREM IV for processing, Matlab for modeling by mathematics, and SPICE for electric characteristic of devices. Input parameter for simulation characteristics is like condition of device process sequence, these electric characteristic of I$_{D}$-V$_{D}$, I$_{D}$-V$_{G}$, variations of grain size. The Gate oxide thickness of poly silicon are showed similar results between real device characteristics and simulation characteristics.ristics.

• 한국멀티미디어학회논문지
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• 제18권1호
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• pp.81-87
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• 2015

This research suggests a simulator regarding the Manufacturing Process of Electrical Substation System using a simulation method. This study is to propose and apply a new concept of simulation modeling, referred to as integrated Aspect-Oriented Modeling Approach (i-AOMA), in order to efficiently support the design and analysis of a Manufacturing Process of Electrical Substation System. The modeling based on i-AOMA can support easy generation of lots of alternative processes to meet simulation requirements of Manufacturing Process of Electrical Substation System in real case studies.

• 멤브레인
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• 제20권1호
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• pp.29-39
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• 2010

본 연구는 차세대 에너지원으로 주목 받고 있는 직접메탄올연료전지(Direct Methanol Fuel Cell, DMFC)에 대해 mutiscale 기법을 사용하여 DMFC의 MEA부분에 대한 상세 모델링 및 전산모사를 통한 이론적 고찰을 시도하였다. 본 연구에서 이용한 multiscale 모델링 방법은 공정시스템 공학의 kinetic 중심의 모델링 방법과 전산유체역학(Computational Fluid Dynamics, CFD)의 유동중심의 모델링 방법을 유기적으로 결합하여 모사 중간에 필요한 데이터 교환을 함으로써 정확한 모델링 및 전산모사 결과를 얻었다. CFD 모델링으로 유체 이동현상을 3차원으로 해석하였고, 동시에 복잡한 비선형 대수방정식으로 표현되는 반응속도, 전기화학반응을 DAE (Differential & Algebraic Equation) solver로 계산하였다. 모델은 메탄올의 산화반응과 산소의 환원반응을 중심으로 MEA (Membrane Electorde Assembly)부분에서 물리화학적, 전기적 현상 현상을 규명하고, 반응 메커니즘을 구성하였다. MEA 모델은 3차원 공간에서 변위를 가지는 3차원 모델로 구성하였으며, 정상상태 및 등온공정의 조건하에 수립되었다. 이를 통해 channel을 포함한 MEA 부분에서 발생되는 물리적, 화학적, 전기적 현상을 정확히 예측 할 수 있다. 본 연구를 통해 수행된 결과는 DMFC의 실험계획 및 운전조건을 도출함에 있어 매우 유용한 역할을 할 수 있을 것으로 사료되며, 추가적인 연구를 통해 DMFC의 상용화에 크게 이바지 할 수 있을 것으로 사료된다.

• 한국디지털건축인테리어학회논문집
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• 제10권2호
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• pp.49-60
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• 2010

The production process of construction industry is different from thing of the general manufacturing, likewise various participants make temporary teamwork for success of the project through sharing of information. But the each role of participants is individually changed to step in construction process stage and moreover it has complicated, entangled interests. The Construction Management was inducted for the effective management and operation of construction project. The Key of the Construction Management success depends on the cooperative relationship relation to major participants. The domestic construction system is difficult with many trial and errors for the frequent plan change. As the building are more bigger and complicated, Building Information Modeling is demanded design and maintenance. This evaluation was done by the trust on the system as well as Construction Management. And then it applies the BIM it analyzes the example of construcrion project.

• 산업공학
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• 제16권2호
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• pp.258-267
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• 2003

Recently, virtual reality technologies have been rapidly developed and realtime virtual simulation methods have been extensively employed for several application areas such as game, sports, manufacturing, military, and so on. A 3D database in realtime virtual simulation plays a key role because it makes users feel reality in virtual space. In a application view of 3D database, a systematic construction approach is required to reduce its construction time and increase its quality. However, many researches have been mostly focused on realtime graphic issues and its key technologies. In virtual simulation of transportation equipments, this paper proposes a systematic construction process of 3D database consisting of four stages as follows: 1) determine the activity space of a equipment, 2) collect data related to 3D database construction, 3) make a 3-dimensional modeling strategy, and 4) generate and evaluate a 3D model. This paper also introduces a new procedure of 3D environment modeling, which summarizes and expands our modeling experiences, to be used as a modeling guide.

• 한국경영과학회지
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• 제18권3호
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• pp.79-100
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• 1993

This paper proposes an idea of reverse modeling that analyzes LP models and then converts them into an object-oriented model repository. The process of reverse modeling consists of (1) identifying and analyzing source models by meta processor, (2) model decomposition and generalization to scan the models and divide them into model components, and (3) deriving model selection rules from the components by rule generator. Through the process, we can extract reusable model components and build a model base with model selectioon rules. Examples with models created by SML and MODLER modeling languages are given to illustrate the methods. The model base management capabilities provided by reverse modeling can increase the reusabioity of current modeling tools.