• Journal of the Korean Society for Precision Engineering
• /
• v.12 no.5
• /
• pp.136-148
• /
• 1995

In this study, a model integration method is pressented as a new method for development of a parametric simulation model. This method enable us to integrate the special simulation models for each production subsystem into a large simulation model. Not only this large simulation model but also each special simulation model for each production subsytem can be used independently. Using this integration method man can reduce the development time and cost for simulation model development. To show the usefulness of this method, a simulation model for a production system with robots is developed by this model integration method. This simulation model is realized by the integration of two special simulation models, one model for a machining subsystem and the other model for a transport subsystem. The modeled production system consists of the robotic cells for machining and a transport subsystem which enable the material flow among the robotic cells. The flow of workpiece in each robotic cell is not fixed. All machines in a robotic cell are only served by robots.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.31 no.5
• /
• pp.459-465
• /
• 2011

It has been reported that the femoral morphology has a major correlation to femoral neck fractures(FNF). Previous studies to analyze these correlations have relied on mechanical testing and finite element methods. However, these methods have not been widely applied to various femur samples and models. It is because of the availability of the samples from both patients and cadavers, and also of the geometric limitations in changing the shape of the models. In this study we analyzed femoral neck fractures using a parameterized femoral model that could provide flexibility in changing the geometry of the model for the wide applications of FNF analysis. With the parameterization a variety of models could be generated by changing four major dimensions: femoral head diameter(FHD), femoral neck diameter(FND), femoral neck length(FNL), and neck-shaft angle(NSA). We have performed FEA on the models to compute the stress distributions and reaction forces, and compare them with the data previously generated from mechanical testing. The analysis results indicate that the FND is significantly related with the FNF and the FHD is not significantly related with the FNF.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.2
• /
• pp.299-308
• /
• 2008

This paper proposes a new design specification-based band fault modelling technique that can test design specification in a time domain. The band fault model is defined and the conditions of band fault model are gained as normal operation regions are defined. And the conditions of band fault model are used in a 5.25GHz low noise amplifier, then 9 band fault models that can detect hard and parametric faults of active and passive devices are obtained.

• 한국전산유체공학회:학술대회논문집
• /
• 2000.10a
• /
• pp.15-24
• /
• 2000

The transient response of an airfoil to a rapidly deploying spoiler is numerically investigated using the turbulent compressible Navier-Stokes equations in two dimensions. Algebraic Baldwin-Lomax model, Wilcox $\kappa-\omega$ model, and SST $\kappa-\omega$ turbulence model are used to calculate the unsteady separated flow due to the rapid spoiler deployment. The spoiler motion relative to a stationary airfoil is treated by an overset grid hounded by a Dynamic Domain-Dividing Line which has been devised by the authors. The adverse effects of the spoiler influenced by the spoiler location and the hinge gap are expounded. The numerical results are in reasonably good agreement with the existing experimental data.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.12 no.1
• /
• pp.50-57
• /
• 2003

In this paper, an automated design and 3-D modeling system of an axial fan and a boss for cooling towers was developed. API and parametric design Provided by a commercial solid-modeler are engaged to automate modeling process. Design data of the boss are assumed to be given by a user with design experiences while the fan from the fan design program using three-dimensional flow analysis. An algorithm avoiding the interferences between fans and a boss is developed. The design data are registered on the database not only to remove duplicate design but also to transfer the data to ERP system.

• Journal of Institute of Control, Robotics and Systems
• /
• v.8 no.7
• /
• pp.556-562
• /
• 2002

This paper studies the identification of a combustion model, which is used to design a linear controller of a steam generation quantity and harmful exhaust gases of a Refuse Incineration Plant(RIP). Even though the RIP has strong nonlinearities and complexities, it is identified as a MIMO parametric ARX model from experimental input-output data sets. Unknown model parameters are decided from experimental input-output data sets, using system identification algorithm based on Instrumental Variables(IV) method. It is shown that the identified model well approximates the input-output combustion characteristics.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.7
• /
• pp.132-143
• /
• 1999

In this study, an intermediate model is presented as a new method for development of a parametric simulation program. This model enables us to analyze effectively the static and dynamic structure of a real production system. The static structure of the real system can be modelled in an entity-relationship diagram and the dynamic structure of the real system in a Petri net. The intermediate model consists of an entity-relationship diagram and a Petri net. Using this intermediate model man can not only reduce the time and cost for simulation program development, but also increase the modelling reliability of the developed simulation program. To show the usefulness of this intermediate model. the intermediate models for two production subsystems, manufacturing sub-system and transport subsystem, are set up.

• Korean Journal of Computational Design and Engineering
• /
• v.9 no.3
• /
• pp.226-237
• /
• 2004

If the topology changes in the re-generation step of the history-based and feature-based CAD systems, it is difficult to identify an entity in the old model and find the same entity in the new model. This problem is known as 'persistent naming problem'. To exchange parametric CAD models, the persistent naming problem and the naming mapping problem must be solved among different CAD system, which use different naming scheme. For CAD model exchange the persistent naming has its own characteristics compare to that for CAD system development. This paper analyses previous researches and proposes a solution to the persistent naming problem for CAD model exchanges and to the naming mapping problem among different naming schemes.

• Korean Journal of Computational Design and Engineering
• /
• v.6 no.4
• /
• pp.254-262
• /
• 2001

It is not possible to exchange parametric information of CAD (Computer Aided Design) models based on the current version of STEP (Standard leer the Exchange of Product model data). The design intent can be lost during the STEP transfer of CAD models. The ISO Parametrics Group has proposed the SMCH (Solid Model Construction History) schema in June 2000 that includes structures fur exchange of parametric information. This paper proposes the macro parametric approach that is intended to provide capabilities to transfer parametric information. In this approach, CAD models are exchanged in the form of macro files. The macro file contains user commands which are used in the modeling phase. To exchange CAD models using the macro parametric approach, modeling commands of commercial CAD systems are analyzed. Those commands are classified by the grouping method suggested by Bill Anderson. As a neutral file format, a standard modeling commands set has been defined. Mapping relations between the standard modeling commands set and the native modeling commands set of commercial CAD systems are defined.

• Korean Journal of Computational Design and Engineering
• /
• v.14 no.3
• /
• pp.159-167
• /
• 2009

For the robust exchange of parametric CAD model data, it is very important to perform mapping rightly and accurately between different CAD models. However, data model mapping is usually performed on a case-by-case basis. This results in the problem that mapping quality fluctuates very widely depending on the abilities of developers. In order to solve this problem, the concept of symantic distance is adapted and applied to the translation of parametric CAD model data in order to measure the difference between different CAD models quantitatively in a computer-interpretable form and systematize the mapping process.