• Geomechanics and Engineering
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• v.35 no.4
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• pp.425-436
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• 2023

An effective tool for researching actual problems in geotechnical and mining engineering is to conduct physical modeling tests using similar materials. A reliable geometric scaled model test requires selecting similar materials and conducting tests to determine physical properties such as the mixing ratio of the mixed materials. In this paper, a method is proposed to determine similar materials that can reproduce target properties using a polynomial model based on experimental results on modeling materials using a gypsum-sand mixture (GSM) to simulate rocks. To that end, a database is prepared using the unconfined compressive strength, elastic modulus, and density of 459 GSM samples as output parameters and the weight ratio of the mixing materials as input parameters. Further, a model that can predict the physical properties of the GSM using this database and a polynomial approach is proposed. The performance of the developed method is evaluated by comparing the predicted and observed values; the results demonstrate that the proposed polynomial model can predict the physical properties of the GSM with high accuracy. Sensitivity analysis results indicated that the gypsum-water ratio significantly affects the prediction of the physical properties of the GSM. The proposed polynomial model is used as a powerful tool to simplify the process of determining similar materials for rocks and conduct highly reliable experiments in a physical modeling test.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.22 no.1
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• pp.90-101
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• 1998

This paper presents a scheduling method that uses Petri net modeling and heuristic search to handle the tool setup. In manufacturing systems, a tool is attached to a particular machine to process a particular operation. The activity to attach a tool to a particular machine and detach the tool from the machine requires time. The processing time of operations varies according to the attached tool and the machine used. The method proposed in this paper uses Petri net to model these characteristics and applies a search algorithm to the reachability graph of the Petri net model to generate an optimal or near-optimal schedule. New heuristic functions are developed for efficient search. The experimental results that show the effectiveness of the proposed method are presented.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.9
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• pp.156-164
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• 1996

Tool interference is one of the most critical problems in machining die cavities and punches. When machining concave or convex regions of cavities with large radius tool in rough cutting, the tool easily overcuts or undercuts the portions of the surface, which result in machining inaccuracy. So the generation of interference-free tool path must be required for more efficient rough cutting. In this paper, we present a method for modeling die cavities which consist of simple surface or analytic compoyund surfaces and present an algorithm for checking and removing the tool interference occurred in machining the die cavities. Using these algorithms, we can represent a die cavity, and check the interfer- ence regions, and then remove these interferences. Especially we focus on the side interference in the sides of analytic elements and base surface boundary.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.569-572
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• 2003

In VLM-ST process, the fine detailed shape processing process is needed due to the use of thick sheets for layers. The developed process perform the fine detailed shape processing in VLM-ST parts using non-contact hot tool. To predict the heat-affected zone and temperature distribution of VLM-ST parts in detailed shaping, the heat flux from the tool to the surface was calculated for the finite element analysis by modeling the tool as a heat source of radiation. The dominant process parameters such as the radiated heat input, the tool speed, and the gap between the tool tip and the foam sheet (tool height) were considered in the analysis. The results showed a good agreement with the experiments.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.638-643
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• 1993

The three dimensional finite element models for the basic deflection of linear motion guides and ball screws were developed. Form the comparison of the results calculated by the finite element method with those by the experiment, it was proved that the modeling method might be applied to real machine tool structures. Form the structural analysis of the headstock of the machine tool, it was found that the static stiffness was calculated within 6.5% error

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.311-315
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• 2000

In thls paper, a remote machine monitoring system for a vimal machine is proposed. The monltonng system is one of the core functmns of a vimd machne that provides a modeling and simulation environment for machining processes and management of the machine life cycle. The proposed system contains the modules for investigating tool wear using neural network and web-based real time process monitoring. An example implementation for tool wear and machining status monitoring is illustrated

• Computers and Concrete
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• v.28 no.6
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• pp.605-619
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• 2021

Building Information Modeling (BIM) models are a powerful tool for preserving and using architectural history. Manually creating information models for such a significant number and variety of architectural monuments as Dong drum towers is challenging. The building logic based on "actual measurement construction" was investigated using the metamodel idea, and a metamodel-based automated modeling approach for the wood framework of Dong drum towers was presented utilizing programmable algorithms. Metamodels of fundamental frame kinds were also constructed. Case studies were used to verify the automated modeling's correctness, completeness, and efficiency using metamodel. The results suggest that, compared to manual modeling, automated modeling using metamodel may enhance the model's integrity and correctness by 5-10% while also reducing time efficiency by 10-20%. Metamodel and construction logic offer a novel way to investigate data-driven autonomous information-based modeling.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.376-380
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• 2002

This research presents modeling of a functional surface which is a constructed free-formed surface. The modeling introduced in this paper adopts polynomial regression that is utilizing approximating technique. The measured data are obtained from measuring with Coordinate Measuring Machine. This paper introduces efficient methods of Reverse Engineering using Polynomial Regression.

• Journal of the military operations research society of Korea
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• v.25 no.1
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• pp.37-54
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• 1999

In this paper, we proposed a modeling method of continuous combat simulation by using VENSIM. VENSIM is a CASE tool for developing continuous simulation. It provides a simple and flexible way of building simulation models from causal loop or influence diagram. As a case model, we developed "a prototype model of battle"incorporating infantry, artillery, air defense weapon, aircraft, and guerrilla engagement.ngagement.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.8
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• pp.27-35
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• 2003

Geometric modeling tool and analysis tool of shell surface have been developed in the different environments and purposes. Thus they cannot be naturally fitted to each other for the integrated design and analysis. In the present study, an integrated framework of geometric modeling, analysis， and design optimization is proposed. It is based on the common representation of B-spline surface patch. In the analysis module, a geometrically-exact shell finite element is implemented. In shape optimization module, control points of the surface are selected as design variables. For the computation of shape sensitivities, semi-analytical method is used. Sequential linear programming(SLP) is adopted for the shape optimization of surfaces. The developed integrated framework should serve as a powerful tool for the geometric modeling, analysis, and shape design of surfaces.