• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1026-1034
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• 2002

This paper describes the development of machining simulation program which is able to design cutter profile and 3-dimensional geometry for rotors in screw compressor. Based on the symmetric rotor profiles developed previously, cutters are designed and 3-dimensional geometries of rotors are generated by using simulation program. Symmetric rotors are manufactured by a universal milling machine, and surface geometries of them are measured by a 3-dimension scanner It is shown that simulation program developed is useful to design cutter for rotor manufacturing and to generate the 3-dimensional helicoid geometry of rotor in screw compressor.

• Journal of the Korean Association of Geographic Information Studies
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• v.11 no.2
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• pp.121-131
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• 2008

Two dimensional road design is connoting danger factor because different point between design standard and driver's reaction. Consequently two dimensional road design is difficult to recognize problem that happen beforehand when before construction. Therefore three dimensional road design that can grasp problem after completion is required. In this study, three dimensional road was designed to evaluate road that is designed. Road designed by Inroad that is road design program. DTM is created using digital map and elevation data. Three dimensional road was designed by integrated DTM of road and topography. Road design evaluation was performed in three dimension. Driving simulation and sight distance assessment were carried out to estimate stability of alignment. Shadow simulation was executed on icy road section for bad section of icy road surface. As a result of evaluation, this study could confirm shape of road after completion. And sight distance could be calculated and visually confirmed. Also, icy road sections were extracted through shadow simulation.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.241-248
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• 1998

• Journal of the Korean Ceramic Society
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• v.34 no.9
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• pp.979-985
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• 1997

The three-dimensional particle packing process is simulated using Lahey FORTRAN 90 as a programming language running on a personal computer. Particle clusters constructed with rearrangement which occurs during packing have higher average coordination number and packing density than particle clusters rearranged after packing. Rearranging particles can not completely block other particles from entering pore volume in 3-dimensional packing unlike in 2-dimensional packing. It is found that there is a region of instability where lower packing density results from the destruction of the ordered packing.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.40 no.1
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• pp.32-36
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• 2014

Preoperative surgical simulation in orthognathic surgery has progressed in recent years; the movement of the mandible can be anticipated through three-dimensional (3D) simulation surgery before the actual procedure. In this case report, the mandible was moved to the intended postoperative occlusion through preoperative surgical 3D simulation. Right-side condylar movement change was very slight in the surgical simulation, suggesting the possibility of mandibular surgery that included only left-side ramal osteotomy. This case report describes a patient with a mild asymmetric facial profile in which the mandibular menton had been deviated to the right and the lips canted down to the left. Before surgery, three-dimensional surgical simulation was used to evaluate and confirm a position for the condyle as well as the symmetrical postoperative state of the face. Facial asymmetry was resolved with minimal surgical treatment through unilateral intraoral vertical ramus osteotomy on the left side of the mandible. It would be a valuable complement for the reduction of the surgical treatment if one could decide with good predictability when an isolated intraoral vertical ramus osteotomy can be done without a compensatory osteotomy on the contralateral side.

• Proceedings of the KWS Conference
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• 2003.11a
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• pp.150-152
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• 2003

This simulation was carried out to estimate the process time and to improve the operation efficiency. The subassembly process consists of piece arrangement, tack welding, robot welding, manual welding and the robot welding of them was the focus of the simulation. Robot welding stage was analyzed by UML and IDEFø method, and then it was represented as the three-dimensional model(simulator) based on the analysis. The output of this simulation was the cycle time for one day's work. The cycle time for the different torch and the different piece arrangement was investigated by the 3-dimensional simulation.

• Journal of International Society for Simulation Surgery
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• v.3 no.1
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• pp.36-38
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• 2016

Fibrous dysplasia is a relatively rare disease but the management would be quite challenging. Because this is not a malignant tumor, the preservation of the facial contour and the various functions seems to be important in treatment planning. Until now the facial bone reconstruction with autogenous bone would be the standard. Although the autogenous bone would be the ideal one for facial bone reconstruction, donor site morbidity would be the inevitable problem in many cases. Meanwhile, various types of allogenic and alloplastic materials have been also used. However, facial bone reconstruction with many alloplastic material have produced no less complications including infection, exposure, and delayed wound healing. Because the 3D printing technique evolved so fast that 3D printed titanium implant were possible recently. The aim of this trial is to try to restore the original maxillary anatomy as possible using the 3D printing model, based on the mirrored three dimensional CT images based on the computer simulation. Preoperative computed tomography (CT) data were processed for the patient and a rapid prototyping (RP) model was produced. At the same time, the uninjured side was mirrored and superimposed onto the traumatized side, to create a mirror-image of the RP model. And we molded Titanium mesh to reconstruct three-dimensional maxillary structure during the operation. This prefabricated Titanium-mesh implant was then inserted onto the defected maxilla and fixed. Three dimensional printing technique of titanium material based on the computer simulation turned out to be successful in this patient. Individualized approach for each patient could be an ideal way to restore the facial bone.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.11
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• pp.4718-4725
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• 2011

Intake-air flow and distribution characteristics of the 1600cc gasoline engine intake manifold have been studied using the computer simulation. Simulation has been conducted using both one-dimensional performance simulation and three-dimensional CFD software. Steady state flow simulation result of the intake manifold shows good distribution characteristics that the standard deviation of flow coefficients is below 1.0 percentage for both one- and three-dimensional simulation. Even though one-dimensional simulation result slightly overestimates compared with three-dimensional simulation result, both results show very good agreement in flow coefficient trend. Also, unsteady state simulation result shows consistent distribution characteristics with that of steady state. It is shown that unsteady state distribution characteristics might be able to be predicted through the steady state mass distribution result.

• Journal of the Korea Society of Computer and Information
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• v.13 no.7
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• pp.221-229
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• 2008

The development of computer and multimedia brought out new technology, that is, virtual reality. Computer simulation adaptation among the technologies of the virtual reality is spreaded into air service, motor vehicle, medical science, sports, education, even fashion industry. This study look into 2-dimensional hair-style computer simulation system which is started to common use nowadays and the 3-dimensional system which is under the development. And this study proposed several problems such as heavy 3D system booth and the low price but low qualified camera in order to commercialize the 3D system. This study also suggest several alternative, for instance, the change from object photography method to panoramic photography method, the substitute by middle or high end and high qualified camera.

• The Journal of the Korea Contents Association
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• v.19 no.2
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• pp.469-476
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• 2019

Robotic motion is designed by the rotation and the translation of multiple joint coordinates in a three-dimensional space. Joint coordinates are generally modeled by homogeneous transform matrix. However, the complexity of three dimensional motions prefers the visualization methods based on simulation environments in which models and generated motions work properly. Many simulation environments have the limitations of usability and functional extension from platform dependency and interpretation of predefined commands. This paper proposes the web-based three dimensional simulation environment toward high user accessibility. Also, it covers the small size web server that is linked with Python script. The non linearities of robot control apply to verify the computing efficiency, the process management, and the extendability of user scripts.