• International conference on construction engineering and project management
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• 2009.05a
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• pp.579-586
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• 2009

4D simulation integrates the 3 dimensional model of a building with the construction schedule, and it leads to the possibility of virtually checking the construction process and the building itself in advance. However, the existing problem of 4D simulation is the difference between the demands of architects, engineers, and construction site workers in 4D simulation. This study suggests the possible way to enhance the availability of 4D simulation, considering more the practical demands from the construction site. In order to conduct this study, we build a 3D BIM model of a business-residential complex and link the model with the pre-defined construction schedule in order to make a 4D simulation. This study concludes with the optimized 4D simulation methodology based on BIM model considering the demands in perspective of the construction site. It would contribute to the harmonic collaboration among architects, engineers, and labors in the construction site when using 4D simulation based on BIM model.

• Journal of Powder Materials
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• v.9 no.4
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• pp.245-250
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• 2002

In this paper we presented numerical method for the simulation of powder injection molding filling process, which is one of the key processes in powder injection molding. Rheological properties of powder binder mixture such as slip phenomena and yield stress were introduced into the numerical analysis model of powder injection molding filling simulation. Numerical model can be classified into two types. One is 2.5D model which can be introduced to a arbitrary thin geometry and the other is full 3D model which can be applied to a general 3D shape. For 2.5D model we showed the validity of our CAE system with several verification examples. Finally we suggested flow analysis model for 3D powder injection molding filling simulation.

• Journal of International Society for Simulation Surgery
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• v.4 no.1
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• pp.9-12
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• 2017

Purpose Surgery for separating craniopagus twins involves many critical issues owing to complex anatomical features. We demonstrate a 3D printed model and virtual reality (VR) technologies that could provide valuable benefits for surgical planning and simulation, which would improve the visualization and perception during craniopagus surgery. Material & Methods We printed a 3D model extracted from CT images of craniopagus patients using segmentation software developed in-house. Then, we imported the 3D model to create the VR environment using 3D simulation software (Unity, Unity Technologies, CA). We utilized the HTC Vive (HTC & Valve Corp) head-mount-display for the VR simulation. Results We obtained the 3D printed model of craniopagus patients and imported the model to a VR environment. Manipulating the model in VR was possible, and the 3D model in the VR environment enhanced the application of user-friendly 3D modeling in surgery for craniopagus twins. Conclusion The use of the 3D printed model and VR has helped understand complicated anatomical structures of craniopagus patients and has made communicating with other medical surgeons in the field much easier. Further, interacting with the 3D model is possible in VR, which enhances the understanding of the craniopagus surgery as well as the success rate of separation surgery while providing useful information on diagnosing and surgery planning.

• Journal of Advanced Navigation Technology
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• v.21 no.3
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• pp.264-271
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• 2017

This paper presents air traffic control simulation model for generating 4D trajectory, and aircraft dynamic model based on 4D trajectory information. With aircraft parameters from BADA and Total Energy Model, the trajectory is defined through modified Bezier curve and the simulation supports two aircraft control methods based on controlled time of arrival (CTA) or airspeed. The simulation results shown that flight time and path were almost identical to the defined trajectory, and derived the differences of each control methods according to wind conditions. Based on the simulation model developed in this study, it is expected to be applied to various air traffic management researches. Future studies will focus on applying optimization techniques in order to minimize the difference between generated trajectories and actual flight routes. This work will increase utilization of developed simulation futhermore.

• Elastomers and Composites
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• v.53 no.4
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• pp.226-233
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• 2018

Elastomers based on the thermoplastics are widely used in rubber industries. Thermoplastic elastomers have the advantages of an easy shaping process and elimination of recycling problems. Thermoplastic polyester elastomer (TPE) is used for making rubber bands in wearable devices and its applications are increasing. In this study, five wrist bands were designed and their mechanical behaviors were examined by computer simulation, using hyper elastic models, Mooney-Rivlin and Ogden models, and a linear elastic model. Simulation results were compared and discussed in terms of band design and material model.

• Korean Journal of Construction Engineering and Management
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• v.5 no.4 s.20
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• pp.107-114
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• 2004

This paper represents the application of the 3D CAD Model data for 4D simulation and quantity estimation. These support the effective and practical use of 4D CAD model. By using and manipulating the 3D CAD model information, scheduling and quantity estimation could be developed more quickly and effectively. So the 3D CAD model information is made use of not only drawing a blueprint but also playing an important part of data integration platform. The scheduling module sets up the schedule generation logic that consists of period, priority of element arrangement, and time lag of floor placement. It sorts the working items as a priority of working process. And the quantity estimation module queries the material quantity of the structural elements according to the scheduling conditions. These two modules are developed using the 3D CAD model information and assist the function of 4D CAD model.

• IE interfaces
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• v.25 no.2
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• pp.216-228
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• 2012

BIM-based 4D simulation makes people easily understand complex construction process using 3D graphics model and helps them review and identify the construction schedule in each phase of the construction process. Moreover, 4D simulation can be used as reference data to determine the validity of the process in the design phase and will be utilized as a measure for checking the construction process. Therefore 4D simulation of construction improves efficiency of project management. However, current commercial applications available for 4D simulation do not provide sufficient functions for connection of 3D models and process information. In this paper, we propose an automated generation method through the definition of the process based on a work method template and developed the template based schedule generation system (TSGS).

• The KIPS Transactions:PartA
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• v.13A no.4 s.101
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• pp.371-380
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• 2006

This paper utilizing model picture of finished clothes in fashion design field various material (textile fabrics) doing Draping directly can invent new design, and do not produce direction sample or poetic theme width and confirm clothes work to simulation. Also, construct database about model and material image and embodied system that can confirm Mapping result by real time. And propose clothes simulation system to dress to 3D human body model of imagination because using several cloth pieces first by process to do so that can do simulation dressing abstracted poetic theme width to 3D model here. Proposed system creates 3D model who put clothes by physical simulation that do fetters to mass-spring model after read 3D human body model file and 2D foundation pattern file. System of this treatise examines collision between triangle that compose human body model for realistic simulation and triangle that compose clothes and achieved reaction processing. Because number of triangle to compose human body is very much, this collision examination and reaction processing need much times. To solve this problem, treatise that see could create realistic picture by method to diminish collision public prosecutor and reaction processing number, and could dress clothes to imagination human body model within water plant taking advantage of Octree space sharing techniques.

• Journal of the Korea Society for Simulation
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• v.4 no.1
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• pp.113-119
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• 1995

In 3D computer graphics, fractal techniques have been applied to terrain models. Even though fractal models have become popular for recreating a wide variety of the shapes found in nature, a specific 3D terrain model such as Uleung Island could not be formulated by statistical fractals easily owing to the random effects. However, by locating the midpoints on the edges and the surface of a specific terrain such as Uleung Island, a similar shape of the terrain model can be simulated. This paper shows the way of simulating 3D Uleung Island terrain model by the statistical fractals wherein the subdivision algorithm is used.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.12 no.6
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• pp.890-898
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• 2001

4H-SiC(silicon carbide) MESFET large signal model was studied using modified Materka-Kacprzak large signal MESFET model. 4H-SiC MESFET device simulation have been conducted by Silvaco\`s 2D device simulator, ATLAS. The result is modeled using modified Materka large signal model. simulation and modeling results are -8 V pinch off voltage, under V$\_$GS/=0 V, V$\_$DS/=25 V conditions, I$\_$DSS/=270 mA/mm, G$\_$m/=52.8 ms/mm were obtained. Through the power simulation 2 GHz, at the bias of V$\_$GS/-4 V md V$\_$DS/=25 V, 10 dB Gain, 34 dBm (1dB compression point)output porter, 7.6 W/mm power density, 37% PAE(power added efficiency) were obtained.7.6 W/mm power density, 37% PAE(power added efficiency) were obtained.d.