• Journal of the Korean Society of Clothing and Textiles
• /
• v.39 no.3
• /
• pp.457-467
• /
• 2015

The demand for coverall-type protective clothing are increasing in many industrial fields; however, it is impossible to evaluate the wearers' apparel fit because there is no commercialized pattern in the market. This study produces a manual for the process of acquiring patterns by separating PPE products into pieces to provide information on acquiring patterns. The analysis was on coverall-type non woven protective clothing in the domestic market, and 4 panels examined the validity, reliability, and efficiency of various possible methods on each step of process. Five steps were conducted to acquire patterns removing wrinkles, marking seams lines, separating seams, and pattern completing. The process of converting these into pattern files was designed through three procedures of digitizing, editing, and exporting and detailed stages. Fitting tests were undertaken, real patterns by actual modeling and pattern files by virtual modeling; all showed similar forms with outfits wearing ready-made protective coveralls. This study sought the most efficient and objective method of virtual modeling and proposed it as a manual. It is expected for the pattern reverse-designing manual through products analysis presented in this study that would be a helpful addition of information to the pattern tracing of pattern-less clothing products.

• Korean Journal of Computational Design and Engineering
• /
• v.13 no.5
• /
• pp.334-341
• /
• 2008

Computer-aided engineering (CAE) analysis is considered essential for product development because it decreases the simulation time, reduces the prototyping costs, and enhances the reusability of product parts. The reuse of quality-assured CAE data has been continually increasing due to the extension of product lifecycle management; PLM, which is widely used, shortens the product development cycle and improves the product quality. However, less attention has been paid to systematic research on the interoperability of CAE data because of the diversity of CAE data and because the structure of CAE data is more complex than that of CAD data. In this paper, we suggest a CAE data exchange method for the effective sharing of geometric and analysis data. The method relies on heterogeneous CAE systems, a virtual reality system, and our developed CAE middleware for CAE data exchange. We also designed a generic CAE kernel, which is a critical part of the CAE middleware. The kernel offers a way of storing analysis data from various CAE systems, and, with the aid of a script command, enabling the data to be translated for a different system. The reuse of CAE data is enhanced by the fact that the CAE middle-ware can be linked with a virtual reality system or a product data management system.

• Journal of the Korean Society of Costume
• /
• v.59 no.8
• /
• pp.26-36
• /
• 2009

The aim of this study is to be the fundamental study for virtual clothing system of the future through a comparative analysis of the difference between a virtual frill skirt and a real frill skirt using a 3-dimensional Apparel cad system. Satin was selected as a comparative fabric of the real skirt and virtual skirt. And compared skirts are frilled 1.5widths, 2widths, and 2.5widths. In case of 1.5widths frilled, the real skirts and virtual skirts showed no significant difference except in shirring frill expression. However, in case of 2widths frilled, and 2.5widths frilled skirts, significant differences in the extent of frill flattening, the sectional diagram of the bottom hem, and the skirt shape. The virtual skirt showed that as its multiple proportion of frill increased, the sidelines of the skirt drooped and excessively extended, and collision detection that the belt was twisted and torn apart arose. Furthermore, not only the frill but also the shape of the skirt was transformed, and the bottom hems were widened back and forth, and the sectional diagram of the bottom hems were transformed into rounded shapes.

• Proceedings of the Korea Society for Simulation Conference
• /
• 1998.10a
• /
• pp.204-208
• /
• 1998

The fundamental issues to evaluate machine tool's performance through simulation pertain to the physical models of the machine tool itself and of process while the practical problems are related to the development of the modular software structure. It allows the composition of arbitrary machine/process models along with the development of programs to evaluate each state of machining process. Surface roughness is one of the fundamental factors to evaluate machining process and performance of machine tool, but it is not easy to evaluate surface roughness due to its tribological complexity. This paper presents an algorithm to calculate surface roughness considering cutting geometry, cutting parameters, and contact dynamics of cutting between tool and workpiece as well as tool wear in turning process. The designed virtual machining system can be used to evaluate the surface integrity of a turned surface during the design and process planning phase for the design for manufacturability analysis of the concurrent engineering.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.8 no.4
• /
• pp.158-168
• /
• 2000

Vehicle driving simulators can provide engineers with benefits on the development and modification of vehicle models. One of the most important factors to realistic simulations is the fidelity given by a motion system and a real-time visual image generation system. Virtual reality technology has been widely used to achieve high fidelity. In this paper the virtual environment including a visual system like a head-mounted display is developed for a vehicle driving simulator system by employing the virtual reality technique. virtual vehicle and environment models are constructed using the object-oriented analysis and design approach. Accordint to the object model a three dimensional graphic model is developed with CAD tools such as Rhino and Pro/E. For the real-time image generation the optimized IRIS Performer 3D graphics library is embedded with the multi-thread methodology. Compared with the single loop apprach the proposed methodology yields an acceptable image generation speed 20 frames/sec for the simulator.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.10 no.1
• /
• pp.195-202
• /
• 2002

By using modeling and simulation. today's design engineers are simultaneously reducing time to market and decreasing the cost of development, while increasing the quality and reliability of their products. A driving simulator is the best example of this method and allows virtual designs of control systems, electronic systems, mechanical systems and hydraulic system of a vehicle to be evaluated before costly prototyping. The objective of this Paper is to develop the virtual Proving: ground using a driving simulator and to show its capabilities of an automotive system development tool. For this purpose, including a real-time vehicle dynamics analysis system, the PC-based driving simulator and the virtual proving ground are developed by using VR(Virtual Reality) techniques. Also ABS HIL(Hardware-In-the-Loop ) simulation is performed successfully.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.7
• /
• pp.80-89
• /
• 2000

Driving simulators provide engineers with a power tool in the development and modification stages of vehicle models. One of the most important factors to realistic simulations is the fidelity obtained by a motion bed and a real-time visual image generation algorithm. Virtual reality technology has been widely used to enhance the fidelity of vehicle simulators. This paper develops the virtual environment for such visual system as head-mounted display for a vehicle driving simulator. Virtual vehicle and environment models are constructed using the object-oriented analysis and design approach. Based on the object model, a three-dimensional graphic model is completed with CAD tools such as Rhino and Pro/ENGINEER. For real-time image generation, the optimized IRIS Performer 3D graphics library is embedded with the multi-thread methodology. The developed software for a virtual driving simulator offers an effective interface to virtual reality devices.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
• /
• 2002.05a
• /
• pp.34-38
• /
• 2002

A virtual human which can evaluate Kansei such as comfort, pain, etc. when the virtual human uses some product is developed. In this paper, method of the evaluation of Kansei by the virtual human is presented. The body of our virtual human is modeled as an uniform non-linear elastic one with a skeleton. The deformation of the body on the contact with some product is simulated using a FEM analysis, and by using of the simulated results (load distribution, strain, etc.) on the contact surface the Kansei is predicted. As examples of the application, comfort of buttocks on seating and pain of arm on hanging of bag are shown. This virtual human can apply for the design of virtual products and also the simulation of medical care.

• IE interfaces
• /
• v.14 no.2
• /
• pp.120-126
• /
• 2001

Virtual manufacturing is a technology facilitating effective development and agile manufacturing of products via sophisticated computer models representing physical and logical schema and behavior of real manufacturing systems including manufacturing resources, environments, and products. Based on these models, virtual manufacturing supports decision making and error checking in the entire manufacturing processes from design to mass production. At first, we analyzed manufacturing preparation activities of the four major production shops such as press, body assembly, painting and final assembly, of a Korean automotive company. We then developed the workflow models out of the analysis by the IDEF methodology, and generated a strategic plan for the systematic application of the virtual manufacturing technologies. We identified many manufacturing preparation activities that can be improved by the application of virtual manufacturing technologies. Finally, we estimated the effect of improvement including time savings in car development processes and corresponding cost savings.

• Journal of the Korean Academy of Esthetic Dentistry
• /
• v.30 no.2
• /
• pp.71-90
• /
• 2021

The virtual patient dataset is a collection of diagnostic data from various sources acquired from a single patient into a coordinate system of three-dimensional visualization. Virtual patient dataset makes it possible to establish a treatment plan, simulate various treatment procedures, and create a treatment planning delivery device. Clinicians can design and simulate a patient's smile on the virtual patient dataset and select the optimal result from the diagnostic process. The selected treatment plan can be delivered identically to the patient using manufacturing techniques such as 3D printing, milling, and injection molding. The delivery of this treatment plan can be linked to the final prosthesis through mockup confirmation through provisional restoration fabrication and delivery in the patient's mouth. In this way, if the diagnostic data superimposition and processing accuracy during the manufacturing process are guaranteed, 3D digital smile design simulated in 3D visualization can be accurately delivered to the real patient. As a clinical application method of the virtual patient dataset, we suggest a decision-making method that can exclude occlusal adjustment treatment from the treatment plan through the digital occlusal pressure analysis. A comparative analysis of whole-body scans before and after temporomandibular joint treatment was suggested for adolescent idiopathic scoliosis patients with temporomandibular joint disease. Occlusal plane and smile aesthetic analysis based on the virtual patient dataset was presented when treating patients with complete dentures.