• International Journal of CAD/CAM
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• v.2 no.1
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• pp.29-37
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• 2002

De-manufacturing is an entire process of collecting, disassembling, reusing, refurbishing, recycling, and/or disposing products that are obsolete or un-repairable. Designing the products for inexpensive and efficient disassembly enhances the ease of de-manufacturing. Virtual disassembly addresses the difficulty and the methods to disassemble a product in design stage rather than really disassemble a product at the end of its life cycle. Based on the virtual disassembly analysis results, design will be improved for better assembling/disassembling. This paper presents a systematic virtual disassembly methodology such as disassembly relation modeling, path/sequence automatic generation and evaluation. This paper also presents a new virtual disassembly interface paradigm via virtual reality technology for disassembly simulation in virtual environment.

• Journal of Multimedia Information System
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• v.6 no.1
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• pp.7-14
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• 2019

This work presents a virtual prototyping design approach for an area-based image stitching hardware. The virtual hardware obtained from virtual prototyping is equivalent to the conceptual algorithm, yet the conceptual blocks are linked to the actual circuit components including the memory, logic gates, and arithmetic units. Through the proposed method, the overall structure, size, and computation speed of the actual hardware can be estimated in the early design stage. As a result, the optimized virtual hardware facilitates the hardware implementation by eliminating trail design and redundant simulation steps to optimize the hardware performance. In order to verify the feasibility of the proposed method, the virtual hardware of an image stitching platform has been realized, where it required 10,522,368 clock cycles to stitch two $1280{\times}1024$ sized images. Furthermore, with a clock frequency of 250MHz, the estimated computation time of the proposed virtual hardware is 0.877sec, which is 10x faster than the software-based image stitch platform using MATLAB.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.25 no.6
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• pp.12-16
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• 2002

Virtual reality (VR) opened the possibility of moving beyond the 2-D world of conventional desktop systems to an immersive, multi-sensory environment generated by computer graphics. Haptic feedback (Haptics) is now starting to get recognition and use in intensive applications for manipulation, while smell and taste feedback are at the stage of early research. This paper reviews some current works on increased haptic feedback augmentation in virtual reality applications.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.851-854
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• 2009

This Research suggest that key features of lighting simulation and intuitive theaterical design method can unify single system. It can produce the virtual scene of stage which is able to predict the number of lighting box and design budget. the final goal of this research is unifying lighting and stage design into on single system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03b
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• pp.95-98
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• 1999

In this study, a method to find the optimal intermediate die geometry for the multi-stage drawing process for the rectangular rod from a round bar is proposed and a program using the proposed method is developed. On the stage of the design of the intermediate die geometry, the virtual die was constructed using the initial billet as a inlet of the drawing die and the final product as a exit of that and the virtual die was divided by the number of pass. Divided die was transformed into the rectangular one which is the intermediate die geometry for the multi-stage rectangular drawing process. In order to verify the application of the proposed method on the real industrial product, the drawing of the rectangular rod from a round which composed two stage has been performed and simulated by the three dimensional rigid plastic finite element method.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.982-985
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• 2000

This paper presents channel estimation of an asynchronous W-CDMA reverse link using the interpolation and moving average algorithm in frequency-selective Rayleigh fading channel. The proposed algorithm is an interpolated decision-directed (IDD) block-wise moving average (BWMA) algorithm. The IDD-BWMA algorithm performs two- stage processes. The first stage performs data decision to make a virtual pilot channel by using linear interpolation channel estimation scheme. Then, the second stage performs the channel estimation of the “block-wise moving average” type by using a virtual pilot channel obtained in the first stage. By using Monte-Carlo computer simulations, we show that the proposed channel estimator is superior to other estimation schemes such as the WMSA(K=1) and DD-RAKE at higher Doppler frequencies, especially.

• The korean journal of orthodontics
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• v.39 no.5
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• pp.289-299
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• 2009

Objective: The purpose of the present study was to evaluate the effectiveness of the use of Head Posture Aligner (HPA) during cone-beam computed tomography (CBCT) scan in generation of frontal cephalograms using 3D CBCT images. Methods: CBCT scans and frontal cephalograms were made in 30 adult individuals. While a couple of CBCT scan was made for one subject, one was made with conventional method, without use of HPA, the other was acquired with the use of HPA. After creation of virtual frontal cephalogram from each 3D CBCT image, it was traced and compared with the tracing of real frontal cephalogram. Results: In the comparison of the measurements, the virtual cephalograms with the use of HPA did not show statistically significant differences with the real cephalograms whereas the virtual cephalograms without the use of HPA presented significant differences with real cephalograms in many measurements. In the correlation analysis with the measurements of the real cephalograms, the virtual cephalograms with the use of HPA showed higher correlations in all measurements than the virtual cephalograms without the use of HPA. Conclusions: Measurements from CBCT-generated cephalograms become similar to those from real cephalograms with the use of HPA during CBCT scan. Thus, the use of HPA is suggested during the CBCT scan in order to construct accurate virtual frontal cephalograms using 3D CBCT images.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.5
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• pp.2346-2361
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• 2017

A major challenge in cloud infrastructure is the efficient allocation of virtual network elements on top of substrate network elements. Path algebra is a mathematical framework which allows the validation and convergence analysis of the mono-constraint or multi-constraint routing problems independently of the network topology or size. The present study proposes a new heuristic approach based on mathematical framework "paths algebra" to map virtual nodes and links to substrate nodes and paths in cloud. In this approach, we define a measure criterion to rank the substrate nodes, and map the virtual nodes to substrate nodes according to their ranks by using a greedy algorithm. In addition, considering multi-constraint routing in virtual link mapping stage, the used paths algebra framework allows a more flexible and extendable embedding. Obtained results of simulations show appropriate improvement in acceptance ratio of virtual networks and cost incurred by the infrastructure networks.

• Korean Journal of Computational Design and Engineering
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• v.14 no.3
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• pp.150-158
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• 2009

In these days, the importance of design becomes increasing and the design aspect that customers decide to purchase products such as television, mobile phone is more important than functional one. And the progress of virtual reality technology enables us to feel the reality from the virtual prototype as the real one. In this paper, we introduce the collaboration design review system consist of MEMPHIS, CORE. We can create a realistic virtual prototype more fastly, conveniently and efficiently using MEMPHIS and carry out the design review through collaboration using CORE. As a result of this study, it would be possible that decision making can be done effectively at early stage of the design process.

• Journal of Korean Society for Quality Management
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• v.49 no.3
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• pp.405-420
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• 2021

Purpose: This study started with the question of how to use Virtual Reality (VR) contents as a part of the non-face-to-face education tool that has recently attracted attention. Methods: In this paper, the use of VR contents as an educational tool is explained as a process of 'new media access dimension'. The question was explored on why Virtual Reality (or Augmented Reality) contents are not used as educational tools in the educational field. Results: As a result, the lack of 'material access' such as devices and infrastructure affects 'motivational access' approach stage, which is the previous stage. Again, it has a negative effect on literacy, which is 'skill access' approach stage. As it was found that it was not circulating to the level of "motive-material-skill-usage", it was discussed that it was taking a different step from the past adoption process of ICT and smart media. Conclusion: Based on this, it is believed that immersive content will contribute to arousing interest that can be applied and spread in the educational field, and it is also thought that it will be possible to derive academic interest in the educational effect according to the characteristics of immersive content such as VR.