• Journal of Korean Society for Quality Management
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• v.48 no.3
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• pp.433-451
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• 2020

Purpose: The purpose of this study is to investigate how the type of virtual reality content production affects the interaction and immersion that is a virtual reality characteristic, and to provide the platform companies and content producers with the basic information necessary to provide the production and service of content suitable for VR characteristics. Methods: Based on the data collected in the survey, multiple regression analysis and hierarchical regression analysis were used. The measurement tools used in this study were studied through three-dimensional composition, including the characteristics and interaction and immersion of content produced in 2D, 3D and 360°, which are elements of virtual reality characteristics. Results: The results of this study are as follows. Among the types of content production, content produced with 2D and 360 technologies was found to affect immersion, while content produced in 3D affected interaction. Motion sickness has been investigated to affect both immersion and interaction. Conclusion: Service-provided platform enterprises and content-making enterprises should consider content-making and providing services that suit service characteristics and purposes, taking into account the characteristics of interaction and immersion in content-making investment and service delivery.

• Journal of Biomedical Engineering Research
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• v.25 no.2
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• pp.103-109
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• 2004

A virtual arthroscopy is a simulation of optical arthroscopy that reconstructs anatomical structures from tomographic images in joint region such as a knee, a shoulder and a wrist. In this paper, we propose a virtual arthroscopy based on isosurface raycasting, which is a kind of volume rendering methods for generating 3D images within a short time. Our method exploits a spatial data structure called min-max map to produce high-quality images in near real-time. Also we devise a physically-based camera control model using potential field. So a virtual camera can fly through in articular cavity without restriction. Using the high-speed rendering method and realistic camera control model, we developed a virtual arthroscopy system.

• Journal of Fashion Business
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• v.21 no.5
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• pp.30-42
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• 2017

A comprehensive research must be conducted on manufacturing techniques such as patterns and sewing, with the understanding of material properties to satisfy consumers' emotions with a strong fashion trend orientation. Physical and emotional characteristics may change depending on the characteristics of the material, and the overall silhouette and feeling of the garment can change depending on how sewing is conducted.To examine the completeness of a finished garment depending on different kinds of clothing material, this study fabricated an actual garment and a 3D virtual garment as well using 3D CAD IMAGE SYSTEM (CLO 3D, DC Suite, etc.) for a comparative analysis. These two methods have their own advantages and disadvantages. This study selected five of the most representative clothing materials and conducted a comparative analysis on appearance differences between actual clothing and virtual clothing by material. Additionally, the study verified the similarity between actual clothing and virtual clothing by comparing their physical properties by material, and evaluated the objectivity and accuracy of the reproducibility of material properties of virtual clothing.

• The Journal of Korean Physical Therapy
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• v.21 no.2
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• pp.31-38
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• 2009

Purpose: This study was examined the effect of training using a Virtual Reality System on the sitting balance and Activities of Daily Living for patients with a spinal cord injury. Methods: The subjects were divided into an experimental (6 persons) and control group (5 persons). The experimental group trained the 5 programs, three times per week for 6 weeks using the Virtual Reality System and five days for week using conventional physical therapy. The control group trained five days for a week using conventional physical therapy. Results: The difference in the mean Spinal Cord Independence Measurement (SCIM) score in the experimental and control groups was increased to 8.33 and 6.60 (p=0.79), respectively. The difference in the mean functional reaching test in experimental and control group increased to 4.21 and 1.09 (p=0.25), respectively. The difference in the mean sitting time in experimental and control group increased to 41.05 and 10.33 (p=0.66), respectively. There was a difference in the mean of all variances but these differences were not statistically significant. Conclusion: These results suggest that training using the Virtual Reality System increased the SCIM, functional reaching test and sitting time in people with a spinal cord injury.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.11
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• pp.877-882
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• 2016

Disaster robots have accepted tele-operation in order to share the intelligence of human operators and robot systems. Virtual wall is one of the tele-operation technology to support recognition of human operator. If the virtual wall can block the robot from dangers, the operator will feel comfortable and can concentrate on fundamental missions. In this paper, we proposes and compares three methods for virtual wall visualization in tele-operation using 3D reconstruction. First is a virtual wall visualized only with edges. A wall filled with transparent color is the second method. Finally, third method is a texture-mapped virtual wall. In the experiments, we discuss their merits and demerits in view of robot tele-operation.

• Journal of the Korean Society for Library and Information Science
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• v.40 no.4
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• pp.367-383
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• 2006

The purpose of this study is to develop a practical model for enhancing cooperative virtual reference services of public libraries in the nation. The research methods include an examination of model cases from Europe and the V.S. and also an electronic questionnaire survey of 375 public librarians (73% response rate). The study results suggest the need for 'a collaborative virtual reference room' which consists of the collaborative reference database, virtual reference desk, guidance and instruction designed by age groups and/or subjects.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.6
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• pp.671-676
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• 2006

A convolution with HRTF DB and the original sound is generally used to make the method of sound image localization for virtual speaker realization. But it can decline localization by the confusion between up and down or front and back directions due to the non-individual HRTF depending on each listener. In this paper, we study a virtual speaker using a new HRTF, which is grouping the HRTF around the virtual speaker to improve localization between up and down or front and back directions. To effective HRTF grouping, we decide the location and number of HRTF using informal listening test. A performance test result of virtual speaker using the grouped HRTF shows that the proposed method improves the front-back and up-down sound localization characteristics much better than the conventional methods.

• Child Health Nursing Research
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• v.25 no.4
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• pp.496-506
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• 2019

Purpose: The purpose of this study was to examine the effects of a virtual reality simulation and a blended simulation on nursing care for children with asthma through an evaluation of critical thinking, problem-solving processes, and clinical performance in both education groups before and after the educational intervention. Methods: The participants were 48 nursing students. The experimental group (n=22) received a blended simulation, combining a virtual reality simulation and a high-fidelity simulation, while the control group (n=26) received only a virtual reality simulation. Data were collected from February 25 to 28, 2019 and analyzed using SPSS version 25 for Windows. Results: The pretest and posttest results of each group showed statistically significant improvements in critical thinking, problem-solving processes, and clinical performance. In a comparison of the results of the two education groups, the only statistically significant difference was found for critical thinking. Conclusion: Simulation-based education in child nursing has continued to involve high-fidelity simulations that are currently run in many programs. However, incorporating a new type of blended simulation, combining a virtual reality simulation and a high-fidelity simulation, into the nursing curriculum may contribute to the further development of nursing education.

• Journal of The Korean Society of Integrative Medicine
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• v.7 no.2
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• pp.69-76
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• 2019

Purpose : This study examined the effects of a virtual reality rehabilitation program on stroke patients' upper extremity functions and activities of daily living (ADL). Methods : The subjects were equally and randomly divided into an experimental group (n=16) to whom a virtual reality rehabilitation program was applied and a control group (n=16) who received traditional occupational therapy. The intervention was applied five times per week, 30 minutes per each time, for six weeks. Jebsen-Taylor hand function test was conducted and the subjects' Manual Function Test was measured to examine their upper extremity functions before and after the treatment intervention, and a Korean version of modified Barthel index was calculated to look at their activities of daily living. Results : After the intervention, the upper extremity functions and activities of daily living of the participants in both groups significantly improved (p<.05). However, the improvements in these parameters among the participants in the virtual reality rehabilitation program were significantly greater than those in the control group (p>.05). Conclusion : The virtual reality rehabilitation program is a stable and reliable intervention method for enhancing the upper limb functions and activities of daily living of stroke patients.

• International Journal of Computer Science & Network Security
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• v.22 no.11
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• pp.241-247
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• 2022

Ad hoc network is self-organized network powered by battery. The reliability of virtual user identification and channel security are reduced when SNR is low due to limited user energy. In order to solve this problem, a joint virtual user identification and channel security en/decoding method is proposed in this paper. Transmitter-receiver-based virtual user identification code is generated by executing XOR operation between orthogonal address code of transmitter and pseudo random address code of receiver and encrypted by channel security code to acquire orthogonal random security sequence so as to improve channel security. In order to spread spectrum as well as improve transmission efficiency, data packet is divided into 6-bit symbols, each symbol is mapped with an orthogonal random security sequence. Subspace-based method is adopted by receiver to process received signal firstly, and then a judgment model is established to identify virtual users according to the previous processing results. Simulation results indicate that the proposed method obtains 1.6dB E_b/N₀ gains compared with reference methods when miss alarm rate reaches 10^-3.