• The Journal of the Korea Contents Association
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• v.8 no.7
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• pp.66-74
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• 2008

Criticality prediction models to identify most fault-prone modules in the system early in the software development process help in allocation of resources and foster software quality improvement. Many models for identifying fault-prone modules using design complexity metrics have been suggested, but most of them are training models that need training data set. Most organizations cannot use these models because very few organizations have their own training data. This paper builds a prediction model based on a well-known supervised learning model, error backpropagation neural net, using design metrics quantifying SDL system specifications. To solve the problem of other models, this model is trained by generated virtual training data set. Some simulation studies have been performed to investigate feasibility of this model, and the results show that suggested model can be an alternative for the organizations without real training data to predict their software qualities.

• Journal of Advanced Navigation Technology
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• v.15 no.6
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• pp.1047-1052
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• 2011

Various services are created using mobile networks after mobile devices such as smart phones and tablet PCs are propagated rapidly. However, the contents of smart devices are not enough diversity because they depend on games and messaging services primarily. In this paper, we described the study have progressed based on mobile devices and networks using augmented reality technologies about virtual education system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.10a
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• pp.410-413
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• 2018

수년전 세월호 참사로 인해 안전수칙에 대해 경각심을 가지게 된 사회 분위기를 반영하여, 학생들과 일반인을 대상으로 하는 재난 대응 교육 시스템이 매우 시급하게 요구되고 있다. 본 연구에서는 재난 가운데 가장 많이 발생하는 화재 재난에 대해 가상현실을 활용한 4D 재난 대응 훈련시스템을 제안한다. 기업이나 학교 기숙사 등에서는 매년 일정한 패턴(시나리오)의 소방훈련을 받는다. 그러나 이러한 훈련은 한 번에 많은 시간과 공간이 필요하며 년1-2회로서 효율적이지 못하다. 제안하는 시스템은 가상훈련 시스템으로서 실제와 같은 체험이 가능하고 시간과 공간을 절약할 수 있으며 수시로 효율적인 소방훈련을 받을 수 있는 몰입형 4D 가상체험 시뮬레이션이다. 기존의 가상훈련 시스템은 매우 고가의 장비들이 필요하나 제안하는 시스템은 보급의 용이성을 위해, 저가의 HMD(Head Mounted Display)와 트레드밀을 이용하여, 체험할 수 있는 가상현실 4D 몰입형 재난 대응 훈련 콘텐츠이다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.617-622
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• 2018

In industries such as automobiles and semiconductors, a lot of components are produced using PLCs based on an automatic production system. Therefore, an educational platform is needed to provide training in the use of PLCs in the industrial sites. Conventional educational systems, in which PLCs are employed to control sensors and actuators, have been continuously developed. However, these systems present their circuits only in 2D on the screen, which makes it difficult to understand them during the learning process. To overcome these disadvantages, we propose an educational V-Factory system capable of providing PLC training using virtual reality. In addition, thousands of sensors and actuators can be controlled by the V-Factory system through the proposed virtual I/O driver. The motion of the automatic production system can be visualized using virtual reality.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.749-751
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• 2016

Due to the advent of virtual reality, the past communication method using images and video through the expansion into three-dimensional space has been provided more realistic and seamless interaction environment. Unlike reality, virtual reality is under a full human control and due to this benefit can be used as a substitute for reality therefore medicine and healthcare area has attracted attention in the prevention and treatment of dementia utilizing virtual reality. The research provided in this paper is aimed to design a virtual reality-based mild cognitive impairment prevention training system, focusing on the Symptoms of Alzheimer's precursor, mild cognitive impairment.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.2
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• pp.221-230
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• 2023

Purpose : This study was performed to evaluate the effects of virtual reality combined robot assist gait training (VRG) on improvement of balance and respiratory function in chronic stroke patients. Methods : A single-blind, randomized controlled trial (RCT) was conducted with 35 chronic stroke patients. They were randomly allocated 2 groups; VRG group (n=18) and conservative treatment group (CG; n=17). The VRG group received 30 minutes robot assisted gait training combined virtual reality training, robot assisted gait training was conducted in parallel using a virtual reality device (2 sessions of 15 minutes in a 3D-recorded walking environment and 15 minutes in a downtown walking environment). In the conservative treatment group, neurodevelopmental therapy and exercise therapy were performed according to the function of stroke patients. Each group performed 30 minutes a day 3 times a week for 8 weeks. The primary outcome balance and respiratory function were measured by a balance measurement system (BioRescue, Marseille, France), Berg balance scale, functional reach test for balance, Spirometry (Cosmed Micro Quark, Cosmed, Italy) for respiratory function Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV₁), and maximum expiratory volume (PEF) were measured according to the protocol. The measurement were performed before and after the 8 weeks intervention period. Results : Both groups demonstrated significant improvement of outcome in balance and respiratory function during intervention period. VRG revealed significant differences in balance and respiratory function as compared to the CG groups (p<.05). Our results showed that VRG was more effective on balance and respiratory function in patients with chronic stroke. Conclusion : Our findings indicate that VRG can improve balance and respiratory function, highlight the benefits of VRG. This study will be able to be used as an intervention data for recovering balance and respiratory function in chronic stroke patients.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.49-54
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• 2008

In order to do a maintenance task, a maintenance operator should learn the basic skills of the maintenance task such as assembly and disassembly (A/D). However, the key of the learning process is to learn the A/D task intuitively and naturally. Haptic guidance promises to give effectiveness and benefit qualitatively since a person can be trained to do the optimal task based on information that comes from an expert, database, or intelligent algorithms. By applying haptic guidance, a maintenance training process can be made more intuitive and natural in a virtual environment. This paper describes the development of a maintenance training system by using haptic guidance.

• ETRI Journal
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• v.45 no.6
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• pp.1046-1055
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• 2023

We introduce a display for virtual-reality (VR) fire training. Firefighters prefer to wear and operate a real breathing apparatus while experiencing full visual immersion in a VR fire space. Thus, we used a thin head-mounted display (HMD) with a light field and folded optical system, aiming to both minimize the volume for integration in front of the face into a breathing apparatus and maintain adequate visibility, including a wide viewing angle and resolution similar to that of commercial displays. We developed the optical system testing modules and prototypes of the integrated breathing apparatus. Through iterative testing, the thickness of the output optical module in front of the eyes was reduced from 50 mm to 60 mm to less than 20 mm while maintaining a viewing angle of 103°. In addition, the resolution and image quality degradation of the light field in the display was mitigated. Hence, we obtained a display with a structure consistent with the needs of firefighters in the field. In future work, we will conduct user evaluation regarding fire scene reproducibility by combining immersive VR fire training and real firefighting equipment.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.5 s.98
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• pp.112-123
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• 1999

Virtual reality is becoming a powerful tool for various applications such as training, entertainment, surgery, tele-robotics etc. One potential use for virtual reality is to allow several users to interact in a single virtual environment, for example several students sitting in front of different computers connected over a network. In this paper, we present a loosely coupled architecture of haptic display in the multi-user virtual world. The method of controlling haptic devices as well as the way of configuring individual haptic display system are addressed. We will develop an experimental virtual reality system for two remote users and conclude with an experimental work for the task of a multi-player ping-pong and grasping of a common object.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.270-278
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• 2023

We propose a container orchestration system for process workloads that combines the potential of big data and machine learning technologies to integrate enterprise process-centric workloads. This proposed system analyzes big data generated from industrial automation to identify hidden patterns and build a machine learning prediction model. For each machine learning case, training data is loaded into a data store and preprocessed for model training. In the next step, you can use the training data to select and apply an appropriate model. Then evaluate the model using the following test data: This step is called model construction and can be performed in a deployment framework. Additionally, a visual hierarchy is constructed to display prediction results and facilitate big data analysis. In order to implement parallel computing of PCA in the proposed system, several virtual systems were implemented to build the cluster required for the big data cluster. The implementation for evaluation and analysis built the necessary clusters by creating multiple virtual machines in a big data cluster to implement parallel computation of PCA. The proposed system is modeled as layers of individual components that can be connected together. The advantage of a system is that components can be added, replaced, or reused without affecting the rest of the system.