• Transactions on Control, Automation and Systems Engineering
• /
• v.4 no.1
• /
• pp.9-16
• /
• 2002

In this paper, we intend to demonstrate a new intuitive force-feedback device for advanced VR applications. Force feed-back for the device is tension based and is characterized by 7 degrees of freedom (DOF); 3 DOF for translation, 3 DOF for rotation, and 1 DOF for grasp). The SPIDAR-G (Space Interface Device for Artificial Reality with Grip) will allow users to interact with virtual objects naturally by manipulating two hemispherical grips located in the center of the device frame. We will show how to connect the strings between each vertex of grip and each extremity of the frame in order to achieve force feedback. In addition, methodologies will be discussed for calculating translation, orientation and grasp using the length of 8 strings connected to the motors and encoders on the frame. The SPIDAR-G exhibits smooth force feedback, minimized inertia, no backlash, scalability and safety. Such features are attributed to strategic string arrangement and control that results in stable haptic rendering. The design and control of the SPIDAR-G will be described in detail and the Space Graphic User Interface system based on the proposed SPIDAR-G system will be demonstrated. Experimental results validate the feasibility of the proposed device and reveal its application to virtual reality.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.43 no.4 s.310
• /
• pp.103-112
• /
• 2006

In this paper, we propose a PC based immersive virtual environment system with expandability and compatibility in contrary to existing immersive virtual environment(IVE) systems which have been implemented by supercomputer or special computing system. The application based on commercial personal compute may have two major advantage: one is variety of resources, the other is user-friendly interface. This system intends to offer easy contact to IVE system, realistic images, and convenience. Also, the system can handle various virtual reality at real-time and make it easier to interface existing complicated haptic device. Geometric techniques are adopted to calculate and visualize the physical phenomenon to speed up the computing time. The proposed implementation method of PC based immersive virtual environment system is implemented to the example in which user move around inside of and interact with virtual office environment wearing data glove, behavior recognition devices, and HMD.

• Journal of the Semiconductor & Display Technology
• /
• v.15 no.2
• /
• pp.66-69
• /
• 2016

Recently, augmented reality and virtual reality in the ICT sector have been highlighted. So also interested in related HMD areas to facilitate contact with the VR content is being attend. This paper proposes a method for implementing to the virtual reality through the mobile HMD device with the real time 360 image. This system is required the real time 360 image streaming server configuration and image processing for augmented reality and virtual reality. The configuration of the streaming server is configured the DB server to store images and the relay server that can relay images to other devices. Augmented image processing module is composed based on markerless tracking, and there are four modules that are recognition, tracking, detecting and learning module. Also, the purpose of this paper is shown the augmented 360 image processing through the Mobile HMD.

• Journal of Digital Contents Society
• /
• v.18 no.3
• /
• pp.429-434
• /
• 2017

VR technology has been repidly developing thanks to development of a huge amount of new contents as well as new devices optimized for the virtual environment. Businesses in the IT sector have already started focusing on virtual reality, which might be considered as the center of industry in the future, and concentrated their efforts on development of VR, hardware and technology. Also, development of various VR device would lead to prosperity of media contents based on VR, Still, cyber sickness remain a serious problem waiting for an appropriate solution. In this paper we discuss causes for cyber sickness, analyze the relationship between cyber sickness and reflex eye movement and propose guidelines for the process of producing contents. In addition, we show experiments analyzing the effect of the proposed measures for alleviating cyber sickness.

• Tribology and Lubricants
• /
• v.40 no.2
• /
• pp.39-46
• /
• 2024

The Morton effect (ME) is an instability phenomenon occurring in rotating machineries supported by fluid film bearings and is induced by the thermal deformation of the overhung mass, which is a part of the rotating shaft. Herein, we describe the ME during the high-speed balancing test of a 20 MW class steam turbine. Additionally, to predict the rotating speed at which the ME occurs, we apply the sensitivity vector theory for the steam turbine. During the operation of the steam turbine, we observe a continuous increase in vibration and hysteresis near the rated speed, which is typical of the ME. Increasing the temperature of the lubricating oil supplied to the bearings from 40 to 60℃ suppresses the occurrence of the ME. The rotordynamic analysis for the steam turbine suggests the existence of a mode in which the overhung mass undergoes significant deformation near the rated speed, and we presume that such a mode will increase the occurrence of the ME. The predicted rotating speed of ME occurrence, obtained through the sensitivity vector method, correlates with the test results. Moreover, increasing the temperature of the supplied lubricating oil mitigates the occurrence of ME by reducing the sensitivity between the temperature deviation vector and unbalance mass vector.

• Journal of Korea Multimedia Society
• /
• v.25 no.3
• /
• pp.546-557
• /
• 2022

Recently, the demand to interpret image data with artificial intelligence in various fields is rapidly increasing. Object recognition and detection techniques using deep learning are mainly used, and video integration analysis to determine unstructured object recognition is a particularly important problem. In the case of natural disasters or social disasters, there is a limit to the object recognition structure alone because it has an unstructured shape. In this paper, we propose intelligent video integration analysis system that can recognize unstructured objects based on video turning point and object detection. We also introduce a method to apply and evaluate object recognition using virtual augmented images from 2D to 3D through GAN.

• KEPCO Journal on Electric Power and Energy
• /
• v.7 no.2
• /
• pp.323-328
• /
• 2021

Diagnostic models are required. Data augmentation is one of the best ways to improve deep learning performance. Traditional augmentation techniques that modify image brightness or spatial information are difficult to achieve great results. To overcome this, a generative adversarial network (GAN) technology that generates virtual data to increase deep learning performance has emerged. GAN can create realistic-looking fake images by competitive learning two networks, a generator that creates fakes and a discriminator that determines whether images are real or fake made by the generator. GAN is being used in computer vision, IT solutions, and medical imaging fields. It is essential to secure additional learning data to advance deep learning-based fault diagnosis solutions in the power industry where facilities are strictly maintained more than other industries. In this paper, we propose a method for generating power facility images using GAN and a strategy for improving performance when only used a small amount of data. Finally, we analyze the performance of the augmented image to see if it could be utilized for the deep learning-based diagnosis system or not.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.20 no.2
• /
• pp.83-87
• /
• 2020

Foreign body (FB) ingestion is commonly seen in the ear nose and throat (ENT) field, with different presentations and sequelae. FBs can arrest in the upper aerodigestive tract or continue further down into either the airway tract to the bronchus or the digestive tract to the intestines. The pathway of an FB depends on the size and shape of the FB and how sharp its edges are. Since the 20th century, the use of disposable stainless-steel needles in the oral cavity has proven to be an effective and safe method for performing various intraoral procedures like dental infiltration or a root canal wash. Complications from their use are rare. Generally, dental needle breakages are caused by patients biting the needle, incorrect injection techniques, or inadequate preventative measures. The sudden movement of a patient during a procedure is one of the most common causes of breakage. Occasionally, needles are swallowed during dental procedures such as a root canal. Here, we report a case of a patient that swallowed a broken needle during a dental procedure. A few days later, the patient presented with neck pain, swelling, and a FB sensation. When the patient presented, she claimed that her symptoms had onset after consuming a meal containing duck meat. Initially, the patient was diagnosed as having ingested a duck bone. However, intraoperatively, the FB was discovered to be an injection needle that had migrated from the throat to the neck.

• Knowledge Management Research
• /
• v.1 no.1
• /
• pp.127-137
• /
• 2000

Effective knowledge sharing and creating requires human networking as well as system. Corporation 'S' organized 'community of practice(CoP),' which is a virtual group based on work process, skill, and interest. The purpose of this study is to suggest effective CoP establishment and implementation methods, based upon 'S' experience. The effective methods this study suggests are : setting up clear CoP objectives by each CoP; dual CoP system with career centered and subject centered; alignment with business strategy; guide by knowledge integrator, and professional competence development as CoP purpose. Key success factors to CoP activities also include effective communication, facilitators' competency, and managers' support.

• Journal of Information Technology Applications and Management
• /
• v.18 no.1
• /
• pp.75-100
• /
• 2011

For decades, thousands of corporation introduced knowledge management systems to respond knowledge-based society. However, it seems that the systems merely focusing on knowledge accumulation and its sharing have been bounded by many restrictions in terms of new knowledge creation based on the life cycle of knowledge management systems. Moreover, recently, a variety of knowledge management activities regarding organization, systems, and process is emphasized as a strategic asset for a corporation to create core knowledge. Therefore, this study adopted the Csikszentmihalyi's flow theory to investigate the factors affecting knowledge creation and the success factors of knowledge management systems in virtual space. Prior studies argued that flow experience should be a prerequisite for creative knowledge creation. In that vein, this research revealed the causal relationships for flow experience between the determinants of clear goal, immediate feedback, congruence of challenge and skill. Additionally, it empirically examined how flow experience affected the exploratory behavior of knowledge creation.