• The Journal of Korea Robotics Society
• /
• v.3 no.1
• /
• pp.9-15
• /
• 2008

Unlike robotic systems, humans excel at a variety of tasks by utilizing their intrinsic impedance, force sensation, and tactile contact clues. By examining human strategy in arm impedance control, we may be able to teach robotic manipulators human''s superior motor skills in contact tasks. This paper develops a novel method for estimating and predicting the human joint impedance using the electromyogram(EMG) signals and limb position measurements. The EMG signal is the summation of MUAPs (motor unit action potentials). Determination of the relationship between the EMG signals and joint stiffness is difficult, due to irregularities and uncertainties of the EMG signals. In this research, an artificial neural network(ANN) model was developed to model the relation between the EMG and joint stiffness. The proposed method estimates and predicts the multi joint stiffness without complex calculation and specialized apparatus. The feasibility of the developed model was confirmed by experiments and simulations.

• Electronics and Telecommunications Trends
• /
• v.34 no.2
• /
• pp.10-18
• /
• 2019

Since the introduction of CRT(Cathode Ray Tube) in the 1950s, display technologies have been developed continuously. Flat panel displays such as PDP(Plasma Display Panel) and LCD(Liquid Crystal Display) were commercialized in the late 1990s, and OLED(Organic Light Emitting Diodes) and Micro-LED(Micro-Light Emitting Diodes) are now being developed and are becoming widespread. In the future, we expect to develop ultra-realistic, flexible, embedded sensor displays. Ultra-realistic display can be applied to AR/VR(Augmented Reality/Virtual Reality) devices and spatial light modulators for holography. The sensor-embedded display can be applied to robots; electronic skin; and security devices, including iris recognition sensors, fingerprint recognition sensors, and tactile sensors. AR/VR technology must be developed to meet technical requirements such as viewing angle, resolution, and refresh rate. Holography requires optical modulation technology that can significantly improve resolution, viewing angle, and modulation method to enable wide-view and high-quality hologram stereoscopic images. For electronic skin, stable mass production technology, large-area arrays, and system integration technologies should be developed.

• Fashion & Textile Research Journal
• /
• v.17 no.4
• /
• pp.597-603
• /
• 2015

This study investigates the actual domestic and overseas cyclewear wearing conditions for male high school cyclists. The study results provide factors and degree of dissatisfaction as basic data for cyclewear development. This study was conducted on 35 male high school cyclists (freshman to seniors) by a questionnaire and interview method. Study results were: Male high school cyclists considered functionality as most important when they bought cyclewear and the brand they most often bought was a cheap domestic brand. Dissatisfaction with the crotch, thigh circumference and minimum leg circumference was higher than other parts during wearing. A cyclist is more sensitive to wear because they require more lower body motion than other parts. Cyclewear should be: less transformed even by frequent laundering, made of breathable material and use a sewing technique that minimizes air resistance and increases fit the body. Functional pads ergonomically designed with high tactile materials should be developed to prevent 'saddle sore' and groin soreness region that happens because of a lower body bending posture when cycling. A follow-up study is recommended to further develop excellence in cyclewear functionality and dimension suitability for male high school cyclists through the size system.

• The Research Journal of the Costume Culture
• /
• v.11 no.5
• /
• pp.721-736
• /
• 2003

As for the purposes of the research: First, on the wearers of snowboard wear on the market, I intend to investigate contents related with purchase, price, brand, style, etc., and grasp requirements and complaints. Second, I intend to know the evaluations of users according to itemized questions on the snowboard wear on the market. Third, I like to provide basic materials by investigating itemized requirements for the development of snowboard wear. On the male & female snowboarders on a skiing ground, I carried out a preliminary investigation in December, 2001, and a main investigation from January to February, 2002. The results are as follows: 1. Many of them purchased imported quality goods, and the rate purchase was high between 20～25 year. Loose two-piece suits of different colors were preferred. The most uncomfortable part proved to be a neck part. 2. The degree of general satisfaction with the snowboard wear on the market was 4.60. And in terms of itemized evaluation, dissatisfaction was found in Clothing construction, facility of laundry and handling, price and brand rather than in style, fiber composition and tactile sensation. 3. In the investigation of the requirements in case of snowboard wear development, the most common requirement was the facility of action. I believe this should be met by study on the choice of pertinent margin and the pattern development.

• The Journal of the Korean dental association
• /
• v.58 no.8
• /
• pp.496-504
• /
• 2020

The osseointegrated implants react biomechanically in a different pattern to occlusal force, due to lack of the periodontal ligament unlike the natural teeth. The implants show markedly less movement and limited tactile sensitivity compared with the natural teeth. The implant occlusion concept aims to avoid overloading on the implants and to direct occlusal loads along the longitudinal axis of the implants, in order to compensate for the different biomechanics of the implants. Although many guidelines and theories on implant occlusion have been proposed, few have provided strong supportive evidence. Moreover, the outcome of treatment often quite successful in spite of different concepts of occlusion and there is an increasing tendency to doubt about the strict theoretical implant-specific occlusion concept. The purpose of this article is to review the previous reports about the concept of implant occlusion and discuss clinical occlusal considerations in implant rehabilitations.

• Tribology and Lubricants
• /
• v.32 no.6
• /
• pp.207-211
• /
• 2016

To interpret the perception that originates from tactile sensibility during people touch and recognize the object surfaces, this study focuses on the development of a friction model that can describe the interaction of a stylus pen sliding over the counter surfaces. In addition, the study includes several other experimental factors such as the pressure, temperature, and topology of surface, which can have an effect on the emotional user experience concerning various surfaces; this research aims to suggest a method to quantitatively evaluate the relation between these experimental parameters and emotional user experience. Accordingly, the objective of research comprises the friction characteristic technology for measurement of fine tribological behavior and a standard to quantify the emotional feedback. Existing panels or input devices that provide interaction feedback about user actions simply operate with a single frequency vibration or sound response. On the contrary, this research investigates various interaction characteristics including friction force, frequency, and surface topology synthetically. Using the developed model, which can explain the relation between the friction parameters and emotional user experience, developers can design their product in order to provide the user with expected emotional sensibility. Consequently, it can contribute to reduce the development cost about sensitivity model.

• Science of Emotion and Sensibility
• /
• v.15 no.4
• /
• pp.441-452
• /
• 2012

Recently, various researches have been attempted to effectively display pseudo-aural senses to the hearing-impaired or the deaf, using vibro-tactile stimulus as well as visual sense. Particularly, it is reported that as complementary senses to support the visual sense, tactile senses displayed by either speakers or vibration motors improve the reality sense significantly but do not nearly improve the emotional sense. Thus, in this study, the thermal sense is selected as another complementary sense to support the pseudo-aural sense display and it is investigated whether the thermal sense could generate a pseudo-aural sense or not. For this purpose, a thermal display module which could effectively display the desired thermal sense is implemented. Then, experiments have been conducted to subjects, which provide them with various types of stimuli combined with the aural, the vibrotactile, and the thermal stimuli along with the visual information. It can be confirmed, through statistical analysis on the data collected from experiments, that subjects could feel a pseudo-thermal sense closer to the real thermal sense which the normal subject feel from both the visual and the aural information, particularly either i) with the thermal stimulus along with the visual information or ii) with both the thermal and the vibrotactile stimuli along with the visual information than only with the visual information. Conclusively, it can be confirmed that the thermal stimulus applied to the skin of the subjects could play a role of effectively displaying pseudo-aural sense related to the thermal sense, as an complementary media for the pseudo-aural display.

• Journal of the Ergonomics Society of Korea
• /
• v.36 no.5
• /
• pp.355-372
• /
• 2017

Objective: The aim of this study is to investigate the performance and usability of ten-finger text entry on Tablet PCs. Background: Generally a soft keyboard is used on Tablet PCs. However, the soft keyboard's performance is usually worse than physical keyboard's performance. In this study, we proposed a modified keyboard for tablet PCs to improve the performance of ten-finger text entry and evaluated the performance and subjective ratings of the keyboard. Method: The modified soft keyboard that is suggested in this study was compared with current Google and Samsung soft keyboards on Tablet PCs. Results: The three keyboards were not significantly different in terms of typing speed, error rate, and mental workload and showed bad performance. Also, the subjective ratings were not shown positively. Conclusion: Based on our results, ten-finger text entry using soft keyboards on Tablet PCs seems to be very difficult. However, we need to research the possibility continuously since ten-finger text entry can improve typing speed. Application: Our study can be a starting point of research that explores ten-finger text entry on Tablet PCs. The new soft keyboard design can be one of the soft keyboard alternatives. However, the key factors to improve the performance and usability of the soft keyboard will not be 'key size' or 'convenience to typing special characters or numbers', but other factors (e.g., 'tactile feedback').

• Proceedings of the ESK Conference
• /
• 1995.10a
• /
• pp.3-12
• /
• 1995

In this research, we investigated the effect of three visual feedback conditions (direct viewing, one-monitor viewing, and tow-monitors viewing) on the task performance of human operator in teloperation task. The three different level of task difficulties under each concitions were performed by thirty-six subjects. The result of the experiments was analysed by the task difficulties, and the measurements of performance are the task completion time and the frequency of task errors. In a teleoperator, the participation of a human operator is always required, and the man-machine interface and the operator's abilities is an important issue. Recently, the different types of sensory feedback conditions(force, vision, sound, tactile, etc) for teleoperation is a very active research area in ergonomics. Among them, visual feedback conditon is an important sense that can provide the information of task environment. Therefore, the sufficient understandings and investigation for human ability under various visual feedback conditions is required to establish the efficient man-machine interface of teleoperation. The result showed that the visual feecback conditions and the level of task difficulties have a significant effect on the task performance. For three level of task difficulties, the task completion time was the shortest under the condition of direct viewing. The number of task errors under the conditions of direct viewing and two-monitors viewing were reduced by more than half compare to that of one-monitor viewing.

• The Research Journal of the Costume Culture
• /
• v.18 no.6
• /
• pp.1063-1075
• /
• 2010

Studying awareness, importance, satisfaction, and wearing behavior of functional textiles for active silver generation related with gender and age is expected to contribute to clothing products development to improve and maintain their health and marketing strategy fit for user characteristics. For empirical research, a survey was developed and the aged 50 and above were 332 respondents. The results of the study are as follows. First, silver generation considered all the clothing comfort sensations important when wearing clothes, such as tactile sensation, clothing pressure sensation, thermal/wet sensation, and motion sensation in human physiological aspect. Also, stretchy fabrics were ranked first in awareness, the number of wearing times, and satisfaction of comfort functional fabrics. More than 30% of silver generation have fifteen items out of 36 functional clothes. Second, in analysis of awareness by gender on functional clothing products, women were more aware of health/safety-oriented fabrics than men were. Otherwise, men had more knowledge about the water-related properties of functional fabrics than women have, such as water/moisture absorptive and water-repellent/vapor permeable fabrics. While women have more indoor casual wear, men had more active sportswear. Also, women expressed a strong preference to the stretchy function of fabrics.