• Journal of the Korean Academy of Clinical Electrophysiology
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• v.7 no.1
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• pp.23-27
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• 2009

Purpose : The purpose of this study was to examine the effects of different medium frequency currents on afferent fibers. Methods : Thirty healthy volunteers who had no known history of neurological disorders were equally assigned to one of three groups; 2500Hz, 4000Hz, and control and each group was applied to the left wrist in palmer cutaneous branch of radial nerve by different medium frequency currents for 15 min. We measured the changes of thresholds for tactile, two-point discrimination, and thresholds for pain. Results : The results showed that the medium frequency currents stimulation increased thresholds for tactile, two-point discrimination, and thresholds for pain. However, there is no statistically significant difference between group 2500Hz and group 4000Hz. Conclusion : This may explain thresholds for tactile, two-point discrimination, and thresholds for pain plain medium frequency currents stimulation inhibits the excitability of afferent fibers, but the effect of the frequency difference within medium frequency currents is not demonstrated.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.10
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• pp.845-850
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• 2015

This study was designed to investigate the feasibility of utilizing an adaptation for selective elicitation of tactile sensations by means of transcutaneous electrical stimulation. We conducted the first experiment to investigate how the stimulation frequency affected the adaptation. Twenty healthy subjects participated in the second experiment to confirm our proposal that the perception intensity of the low-frequency vibration can be enhanced after a high-frequency adaptation, and vice versa. It was found that (1) a low-frequency stimulation did not adapt the nerve afferents responsible for the high-frequency vibration, (2) a high-frequency stimulation affected the nerve afferents responsible for the low-frequency vibration, but adapted to the pressure sensation more intensely, and (3) more than 62% of the subjects reported a more clear selective sensation after the adaptation had lessened or depressed the unwanted sensation. The observations showed that adaptation of the nerve afferent could be utilized for selective elicitation of tactile sensations.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.1-6
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• 2008

This paper proposes a game controller that provides user motion input and tactile feedback display, in addition to the traditional button-type input. The device utilizes both an accelerometer and an infrared camera in order to estimate 3D position and to recognize user motion. The information from the accelerometer and the camera are integrated for better performance. Various tactile sensations are presented using a voice-coil type vibrator. We apply the proposed controller to a motion-based game and validate its usability.

• Textile Coloration and Finishing
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• v.20 no.6
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• pp.69-74
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• 2008

In this paper, a comfort evaluation system based on a product-focused process design (PFPD) has been proposed for high comforts interior seat covers. Correlations between comforts properties and physical/thermal properties of interior seat covers were examined by combining traditional regression analysis and data mining techniques. A skin sensorial comfort of leather samples was evaluated by only human tactile sensation. The adjectives of leather car seat covers are 'Soft', 'Sticky' and 'Elastic'. Thermo-physiological comfort properties of leather samples were evaluated by only human tactile sensation. The adjectives of leather car seat covers are 'Coolness to the touch' and 'Thermal and humid'. Skin sensorial comforts of cloth samples were evaluated by only human tactile sensation. The adjectives of cloth car seat covers are 'Soft', 'Smooth', 'Voluminous' and 'Elastic'. Thermo-physiological comforts of cloth samples were evaluated by only human tactile sensation. The adjectives of cloth car seat covers are 'Coolness to the touch' and 'Thermal and humid'.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.8
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• pp.743-748
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• 2015

This paper reports the enhanced fabrication and characterization of a $3{\times}3$ array tactile actuator composed of cellulose acetate. The array tactile actuator, with dimensions of $15{\times}15{\times}1mm^3$, consists of 9 pillar-supported cells made from a cellulose-acetate molding. The fabrication process and performance test along with the results for the suggested actuator are explained. To improve the cell-array fabrication, a laser cut was adopted after the molding process. The displacement of the unit cell increased the input voltage and frequency. Various top masses are added onto the actuator to mimic the touch force, and the acceleration of the actuator is measured under actuation. When 2 kV is applied to the actuator, the maximum acceleration is 0.64 g, which is above the vibrotactile threshold. The actuation mechanism is associated with the electrostatic force between the top and bottom electrodes.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.145-150
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• 2005

This paper presents an Electrotactile Display System (ETCS). One of the most important human sensory systems for human computer interaction is the sense of touch, which can be displayed to human through tactile output devices. To realize the sense of touch, electrotactile display produces controlled, localized touch sensation on the skin by passing small electric current. In electrotactile stimulation, the mechanoreceptors in the skin may be stimulated individually in order to display the sense of vibration, touch, itch, tingle, pressure etc. on the finger, palm, arm or any suitable location of the body by using appropriate electrodes and waveforms. We developed an ETCS and investigated effectiveness of the proposed system in terms of the perception of roughness of a surface by stimulating the palmar side of hand with different waveforms and the perception of direction and location information through forearm. Positive and negative pulse trains were tested with different current intensities and electrode switching times on the forearm or finger of the user with an electrode-embedded armband in order to investigate how subjects recognize displayed patterns and directions of stimulation.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.7
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• pp.881-887
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• 2016

In this study, the vibration-based tactile actuator for smart wear applications is presented by using piezoelectric ceramic transducers. The compact wireless actuation system is constructed with a high voltage piezoelectric amplifier, a microcontroller, wireless communication module, and rechargeable lithium-polymer battery. For the wireless communication between a hardware and an operator, the bluetooth-based wireless communication system is prepared and the user interface is provided via smart phone applications. From a series of experimental user studies, it is demonstrated that the proposed vibro-tactile actuator based on piezoelectric ceramic transducers can be effectively applied to smart wear applications.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.4
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• pp.65-70
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• 2020

While the demand for robots in the manufacturing industry has dramatically increased, the industrial robots' functionality is mainly determined by the effector attached to the end of their arms. They need a flexible gripping system that can act as a human hand and easily grasp a variety of objects, which requires resilient sensors. This study clarifies the electrical output characteristics of elastic tactile sensors according to contact terminals because the output characteristics of the tactile sensors vary greatly, depending on the contact material and the method of contact with the conductive wire. Our research considers the Three Roll Mill and Paste Mixer as the dispersion medium, and a nickel- and gold-plated brass electrode as the contact terminal.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.4
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• pp.23-29
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• 2012

Injured peoples usually care their body at medical institutions. But if they need some more rehabilitation to the affected area thus exist. These medical institutions according to the scale there are significant differences in rehabilitation programs, most of the small-scale rehabilitation program for medical doctors and patients to be progression of the conversation is an issue. In this paper, in a small medical facility rehabilitation to assist in the accuracy and reliability, physical contact and force sensors that can measure a combination of substitution and the tactile sensor and tactile sensor alternative with a similar function is proposed. Perceptron neural networks by applying the contact evaluation according to the algorithm to determine the pattern is applied.

• Fashion & Textile Research Journal
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• v.18 no.6
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• pp.878-888
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• 2016

In this study, wool/nylon(50/50%) blend yarn and its fabrics for tra-biz(complex word of travel+business) garment were prepared, and its wear comfort characteristics were investigated through thermal manikin and human-body wearing experiment. In addition, tactile wearing performance from fabric mechanical properties and the dimensional stability and the pilling of the fabric specimen during wearing and dry-cleaning were measured and compared with those of wool 100% fabric specimen. Heat keepability of the wool/nylon(50/50%) blend fabric by thermal manikin experiment was superior than that of wool 100% fabric, this result was verified with human-body wearing experiment and its result coincided well with this experimental result. Tactile wearing performance of the wool/nylon(50/50%) fabric from fabric mechanical properties measured by FAST system was better than that of the wool 100% fabric. The dimensional stability of the wool/nylon(50/50%) fabric was more stable than that of the wool 100% fabric. Because relaxation shrinkage was lower and hygral expansion of wool 100% fabric was more high. However, the breathability and pilling property of the wool/nylon(50/50%) fabric were inferior than those of the wool 100% fabric. The possibility of application for tra-biz garment of wool/nylon(50/50%) blend fabric was observed because of good heat keepability, tactile wearing performance and washing fastness.