• Journal of Biomedical Engineering Research
• /
• v.44 no.1
• /
• pp.80-84
• /
• 2023

Electrodes are one of the types of biosensors capable of measuring bio signals, such as electrocardiogram (ECG) and electromyogram (EMG) signals. These electrodes are used in various fields and offer the advantage of being able to measure ECG signals without the need for skin attachment, compared to Ag/AgCl electrodes. The purpose of this study was to evaluate the efficacy of conductive textile electrodes in collecting ECG signals in a bed-like environment. Three adult participants were involved, and a total of 30 minutes of ECG signals were collected for each participant. The collected ECG signals were analyzed to determine the heart rate, normLF and a comparison was made between the conductive textile electrodes and Ag/AgCl electrodes. As a result, the change in heart rate and normLF could be observed, and in particular, the difference between the two electrodes decreased. This study confirmed that conductive textile electrodes can effectively collect ECG signals in a bed-like environment. It is hoped that this research will lead to the development of a system that can detect various sleep-related diseases through the use of these electrodes.

• Journal of the Semiconductor & Display Technology
• /
• v.13 no.1
• /
• pp.19-25
• /
• 2014

This study demonstrates transparent electrodes with characteristics desirable for touch screen panels using carbon nanotubes (CNTs). This has been accomplished by depositing CNTs on glass substrates via spray coating and then depositing thin conductive polymer films on the CNTs via spin coating. For all of the samples, such as CNTs, conductive polymers, and polymer-coated CNTs, the surface morphologies, sheet resistances, visible transmittances, chromatic properties are characterized as functions of their preparation conditions, such as the spray times for CNTs and the spin speeds for conductive polymers. The experimental results confirm that only the polymer-coated CNTs can satisfy all of the requirements that are required for electrodes of touch screen panels, such as the sheet resistance lower than $100{\Omega}/sq$, the visible transmittance higher than 80 %, and the yellowness smaller than 1.

• Journal of Fashion Business
• /
• v.22 no.4
• /
• pp.118-129
• /
• 2018

The purpose of this study is to develop ECG electrode materials for the heart rate monitoring smart band, a smart device used for ECG and heart rate measurement. The purpose of the evaluation is to assess properties and conductivity of electrodes of the existing heart rate monitoring smart band, and to determine suitability through a representative conductive sample. Because level of thickness does not differ significantly from value of conductive specimen from thickness of the smart band, it can be used as a conductive electrode. Surface conductivity of conductive samples and smart bands, is expected to be available as electrodes except for conductive film. Also, since the knit have conductivity only in the metal processing layer, it is necessary to use electrodes on the part of the metal processing layer that is conductive when applying the knit. Tensile strength and electrical conductivity of the tensile were generally revealed to have a tendency. Thickness of the specimen that can be used as an electrode for the smart band is suitable for all samples, electrical resistance, conductive woven, conductive knit, and conductive cord. In the case of conductive cord, however, the electrode attached to the human body will not conform to the flat shape of the electrode attached to the human body. Therefore, the conductive woven and the conductive knit will be available as an electrode.

• Journal of Electrochemical Science and Technology
• /
• v.9 no.4
• /
• pp.330-338
• /
• 2018

The adhesion strength as well as the electrochemical properties of $LiNi_{0.4}Mn_{0.4}Co_{0.2}O_2$ electrodes containing various conductive carbons (CC) such as fiber-like carbon, vapor-grown carbon fiber, carbon nanotubes, particle-like carbon, Super P, and Ketjen black is compared. The morphological properties is investigated using scanning electron microscope to reveal the interaction between the different CC and the active material. The surface and interfacial cutting analysis system is also used to measure the adhesion strength between the aluminum current collector and the composite film, and the adhesion strength between the active material and the CC of the electrodes. The results obtained from the measured adhesion strength points to the fact that the structure and the particle size of CC additives have tremendous influence on the binding property of the composite electrodes, and this in turn affects the electrochemical property of the configured electrodes.

• The Journal of Korea Robotics Society
• /
• v.13 no.4
• /
• pp.265-271
• /
• 2018

The recent prosthetic technologies pursue to control multi-DOFs (degrees-of-freedom) hand and wrist. However, challenges such as high cost, wear-ability, and motion intent recognition for feedback control still remain for the use in daily living activities. The paper proposes a multi-channel knit band sensor to worn easily for surface EMG-based prosthetic control. The knitted electrodes were fabricated with conductive yarn, and the band except the electrodes are knitted using non-conductive yarn which has moisture wicking property. Two types of the knit bands are fabricated such as sixteen-electrodes for eight-channels and thirty-two electrodes for sixteen-channels. In order to substantiate the performance of the biopotential signal acquisition, several experiments are conducted. Signal to noise ratio (SNR) value of the knit band sensor was 18.48 dB. According to various forearm motions including hand and wrist, sixteen-channels EMG signals could be clearly distinguishable. In addition, the pattern recognition performance to control myoelectric prosthesis was verified in that overall classification accuracy of the RMS (root mean squares) filtered EMG signals (97.84%) was higher than that of the raw EMG signals (87.06%).

• Korean Journal of Materials Research
• /
• v.26 no.12
• /
• pp.696-703
• /
• 2016

In this study, we intensively investigated the effect of conductive additive amount on electrochemical performance of organic supercapacitors. For this purpose, we assembled coin-type organic supercapacitor cells with a variation of conductive additive(carbon black) amount; carbon aerogel and polyvinylidene fluoride were employed as active material and binder, respectively. Carbon aerogel, which is a highly mesoporous and ultralight material, was prepared via pyrolysis of resorcinol-formaldehyde gels synthesized from polycondensation of two starting materials using sodium carbonate as the base catalyst. Successful formation of carbon aerogel was well confirmed by Fourier-transform infrared spectroscopy and $N_2$ adsorption-desorption analysis. Electrochemical performances of the assembled organic supercapacitor cells were evaluated by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy measurements. Amount of conductive additive was found to strongly affect the charge transfer resistance of the supercapacitor electrodes, leading to a different optimal amount of conductive additive in organic supercapacitor electrodes depending on the applied charge-discharge rate. A high-rate charge-discharge process required a relatively high amount of conductive additive. Through this work, we came to conclude that determining the optimal amount of conductive additive in developing an efficient organic supercapacitor should include a significant consideration of supercapacitor end use, especially the rate employed for the charge-discharge process.

• 한국신재생에너지학회:학술대회논문집
• /
• 2010.06a
• /
• pp.133.1-133.1
• /
• 2010

In this work, carbon black(CBs)-embed multi-walled carbon nanotubes (MWNTs) as conductive fillers for activated carbon(ACs)-based electrodes for supercapacitor were prepared by chemical reduction of oxidized MWNTs and CBs. The effect of CBs-MWNT composites on electrochemical performances of ACs-based electrodes were investigated as a function of CB-MWNT ratio. It was found that CBs-MWNTs composites were formed by the reduction reaction of the functional groups of oxidized MWNTs and CBs. It was resulted in the conjugation of CBs onto the MWNT having high surface area and aspect ratio, leading to the enhanced electrical properties of MWNTs. The electrochemical performances, such as current density, charge-discharge, and specific capacitance of the ACs/CBs-MWNT electrodes were higher than that of ACs/MWNTs and conventional ACs/CB electrodes, which was attributed to the synergistic effect of CBs-MWNTs as a conductive filler.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.32 no.3
• /
• pp.179-186
• /
• 2019

This work investigated the effects of different conductive agents on the electrochemical properties of anodes. SiOx possesses high theoretical capacity and shows excellent cycle performance; however, the low initial coulombic efficiency and poor electrical conductivity limit its applications in real batteries. In this study, electrodes were fabricated using two different conductive agents, and the resulting physical and electrochemical properties were analyzed. SEM observations confirmed the formation of a CNT conductive network throughout the electrodes, while the electrical conductivity contributed to the electrode was confirmed by impedance measurements. Thus, the electrode fabricated with the CNT conductive agent showed greater capacity and superior cycle performance than did the electrode fabricated using the DB conductive agent.

• Transactions of the Korean hydrogen and new energy society
• /
• v.27 no.3
• /
• pp.276-282
• /
• 2016

The effects of conductive additives in a $La_{0.8}Sr_{0.2}MnO_3$ perovskite bifunctional electrode for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) were investigated in an alkaline solution. Highly porous carbon black (CB) and Ni powder were added to the bifunctional electrodes as conductive additives. The surface morphologies of electrodes containing CB and Ni were observed by scanning electron microscopy (SEM). The current densities for both ORR and OER were changed by the addition of CB. The conductive additive changed physical properties of bifunctional electrodes such as the sheet conductance, gas permeability and contact angle. It was observed that the air permeability of electrode was most effective to enhance the currents for ORR and OER.

• Proceedings of the IEEK Conference
• /
• 2005.11a
• /
• pp.521-524
• /
• 2005

In order to measure ECG in daily life, a new ECG measurement method on bed was developed. The provided method does not require any direct conductive contact between the instrument and bare skin, so that it does not cause the uncomfortable feel of touch and the possible skin trouble which are typical shortcomings of the conventional conductive contact ECG measurement. The provided method utilized an array of high-input-impedance active electrodes fixed on the mattress and an indirect-skin-contact ground made of a large conductive textile sheet and laid on lower area of the mattress. A thin cotton bedcover covered the mattress, the electrodes, and the conductive textile and subjects lay on the mattress over the bedcover. ECG was obtained successfully. However its signal quality is lower and the motion artifact is larger than direct-contact measurement. Careful measurement setup was needed to reduce the motion artifact originated from variation in static electricity. From the ECG obtained by the provided method, R-peak could be discriminated easily and the information about the position and the posture of the subject could be obtained.