Fine Electrodes Research Articles

Simultaneous formation of fine and large-area electrode patterns using screen-offset printing and its application to the patterning on adhesive materials

Additive-type printing techniques such as gravure-offset printing and screen printing are effective for low-cost and ecofriendly electrode pattern formation. Gravure-offset printing is effective for fine pattern formation with widths on the order of 10–20 µm, whereas screen printing is effective for the formation of large-area patterns. However, it is difficult to simultaneously form fine and large-area patterns using these printing techniques. In this study, we demonstrate that fine (minimum width of 15 µm) and medium- as well as large-area patterns can be formed simultaneously using our developed screen-offset printing technique, which is a combination of screen printing on a silicone blanket and transfer printing from the blanket to a substrate. Furthermore, we demonstrate the application of our method to printing on adhesive materials, which allows electrode formation without applying heat to the film substrate.

表面微細電極構造を有するDBDプラズマアクチュエータの誘起噴流特性に関する実験的研究

表面微細電極構造を有するDBDプラズマアクチュエータの誘起噴流特性に関する実験的研究

Electromyography of Swallowing with Fine Wire Intramuscular Electrodes in Healthy Human: Amplitude Difference of Selected Hyoid Muscles

Few studies have examined the intensity of muscle activity during swallowing in healthy humans. We examined selected hyoid muscles using fine wire intramuscular electromyography (EMG) during swallowing of four food consistencies. Thirteen healthy adults were studied using videofluorography and EMG of the anterior belly of digastric (ABD), geniohyoid (GH), sternohyoid (SH), and masseter (MA; surface electrodes) while ingesting thin liquid (three trials) and solid food of three consistencies (banana, tofu, and cookie, three trials each). After rectification, integration, and normalization, peak EMG amplitudes for each muscle in each trial were measured. Hyoid displacements were measured in two dimensions. Data were analyzed using repeated measures ANOVA with Bonferroni correction. GH had the highest adjusted amplitude for both solids and liquid. For MA and ABD, amplitude was highest with triturated cookie. For ABD, amplitude was lowest with liquid. There were no significant food consistency effects for GH or SH. Hyoid displacements were greatest for cookie and the lowest for liquid. EMG amplitude varied with initial food consistency. The high peak EMG amplitude of GH is consistent with its essential role in opening the upper esophageal sphincter. High MA amplitude with hard solid foods is likely due to the higher tongue-palate pressure with triturated solids. The higher ABD amplitude with solid food is associated with greater hyoid displacement. These findings support the existence of a central pattern generator that modifies the level of muscle activity during pharyngeal swallowing in response to input from mechanoreceptors in the oral cavity.

Wrist rigidity assessment during Deep Brain Stimulation surgery.

Parkinson's Disease (PD) patients often need Deep Brain Stimulation (DBS) surgery when they become intolerant to drugs or these lose efficiency. A stimulation electrode is implanted in the basal ganglia to promote the functional control of the deregulated dopaminergic motor pathways. The stimulation target is defined by medical imaging, followed by electrophysiological inspection for fine electrode position trimming and electrical stimulation tuning. Intra-operative stimulation of the target and the evaluation of wrist rigidity allows to choose the stimulation parameters which best alleviate PD symptoms without side effects. Neurologists impose a passive wrist flexion movement and qualitatively describe the perceived decrease in rigidity under different voltages, based on its experience and with subjectivity. We designed a novel, comfortable and wireless wearable motion sensor to classify the wrist rigidity by deriving a robust signal descriptor from angular speed values and a polynomial mathematical model to classify signals using a quantitative continuous scale. The descriptor significantly (p<0.05) distinguished between non-rigid and rigid states, and the classification model labelled correctly 83.9% of the evaluated signals against the blind-agreement of two specialists. Additionally, we developed a methodology to detect cogwheel rigidity from the angular speed signal with high sensitivity (0.93). Our system provides a reliable evaluation of wrist rigidity, improving upon the inherent subjective clinical evaluation while using small, simple and easy to use motion sensor.

Effect of Conductive Filler Shape on Fine Electrode Pattern of Photosensitive Silver Pastes

전도성이 우수한 미세 전극 패턴을 형성하기 위해 은 분말을 함유한 감광성 페이스트를 구현하고 입자의 형태에 따른 전기적 특성을 평가하였다. 노볼락 에폭시 변성 아크릴레이트 올리고머, 아크릴레이트 단량체, 광개시제를 혼합하여 광경화 및 알칼리 현상이 가능한 수지조성을 기반으로 은 분말을 첨가하여 감광성 Ag 페이스트를 제조하였다. 구형 은 분말의 함량이 증가할수록 전도성 입자간 밀집도가 좋아져 비저항(volume resistance) 값은 낮아졌으며, 88 wt%의 구형 은 분말을 함유한 페이스트는 1.14×10SUP-4/SUP Ω·cm의 값을 나타내었다. 구형과 판상형 은 분말을 8:2의 비로 혼합하였을 때 84 wt%로 은 분말의 함량을 줄였음에도 불구하고 비저항은 7.04×10SUP-5/SUPΩ·cm로 가장 우수한 값을 보였다. 이 결과는 판상형 은 분말이 구형 분말 사이의 전도성 연결을 개선하여 전기가 흐르기 용이하도록 만들어 주었기 때문이다.

In-House Development of Shear Horizontal Acoustic Waves Based Sensitive Sensors for Bacterial Pathogens Detection

Surface acoustic wave can be generated at the free surface of an elastic solid. Interdigital transducers (IDTs) are fabricated on the piezoelectric substrate surface that will act as electrical input and output port. When appropriate AC voltage stimulus is applied to the input transducer, surface acoustic wave will be produced. The output or receiving port will detect the incident surface acoustic wave and convert it back to a suitably filtered electrical once. For this property, surface acoustic based devices were initially developed for the telecommunication purpose such as signal filters and resonators. SAW based devices have been modified to be sensors later on from for gas detections and have been moving towards biological detections recently for its ultra-sensitivity to surface perturbation. The main component of this device is the IDTs. Recently, there are several methods to produce IDTs; Ultra-Violet (UV), deep UV lithography, Electron beam (e-beam) lithography and X-ray lithography. Although, these methods can produce very fine and accurate electrodes in term of submicron size but the costs are extremely expensive. Thus, this paper will discuss the conventional CMOS method which is much more economical to produce the applicable IDTs for the bacterial pathogens sensing purpose. Shear horizontal surface acoustic wave (SHSAW), one of the SAW based types is used in this paper as it is most suitable for the liquid based application as it has the advantage of acoustic energy is not being radiated into liquid.

Electrochemical Reduction of Carbon Dioxide on Single-Crystal Copper Membrane

The electrochemical reduction of carbon dioxide (CO2) on copper electrodes has been attracting great interest as an intermittent CO2 conversion system, which can synthesize hydrocarbons at room temperature and under ambient pressure. Many extensive efforts clarified the synthesis mechanism of hydrocarbons in the electrochemical reduction of CO2[1-2]. Recent progress of the selective synthesis utilizing the crystal structure on a copper electrode offers a promising route to produce the desired hydrocarbon product. Although this system converts CO2 to hydrocarbons effectively, it is difficult to construct the manufacturing process because a large-area single crystal electrode is expensive. In practice, the past efforts were almost utilized a fine single crystal electrode, such as bead or rod. In this research, we reports the electrochemical reduction of CO2 on a ”large-area” single crystal copper membrane epitaxially deposited on sapphire and magnesium oxide (MgO) as a support substrate. In the experiments, copper membranes were deposited onto glass, c-plane sapphire, and MgO substrates in argon atmosphere by the radio frequency magnetron sputtering machine. A series of copper membranes were characterized by X-ray diffraction (XRD) analysis to confirm the copper crystal structure. Figure 1 shows the experimental results, where the commercial copper plate (Aldrich, 1.0 mm thick 99.999% purity) and the copper membrane deposited on the glass substrate have three peaks of the crystal structure, Cu(111), Cu(100), and Cu(110). On the other hand, copper membranes deposited on c-plane sapphire, MgO(100) and MgO(110) substrate are highly crystalline with Cu(111), Cu(100), and Cu(110), respectively. This suggests that the copper membranes epitaxially grew along a crystal structure on the single crystal support substrates. The electrochemical reduction of CO2 on the single crystal copper membranes was performed in an electrochemical cell with a three-electrode assembly at room temperature and ambient pressure. Figure 2 shows the time dependence of the methane concentration in the effluent gas on Cu(111) membrane and the commercial copper plate as electrodes, respectively. Only a trace amount of ethylene was observed with the concentration of < 1 ppm. It is noted that the methane emission is strongly dependent on the crystalline of the copper electrode. Moreover, significantly higher CO2 conversion in sodium hydroxide (NaOH) electrolyte (pH=13.8) than that in phosphate buffer (pH=7.2) was observed on Cu(111) membrane. The electrochemical conversion of CO2 to methane reveals to be favored in strong alkali electrolyte. However, methane concentration in this electrolyte decreased with the electrolyte pH drop during electrochemical reduction (pH=13.8→7.4), which is accounted for by the neutralization between CO2 and NaOH. We will also show the electrochemical reduction of CO2 on another copper crystal structure, and the electrochemical mechanism based on dissolved carbon oxide concentration in the electrolyte discussed. Acknowledgement This work is supported by the Sasakawa Scientific Research Grant from The Japan Science Society and the Shiraishi Scientific Research Grant. Reference [1] Y. Hori, I. Takahashi, O. Koga, N. Hoshi, “Electrochemical reduction of carbon dioxide at various series of copper single crystal electrodes”, Journal of Molecular Catalysis A: Chemical, 2003, 199, 39–47. [2] K. J. P. Schouten, E. P. Gallent, and M. T. M. Koper, "Structure Sensitivity of the Electrochemical Reduction of Carbon Monoxide on Copper Single Crystals", ACS Catal., 2013, 3, (6), 1292–1295. Figure 1. XRD profiles of copper electrode in this study. (a)commercial copper plate, (b)copper membrane on glass substrate, (c)copper membrane on c-sapphire substrate, (d)copper membrane on MgO(100) substrate, (e)copper membrane on MgO(110) substrate. Figure 2. Methane concentration curves plotted as function of reaction time for the electrochemical reduction of CO2 on Cu(111) membrane and Cu plate at an electrode potential of -0.9 V vs. RHE. Figure 1

Inter-electrode charge collection in high-purity germanium detectors with amorphous semiconductor contacts

High-purity germanium (HPGe) radiation detectors with segmented signal readout electrodes combine excellent energy resolution with fine spatial resolution, opening exciting possibilities in radiation imaging applications. Segmenting the electrodes provides the ability to determine the positions of radiation interactions in the detector, but it also brings potential challenges that can inhibit performance. A challenge unique to segmented electrode detectors is collection of charge carriers to the gap between adjacent electrodes rather than to the electrodes themselves, which gives a deficit in the summed energy. While amorphous semiconductor electrical contacts have enabled a simplified fabrication process capable of fine electrode segmentation, the amorphous semiconductor passivation layer between electrodes is prone to inter-electrode charge collection. This article presents a study of the impact of fabrication process parameters on the energy deficit due to inter-electrode charge collection for double-sided strip detectors. Eight double-sided strip HPGe detectors were fabricated with amorphous germanium (a-Ge) and amorphous silicon (a-Si) contacts formed by sputter deposition. Each detector was evaluated for inter-electrode charge collection performance, using as a metric the deficit in the summed signal of two adjacent electrodes. It is demonstrated that both a-Ge and a-Si contacts can be produced with nearly non-existent inter-electrode charge collection when the appropriate combination of sputter gas hydrogen content and gas pressure are selected.

Preparation of La2NiO4+δ powders as a cathode material for SOFC via a PVP-assisted hydrothermal route

Uniform submicron La2NiO4+δ (sm-LNO) powders have been synthesized by a facile polyvinylpyrrolidone (PVP)-assisted hydrothermal route. In the presence of PVP, sm-LNO of pure phase has been obtained by calcination at the relatively low temperature of 900 °C for 8 h. Compared micron-sized LNO (m-LNO) particles obtained at 1,000 °C by hydrothermal synthesis route without PVP assisted, the sm-LNO-PVP displays regularly shaped and well-distributed particles in the range of 0.3–0.5 μm. The scanning electron microscopy (SEM) results showed that the sm-LNO sample is submicronic and that the m-LNO sample shows agglomerates with a broad size distribution. The electrochemical performance of m-LNO and sm-LNO-PVP has been investigated by electrochemical impedance spectroscopy. The polarization resistance of the sm-LNO-PVP cathode reaches a value of 0.40 Ω cm2 at 750 °C, which is lower than that of m-LNO (0.62 Ω cm2). This result indicates that a fine electrode microstructure with submicron particles can help to increase the active sites, accelerate oxygen diffusion, and reduce polarization resistance. An anode-supported single cell with sm-LNO cathode has been fabricated and tested over a temperature range from 650 to 800 °C. The maximum power density of the cell has achieved 834 mW cm−2 at 750 °C. These results therefore show that this PVP-assisted hydrothermal method is an effective approach to construct submicron-structured cathode and enhance the performance of intermediate temperature solid oxide fuel cell.

Sulfur-based composite cathode materials for high-energy rechargeable lithium batteries.

There is currently an urgent demand for highly efficient energy storage and conversion systems. Due to its high theoretical energy density, low cost, and environmental compatibility, the lithium sulfur (Li-S) battery has become a typical representative of the next generation of electrochemical power sources. Various approaches have been explored to design and prepare sulfur cathode materials to enhance their electrochemical performance. This Research News article summarizes and compares different sulfur materials for Li-S batteries and particularly focuses on the fine structures, electrochemical performance, and electrode reaction mechanisms of pyrolyzed polyacrylo-nitrile sulfur (pPAN@S) and microporous-carbon/small-sulfur composite materials.

Electromyography of swallowing with fine wire intramuscular electrodes in healthy human: activation sequence of selected hyoid muscles.

Few studies have reported the activation sequence of the swallowing muscles in healthy human participants. We examined temporal characteristics of selected hyoid muscles using fine wire intramuscular electromyography (EMG). Thirteen healthy adults were studied using EMG of the anterior belly of digastric (ABD), geniohyoid (GH), sternohyoid (SH), and masseter (MA, with surface electrodes) while ingesting thin liquid, banana, tofu, and cookie (3 trials each). Onset timing was measured from rectified and integrated EMG. Data were analyzed using repeated-measures ANOVA with Bonferroni correction. When drinking thin liquid, MA, GH, and ABD were activated almost simultaneously, but SH was activated later (using GH onset as 0 s, MA -0.07 (-0.20 to 0.17) second [median (interquartile range)]; ABD 0.00 (-0.10 to 0.07) second; SH 0.17 (0.02 to 0.37) second; P < 0.01). With solid foods, MA contraction preceded GH and ABD; SH was last and delayed relative to liquid swallows (GH 0 s; MA -0.17 (-0.27 to 0.07) second; ABD 0.00 (-0.03 to 0.03) second; SH 0.37 (0.23 to 0.50) second; P < 0.01). The role of the MA differs between solids and liquids so the variation in its timing is expected. The synchronous contraction of GH and ABD was consistent with their role in hyolaryngeal elevation. The SH contracted later with solids, perhaps because if the longer duration of the swallow. The consistent pattern among foods supports the concept of a central pattern generator for pharyngeal swallowing.

Performance Characteristics of CZT Detectors for PET Imaging Applications

Positron emission tomography (PET) is a non-invasive, in-vivo, imaging technology that plays a critical role in cancer detection, as well as in molecular and cellular imaging. For PET imaging, and attractive alternative to a scintillator and photomultiplier assembly (PMT) is the Cadmium Zinc Telluride (CZT) detector. Th CZT and other detectors have recently attracted extensive research interests in the development of novel PET imaging systems [1, 2]. The benefits of CZT include relatively high atomic number, density, large band-gap energy, high spatial resolution through fine electrodes, and superior energy resolution for 511 keV photons due to direct charge carrier generation/collection rather than indirect process of scintillation photon emission as in the scintillator and PMT module. In addition, it has shown great promises to be used as a 3D positioning detector by incorporating depth-of-interaction (DOI) resolution of CZT, which can help mitigate parallax error in PET systems.In this work, we developed an analytical model to study the charge collection and temporal behavior, which is expected to assist to optimize a number of design parameters including anode/cathode electrode pitch, steering electrode pitch and voltage bias.Two common electrode configurations (pixilated and cross strip) for CZT detectors are shown in Fig. 1. When a 511 keV gamma ray hits the detector, a number of electron-holes are generated and travel within the internal electric field E. As stated by Shockley–Ramo theorem [3], the induced charge q(t) builds up as the electron-hole pairs moves from position r1 to r2, which can be written as q(t)=q0(Φω(r2)-Φω(r1))，where q0 is the elementary charge of electron, Φω is the weighting potential. To model the temporal dependency that impacts the time resolution, the drift time te,h of Δx distance is te,h= Δx/μe,hE, where μe,hare charge carries mobility.For validation, we assemble two CZT detectors (Redlen, Canada) as shown in Fig. 1. For the cross-strip one, the cathodes orient orthogonally to the anodes, to provide spatial information in two dimensions. The detectors were biased at 400 V. After preamplifier and shaping amplifier circuits, the outputs were connected to a high-speed free running ADC (CAEN, sampling rate 500MS/s, dynamic range 1V) to measure energy spectrum.The simulations and experimental results are illustrated in Fig. 2. The weighing potential has a pattern as shown in Fig. 2c, which is low near the cathode and rises rapidly when close to the anode. Such pattern is associated with the small pixel effect and single polarity sensing techniques, which affects both charge collection and temporal response of CZT detectors, as the function of different a/L ratio (pixel size to detector thickness). As a/L ratio decreases, the weighting potential shows a more abrupt change towards the anode region, which implies that the incomplete charge collection can be mitigated [4].The normalized charge collection, q(t)/q0, as a function of normalized time t/Th (Th is the maximum hole transit time through detector thickness L) for three heights is shown in Fig. 2d, where the sharp rising presents the electrons’ motion, and the flat trend presents the holes’ motion. A1 point has the best charge collection effective and the rising time is about 0.12Th; Points A2 and A3 are farther away from cathode due to poor hole mobility, so a longer collect time are needed (0.68Th and 0.82Th respectively), which means for CZT non-uniform responses are occurred in different depths, which can be used to obtain DOI information. While, for cross section of CZT (A2, B2, C2), the charge signal are more uniform as shown in Fig. 2e.The energy resolution is ~2.98±0.26% FWHM for 511 keV as shown in Fig. 2f, which is superior compared the typical value of 15-20% of a scintillation and PMT model. This result is based on a collimated beam of 511 keV gamma ray irradiating the whole pixel entering from the cathode side (i.e., interaction at all heights are included). In our future work, we will translate the beam along the Z direction to validate the detector performances again the analytical modeling. Reference [1] Hao Peng and Craig S Levin. “Design study of a high-resolution breast-dedicated PET system built system built from cadmium zinc telluride detectors”, Phys. Med. Biol., 55, pp. 2761-2788, 2010.[2] D Palubiak, MM El-Desouki, O Marinov, MJ Deen, Q Fang, “High-speed, single-photon avalanche-photodiode imager for biomedical applications”, IEEE Sensors Journal, 11, pp. 2401-2412, 2011.[3] S. Ramo, “Currents Induced by Electron Motion” Proc. IRE. 27, pp. 584-585, 1939.[4] Barrett, H.H. et al., “Charge Transport in Arrays of Semiconductor Gamma-Ray Detectors”,Phys. Rev. Lett, pp. 156-159, 1995

Effect of Micro-EDM on Diameter Consistency of Micro-Hole Arrays

The inkjet template is an important part of digital printing equipment. The diameter of hole arrays on the template determines the consistency of the ink droplet and thus affects print quality. To improve the printing performance of digital printing equipment, this study investigated the effect of micro-electrical discharge machining (micro-EDM) on the diameter consistency of micro-hole arrays on an inkjet template. Combining block electrical discharge grinding and wire electrical discharge grinding enabled the online processing of the fine tool electrode, whose diameter can be stably controlled at less than 45 μm, whose maximum diameter deviation was about 1 μm. The tool electrode can also be used to process micro-hole arrays. Subsequently, the relationship between the discharge energy of micro-EDM and the erosion material was theoretically analyzed, as was the effects of the diameter consistency of the micro-electrode itself on that of the micro-hole array processed by the micro-electrode and the relationship between processing parameters and the discharge gap between the micro-electrode and the workpiece. Experimentations were conducted on the effect of the flow rate, flush angle, and rotation speed of the electrode and the resistivity of de-ionized water to the diameter consistency of the micro-hole arrays. On the optimized parameters, a 16×16 micro-hole array with a diameter deviation of less than 2 μm was successfully processed, and the average diameter of the holes, about 44 μm, was used for the inkjet template. Beside, an electrode with a diameter of 14μm is also machined and it was used to process a 8×8 micro-hole array, whose diameter deviation is 0.9μm and average diameter is less than 20μm. Large number of experiments show that by the proposed method, one electrode can stably machined 800 holes with diameter less than 50μm, and their diameter deviation is less than 3μm. ​The digital printing equipment with these holes can meet the current demand for components with micro-hole arrays.

Experimental study of fine center electrode spark plug in bi-fuel engines

In the present work, the erosion of platinum fine center electrode spark plugs and conventional nickel plugs are investigated in a gasoline and natural gas bi-fuel engine. The effect of electrode erosion is evaluated by comparing the required ignition voltage and cold start ability of the different plug designs. After durability tests, platinum fine center electrode plug had insignificant electrode erosion and negligible gap growth; whereas the nickel plug had notable erosion and gap growth. There was no detectable side sparking for fine center electrode plugs. In terms of performance, the required ignition voltage of fine center electrode plug was lower than conventional spark plug. Also, results of a cold start test demonstrated that the starting time of the engine with fine electrode plugs was lower than conventional spark plugs. The surface of electrodes was studied by the scanning electron microscope and the energy dispersive X-ray spectroscopy techniques. Cracking and peeling was observed on the surface of the nickel conventional electrodes, but not on the surface of the platinum fine electrodes. These tests show that platinum fine center electrodes could be suitable for gasoline/natural gas bi-fuel engines to meet long lifetime demand.

Linear resonant electrostatic induction motor using electrical resonance with piezoelectric transducers

This paper proposes an electrostatic linear induction motor resonating electrically with piezoelectric transducers. The motor is based on an electrostatic film motor composed of two thin plastic films containing fine pitch three-phase electrodes, which face each other across a short gap. The motor requires three-phase high voltages on the electrodes in both films to obtain thrust force. Our proposal in this paper is to utilize piezoelectric transducers to realize the high voltage on one of the films: the slider film, by using the transducers as inductive elements that resonate with the electrostatic motor. We describe specific design method of the piezoelectric transducers for this application, and analyze the influences of their properties on the performance of the motor. A working prototype was constructed with piezoelectric length-extensional bars as the transducers. The prototype demonstrated a maximum thrust force of 0.24N with 500V0-p three-phase excitation. When driven at high voltages, we observed a step-like motion caused by a non-linear behavior of the piezoelectrics, i.e., the jump resonance. The observation indicates a problem in optimal design of the piezoelectric transducers for this specific application.

Sympathetic Nervous System Moves Toward Center Stage in Cardiovascular Medicine

In 1664, the first anatomically correct depiction of the sympathetic nervous system came from Thomas Willis and his circle of London anatomists,1 included in The Anatomy of the Brain and Nerves , 1664 (Figure 1). This, the first work dedicated completely to the nervous system, also described the arterial loops at the base of the brain, which we now know as the Circle of Willis.1 Christopher Wren, an anatomist member of the group, was the principal illustrator1 before being asked by the City Fathers to turn his talents to town planning, architecture, and cathedral building after the 1666 Great Fire of London. Figure 1. An illustration of the human sympathetic nerves of the neck and thorax, from The Anatomy of the Brain and Sympathetic Nerves , published in 1664 by Thomas Willis and reproduced in Soul Made Flesh .1 Almost 2 centuries later, subsequent microscopic examination demonstrated that blood vessel walls were densely innervated, leading Stelling in 18402 to correctly conclude that these vasomotor fibers were in fact sympathetic nerves that were carried from the central nervous system to the blood vessels. In the mid-19th century, celebrated European physiologists, including Brown-Sequard, Waller, and Bernard,2 built on these observations, demonstrating vasoconstriction with electrical stimulation of the cut nerves and vasodilatation on nerve section, which indicated that the sympathetic fibers exerted a tonic, vasoconstrictor influence. The pressor nerves had gained recognition. Identification of the sympathetic neurotransmitter proved to be difficult. Claims for epinephrine3,4 and the hypothetical sympathins I and E confused the picture. Ulf von Euler compared bioassay responses of epinephrine, norepinephrine, and dihydroxy norephedrine with those of cattle splenic nerve extract, by testing blood pressure (BP) responses in the anesthetized cat and contractile responses in the isolated pregnant rabbit uterus, to definitively demonstrate the …

S0550102 表面微細電極構造を有するDBDプラズマアクチュエータに関する実験的研究([S055-01]プラズマアクチュエータ(1))

S0550102 表面微細電極構造を有するDBDプラズマアクチュエータに関する実験的研究([S055-01]プラズマアクチュエータ(1))

Analysis Electroencephalogram Signals Using ANFIS and Periodogram Techniques

In this paper the applications the Adaptative Neuro Fuzzy Inference Systems (ANFIS), the Empirical Mode Decomposition (EMD) and Discrete Wavelet Distribution (DWT) are used. An electroencephalogram (EEG) is a diagnostic test which measures the electrical activity of the brain using highly sensitive recording equipment attached to the scalp by fine electrodes. An EEG recording is often affected with noises. These noises strongly affect the visual analysis of EEG. To overcome this problem the denoising techniques as ANFIS, EMD and DWT are applied. The efficiency of the ANFIS, EMD and DWT to remove the noises was evaluated by several standard metrics between filter EEG output and clean original signal. The results obtained show that the ANFIS outperformed other denoising techniques in terms of localization of the components of the abnormal EEG signal. Due to non-stationary nature of the EEG signal, the uses of time-frequency techniques are inevitable. The parametric time-frequency technique used is Periodogram (PE). The EEG signals used are normal and abnormal; the abnormal signals are obtained from the patient that has the sleep-disordered breathing (SDB) and the patient that has the sleep movement disorders (periodic leg movements or PLM). The PE technique shows its higher performance at the level of resolution and deleting any interference-terms over other non-parametric time-frequency techniques given in the scientific literature. This study demonstrates that the combination of ANFIS and the PE techniques are a good issue in the in biomedicine. For experimental study we have used the MIT/BIH arrhythmia database. Simulations were carried out in MATLAB environment.

폴리머 다이렉트 그라비어 인쇄법에 의한 미세패턴 전극 개발

폴리머 다이렉트 그라비어 인쇄법에 의한 미세패턴 전극 개발

Fabrication of metal electrodes on flexible substrates by controlled deposition of conductive nano-ink

In this study, a novel process was developed for the fabrication of ultrafine electrodes on flexible substrates. Conductive fine electrodes using silver nano-ink on polyimide (PI) film were obtained by means of plasma-enhanced superhydrophobic technology. The plasma etching conditions were optimized for the formation of a superhydrophobic layer on the surface of the PI film. A micro-trench on the hydrophobic PI film was then formed by mechanical scratching, thus imparting hydrophilic properties only to the trench area. Finally, the fine electrode was realized by the selective deposition of aqueous silver nano-ink on the trench region. The electrical properties of the conductive electrodes fabricated using silver nano-ink with an average particle size of 50 or 200nm were investigated and the microstructure of the electrodes was observed using an electron microscope at sintering temperatures ranging from 150 to 400°C. In addition, the addition effect of silver nanowire to silver nano-ink was examined to assess the improvement on the conductive properties of electrode.