• Title/Summary/Keyword: electronic needle

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Novel dental anesthetic and associated devices: a scoping review

  • Kyung Hyuk Min;Zac Morse
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.24 no.3
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    • pp.161-171
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    • 2024
  • The efficient management of pain and discomfort is essential for successful dental treatment and patient compliance. Dental professionals are commonly evaluated for their ability to perform treatment with minimal patient discomfort. Despite advancements in traditional local dental anesthesia techniques, the pain and discomfort associated with injections remain a concern. This scoping review aims to provide a comprehensive overview of the literature on novel dental anesthetics and associated devices designed to alleviate pain and discomfort during dental procedures. The Joanna Briggs Institute and the Preferred Reporting Items for Systematic reviews and Meta-Analyses Extension for Scoping Reviews guidelines were used to prepare the review. Six databases and two sources of gray literature were searched. This review analyzed 107 sources from 1994 to 2023. Local anesthesia devices were grouped into computer-controlled local anesthetic delivery (CCLAD) systems, intraosseous anesthesia (IOA), vibratory stimulation devices, and electronic dental anesthesia (EDA). CCLAD systems, particularly the Wand and Single-Tooth Anesthesia, have been the most researched, with mixed results regarding their effectiveness in reducing pain during needle insertion compared to traditional syringes. However, CCLAD systems often demonstrated efficacy in reducing pain during anesthetic deposition, especially during palatal injections. Limited studies on IOA devices have reported effective pain alleviation. Vibrating devices have shown inconsistent results in terms of pain reduction, with some studies suggesting their primary benefit is during needle insertion rather than during the administration phase. EDA devices are effective in reducing discomfort but have found limited applicability. These findings suggest that the CCLAD systems reduce injection pain and discomfort. However, the evidence for other devices is limited and inconsistent. The development and research of innovative technologies for reducing dental pain and anxiety provides opportunities for interdisciplinary collaboration and improved patient care in dental practice.

Ferroelastic Domain Wall Motions in Lead Zirconate Titanate Under Compressive Stress Observed by Piezoresponse Force Microscopy

  • Kim, Kwanlae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.30 no.9
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    • pp.546-550
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    • 2017
  • Ferroelectric properties are governed by domain structures and domain wall motions, so it is of significance to understand domain evolution processes under mechanical stress. In the present study, in situ piezoresponse force microscopy (PFM) observation under compressive stress was carried out for a near-morphotropic PZT. Both $180^{\circ}$ and $non-180^{\circ}$ domain structures were observed from PFM images, and their habit planes were identified using electron backscatter diffraction in conjunction with PFM data. By externally applied mechanical stress, needle-like $non-180^{\circ}$ domain patterns were broadened via domain wall motions. This was interpreted via phenomenological approach such that the total energy minimization can be achieved by domain wall motion rather than domain nucleation mainly due to the local gradient energy. Meanwhile, no motion was observed from curvy $180^{\circ}$ domain walls under the mechanical stress, validating that $180^{\circ}$ domain walls are not directly influenced by mechanical stress.

The Transient Phenomena of Fuel Injection Nozzle for Electronic Control SI Engines (SI 機關용 電子制御 燃料噴射노즐의 過渡的 現象)

  • 김신구;김덕줄;이충원
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.2
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    • pp.308-318
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    • 1988
  • The liquid disintegration and characteristics of atomization through the swirl nozzle is affected by injection pressure and injection time when the liquid is injected intermittently. These transient phenomena are investigated by electronic controlled-fuel injection nozzle. The effect of injection conditions on disintegration of liquid injected through nozzle is observed photographically by using delay circuit. Droplet size of the element of the sample is measured by the liquid immersion sampling technique. SMD of droplets is varied with time and is decreased as the injection pressure increases. As the injection pressure increases, the maximum diameter of droplet and diameter of droplet which has the maximum droplet number decrease. Spray angle is not affected on injection pressure and change of spray angle with time is associated with needle movement.

Dielectric Behaviors and Prebreakdown Phenomena of $SF_{6}$ Gas in Inhomogeneous Field Caused by a Conducting-Particle

  • Lee, Bok-Hee;Kil, Gyung-Suk;Lee, Chang-Jun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.05a
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    • pp.204-207
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    • 1995
  • This paper deals with the dielectric characteristics of $SF_{6}$ gas stressed by non-oscillating and oscillating impulse voltages in inhomogeneous field perturbed by a fixed needle shaped-protrusion. The breakdown voltage-time characteristics were measured for both polarities and over the gas pressure range from 0.1 to 0.5 [MPa], and the temporal developments of the prebreakdown were observed. The dependence of the leader stepping time on the gas pressure were obtained.

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PD Characteristic of Electrical Tree Generated by Inside Void Defect (내부 보이드 결함에서 발생하는 전기트리의 부분방전 특성)

  • Park, Seong-Hee;Jung, Hae-Eun;Kang, Seong-Hwa;Lim, Kee-Jo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2006.11a
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    • pp.334-335
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    • 2006
  • Solid insulation exposed to voltage is degraded by electrical tree process. And the degradation of the insulation is accelerated by voltage application. For this experimental, specimen of electrical tree model is made by XLPE (cross-linked polyethylene). And the size of the specimen is 7*5*7 $mm^3$. Distance of needle and plane is 2 mm. Voltages applied for acceleration test are 12 kV to 15 kV. And distribution characteristic of degraded stage is studied too. As a PD detecting and data process, discharge data acquire from PD detecting system (Biddle instrument). The system presents statistical distribution as phase resolved. Moreover the processing time of electrical tree is recorded to know the speed of degradation according to voltage.

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NAC Measurement Technique on High Parallelism Probe Card with Protection Resistors

  • Kim, Gyu-Yeol;Nah, Wansoo
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.5
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    • pp.641-649
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    • 2016
  • In this paper, a novel time-domain measurement technique on a high parallelism probe card with protection resistors installed is proposed. The measured signal amplitude decreases when the measurement is performed by Needle Auto Calibration (NAC) probing on a high parallelism probe card with installed resistors. Therefore, the original signals must be carefully reconstructed, and the compensation coefficient, which is related to the number of channel branches and the value of protection resistors, must be introduced. The accuracy of the reconstructed signals is analyzed based on the varying number of channel branches and various protection resistances. The results demonstrate that the proposed technique is appropriate for evaluating the overall signal performance of probe cards with Automatic Test Equipment (ATE), which enhances the efficiency of probe card performance test dramatically.

The Diagnosis of Treeing Breakdown Using Simultaneous Detection of Electrical Charge and Acoustic Emission Pulse of Partial Discharge (부분 방전 전하와 음향 방출 펄스의 동시 측정에 의한 트리잉 파괴 진단)

  • 김성홍;박재준;김재환
    • Electrical & Electronic Materials
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    • v.10 no.3
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    • pp.247-254
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    • 1997
  • Internal voids in insulators give rise to partial discharge, which causes a local breakdown and even entire insulation breakdown. Recently, the necessity of establishing the way to diagnose the aging of insulation materials and to predict of insulation breakdown become important. The purpose of our work are to investigate the treeing phenomena with an artificial needle shaped void by the charge of discharge and acoustic emission pulse in each phase angle area at the same time. We analyzed the .PHI.-QA-t pattern and .PHI.-AEA-t pattern using statistic operators such as pulse magnitude, pulse number, skewness, kurtosis. Therefore, the relation between the charge of discharge and acoustic emission pulse will be helpful to predict the breakdown just before the breakdown occur.

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Breakdown characteristics with temperature variation on XLPE 6.9kV cable insulator at power plants (발전소 6.9kV급 XLPE 케이블 절연재의 온도에 따른 절연파괴 특성분석)

  • Park, Noh-Joon;Yang, Sang-Hyun;Lee, Ki-Joung;Kong, Tae-Sik;Kim, Hee-Dong;Park, Dae-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.06a
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    • pp.79-79
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    • 2010
  • In this paper, we present results of the dielectric breakdown test in various 6.9kV power cables used in power plants. The dielectric strength of the different conditioned cables was measured by placing the sliced cable sections in silicone oil bath with needle electrode. The results were analyzed by the Weibull distribution. The shape and scale parameters of the Weibull distribution for each cable sections under test were calculated and evaluated. Collected data base was applied to deterioration trend analysis and lifetime guide was also proposed.

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characteristic of breakdown voltage of electrode gap in vacuum (진공에서 극간 gap에 따른 절연파괴 전압 특성 파악)

  • Yoon, Jae-Hun;Kim, Byung-Chul;Lee, Sueng-Su;Lim, Kee-Jo;Kang, Seong-Hwa
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.11a
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    • pp.366-367
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    • 2008
  • SF6 widely used as insulating gas is rising as the environment problem. For decreasing this greenhouse gas, electrical breakdown characteristics of vacuum with air are studied in non-uniform field. The gap of needle to plane was 0.5mm, 0.8mm. The pressure of vacuum the range of 10^-4-10^-5torr. The diameter of a plane made of the stainless steel is150mm. As a result of the experiment, the breakdown voltage is increased about electrode gap distance increased. The electrode material influenced breakdown voltage in vacuum.

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Preparation and Characteristics of Transparent Anti-static Films (투명 대전방지 필름 제조 및 특성)

  • 김종은;심재훈;서광석;윤호규;김명화;황공현
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.1
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    • pp.52-59
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    • 2000
  • In order to develop the transparent anti-static film with higher than 80% transparency to visible light, organic conductive compounds, N-methyl phenazinium 7,7,8,8-tetracyanoquinonedimethane (TCNQ) com-plex salts was synthesized and bar-coated on the polythylene terephthalate (PET) film using polymer binders. The best surface properties were obtained when acrylic binder was used. A single layer of TCNQ made of a acrylic binder showed a surface resistance of 10\ulcorner $\Omega$/ , a conductivity of 10\ulcorner S/cm, and a transparency of 75%. An optical microscopic examination revealed that the binder was first solidi-fied on the surface of PET film over which the needle-shaped TCNQ crystals were grown. An acrylic polyol coating over the TCNQ layer improved the transparency to 87%, becuase the acrylic polyol covers the surface of TCNQ crystals to reduce the surface roughness. This conductive material has thermal stability at room temperature and 4$0^{\circ}C$ over 4,000 h.

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