• Title/Summary/Keyword: streaming potential

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A Study on the Electrification Phenomena Affecting Industrial Disaster (산업재해에 미치는 대전현상에 관한 연구)

  • 육재호;안병준
    • Journal of the Korean Society of Safety
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    • v.8 no.4
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    • pp.101-106
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    • 1993
  • The streaming current of insulating oil increases with increasing oil velocity and oil amount, A contact potential difference as an energetic state exits in the polymer thin film, both sides of which are contacted by two different metals having different work functions. Accordingly, the potential difference may be a cause for the short circuited transient current flowing through the external circuit. The polymers are electrificated as the electric field Is supplied, and the currents flow with increasing temperature.

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Zeta-potential Measurement on Glass Surface by Measuring Electro-osmotic Velocity inside a Micro-channel (마이크로 채널 내부 전기삼투 유속 측정을 통한 유리표면의 Zeta-potential 측정)

  • Han, Su-Dong;Lee, Sang-Joon
    • 한국가시화정보학회:학술대회논문집
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    • 2005.12a
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    • pp.80-84
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    • 2005
  • Many important properties in colloidal systems are usually determined by surface charge ($\zeta$-potential) of the contacted solid surface. In this study, $\zeta$-potential of glass $\mu$-channel was evaluated from the electro-osmotic velocity distribution. The electro-osmotic velocity inside a glass $\mu$-channel was measured using a micro-PIV velocity field measurement technique. This evaluation method is more simple and easy to approach, compared with the traditional streaming potential technique. The $\zeta$-potential in the glass $\mu$-channel was measured for two different mole NaCl solutions. The effect of an anion surfactant, sodium dodecyl sulphate (SDS), on the electro-osmotic velocity and $\zeta$-potential in the glass surface was also studied. In the range of $0\∼6$mM, the surfactant SDS was added to NaCl solution in four different mole concentrations. As a result, the addition of SDS increases $\zeta$-potential in the surface of the glass $\mu$-channel. The measured $\zeta$-potential was found to vary from-260 to-70mV. When negatively charged particles were used, the flow direction was opposite compared with that of neutral particles. The $\zeta$-potential has a positive sign for the negative particles.

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Measurement of Zeta-potential of Electro-osmotic Flow Inside a Micro-channel (마이크로 채널 내부 전기삼투 유동의 Zeta-potential 계측)

  • Han Su-Dong;Lee Sang-Joon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.10 s.253
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    • pp.935-941
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    • 2006
  • Many important properties in colloidal systems are usually determined by surface charge $({\zeta}-potential)$ of the contacted solid surface. In this study, ${\zeta}-potential$ of glass ${\mu}-channel$ was evaluated from the electro-osmotic velocity distribution. The electro-osmotic velocity inside a glass f-channel was measured using a micro-PIV velocity field measurement technique. This evaluation method is more simple and easy to approach, compared with the traditional streaming potential technique. The ${\zeta}-potential$ in the glass ${\mu}-channel$ was measured fur two different mole NaCl solutions. The effect of an anion surfactant, sodium dodecyl sulphate (SDS), on the electro-osmotic velocity and f-potential in the glass surface was also studied. In the range of $0{\sim}6mM$, the surfactant SDS was added to NaCl solution in few different mole concentrations. As a result, the addition of SDS increases ${\zeta}-potential$ in the surface of the glass ${\mu}-channel$. The measured $\zeta-potential$ was found to vary from -260 to -70mV. When negatively charged particles were used, the flow direction was opposite compared with that of neutral particles. The ${\zeta}-potential$ has a positive sign for the negative particles.

Distributed Cache to Support Video-on-Demand Service over P2P Network

  • Ren, Jian-Ji;Lee, Jae-kee
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.765-768
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    • 2007
  • P2P Video-on-Demand (VoD) is becoming a popular service in the Internet. The first deployments are already in place, and millions of customers worldwide are already using this new medium. But its success is still quite limited and technically, these researches have been deployed in a rush, mostly based on practicality and instability. This paper studies the advantages and potential problems of VoD in peer-to-peer (P2P) network, we propose a system which uses a distributed VoD streaming scheme over P2P network to support media streaming.

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A Study on charge accumulation and relaxation phenomena by D.C energization in insulating oil (직류 전계 인가에 따른 절연유의 전하 축적 및 완화 현상에 관한 연구)

  • Kim, C.W.;Lim, H.C.;Kim, Y.W.;Shin, T.H.;Huh, C.S.;Lee, D.C.
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1633-1635
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    • 1996
  • This phenomena of streaming-electrification is generated between solid and liquid boundary called electric double-layer which is generated by potential difference. A charge separation at interfaces between a moving fluid and a solid boundary can give rise to the generation of substantial electric field and at last these can give rise ta insulating failure. Therefore injection of the adverse-charge in streaming-electrified insulating oil to eliminate the accumulation charge and its related phenomena was investigated.

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Case Study on the Electrostatic Hazards in the Coating Mechanical System (도장설비에서의 정전기 재해 사례 연구)

  • Kim, Gil-Tae;Jung, Young-Man;Lee, Jae-Keun
    • Proceedings of the SAREK Conference
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    • 2006.06a
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    • pp.602-606
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    • 2006
  • The electrostatic is well known phenomena. The fires and explosions caused by electrostatic occur often in the coating mechanical system. This paper presents various cases of electrostatic hazards, reasons why electrostatic hazards are happened, and methods for preventing electrostatic hazards. Generally the electrostatic can be lead to corona discharging, streaming electrification, and impinging electrification in the coating process. Corona discharging happens at electrostatic spray gun with 70 kV. Streaming electrification occurs at mixing process between paint and thinner, and transportation process with thinner. Impinging electrification is shown when the thinner are sprayed to drums. For the purpose of preventing the electrostatic discharge and damage, conductors should be ground, surface electric potential of should be decreased in using electrostatic shielding and ground, and flow of thinner should be controlled acceptable velocity.

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The Impact of Blockchain Technology on the Music Industry

  • Kim, Kenneth Chi Ho
    • International journal of advanced smart convergence
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    • v.8 no.1
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    • pp.196-203
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    • 2019
  • We have reviewed the potential impact of blockchain technology on the music industry by analyzing the views of academia and the industry experts. The music industry had rapid changes from the physical market to the digital market in the past decades. The consumers download and stream music online and mobile during the digital dominant market. While streaming music has been recently growing at a fast rate, fair distribution of revenue to the artists continues to be an issue. Some industry experts believe that the issue of fair distribution of revenue to the artist may be resolved using blockchain technology, while some are skeptical about the application or the duration of impact. The blockchain may enhance speedier payment using smart contracts, provide additional revenue and promote the music if excellent fan support is achieved. The positive impact on the music industry may only be possible if there are detailed consideration of the industry and careful understanding of the customers.

Modeling of SP responses for geothermal-fluid flow within EGS reservoir (EGS 지열 저류층 유체 유동에 의한 SP 반응 모델링)

  • Song, Seo Young;Kim, Bitnarae;Nam, Myung Jin;Lim, Sung Keun
    • Geophysics and Geophysical Exploration
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    • v.18 no.4
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    • pp.223-231
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    • 2015
  • Self-potential (SP) is sensitive to groundwater flow and there are many causes to generate SP. Among many mechanisms of SP, pore-fluid flow in porous media can generate potential without any external current source, which is referred to as electrokinetic potential or streaming potential. When calculating SP responses on the surface due to geothermal fluid within an engineered geothermal system (EGS) reservoir, SP anomaly is usually considered to be generated by fluid injection or production within the reservoir. However, SP anomaly can also result from geothermal water fluid within EGS reservoirs experiencing temperature changes between injection and production wells. For more precise simulation of SP responses, we developed an algorithm being able to take account of SP anomalies produced by not only water injection and production but also the fluid of geothermal water, based on three-dimensional finite-element-method employing tetrahedron elements; the developed algorithm can simulate electrical potential responses by both point source and volume source. After verifying the developed algorithm, we assumed a simple geothermal reservoir model and analyzed SP responses caused by geothermal water injection and production. We are going to further analyze SP responses for geothermal water in the presence of water production and injection, considering temperature distribution and geothermal water flow in the following research.

Characteristics of coagulants dispersion within In-Line Orifice Mixer (In Line Orifice Mixer에서의 응집제 확산분포 특성)

  • Lim, Kyeong-Ho;Park, Young-Oh;Park, Dae-Jin;Park, No-Suk;Ko, Tae-Kon
    • Journal of Korean Society of Water and Wastewater
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    • v.22 no.6
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    • pp.689-696
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    • 2008
  • In a water treatment process a complete and homogeneous dispersion of the coagulants in the raw water could be most important factor. This research was performed to evaluate coagulation performance of the in-line-orifice mixer which was recently introduced as a rapid mixing device. The test was to determine the actual coagulant dispersion distribution on the overall cross-section at a distance of 1.6~3D from the chemical injection point by measuring zeta potential. From the results of zeta potential test, it was shown that the coagulant dispersion within the in-line orifice mixer was occurred very unevenly. The results have confirmed that it is necessary to increase the velocity of coagulants injection or pressurized water rates, in order to reduce nonuniform distribution of chemicals.

Surface Properties of the Hydrazinolyzed Poly(ethylene terephthalate)/Nylon 6 Fibers

  • Park, Hyeong-Sup;Gi, Moon-Seong;Jeong, Seok-Kyu;Park, Soo-Min
    • Proceedings of the Korean Fiber Society Conference
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    • 1996.04a
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    • pp.158-161
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    • 1996
  • Microfibers of Poly(ethylene terephthalate)(PET)/Nylon 6 (P/N) was heat set at 170C in a fixed state and then treated with hydrazine at 30C for 5, 10, 15, 20, 30 and 40 h. Weight loss from the hydrazine treatment increased according to the hydrazine concentration(Fig.1). In order to investigate in detail the effect of the electrostatic attraction between the dye anion and hydrazide groups in cooperated by hydrazinolysis, -potential of P/N fiber was measured by streaming potential method. The surface charge density, o, of the fiber was evaluated from the -potential.

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