• 제목/요약/키워드: electric potential

검색결과 1,335건 처리시간 0.032초

뇌서지에 의한 전력통신선로의 전위상승 (A Rise in Electric Potential of Telecommunication Line for Electric Power System by Lightning Surges)

  • 이복희;장석훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 E
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    • pp.1718-1720
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    • 1997
  • This paper deals with n rise in electric potential of telecommunication line for electric power system by lightning surges. When $1.2/50{\mu}s$ and $8/20{\mu}s$ impulse voltage and current were applied on telecommunication cable, the voltage waveforms at the end terminal and equipment were measured. The telecommunication lines, which consist of 60 conductors and 3.5km in length, have some surge protectors such as preposition lightning arrester and TVSS. In each case, the rise in electric potential was measured for differential mode and common mode, respectively. Also, the rise in ground potential and the induced voltages were measured and analyzed. As a result, a significant rise in ground potential was observed for lightning surge. It can cause failure or malfunction of telecommunication systems.

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정상인의 12경맥 측정전위에 대한 유의성 분석(2) -서카디안 리듬, 사상체질분류를 중심으로- (Significance test for electric potential of meridian system(2) -Among circadian rhythms and classification of Sasang constitution-)

  • 남봉현;최환수
    • 한국한의학연구원논문집
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    • 제7권1호
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    • pp.85-103
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    • 2001
  • Objectives : Assuming that the characteristic of meridian system has been similar to this of electric potentials in human body and that measurements of electric potential at well(井穴) and sea(合穴) points in branches of the twelves meridians will be representative of measurements of the twelve meridians, to measure the electric potentials in twenty aged(TAG) and fifty aged(FAG) healthy volunteers groups when they were sleeping or awakening respectively, to do significance test for electric potential of meridian system among circadian rhythms(CR) and Sasang constitutions(SC). Methods : We selected who thirty healthy volunteers were diagnosed by a blood test, urine examination and differentiation of syndromes by five viscera among volunteers. When they were sleeping, their electric potentials of well and sea points in branches of the twelve meridians were simultaneously measured by physiograph. After a minute we measured them again, totally 5 times. And then when they were awakening, their electric potentials were measured 5 times by the above method. Results : Measurements were analyzed by statistical ANOVA test, we obtained that some of the electric potentials of TAG at sleeping significantly varied with CR, SC, and at awakening some of the electric potentials of FAG also significantly did with CR, SC.

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욕조에서의 전위분포 해석을 통한 전격재해 위험성 평가 (Evaluation on Electric Shock Risk due to the Electric Potential Distribution in Bathtub)

  • 김종민;김한상;김성철;김두현
    • 한국안전학회지
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    • 제22권1호
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    • pp.40-46
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    • 2007
  • It is evaluated that electric shock risk in bath so that we made and designed a bathtub which is the same size in real public bath. And then, we did an experiment, provided of electric leakage in various conditions, so we measured how to form an electric potential and knew the electric potential is formed variously under exposed conductor in bath. Also, we made certain that electric shock risk is down if we insert an insulated pipe in bathtub pipe which is prevent from being formed the electric field sharply. The results show that the increased shock risk and safe distance are estimated by the bathtub of limited width and depth, and the voltage simulated on the basis of Flux 3D concept is compared with the measured value.

견비통 환자의 침 치료 전후 12경맥 전위측정 연구(5) (Differences in electric potential of meridian system(5) - Comparing electrical potentials of patients with shoulder lesions -)

  • 남봉현;최환수
    • Journal of Acupuncture Research
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    • 제19권6호
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    • pp.12-23
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    • 2002
  • Objective : Assuming That the Characteristic of Meridian System Has been Similar to This of Electric Potentials in Human Body And that Measurements of Electric Potential at Well(井穴) and Sea(合穴) Points in Branches of the Twelve Meridians(WSBTM) Will Be Representative of Measurements of the Twelve Meridians, to Measure the Electric Potentials of 21 Patients with Shoulder Lesions, And Aching of Shoulder and Arm(肩臂痛)(ASA), to Be Differences in Electric Potentials of Patients Between Before And After Acupuncture Treatment, And Then to Find out the Characteristic of Meridian System in Patients with Shoulder Lesions. Methods : Electric Potentials of Well And Sea Points in the Meridians in Twenty one Patients with ASA Diagnosed by Both x-ray And Self View on Pain at Shoulder And Arm were Repeatedly Measured by Physiograph(PowerLab) at Before And after Acupuncture Treatment, Respectively. Measurements of Those Electrical Potentials Were Analyzed by Factor Analysis. Results : The Electric Potentials of WSBTM At the Left Side Before Acupuncture Treatment Were Divided Into Five Factors, But Those After Acupuncture Treatment Were Done Into Four Factors. On The Other Hand Those At the Right Side Before Acupuncture Treatment Were Divided Into Four Factors, The Number of Factors After Acupuncture Treatment Was Five. Conclusions : In Conclusions, The Number of Factors Before Acupuncture Treatment Are Different from Those After Acupuncture Treatment. In the Results The Effect of Acupuncture Treatment May be Reflected in Measurements of Electric Potential at WSBTM.

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욕조에서의 전위분포 해석 및 전격재해 위험성 평가 (Analysis of the Electric Potential distribution and Evaluation of Electric Shock Risk in Bathtub)

  • 김종민;김한상;정종욱;정진수;김성철
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 춘계학술대회 논문집 전기설비전문위원
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    • pp.37-40
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    • 2006
  • This paper presents the evaluation electric shock risk In bath so that we made and designed a bathtub which is the same size in real public bath. and then we did an experiment, provided of electric leakage in various conditions so, we measured how to form an electric potential and knew the electric potential is formed variously under exposed conductor in bath. also we made certain that electric shock risk is down if we insert an insulated pipe in bathtub pipe which is prevent from being formed the electric field sharply.

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A Comparison of Electrical Stimulation for Electrodic and EDTA-Enhanced Phytoremediation of Lead using Indian Mustard (Brassica juncea)

  • Lim, Jae-Min;Jin, Biao;Butcher, David J.
    • Bulletin of the Korean Chemical Society
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    • 제33권8호
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    • pp.2737-2740
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    • 2012
  • The use of plants to remove toxic metals from soil (phytoremediation) is emerging as a cost-effective alternative to conventional methods for the removal of heavy metals from contaminated soil. Indian mustard (Brassica juncea) was used as the plant to accumulate high tissue concentrations of lead when grown in contaminated soil. For this study, the application of an electric field combined effectively with EDTA-enhanced phytoremediation. A stimulation of direct and alternating electric potential was compared and EDTA-enhanced phytoremediation of lead using Indian mustard has been performed. The effects of experimental parameters such as operating voltage with different concentration of EDTA, the number of graphite electrodes, and cultivation period on the removal of toxic metal were studied. Shoot lead accumulations in Indian mustard increased as the concentration of EDTA and dc electric potential was increased. Two to four folds was increased when EDTA plus a dc electric potential was applied, compared to an ac electric potential. The maximum lead accumulation in the shoots was achieved by applying EDTA plus dc electric potential with 6 graphite electrodes.

Electric double layers interactions under condition of variable dielectric permittivity

  • Payam, Amir Farrokh;Fathipour, Morteza
    • Interaction and multiscale mechanics
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    • 제3권2호
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    • pp.157-171
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    • 2010
  • In this paper, a theoretical method has been developed for the electric double layer interaction under condition of the variable dielectric permittivity of water. Using Poisson-Boltzmann equation (PBE), for one plate and two plates having similar or dissimilar constant charge or constant potential, we have investigated the electric double layer potential, its gradient and the disjoining pressure as well as the effect of variation of dielectric permittivity on these parameters. It has been assumed that plates are separated by a specific distance and contain a liquid solution in between. It is shown that reduction of the dielectric permittivity near the interfaces results in compression of electric double layers and affects the potential and its gradient which leads to a decreased electrostatic repulsion. In addition, it is shown that variation of dielectric permittivity in the case of higher electrolyte concentration, leads to a greater change in potential distribution between two plates.

Coalescence of Two Oppositely Charged Droplets at Constant Electric Potential

  • Lee, Dong Woog;Kang, In Seok
    • Korean Chemical Engineering Research
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    • 제59권2호
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    • pp.247-253
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    • 2021
  • Electrocoalescence is an active technique in petroleum industry, formation of raindrop in cloud, and digital microfluidics. In the present work, electrocoalescence of two droplets under the constant electric potential in air was studied. Through this experiment, we found that the electrocoalescence process could be divided three phases; deformation, formation of liquid bridge, and merging. And the condition for formation of liquid bridge between two droplets was obtained. For the connection of experimental result in constant potential condition with general case in constant charge condition, relationship of charge and potential difference was deduced by numerical computation. In high electric potential case, flat interfaces after recoiling were observed. It was interpreted through a numerical simulation of electric field.

전기비저항탐사에서 음의 겉보기 비저항 (Negative Apparent Resistivity in Resistivity Method)

  • 조인기;김정호;정승환;서정희
    • 지구물리와물리탐사
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    • 제5권3호
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    • pp.199-205
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    • 2002
  • 전기비저항 탐사에서 측정되는 양은 두 전위전극 사이의 전위차이다. 이 전위차가 양일 경우에는 겉보기 비저항도 양의 값을 가지며, 음일 경우에는 겉보기 비저항도 음의 값을 나타낸다. 또한 측정되는 전위차의 부호는 전기장의 방향에 따라 좌우된다. 만약 측정방향과 전기장의 방향이 같다면, 전위차와 겉보기 비저항은 양의 값을 보이게 되며, 그 반대의 경우에는 음의 값을 나타낸다. 일반적으로 지표 전기비저항 탐사에는 측정방향과 1차 전기장의 방향이 같은 전극 배열을 사용하며, 이 방향의 1차 전기장은 2차 전기장에 비하여 항상 크다. 따라서 일반적인 전극배열을 사용하는 지표 전기비저항 탐사의 경우에는 지형이 평탄하고 잡음이 없다면 음의 겉보기 비저항은 나타나지 않는다. 그러나 시추공-시추공 전기비저항 탐사의 경우에는 1차 전기장의 방향과 측정방향이 일치하지 않으며, 경우에 따라서는 1차 전기장의 측정방향 성분이 2차 전기장의 측정방향 성분 보다 그 크기가 작을 수 있다. 이 경우 2차 전기장의 방향과 측정방향이 서로 반대일 경우에는 음의 겉보기 비저항이 나타날 수 있다. 따라서 음의 겉보기 비저항은 측정방향의 1차 전기장이 매우 작은 영역에서 발생할 가능성이 높다.

12 경맥 전위측정 실험에 대한 연구(2) -정상인과 뇌경색환자의 측정전위 비교- (Differences in Electric Potential of Meridian System (2) -Comparing Electrical Potentials between Healthy Volunteers and Patients with Cerebral Infarction-)

  • 남봉현;최환수
    • Journal of Acupuncture Research
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    • 제17권3호
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    • pp.25-35
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    • 2000
  • Objectives : The characteristic of meridian system has been similar to this of electric potentials in human body. Therefore to measure the electric potentials in healthy volunteers and patients, and to find out the characteristic of meridian system and also to do that of differences between them. Methods : Twenty-nine healthy volunteers, thirty patients diagnosed as a cerebral infarction and wind-syndrome caused by hyperactivity of the liver-yang(肝陽化風) were examined into electric potential of well(井穴) and sea(合穴) points in branches of the twelve meridians by physiograph. Results : Measurements were analyzed by factor analysis, then we obtained that both the right and the left electric potential of well and sea points in branches of the twelves meridians in healthy volunteers were divided into two factors, hand meridian and foot meridian. Where as the left electric potential of those in patients with cerebral infarction were divided into three factors, one is foot meridian, another is hand meridian with the exception of large intestine meridian, and the other is large intestine meridian and also the right electric potential were divided into three factors, foot meridian, hand meridian with the exception of large intestine and lung meridian, and large intestine and lung meridian. Conclusions : In the results, healthy volunteers differ from patients in characteristic of electrical potentials, which means that we are able to catch the characteristic of meridian system by electrical potentials of well and sea points.

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