• 한국환경과학회지
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• 제17권7호
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• pp.817-826
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• 2008

Using high voltage electric fields induced by high voltage AC (10-12 kV/cm, 20 kHz) and pulsed (20-30 kV/cm, 40 Hz) electric field generator as a semipermanent and environment-friendly disinfecting apparatus, the disinfection effect of coliform group in the effluent of sewage plant was investigated. The effects of electric field strength, treatment time, discharge area of a discharge tube, water quality factors (electric conductivity, pH and SS) on its death rate were examined. The death rate of coliform group was increased with increasing electric field strength and treatment time. For AC and pulsed electric field generator, the critical electric field strength was 6 kV/cm and 2 kV/cm, respectively, and the critical treatment time was 5 min and 2 min, respectively, regardless of electric field strength. Comparing the death rate of coliform group by AC and pulsed electric fields used in this study, its death rate was higher for the latter than the former, but did not increase linearly with increasing electric field strength. The results obtained for the effects of discharge area, electric conductivity, pH and SS on the death rate of coliform group using AC electric field (12 kV/cm, 20 kHz) were as follows: its death rate showed the trend to increase linearly with increasing discharge area; for the effect of electric conductivity, its death rate was increased with increasing electric conductivity, regardless of ionic species, increased with increasing cationic valency, but was similar between the same cationic valency; the pH $5{\sim}9$ used in this study did not affect its death rate; its death rate was decreased with increasing SS concentration.

• Journal of Biosystems Engineering
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• 제35권2호
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• pp.100-107
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• 2010

This study was conducted to investigate the effects of electric current stimuli and high-voltage electric field treatments on brown rice germination. The brown rice stimulated by electrical current stimuli, functional electrical stimuli of a pulse type, and high-voltage electric field treatments were observed (Type I, II and III). Treatment Type I was a method of semi-soaking brown rice with electric current stimuli of 0.13 V/cm, 0.19 V/cm, and 0.25 V/cm into Petri-dishes for 72 hours. Type II was a method of semi-soaking brown rice with functional electrical stimuli of a pulse type(DC 1 V, 1 Hz, 5%, and duty cycles of 5%, 20%, and 35%) into Petri-dishes for 72 hours. Type III was a method of water-soaking with high-voltage electric field treatments for 60 hours. High-voltage electric field treatments at 15 kV/cm were also conducted for 2.5 min, 7.5 min, and 10 min, respectively. The germination rate and the sprout growth of brown rice germinated by electric current stimuli with 0.13 V/cm, 0.19 V/cm, and 0.25 V/cm were increased by about 10-15% compared with those of the control group. The germination rate and the sprout growth of brown rice germinated by functional electrical stimuli of pulse type(DC 1 V, 1 Hz, 5% duty cycle) were increased by about 10∼15% compared to those of the control group. Also, the best effective treatment among high-voltage electric field treatments was the 10 min group at 15 kV/cm. The germination rate and the sprout growth of brown rice germinated by this treatment of 10 min at 15 kV/cm were increased by about 10∼20% compared to those of the control group. The treatments of electric current stimuli and high-voltage electric field accelerated the germination rate and sprout growth of brown rice by about 10∼15% compared to those of the control group.

• 한국식품과학회지
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• 제29권6호
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• pp.1175-1183
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• 1997

발효식품의 산패 주원인인 Lactobacillus plantarum을 비열 살균 기술인 고전압 펄스전기장(High Voltage Pulsed Electric Fields, PEF) 처리에 의하여 불활성 시키고자 연속재순환 처리가 가능한 장치를 이용하여 L. plantarum의 불활성에 미치는 전기장 세기, 주파수, 처리시간, 온도 등에 관하여 연구하였다. L. plantarum의 불활성화에 필요한 최소 전기장세기인 임계전기장 세기$(E_c)$는 13.6 kV/cm, 최소처리시간$(T_c)$은 $16.1\;{\mu}s$이었다. 전기장 세기 80 kV/cm에서 생균수의 불활성화율은 주파수 작을수록, 즉 펄스수가 작을수록 증가하여 300 Hz, $2000\;{\mu}s$처리하여 2.5 log의 생균수 감소를 가져왔다. 또한 총처리시간인 재순환 사이클수가 증가할수록 생존율은 감소하였으며, 동일한 사이클수에서는 주파수가 증가할수록 불활성화율이 증가하였다. 즉 동일한 살균시간에서도 펄스전기장에 매우 짧은시간 연속적으로 노출되는 것보다 적절한 시간간격이 필요한 것으로 판단되었다. 처리온도의 경우에는 온도가 증가할수록 L. plantarum의 사멸속도가 증가하여 $50^{\circ}C$에서 80 kV/cm, $1000\;{\mu}s$처리하여 5.6 log의 균체량 감소를 가져왔다.

• 동의생리병리학회지
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• 제16권3호
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• pp.609-615
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• 2002

A medical treatment of alternating current high-voltage electric field therapy is a method in which we get a healing effect, applying electric field to an organism through an artificial device. In order to estimate the clinical effects of alternating current high-voltage electric field load(HEALTHTRON) on the rehabilitation of stroke patients, improvement of a peripheral blood circulation, and psychogenic symptom, we used BEUNZEUNGHEYNG Instrument, NIHSS(the National Institutes of Health Stroke Scale), FIM(Functional Independence Measure)lnstrument to research BEUNZEUNGHEYNG and recovery of rehabilitative funation. and also we used Thermography, Pulse Meter to measure body temperature and pulse, blood elements, and neuro modulators. We have reached the following conclusions after researching the clinical effects of alternating current high-voltage electric field therapy on the recovery of rehabilitative function and peripheral blood circulation. 1. HEALTHTRON efficiently has increased the volume of peripheral blood circulation in stroke patients. 2. HEALTHTRON rapidly has treated the symptoms of sleeplessness, alertness, and dizziness of stroke patients. 3. HEALTHTRON rapidly has improved rehabilitative function of stroke patients and the adjustment to their activities.

• 한국식품과학회지
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• 제45권5호
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• pp.590-597
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• 2013

고전압 펄스 전기장 기술은 가열 공정을 대체할 수 있는 비가열 살균기술로서 꾸준한 연구가 이루어지고 있는 기술이다. 본 실험에서는 미생물의 생리적 측면에서 고전압 펄스 전기장 처리에 의한 효모의 생리적 변화를 살펴보았다. 내염성의 변화를 측정한 결과 사멸하지 않은 세포의 90-99% 이상이 세포 손상에 의해 내염성을 소실하였으며, 내염성을 회복하는데 약 4-6시간의 시간이 걸렸다. 고전압 펄스 전기장 처리 초기에는 세포 내외의 pH 구배(${\Delta}pH$)가 차이가 컸으나 처리시간이 증가함에 따라 그 차이가 감소하였다. 이는 세포의 pH 항상성을 유지시키는 $H^+$-traslocation 기능을 담당하고 있는 $H^+$-ATPase 활성이 소실되었거나 세포막 자체가 손상되어 pH 항상성을 잃어버렸기 때문으로, 이는 고전압 펄스 전기장 처리한 세포의 $H^+$-ATPase의 활성이 초기부터 크게 감소하는 것으로 확인할 수 있었다. 또한 세포의 해당활성이 고전압 펄스 전기장 처리에 의해 크게 감소하여 세포의 대사 기능이 손상되는 것을 확인하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.388-388
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• 2012

In this letter, We have investigated cell characteristics of the alloy FePt-NDs charge trapping memory capacitors with high-k $Al_2O_3$ dielectrics as a blocking oxide. The capacitance versus voltage (C-V) curves obtained from a representative MOS capacitor embedded with FePt-NDs synthesized by the post deposition annealing (PDA) treatment process exhibit the window of flat-band voltage shift, which indicates the presence of charge storages in the FePt-NDs. It is shown that NDs memory with high-k $Al_2O_3$ as a blocking oxide has performance in large memory window and low leakage current when the diameter of ND is below 2 nm. Moreover, high-k $Al_2O_3$ as a blocking oxide increases the electric field across the tunnel oxide, while reducing the electric field across the blocking layer. From this result, this device can achieve lower P/E voltage and lower leakage current. As a result, a FePt-NDs device with high-k $Al_2O_3$ as a blocking oxide obtained a~7V reduction in the programming voltages with 7.8 V memory.

• 한국축산식품학회지
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• 제44권2호
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• pp.239-254
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• 2024

This review sought to categorize studies on meat tenderization and safety through pulsed electric field (PEF) treatment, with a particular focus on reconciling conflicting findings regarding the tenderization effect (i.e., the primary outcome of PEF treatment) and to discuss the underlying mechanisms of these effects. While the tenderization effect may vary depending on the homogeneity of PEF treatment and variations in the conditions of texture measurements, the protein associated with tenderization was degraded by PEF treatment in most studies. PEF technology enables the delivery of a high voltage for a brief duration, typically in the microsecond range, making it a non-thermal technology. One of the distinct advantages of PEF is its ability to preserve the freshness of meat due to its exceptionally short treatment time. While PEF studies have traditionally centered on pasteurizing liquid foods, research on its application to meat is steadily expanding. Therefore, this review aims to elucidate the mechanisms of PEF and provide current insights into the applications of this technology for meat tenderization and microbial inactivation.

• Transactions on Electrical and Electronic Materials
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• 제12권4호
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• pp.148-151
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• 2011

We designed and fabricated aluminium gallium nitride (AlGaN)/GaN high electron mobility transistors (HEMTs) with stable reverse blocking characteristics established by employing a selective fluoride plasma treatment on the drainside gate edge region where the electric field is concentrated. Implanted fluoride ions caused a depolarization in the AlGaN layer and introduced an extra depletion region. The overall contour of the depletion region was expanded along the drift region. The expanded depletion region distributed the field more uniformly and reduced the field intensity peak. Through this field modulation, the leakage current was reduced to 9.3 nA and the breakdown voltage ($V_{BR}$) improved from 900 V to 1,400 V.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권5호
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• pp.319-325
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• 1999

Direct current(d.c.)leakage current voltage characteristics of radio-frequencymagnetron sputtered BaTa\sub 2\O\sub 6\ film capacitors with aluminum(A1) top and indium tin oxide (ITO) bottom electrodes have been investigatedas a function of applied field and temperature. In order to study surfacetreatment effect on the electrical characteristics of as-deposited film weperformed exposure of oxygen plasma on $BaTa_2O_6$ surface. d. c.current-voltage (I-V), bipolar pulse charge-voltage (Q-V), d. c. current-time (I-t) andcapacitance-frequency (C-f) analysis were performed on films. All ofthe films exhibita low leakage current, a high breakdown field strength (3MV/cm-4.5MV/cm), and high dielectric constant (20-30). From the temperature dependence of leakage current,we can conclude that the dominant conduction mechanism is ascribed toSchottky emission at high electric field (>1MV/cm) and hopping conduction at lowelectric field (<1MV/cm). According to our results, the oxide plasma surfacetreatmenton as-deposited $BaTa_2O_6$ resulted in lowering interfacebarrier height and thus, leakage current when a negative voltage applied to the A1 electrode. This can be explained by reduction of surface contamination via etching surface and filling defects such as oxygen vacancies.

• 한국전기전자재료학회논문지
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• 제20권9호
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• pp.793-797
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• 2007

In this paper, the long time breakdown characteristic of the epoxy composite, which is widely used in the insulation system for high voltage application, was estimated with Weibull distribution. In the procedure of the estimation, the short time breakdown characteristics for the epoxy composite specimens, which were made with the variation of hardener and/or filler, were tested firstly. Then the long time voltage-to-time test was implemented. Finally, the long time breakdown voltage of each specimen was estimated with the parameters obtained from the statistical treatment with Weibull distribution. Base on the results, it has been found that the optimal weight ratio of epoxy resin/hardener/filler that has the excellent long time breakdown characteristic was 100/100/65. It was due to the silane treatment which relieves the electric field at the interface between filler and epoxy.