• 조명전기설비학회논문지
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• 제16권4호
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• pp.108-116
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• 2002

본 논문은 인체에 대전된 정전기 방전전압 파형의 측정과 특성 분석에 관한 것으로 정전기 고속과도전압 측정기의 동작원리와 설계기법에 대하에 기술하였다. 여러 가지 실험조건에서 인체에 대전된 전하에 의해 발생한 정전기방전전압의 피크값과 상승시간을 분석하였다. 제안된 전압측정계의 주파수대역은 DC-400[MHz]이다. 각 실험조건에서 정전기 방전전압과 전류의 파형은 거의 비슷하였으며, 크기도 비례적 관계를 나타내었다. 빠른 접근일 때가 느린 접근일 때 보다 빠른 초기상승시간의 정전기방전전압이 나타났다. 인체에 의한 직접 방전전압은 비교적 초기상승시간이 10-30[ns]로 길었으나, 크기는 작았다. 반면에 손에 쥔 금속체를 통한 방전전압은 1~3[ns]의 짧은 상승시간을 가지며 피크값은 매우 크게 나타났다. 결국 정전기 방전전압과 전류 파형은 정전기 방전을 일으키는 접촉물체와 접근속도에 깊은 관계가 있음을 알았으며, 본 연구의 결과는 정전기 장해방지장치의 설계를 위한 기초자료로 활용될 것이다.

• 한국안전학회지
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• 제14권3호
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• pp.69-77
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• 1999

As the use of automatic handling equipment for sensitive semiconductor devices is rapidly increased, manufacturers of electronic components and equipment need to be more alert to the problem of electrostatic discharges(ESD). Semiconductor devices such as IC, LSI, VLSI become a high density pattern of being more fragile by ESD phenomena. One of the most common causes of electrostatic damage is the direct transfer of electrostatic charge from the human body or a charged material to the electrostatic discharge sensitive devices. Accordingly, characteristics of electrostatic attenuation in domestic semiconductor devices is investigated to evaluate the ESD phenomina in the semiconductors in this paper. The required data are obtained by Static Honestmeter. Also The results in this paper can be used for the prevention of semiconductor failure by ESD.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1721-1723
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• 2001

With the rapid development of electronics industry and information-oriented society, the threat of fields radiated from electrostatic discharges (ESDs) to the electronic equipments is becoming more and more dangerous. To apply a proper protection method this paper presents the results of the measurement of the voltage and current peaks and the rise time of ESD derived from a charged human body under a variety of experimental conditions.

• Journal of Microbiology and Biotechnology
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• 제9권5호
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• pp.675-678
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• 1999

Fibrinolytic protease activity was detected in the fruit body of Pleurotus sajor-caju using a fibrin plate method. Two fibrinolytic activities (FPI and Ⅱ) were found at the regions of 14.5 and 86.0 kDa by using gel-filtration column chromatography. FPⅡ was identified as an alkaline protease, whereas FPⅠ was a neutral protease. Both were inhibited by phenanthrolin and EDTA, suggesting that they are metalloprotease. Inactivated enzyme activities were restored by adding Co/sup 2+/ or Zn/sup 2+/. Iodoacetate inhibited FPⅠ, but not FPⅡ. Both enzymes cleaved B/sub β/ and γ chains of the human fibrinogen. FPⅡ showed a preference to hydrophobic and bulky residues of nitroanilidine compounds as substrates, whereas FPⅠ preferred positively charged residues.

• 세라미스트
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• 제22권2호
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• pp.122-132
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• 2019

Wearable electronic devices with batteries must be lightweight, flexible and highly durable. Most importantly, the battery should be able to self-generate to operate the devices without having to be too frequently charged externally. An eco-friendly energy harvesting technology from various sources, such as solar energy, electromagnetic energy and wind energy, has been developed for a self-charging flexible battery. Although the energy harvesting from such sources are often unstable according to the surrounding environment, the energy harvesting from body movements and vibrations has been less affected by the surrounding environment. In this regard, flexible piezoelectric modules are the most attractive solution for this issue, because they convert mechanical energy to electrical energy and harvest energy from the human body motions. Among the various flexible piezoelectric modules, piezoelectric nanofibers have advantages when used as an energy harvester in wearable devices, due to their simple manufacturing process with good applicability to polymers and ceramics. This review focused on diverse flexible piezoelectric nanofibers and discusses their applications as various energy harvesting systems.

• 한국한의학연구원논문집
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• 제13권1호통권19호
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• pp.1-17
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• 2007

Dang jonghae had written five books on chinese medicine, ${\ulcorner}$Hyeoljeungron${\lrcorner}$ is his most important work. He wanted to correct the fallacies of the theory of Jang and Bu by comparing with Oriental and Western medicine. He distinguished Bi from Cheomyuk by comparing the spleen with the pancreas. He recognized Stomach as the warehouse of foods, and explained that Bi took charge of digestion actually. Bi charged the function of Transportation and Blood-govering in addition to plain digestion, he wrote. Dang jonghae regarded the metabolism of the human body as the interaction of Gi, Blood, Water and Fire. And he explained that Bi adjusted them. He classified Syndrome of Blood into five sorts of syndrome and presented four kinds of treatment. Especially he took a serious view of the treatment connected with Bi and Stomach. He set up the theory of Bi and Stomach practically on basis of anatomy, but he didn ' t assorted the physiology and pathology of each organ clearly. However he proved the importance of Bi and Stomach by treating Syndrome of Blood and provided with the foundation of merging chinese and western medicine.

• Journal of Magnetics
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• 제17권1호
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• pp.27-32
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• 2012

Transcranial magnetic stimulation requires an electric field composed of dozens of V/m to achieve stimulation. The stimulation system is composed of a stimulation coil to form the electric field by charging and discharging a capacitor in order to save energy, thus requiring high-pressure kV. In particular, it is charged and discharged in capacitor to discharge through stimulation coil within a short period of time (hundreds of seconds) to generate current of numerous kA. A pulse-type magnetic field is formed, and eddy currents within the human body are triggered to achieve stimulation. Numerous pulse forms must be generated to initiate eddy currents for stimulating nerves. This study achieved high internal pressure, a high number of repetitions, and rapid switching of elements, and it implemented numerous control techniques via introduction of the half-bridge parallel load method. In addition it applied a quick, accurate, high-efficiency charge/discharge method for transcranial magnetic stimulation to substitute an inexpensive, readily available, commercial frequency condenser for a previously used, expensive, high-frequency condenser. Furthermore, the pulse repetition rate was altered to control energy density, and grafts compact, one-chip processor with simulation to stably control circuit motion and conduct research on motion and output characteristics.

• Toxicological Research
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• 제31권2호
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• pp.157-163
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• 2015

Nanotechnology has advanced at an extremely rapid pace over the past several years in numerous fields of research. However, the uptake of nanoparticles (NPs) into the body after administration through various routes may pose a risk to human health. In this study, we investigated the potential ocular toxicity of 20-nm, negatively- charged zinc oxide (ZnO) NPs in rats using micro-computed tomography (micro-CT) and histopathological assessment. Animals were divided into four groups as control group, ZnO NPs treatment group (500 mg/kg/day), control recovery group, and ZnO NPs treatment and recovery group. Ocular samples were prepared from animals treated for 90 days (10 males and 10 females, respectively) and from recovery animals (5 males and 5 females, respectively) sacrificed at 14 days after final treatment and were compared to age-matched control animals. Micro-CT analyses represented the deposition and distribution of foreign materials in the eyes of rats treated with ZnO NPs, whereas control animals showed no such findings. X-ray fluorescence spectrometry and energy dispersive spectrometry showed the intraocular foreign materials as zinc in treated rats, whereas control animals showed no zinc signal. Histopathological examination revealed the retinopathy in the eyes of rats treated with ZnO NPs. Neuronal nuclei expression was decreased in neurons of the ganglion cell layer of animals treated with ZnO NPs compared to the control group. Taken together, treatment with 20-nm, negatively-charged ZnO NPs increased retinopathy, associated with local distribution of them in ocular lesions.

• 한국전통의학지
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• 제15권1호
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• pp.1-48
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• 2006

Dang, jonghae had written five books on chinese medicine, ${\ulcorner}$Hyeoljeungron${\lrcorner}$ is his most important work. He wanted to correct the fallacies of the theory of Jang(臟) and Bu(腑) by comparing with chinese and western medicine. He distinguished Bi(脾) from Cheomyuk(甛肉) by comparing the spleen with the pancreas. He recognized Stomach as the warehouse of foods, and explained that Bi took charge of digestion actually. Bi charged the function of Transportation(運化) and Blood-govering(統血) in addition to plain digestion, he wrote. Dang, jonghae regarded the metabolism of the human body as the interaction of Gi(氣), Blood (血), Water(水) and Fire(火). And he explained that Bi adjusted them. He classified Syndrome of Blood(血證) into five sorts of syndrome and presented four kinds of treatment. Especially he took a serious view of the treatment connected with Bi and Stomach. He set up the theory of Bi and Stomach(脾胃論) practically on basis of anatomy, but he didn't assorted the physiology and pathology of each organ clearly. However he proved the importance of Bi and Stomach by treating Syndrome of Blood and provided with the foundation of merging chinese and western medicine.

• Journal of Pharmaceutical Investigation
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• 제38권1호
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• pp.15-21
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• 2008

Liposomes as one of the efficient drug carriers have some shortcomings such as their short circulation time, fast clearance from human body by reticuloendothelial system (RES) and limited intracellular uptake to target cell. In this study, polyethylenglycol (PEG)-incorporated cationic liposomes were prepared by ionic complexation of positively charged liposomes with carboxylated polyethyleneglycol (mPEG-COOH). The cationic liposomes had approximately $98.6{\pm}1.0nm$ of mean particle diameter and $42.8{\pm}0.8mV$ of zeta potential value. The PEG-incorporated cationic liposomes had $110.1{\pm}1.2nm$ of mean particle diameter with an increase of about 10 nm compared to the cationic liposomes. Zeta potential value of them was $12.9{\pm}0.6mV$ indicating 30mV decrease of cationic charge compared to the cationic liposomes. The amount of PEG which was incorporated onto the cationic liposomes was assayed by using picrate assay method and the incorporation efficiency was $58.4{\pm}1.1%$. Loading efficiency of model drug, doxorubicin, into cationic liposomes or PEG-incorporated cationic liposomes was about $96.0{\pm}0.7%$. Results of intracellular uptake which were evaluated by flow cytometry analysis of doxorubicin loaded liposomes showed that intracellular uptake of PEG-incorporated cationic liposomes was higher than the cationic liposomes or DSPE-mPEG liposomes. In addition, cytotoxicity of PEG-incorporated cationic liposomes was comparable to cationic liposomes. Consequently, the PEG-incorporated cationic liposomes of which surface was incorporated with PEG by ionic complex may be applicable as anticancer drug carriers that can increase therapeutic efficacy.