• Journal of the Korean Vacuum Society
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• v.21 no.4
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• pp.185-192
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• 2012

p-n junction temperature and thermal resistance of Light Emitting Diode (LED) package are affected by the chip size due to the change of the thermal density and the external quantum efficiency considering the heat dissipation through conduction. In this study, forward voltage was measured for two different size LED chips, 24 mil and 40 mil, which consist constitute 16-chip package. p-n junction temperature and thermal resistance were determined by thermal transient analysis, which were discussed in connection with the electrical characteristics of the LED chip and the structure of the LED package.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.30 no.8
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• pp.508-513
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• 2017

Ultraviolet (UV) photodetectors are used in various industries and fields of research, including optical communication, flame sensing, missile plume detection, astronomical studies, biological sensors, and environmental research. However, general UV detectors that employ Schottky junction diodes and p-n junctions have high fabrication cost and low quantum efficiency. In this study, we investigated the characteristics of materials used to manufacture UV photodetectors in a low-cost solution process that requires easy fabrication of flexible substrates. We fabricated p-type NiO and n-type ZnO substrates with wide band gap by the sol-gel method and compared the characteristics of substrates prepared under different spin-coating and heat-treatment conditions.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.142-142
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• 2007

Micro thermoelectric generator has been attractive for the alternative power source to operate the wireless sensor node. In this paper, we designed the column-type micro thermoelectric device and their device characteristics were measured. n-type Bi2Te3 and p-type BiSbTe3 thermoelectric thin films were grown on (001) GaAs substrates by metal organic chemical vapour deposition (MOCVD) and they were pattemed. The height of thermoelectric film were controlled by the deposition time, temperature and MO-x gas pressure. Seebeck coefficient was measured at room temperature and hole concentration and electrical resistivity of thermoelectric film were also characterized.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1993.11a
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• pp.60-63
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• 1993

We have prepared n-CdS/p-InP hetero- junction solar cells by thermal evaporation. The efficiency under the optium conditions without the grid line contact was 7.3%, and the solar cell having glid line contact with SiO AR coating was the open circuit voltage of 0.71V, the short circuit voltage current density of 15mA/cm$^2$, the fill factor of 0.73, and the efficiency of 11.5%. As result of photoresponse in 400-1000nm wavelength the cutoff of n-CdS/p-InP solar at 500nm results from absorption by the CdS \"window\" and the cutoff at 930 nm result from absorption by the InP.

• Journal of the Korean Institute of Telematics and Electronics
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• v.13 no.2
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• pp.23-27
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• 1976

$Si{\cdot}SnO_{2}$ heterojunction was prepared by oxidzing at oxygen atmosphere $SnO_{2-X}$ Which made by Flith evaporation of $SnO_{2}$ powder on III surface of p and n type Si single crystals. The energy band Profile of $Si{\cdot}SnO_{2}$ heterojunction was depicted from its physical properties. This heterojunction was very good rectifying junction, very sensitive in spectral response of Photovoltage at from 400nm to 1200nm, and -10$^{18}$sec of time contant. From above properties, this heterojunction was found ps good high speed photovoltaic device and solar cell.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.94-94
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• 2008

We have performed simulation for Junction Field Effect Transistor(JFET) using Silvco to improve its electrical properties. The device structure and process conditions of Si-control JFET(Si-JFET) were determined to set its cut off voltage and drain current(at Vg=0V) to -0.5V and $300{\mu}A$, respectively. From electrical property obtained at various implantation energy, dose, and drive-in conditions of p-gate doping, we found that the drive in time of p-type gate was the most determinant factor due to severe diffusion. Therefore we newly designed SiGe-JFET, in which SiGe layer is to epitaxial layers placed above and underneath of the Si-channel. The presence of SiGe layer lessen the p-type dopants (Boron) into the n-type Si channel the phenomenon would be able to enhance the structural consistency of p-n-p junction. The influence of SiGe layer will be discussed in conjunction with boron diffusion and corresponding I-V characteristics in comparison with Si-control JFET.

• Journal of Nutrition and Health
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• v.54 no.3
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• pp.321-333
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• 2021

Purpose: Reflux esophagitis is a disease caused by the reflux of stomach contents and stomach acid etc. into the esophagus due to defect in the lower esophageal sphincter and is currently increasing worldwide. This study was conducted to evaluate the effect of a mixture of Citrus Reticulata and Scutellariae Radix (CS) extract on acute reflux esophagitis in rats. Methods: Rats were divided into five groups for examination: normal group (Normal, n = 8), water-treated acute reflux esophagitis rats (Control, n = 8), tocopherol 30 mg/kg body weight-treated acute reflux esophagitis rats (Toco, n = 8), CS 100 mg/kg body weight-treated acute reflux esophagitis rats (CS100, n = 8), CS 200 mg/kg body weight-treated acute reflux esophagitis rats (CS200, n = 8). The experimental groups were administrated of each treatment compounds and after 90 min, acute reflux esophagitis was induced through surgery. Rats were sacrificed 5 h after surgery. We measured the level of reactive oxygen species (ROS) in serum and analyzed the expression of nicotinamide adenine dinucleotide phosphate, inflammatory, and tight junction-related proteins by western blot in the esophageal tissues. Results: CS administration significantly protected the esophageal mucosal damage due to reflux esophagitis, and the level of ROS in the serum was significantly reduced with CS administration as compared to Control. In addition, CS administration significantly suppressed mitogen-activated protein kinase (MAPK or MAP kinase) and nuclear factor-kappa B (NF-κB) pathways and increased protein expressions of tight junction protein. Conclusion: These results suggest that the CS not only regulates the expression of inflammatory proteins by inhibiting oxidative stress, but also reduces damage to the esophageal mucosa by inhibiting the expression of tight junction proteins.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.29A no.2
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• pp.63-67
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• 1992

Shallow $p^{+}-n,n^{+}-p$ diodes have been fabricated using rapid thermal diffusion by solid diffusion source and rapid thermal alloying with pure Aluminum. Diode area and junction depth are designed about 2.83$[\times}10^{-3}cm^{2}$ and 250nm, respectively. Electrical characteristics of $p^{+}-n$ diode show that the ideality factor is 1.04 and reverse current density is 29.3nA/$cm^{2}$, respectively. On the other hand, those of $n^{+}-p$ diode show that the ideality factor is 1.05 and reverse current density is 85.2pA/$cm^{2}$. The reverse currents are measured at 5V reverse bias after rapid thermal alloying for all the measurement.

• The Journal of Internal Korean Medicine
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• v.34 no.4
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• pp.362-374
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• 2013

Objectives : This study was carried out to investigate the inhibitory effect of Banhasasim-tang on early reflux esophagitis by control of gastric peristalsis and the lower esophageal sphincter in mice. Methods : Experimental mice were classified into three groups. The normal group were mice with no inflammation. The control group were mice with gastroesophageal reflux elicited by alcohol. The sample group were mice administered Banhasasim-tang after gastroesophageal reflux elicitation. We observed morphological change and production of ghrelin, substance P, and inducible nitric oxide synthase (iNOS) in gastroesophageal junction mucosa. In addition, we examined change of epithelial junction in esophageal mucosa and change of lower esophageal sphincter distribution. Results : The migration of inflammation-related cells in lamina propria of gastroesophageal junction decreased more in the sample group than in the control group. The positive reaction of ghrelin, substance P, and iNOS significantly decreased more in the sample group than in the control group (p<0.05). Injury of the epithelial junction in the esophageal mucosa and outer oblique layer in the lower esophageal sphincter were significantly mitigated by Banhasasim-tang administration in the sample group (p<0.05). Conclusions : According to the above results, it is supposed that Banhasasim-tang inhibits early reflux esophagitis by controlling not only gastric peristalsis and acid secretion through ghrelin, and substance P but also the lower esophageal sphincter through iNOS.

• Journal of the Korean Vacuum Society
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• v.20 no.4
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• pp.280-287
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• 2011

The heat temperature of a light emitting diode (LED) is investigated with the thermoelectric device (TED). The Peltier effect of the thermoelectric device is used to control the heat radiation and the junction temperature of high-power LEDs. For the typical specific current (350 mA) of high-power (1 W) LEDs, the LED temperature and the p-n junction temperature become $64.5^{\circ}C$ and $79.1^{\circ}C$, respectively. For 0.1~0.2 W driving power of TED, the LED temperature and the junction temperature are reduced to be $54.2^{\circ}C$ and $68.9^{\circ}C$, respectively. As the driving power of the TED increases over 0.2 W, the temperature of LED itself and the junction temperature are increased due to the heat reversed from the heat-sink to LED. As the difference of temperature between LED and the heat-sink is increased, the quantity of reversed heat becomes larger and it results to degrade the cooling capability of TED.