• Journal of the Korea Concrete Institute
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• v.15 no.5
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• pp.739-746
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• 2003

Various researches on the application of polymer dispersions to the cement mortar and concrete have been carried out in many countries like America, Japan and Germany and so on due to their high performance and good modification effect. PAE of polymer dispersion widely used in situ was employed that the high flowability may be induced in the cement mortar. In order to investigate the modification of cement mortar with high flowability by PAE and fracture mode of adhesive strength properties in tension of that, experimental parameters were set as PAE solid-cement ratio(P/C) and cement: fine aggregate(C:F) and the experiments such as unit weight, flow, consistency change, crack resistance and segregation that inform on the general properties have been done. Adhesion in tension is measured with a view to comprehending the properties and fracture mode in tensile load. Consistency change of cement mortar modified by PAE did grow better as the ratio of PAE solid-cement increased and was much superior to that of resin based flooring such as polyurethane and epoxy which recorded the loss of consistency in 90 min. after mixing. Adhesive strength in tension increased with continuity during curing period and showed the maximum in case of C:F=1:1 and P/C=20%.

• Nutrition Research and Practice
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• v.8 no.5
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• pp.494-500
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• 2014

BACKGROUND/OBJECTIVES: This study investigated whether Padina arborescens extract (PAE) protects INS-1 pancreatic ${\beta}$ cells against glucotoxicity-induced apoptosis. MATERIALS/METHODS: Assays, including cell viability, lipid peroxidation, generation of intracellular ROS, NO production, antioxidant enzyme activity and insulin secretion, were conducted. The expressions of Bax, Bcl-2, and caspase-3 proteins in INS-1 cells were evaluated by western blot analysis, and apoptosis/necrosis induced by high glucose was determined by analysis of FITC-Annexin V/PI staining. RESULTS: Treatment with high concentrations of glucose induced INS-1 cell death, but PAE at concentrations of 25, 50 or $100{\mu}g/ml$ significantly increased cell viability. The treatment with PAE dose dependently reduced the lipid peroxidation and increased the activities of antioxidant enzymes reduced by 30 mM glucose, while intracellular ROS levels increased under conditions of 30 mM glucose. PAE treatment improved the secretory responsiveness following stimulation with glucose. The results also demonstrated that glucotoxicity-induced apoptosis is associated with modulation of the Bax/Bcl-2 ratio. When INS-1 cells were stained with Annexin V/PI, we found that PAE reduced apoptosis by glucotoxicity. CONCLUSIONS: In conclusion, the present study indicates that PAE protects against high glucose-induced apoptosis in pancreatic ${\beta}$ cells by reducing oxidative stress.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.2 s.332
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• pp.81-86
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• 2005

In this paper, the high linear Doherty amplifier has been realized by employing the PBG(Photonic Band Gap) structure. The PBG structure has been employed on the output matching network of the power amplifier. The proposed Doherty amplifier has been improved in PAE and IMD. The PAE has been $36.4\%$ and the IMD has been -24.5 dBc, respectively.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.326-329
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• 2003

In this paper, we designed and implemented a high power amplifier(HPA) to achieve the high Power Added Efficiency(PAE) over 40% at the 90W output power for the ISM-band(fo=2.45GHz). HPA presented in this paper has 3-stage drive amplifier and 1-stage final amplifier. In the final amplifier, we utilized balanced amplifier configuration with GaAs FET and each of two amplifiers has the push-pull configuration to increase PAE. From the measurement results, we obtained PAE of 42.95% at the 90.57W output power.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.1
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• pp.52-56
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• 2014

In this paper, a high-efficiency power amplifier is implemented using a gate and drain bias control circuit for WPT (Wireless Power Transmission). This control circuit has been employed to improve the PAE (Power Added Efficiency). The gate and drain bias control circuits consists of a directional coupler, power detector, and operation amplifier. A high gain two-stage amplifier using a drive amplifier is used for the low input stage of the power amplifier. The proposed power amplifier that uses a gate and drain bias control circuit can have high efficiency at a low and high power level. The PAE has been improved up to 80.5%.

• Journal of radiological science and technology
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• v.16 no.2
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• pp.45-50
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• 1993

In this paper, the PAE of tube voltage of 93 diagnostic X-ray units those are using at the 19 general hospitals and 9 local clinics in the area of Sungnam, Inchun, and Seoul have been surveyed. The results are summarized as following. 1. PAE of tube Voltage 70, 100KV at the 56 (60%) X-ray units were ${\pm}7%$ below, at the 8 units (9%), were ${\pm}7%$ above, and those 29 X-ray units (31%) were ${\pm}7%$ below or above with the 70, 100KV tube Voltage in a unit. 2. PAE ${\pm}7%$ below were 68 X-ray units, at the low tube voltage (70KV), and 76 X-ray units at the high tube Voltage (100KV). 3. For six year-use abofe, used X-ray units were PAE ${\pm}7%$ above, and so, the longer used years the more X-ray units became declined in those performance. 4. PAE of tube Voltage were better efficiency at the large capacity 30 X-ray units than small capacity 10. 5. PAE ${\pm}7%$ abovein were only 8 units among 84 diagnostic X-ray units in the general hospitals.

• Natural Product Sciences
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• v.27 no.3
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• pp.208-215
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• 2021

𝛽-Patchoulene (𝛽-PAE) is a tricyclic sesquiterpene which performed many potential bioactivities and can be found in patchouli oil but in very low concentration. This study aimed to obtained 𝛽-PAE in high concentration by conversion of patchouli alcohol (PA) in patchouli oil under acid catalyzed reaction. Patchouli oil was fractinated by vacuum distillation at 96 kPa to get the fraction with the highest PA content. H₂SO₄ and ZnCl₂ were used respectively as homogeneous and heterogeneous acid catalysts in the conversion reaction of the selected fraction. Patchouli oil, the fractions and the products were analysed by using GC-MS and FTIR instruments. Moreover, the interaction of 𝛽-PAE to COX-2 protein was studied to understand the antiinflammation activity of 𝛽-PAE. The results showed that patchouli oil contains 25.3% of PA. The selected fraction which has the highest PA content (70.3%) was distilled at 151 - 152 ℃. The application of ZnCl₂ catalyst in conversion reaction did not succeed. In contrast, H₂SO₄ as a catalyst in acetic acid solvent succeeded in converting the overall fraction of PA to 𝛽-PAE. Furthermore, the molecular docking study of 𝛽-PAE against COX-2 enzyme showed van der Waals and alkyl-alkyl stacking interactions on ten amino acid residues.

• Journal of Advanced Navigation Technology
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• v.9 no.2
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• pp.164-169
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• 2005

In this paper, the high efficiency Doherty power amplifier using adaptive bias technique has been designed and realized for 2.3GHz Wibro applications. The RF performances of the Doherty power amplifier using adaptive bias technique have been compared with those of a class AB amplifier alone, and conventional Doherty amplifier. The Maximum PAE of designed Doherty power amplifier with adaptive bias technique has been 36.6% at 34.0dBm output power. The proposed Doherty power amplifier showed an improvement 1dB at output power and 7.6% PAE than a class AB amplifier alone.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.2
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• pp.80-85
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• 2010

In this paper, the efficiency of power amplifier has been maximized by the application of EER structure, and the linearity has been improved by using metamaterial structure. This paper has proposed a design of power amplifier in class-F to get the PAE, and to control dynamic power using envelope detector. CRLH structure gets high-linearity by removing harmonics arisen from the mismatching of matching circuit. The PAE and the 3rd order IMD have been improved 5.93 %, 12.83 dB compared with those of conventional Class-F amplifier, respectively.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.8 s.111
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• pp.707-712
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• 2006

In this paper, dual bias control circuit and PBG(Photonic BandGap) structure have been employed to improve PAE(Power Added Effciency) of the Doherty amplifier on Input power level. The gate and drain bias voltage has been controlled with the envelope of the input RF signal and PBG structure has been employed on the output port of Doherty amplifier. The proposed Doherty amplifier using dual bias controlled circuit and PBG has been improved the average PAE by 8%, $IMD_3$ by -5 dBc. And proposed Doherty amplifier has a high efficiency more than 30% on overall input power level, respectively.