• Journal of the Korean Solar Energy Society
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• v.34 no.1
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• pp.64-71
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• 2014

This study is to perform economic analysis of a PVT-GSHP (Photovoltaic Thermal-Ground Source Heat Pump) system compared to the conventional system which consists of a boiler and a chiller. This research has simulated, developed and analyzed four systems for application in a residential and an office building which was based on the hourly EPI (Energy Performance Index, $kWh/m^2yr$). Case 1 includes a boiler and a chiller to meet heating and cooling demands for a house. Case 2 is the same conventional system as Case 1 for a office. Case 3 is simple summation of Case 1 and 2. And Case 4 is utilizing a PVT-GSHP to meet the combined loads of the house and office. The economic evaluation study was based on IEA ECBCS Annex 54 subtasks C economic assessment methods. This study indicated that PVT-GSHP system can save a building's energy up to 53.9%. Also the SPB (Simple Payback) of the PVT-GSHP system with 0%, 50% initial incentive was 14.5, 6.7 year respectively.

• Proceedings of the KIEE Conference
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• 2005.04a
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• pp.280-282
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• 2005

This paper proposes a simple MPPT control scheme of a Current-Control-Loop Error system Based that can be obtains a lot of advantage to compare with another digital control method, P&O and IncCond algorithm, that is applied mostly a PV system. An existent method is needed an expensive processor such as DSP that calculated to change the measure power of a using current and voltage sensor at the once. Therefore, it is applied a small home power generation system that required many expenses. But, a proposed method is easy to solve the cost reduction and power unbalance problems that it is used by control scheme to limit error of a current control of common sensor. This proposed algorithm had verified through a simulation and an experiment on battery charger using PIC that is the microprocessor of a low price.

• The Transactions of the Korean Institute of Power Electronics
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• v.4 no.6
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• pp.523-530
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• 1999

This paper presents the on -line techniques of SHE-PvVI\I for GTO current source converter. The look-up t table is linearized with this proposed method so that the tum-on/off periods of the GTO switches can be c computed in real-time for any modulation index. This allows the rapid and continuous regulation of the DC O output current while producing the sinusoidal AC input current waveform and unity power factor. The l linearized S}lE-PW~I technique and the high power factor control scheme are Prolxlsed and their‘ performance i is tested analytically. The validity of this proposed technique is well verified through the simulation and e experimental results.

• The Plant Pathology Journal
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• v.37 no.5
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• pp.494-501
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• 2021

Pseudomonas cichorii secretes effectors that suppress defense mechanisms in host plants. However, the function of these effectors, including avirulence protein E1 (AvrE1), in the pathogenicity of P. cichorii, remains unexplored. In this study, to investigate the function of avrE1 in P. cichorii JBC1 (PcJBC1), we created an avrE1-deficient mutant (JBC1^ΔavrE1) using CRISPR/Cas9. The disease severity caused by JBC1^ΔavrE1 in tomato plants significantly decreased by reducing water soaking during early infection stage, as evidenced by the electrolyte leakage in infected leaves. The disease symptoms caused by JBC1^ΔavrE1 in the cabbage midrib were light-brown spots compared to the dark-colored ones caused by PcJBC1, which indicates the role of AvrE1 in cell lysis. The avrE1-deficient mutant failed to elicit cell death in non-host tobacco plants. Disease severity and cell death caused by JBC1^ΔavrE1 in host and non-host plants were restored through heterologous complementation with avrE1 from Pseudomonas syringae pv. tomato DC3000 (PstDC3000). Overall, our results indicate that avrE1 contributes to cell death during early infection, which consequently increases disease development in host plants. The roles of PcJBC1 AvrE1 in host cells remain to be elucidated.

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1726-1746
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• 2022

This paper presents fracture mechanics analysis results for various cracks located at pressurized water reactor pressure vessel nozzle crotch corners taking into consideration constraint effect. Technical documents such as the ASME B&PV Code, Sec.XI were reviewed and then a fracture mechanics analysis procedure was proposed for structural integrity assessment of various nozzle crotch corner cracks under normal operation conditions considering the constraint effect. Linear elastic fracture mechanics analysis was performed by conducting finite element analysis with the proposed analysis procedure. Based on the evaluation results, elastic-plastic fracture mechanics analysis taking into account the constraint effect was performed only for the axial surface crack of the reactor pressure vessel outlet nozzle with cladding. The fracture mechanics analysis result shows that only the axial surface crack in the reactor pressure vessel outlet nozzle has the stress intensity factor exceeding the low bound of upper-shelf fracture toughness irrespectively of considering the constraint effect. It is confirmed that the J-integral for the axial crack of the outlet nozzle does not exceed the ductile crack initiation toughness. Hence, it can be ensured that the structural integrity of all the cracks is maintained during the normal operation.

• Journal of Korea Multimedia Society
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• v.25 no.10
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• pp.1448-1456
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• 2022

This paper studies a model to diagnose efficiency reduction of inverter using Multilayer Perceptron(MLP). In this study, two inverter data which started operation at different day was used. A Multilayer Perceptron model was made to predict photovoltaic power data of the latest inverter. As a result of the model's performance test, the Mean Absolute Percentage Error(MAPE) was 4.1034. The verified model was applied to one-year-old and two-year-old data after old inverter starting operation. The predictive power of one-year-old inverter was larger than the observed power by 724.9243 on average. And two-year-old inverter's predictive value was larger than the observed power by 836.4616 on average. The prediction error of two-year-old inverter rose 111.5572 on a year. This error is 0.4% of the total capacity. It was proved that the error is meaningful difference by t-test. The error is predicted value minus actual value. Which means that PV system actually generated less than prediction. Therefore, increasing error is decreasing conversion efficiency of inverter. Finally, conversion efficiency of the inverter decreased by 0.4% over a year using this model.

• Current Photovoltaic Research
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• v.10 no.3
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• pp.73-76
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• 2022

BIPV (Building Integrated Photovoltaic) supplemented the minimum area problem required when installing existing solar modules. However, in order to apply it to buildings, research was needed to increase the aesthetics of solar modules and use them as a design. Accordingly, modules with color applied to the entire surface of the photovoltaic module were being developed, but there was a disadvantage of low power. Therefore, by dividing and bonding the cell strips, it was possible to improve the output power by applying a shingled technology in which other divided cells overlap in a busbar region where light couldn't be received. Shingled technology was advantageous for color modules because the front busbar part that degrades aesthetics was removed. In this research, four color shingled solar modules (Green, Yellow, Blue, Gray) were manufactured and power degradation was analyzed by measuring transmittance and reflectance. Gray color had 80.83% transmittance, which was 31.31% higher than Yellow, resulting in a power difference of 4.45 W.

• The Korean Journal of Nuclear Medicine
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• v.18 no.1
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• pp.45-53
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• 1984

The purpose of this study is to observe the changes of pulmonary capillary permeability and various hemodynamic parameters before and after Positive End-Expiratory Pressure(PEEP) in Adult Respiratory Distress Syndrome (ARDS). Using a canine oleic acid induced ARDS model, we measured the pulmonary capillary permeability with a slope of lung: heart radioactivity ratio, hemodynamic parameters with Swan-Ganz catheter and blood gas tensions. 1) In normal and ARDS dogs, the PEEP didn't significantly influence the slope of lung: heart radioactivity ratio. But in ARDS group the slope index was increased compaired with that of control group (p<0.05). 2) Also in ARDS group, $PaO_2$ was significantly decreased, and $PaCO_2,\;PvCO_2$, MPAP, $AaDO_2$, Qs/Qt were significantly increased compared with those of control group (p<0.05). 3) In normal dogs, the PEEP didn't influence blood pH or gas tension, $AaDO_2$, Qs/Qt, or hemodynamics. 4) In ARDS dogs, however, the PEEP significantly increased $PaO_2$ and decreased $AaDO_2$, Qs/Qt (p<0.05).

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.73-73
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• 2018

Bacterial leaf blight(BLB), caused by X. oryzae pv. oryzae(Xoo), is one of the most destructive diseases of rice due to its high epidemic potential. Understanding BLB resistance at a genetic level is important to further improve the rice breeding that provides one of the best approaches to control BLB disease. In the present investigation, a collection of 192 accessions was used in the genome-wide association study (GWAS) for BLB resistance loci against four Korean races of Xoo that were represented by the prevailing BLB isolates under Xoo differential system. A total of 192 accessions of rice germplasm were selected on the basis of the bioassay using four isolated races of Xoo such as K1, K2, K3 and K3a. The selected accessions was used to prepare 384-plex genotyping by sequencing (GBS) libraries and Illumina HiSeq 2000 paired- end read was used for GBS sequencing. GWAS was conducted using T ASSEL 5.0. The T ASSEL program uses a mixed linear model (MLM). T he results of the bioassay using a selected set of 192 accessions showed that a large number of accessions (93.75%) were resistant to K1 race, while the least number of accessions (34.37%) resisted K3a race. For races K2 and K3, the resistant germplasm proportion remained between 66.67 to 70.83%. T he genotypic data produced SNP matrix for a total of 293,379 SNPs. After imputation the missing data was removed, which exhibited 34,724 SNPs for association analysis. GWAS results showed strong signals of association at a threshold of [-log10(P-value)] more than5 (K1 and K2) and more than4 (K3 and K3a) for nine of the 39 SNPs, which are plausible candidate loci of resistance genes. T hese SNP loci were positioned on rice chromosome 2, 9, and 11 for K1 and K2 races, whereas on chromosome 4, 6, 11, and 12 for K3 and K3a races. The significant loci detected have also been illustrated, NBS-LRR type disease resistance protein, SNARE domain containing protein, Histone deacetylase 19, NADP-dependent oxidoreductase, and other expressed and unknown proteins. Our results provide a better understanding of the distribution of genetic variation of BLB resistance to Korean pathogen races and breeding of resistant rice.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.609-621
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• 1997

The purpose of this study was to evaluate the shear bond strength of three light-cured glass ionomer cements to blood contaminated bovine dentin. The materials used in this study were Fuji II LC, Dyract and Variglass VLC. The dentin conditioners were 10% polyacrylic acid, 10% maleic acid and 10% phosphoric acid. 180 lower anterior bovine teeth were selected in this study. The teeth were embedded in acrylic resin and were grounded with 320 to 600 grit silicon carbide paper to create a flat dentin surface. The teeth were divided into SIX groups. The experimental procedures in six groups were as follows; Group l(GF) : Samples bonded to dentin surface with Fuji II LC after 10% polyacrylic acid treatment. Group 2(BGF) : Samples bonded to dentin surface with Fuji II LC after 10% polyacrylic acid treatment and blood contamination. Group 3(MD) : Samples bonded to dentin surface with Dyract after 10% maleic acid treatment. Group 4(BMD) : Samples bonded to dentin surface with Dyract after 10% maleic acid treatment and blood contamination. Group 5(PV) : Samples bonded to dentin surface with Variglass VLC after 10% phosphoric acid treatment. Group 6(BPV) : Samples bonded-to dentin surface with Variglass VLC after 10% phosphoric acid treatment and blood contamination. Group 1,3 and 5 were classified into the control groups, while group 2,4 and 6 were classified into the experimental groups. Each group contained 30 samples. After 24 hours water storage at $37^{\circ}C$, all smples were subjected to a shear load to fracture at a cross head speed of 1.0 mm/min with Instron universal testing machine(No. 4467). Debonded surfaces were observed under Scanning Electron Microscope(Hitachi S-2300) at 20kvp. The data were evaluated statistically at the 95% confidence level with Student's t-test. The following results obtained; 1. Shear bond strengths were higher in the control groups(1,3,5 group) than in the experimental groups(2,4,6 group). 2. The shear bond strength of group 5(PV) was the highest in the control groups, and the group 5 was significantly higher than the group l(GF) on the shear bond strength. 3. The group 4(BMD) was the highest on the shear bond strength, and the group 2(BGF) was the lowest in the experimental groups. The group 4(BMD) and 6(BPV) showed a significant difference with the group 2 on the shear bond strength. 4. All the groups showed an adhesive-cohesive failure. except the group 2(BGF) showing adhesive failure.