• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.423-426
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• 2009

POSTECH Graduate School of Wind Energy is trying to upgrade the PMSG used for Unison U50 to 900 kW class. Intensive optimization efforts are carried out the reduce the axial size and total weight of the generator while increasing the rated output to 900 kW. The generator features 3.32m stator inner radius, 671mm stator length, 84 pole, 25 rated rpm and 31.6kN/$m^2$ shear force density. To reduce the gross weight, the stronger magnetic material is applied with optimal magnet size resulting lowest cogging torque. Also, instead of stator skewing the stator, the magnet position along the circumference is optimized to further reduce the cogging torque. This scheme eliminates the stator skewing procedure and may enhance the productivity. This method also reduces the total harmonic distortion. In this report, upgrade method, no-load line to line voltage and phase voltage, cogging torque, loss calculations and thermal analysis are presented.

• Solar Energy
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• v.18 no.3
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• pp.147-151
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• 1998

Several PV-diesel hybrid systems were built in isolated islands in Korea, where they are far from the inland to be supplied the electric power to a utility level from it. A lot of efforts has been concentrated to find a cost-effective electric supply system with higher reliability and minimum maintenance when compared with a diesel generator. For this purpose, an autonomous PV-diesel hybrid system with multi-channel remote monitoring system was investigated to supply electric power under minimum operating cost and maintenance in a small isolated island. In this report, the economic analysis was performed for comparison with photovoltaic system and diesel generator by computer simulation. And it was proven that a PV system is more cost-effective than an internal combustion engine for the remote island with less than 150 households. Especially, in the case of islands with less than 50 households, the initial construction cost of the PV system is comparable to and its operating cost is about 70% less than the diesel generator.

• Proceedings of the KIEE Conference
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• 1999.11c
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• pp.582-584
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• 1999

Generator has synchronized with power Network after build-up output voltage. In order to prevent a current surge when synchronizing, the conditions such as identical no-load voltages identical no-load frequencies and identical phase positions must be met between generator voltage and network voltage. Hydro-Pump generators or Gas-turbine generators, Co-generation Generators that serve peak load of network are synchronized many times. So, Automatic Synchronizing Circuits are very important service. This report apply Diagnosis methods the Automatic Synchronizing Circuits(Device) by developing simulator.

• Journal of environmental and Sanitary engineering
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• v.15 no.2
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• pp.27-32
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• 2000

The hydrolysis of pesticides by ozone was studied using the ozone generator manufactured for home appliance. Ozone was treated to remove the residual pesticides in the vegetables such as lettuce, cabbage, spinach and Japanses parsely. The experimental results were optimistic with removal efficiency of more than 50%, but its achievement depends on the operational hours of zone generator and chemical structures of pesticides. This report was determined as an optimal conditions for the removal rate of pesticides as follows: ozone input concentration in the contactor was $2mg/{\ell}$, ozone contact time was at least 30 min without washing vegetables, but it was OK at 10 min in case that number of washing increases.

• Genomics & Informatics
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• v.9 no.4
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• pp.189-193
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• 2011

Simple sequence repeats (SSRs) are ubiquitous short tandem duplications found within eukaryotic genomes. Their length variability and abundance throughout the genome has led them to be widely used as molecular markers for crop-breeding programs, facilitating the use of marker-assisted selection as well as estimation of genetic population structure. Here, we report a software application, "SSR-Primer Generator " for SSR discovery, SSR-primer design, and homology-based search of in silico amplicons from a DNA sequence dataset. On submission of multiple FASTA-format DNA sequences, those analyses are batch processed in a Java runtime environment (JRE) platform, in a pipeline, and the resulting data are visualized in HTML tabular format. This application will be a useful tool for reducing the time and costs associated with the development and application of SSR markers.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.388-391
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• 2002

We report our CAB system on thermal analysis for mould designer who is not expert of numerical simulation. Our mathematical model of thermal analysis is axi-symmetrically. It has an automatic mesh-generator that is based on Delaunay method, by using CAD data. And boundary conditions are also fitted automatically.

• Korean Management Science Review
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• v.1
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• pp.81-87
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• 1984

이 글에서는 PDS/MAGEN이란 무엇이며 그 사용방법은 어떻게 하고 어떤 면에서 장점을 가지고 있는가를 살펴보았다. PDS/MAGEN도 컴퓨터의 다른 소프트웨어와 마찬가지로 사용법을 새로 알아야 하지만 APEX 등 선형계획 문제를 위한 소프트웨어를 사용할 때 매우 편리하다. 일단 문제가 구성되면 선형계획법이나 PDS/MAGEN의 전문가가 아니더라도 선형계획법을 쉽게 사용할 수 있으므로 실제 업무에서는 매우 필요한 소프트웨어라 하겠다. PDS/MAGEN은 현재 KAIST부설 전산개발센타내 CDC Cyber 174에 장착되어 있어, 기타 다른 기종에 적합한 소프트웨어들도 보급 판매되고 있으며, 이의 도입 적용은 효율적인 선형계획기법 응용의 필요불가결한 소프트웨어라 하겠다.

• Journal of the Korean Society of Radiology
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• v.15 no.5
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• pp.755-760
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• 2021

In this study, the shielding rate of major X-ray protective equipment used in the medical environment was calculated using X-ray spectrum data emitted from the diagnostic X-ray generator of The Institute of Physics and Engineering(IPEM) Report-78, and the applicability of radiation protection was investigated. Radiation shielding rates were calculated through reduction rates of air-kerma and total intensity for lead apron (0.3 mmPb), thyroid shield (0.5 mmPb), lead goggles (0.5 mmPb), and lead glass (1.8, 2.7, 3.3 mmPb) used for diagnostic X-ray protection. As a result, the shielding rate calculated as the air kerma reduction rate ranged from 96.31 to 100% at 80 kV, and 90.35 to 100% at 120 kV. In addition, the results of this calculation were well matched with the results of previous studies measuring the actual shielding rate, and it is expected that the X-ray spectrum data of IPEM Report-78 can be used for radiation protection.

• Journal of Chest Surgery
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• v.32 no.7
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• pp.668-670
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• 1999

The most important indication for the removal of the lead-electrode system is the presence of an infection. When an infection occurs, the entire pacemaker system including the impluse generator and lead-electrode system should be removed. The entrapped electrode can be removed by a continous traction, by the use of forceps, snares or baskets, by the use of a locking stylet or a dilator sheath, and by an operation. We report a case that underwent a removal of an entrapped transvenous pacemaker electrode by the use of snaring technique.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.2
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• pp.184-190
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• 2008

Various ECT techniques have been applied basically to assess the integrity of steam generator tithing in nuclear power plant. Among these techniques, the bobbin probe technique is applied generally to examine the volumetric flaws such as a crack-like defect and wear which is generally occurred on steam generator tubing, and additionally MRPC probe is used to examine closely tile top of tubesheet and bending regions due to the high possibility of cracking. Dent and bulge also may be formed on tube during installation process and operation of steam generator, but the dent and bulge indications greater than specific size criteria are recorded on examination report because these indications are not considered as flaw. These indications can be easily detected with bobbin probe and approximately sized with profile bobbin probe, but the size and shape can not be accurately verified. Accordingly, in this study, the $8{\times}1$ multi-array EC probe was designed to increase the measurement accuracy of the sectional profiling EC testing of tube. As a result, we would like to propose the application of $8{\times}1$ multi-array EC probe for the measurement of size and shape of profile change on steam generator tube in OPR-1000 nuclear power plant.