• Journal of the Korean Society for Nondestructive Testing
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• v.33 no.5
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• pp.465-471
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• 2013

A steam generator in nuclear power plant is a heatexchager which is used to convert water into steam from heat produced in a nuclear reactor core, and the steam produced in steam generator is delivered to the turbine to generate electricity. Because of damage to steam generator tubing may impair its ability to adequately perform required safety functions in terms of both structural integrity and leakage integrity, eddy current testing is periodically performed to evaluate the integrity of tubes in steam generator. This assessment is normally performed during a reactor refueling outage. Currently, the eddy current testing for steam generator of nuclear power plant in Korea is performed in accordance with KEPIC & ASME Code requirements, the eddy current testing system is consists of remote data acquisition unit and data analysis program to evaluate the acquired data. The KEPIC & ASME Code require that the electrical properties of remote data acquisition unit, such as total harmonic distortion, input & output impedance, amplifier linearity & stability, phase linearity, bandwidth & demodulation filter response, analog-to-digital conversion, and channel crosstalk shall be measured in accordance with the KEPIC & ASME Code requirements. In this paper, the measurement requirements of electrical properties for eddy current testing instrument described in KEPIC & ASME Code are presented, and the measurement results of newly developed eddy current testing instrument by KHNP(Korea Hydro & Nuclear Power Co., LTD) are presented.

• Journal of Korean Society of Steel Construction
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• v.27 no.3
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• pp.311-321
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• 2015

In this study, an experimental study to evaluate the seismic performance of beam-to-column connection for medium and low-rise building was conducted. Five connections using SHN490 steel were made with test variables such as flange welded or bolted, web welded or bolted. Specimen SHN-W-W is web welded and flange welded type. Specimen SHN-W-B is web welded and flange bolted type. Specimen SHN-B-W is web bolted and flange welded type. Specimen SHN-B-B is web bolted and flange bolted type. Specimen SHN-EP is a connection with the end plate to the beam ends. Cyclic loadings was applied at the tip of beam following KBC2009 load protocol. The load vs rotation curves for different connection are shown and final failure mode shapes are summarized. The connections are classified in terms of stiffness and strength as semi-rigid or rigid connection. Energy dissipation capacities for seismic performance evaluation were compared.

• Journal of Animal Environmental Science
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• v.15 no.2
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• pp.139-146
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• 2009

This study was carried out to investigate the reproductive and weaned performances in sow farms, which located in Boryeong city, Chungnam. Data surveyed a total of 10,394 litters of sow recorded from April, 2007 to March, 2008 were collected and analyzed. The results obtained were as follows; 1. The average of number of sow and farrowing rate were 314.10 sows and 78.77%, respectively. And then, there was not significant difference among seasons in number of sows, but significant difference among season was found in farrowing rate (p<0.05). 2. The average of litter size at farrowing and at initial sucking were 11.04 and 10.22 pigs, respectively. The significant differences were not all found in litter size among seasons. 3. The number of pigs, age and growth rate at weaning were 9.23 pigs, 25.77 days and 91.48%, respectively. The significant differences among seasons were not found in number of pigs and age at weaning. However, there was significant difference in growth rate at weaning (P<0.05). 4. The average of farrowing rate of sows per year, pigs from sow per year (PSY), and body weight at marketing were 2.25 times, 20.75 pigs, and 110.46 kg, respectively. The significant differences among seasons were not found in farrowing rate per year and weight at marketing, but that was found only in PSY (p<0.05), respectively.

• Reproductive and Developmental Biology
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• v.39 no.1
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• pp.23-28
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• 2015

This study was carried out to investigate the reproductive and growing performances in sow farms located in Chungnam. Data collected from a total of 15 sow farms divided into 3 farm groups for 1 year were analyzed. The results obtained were as follows; The average of sow at small and large farms were 114.25 and 487.88 heads, respectively. And then, the difference among 3 groups in sow farm was not found significantly in farrowing rate. The significant difference among 3 farm groups was significantly found(p<0.05) in total litter size. The litter size born alive at sucking in small sow farm and middle farms were 9.93, and 10.48 pigs. The difference between small and large farms in number of pigs at weaning were significantly shown 8.89, and 9.35 pigs(p<0.05), respectively. The difference among 3 sow farms for ages at weaning showed significantly (p<0.05). The cycles of farrowing rate per year in small, large and middle farms were 2.17, 2.23 and 2.32, respectively. The significant difference among 3 sow groups was found in farrowing rate(p<0.05). The growing rate up to weaning for middle farms was significantly the higher level(94.70%) than that for other farms(p<0.05). The differences among 3 farm groups for marketing weight were not significantly shown.