• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.5 no.1
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• pp.9-13
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• 2009

The containment local leakage rate testing in nuclear power plants is performed in accordance with ANSI/ANS-56.8(1994) in Korea. Two methods, the make-up flow rate and the pressure decay, are used for LLRT. Though ANSI/ANS-56.8 does not define clearly the minimum test duration for the make-up flow rate method, it requires obtaining the data after reaching the stable condition. Thus the prerequisite stable condition for data acquisition and the test period for type "C" LLRT is differently applied to each NPPs. Therefore, this study presents a unified test criteria for data stabilization and test duration through experiments to improve the test reliability for type "C".

• Journal of the Korean Society for Nondestructive Testing
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• v.36 no.3
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• pp.231-235
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• 2016

There are two methods for conducting the containment local leakage rate test (LLRT) in nuclear power plants: the make-up flow rate method and the pressure decay method. The make-up flow rate method is applied first in most power plants. In this method, the leakage rate is measured by checking the flow rate of the make-up flow. However, when it is difficult to maintain the test pressure because of excessive leakage, the pressure decay method can be used as a complementary method, as the leakage rates at pressures lower than normal can be measured using this method. We studied the method of measuring over leakage using the pressure decay method for conducting the LLRT for the containment building at a nuclear power plant. We performed experiments under conditions similar to those during an LLRT conducted on-site. We measured the characteristics of the leakage rate under varies pressure decay conditions, and calculated the compensation ratio based on these data.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.4
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• pp.465-474
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• 2010

The effects of four types of tropical protein-rich trees on nutrient digestibility, nitrogen (N) balance, urinary purine derivative (PD) excretion and blood metabolites in four Thai Brahman cattle (290${\pm}$2.5 kg) were studied. The animals were fed twice daily, with each feeding consisting of 1 kg (fresh weight) rice straw and one of the four dietary supplements: i) 1.98 kg oven-dried rain tree pods (RTP) and 20 g premix (RTPP), ii) 980 g RTP and 1 kg sun-dried leucaena leaves and 20 g premix (LLRT), iii) 980 g RTP and 1 kg sun-dried cassia leaves and 20 g premix (CLRT) and iv) 980 g RTP and 1 kg sun-dried mulberry leaves and 20 g premix (MLRT). The apparent dry matter (DM) and organic matter (OM) digestibilities were higher (p<0.05) in cattle fed the CLRT supplement than in those fed the other supplements, whilst the apparent digestibility of neutral detergent fibre (NDF) was higher (p<0.05) in cattle fed the CLRT and MLRT supplements than in those fed the other supplements. The N-balance of cattle fed LLRT and CLRT supplements was higher (p<0.05) than in cattle fed RTPP and MLRT supplements, whilst the apparent digestibility of N was highest (p<0.05) in cattle fed RTPP supplement, compared to the other supplements. Allantoin and PD excretion in the urine, and the ratios of allantoin/DOMI and PD/DOMI were higher (p<0.05) in cattle fed RTPP and MLRT than for those fed LLRT and CLRT supplements. Plasma ${\beta}$-hydroxy butyrate (${\beta}$-HBA) and insulin concentrations were higher (p<0.05) in cattle fed RTPP supplement than in those fed the other supplements. The study demonstrated the value of using local multipurpose trees (MPTs) to improve Brahman cattle feeding systems in the tropics.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.3 s.106
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• pp.272-279
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• 2006

In this paper, we evaluate the performance of frame synchronization words of pilot bit patterns which are used for the channel estimation and frame synchronization confirmation in W-CDMA(Wide band Code Division Multiple Access) system. W-CDMA system also uses compressed mode to make measurements from another frequency without a full dual receiver terminal. It is confirmed by using computer simulation that the proposed frame synchronization words also maintain the frame synchronization property in the compressed mode by using the complementary mapping relationship of preferred pair ROC(Receiver Operating Characteristic) curves with probability of detection and false alarm are used to analized the performance of the proposed frame synchronization words by using the various detection metrics such as LLRT(Log Likelyhood Ratio Test), GLRT(Generalied Likelyhood Ratio Test), soft and hard correlation tests in AWGN and Rayleigh fading channels. It is expected that the research results fer the performance of pilot bit patterns of this paper can be useful reference for the design and implementation of frame synchronization in 3rd generation W-CDMA system.