• Nuclear Engineering and Technology
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• 제54권3호
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• pp.781-789
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• 2022

KHNP had licensed Dynamic Control rod Reactivity Measurement (DCRM) method using detector current signals of PWRs in 2006. The method has been applied to all PWRs in Korea for about 15 years successfully. However, the original method was inapplicable to PWRs using low-sensitivity integral fission chamber as ex-core detectors because of their pulse pile-up and the nonlinearity of the mean-square voltage at low power region. Therefore, to overcome this disadvantage, a modified method, DCRM-EK, was developed using kinetics behavior after equilibrium condition where the pulse counts maintain the maximum value before pulse pile-up. Overall measurement, analysis procedure, and related computer codes were changed slightly to reflect the site test condition. The new method was applied to a total of 15 control rods of 1000 MWe and 1400 MWe PWRs in Korea with worths in the range of 200 pcm -1200 pcm. The results show the average difference of -0.4% and the maximum difference of 7.1% compared to the design values. Therefore, the new DCRM-EK will be applied to PWRs using low sensitivity integral fission chambers, and also can replace the original DCRM when the evaluation fails by big noises present in current or voltage signals of uncompensated/compensated ion chambers.

• Journal of Animal Science and Technology
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• 제57권5호
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• pp.17.1-17.6
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• 2015

The present study investigated the nutritional and economic suitability of cashew reject meal (full fat and defatted) as replacement for groundnut cake (GNC) in the diets of laying chickens. A total of eighty four brown shavers at 25 weeks of age were randomly allotted into seven dietary treatments each containing 6 replicates of 2 birds each. The seven diets prepared included diet 1, a control with GNC at $220gkg^{-1}$ as main protein source in the diet. Diets 2, 3 and 4 consist of gradual replacement of GNC with defatted cashew reject meal (DCRM) at 50%, 75% and 100% on weight for weight basis respectively while diets 5, 6 and 7 consist of gradual inclusion of full fat cashew reject meal (FCRM) to replace 25%, 35% and 50% of GNC protein respectively. Each group was allotted a diet in a completely randomized design in a study that lasted eight weeks during which records of the chemical constituent of the test ingredients, performance characteristics, egg quality traits and economic indicators were measured. Results showed that the crude protein were 22.10 and 35.4% for FCRM and DCRM respectively. Gross energy of DCRM was 5035 kcal/kg compared to GNC, 4752 kcal/kg. Result of aflatoxin $B_1$ revealed moderate level between 10 and $17{\mu}g/Kg$ in DCRM and GNC samples respectively. Birds on control gained 10 g, while those on DCRM and FCRM gained about 35 g and 120 g respectively. Feed intake declined (P < 0.05) with increased level of FCRM. Hen day production was highest in birds fed DCRM, followed by control and lowest value (P < 0.05) was recorded for FCRM. No significant change (P > 0.05) was observed for egg weight and shell thickness. Fat deposition and cholesterol content increased (P > 0.05) with increasing level of FCRM. The cost of feed per kilogram decreased gradually with increased inclusion level of CRM. The prediction equation showed the relative worth of DCRM compared to GNC was 92.3% whereas the actual market price of GNC triples that of DCRM. It was recommended that GNC could be completely replaced by DCRM in layer's diets in regions where this by product is abundant. However, FCRM should be cautiously used in diets of laying chickens.

• 조명전기설비학회논문지
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• 제19권8호
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• pp.40-47
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• 2005

본 논문에서는 대표적인 유연송전기기인 UPFC(Unified Power flow Controller)를 대상으로 UPFC 운전이 송전계통에 미치는 영향을 분석하여 송전선 보호를 위한 전류차동방식을 개선하였다. UPFC가 포함된 송전계통을 대상으로 UPFC의 여러 운전 모드에 대한 동적 해석을 통하여 UPFC 동적 특성이 송전선 보호를 위한 전류차동 계전방식에 미치는 영향을 분석하였다. 이를 바탕으로 UPFC가 운전하고 있을 때의 고장을 효과적으로 판단할 수 있도록 개선된 전류차동 보호방법을 제안하였고, 제안된 방법의 타당성을 시뮬레이션으로 입증하였다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2002년도 추계학술발표회요약집
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• pp.74-74
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• 2002

• 대한전기학회논문지:전력기술부문A
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• 제54권12호
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• pp.573-579
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• 2005

Dynamic analysis of a transmission line which is compensated by a FACTS device such as STATCOM, SSSC and UPFC is carried out in this paper and the impacts on conventional line protection methods such as the DCPM (Differential Current Protection Method) and the DPM (Distance Protection Method) are reviewed. A refined DCRM is proposed to detect faults properly regardless of the FACTS operation. The proposed method is applied to a FACTS-compensated line with a variety of faults and is verified by simulation results. An adaptive DPM on a FACTS-compensated line was proposed previously in the literature. In order to emphasize the necessity of the modified DPM, the conventional DPM is applied to a FACTS-compensated system. Significant factors such as fault types, fault locations, and fault resistances as well as FACTS device types are considered for relaying setting.