• Transactions on Electrical and Electronic Materials
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• 제7권5호
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• pp.262-266
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• 2006

The insulation diagnostic test and the AC breakdown test were performed under off-line using the 3.3 kV class induction motor which have been served for 10 years. These tests were conducted in means of nondestructive and destructive test. In this paper, we compared the correlation between the nondestructive and destructive test. Furthermore we setup an experimental condition with moisture and compared the insulation characteristics between moist and dry sample. From the results of the nondestructive and destructive test, it was found that the second AC current, which is the previous step of insulation breakdown, suddenly increased at a point of around 8.5 kV. The insulation breakdown of moist sample occurred at 12-14 kV, which is 4-5 kV lower than dry sample.

• Computers and Concrete
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• 제21권5호
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• pp.485-493
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• 2018

Statistical analysis has found useful application in the design of experiments (DOE) especially optimization of concrete ingredients however, to be able to apply the concept properly using computer aided applications there has to be an upper and lower limits of responses fed to the system. In this study, the production of high-performance steel fiber concrete (HPSFC) at five different fiber addition levels by volume with two aspect ratios of 60 and 83 were studied under two curing methods completely dry cured (DC) and moist cured (MC) conditions. In other words, this study was carried out for those limits based on material properties available in North Cyprus. Specimens utilized were cubes 100 mm size casted and cured for 28 days and tested for compressive strength. Minitab 18 statistical software was utilized for the analysis of results at a 5 per cent level of significance. Experimentally, it was observed that, there was fluctuation in compressive strength results for the two aspect ratios and curing regimes. On the other hand P-value hypothesis evaluation of the response showed that at the stated level of significance, there was a statistically significant difference between dry and moist curing conditions. Upper and lower limit values were proposed for the response to be utilized in DOE for future studies based on these material properties. It was also suggested that for a narrow confidence interval and accuracy of the system, future study should increase the sample size.

• 수산경영론집
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• 제40권3호
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• pp.189-205
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• 2009

This study is aimed to analyze the economic feasibility comparison of the extruded pellets and moist pellets on the Oliver flounder culture farms in Jeju Island. In order to do this, we selected 2 farms (M and S farms) in Jeju Island as a sample. In the study, various analyses including productivity analysis, cost structure analysis, profitability and economic feasibility analysis by feed type were conducted for two sample farms of Oliver flounder culture. The results of economic analysis by feed type on the Oliver flounder culture can be summarized as follows; First, there were not significant differences in productivity by feed type. Second, results of the profitability analysis on farm M by feed type showed the profitability was estimated to be 15.52% and 9.83% in EP and MP, respectively. In addition, the profitability of farm S was estimated to be 28.37% and 33.72% in EP and MP, respectively. Third, results of the economic analysis on farm M by feed type indicated that an internal rate of return(IRR) was 8% and 7% and a benefit-cost ratio was shown to be 1.64 and 1.11 in EP and MP, respectively. Furthermore, the economic analysis of farm M by feed type showed that an IRR was 19% and 24% and a benefit-cost ratio was calculated to be 1.4 and 1.51 in EP and MP, respectively. In summary, it is especially emphasized that economic valuation is not related to feed types (EP and MP). Finally, in order to improve the economic feasibility, it should be more focused on the efficient business management of the Oliver flounder aquaculture.

• 펄프종이기술
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• 제45권5호
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• pp.49-55
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• 2013

To explore the paper materials for restoration of the Annals of the Joseon Dyansty, durability of the three type of the traditional Korean Papers were estimated in this study, through moist heat artificial aging test. Three types(D, F, and G) which showed the best preservation performance in dry heat and UV treatment in the previous study were selected and artificial accelerated aging treatment with moist-heat process was conducted; the viscosity change rate was D>G>F; folding endurance G>D>F; $L^*$ value F>D>G; $a^*$ and $b^*$ change rate D>G>F; brightness decrease rate D>G>F, suggesting paper F showed the least change rate in physical/optical properties. Also the CLSM image observation showed fair coherence among fibers and confirmed paper mulberry. And in FDI extraction from each sample, paper F showed the highest value. Overall, paper F (traditional glossy paper) showed the highest stability against thermal treatment. It confirms that paper F is suitable as restoration paper for tributary remains including the annals of the Joseon Dynasty for its steady strength/viscosity decrease rate and color change rate.

• 한국지반환경공학회 논문집
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• 제15권5호
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• pp.57-65
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• 2014

경제적, 기술적인 이유에서 실내시험을 위한 in situ 상태 그대로의 현장 모래 시료를 채취하는 것은 매우 어렵다. 따라서 현장과 유사한 상태의 시료 조성을 위한 다양한 시료 재성형 방법이 제시되었으며, 연구 목적에 따라 적합하다고 판단되는 시료성형방법이 다양하게 적용되고 있다. 본 논문에서는 모래의 시료 재성형 시 널리 이용되고 있는 습윤다짐법, 건조낙사법, 그리고 건조퇴적법을 적용하여 동일한 상대밀도로 시료를 조성한 후, 일정한 구속압 조건에서 압밀배수전단 시험을 수행하였다. 또한 자체제작을 통해 시료의 상 하부 캡에 압전소자를 설치하여 압밀 종료 시점과 전단과정에서의 탄성파 속도를 측정함으로써 시료 재성형 방법 및 상대밀도에 따른 오타와 모래에서의 거동 특성 및 전단거동 시의 탄성파 속도의 변화 경향을 분석하였다. 분석 결과, 시료 조성방법에 따라 전단과정에서 모래의 거동에는 차이가 발생할 수 있는 것으로 나타났으며, 전단과정 시 전단파 속도는 체적 변화양상과 동일한 경향을 보이는 것으로 나타났다.

• 수산해양교육연구
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• 제25권3호
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• pp.553-563
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• 2013

This study was conducted to evaluate the quality characteristics (proximate composition, fatty acids, amino acids and sensory properties) of whole body and dorsal muscle in olive flounder, which is switch size from juvenile to growing fed extruded pellets (EP) and raw fish-based moist pellet (MP) for 9 months. Sample was collected at 5 and 9 months to compare with those of EP and MP. Whole body crude protein of fish fed EP at 9 months was significantly higher than that of fish fed MP (P<0.05). Linolenic acid(18:3) and n-6/n-3 ratio in dorsal muscle of fish fed EP were significantly higher than those of fish fed MP (P<0.05). No significant differences were observed in the results of the flavor, color, taste and texture of the muscle of the fish fed EP compared to those fed MP (P>0.05). Based on the experimental results, we concluded that olive flounder cultured with EP is not inferior to those fed MP for quality characteristics of whole body and muscle.

• 한국식생활문화학회지
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• 제18권1호
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• pp.37-44
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• 2003

Fat and sugar reduced yellow layer cake system was developed with varied replacement level of 30%, 60%, and 90% for AD(amylodextrin) and 10%, 30%, and 50% for PD(polydextrose). Physicochemical and sensory characteristics were investigated and optimum replacement level was also decided using response surface methodology. Sample groups of PD10AD30 had significantly the lowest specific gravity and viscosity, indicating the stable batter system with high air incorporation. Sample groups with PD10AD90 showed the highest volume index and were not significantly different from those of the PD10AD30. Sensory results indicated that PD30AD30 were significantly the most springy and moist, and the least hard of all sample groups. Sample groups with PD10AD90 had the least adhesiveness value. To establish the optimum substitution level using RSM, the restriction level was set up as moistness over five point, hardness under five points, and adhesiveness under four points. The optimum substitution level was 20% for PD and 88% for AD.

• 한국산림과학회지
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• 제95권4호
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• pp.443-452
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• 2006

다릅나무 임분의 입지 환경과 해발고에 따른 생장량을 비교하기 위해 강원도 평창군 중왕산에서 $30m{\times}30m$ 크기의 조사구 28곳을 선정해서 식생 및 입지 환경 특성을 조사했다. 또한 해발고가 약 100 m 간격으로 있는 5곳의 조사구에서 각 2그루씩 다릅나무를 선발해서 수간석해했다. 다릅나무는 주로 해발 790~1,170 m 사이의 북향의 능선 또는 사면에서 출현했다. 다릅나무의 입지는 A층 깊이가 평균 21.2 cm로 깊고, A층 수분 함량은 35.6%로 높은 편이며, 토양 비옥도가 낮은 지역이었다. 다릅나무와 함께 중요치가 높은 수종은 신감나무, 물푸레나무, 당단풍나무, 고로쇠나무, 느릅나무, 피나무, 사사나무 등이었다. 중왕산 지역의 다릅나무림은 TWINSPAN에 의해 다릅나무-사시나무 군락, 다릅나무-느릅나무 군락(이상 건조형), 다릅나무-피나무 군락, 다릅나무-쪽동백나무 군락(이상 습윤형)으로 나누어졌다. 군락유형별 ha당 개체수는 습윤형 군락이 건조형 군락보다 많았다. 한편, 다릅나무의 연간 수고 생장량은 10년까지 급격한 증가를 보이다가 점차 감소했으며, 초기 수고 생장이 빨라 초기 침입수종의 생장전략을 보여줬다. 또한 다릅나무는 수령 40년 이상에서도 주변목의 고사로 경쟁이 완화되면 재적 생장량이 크게 증가하는 특성을 보였으며, 수령 50년 이후 경제성 있게 수확할 수 있는 것으로 판단됐다.

• Restorative Dentistry and Endodontics
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• 제38권4호
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• pp.234-240
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• 2013

Objectives: This study evaluated the effects of intraradicular moisture on the pushout bond strength of a fibre post luted with several self-adhesive resin cements. Materials and Methods: Endodontically treated root canals were treated with one of three luting cements: (1) RelyX U100, (2) Clearfil SA, and (3) G-Cem. Roots were then divided into four subgroups according to the moisture condition tested: (I) dry: excess water removed with paper points followed by dehydration with 95% ethanol, (II) normal moisture: canals blot-dried with paper points until appearing dry, (III) moist: canals dried by low vacuum using a Luer adapter, and (IV) wet: canals remained totally flooded. Two 1-mm-thick slices were obtained from each root sample and bond strength was measured using a push-out test setup. The data were analysed using a two-way analysis of variance and the Bonferroni post hoc test with p = 0.05. Results: Statistical analysis demonstrated that moisture levels had a significant effect on the bond strength of luting cements (p < 0.05), with the exception of G-Cem. RelyX U100 displayed the highest bond strength under moist conditions (III). Clearfil SA had the highest bond strength under normal moisture conditions (II). Statistical ranking of bond strength values was as follows: RelyX U100 > Clearfil SA > G-Cem. Conclusions: The degree of residual moisture significantly affected the adhesion of luting cements to radicular dentine.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.65-68
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• 2001

This study was conducted to develop a soil moisture meter using capacitance probe. A parallel cylinder type capacitance probe (C-probe) was fabricated The 5 MHz of crystal oscillator was constructed to detect the capacitance change of the C-probe with moist soil. A third order polynomial regression model for volumetric water content having oscillation frequency changes at 5 MHz as independent variables presented the determination coefficient of 0.979 and root mean square error of $0.031\;cm^{3}cm^{3}$ for all soil samples. A prototype soil moisture meter consisting of the sample container, C-probe, oscillator, frequency counter and related signal procession units presented the correlation coefficient of 0.987 and the root mean square error of $0.032\;cm^{3}cm^{3}$ as compared with the oven drying method for unknown soil samples.