• Tribology and Lubricants
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• 제32권2호
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• pp.67-71
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• 2016

This study investigates the characteristics of the sapphire wafer chemical mechanical polishing (CMP) process. The material removal rate is one of the most important factors since it has a significant impact on the production efficiency of a sapphire wafer. Some of the factors affecting the material removal rate include the pressure, platen speed and slurry. Among the factors affecting the CMP process, we analyzed the trends in the material removal rate and surface roughness, which are mechanical factors corresponding to both the pressure and platen speed, were analyzed. We also analyzed the increase in the material removal rate, which is proportional to the pressure and platen speed, using the Preston equation. In the experiment, after polishing a 4-inch sapphire wafer with increasing pressure and platen speed, we confirmed the material removal rate via thickness measurements. Further, surface roughness measurements of the sapphire wafer were performed using atomic force microscopy (AFM) equipment. Using the measurement results, we analyzed the trends in the surface roughness with the increase in material removal rate. In addition, the experimental results, confirmed that the material removal rate increases in proportion to the pressure and platen speed. However, the results showed no association between the material removal rate and surface roughness. The surface roughness after the CMP process showed a largely consistent trend. This study demonstrates the possibility to improve the production efficiency of sapphire wafer while maintaining stable quality via mechanical factors associated with the CMP process.

• Journal of Radiation Protection and Research
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• 제37권4호
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• pp.231-236
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• 2012

This study derived measures to reduce exposure doses by identifying factors which affect the external radiation dose rate of patients treated with radiopharmaceuticals for PET-CT tests. The external radiation dose rates were measured on three parts of head, thorax and abdomen at a distance of 50cm from the surface of 60 PET-CT patients. It showed there are changes in factors affecting the external radiation dose rate over time after the administration of F-18 FDG. The external radiation dose rate was lower in the patients with more water intake than those with less water intake before the injection of radiopharmaceuticals at all three points: right after the injection of radiopharmaceuticals (average 4.17 mins), after the pre-PEET-CT urination step (average 77.47 mins), and right after the PET-CT test (average 114.15 mins). The study also found there is a need to increase the amount of water intake before the injection of radiopharmaceuticals in order to maintain a low external radiation dose rate in patients. This strategy is only possible under the assumption that the quality of the video has not changed after conducting this study on the relations between the image and quality. This study also found a need to use radiopharmaceuticals with the minimum amount needed for each patient because F-FDG doses affects the external radiation dose rate at the point right after the injection of radiopharmaceuticals. Urination frequency was the most significant factor to affect the external radiation dose rates at the point right after the PET-CT test and the point after the pre-PET-CT urination step. There is a need to realize the strategy to increase the urination frequency of patients to maintain the external radiation dose rate low (average 77.47 mins) before and after the injection of radiopharmaceuticals. In addition, at this point, there is a need to take advantage of personal strategies because the external radiation dose rate is lower if the fasting time is shorter, the contrast medium is used, and the amount of water intake is increased after the administration of radiopharmaceuticals. Finally this study found the need to be able to generalize these findings through an in-depth research on the factors affecting the external radiation dose rate, which includes radiopharmaceutical dose, urination frequency, the amount of water intake, fasting time and the use of contrast medium.

• 한국유기농업학회지
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• 제9권4호
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• pp.123-134
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• 2001

The quality including in situ degradability in the rumen of Holstein of the black locust silage added with apple pomace was investigated in this study. The amount of apple pomace added in different treatments were 0, 20, 40 and 60% respectively. With higher amount of addition of apple pomace in black locust, crude protein content in the silage decreased. Crude protein contents in the apple pomace added silage were in the range between 11.7 and 13.7% and those were significantly lower than 16.3% of 100% black locust silage. The contents of ADF, NDF and crude ash were in the same trend as with crude protein, which were shown more clearly in the 40∼60% addition of apple pomace. Moisture content of 100% black locust silage was 56.7% however it significantly increased according to higher levels of addition of apple pomace(67.1∼73.8%). pH, lactic acid and total organic acid contents in 20∼60% addition of apple Pomace were 3.7∼4.3, 1.3∼2.2%, and 2.1∼6.0% respectively, however in 100% black locust silage those were significantly lower except pH as 5.4, 0.6% and 1.0% respectively. In situ disappearance rates of dry matter and NDF in the rumen were significantly higher at the stapes of incubation after 12h and 24h respectively in 20∼40% addition of apple pomace than in 100% black locust silage. No statistical differences were observed with quickly degradable fraction (a) in the disappearance rates of dry matter and NDF. In dry matter, however slowly degradable fractions (b) of 100% black locust and 60% addition of apple pomace were significantly higher as 99.7 and 99.8% respectively than 37.7∼50.5% of 20∼40% addition of apple pomace. On the contrary, fractional rate of disappearance (c) and effective degradability(ED) were significantly higher in 20∼40% addition of apple pomace as 0.0115∼0.0149 and 30.4∼31.9% respectively than the respective values of 0.0027 and 24.9% of 100% black locust. In NDF, b was significantly higher in apple pomace added silage(38.5∼99.8%) than in 100% black locust silage(14.9%). However, C was significantly lower in apple pomace added silage than in 100% black locust silage.

• Asian-Australasian Journal of Animal Sciences
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• 제11권3호
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• pp.277-284
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• 1998

This experiment was carried out to study the effects of lactic acid bacteria (LAB) inoculation and addition of cell wall degrading enzymes on the fermentation characteristics and chemical compositions of Italian ryegrass silage. An inoculant LAB with or without a cell wall degrading enzyme of Acremoniumcellulase (A), or Meicellulase (M) or a mixture of both (AM), was applied to 1 kg of fresh Italian ryegrass sample. The treatments were control untreated, LAB-treated (application rate $10^5$ cfu/g fresh sample), LAB+A 0.005%, LAB + A 0.01%, LAB+A 0.02%, LAB + M 0.005%, LAB + M 0.01%, LAB + M 0.02%, LAB+AM 0.005%, LAB + AM 0.01% and LAB+AM 0.02%. The sample was ensiled into 2-L vinyl bottle silo, with 9 silages of each treatment were made (a total of 99 silages). Three silages of each treatment were incubated at 20, 30 and $40{^{\circ}C}$ for an approximately 2-months storage period. All silages were well preserved as evidenced by their low pH values (3.79-4.20) and high lactic acid concentrations (7.71-11.34% DM). The fermentation quality and chemical composition of the control untreated and the LAB-treated silages were similar, except that for volatile basic nitrogen (VBN) content was lower (p < 0.05) in the LAB-treated silages. LAB + cellulase treatments improved the fermentation quality of silages by decreasing (p < 0.01) pH values and increasing (p<0.01) lactic acid concentrations, in all of cellulase types and incubation temperatures. Increasing amount of cellulase addition resulted in further decrease (p < 0.01) of pH value and increases (p < 0.01) of lactic acid and residual water soluble carbohydrate (WSC) concentrations. LAB + cellulase treatments reduced (p<0.01) NDF, ADF, hemicellulose and cellulose contents of silages compared with both the control untreated and LAB-treated silages. LAB + cellulase treatments did not affect the silage digestibility due to fact of in vitro dry matter digestibility (IVDMD) was similar in all silages. The silages treated with cellulase A resulted in a better fermentation quality and a higher rate of cell wall reduction losses than those of the silages treated with cellulases M and AM. Incubation temperature of $30{^{\circ}C}$ seemed to be more suitable for the fermentation of Italian ryegrass silages than those of 20 and $40{^{\circ}C}$.

• 한국식품조리과학회지
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• 제21권5호
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• pp.655-661
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• 2005

흑임자 가루를 지방대체물 및 영양강화의 목적으로 2.5, 5.0, 75% 첨가하여 제조한 식빵의 품질 특성을 조사한 결과는 다음과 같다. 1. 무게는 대조군 516.0 g에 비해 첨가군은 $522.0{\sim}532.0\;g$으로 흑임자 첨가량이 증가할수록 유의적으로 증가하였고, 부피는 대조군 2,180 mL, 첨가군은 $2,250{\sim}1,800\;mL$로 흑임자 첨가량이 증가할수록 유의적으로 증가하다 감소하였다. 2. 수분흡수력은 대조군이 5.28, 첨가군은 $3.83{\sim}2.48$로 흑임자 첨가량이 증가할수록 유의적으로 감소하였으며, pH는 대조군이 5.35, 첨가군은 $5.43{\sim}5.53$으로 유의적으로 증가하였다. 3. 색도 L 값은 대조군에서 76.63, 첨가군에서 $71.13{\sim}59.90$으로 흑임자 첨가량이 증가할수록 유의적으로 감소하였으며, a 값은 대조군에서 2.00, 첨가군에서 $1.08{\sim}0.75$로 흑임자 첨가율이 증가할수록 낮아졌으나 유의적인 차이는 없었다. b 값은 대조군이 13.13, 첨가군에서는 $11.30{\sim}9.60$으로 첨가량이 증가할수록 유의적으로 낮아졌다. 4. 조직감에 있어서 경도의 경우 대조군이 0.063, 첨가군은 $0.063{\sim}0.107\;kg$으로 7.5% 첨가군에서 유의적으로 증가하였고, 진입력은 대조군 0.029, 첨가군은 $0.041{\sim}0.062\;kg$으로 유의하게 증가하였다. 5. 관능검사에서 향미는 대조군이 4.2, 첨가군이 $3.7{\sim}3.1$로 흑임자 첨가량이 증가할수록 유의적으로 감소하였고, 조직의 촉촉한 정도는 대조군이 4.9, 첨가군이 $3.9{\sim}2.6$으로 흑임자 첨가량이 증가할수록 유의적으로 감소하였다. 색상, 맛 씹힘성은 시료간에 유의적인 차이가 없었으며 전반적인 기호도는 2.5% 첨가군이 4.0으로 가장 높았으나 유의적인 차이는 없었다.

• 한국식품조리과학회지
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• 제21권5호
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• pp.669-676
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• 2005

클로렐라 가루를 0, 2, 4, 6%로 각각 달리 첨가하여 제조한 파운드케이크의 품질 특성을 조사하였으며 그 결과는 다음과 같다. 1. 반죽의 pH는 대조군이 7.08, 첨가군은 각각 7.13, 7.10, 7.10으로 pH가 증가하다가 감소하였다. 2. 중량은 대조군이 392.0 g, 첨가군은 각각 392.4, 389.2, 384.2 g으로 감소하였고, 부피는 대조군이 760.8 mL, 첨가군에서는 각각 801.8, 806.4, 839.2 mL로 유의적으로 증가하였다. 3. 부피지수와 굽기손실률은 클로렐라 첨가군에서 증가하는 경향이었고 수분흡수력은 클로렐라 첨가량이 증가함에 따라 유의적으로 증가하였다. 4. 경도는 1시간 방냉 시료의 경우 대조군이 0.74, 첨가군은 각각 0.67, 0.63, 0.65 kg으로 낮아졌고, 진입력은 대조군이 0.22, 첨가군이 $0.26{\sim}0.32\;kg$으로 높아졌으나 유의적 차이가 나타나지 않았다. 5. 색도에서 L값은 대조군 69.88에 비하여 클로렐라 첨가량이 많을수록 유의적으로 낮은 값을 나타내었고, a 값은 클로렐라 첨가량이 많을수록 음의 값을 나타내었으며 유의적인 차이를 보였다. 또한 b 값은 클로렐라 첨가량이 증가할수록 낮아지는 경향을 나타내었으며 유의적인 차이를 보였다. 6. 관능검사 결과 색상은 대조군 3.9, 첨가군이 $3.4{\sim}2.5$로, 냄새는 대조군 3.7, 첨가군이 $3.3{\sim}3.0$으로 유의적인 감소를 보였다. 맛과 전체적 기호도는 6% 첨가군에서 각가 2.8, 2.6으로 다른군에 비해 유의적으로 낮아졌다. 촉촉함과 씹힘성은 시료간에 유의적인 차이가 없었다.

• 한국식품조리과학회지
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• 제26권5호
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• pp.586-595
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• 2010

This study was conducted to examine the quality characteristics of tofu prepared with Lycii fructus powder(LFP) during storage for 15 days at $5{\pm}1^{\circ}C$. The moisture content, yield rate, tofu whey content and turbidity of soaking solutions of tofu prepared with LFP increased upon the addition of LFP. The pH of tofu prepared with LFP decreased while the acidity increased lightly; however, the acidity of the tofu did not differ significantly according to the level of added LFP. The L value of tofu decreased as the amount of LFP in the formulation increased, whereas the a and b values increased. The color value of tofu prepared with LFP did not depend upon the storage period. The hardness increased significantly with the level of LFP, but it did not differ significantly according to the storage period. The microbial count of tofu prepared with LFP was lower than that of control tofu during the storage period. In terms of overall preference, the preferred tofu contained 1.0% LFP tofu.

• 한국축산식품학회지
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• 제38권2호
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• pp.273-281
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• 2018

Preheating conditions (low-, medium-, and high heat-) did not significantly affect the buffering capacity (BC) of skim milk powder (SMP), whereas the level of demineralization significantly affected the BC of whey powders (WP). Heat treatment ($85^{\circ}C$ for 30 min) of both SMP and WP (90% demineralized) mixtures (88:12, 76:24, 64:36 and 52:48; SMP:WP) resulted in a reduced BC, and the extent of this reduction increased with the proportion of WP increased in the samples. High-buffering milk prepared by the addition of phosphate salts (40 mM $NaH_2PO_4$ and 60 mM $Na_2HPO_4$) delayed the rate of pH decline during yoghurt fermentation. The high-buffering yoghurt showed a significantly higher water holding capacity (WHC) than that of control yoghurt (p<0.05), as well as a more uniform and interconnected microstructure with small pore sizes than those of control yoghurt. No significant differences were found between high-buffering and control yoghurt regarding the viable bacterial counts of starter. The manipulation BC can potentially improve the quality characteristics of yoghurts, such as WHC and texture.

• 한국수산과학회지
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• 제36권4호
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• pp.333-339
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• 2003

New manufacturing process was applied to manufacture the low salted Squid-Jeotgal to improve the quality variation salty taste and shelf-life. It's optimum salting and sugaring process was made by the addition of $17\%$ NaCl for 3 hr and $15\%$ corn syrup for 4 hr with 10 rpm agitation. Quality variations of Squid-Jeotgal produced by the improved and the conventional process were packed by jar, polyethylene lerephthalatefpolyethyleneilinear low density polyethylene (PET) and low density polyethylene (PE). And then quality variations of them were investigated at storage temperature of 10, 20, and $30^{\circ}C.$ Decreasing rate of pH, increasing rates of VBN and viable cell counts of Squid-Jeotgal produced by the improved process were slower than those of the conventional process at all storage temperature. Sensory evaluation indicated that the production of Squid-Jeotgal by the improved process extended the shelf-life about 10-20 days.

• Environmental Engineering Research
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• 제16권2호
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• pp.97-102
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• 2011

This study investigates the treatment of pigment wastewater using a sequential batch reactor (SBR) followed by dissolved ozone flotation-pressurized ozone oxidation treatement (DOF-$PO_2$). The process efficiency has been evaluated at the lab scale on the basis of water quality parameters. In addition, the effect of pure oxygen and air was investigated on the removal of COD, BOD, and TN in the SBR process. It was observed that under comparable conditions the removal efficiencies of these water quality parameters using pure oxygen and air were similar. The effect of the recycle rate was also investigated for its impact on the water quality parameters using different ozone dissolving pressures in a DOF process in order to optimise conditions. The results conclude that the use of an SBR and ozone contact by DOF-$PO_2$ is a highly effective treatment for pigment wastewater and aids in the achievement of effluent discharge criteria.