• Journal of the Korean Crystal Growth and Crystal Technology
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• v.30 no.4
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• pp.156-161
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• 2020

Recently, as there has been growing demand for aesthetic quality in structural materials, the development of excellent color cement concrete having good coloration properties has become a requirement. This study is designed to analyze the basic physical properties of mortar and the properties of keeping the coloration under an ultraviolet ray accelerated weathering test environment according to changes in the mixing ratio between carbon black and iron oxide used as colorants. The test results show that the use of carbon black and iron oxide reduces the initial flow by 6.3~17.2 % and the air content by 3.5~31.5 % but increases the unit volume weight by 3.4~5.5 %, compared to ordinary Portland cement (OPC). In addition, the study shows that the addition of iron oxide increases the self drying shrinkage. So, caution needs to be taken on the workability of the concrete. The brightness value L^⁎ represented by black showed the most excellent black colour when carbon black 3 % and iron oxide 5 % are added. According to UV accelerated weatherproof test, the brightness value L^⁎ was found to increase in all experiment specimens by 4.28~11.97 %, and the color change by UV was found to be higher for the case where carbon black colorant was not used. Therefore, in terms of color revelation characteristics, the case using carbon black 3 % and iron oxide 5 % was found to show the best black color.

• Journal of the Korean GEO-environmental Society
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• v.9 no.6
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• pp.31-41
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• 2008

Consolidation characteristics of reclamated ground with dredged soil and methods of evaluating them are investigated in this paper. For a dredged and reclamated ground with a very high water content, self-weight consolidation being progressed, its consolidation characteristics are difficult to find since it is almost impossible to have a undisturbed sample. In order to overcome such a problem, methods of laboratory tests with disturbed sample were studied to obtain consolidation parameters required to analyze consolidation settlement in practices, using the conventional infinitesimal consolidation theory, were evaluated by carrying out various laboratory tests with disturbed soils such as oedometer test, constant rate of deformation test, Rowe-cell tests with ring diameters of 60 mm, 100 mm and 150 mm and the centrifuge model tests with 40 g-levels. Constitutive relations of void ratio - effective vertical stress - permeability were evaluated by using the inverse technique implemented with the finite strain consolidation theory and results of centrifuge model tests. Design soil parameters related to consolidation such as compression index, swelling index, coefficient of volume change and vertical and horizontal consolidation coefficients were proposed properly by analyzing the various test results comprehensively.

• Culinary science and hospitality research
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• v.18 no.1
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• pp.1-14
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• 2012

This study examines the physiochemical and quality properties of the bread added with soy fiber powder to promote the intake of soy fiber. For this study, the powder for making bread was mixed with soy fiber, wheat flour and SF-1450 and SF-1260 at the ratio of 0~12% each. The ratios of the edible fiber contained in the soy fiber power samples were 72.0% in the SF-1450 sample and 67.8% in the SF-1260 sample. The mixograph characteristics tended to be conspicuons in proportion to the amount of the soy fiber added at midline peak height, width at peak and, width at 8.00. The specific volume of the bread tended to decrease significantly as the amount of the soy fiber increased from 2 to 12%. In terms of crust chromaticity change, L-value increased more significantly in the samples added with 4 to 12% than the control. For a-value, SF-1450 in the samples with 6 to 12% and SF-1260 in the samples with 8 to 12% more significantly decreased than the control. For such characteristics of texture as hardness, SF-1450 in the samples with 10 to 12% and SF-1260 in the samples with 6 to 12% increased more than the control. As discussed above, the sensual characteristics of the white pan bread with soy fiber added tended to be worse as the amount of the additive increased, compared with the control samples. Summing up the results of the physico-chemical analysis and the overall acceptability, those samples with 2~4% of SF-1450 and 2% of SF-1260 were found excellent.

• KSBB Journal
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• v.4 no.1
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• pp.21-30
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• 1989

Lauryl alcohol was used as extracting solvent of ethanol, and its toxicity on the free cells or immobilized cells was tested. To increase ethanol productivity, extractive fermentation method combined with ethanol fermentation and ethanol recovery was applied to the immobilized batch and continuous fermenter. As the concentration of LaOH was increased, the lag phase became longer, but specific growth rate did not change greatly. And a cell entrapment technique could protect the yeast cells against both substrate inhibition and solvent toxicity. When the glucose concentration was 400 g/l and the LaOH/fermentation medium ratio was 4, total ethanol productivity increased with the enhancement of LaOH volume, and maximum productivity was 2.75 g/l.hr in the immobilized batch fermentation.

• Atmosphere
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• v.29 no.4
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• pp.403-416
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• 2019

Precipitation samples were collected at the GAW Stations in Anmyeon-do and Gosan for 10 years (2008-2017) to analyze pH, electrical conductivity and NH₄⁺, Na⁺, K⁺, Mg²⁺, Ca²⁺, SO₄^2-, NO₃^-, Cl^-, and F^- ions. From the analysis, the correlation between pH and rainfall, the composition of precipitation and comparison with other regions, and the results of neutralization characteristics by seasonal and pH were determined. In the comparison of ion balance and conductivity for the validation of analytical data, the correlation coefficients were within the range of 0.996~0.999, implying good linear relationship. The volume-weighted pH of the Anmyeon-do and Gosan areas were 4.7 and 4.9, respectively. The pH of the rainfall was affected by washout and rainout in both areas. The ionic strength of precipitation at Anmyeondo and Gosan were 0.42 ± 0.63 mM and 0.37 ± 0.75 mM, indicating about 27.6% and 35.3% of the total precipitation as per a pure precipitation criterion (10^-4 M), respectively. The composition ratio of ionic species were 44.7% and 57.5% for marine sources (Na⁺, Mg²⁺, Cl^-), 40.6% and 22.2% for the secondary inorganic components (NH₄⁺, nss-SO₄^2-, NO₃^-), and 5.6% and 4.0% for the soil source (nss-Ca²⁺), respectively. The neutralization factor of Anmyeon-do and Gosan were 0.43~0.65 and 0.34~0.48, and the neutralization factors of calcium carbonate were 0.15~0.34 and 0.25~0.30, respectively. Thus, both regions have the highest rate of neutralization caused by ammonia. As pH increased in Anmyeon-do and Gosan, change in calcium carbonate became greater than that in ammonia.

• Journal of Chest Surgery
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• v.13 no.2
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• pp.85-91
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• 1980

Extracorporeal circulation by hemodilution technique has been currently used with its clinical safety and good peripheral tissue perfusion in open heart surgery. There is no doubt that $O_{2}$ carrying capacity of the blood is disturbed by decreased hemoglobin level resulting from hemodilution of the circulating blood. From the view point of the blood gas exchange, these experimental studies were undertaken to determined the sate limit of hemodilution in the condition of cardiopulmonary bypass with a constant perfusion flow rate. Twelve adult mongrel dogs weighing 10 to 13 Kg. were anesthetized with pentobarbital and then respiration was controlled with Harvard volume respirator using room air. The cardiopulmonary by pass was performed by use of Sarns heart lung machine (console 5000, 5 head and 2 roller pumps) and Travenol pediatric bubble oxygenator. The perfusion rate during bypass was maintained at a constant rate of 80 ml/min/Kg of body weight. The ratio of oxygen gas flow to blood flow was kept in 3 to 1 constantly. International hemodilution was attained by serial blood withdrawals and immediate infusion of equal volumes of diluants composed of Ringer's lactate, 5% dextrose in water and 25% mannitol solution, proportionally 60%, 30%, and 10%. Arterial and venous blood samples were obtained between 15 and 20 minutes following each hemodilution. Hematocrits and hemoglobin values, $PO_{2}$, $PCO_{2}$ and pH were measured. Oxygen and carbon dioxide contents oxygen consumption and carbon dioxide elimination were calculated groups according to different hematocrit values and the correlations were evaluated. Result were as follows. 1. the arterial $O_{2}$ tension and $O_{2}$ saturation were maintained at the physiological level irrespective of the hematocrit value. 2. The venous $O_{2}$ tension and $O_{2}$ saturation showed a tendency to decline with the decrease in hematocrit value and positive correlation between them (r = +0.49, r = +0.76), The mean values of venous $O_{2}$ tension and $O_{2}$ saturation, however, were not decreased when the hematocrit levels were lower than 20%. 3. The arterial $O_{2}$ content declined lineally in proportion to the fall of hematocrit level with a positive correlation between them (r = +0.95). 4. The venous $O_{2}$ contents were decreased gradually as the hematocrit value decreased with positive correlation between them ( r =+0.89). The trend of diminution of venous $O_{2}$ content, however, was became low according to progressive decrease of hematocrit level. 5. Systemic oxygen consumption was in higher range than $O_{2}$ requirement of basal metabolism when the hematocrit value was above 20%, but abruptly decreased when the hematocrit value became to below 20%. 6. The arterial $CO_{2}$ tension and $CO_{2}$ content showed trend of increasing with progressive decrease of hematocrit value but exhibited a rather broad range and there was no relationship between those value and the hematocrit value. 7. The venous $CO_{2}$ tension and $CO_{2}$ content have also no correlation with change of Ht. value but related directly to those value of arterial blood with positive correlation between them (r = +0.78, r = +0.95_. 8. A-V difference of $CO_{2}$ content and $CO_{2}$ elimination wasnot significantly influenced by Ht. value. From the results, we obtained that feasible limit in inteneional hemodilution is above the hematocrit value of 20% under the given experimental condition.

• The Journal of Engineering Geology
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• v.15 no.2 s.42
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• pp.145-154
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• 2005

This study conducted to develop an assessment method of runout distance of debris flow that is a major type of landslides in Korea. In order to accomplish the objectives, this study performed detailed field survey of runout distance and laboratory soil tests using 24 landslides over three pilot sites. Based on the data of the field survey and the laboratory tests, an assessment method of runout distance was suggested using the artificial neural network. The input data for the analysis of artificial neural network are change rate of slope angle, Permeability coefficient of in-situ soil, dry density, void ratio, volume of debris and the measured runout distance. The analyzed results using the artificial neural network show low error rate of inference distributing lower than $10\%$. Some cases have $5\%$ and $2\%$ of error rates of inferences. The results can be thought as excellent teaming rates. However, it is difficult to be accepted as excellent results if it is considered with the results derived using only 24 landslide data. Therefore, more landslide data should be surveyed and analyzed to increase the confidence in the assessment results.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.357-365
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• 2002

A survey was under taken of six district of Northern India viz. Bareilly, Pilibhit, Udham Singh Nagar, Nainital, Almora and Rampur. The age, breed, sex and physiological status recorded. A total number of 854 cattle examined out of which lactating (274 cases), non lactating (302 cases) heifers (128 cases), calves (82 cases) and adult male (68 cases) were examined. An incidence of 4.92 percent (42) of microfilarisis was recorded. The highest prevalence was observed in Rudrapur District of Udham Singh Nagar (33.33%, 4/12), followed by Lalkaun in Nanital District (21.74%, 10/46), Rampur (12.50%, 2/16), Bareilly (8.16%, 8/98) and Pilibhit (1.22%, 1/82). No infection was observed in Almora region. Amongst 854 cattle of different group incidence was highest in adult male (12.20%, 10/82), followed by non lactating (3.82%, 12/314) and lactating (2.70%, 2/74), (7.64%, 12/157) was found in Heifers. For haemeto-biochemical, serum minerals estimations and therapeutic study 32 animals suffering from filariasis and 18 healthy animals were taken. 16 animals were treated with ivermectin $@200{\mu}g/kg $ body weight. Effect of this disease on production has also been estimated for which body weight and milk production was observed. The main clinical manifestations observed were anaemia, loss of appetite, debility, oedematous swelling especially in the abdominal region, increased heart rate, and respiration rate. Haematological changes indicated decrease in hemoglobin, total erythrocyte count, packed cell volume, erthrocyte fragility and neutrophil, whereas there was significant increase in erythrocytes sedimentation rate (ESR), total leukocyte count (TLC), lymphocyte and eosinophils. Biochemical changes showed significant reduction in the values of serum albumin, A : G ratio, where as there was significant increase in blood glucose, blood urea nitrogen (BUN), globulin, total lipid, total cholesterol, phospholipids, serum bilirubin. Serum mineral profile also altered markedly, which indicate a significant decrease in Ca, Cu, Fe, Zn, and Mn with increase value of Na and Cl. There was no significant change in P and K values. Enzyme pattern in micro filaria infected animal indicated increased level of AST, ALT, alkaline phosphatase, ornithine carbamyl transferase, sorbitol dehydrogenase, glutamate dehydrogenase, isocitric dehydrogenase and lactate dehydrogenase. In blood gas values and acid/base balance, there was an increase in $PVCo_2$ and $PVo_2$. It has been observed that microfilaria infected cattle showed decrease in body weight and milk production. Animal treated with ivermectin showed the return of these above values toward normalcy.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.727-733
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• 2009

Effects of $Ca(OH)_2$ concentration(0.16~0.64 wt%), total volumetric flow rate(3~6 L/min) and $CO_2$ volume fraction(0.3~0.6) on morphology of the precipitated $CaCO_3$ and the mean particle size of the precipitated $CaCO_3$ were investigated in the slurry bubble column reactor. Experiments were carried out in acrylic reactor($0.11m-ID{\times}1.0m-high$) with a internal tube($0.04m-ID{\times}1.0m-high$). The calibration curve on the mass ratio of $CaCO_3$ to $Ca(OH)_2$ was obtained by FT-IR for the conversion of $Ca(OH)_2$ with the reaction time. The reaction rate of $Ca(OH)_2$ increased with increasing the volumetric flow rate of $CO_2$. From SEM images, the crystal size of $CaCO_3$ increased with increasing the reaction rate in the saturated concentration of $Ca(OH)_2$ (0.16 wt%). In addition, the crystal size of precipitated $CaCO_3$ decreased with increasing the concentration of $Ca(OH)_2$, but the mean particle size of precipitated $CaCO_3$ increased with increasing the concentration of $Ca(OH)_2$.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.4
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• pp.442-449
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• 2017

In this study, a method to inject small amount of activation agent from the outside of the pipeline to the inside wall of the pipe was newly proposed to enhance pumping efficiency of cementitious materials. The activation agent is injected into the slip-layer, which is generally formed in the vicinity of the inside wall of the pipe during pumping cementitous materials. Through the injections, it is expected to decrease viscosity of slip-layer, namely, the friction between the mateirals and the pipe. The proposed method was verified by lab-scale pumping tests with mortars having water to cement ratio of 47%. The tests were performed with two different type of activation agents(superplasticizer and anionic surfactant) and three different amount of the agents(0.14, 0.28, 0.42% of the mortar volume). The compressive strength were measured with and without injecting the activation agent, and the internal pressures of pipeline were measured. When the anionic surfactant was used, there was no change in the compressive strength. As the amount of anionic surfactant increased, the pumping pressure decreased up to 71.4% at the maximum.