• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3704-3712
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• 2012

Recently, antiwashout underwater concrete has been increasingly used for marine foundations of long span bridges. However, to shorten the construction period of antiwashout underwater concrete used in marine foundations, high fluidity antiwashout underwater concrete should be manufactured largely improving fluidity than the previous one. Thus, the objective of this experimental research is to suggest optimum mix proportions of high fluidity antiwashout underwater concrete. For this purpose, concrete specimens containing ground granulated blast furnace slag were manufactured according to the dosage of antiwashout admixture for unit binder contents of 550 and 600kg/$m^3$, respectively. And then, their quality performances such as slump flow, setting time, underwater segregation resistance, and ratio of compressive strength were evaluated according to the related specification of Korea Concrete Institute. It was observed from the test results that the minimum dosage of antiwashout admixture was necessary to satisfy the related specification.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.7
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• pp.889-895
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• 2007

This study investigated the quality characteristics of red ginseng cheonggukjang development by a various of concentration of red ginseng extract and powder to enhance its acceptability and functional properties. In the cheonggukjang added with red ginseng extract, viscous substances, reducing sugars, and fibrinolytic activity showed higher values by the addition of red ginseng extract. The standard crude saponin content of products containing red ginseng was evaluated, and found to be suitable in cheonggukjang added with 4% red ginseng extract. In the cheonggukjang added with red ginseng powder, viscous substances, reducing sugars, and fibrinolytic activity showed a similar tendency to the cheonggukjang added with red ginseng extract. Amino type nitrogen and ammonia type nitrogen decreased by increasing the addition of red ginseng powder, and the crude saponin content of cheonggukjang with the addition of 14% red ginseng powder was suitable, in terms of manufacturing standards for products containing red ginseng. Dependent on the addition time of red ginseng in cheonggukjang, viscous substances, reducing sugars, fibrinolytic activity, amino type nitrogen, and ammonia type nitrogen showed no differences based on the addition time; however, for crude saponin content, the cheonggukjang with red ginseng added before fermentation showed a higher saponin content than the cheonggukjang with red ginseng added after fermentation. The ginsenosides $Rg_{1}$, Re, Rf, $Rh_{1}$, $Rg_{2}$, $Rb_{1}$, Rc, $Rb_{2}$, Rd and $Rg_{3}$ were detected, but ginsenoside content did not show significant difference according to addition time. In conclusion, the addition amount of red ginseng in cheonggukjang for optimum fermentation was concentration of 4% (w/w), which showed the best results in quality characteristics.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.111-122
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• 2012

Establishment of the LFQC (Liquid Fertilizer Quality Certification) system is very urgent issue for recycling livestock manure as renewable resources in Korea faced with environmental problem of manure application to land due to intensive livestock farming. In this study, we investigated relevant laws and regulations on livestock manure fertilizer, certifications of eco-friendly agricultural products, government policies on livestock manure management to establish reasonable direction of Korean LFQC (Liquid Fertilizer Quality Certification) system. As a result from this study, the liquid fertilizers in 'LFQC' system could be classified as three levels according to the usage patterns in field; 1st. Individual Farm Level (IFL), 2nd. Joint Farm Level (JFL), and 3rd. Commercial Level (CML). And finally, we found some characteristics in 'Main Level-Grading Factors' of liquid fertilizer such as fertilizing value, harmfulness, stability, uniformity, economic effect, storage potential, commercial value, functionality. Those items were considered to be the key factors for the establishment of 'LFQC' system. More research on 'Evaluation Standards' for concrete guideline and on the 'Main Level-Grading Factors' be needed to complete Korean LFQC system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.1
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• pp.132-137
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• 2010

This study was performed to investigate the effect of apple and maltitol as ingredients on the quality of Jochung, a grain syrup. Four kinds of Jochung products were prepared from steamed-rice, apple juice, heated-apple sarcocarp (at $70^{\circ}C$, 60 min), and a mixture (sarcocarp : maltitol＝5:1, w/w) by saccharifying (at $55^{\circ}C$, 8 hrs) with a malt (100 g/500 g rice), mixing the ingredients (steamed-rice : ingredient＝5:5, w/w), filtering, and heating the filtrate (at $95^{\circ}C$, 2 hrs): product (A) with apple juice added before saccharified, product (B) with apple juice added after saccharified, product (C) with heated-apple sarcocarp added after saccharified, and product (D) with the mixture added after saccharified. The product (D) had the lowest pH value ($4.60\pm0.01$) of any other products. The contents of reducing sugar and total phenolic compound were the highest in the product (A) among all the products, which comprised $68.10\pm6.71$% and $7.36\pm0.85$ mg/g, respectively, resulting in good quality. The solidity and the dextrose equivalence had the highest value in the product (B) and the product (C), respectively. The malic acid content ($4.10\pm0.02$%) of the product (D) was the highest of any other organic acids identified by HPLC. Hunter L, a, and b values of the product (D) were the highest compared to other products. In sensory evaluation, the product (A) had generally higher score in all sensory attributes. It was concluded from the chemical and sensory evaluation that adding the apple juice before saccharified might be an effective method for manufacturing good quality rice-Jochung.

• Journal of the Korean GEO-environmental Society
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• v.13 no.7
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• pp.5-12
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• 2012

Recently the installation of reinforced earth retaining walls in the domestic construction site has increased, surpassing conventional RC walls. These reinforced walls have various types depending on the reinforcing material, installation method and the form of face panel. However, there are difficulties in design and construction management due to the unproved safety of construction method. In case of reinforcing materials, despite the fact that they come in all different sizes and types produced by small businesses or partially imported with cheap price and low quality, no proper standards for designing the walls have been suggested. In order to apply reinforced retaining wall system to broad cases and design the walls effectively considering site conditions, specific design and construction guidelines for efficient construction management are needed. In conclusion, this study verified that reduction factors can be greatly affected by grain sizes and stiffness of backfill materials and granularity range, therefore in case of relatively large construction site, it is required to redesign the reinforced retaining wall by evaluating site installation resistance test, applying respective reduction factors to each backfill material and select the right geogrid depending on the usage of retaining wall so as to enhance the safety of reinforced earth retaining walls with efficiency.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.7 no.4
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• pp.673-680
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• 1997

NaOH, $Na_2CO_3, CaO, Ca(OH)_2$ and $CaCO_3$ are widely used counteractives for neoutralizing the waste sulphuric acid produced during the metal surface treatment process and/or the metal refining process. To reduce the tremendous expenses for the neutralization treatment of the waste sulphuric acid, the sludge from calcination plant and the stainless refining dust in POSCO (Pohang Iron ＆ Steel co. Ltd.) was utilized. For the sludge, it will be effective to use calcined and then hydrated sludge in strong acid region (pH<2) and to use the sludge itself in weak acid region (pH>2), The gypsum, the by-product of this treatment, was tested to fit the industrial standard of gypsum, so it is expected that it will solve the lack of gypsum supply. For the stainless refining dust, the phase and the morphology of produced gypsum from waste suiphuric acid neutralization was compared with those from pure sulphuric acid. Because of high reactivity and reaction temperature, $CaSO_4$ non-hydrate was obtained in pure sulphuric acid. But $CaSO_4$ dihydrate was obtained in waste sulphuric acid. It is also judged to be a good material for a counteractive of the waste sulphuric acid.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.4
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• pp.519-523
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• 2005

Soybean paste (Doenjang) was prepared by adding Lotus root powder (LRP) at $5\~15\%$ (w/w) to improve quality of the Doenjang and to give some functional properties. Moisture content was ranged about $50.05\~54.04\%$ and amino nitrogen content was $635\~648\;mg\%$ following the LRP contents. Crude protein amounts were $11.55\~12.56\%$ that was no difference between test samples. Carbohydrates contents increased $1.5\~2$ times in the test samples than the control depending on the LRP contents. However, contents of crude lipid $(6.99\~8.55\%)$ and ash $(13.99\~15.17\%)$ were decreased as increased the amounts of LRP. The pH of the product was decreased until 45 days during aging period and then slightly increased without significantly differences among test samples. The values of acidity were $1.85\~2.18\%$ at the early stage of aging but slightly increased with further aging. The total phenolic content in the Doenjang adding $15\%$ LRP was $461.8\;mg\%$ which is higher than $368.6\;mg\%$ in the control. Doenjang prepared with LRP showed an anti-browning effect of the product itself.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1412-1419
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• 2006

Concentrations of formaldehyde and acetaldehy de were respectively analysed in forty-five alcoholic beverages obtained from the market. After derivatization with PFBHA, GC-ECD and GC-MSD were employed for analysis. The peak area of aldehyde oximes (derivatives with PFBHA) increased with the increasing ethanol content (5%, 10%, 15%, 20% and 40%). When three-point calibration corves for the selected ethanol concentration (5, 13, 21 and 40%, v/v) were studied, suitable linearity against ethanol concentration was observed only under 5, 13, and 21% (ethanol, v/v). After analysis, maximum content of formaldehyde (average of 0.272 ppm) and acetaldehyde (average of 15.262 ppm) among the observed 45 alcoholic beverages was found from whisk (2 species) while minimum content of formaldehyde (average of 0.009 ppm) and acetaldehyde (average of 0.805 ppm) was found from diluted soju (4 species).

• Food Science and Preservation
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• v.24 no.6
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• pp.865-870
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• 2017

Yogurt is produced by fermentation of milk using bacteria known as "yogurt cultures". Most of these bacteria are probiotics such as Lactobacillus delbrueckii subsp. bulgaricus, Lb. rhamnosus, Streptococcus thermophilus, and Bifidobacterium. The domestic fermented milk market is increasing, and about 30 companies are producing yogurt. The purpose of this study was to analyze the quality characteristics of domestic commercial liquid yogurt. Total 30types of commercial yogurts were sampled and their physicochemicial properties, including pH, sugar content, acidity, viscosity, and microbial characteristics of lactic acid bacteria counts, were measured. Commercial liquid type yogurt showed a pH of 4.5, sugar content of 7.4-21.2%, total acid content of 0.4-0.9%, and viscosity of 0.1-250 cP. In terms of microbial populations, lactic acid bacteria counts were 7.2-11.3 log CFU/mL and anaerobic lactic acid bacteria counts were 8.0-11.5 log CFU/mL. The quality characteristics differed depending on the constituents of the sample and the microorganisms used. These results are related to the quality characteristics of yogurts and are useful for identifying new trends in the domestic fermented milk industry.

• Journal of Korean Society of Forest Science
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• v.24 no.1
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• pp.45-52
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• 1974

This study was carried out to examine the subsitution possibility into water soluble amino resins instead of phenolic resin as a sizing material for the strength increase on the wet forming hardboard. The properties of hardboard, manufactured with amino-resins based urea, melamine, formaline, and methanol which were low priced domestic products, were examined in comparison with those of hardboard treated with phenolic resin. In this study by the results and discussions, it may be summarized as follows: 1. Amino-resins are able to be substituted for the phenolic resin as a good sizing material for strength increase in the manufacture of wet forming hardboard. Under the considerations of economic advantages and properties of hardboard, modified urea-melamine resin was given a best results. 2. The specific gravities of hardboard that were treated with phenolic resin was equal to that treated with modified amino type resin, and in case of urea-melamine resin, the specific gravity value were lowest among them. 3. The results of moisture contents were satisfied the standard which calls for 13 percent or below. There were no differences in moisture contents between hardboards, treated with melamine resin and modified urea-melamine resin but phenolic resin. The moisture contents of hardboard treated with phenolic resin was shown the lowest. 4. The water absorption of hardboard treated with phenolic resin was greater than those treated with amino resins, and to satisfy the standard of water resistance, the treatment of 2 percent paraffin wax emulsion was needed in this case. There were no differences in water absorptions between hardboards, treated with melamine resin and modified urea-melamine resin. To satisfy the standard of water resistance in this case the treatment of 1 percent paraffin wax emulsion was shown good results. 5. The differences among the flexural strength in using tested three adhesives were significant. The flexural strength were shown the signification by order of melamine resin, modified urea-melamine resin, and phenolic resin. In all cases to satisfy the standard of flexural strength, the treatment of 3 percent sizing materials for strength increase was needed.