• International Journal of Highway Engineering
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• v.13 no.1
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• pp.157-168
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• 2011

Recently, the cases of freeze-thaw distress on concrete pavement in domestic have been reported periodically. Hereupon, the necessity to establish the standard of spacing factor came to the fore. The test method for analyzing spacing factor is provided in the standard of ASTM C 457. Since researchers tend to judge study results subjectively, the results should be revised throughly. Image analysis program for determining the characteristics of air-void system on hardened concrete identify air void through the difference of a color. The pixel intensity values used in this program have a significant effect on the analysis results. This study compared the automated void count by varying pixel intensity values with the manual void count in order to determine the optimum range of pixel intensity values. Also, this study analyzed the air-void characteristics on eight kinds of concrete mixtures. In this study, it was confirmed that the variation of void counted manually was around 10% from the results of round robin test, and that the optimum range of pixel intensity values is around 80~90. And it was also confirmed that air content (as a whole) was increased generally and spacing factor was decreased by increasing air-entrainer content. But some concrete mixtures showed a tendency that air content was constant and spacing factor was decreased by increasing air-entrainer content. This causes the air entrained by air-entrainer has more influence on spacing factor than air content. Also, the deviation of spacing factor by cutting position of concrete specimen was about 30~100${\mu}m$ because of the limit of 2-D image analysis. The additional study about variation of spacing factor by cutting position of concrete specimen will be performed later.

• Journal of the Korean Wood Science and Technology
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• v.38 no.4
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• pp.333-340
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• 2010

The Korean Dendropanax lacquer, made from a natural resinous sap from Dendropanax orbifera Lev., was used as a golden and transparent varnish for the traditional artifacts (armor uits, helmets, arrowheads, etc.) to make them be brilliant golden color. The cured film of the acquer has excellent protective properties such as weatherability, water resistance, and nticorrosive. But, one of disadvantages is that takes a long time and much energy to fulfill curing the lacquer. The chemical constituents of the lacquer contained conjugated diene compounds s the photopolymerizable monomers. These monomers easily polymerized in sunlight to form olden-colored, hard-coating films in a short time. Photooxidation may be one of the most mportant reactions in the chemistry of the lacquer. Although the Korean Dendropanax Lacquer hould be dried to a thoroughly dry stage to achieve optimal film properties, curing with elevated emperatures may be required for the protracted curing time at atmospheric temperature. So we ntended to accelerate the curing rate of the lacquer by dual curing of thermal and radiation uring. The effect of thermal initiator on the thermal curing reaction was evaluated by monitoring he changes in double bond peak with FT-IR. Then the curing rate of the lacquer blended with hermal initiator and photoinitiator together was measured during dual curing using a RPT with V spot curing machine. Thermal initiator not only accelerated the curing rate but also improved he physical property. And the curing rate of the Korean Dendropanax lacquer was improved by ual curing method of thermal and UV curing. According to these results, the application area of he Korean Dendropanax lacquer could be expanded to surface coatings for electronic devices uch as mobile phones or electronics.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.168-177
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• 2009

This study was conducted to investigate the dietary effects of locally grown herbs (Mentha piperascens, PM; Rubus coreanus, RC; Tagetes patula, MG) on the growth performance and meat quality of broiler chicken. A total of 600 1-d-old Ross male broiler chicks were divided into eight groups and were fed control diets (antibiotics-medicated or non-medicated commercial diets) or experimental diets (non-medicated diets containing 0.3 or 0.5% PM, 0.3 or 0.5% RC, or 0.3 or 0.5% MG) for 5wk. The body weight gains and feed conversion rates (FCRs) in all the groups that were fed diets containing PM, RC, or MG were significantly improved compared to those in the non-medicated control group (p<0.05). The relative weights of various organs, the serum cholesterol levels, and the GOT/GPT activities in all the groups were also not significantly different. The superoxide dismutase (SOD)-like activities in the groups that were fed diets containing 0.3% PM or 0.3% MG were significantly increased compared to those in the non-medicated control group (p<0.05). The number of cecal lactic-acid bacteria in the groups that were fed diets containing 0.3% PM or 0.5% RC tended to increase. The malondialdehyde contents in the leg muscles were significantly lowered by feeding with PM or MG (p<0.05). The physicochemical properties of the edible meat, including the shear force, water-holding capacity, heat loss, pH, and muscle color degrees $(CIEL^*.\;a^*.\;b^*)$, were not affected by the dietary treatments. It has been suggested that spontaneous Korean plants promote the growth of broilers and may delay lipid oxidation in edible muscles without any negative effect when added in broiler diets.

• Food Science of Animal Resources
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• v.25 no.1
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• pp.20-25
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• 2005

This study was conducted to evaluate the effects of Zizyphus vulgaris supplementation on growth performance, blood cortisol and meat quality characteristics in finishing pigs. The total of thirty-six [Duroc${\times}$Yorkshir${\times}$Landrace] pigs ($91{\pm}2.11$ kg average initial body weight) were used in a 30-days assay. Dietary treatments included 1) CON (basal diet), 2) T1 (basal diet for 15 days and 0.1 % Zizyphus vulgaris for 15 days) and 3) T2 (0.1 % Zizyphus vulgaris for 30 days). The ADG (Average daily gain), ADFI (Average daily feed intake) and ADG/ADFI during the feeding period were not significantly differences among the treatments (p>0.05). Backfat thickness of pigs fed CON was higher than those of T1 and T2 (p<0.05). The appearance rate of A or B carcass grade was in T1 (74%) and T2 (84%) was significantly higher than that in CON (58%) (p<0.05). Pigs fed Zizyphus vulgaris 0.1 % for 30 days tended to decrease on blood cortisol compared with pigs fed CON and T1. But, there was not significantly difference among the treatments (p>0.05). The Hunter's L/sup */ (lightness) value of loin in the pork fed CON was higher than that of loin in the pork fed T1 and T2 (p<0.05). After 7 days, the L/sup */ value of loin in the pigs fed T2 was higher increased than that of pigs fed T1 and CON (p<0.05). However, a/sup */ and b/sup */ values were not affected by dietary Zizyphus vulgaris (p>0.05). There were not found remarkable differences in sensory properties (marbling, firmness and color) among the treatments. The results from the present study suggest that Zizyphus vulgaris could be a effective feed additive to improve meat quality of pigs. However, further research is needed to investigate effects of carcass characteristics.

• Microbiology and Biotechnology Letters
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• v.40 no.1
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• pp.43-49
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• 2012

In this study, we investigated the antibacterial activity and stability of a cream containing Hippophae rhamnoides leaf extract. The MIC values of ethyl acetate fraction from an H. rhamnoides leaf on Escherichia coli, Pityrosporum ovale, Propionibacterium acnes and Staphylococcus aureus were 0.5%, 0.25%, 0.25% and 0.06%, respectively. Stability evaluations, pH, viscosity and absorbance of the cream containing 0.25% ethyl acetate fraction of H. rhamnoides, were performed. The cream was measured under 4 different temperature conditions under sunlight at 2-week intervals for 12 weeks. The viscosity and pH were measured by a comparison of the experimental cream with a similar control cream. The H. rhamnoides extract was found to have contributed to the stability of the emulsion product via a protective effect in maintaining the viscosity of the cream against sunlight. The absorbance variations of the experimental cream at 270 nm were, under sunlight; $45^{\circ}C$, $37^{\circ}C$, $25^{\circ}C$, and $4^{\circ}C$. In addition, any change in color or smell was not observed through the 12 weeks of the experimental period. These results indicated that the cream containing 0.25% ethyl acetate fraction of H. rhamnoides leaf extract was stable. Accordingly, this suggests that further study is needed to provide additional information for manufacturers, who are seeking the application of the extract to improve anti-oxidant and antibacterial activities and the stability of cosmetic products.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.7
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• pp.1030-1037
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• 2010

A fresh juice has become a new functional food available for dieting and health. However, the shelf-life of vegetable juice is very short because of the absence of heat pasteurization process. To elongate the shelf-life of vegetable juices, such as Angelica keiskei and Brassica loeracea var. acephala, the changes of microbiological, chemical and sensory property by UV irradiation were investigated. The total aerobic bacterial numbers of A. keiskei and B. loeracea var. acephala vegetable juices were $3.2{\times}10^5$ and $7.0{\times}10^4\;CFU/mL$, respectively, after wring process. However, the numbers were $3.6{\times}10^3{\sim}9.7{\times}10^3$ and $3.7{\times}10^3{\sim}2.7{\times}10^4\;CFU/mL$ after UV treatment on wring juice, and this lower microbial number was maintained during storage. The number of coliform bacteria also reduced significantly by UV treatment, and the bactericidal effect was higher when the flow rate is slower. The increase of lightness and yellowness, and decrease of redness were observed after treatment of UV on both vegetable juices, but the differences were not significant between flow rates. The ascorbic acid contents of vegetable juices were reduced by UV irradiation regardless of flow rate, and storage. Overall acceptance in sensory analysis revealed that there was no significant difference between the control and vegetable juice irradiated UV at 0 days, but sample with UV treatment showed higher score at 3 days. Therefore, UV treatment on vegetable juice can elongate the shelf-life without any problems in flavor and color.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.211-217
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• 1997

The physical and chemical stability of anthocyanins from a Korean pigmented rice variety was investigated at various conditions of pH, temperature, metal ion, sugar, organic acid and light. The anthocyanin pigments were relatively stable with half-lives of 36 days (pH 2.0) and 17 days (pH 3.0), while they were decomposed in a day at neutral and basic pH of 7.0 and 9.0 at $25^{\circ}C$. The anthocyanins also showed high thermal stability at pH 3.0; the half-lives were 7.4 hr, 23.6 hr and 96.3 hr at $95^{\circ}C,\;75^{\circ}C\;and\;50^{\circ}$, respectively. Addition of di- and tri-valent metal ions at pH 3.0 resulted in the increase of color intensity and stability throughout 21 days of storage periods at $25^{\circ}C$. Most sugars added accelerated the degradation of anthocyanin pigments, so that fructose showed the greatest degradation effect on the pigments. Addition of citric acid at pH 3.0 increased stability of anthocyanins, while tartaric acid decreased stability. The anthocyanins were very sensitive on light irradiation with a degradation half-life of 14 hr under 20,000 lux-light dosage at pH 3.0.

• Journal of Animal Science and Technology
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• v.50 no.5
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• pp.657-666
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• 2008

This study investigated the effects of dietary probiotics which contained antioxidant astaxanthin on growth performances and meat quality in two pigs farms. A total of 2,400 pigs were gilt and barrow with same number assigned to one of two treatments. The two treatments were control(commercial feed), treatment(probiotics 0.1% feed). Each treatment had 3 replicates. Weight gain, feed intake and feed efficiency were periodically recorded for 90 days. Survival ratio was shown 99.85% in treatment group. Average daily gain was higher in treatment group(0.91kg) than that of control(0.84kg). Back fat thickness was lower in treatment group than that of control, even though the treatment group tended to be higher carcass weight. The treatment group trended higher carcass weight, back fat thickness was lower in treatment group than control. The ratio of carcass grade A was shown higher in treatment than that of control, respectively. Treatment group showed higher value of fat content and water holding capacity. Treatment showed lower value than control in shear force and cooking loss. Hunter value(a and b) of treatment group in meat color was higher than control. Treatment group was lower cholesterol content than control. Control group was shown higher unsaturated fatty acid(stearic acid(C18:0)) value than treatment. Treatment group was shown lower saturated fatty acid(oleic acid(C18:1)) value than that of control. These results suggested that the supplementation of probiotics contained Phaffia rhodozyma could be used effectively for increase productivity of livestock industry.

• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.219-228
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• 2003

Two experiments were conducted to investigate the influence of dietary supplementation of yeast culture on the nutrient digestibility, performance and meat quality in growing-finishing pigs. Corn-soy basal diets contained 20, 18, and 16% CP and 3,265kcal/kg ME at different growth stages. One hundred and twenty pigs(8wk-old) were allocated into four supplementation levels of yest culture (0, 0.1, 0.2, 0.4%) in Expt 1. Weight gain, feed intake and feed efficiency were periodically recorded for 112 days. A metabolic feeding trial was conducted to measure the nutrient digestibility. Physical and chemical characteristics of the Longissimus Dorsi muscle(LM) from the pigs were measured at the end of experiment (Expt 2). In Expt 1, weight gain and feed efficiency were not different among the dietary treatment groups during the overall period. The digestibilities of protein and fiber were greater in 0.1% and 0.2% yeast culture-supplemented groups than in control (P<0.05). However, fat and ash digestibilities were not improved by the dietary treatment. In Expt 2, the LM protein content in 0.1% yeast culture-supplemented group, but not in 0.2% or 0.4%-supplemented group, was greater than that in the control group (P<0.05). The LM pH, purge loss, cooking loss and color were not affected by the dietary treatment. The LM shearing force was less in 0.2% yeast culture-supplemented group than in the control group (P<0.05). Other LM physicochemical properties did not differ between the dietary treatment groups. Total saturated and unsaturated fatty acids percentages and total cholesterol content of the LM did not differ across the dietary treatment groups.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.145-150
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• 2010

This study was conducted to evaluate effects of dietary Agariemycetes on egg quality and fecal noxious gas concentration in laying hens. A total of two hundred forty laying hens were randomly allocated to four treatments with five replicates of twelve chicks per pen. The experiment lasted 42 days with a 7-day adjustment period. Dietary treatments were as follows: 1) CON (basal diet), 2) A1 (basal diet + Agariemycetes 0.1%), 3) A3 (basal diet + Agariemycetes 0.3%) and 4) A5 (basal diet + Agariemycetes 0.5%). There was no significant difference in egg production and egg weight between CON and Agariemycetes treatments. During the second week of the experiment, eggshell breaking strength was higher in A3 and A5 treatments than that in CON treatment (P<0.05). Besides, eggshell breaking strength in P5 treatment was higher when compared with that in CON treatment (P<0.05) in the sixth week. During the second week of the experiment, eggshell thickness was higher in Agariemycetes treatments than CON treatment (P<0.05). Also, A5 treatment was higher than other treatments in the fourth week of the experiment (P<0.05). At the end of the second week, yolk color unit in A5 treatment was lower compared with CON treatment (P<0.05). During the fourth week of the experiment, CON treatment was higher than A3 treatment (P<0.05). During the second week of the experiment, Haugh unit in A3 treatment was greater than that in CON treatment (P<0.05). At the end of six weeks, Haugh unit in CON treatment was lower than other treatments (P<0.05). Fecal ammonia and hydrogen sulfide were increased in Agariemycetes treatments when compared with CON treatment (P<0.05). Compared with CON and A5 treatments, fecal mercaptans was higher than in other treatments in first of the experiment (P<0.05). In conclusion, this study indicated that the addition of Agariemycetes in the diet improved the egg quality and decreased the feacal noxious gas concentration in laying hens.