• Journal of Korean Society of Forest Science
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• v.9 no.1
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• pp.55-60
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• 1969

In order to understand the growth percentage of red pine, author had 207 trees cut and made stem analysis on them and there by studied and analysed volume growth percentage, bark volume percentage, diameter growth percentage and the relation between diameter growth percentage and volume growth percentage and so forth. The result was as follows. 1. The volume growth percentage decreased as the age class increased and it was about 3% at the cutting age. 2. Bark volume percentage was about 5~15% and it seemed to be about constant irrespective of the age class. 3. The diameter growth percentage gradually decreased as the age class increased and it would be constant from a certain age class on. 4. As for the relation between the diameter growth percentage and volume growth percentage, the correlation ratio showed to increase with the age class increase generally the value of b was between 2.0~3.6.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.1-6
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• 2015

Recently, lots of researches on concrete with high volume mineral admixture such as ground granulated blast furnace slag (GGBFS) have been carried out to reduce $CO_2$. It is known that the precast concrete has an advantage of high strength at early age due to steam curing, even if concrete has high replacement level of mineral admixture. However it demands the investigation of compressive strength properties according to steam curing regimens. In this study, concretes with water-binder ratio of 32, 35% and water content of 135, 150, $165kg/m^3$ were produced to investigate compressive strength properties of high volume (60% by mass) GGBFS cement concrete according to steam curing regimens. Then steam curing was implemented with the maximum temperature of 50, $60^{\circ}C$ and steaming time of 5, 6, 7 hours. From the test results, it was found that steam curing was effective to raise early strength of high volume GGBFS cement concrete, but 28 day compressive strengths of steam cured specimens were lower than those of water cured specimens. Thus, a further study would be needed for the optimum steam curing regimens to satisfy target demolded strength and specified strength for the application of high volume GGBFS cement concrete to precast concrete members.

• Culinary science and hospitality research
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• v.20 no.6
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• pp.80-90
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• 2014

This study was conducted to investigate the effects of bitter melon (Momordica charantia L.) powder on the quality characteristics. The bulk density of cookie dough of the test groups containing bitter melon powder did not show any significant difference compared to the control group. The pH of cookie dough and cookies decreased with the addition of bitter melon powder. The moisture content of the groups containing bitter melon powder was higher than that of the control group. The spread ratio of the groups containing bitter melon powder was higher but the loss rate of cookies was lower than those of the control group. In color, the L value was decreased significantly by addition of bitter melon powder, but the a and b values did not show any significant differences compared to the control group. The hardness of the test groups containing bitter melon powder was lower than that of the control group. For DPPH radical scavenging activity, the control group measured 20.69%, whereas the test groups containing bitter melon powder ranged from 38.37~69.48%. Sensory evaluation scores in terms of appearance, flavor, taste, texture and overall preference of the group containing 3% of bitter melon powder did not show any significant differences compared to the control group.

• Food Science of Animal Resources
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• v.37 no.3
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• pp.360-367
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• 2017

This study was conducted to investigate the effect of duck skin on cooking loss, emulsion stability, pH, color, protein solubility, texture profile analysis (TPA), apparent viscosity, and sensory characteristics of press type duck ham with different ratio of duck breast meat and duck skin. Five duck ham formulations were produced with the following compositions: T1 (duck breast 70% + duck skin 30%), T2 (duck breast 60% + duck skin 40%), T3 (duck breast 50% + duck skin 50%), T4 (duck breast 40% + duck skin 60%), and T5 (duck breast 30% + duck skin 70%). The cooking loss and fat separation were lower in T1, and the total expressible fluid separations were lower in T1 and T2 than others. The pH ranged from 6.48 to 6.59, with the highest values in T4 and T5. T5 had the highest CIE $L^*$-value, and T1 and T2 had the highest CIE $a^*$-values; however, CIE $b^*$-values did not differ significantly between the duck ham samples. The protein solubility and TPA (hardness, springiness, cohesiveness, gumminess, and chewiness) were the highest in T1. T1 and T2 had higher scores for color, tenderness, and overall acceptability. T1, T2, and T3 showed significantly higher values, but there were no significant differences for flavor and juiciness. Regarding apparent viscosity properties, T1 and T2 had higher viscosity values than the other formulations. In conclusion, the T1 (duck breast 70% + duck skin 30%) and T2 (duck breast 60% + duck skin 40%) duck hams show the highest quality characteristics.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.5
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• pp.463-470
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• 1995

An experiment was conducted to evaluate the effects of chromium picolinate on growth performance, nutrient utilizability, carcass composition, serum traits and in vitro protein synthesis of 3 day old Arbor Acres broiler chickens when dietary crude protein levels were varying in diets. Six replicates of eight chicks each (average initial weitht = 59.4 g) were randomly assigned to three levels (low, medium, high) of dietary crude protein at two levels of chromium (0, 200 ppb Cr/kg diet) as chromium picolinate. Six chicks/treatment were randomly chosen for analyses of carcass composition, six additional chicks/treatment were randomly chosen for analyses of serum components, and a chick/treatment was chosen for in vitro culture of liver tissue. Chromium picolinate did not affect feed intake, protein and fat utilizability, regradless of dietary crude protein level. But feed/gain ratio were more improved in groups fed the low protein diets added with chromium picolinate compared with groups fed the medium and high protein diets with chromium picolinate. Carcass fat tended to decrease whereas carcass protein tended to increase when added with chromium picolinate. Broilers fed diets with chromium picolinate exhibited lower serum triglyceride and nonesterified fatty acid concentrations than those fed without chromium picolinate (p < 0.05). Both secreted and retained proteins in cultured acinar cell were higher in groups fed diets with chromium picolinate than those fed diets without chromium picolinate (p < 0.05). It could be suggested that chromium picolinate was effective in improving weight gain and nutrient utilizability when dietary crude protein was low (p < 0.05), and also effective in manipulating carcass fat when dietary crude protein level was high (p < 0.05).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.1 no.1
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• pp.3-25
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• 1963

Experiments were carried out to classify the ecotypes and maturity groups of soybean varieties, and to make clear the relationships among these ecotypes, maturity groups and some characteristics in the growing and ripening process of soybean varieties in Korea. Soybean varieties used as the material were 138, 57 varieties collected from Japan, America and Canada and 81 local varieties of Korea. These varieties were grown in the Experimental Farms, College of Agriculture, Seoul National University, Suwon, Korea and Chinju Agricultural College, Kyungsang Namdo, Korea. Seed sowing was conducted at 8 times from April15 to July 29, at 15 day-intervals, in 1962. The classification methods of ecotypes and maturity groups applied in this study, and the results obtained are summarized as follows; 1. Ecotypes were classified from the standpoint of the periods from emergence to flowering, the shortened ratio of days from sowing to flowering by delayed sowing, and the periods from flowering to maturity(as shown in Table A). 2. All varieties wer classified into 10 ecotypes of Ia$_1$, Ib$_1$, IIa$_2$, IIb$_1$, IIb$_2$, IIIb$_1$IIIb$_2$, IIIc$_1$and IIIc$_2$ symbols. Korean local varieties, however, belong to 6 ecotypes of IIb$_1$, IIb$_2$, IIIb$_1$, IIIc$_2$, IIIc$_1$ and IIIc$_2$, respectively(table 1). 3. Durations from sowing to maturity were from 120 to 190 days in April sowing plots of all varieties. From the standpoint of the durations, maturity groups were classified into 9 groups from group I, extreme early, to group IX, extreme late, but our local varieties belong to 5 maturity groups of III, IV, V, VI and VII symbols, respectively(Table 2). 4. Kinds of ecotypes and maturity groups, and the number of soybean varieties belonging to those are as shown in Table B. 5. In this study, it was observed that there were some close relations between these ecotypes and maturity groups (Table 3,4), and among the ecotypes, maturity groups and some other characteristics in the growing and ripening process of the soybean varieties(Table 5). 6. Furthermore, it was also observed that the kinds of ecotypes and maturity groups of recommended varieties in the southern Korean provinces are more numerous than those of the northern provinces in Korea.

• Korean Journal of Poultry Science
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• v.34 no.2
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• pp.137-141
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• 2007

This experiment was conducted to investigate the effects of dietary yeast (Saccharomyces exguus) supplementation on growth performance, cecal microflora and fecal ammonia gas in broiler chicks. A total of two hundred seventy, 1-d-old male broiler chicks (Ross strain) were randomly allotted to nine pens (replicates), 30 birds per pen. There were three dietary treatments with three replicates. The treatments were control (virginiamycin 0.05%+salinomycin 0.03%), Saccharomyces exguus 0.5 and 1.0%. Total body weight gain were significantly higher in Saccharomyces exguus1 1.0% treatment than the control (P<0.05). Although not significant, the yeast supplementation tended to improve the feed conversion ratio. No significant differences were observed on the numbers of cecal E. coli, Salmonella and Lactobacillus in yeast treatments compared to those of control. The production of fecal ammonia gas was significantly lower in yeast treatments than the control (P<0.05). The concentrations of fecal short chain fatty acids and volatile organic compounds were not different among the groups. These results suggest the possibility that yeast (Saccharomyces exguus) could be used as the alternative of antibiotic growth promoters by improving the performance of broiler chicks. In addition, dietary yeast could improve the environment of broiler houses by reducing fecal ammonia production.

• The Korean Journal of Food And Nutrition
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• v.18 no.2
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• pp.103-108
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• 2005

This study was carried out to investigate the acceptable ratio of sulgidduk with tapioca flour. The moisture content, color difference and volume of sulgidduk with tapioca flour were measured. Texture and sensory evaluation of sulgidduk with tapioca flour were taken. The moisture content of tapioca sulgidduk showed significant difference between the added tapioca flour and control. The lightness(L) decreased significantly as concentration of tapioca flour increased. Whereas the redness(a) and yellowness(b) were increased significantly when the amount of tapioca flour was increased. The volume was decreased significantly according to increase of tapioca flour concentration. The hardness, gumminess and chewiness were increased significantly when the amount of tapioca flour was increased. In the result of sensory evaluation, tapioca sulgidduk with the addition of $10\%$ tapioca flour was the most preferred with regard color, flavor, chewiness and overall preference. These results indicated that tapioca sulgidduk with the addition of $10\%$ tapioca flour has the best quality.

• The Korean Journal of Food And Nutrition
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• v.25 no.1
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• pp.83-89
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• 2012

In this study red ginseng was extracted with ethanol and then fermented by yeasts including Lactobacillus casei and Bifidobacterium longum. Fermented red ginseng extracts(FRGE) were found to be more effective antioxidants in vitro with regards to 1,1-diphenyl-2-picrylhydrazyl(DPPH) radical scavenging activity than red ginseng extracts(RGE). In FRGE, the contents of ginsenosides $Rb_1$, $-Rb_2$ and -Rc were much lower than in RGE, however, the contents of ginsenosides 20(S)$-Rg_3$, 20(R)$-Rg_3$ and compound K were higher than RGE. FRGE was added to Yanggaeng(0, 5, 10, 15, 20%), and physicochemical and sensory evaluations of the Yanggaeng were conducted. The L and b values of Yanggaeng with added FRGE were decreased by increasing the ratio of FRGE, while the a value was increased. Sensory evaluations for, taste, color, flavor, texture and overall acceptability of Yanggaeng with addition of FRGE (10%) were applicable for improving the Yanggaeng product.

• Journal of the Korean Ceramic Society
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• v.50 no.3
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• pp.206-211
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• 2013

The effect of a $WO_3$ or $Ga_2O_3$ addition on the densification, phase evolution, optical reflectance, and elastic and dielectric properties of $Y_2O_3$-doped AlN ceramics sintered at $1800^{\circ}C$ for 3 h is investigated. The investigated compositions of the additives are 4.5 wt% $Y_2O_3$ (YA), 3.5 wt% $Y_2O_3$-1.0 wt% $Ga_2O_3$ (YGA), and 3.5 wt% $Y_2O_3$-1.0 wt% $WO_3$ (YWA). $YAlO_3$ and $Y_4Al_2O_9$ form as the secondary phases in all of the investigated compositions, whereas $W_2B$ appears additionally in the YWA. In the YGA, Ga is detected in the AlN grains, indicating that the dissolution of $Ga_2O_3$ into the AlN lattice occurs. The addition of $WO_3$ blackens the specimen more significantly than that of $Ga_2O_3$ does. In all of the investigated specimens, the linear shrinkage and the apparent density are above 20 percent and in the range of 3.34-3.37 $g/cm^3$, respectively. The elastic modulus, Poisson's ratio, the dielectric constant, and the dielectric loss are in the ranges of 335-368 GPa, 0.146-0.237, 8.60-8.63, $2.65-3.95{\times}10^{-3}$, respectively. The sinterability and the properties of $Y_2O_3$-doped AlN ceramics are not much altered by the addition of $WO_3$ or $Ga_2O_3$.