• Journal of the Korean Wood Science and Technology
• /
• v.44 no.1
• /
• pp.85-95
• /
• 2016

In this study, furfural, which is one of the value-added chemicals, was produced from the hydrolyzate of Quercus mongolica using dilute acid pretreatment, and the optimal pretreatment condition was determined by Response Surface Methodology (RSM) to obtain high yield of furfural. Based on Central Composite Design, the pretreatment experiment was designed with parameters such as reaction temperature ($X_1$), acid concentration ($X_2$), and reaction time ($X_3$) as independent variables, while dependent variable was furfural concentration (Y), and furfural yield (Z) was shown as percentage of Y per a dry weight basis. According to results of RSM, it was confirmed that reaction temperature ($X_1$) was the most influence factor and reaction temperature ($X_1$)-acid concentration ($X_2$) was the most significant interaction factor on furfural yield. Also, the optimal condition for the highest furfural yield was predicted at reaction temperature of $184^{\circ}C$, acid concentration of 1.17%, and reaction time of 5 min by RSM, and expected maximum yield of furfural was 6.37%. Experimentally, the maximum yield of furfural produced at above optimal condition was 6.21%, and it was considerably similar with the predicted value, and therefore the model for furfural production from the hydrolyzate of Quercus mongolica during dilute acid pretreatment could be built using RSM.

• Journal of Animal Environmental Science
• /
• v.10 no.3
• /
• pp.141-154
• /
• 2004

The solar powered water pump is very ideal equipment because solar power is more intensive when the water is more needed in summer and it is very helpful in the rural area, in which the electrical power is not available. The average so]ar radiation energy is 3.488 kWh/($m^2{\cdot}day$) in Korea. In this study, the automatic control logic and system of the water pump driven by the radiation energy were studied, designed, assembled, tested and analyzed for realizing the solar powered water pump. The experimental system was operated automatically and the cycle was continued. The average quantity of the water pumped per cycle was about 5,320 cc. The cycle time was about 4.9 minutes. The thermal efficiency of the system was about $0.030\%$. The pressure level of the n-pentane vapour in flash tank was 150$\%$450 hPa(gauge) which was set by the computer program for the control of the vapour supply. The pressure in the condenser and air tank during cycles was maintained as about 600 hPa and 1,200 hPa respectively. The water could be pumped by the amount of 128kg/($m^2{\cdot}day$) with the efficiency of $0.1\%$ and the pumping head of 10 m for the average solar energy in Korea.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.37 no.4
• /
• pp.86-93
• /
• 2009

This study analyzes the systematic visual images and factors in and outside of the main courtyard in Byungsan-seowon. The results are as follows; In terms of space distribution, Ip-kyo-dang is located at an elevation of 85m and the distance to Byung-san is 365m. Byung-san with the mean gradient over $50^{\circ}$ looked so stiff, and the east side of that cliff is higher than west. In terms of the angle of elevation relationship between Man-dae-ru and Byung-san draw 10.5 degree and it suits with human scale. The D/H ratio of 1:3 makes the given place very spacious but the linear stiff shape of Byung-san may cause the feeling of closeness. The results of the visual image analysis of the main yard facing Byung-san is very positive with a score of 1.70 in openness, 1.78 in wideness, 1.96 in beauty, 1.96 in harmony for the spacious arrangement which overall, makes the seowon beautiful with many open spaces. There are 4 main implicated factors analyzed which are uniqueness, aesthetic, openness and nature. Out of the total variables, these factors' descriptive ability is 55.90% and the remaining 44.10% is error and peculiarities variables. The factor which contributed most to Byungsan-seowon's main yard's visual preference was the 'aesthetic' with B-values of 0.661 and 0.455 in the nature category.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.37 no.4
• /
• pp.32-41
• /
• 2009

Places such as famous urban sights and foreign settlements have recently been created in Korea, which reflects the increase in social and cultural exchanges and the number of place-making and landscape-planning projects. Understanding place identity is required in environmental design and planning. This paper examined the components of the identity of place through comparison of perceptions of "placeness" between residents and visitors of Seo-Rae Village, Seoul, Korea. More than 40% of French nationals in Korea reside in the village, which many Koreans visit as an urban sightseeing place. Twenty-five French inhabitants and forty-one Korean visitors were surveyed. Insideness of Seo-Rae Village was formed by limited activities and needs of the residents, primarily children's education and food purchases. Residents mentioned that the physical environment, especially buildings, lacked theauthenticity of French style. The symbolic meaning of the French village influenced the visitors' activities. The authenticity of French style, however, did not affect the perception of visitors and outsideness of the place. Visitors' activities and cognitive meanings of the place were formed mainly by the commercial environment established by Korean investments. Commercialization of the place and related activities played an important role in establishing insideness of the place. The village shows the phenomenon of the reversal of insideness and outsideness. The "placeness" of Seo-Rae village has been shaped by visitors' tastes rather than the true experience of insideness. Mass identity formed by mass media using French characteristics influenced this phenomenon. Insideness formed by inhabitants appeared to be a pseudo-place, which was created by the French tastes of visitors and lacked French authenticity. Seo-Rae Villagerepresents a superficial cloak.

• Korean Journal of Poultry Science
• /
• v.36 no.1
• /
• pp.39-45
• /
• 2009

This study was carried out to investigate the effect of dietary supplementation of Acanthopanax (A) senticosus and Eucommiaceae on the expression of lipogenic, myogenic and oxidative stress genes in broiler chickens. Birds were subjected (assigned) to one of the following 5 dietary treatments: control (CON), A. senticosus 0.5% (T1), 1.0% (T2), Eucommiaceae 0.5% (T3) and 1% (T4). Each treatment was replicated 8 times with 4 birds per replication, housed in 4 birds per cage. Birds were arranged according to randomized block design. Feeding trial was conducted from day 4 to 35th day of age. Liver and muscle tissues were collected for analysis. Broilers subjected to 1% A. senticosus had higher feed conversion ratio than the other treated birds whereas no significant differences were found in body weight, weight gain and feed intake. The gene expression levels of fatty acid synthase were not different among the treatments while the transcription factor $PPAR{\gamma}$ was highly expressed in Eucommiaceae but not in control and A. senticosus. The gene expression levels of myogenin were high in both A. senticosus and Eucommiaceae compared to control group. MyoD also showed high expression in treated groups furthermore, Eucommiaceae stimulated the expression of MyoD more than that of A. senticosus. The antioxidant gene expressions (SOD, CAT, SOD, GPX) generally were not much different among the treatments, however, SOD and GPX were stimulated in broilers consumed 1% Eucommiaceae diet. The result of this experiment showed that dietary supplementation of A. senticosus and Eucommiaceae in broiler may improve the antioxidant defence system through SOD and GPX without affect of growth performance in broilers.

• Clinical and Experimental Reproductive Medicine
• /
• v.30 no.1
• /
• pp.39-45
• /
• 2003

Objective : To identify the factors affecting the complete fetal loss following multifetal pregnancy reduction (MFPR). Design: Retrospective clinical study. Methods : A total of 256 consecutive treatments of MFPR in IVF-ET cycles performed between 1992 through 2000 in Samsung Cheil hospital were analyzed. MFPR was done around 8 weeks of gestation by transvaginal ultrasono-guided aspiration in multiple pregnancies and reduced to singleton or twins. Stepwise logistic regression was performed to identify the factors affecting the final outcome of pregnancy after MFPR. Dependent variable was complete fetal loss and the independent variables were maternal age, paternal age, initial number of gestational sac (iGSNO), initial number of fetal heart beat, the number of remaining live fetus after MFPR, and chorionicity. Results: The total survival rate was 87.9%, and total fetal loss rate after MFPR was 12.1%. Total fetal loss occurred within four weeks from MFPR procedure was 1.95%. Total loss occurred after four weeks of procedure and before 24 gestational weeks was 8.2%. Seventy nine percent (202/256) of pregnancies delivered after 34 weeks of gestation. The survival rate of pregnancies reduced to singleton was significantly higher than that of pregnancies reduced to twins (93.5% vs. 86.7%, p<0.05). The mean ($\pm$SEM) gestational age at delivery was $36.2{\pm}1.0$ and $34.1{\pm}0.5$ weeks for pregnancies reduced to singletons and twins, respectively (p=0.065). Logistic regression analysis revealed that the maternal age, the number of initial gestational sac (iGSNO), and the number of remaining live fetus after MFPR significantly affected the rate of total fetal loss (Z = 0.174'age + 0.596'iGSNO + 1.324'remaining fetuses -12.07), (p<0.05). Conclusions: MFPR seems to be a relatively safe and efficient method to improve the obstetric outcome in high order multiple pregnancy. Because the maternal age, the number of initial gestational sac and the remaining live fetuses after MFPR affect the total fetal loss rate, restriction of the number of transferred embryos according to the age and MFPR to singleton fetus could be considered for the better obstetric outcome in IVF pregnancy.

• Korean Journal of Health Education and Promotion
• /
• v.24 no.5
• /
• pp.119-135
• /
• 2007

Objectives: The efficacy, feasibility, and safety of bench-step aerobics (BSA) program in overweight or obese Korean adult women have been implied. However, there has been almost no evidence for its psychological benefits. As such, the purpose of this study was to investigate the psychological benefits of BSA program in overweight or obese (body mass index ${\geq}\;23\;kg/m^2$) Korean adult women. Method: Anger, exercise self-efficacy, exercise-related affect, and body image of overweight or obese women who participated in a 12-week BSA program (n=15) were compared with those of their counterparts in the control group (n=13). Subjects were selected among public health center visitors and those recruited by putting an advertisement in local newspapers and the public health center homepage. Data from the exercise and control groups were collected before and after the 12-week BSA program (from August to November in 2006) at the public health centers. The exercise program consisted of 45 to 60 min moderate-intensity (40/50 to 50/60% of their hear rate reserve) BSA performed for 3 days a week. Results: After the BSA program, body image of the subjects in the exercise group was significantly improved and there was a significant difference between the exercise and control groups. Anger, exercise self-efficacy, and exercise-related affect were improved after the BSA program but the changes did not reach the level of statistical significance and there were no significant differences between the exercise and control groups. Conclusions: In conclusion, BSA appears to significantly enhance body image in overweight or obese Korean adult women but its effects on anger, exercise self-efficacy, and exercise-related affect do not appear to be statistically significant. Further studies involving different subjects, particularly whose levels of anger are high or whose levels of exercise-related affect are low to exclude the influence of the ceiling or floor effect, are warranted in a randomized controlled design.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.26 no.3
• /
• pp.159-170
• /
• 2006

This study was conducted to investigate the effects of two dry matter levels of liquid swine manure on dry matter yield and nutritive value of Italian ryegrass, rye and oats, and the chemical characteristics of soil in Jeju. This experiment tested in split plot design. Three forage crops (Italian ryegrass, rye and oats) were the main plot and four fertilizers (no fertilizer=T0, chemical fertilizer=T1, liquid swine manure with DM 2.7%=T2 and liquid swine manure with DM 5.9 %=T3) were the sub plots. Yield and nutrient contents of forage crops and soil properties were determined. Application of liquid swine manure containing 5.9% dry matter resulted in highest DM yield in all three forage crops species compared with the other treatments (p<0.01). Crude protein content(%) and crude protein yield(kg/ha) of forage crops were highest in rye compared with the other forage crops species(p<0.01). K and Mg contents of soil were higher(p<0.01) in rye than in the other species while Na contents was higher(p<0.01) in Italian ryegrass than others. Mg content of soil appeared higher in rye than in the others and higher(p<0.05) in forage crops applied with liquid manure containing 2.7% DM compared with the other species. $NO_3-N$ contents in soil was lower in rye than the other species and higher in species with chemical fertilizer. These findings indicate that most of liquid swine manure produced on local pig farms containing low levels of dry matter and other nutrients suggest a low efficiency of its use as a fertilizer. The liquid swine manure is recommended as a fertilizer for rye production in winter, compared with Italian ryegrass or oat.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.26 no.4
• /
• pp.285-292
• /
• 2006

This study was conducted to evaluate the dry matter yield and forage quality of Kenaf in relation to planting density and growing days in Cheorwon area from 20 May to 12 September in 2005. The experiment was laid out in a split plot design with three replications. The main plots consisted of planting density and growing days with three cultivars of Kenaf as sub-plots; Bowling, Everglade and Tainung. The results obtained were summarized as follows. The dry matter yield increased until 92 days after planting at $10{\times}10cm^2$ planting density, but decreased after the day. The dry matter yield increased with maturity in all three cultivars, especially Dowling showed the highest dry matter yield at each harvest time. The Crude Protein (CP) contents of all three cultivars decreased with maturity. Especially, the decrease in the CP contents was greater in the early stage than in the late stage. The planting density did not affect the CP contents, even though they are little higher in $10{\times}20cm^2$ planting density. The higher CP contents were obseued in Dowling, which is not significant. No difference in the Neutral detergent fiber (NDF) and Acid detergent fiber (ADF) contents was observed in the planting density and cultivar, although the increasing tendency was found with maturity. These results suggest that Kenaf can be a good potential forage crop in the northern area of Korea, especially Dowling showed the great dry matter yield and forage quality when harvested on Day 104 at $10{\times}20cm^2$ planting density.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.26 no.4
• /
• pp.257-266
• /
• 2006

Studies were carried out to evaluate the effect of liquid pig manure on the production of Japanese millet, the chemical characteristics of pasture soil and leaching water. The study was undertaken from June to September 2005. Randomized complete block design was used to allot four treatments: T1 (no fertilizer), T2 (N : 200 kg/ha, p : 150 kg/ha, K : 150 kg/ha), T3 (liquid pig manure containing 1.7% DM 200 kg N/ha) and T4 (liquid pig manure containing 7.0% DM 200 kg N/ha). Leaching water was sampled at 21 August (1st time), 9 September (2nd time) and 26 September (3rd time), 2005, respectively. No significant differences in the dry matter yield of Japanese millet was found among the four treatments, whereas the plant lengths of Japanese millet were higher in the T2, T3 and T4 than in T1 (p<0.05). Nitrogen, P and K uptake of J. millet tended to be influenced by application of chemical fertilizer or 7.0% DM liquid pig manure compared with T1 or 1.8% DM liquid pig manure. The organic matter (OM) content of soil was higher in T2, T3 and T4 than in T1. Na content was highest in T3 among the four treatments. $NO_{3^-}N\;or\;NH_{4^-}N$ content in leaching was not different among the four treatments. $SO_4$ content in leaching water sampled in 1st time was high in T4, but in T3 from 3rd time (p<0.05). Cl, Mg and Na contents were high in leaching water sampled in the 1st time from T4, whereas high in those from T3 in 2nd or 3rd time. Results show that the application of a high DM liquid pig manure is not better for producing Japanese millet and improving the properties of pasture soil than a low DM liquid pig manure. However, the contents of $SO_4$, Cl, Mg and Na in leaching water sampled in 1st time were high in a high DM liquid pig manure.