• Journal of Animal Science and Technology
• /
• v.53 no.5
• /
• pp.409-418
• /
• 2011

This study was conducted to investigate the effects of dietary probiotics and immunomodulator on growth performance, carcass characteristics, fecal $NH_3$ content and pathogenic bacteria counts in ileum and cecum and ileum of broiler chicken (Korean native chicken, HanHyup No. 3). A total of 120 (day-old) chicks were randomly divided into 5 treatments with 3 replicates and there were 8 birds per replicate. Dietary treatments consisted of five diets; the corn-soybean based control diet (C), the diet containing antibiotics (Avilamycin) 10 ppm (T1), the diet containing probiotics 1 [(Lactobacillus ($4.45{\times}10^6$) + yeast ($1.51{\times}10^6$) + Bacillus subtilis ($3.50{\times}10^5$)] at 0.5% level (T2), probiotics 2 [(Lactobacillus ($6.70{\times}10^7$) + yeast ($3.10{\times}10^6$)] at 0.5% level in diet (T3), and the diet containing probiotics 3 [T2 + ${\beta}$-glucan + organic acid] (T4) and raised for 9 weeks. There were no significant differences among treatments in weight gain, feed intake and feed conversion. Carcass ratios of broilers were higher in T3 and T4 than other treatments, however, the differences were non-significant. Internal organs and liver, heart weight were significantly increased in T4 (p<0.05) compared to other treatments. The fecal $NH_3$ gas content was decreased (p<0.05) in antibiotics fed group than others. However, probiotic fed groups were not different when compared with control. The number of Salmonella and E. coli in cecum were reduced in the group supplemented with probiotics and immunomodulator compared to the antibiotics (p<0.05). In this experiment, we showed that diets containing pro-biotics and immunomodulator were capable of an alternative to antibiotics.

• Journal of Digital Convergence
• /
• v.16 no.5
• /
• pp.463-468
• /
• 2018

The purpose of the study was to investigate the gender differences of anaerobic capabilities between anaerobic capacity(AC) from Wingate test and anaerobic work capacity(AWC) from critical power test in untrained male and female adults. Both tests were carried out to 12 male and 13 female subjects on a Monark cycle ergometer. The results of this study demonstrated that men were higher than women in AC for the Wingate test, but no gender difference(J/kg) in AWC for the Critical Power test. There was a significant relationship between AC(J/kg) and AWC(J/kg) in women(r=0.61, p<0.05), but no significant relationship in men(r=-0.32, p>0.05). ANCOVA analyses using $VO_{2max}$ and body weight as covariates had significant influence on the AWC gender difference. The study provides preliminary data on gender differences of anaerobic capabilities.

• Journal of Environmental Science International
• /
• v.22 no.12
• /
• pp.1633-1641
• /
• 2013

The objective of this study was to analyze correlation between phenological characteristics of Salix spp. and meteorological factors in the Upo wetlands. Phenology of Salix subfragilis Andersson and Salix chaenomeloides Kimura was monitored from 2007 to 2012. Meteorological variables were monitored by Korea Meteorological Administration (Hap-chon). Average date of flowering, fruiting, seed dispersion was 86, 113, 136 days for S. subfragilis and 112, 140, 164 days for S. chaenomeloides as Julian days. Flowering of S. subfragilis and S. chaenomeloides were correlated with daily mean air temp. in March (r=-0.92, r=-0.85, p<0.05). Fruiting of S. subfragilis was correlated with total precipitation between Jan and March of previous year (r=-0.90, p<0.01), however, the fruiting of S. chaenomeloides was highly correlated with max. temp. in Jan of previous year (r=0.99, p<0.01). Seed dispersion of both species is correlated with min. temp. in Feb. Phenology monitoring will contribute to understanding Salix spp. response against climate change.

• Journal of the Korean Applied Science and Technology
• /
• v.28 no.4
• /
• pp.508-516
• /
• 2011

Hydrotreated biodiesel(HBD) is paraffinic bio-based liquid, with the chemical structure $C_nH_{2n+2}$, originating from vegetable oil(the process can also be applied to animal fat). The oil or fat is treated in a number of process, the most important being hydrogenation, in order to create a bio-based liquid diesel fuel. During the hydrogenation, oxygen is removed from the triglyceride and converted into water. Propane is formed as a by product and can be combusted and used for energy production. HBD can be used in conventional diesel engines, pure or blended with conventional diesel, due to its similar physical properties to diesel. This study reports the quality characteristics with chemical and physical properties as an alternative diesel fuel. Especially, HBD showed higher cetane value and number than FAME, and it is consisted of $C_{15}$ - $C_{18}$ n-paraffinic compounds. We also describes quality characteristics of HBD blends(2, 5, 10, 20, 30, 40, 50 vol%) in automotive diesel. HBD blends(max. 20 vol%) were the limit by the Korean specification due to poor low temperature characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2008.11a
• /
• pp.209-209
• /
• 2008

$BaTiO_3$는 대표적인 강유전체 재료로서 적층형 세라믹 콘덴서 (MLCC), PTC thermistor, resonator 등 다양한 분야에서 사용되고 있다. $BaTiO_3$ 기본조성으로 하는 PTC 써미스터는 온도가 올라감에 따라 저황이 높아지는 특성을 가지고 있으며, 이러한 PTCR 특성은 작동되는 큐리온도에 따라 그 적용이 달라진다. PTCR 소자는 소결온도, 소결분위기, 불순물, 첨가제 등의 제조공정상의 인자들과 기공률, 결정립 크기 등이 복합적으로 작용해 PTCR 특성에 영향을 미치기 때문에 제조하기에 무척 까다로운 소자로 알려져 있다. 하지만 우수한 특성을 지닌 PTCR 소자를 제조하기 위하여 새로운 조성개발이 이루어지고 있으며, 전기적 특성 개선, 재현성 확보, 제조원가 절감 등의 측면에서 새로운 공정개발이 이루어지고 있다. 본 연구에서는 Sm을 첨가한 $BaTiO_3$계 재료의 PTCR 특성에 미치는 Ti/Ba ratio 등의 변화에 따른 영향을 조사하고 공기 중과 환원분위기 중에서 소결된 시편의 차이점과 재산화 처리에 따른 PTC 특성에 미치는 영향을 R-T 측정으로 고찰하였다. 본 조성은 환원 분위기에서 소결할 경우 그 미세구조는 Ti/Ba ratio비가 높을 때 grain size가 커져 상온 비저항을 낮출 수 있었다. Sm 첨가로 상온 비저항값은 낮출 수 있었으나 공기 중에서 재산화 처리하더라도 jumping ratio$(R_{max}/R_{25^{\circ}C})$는 Ti/Ba ratio와 거의 무관한 것으로 분석되었다.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.135-136
• /
• 2012

Carbon atoms near the surface of W(110) induce reconstructions such as $R(15{\times}12)$ -C/W(110) which consists of two characteristic parts, one square shaped and bright protrusion and two smaller ones. In the atomic resolution STM image, the bigger protrusion shows the periodicities of clean W(110), indicating that it is almost carbon poor region. The smaller protrusion contains hexagonal carbide surface layer of ${\alpha}$-W2C on W(110). Employing this carburized W(110) as templates, we grow Co and Fe clusters of less than ten atoms. Due to the selectivity of bonding sites, growth of larger cluster is highly unfavorable for Co and the size of clusters is very uniform. Since Co atoms prefer to sit on the bigger protrusion rather than smaller one, Co cluster can be arranged one-dimensionally in $R(15{\times}12)$-C/W(110) with quite uniform size distribution. However, Fe clusters sit on both sites without favored site, but still with uniform size distribution. On the other hand, Fe clusters can be grown with quasi one-dimensional order in $R(15{\times}3)$-C/W(110), which consists of only smaller protrusions. We investigate the magnetic properties of the ordered nano-sized clusters. Experiments using XMCD reveals little magnetic moment of Co cluster on $R(15{\times}12)$-C/W(110). This observation is consistent with the predictions of our first principles calculations that small Co clusters can be nonmagnetic or antiferromagnetic with low mean magnetic moment per atom.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.37 no.1
• /
• pp.17-26
• /
• 2013

Market available fermented indigo powders of Indian origin (FI1, FI2), Chinese origin (FC1, FC2), and raw indigo powders of Indian origin (R1, R2) were examined using TLC and HPLC analyses to investigate their pigment contents. TLC analysis gave $R_f$ values of 0.81 and 0.72 for blue and red pigments, respectively. All the powder products and the synthetic and natural indigo standards eluted at 6.9 min and 8.3 min in the HPLC chromatograms, and the peaks showed the ${\lambda}_{max}$ at 610nm and 542nm, representing indigotin and indirubin, respectively. The pigment content calculated based on the area of indigotin and indirubin peaks in the HPLC chromatograms showed that the indigotin content was higher in FC1 and FC2, while FI1 and FI2 had a higher indirubin content. The relative percentage of indirubin was the highest in R2, but the HPLC peak intensity was quite low. Despite the higher indigotin content in FC1 and FC2, cotton dyed with FI1 and FI2 (versus cotton dyed with FC1 and FC2) showed a higher blue (B) hue, the highest K/S values, and the highest antimicrobial effect.

• Journal of the East Asian Society of Dietary Life
• /
• v.15 no.6
• /
• pp.675-686
• /
• 2005

It is known that appropriate exercise changes body composition and improves coronary artery disease. This study was undertaken to evaluate the relationships between aerobic exercise, body composition, and the blood lipid levels in the middle-aged women(33 to 54 years old). The 57 subjects were divided into two groups based on their exercise: the aerobic exercise group(A group: 44) which performed at about $60\%$ of $VO_2max$ during over 6 months and the sedentary one(S group: 13). The percentages of body fat waist/hip ratio(WHR), body mass, and lean body mass of two groups were measured and compared in serum HDLC level and oxidized LDL level, the two most effective factors of coronary artery disease. The subjects in A group showed the lower percentages of body fat and WHR, when compared with the ones in S group. The body mass and lean body mass of A group subjects were higher than those of S group subjects. The serum HDL-C level$(58.6\pm12.7mg/mL)$ was significantly higher for A than S group subjects.(p<0.05) The sem ox-LDL level $(6.64\pm4.11Eu/mL)$ for A group subjects was lower than S group ones. The fat mass showed significantly positive correlations with atherogenic index(AI)(r=0.301, p<0.05), and with blood glucose levels(r=0.334, p<0.05). Also the WHR whowed significantly positive correlations with LDL-C levels(r=0.277, p<0.05), and with AI(r=0.466, p<0.01). In summary, the subjects in A group have the lower percentages of body fat and WHR, when compared with the ones in S group. Also, A group subject showed a tendency that exercise enhances serum HDL-C levels and decreases oxidized LDL levels. And aerobic exercise showed positive results which change body composition and improve blood lipid levels. There were significantly positive correlations among the percentages of body fat At and blood glucose level. These results suggest that moderately intensive exercise is a significant factor in reducing coronary artery disease.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.27 no.8
• /
• pp.541-546
• /
• 2014

Korea Expressway Corporation established standard of LED lighting fixture in Dec. 2013. To raise compatibility, the standard requires a fixed form and it is applied to street lights and tunnel lights, etc. Because streetlight has different circumstance condition from tunnel light that is down light and exposed to constant wind velocity over height of 8 meters, in case of LED module which has the same shape, characteristic of radiant heat can be different. In this paper, we designed 25 [W] LED Module that is designated by standard of Korea Expressway Corporation and analyzed characteristics of radiant heat about natural convection and forced convection. It is dropped 10.12[$^{\circ}C$] that max temperature is decreased by increasing 20 mm of bended height of heatsink at the condition of natural convection. Radiant heat characteristic of bended height 35 mm became 78.08[$^{\circ}C$] at the condition of natural convection, 55.30[$^{\circ}C$] at the condition of forced convection so that 22.78[$^{\circ}C$] is decreased that is 29.1[%] decrease. Bended height 55mm became 67.96[$^{\circ}C$] at the condition of natural convection, 48.04[$^{\circ}C$] at the condition of forced convection so that 19.92[$^{\circ}C$] is decreased that is 29.3% decrease.

• International Journal of Highway Engineering
• /
• v.12 no.4
• /
• pp.147-155
• /
• 2010

A prediction model of resilient modulus($E_R$) was developed for recycled crushed-rock-soil mixtures. The evaluation of $E_R$, using the "orthodox" repeated loading tri-axial test, is not feasible for such a large-size gravelly material. An alternative method was proposed hereby using the subtle different modulus called nonlinear dynamic modulus. The prediction model was developed by utilizing in-situ measured shear modulus($G_{max}$) and its reduction curves of modeled materials using the large free-free resonant column test. A pilot evaluation of the model parameters was carried out for recycled crushed-rock-soil-mixture at a highway construction site near Gimcheon, Korea. The values of the model parameters($A_E,\;n_E,\;{\varepsilon}_r\;and\;{\alpha}$) were proposed as 9618, 0.47, 0.0135, and 0.8, respectively.