• Journal of Animal Science and Technology
• /
• v.51 no.3
• /
• pp.241-248
• /
• 2009

Metabolic trial with 3 fistulated sheep was conducted in a 3 $\times$ 3 Latin square design and feeding trial with 24 Hanwoo steers in 12 month of age for 20 months was conducted to investigate the replacing effect of rice straw with fermented spent mushroom (Flammuliua velutipes) compost (FSMC) on fermentation characteristics, ruminal effective degradabilty and whole tract digestibility of nutrients in sheep, and to examine the growth performance of Hanwoo steers. Experimental diets for the metabolic trial with sheep were commercial concentrates and rice straw in the ratio of 70 : 30 (CON, DM basis). Same concentrate with 30% FSMC and 70% rice straw (FSMC-30) and 60% FSMC and 40% rice straw(FSMC-60). Diets for Hanwoo steers in three treatments were same as for metabolic trial in replacing ratio of rice straw with FSMC. pH of rumen fluid in sheep was not affected by FSMC. Ammonia-N content in the rumen fluid was highest in the sheep fed FSMC-60 at 3h (P<0.045). The CON diet increased (P<0.001) acetate proportion at 1h and 3h post feeding compared to FSMC-60 diet while propionate proportion was highest in the sheep fed FSMC-60 diet for all the sampling times (P<0.027~P<0.002). Increased proportion of butyrate was observed at 30 min prior to feeding (P<0.031), and 1h (P<0.011) and 6h(P<0.039) post feeding from sheep fed FSMC-30 diet compared to those from sheep fed other diets. Effective degradability in the rumen was not influenced by experimental diets. Whole tract digestibility of crude protein (P<0.031) and neutral detergent fiber (P<0.006) tended to be increased in the sheep fed CON diet while corresponding values were lowest in the sheep fed FSMC-60 diet. Total body weight gain of Hanwoo steers for 8 months was not different among diets, thus daily body gain was not influenced by the experimental diets.

• Journal of the Korea Concrete Institute
• /
• v.13 no.6
• /
• pp.544-552
• /
• 2001

Korea is classified into low and moderate seismic zone from the view-point of seismic hazard level. Korean seismic provisions has been developed based on UBC and ATC 3-06. Thus, in calculation of design base shear according to Korean provisions response modification factor (R) is included in the formula of design base shear. The major role of this factor is to reduce the elastic design base shear whereby structures can behave in inelastic range during design level earthquake ground motions(mean return period of 475 yrs.). R factor is assigned according to material and structural systems. In this study, R factor for bearing wall system is considered. Most of the walls of apartment buildings in Korea resist gravity and seismic loads simultaneously so that this wall system can be classified into bearing wall system. Structural details of these walls are different from those used in Japan and U.S.. They are all rectangular in sectional shape rather than barbell in shape, and also have special lateral reinforcement details at the boundaries of a wall. In Korean seismic design provisions(1988), two different values(3.0 and 3.5) of R factor are assigned to the bearing wall systems according to the wall details. However, in updated seismic provisions(2000), only one value is assigned to R factor(3.0) irrespective of wall details. In this study, the design base shear values in Korean seismic design provisions(1988, 2000), ATC 3-06, UBC are compared. Also experimental study was carried out to evaluate the seismic performance of structural walls. For this purpose, five test specimens were made which have special details used in apartment bearing wall systems in Korea. Based on the results of this study, response modification factor for bearing wall system is discussed.

• Korean Journal of Organic Agriculture
• /
• v.17 no.3
• /
• pp.347-356
• /
• 2009

In attempt to select the most appropriate forage legume species, this study was conducted on the 10 forage legume crops suitable for the central region of Korea and investigated their productivity, feed values and stock carrying capacity. In the results, red clover showed fresh matter yield 38.6 ton/ha, dry matter yield 7.8 ton/ha, crude protein yield 1.0 ton/ha, total digestible nutrients(TDN) yield 4.6 ton/ha, its fresh matter yield, dry matter yield and nutrient yield were significantly(p<0.05) higher than other species. The value of neutral detergent fiber(NDF) and acid detergent fiber(ADF) were getting higher by the late harvest time then galega and cicer milkvetch were the highest and yellow suckling clover was the lowest value. Relative feed value(RFV) showed good feed values above 100 except cicer milkvetch and galega. In terms of feed grading, yellow suckling clover, yellow blossom sweet clover, crimson clover, hairy vetch were classified into 1st grade, above 151%. The average stock carrying capacity was yet high Kcp(2.18 head/ha/yr), KTDN(1.25 head/ha/yr) and K(0.04 head/ha/yr). Especially, red clover had the highest stock carrying capacity, Kcp 6.84 head/ha/yr, KTDN 3.64 head/ha/yr and K 0.05 head/ha/yr. According to results, red clover is considered to be the most appropriate crops for the central region, in terms of quality, feed value and stock carrying capacity.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2017.05a
• /
• pp.559-562
• /
• 2017

In city, tracing of power transmission lines is difficult due to compound installation of overhead and underground lines, transposition, bad view caused by trees or big buildings. It is hard problem for electrical technician on site to trace power transformers or power lines to serve customers in 3 phase -4 wires power distribution systems. It is necessary that the correct and fast tracing method is required for load balancing among distribution lines. Old technology use to trace off-lines with high power impulse injection. Our proposed method use to trace live lines with very small power high frequency signal injection. Typical power transformers in the distribution system prevent propagating the higher frequency carrier signal. The proposed method uses the limited propagation ability to identify the power transformer to serve customers. Two end communication terminals are required to be synchronized between them for determination on electrically same phases. Challenging issue is to achieve synchronization without GPS providing synchronizing time. A novel power transformer and wire identification system is designed and implemented. The system consists of a transmitter and a receiver with power-line communication module. Some experiments are conducted to verify the theoretical concepts in a big commercial building. Also some simulations are done to help and understand the concepts by using MATLAB Simulink simulator.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.05a
• /
• pp.505-508
• /
• 2016

In city, tracing of power transmission lines is difficult due to compound installation of overhead and underground lines, transposition, bad view caused by trees or big buildings. It is hard problem for electrical technician on site to trace power transformers or power lines to serve customers in 3 phase -4 wires power distribution systems. It is necessary that the correct and fast tracing method is required for load balancing among distribution lines. Old technology use to trace lines with high power impulse injection. Our proposed method uses to trace lines with very small power high frequency signal injection. Simulation models for 3-phase power transformers, 3-phase wire lines, and customer loads are described to investigate the transmission characteristics of high frequency power line carrier. Distribution lines have only a limited ability to carry higher frequencies. Typically power transformers in the distribution system prevent propagating the higher frequency carrier signal. The proposed method uses the limited propagation ability to identify the power transformer to serve customers. The system consists of a transmitter and a receiver with power-line communication module. Some experiments are conducted to verify the theoretical concepts in a big commercial building. Also some simulations are done to help and understand the concepts by using MATLAB Simulink simulator.

• Journal of Bio-Environment Control
• /
• v.12 no.1
• /
• pp.7-11
• /
• 2003

Cellular glass foam (CGF), the reprocessed glass, has a possibility to be used as a medium component in plug culture of horticultural crops due to the its excellent air and water permeability as comparable to perlite. An experiment was conducted to investigate growth of plug seedlings of Lycopersicum esculentum 'Segye' as influenced by irrigation frequency in various medium combinations of CGF (2.0-4.0 mm particle size) and peatmoss. Seeds were sown in 200-cell plug trays, filled with mixtures of CGF and peatmoss either at 33：67 or 25：75 (％. v/v) and were germinated on a fogged propagation bed. The irrigation frequencies used were one, two or three times per every two days. A commercial plug medium (Tosilee medium) was used as the control, and the irrigation frequency in the control was one time per day. Growth of seedlings, and medium pH and EC were measured at 33 days after sowing. The medium composition had little influence on overall growth of seedlings. Irrigation frequency very significant affected number of leaves, leaf area, chlorophyll concentration, fresh and dry weights of shoots and roots, and dry matter. Growth of seedlings was the greatest with the highest irrigation frequency in the 25% CGF＋75% peatmoss mixture.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.21 no.1
• /
• pp.7-14
• /
• 2001

This pot experiments was conducted to find out the forage productivity and quality in a grass/clover sward as affected by the application of three different fertilizers; double superphosphate(DS), fused Mg-phosphate(FP), and complex fertilizer(CF) on newly reclaimed hilly soil. This 2nd part was concerned with the contents and yields of mineral nutrients and general components. The results obtained are summarized as follows: 1. The concentrations of P, Ca. Mg, and Na by the forage species were relatively higher in the CF plots than in the FP and DS plots. The yields of mineral nutrients by the forage species were high in the order: CF>FP>DS plots. Especially. these were higher in the ladino clover and mixed forages than in orchardgrass. 2 The contents of crude protein and crude ash were highest with the CF plots, compared with the FP and DS plots. The yields of general components in the ladino clover and mixed forages were apparently highest with the CF plots. whereas these in orchardgrass not showed consistent differences among the plots. It was recognized that the positive effects on the concentrations and yields of mineral nutrients and general components in forages were higher in the order: CF＞FP＞DS plots.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.39 no.1
• /
• pp.1-8
• /
• 2019

This study was conducted to predict the energy requirements for maintenance and growth of female Korean black goats during their growth and pregnancy phases. Fifty female goats ($18.7{\pm}0.27kg$) in their growth phase with an average age of 5 months were stratified by weight and randomly assigned into 5 groups. They were fed 5 diets varying in metabolic energy (ME) [2.32 (G1), 2.49 (G2), 2.74 (G3), 2.99 (G4), and 3.24 (G5) Mcal/kg] until they were 9-month-old. After natural breeding, 50 female goats ($30.7{\pm}0.59kg$) were stratified by weight and randomly assigned into 5 groups. They were fed 5 diets varying in ME [2.32 (P1), 2.43 (P2), 2.55 (P3), 2.66 (P4), and 2.78 (P5) Mcal/kg]. The average feed intake ranged between 1.5 and 2.0% of the body weight (BW), and there was no significant difference between the treatment groups with goats in growth or pregnancy phases. Average daily gain (ADG) in diet demand during the growth phase increased with an increasing ME density and ranged from 46 to 69 g/d (p<0.01). Feed conversion ratio (FCR) improved with the ME density during the growth phase (p<0.01). The intercept of the regression equation between ME intake and ADG indicated that energy requirement for maintenance of goats during growth and pregnancy phases was $103.53kcal/BW^{0.75}$ and $102.7kcal/BW^{0.75}$, respectively. These results may serve as a basis for the establishment of goat feeding standards in Korea. Further studies are required to assess the nutrient requirement of goats using various methods for improving accuracy.

• Korea Science and Art Forum
• /
• v.37 no.5
• /
• pp.119-133
• /
• 2019

This study is as skyscrapers are becoming increasingly taller, more constructors have decided the height alone cannot be a sufficient differentiator. As a result, atypical architecture is emerging as a new competitive factor. Also, it can be used for symbolizing the economic competitiveness of a country, city, or business through its form. Before the introduction of digital media, there was a discrepancy between the structure and form of a building and correcting this discrepancy required a separate structural medium. Since the late 1980s, however, digitally-based atypical form development began to be used experimentally, and, until the 2000s, it was used mostly for super-tall skyscrapers for offices or for industrial chimneys and communication towers. Since the 2000s, many global brand hotels and commercial and residential buildings have been built as super-tall skyscrapers, which shows the recent trend in architecture that is moving beyond the traditional limits. Complex atypical structure is formed and the formative characteristics of diagonal lines and curved surfaces, which are characteristics of atypical architecture, are created digitally. Therefore, it's goal is necessary to identify a new relationship between the structure and forms. According to the data of Council on Tall Buildings and Urban Habitat (CTBUH), 100-story and taller buildings were classified into typical, diagonal, curved, and segment types in order to define formative shapes of super-tall skyscrapers and provide a ground of the design process related to the initial formation of the concept. The purpose of this study was to identify the correlation between different forms for building atypical architectural shapes that are complex and diverse. The study results are presented as follows: Firstly, complex function follows convergence form characteristics. Secondly, fold has inside of architecture with repeat. Thirdly, as curve style which has pure twist, helix twist, and spiral twist. The findings in this study can be used as basic data for classifying and predicting trends of the future super-tall skyscrapers.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2016.02a
• /
• pp.399.2-399.2
• /
• 2016

Cu(In,Ga)Se2 (CIGS) 박막 태양전지는 높은 효율과 낮은 제조비용, 높은 신뢰성으로 인해 박막 태양전지 중 가장 각광받고 있다. 특히 유리기판 대신 가볍고 유연한 철강소재나 플라스틱 소재를 이용하여 발전분야 외에 건물일체형, 수송용, 휴대용등 다양한 분야에 적용이 가능하다. 이러한 유연 기판을 이용한 CIGS 태양전지의 개발을 위해서는 기판의 특성에 따른 다양한 공정개발이 선행되어야 한다. Poly-imide와 같은 유연기판은 공정온도가 $400^{\circ}C$이하로 낮고 기판이 매우 얇아 기존 Mo 공정을 개선하여야한다. 이러한 유연기판의 특성을 고려하여 본 연구에서는 기존 bi-layer Mo의 bottom layer의 두께를 조절하여 박막의 strain을 조절하였다. 유연기판으로는 SKC KOLON에서 제조된 GL type의 기판을 사용하였다. 기판의 두께는 50um이다. 먼저 Mo의 bottom layer 두께 비율을 기존 12.5%에서 50%로 증가 시켰으며 전체 박막의 두께 역시 900nm에서 500nm로 두께를 감소시키며 실험을 실시하였다. 그 후 흡수층은 Co-Evaporation 방법을 이용하여 제조하였으며 이때 공정온도는 기존 공정온도에서 450, $400^{\circ}C$로 낮추어 흡수층을 제조하였다. 소자 제조 후 초기 Mo의 strain 개선과 저온공정이 적용되지 않은 경우 4.4%에서 공정 최적화 후 13%로 효율이 증가하였다. 제조된 흡수층은 SEM, XRF, XRD등을 이용하여 분석하였으며 그 외 일반적인 방법을 이용하여 Mo, CdS, TCO, Al grid를 제조하였다. AR 코팅은 제외 하였으며 제조된 소자는 솔라 시뮬레이터를 이용하여 효율 특성 분석을 실시하였으며 Q.E. 분석을 실시하였다.