• 한국초지조사료학회지
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• 제40권3호
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• pp.123-130
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• 2020

These experiments were to investigate the variations of rye on forage quality, productivity and β-carotene concentration affected by maturity in Pyeongchang region. Limited information are available about how forage quality and β-carotene content are affected by various factors. Samples were collected from rye harvested every 5 days, from April 25 to May 31 (April 25, April 30, May 4, May 9, May 15, May 21, May 25 and May 31). Dry matter (DM) content, plant height, DM yield and total digestible nutrient (TDN) yield increased continuously with the progressed maturity. However, crude protein (CP) content, in vitro dry matter digestibility (IVDMD) and relative feed value (RFV) decreased markedly with the delay of harvesting, while TDN content decreased from April 25 till May 15, then followed by a stable fluctuation. Conversely, acid detergent fiber (ADF) and neutral detergent fiber (NDF) value increased and then fluctuated slightly after blooming stage. For quality of plant parts, stem contained the lowest CP content and RFV value, and the highest ADF and NDF contents compared with other parts, while the grain showed the higher CP, IVDMD, RFV and lower fiber contents than others. With the plant matured, leaf proportion decreased while stem and grain proportion increased, and feed value of all the three parts decreased till blooming stage and followed by a stable phase. β-carotene concentration showed its highest on jointing stage, and then fell down sharply on the sequential stages. In conclusion, harvest around May 15 (blooming) is proper for forage rye if directly consumed by livestock as green chop in Pyeongchang under the consideration of both nutritive yield and forage quality.

• Journal of Microbiology and Biotechnology
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• 제25권9호
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• pp.1547-1554
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• 2015

The potential of microalgae biofuel has not been realized because of the low productivity and high costs associated with the current cultivation systems. In this study, a new low-cost and transparent attachment material was tested for cultivation of a filamentous algal strain, Stigeoclonium sp., isolated from wastewater. Initially, the different materials tested for Stigeoclonium cultivation in untreated wastewater were nylon mesh, polyethylene mesh, polypropylene bundle (PB), polycarbonate plate, and viscose rayon. Among the materials tested, PB led to a firm attachment, high biomass (53.22 g/m², dry cell weight), and total lipid yield (5.8 g/m²) with no perceivable change in FAME profile. The Stigeoclonium-dominated biofilm consisted of bacteria and extracellular polysaccharide, which helped in biofilm formation and for effective wastewater treatment (viz., removal efficiency of total nitrogen and total phosphorus corresponded to ~38% and ~90%, respectively). PB also demonstrated high yields under multilayered cultivation in a single reactor treating wastewater. Hence, this system has several advantages over traditional suspended and attached systems, with possibility of increasing areal productivity three times using Stigeoclonium sp. Therefore, multilayered attached growth algal cultivation systems seem to be the future cultivation model for large-scale biodiesel production and wastewater treatment.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.910-917
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• 2015

A total of 646 strains, including green algae and diatoms, were isolated from 220 samples to screen microalgae with high lipid productivity (LP). The samples were obtained from nine habitats in Northern Xinjiang, China in June 2013. This study initially identified eight lipidrich strains, namely, Desmodesmus intermedius XJ-498, D. intermedius XJ-145, D. intermedius XJ-99, Monoraphidium pusillum XJ-489, M. dybowskii XJ-435, M. dybowskii XJ-151, Mychonastes homosphaera XJ-488, and Podohedriella falcata XJ-176, based on 18S rDNA sequencing. The strains were cultured in a photobioreactor for the same period. Results showed that the specific growth rate (day^-1) of M. pusillum XJ-489 was the highest (1.14 ± 0.06), and the biomass concentration (g/l) of D. intermedius XJ-99 was the highest (2.84 ± 0.3). Futhermore, the lipid content (%) of M. dybowskii XJ-151 was the highest (33.5 ± 4.38), and the lipid productivity (mg l^-1 day^-1) of My. homosphaera XJ-488 was the highest (86.41 ± 9.04). C16 to C18 accounted for 86% to 98% of the total lipid, and the biodiesel qualities of the selected algae corresponded to international standards. This study suggests that My. homosphaera XJ-488, D. intermedius XJ-99, and M. dybowskii XJ-151 are the most potential strains for biodiesel production among all the isolated strains.

• KSBB Journal
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• 제24권1호
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• pp.96-100
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• 2009

본 연구에서는 저온에서의 재조합 단백질 생산성 향상을 위하여 저온에서 RNA 샤페론 활성을 지닌다고 알려진 CspA 단백질의 발현이 서로 다른 온도에서 대장균의 성장 및 GFP의 발현 속도에 어떻게 영향을 미치는지를 살펴보았다. $20^{\circ}C$, $25^{\circ}C$, $37^{\circ}C$에서는 세포 성장 및 GFP의 생산이 CspA의 발현에 영향을 받지 않았으나, $15^{\circ}C$에서는 GFP의 총 생산성이 CspA의 동시 발현에 의해 향상되었으며 이는 세포 성장 속도의 향상에 기인함을 확인하였다. 결론적으로 CspA의 발현은 $15^{\circ}C$에서 세포 당 재조합 단백질 생산량의 증가에는 영향을 미치지 않으나, 즉 재조합 단백질의 번역 효율에는 큰 영향을 미치지 않으나, 대장균 성장 속도에 영향을 미치며, 이를 통해 재조합 단백질의 총 생산량 향상을 유도 할 수 있을 것으로 기대된다.

• 자원리싸이클링
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• 제25권3호
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• pp.37-42
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• 2016

폐 젤리충진 케이블로부터 고순도 구리 와이어를 높은 회수율과 생산성으로 회수할 수 있는 친환경 공정을 개발하였다. 두 롤러(roller) 사이에 폐 케이블을 공급해주고 롤러의 밀착 압력이 외피(주로 polyethylene)의 인장강도 이상이 되면 자연스럽게 구리 심선과 외피로 분리되도록 한 단순한 기계적 방법만을 적용한 친환경 공정을 개발하였으며, 연속공정을 위한 세부 요소기술을 접목하고 이를 실험적으로 검증하였다. 연속공정을 통한 구리 와이어 평균 회수율은 98% 이상, 처리속도는 55 Kg/hr이었으며, 상업화 공정을 위한 진일보된 공정으로 평가될 수 있다.

• 한국토양비료학회지
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• 제45권6호
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• pp.1094-1099
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• 2012

담수조건으로 토양질소동태에 대한 결실기 자운영의 투입효과를 포트시험을 통해 평가하였다. 자운영의 투입에 따라 벼의 자운영유래 질소 이용율은 약 51-64%으로 자운영의 투입량이 높을수록 감소하였다. 수확기 토양의 자운영질소는 약 3-5%가 저장되었고, 자운영 유래 질소의 손실은 각각 32.4와 44.1%를 차지하였다. 벼 수량 대비 자운영 $30Mg\;ha^{-1}$ 시용은 질소추천시비량을 전량 대체할 수 있었다.

• 한국태양에너지학회 논문집
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• 제34권5호
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• pp.43-52
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• 2014

A plant factory system is getting the spotlight as alternatives to cope with the weather anomaly and food crisis because of the global warming. A study on 'Plant Processing Factory System' has been proceeded to develope 'low-carbon green growth' since our government selected it as the green technologies in 2010. The plant factory has played a major role in growth industries connected to many other fields like low-carbon as well as lighting and automated system. This study is aimed to solve the problems on low productivity and health problem of plant workers caused by highly concentrated carbon dioxide and low temperature in each process in the plant factory. It is aimed to research data to understand the actual conditions of plant workers and improve the thermal environment.

• Journal of Welding and Joining
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• 제35권2호
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• pp.35-42
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• 2017

The GMA welding process involves large number of interdependent variables which may affect product quality, productivity and cost effectiveness. The relationships between process parameters for a vertical weldment and mechanical properties are complex because a number of process parameters are involved. To make the vertical-position welding, a method that predicts bead geometry and accomplishes the desired mechanical properties of the weldment should be developed. In addition, a reliable welding process and conditions must be implemented to reduce weld structure failure. In this study, the welding process analysis of investigates the interaction between the heat input and welding parameter(Welding current, Arc voltage, Welding speed) for predicting the weldment hardness.

• 국제학술발표논문집
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• The 5th International Conference on Construction Engineering and Project Management
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• pp.36-41
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• 2013

With the increased interest in green buildings, the building industry has been experiencing a fast-growing demand for LEED (Leadership in Energy and Environmental Design) certification for the last decade. Still, it is not unusual to see various barriers and issues during its implementation, and experience tells that they can result in harming the overall project performance with reworks, lower productivity, schedule delays, and cost overruns. In order to better understand the industry's observation on issues and their consequences during LEED implementation, we distributed an online survey, and a total of 53 responses were received. The survey results indicate that (1) both designers and non-designers (e.g., contractors) select 'added costs to design and construction' as the biggest barrier; (2) both designers and non-designers select 'decision made too late in the design process' as the most frequently observed issue; and (3) non-designers indicate higher perceived severity in every consequence criteria than designers. The statistical analyses reveal that cost overruns are the most severe impact observed and have a statistically significant relationship with responses in regard to the barrier to LEED implementation.

• 한국초지조사료학회지
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• 제37권2호
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• pp.161-167
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• 2017

본 시험은 강원 평창지역에서 수입적응성 인증 품종간의 생산성 비교를 통하여 우수한 품종을 선발하기 위하여 수행되었다. 총 8개의 품종 중에서 생선성이 우수한 사일리지용 옥수수 품종을 선발하기 위하여 수행하였다. 총 8개의 품종(광평옥, 31N27, 32P75, 32W86, P3156, P3394, DK689 및 DK729) 을 대상으로 시험구는 8처리 난괴법 3반복으로 배치하였다. 옥수수 재배는 서울대학교 평창캠퍼스에 조성된 시험포장에서 2015년 5월 1일부터 9월 2일까지 수행하였으며 시험구 크기는 $15m^2$으로 하였다. 초장은 32W86 품종이 가장 컷으며 광평옥의 착수고가 가장 높았다 (p<0.05). 출수 및 출사기는 7월 27-8월 3일 사이로 늦은 편이었으며 출수 1-3일후에 출사하는 것으로 나타났다. 출사소요일수는 평균 92일이었고 31N27이 가장 적었으며 (p<0.05), DeKalb 품종들이 많았다. GDD는 평균 $1,023^{\circ}C$이었으며 P3394 품종의 GDD가 가장 낮았다. 저항성 평가에서 질병은 P3394가 가장 낮았고 곤충은 P3156 품종에서 낮았다. 모든 품종에서 도복은 발생하지 않았으며 DK 729 품종의 후기 녹체성이 가장 우수한 것으로 나타났다 (p<0.05). 전체 건물함량은 평균 30.77%로 높은 편이었으며 32W86품종의 건물함량이 가장 높았으나 통계적 유의성은 없었다 (p>0.05). 암이삭 무게는 32W86품종이 가장 무거웠으며 광평옥이 가장 적었다. 암이삭 비율은 32W86 및 P3394 품종이 높은 경향을 나타내었으나 통계적인 차이는 인정되지 않았다 (p>0.05). 품종에 따른 평균 생초수량은 59,017kg/ha이었으며 유의적인 차이는 없었다 (p>0.05). DK 689품종의 건물수량이 높아으나 유의성은 없었고 TDN 수량 역시 DK 689 품종이 가장 높았다. 이상의 결과를 종합하여 볼 때 수입적응성 인중 품종간의 생산성은 차이가 없었으나 안정적인 재배를 위해서는 광평옥, 32W86 및 32P75품종이 유리할 것으로 판단된다.