• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.2
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• pp.134-140
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• 2021

This study was carried out to study the effect of supplementary nitrogen fertilization application time according to regrowth date on growth date on growth characteristics, feed value, and productivity of Italian ryegrass (Lolium multiflorum Lam.; IRG) from 2019 to 2021 in Cheonan region. In order to determine the regrowth time, IRG was cut from experimental plots 3cm above soil level and the time when 1cm grew was judged as the regrowth time. The regrowth dates were February 15^th and February 12th in 2020 and 2021 respectively. The experimental design was a randomized block design with three replications. The treatments were no fertilizer, immediately after the regrowth period, after 10 days of the regrowth period, and after 25 days of the regrowth period. Dry matter yield of IRG was significantly influenced by the supplementary N-fertilization application time. Dry matter yield was reduced for the delayed application time. The dry matter yield of immediately after the regrowth period was approximately 34.8 % higher than that no fertilizer application. In delaying the supplementary N-fertilization application time resulted in increased crude protein content. However, no significant statistical difference was neutral detergent fiber and acid detergent fiber(p>0.05). After wintering, productivity of IRG reduced for the delayed application time. Therefore, it is essential to application N-fertilizer immediately after the regrowth period for high productivity of IRG.

• Development and Reproduction
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• v.2 no.1
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• pp.53-62
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• 1998

The lysosomal acid hydrolases including lysosomal acid phosphatase (LAP) are believed to play an important role in intracellular and extracellular degradation. LAP was reported to increase its activity in dedifferentiation stage during urodele limb regeneration. In the paresent study, LAP localization in the Mexican axolotl (Ambystoma mexicanum) limb regenerates was investigated by immunohistochemistry. LAP immunoreactivity with monoclonal antibody against Korean salamander (Hynobius leehii) LAP was observed mainly in the wound epidermis, blastema cells, muscle, and cartilage which were under dedifferentiation process in axolotl limb regenerates. Moreover, LAP immunoreactivity increased gradually during the early phase of lib regeneration and reached the peak level at dedifferentiation stage. However, as redifferentiation begans, LAP immunoreactivity decreased slowly to the basal level. Retinoic acid (RA) which is known to induce skeleton pattern duplication in regenerating urodele limb appears to enhance LAP immunoreactivity. In the RA-treate limg regenerates, LAP immunoreactivity was higher than in the normal regenerates. In addition, the LAP expression period was more extended in the RA treated regenerates than in the normal regenerates. These results suggest that RA is involved in the extension of dedifferentiation state in RA-treated limb regenerate.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.29-34
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• 1987

The number of regrown shoots per plant for 2 weeks after mowing sharply increased in response to late mowing until June 6, and then the increments were slow. The number of regrown shoots for July 30 were many with early mowing until May 14, and then the numbers were rapidly decreased. The plant height regrown for 2 weeks after mowing was increased until May 14, and then decreased. The plant height regrown for July 30 was not sensitive to mowing time and the development was linearly shown. The fresh weight regrown for July 30 was only increased by late mowing. The regrowth rate of shoots for 2 weeks after mowing was much higher than untreated control and the ratio was decreased with late mowing and the ratio to untreated for control for July 30 was decreased up to 50% by late mowing. The regrowth rate of plant height for 2 weeks after mowing was rapidly decreased, but slowly decreased for July 30 mowing. The regrowth rate of fresh weight was higher until May 22, and then rapidly decreased by late mowing. The decreasing tendency for 2 weeks after mowing was more prominent them for July 30. The annual regrowth rates in shoots and plant height were slowly decreased, but the decreasing rate in fresh weight was rapidly done until May 15, and then decrement became up to 30% by late mowing.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.1
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• pp.15-20
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• 1990

This experiment was carried out to investigate the effects of the fist harvesting times (vegetative, stem elongation and heading stage) and regrowth periods (20, 30 and 40 days) after the first harvest on dry matter (DM) productivity, crude protein (CP), CP yield and cell wall constituents of gasses during 1987 and 1988. Although the dry matter productivity of grasses at the first was decreased with earlier cutting, the regrowth DM productivity after the first harvest was increased significantly with earlier cutting (p < 0.05). Also the 30 days of regrowth periods was contributed greatly to the DM productivity p <0.05). The percentage of leaf in the leaf: stem ratio was increased with earlier initial harvest and shorter regrowth period after first harvest. The nutritive value of grasses was increased with earlier initial harvest and the 30 days of regrowth period after fist harvest. Based on the results, it is suggested that good grass DM productivity and nutritive value could be achieved by the earlier harvest at first and the regrowth period of 30 days after first harvest in spring.

• The Korean Journal of Pesticide Science
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• v.6 no.1
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• pp.36-41
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• 2002

Characteristics of regrowth and starch degradation in perennial weed rhizomes were investigated in a greenhouse. Cyperus serotinus started regrowth at 24 days after treatment of 1.25 g ai/ha of pyrazosulfuron-ethyl. The regrowth of Sagittaria trifolia, Eleocharis kuroguwai, and S. pygmaea required $30{\sim}39$ days, and Potamogeton distinctus regrew at 55 days after treatment of 1.25 g ai/ha of pyrazosulfuron-ethyl. However, all of 5 perennial weeds hardly regrew until 45 days after treatment more than 5 g ai/ha of pyrazosulfuron-ethyl. Regrowth of C. serotinus 4-node rhizomes was 2 times higher than 2-node rhizomes, and $1{\sim}1.5g$ of E. kuroguwai large tubers regrew faster than $0.3{\sim}0.5g$ of small tubers treated with bensulfuron-methyl. Regrowth of C. serotinus was enhanced with delayed application of bensulfuron-methyl, however, 2-leaf stage of E. kuroguwai plants regrew better than 3 leaf stage of plants when treated with equal volume of bensulfuron-methyl. The critical periods of S. trifolia and E. kuroguwai growth depending upon the rhizome detachment were 12 and 18 days after sprouting, respectively. The starch stacked in the S. trifolia and E. kuroguwai tubers were exhausted at 18 and 27 days after sprouting, respectively. The highest level of sugar contents was showed at 9 days after sprouting in S. trifolia, and 18 days after sprouting in E. kuroguwai.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.139-145
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• 2011

The practice of asphalt pavement recycling has grown rapidly over the decade, one of which is the cold in-place recycling with the foamed asphalt (CIR-foam) or the emulsified asphalt (CIR-emulsion). Particularly, in Iowa, the CIR has been widely used in rehabilitating the rural highways because it significantly increases the service life of the existing pavement. The CIR layer is typically overlaid by the hot mix asphalt (HMA) to protect it from water ingress and traffic load and obtain the required pavement structure and texture. Most public agencies have different curing requirements based on the number of curing days or the maximum moisture contents for the CIR before placing the overlay. The main objective of this study is to develop a moisture loss index that the public agency can use to monitor the moisture content of CIR layers in preparation for a timely placement of the wearing surface. First, the moisture contents were measured in the field using a portable time domain reflectometry (TDR) device. Second, the weather information in terms of rain fall, air temperature, humidity and wind speed was collected from the same location. Finally, a moisture loss index was developed as a function of initial moisture content, air temperature, humidity and wind speed. The developed moisture loss index based on the field measurements would help the public agency to determine an optimum timing of an overlay placement without continually measuring moisture conditions in the field.

• JOURNAL OF ELECTRICAL WORLD
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• s.425
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• pp.60-64
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.51-55
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• 1996

본 연구에서는 숫돌면의 직접관찰에 의해 적정한 드레싱 시기를 결정하는 것에 관한 연구를 수행했다. 이를 위해, 와전류센서를 숫돌주위에 설치하여 숫돌면의 눈막힘량을 비접촉식으로 직접 측정하므로서 숫돌의 상태를 검출했다. 숫돌의 재생작용에 의한 정상연삭과 눈막힘에 의한 이상연삭의 구분은 검출된 눈막힘량과 가공면 표면거칠기의 상관괘적(Relational Locus)을 통해 드레싱 시기를 결정했다. 또한 이때의 숫돌면의 상태를 레이져 변위센서를 이용해 측정하고 3차원 Topography로 표현했다. 본 논문에서는 이러한 내용들에 대한 실험적 결과들을 소개한다.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.300-300
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• 2009

Outcome Evaluation은 미국의 DOE(Department Of Energy)산하 EERE(Energy Efficiency and Renewable Energy)에서 프로그램 평가를 위해 사용하는 General Program Evaluation Guide에서 언급된 5가지 평가방법 중 하나로 프로그램의 결과를 측정하여 평가하는 방법이다. 이는 프로그램을 시행한 후 일정한 기간이 지난 뒤 프로그램의 목적을 달성함으로써 얻어지는 결과를 추산하여 그 기간 동안 프로그램이 의도했던 목적을 위해 얼마나 잘 수행되었는지를 보여준다. 본 연구에서는 Outcome Evaluation을 이용하여 한국에서 진행되고 있는 신재생에너지 보급사업에 대한 평가를 하였다. 현재 한국의 신재생에너지 보급사업은 크게 보급지원제도와 기반조성사업으로 나누어져 있으나 본 연구에서는 보급지원제도에 중점을 두어 평가를 진행하였다. General Program Evaluation Guide에 따르면 Outcome Evaluation의 방법론은 engineering estimation에서 survival analysis에 이르기까지 다양한 방법론을 제시하지만 본 연구에서는 Tabulation과 Correlation을 주로 활용하였다. 먼저 평가의 대상이 되는 프로그램과 시기를 정하고 평가지표를 산정한 뒤 위와 같은 방법론을 활용해 평가를 진행했고, 그 시사점을 도출하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.518-518
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• 2022

오늘날 우리사회는 환경변화와 기후 위기 가속화로 인하여 삶의 질 악화는 물론 인류 생존까지도 걱정해야 시기에 이르렀는데, 이러한 변화의 주범인 온실가스의 75%가 도시에서 발생되고 있다(Global Sustainable Development Repor, 2019), 이에 국제 사회는 도시 중심의 녹색 전환 정책 추진 중인데, 우리나라는 2017년부터 '도시재생뉴딜사업'을 추진하고 있다. 이에 본 연구는 지자체가 주도적으로 환경성과 창출 방안을 마련, 도시의 지속가능성 높이는데 일조하고자 탄소중립 선도 도시 사례와 도시재생의 문제점을 살펴봄으로써 도심 내 과밀화 문제와 탄소배출 해결 방안을 제시하였다. 당초 '도시재생뉴딜' 사업은 도시의 다양한 니즈를 충족시키기 위하여 시작되었으나, 최근에는 도시 노후화와 탄소배출 문제에 대응하기 위하여 '그린도시', '친환경 도시'를 지향하고 있다. 그러나 이를 뒷받침할 법·제도의 제·개정 및 이를 바라보는 이해관계자의 시각 전환이 이루어지지 않아 크고 작은 많은 문제점이 발생하고 있다. 도시재생의 첫 번째 문제점은 정책지원의 30% 이상이 일반근린형에 집중됨에 따라 주거형 도시재생 양상을 띄고 있다는 점이다. 이는 임기가 제한된 지자체장이 가시적인 성과를 위하여 도시 내 인프라 확충에 집중한 결과로 지속가능한 도시재생을 저하시키는 요인이 되고 있다. 두 번째, 도시재생 뉴딜사업이 계획수립과정에서 지속가능성에 대한 검토와 환경성 평가에 대한 고려 부족으로 기후 위기 대응에 미흡한 실정이다. 노후 도시의 주거 과밀화 문제를 해결하고 효과적인 도시 탄소 감축을 위하여 건물 - 마을 - 도시 등 여러 공간 단위의 온실가스 배출량 감축 전략 수립이 필요하다. 세 번째, 치·이수 위주의 도시재생 뉴딜사업으로 탄소 중립 대책이 미흡하다. 대응 방안으로는 자원의 관점에서 물 소비 감소 촉진 및 재생에너지 증가 전략이 필요하다.