• Plant Resources
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• 제7권3호
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• pp.206-210
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• 2004

In order to find out the optimum harvest (dipping) date combined with sowing date on yield and nutrient quality of forage rye which is suitable at the Southern part of Korea, Paldanghomil variety was grown Sep. 2001 to May 2002 at Sunchon National University, and yield and nutrient quality of plant were observed. As harvest date and sowing date were delayed, the plant length was longest, number of leaves per plant was increased in the time of May 20 clipping. Fresh yield was the heaviest in the time of May 20 clipping and Oct. l0 sowing, and the most dry matter yield was the heaviest in the time of May 20 clipping and Oct. 10 sowing. Content of crude protein was the highest and that of crude fiber such as NDF, ADF, hemicellulose, cellulose and lignin were the lowest in the late time of clipping and sowing. Further more IVDMD was high and dry matter yield and digestible dry matter yield were the highest in the time of May 20 dipping and Oct. 10 sowing. Judging from the results reported above, at optimum harvest (dipping) date combined with sowing date for yield and nutrient quality of forage rye seemed to be the time of May 20 clipping and Oct. 10 sowing.

• Plant Resources
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• 제8권3호
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• pp.258-262
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• 2005

In autumn, to determine the optimal planting date and plant density of rapeseed in southern areas of Korea, Yudal variety for autumn sowing, the highest yielding variety was grown under three different planting dates and five different plant densities. Yield components such as plant height, ear length, number of seedling stand per $m^2$, number of branches and pod length were highest at the plots with Sep. 30 of planting date and 30/20 cm drilling of plant density. Yield of seed, oil and 1,000 grains weight were highest at the Sep.30 of planting date and 30/20 cm drilling of plant density. Judging from the results reported above, at optimum planting date and plant density of rapeseed seemed to be Sep.30 of planting date and 30/20cm plant density in autumn sowing.

• 한국작물학회지
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• 제60권2호
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• pp.197-211
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• 2015

우리나라 중부지역에서 파종기이동과 멀칭유무에 따른 조, 기장, 수수의 최적파종기 및 파종한계기 구명을 위하여 5월 15일, 6월 6일, 6월 26일, 7월 13일 파종기를 4수준으로 하여 피복 및 무피복을 처리하였다. 시험품종은 조 4품종(삼다찰, 삼다메, 경관1호, 황금조), 기장 4품종(이백찰, 만홍찰, 황실찰, 황금기장), 수수 4품종(남풍찰, 황금찰, DS202, 목탁수수)을 국립식량과학원 기능성작물부와 농업기술실용 화재단에서 분양받아 2013년 경기도 안성시에서 실시한 시험결과를 요약하면 다음과 같다. 1. 간장은 조, 기장, 수수 모두 6월 6일 파종기에서 가장 컸다. 2. 수장은 조, 기장은 5월 15일 파종기에서 가장 컸고 수수는 6월 26일 파종기에서 가장 컸다. 3. 엽수는 조, 기장, 수수 모두 5월 15일 파종기에서 가장 많았다. 4. 조의 출수소요일은 파종기가 늦어짐에 따라 삼다메와 경관1호, 삼다찰은 감소하였고 황금조는 1차 파종기인 5월 15일부터 3차 파종기인 6월 26일 파종기까지는 감소하다가 7월 13일 4차 파종기에서는 6월 26일 파종기와 같았다. 기장의 출수소요일은 4품종 모두 파종기가 늦어짐에 따라 감소하였다. 수수의 출수소요일도 4품종 모두 파종기가 늦어짐에 따라 감소하다가 마지막 파종기인 7월 13일에는 증가하였다. 5. 멀칭 및 무멀칭구 간에는 조, 기장, 수수 3작물 모두 생육 및 수량 특성간 유의적인 차이가 없었다. 6. 1수립수, 천립중 및 10당 수량은 조, 기장, 수수 모두 6월 26일 파종기에서 가장 높았다. 중부지방에서 조, 기장, 수수의 최적 파종기는 6월 하순으로 판단된다. 7. 7월 13일 파종기에서는 황금조, 만홍찰, 황금기장을 제외한 나머지 품종들은 만파로 인하여 성숙기에 이르지 못하였다. 중부지방에서 조, 기장, 수수의 파종 한 계기는 7월 초순으로 판단된다.

• 경영과학
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• 제13권2호
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• pp.147-161
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• 1996

Due-date is an important factor in Flexible Manufacturing System scheduling. Even though most of researchers have focused part selection and loading problem using fixed due-date assignment rules, FMSs consist of multi-function machines which facilitate alternative processes. This research investigates interactions of three dispatching mechanisms, three NSS (Next Station Selection) rules and four due-date assignment rules using simulation. Both cost-based and time-based performance measures are considered in this research.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.250-250
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• 2017

Studies were conducted to select the optimum sowing date and planting density of sesame in the middle area of Korea. To select the optimum sowing date, sesame seeds sowed from 20 April to 7 July with 15-day intervals. To select the optimum planting density, sesame seeds investigated under four different planting distances ($30{\times}10,\;30{\times}15,\;30{\times}20$, and $30{\times}25cm$)respectively in the experimental field. As seeding date was delayed, days to emergence were shortened flowering and maturing date were delayed. Delayed sowing date resulted in decreased length, capsule setting stem length and number of capsules, and branchs per plant. Number of Capsules was high sowing date on 5 May in the range of 90~95ea/plant in sesame. Also yield of sesame seeds was most high on 5 May in the range of 142kg/10a by sowing date. Sowing date up to 5 May showed no effect on grain yield, but from 5 June to 5 July decreased 27%, 68% and 86%, respectively. For all planting distances, weight of 1,000 grain was not significantly different. However, number of branches and capsules tended to increase. Number of Capsules was high planting distance of $30{\times}20cm$ and $30{\times}25cm$ in the range of 146.7~165.7ea/plant in the Geonbaekkae. Areumkkae also showed the same tendency on planting distance of $30{\times}20cm$ and $30{\times}25cm$ in the range of 122.0~147.5ea/plant, respectively. Yield of Geonbaekkae and Areumkkae seeds was most high 116kg/10a, 117kg/10a, respectively on planting distance $30{\times}20cm$. Decreased in the planting distance of sesame has increased the incidence of disease and lodging. Based on the results, we suggest a planting distance of $30{\times}20cm$ maximal growth and yield of sesame in the middle area of Korea. Considering growth characteristics, sesame yield ability, the optimum sowing date was 5 May and optimum planting pattern was founded to be two rows planting in one ridge and planting densities was $30{\times}20cm$.

• Asian-Australasian Journal of Animal Sciences
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• 제14권12호
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• pp.1705-1711
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• 2001

Silage corn (Zea mays L) is grown extensively in livestock operations, and many managements focus on forage yield. This experiment was conducted at Seoul National University (SNU) Experimental Livestock Farm, Suwon in 1998. We determined the effect of planting date and harvest stage on forage yield and quality responses of corn hybrids (five relative maturity groups). The five maturity groups (100 d, 106 d, 111 d, 119 d and 125 d) were planted on 15 April and 15 May, and harvested at maturity stages (1/3, 1/2 and 2/3 kernel milkline). Whole plant dry matter (DM) and ear percentages had significant differences among corn hybrids. Ear percentages of early maturing corns (100 d and 106 d) were higher than for other hybrids. Ear percentage at the early planting date was higher than that at the late planting date for all corn hybrids. The DM and total digestible nutrients (TDN) yields of the 106 d and 111 d corn hybrids were higher than other hybrids, and the DM and TDN yields at the early planting date were higher than that at the late planting date. The acid detergent fiber (ADF) and neutral detergent fiber (NDF) percentages were greater for the late maturity corn hybrids. For plants of the early planting date, the ADF and NDF percentages were lower than for those of late planting date for hybrids. From the comparison among harvest stages, ADF and NDF percentages were decreased as harvest stage progressed. The TDN, net energy for lactation (NEL), and cellulase digestible organic matter of dry matter (CDOMD) were decreased as maturity of corn hybrid delayed. The TDN, NEL, and CDOMD values at the early planting date were higher than those at the late planting date among for corn hybrids. From the comparison among harvest dates, TDN, NEL, and CDOMD values were increased as harvest stage progressed. The correlation coefficient for DM percentage of grain at harvest with DM and TDN yields were 0.68*** and 0.76***, respectively. And the correlation coefficient for ear percentage with ADF, NDF, and CDOMD were -0.81***, -0.82*** and 0.73***, respectively. Our study showed differences of silage corn in forage production and quality resulting from hybrid maturity, planting date, and harvest stage. We believe that for the best silage corn, selection of the hybrid and best management practices are very important.

• 한국작물학회지
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• 제40권1호
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• pp.44-51
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• 1995

도입에 의존하고 있는 풋콩 종자 생산체계를 확립하고자 조숙성 품종인 큰올콩과 풋콩 도입풍종인 Fukura 피두를 평야지（영남농업시험장） 및 고랭지（경남 밀양군, 사자평 ：해발 850m）에 파종시기（5월 15일, 6월 15일, 7월 15일）를 달리하여 생육 및 수량과 병해립 및 저장후 발아력을 조사한 결과를 요약하면 다음과 같다. 1. 파종시기가 빠를수록 협수가 많고 100립종은 무거웠으며 수량도 높았다. 재배지별로는 평야지가 고랭지보다 증수되었고, 큰올콩이 Fukura보다 수량성이 높았다. 2. 남부지방의 산간 고랭지는 평야지에 비해 생육 및 100립종이 저하하고 수량성이 크게 떨어져 평야지보다 불리하였다. 3. 안전립 수량은 파종시기가 빠를수록 높고, 평야지 및 큰올콩품종에서 증수되었으며, 전체 립종에 대한 안전립 비율은 고랭지에서 높게 나타났다. 4. 파종시기에 따른 병해정도는 큰올콩은 뚜렷한 차이가 없었으나 Fukura는 파종기가 빠를수록 나병립율이 높았고, 미이라병은 파종기가 빠를수록 심하게 발생하였으며 자정병은 파종기가 늦을수록 많이 발생하는 경향이었다. 5. 종자의 발아율은 파종기가 늦은 것이 높았으며, 5월 15일에 파종하여 수확ㆍ저장한 종자의 발아율은 매우 낮아 문제시 되었다. 따라서 풋콩 종자생육을 위한 적정파종시기는 수파기의 고온ㆍ다습한 환경을 고려하여 6월 중순경이 좋을것으로 생각되었다.

• 한국초지조사료학회지
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• 제21권4호
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• pp.217-224
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• 2001

In order to identify the growth characterization, the yield and chemical composition of Jeju barnyard grass (Echinochloa crusgalli var. fiurnentacea(Roxb) Wight) based on seeding date in Jeju region, seeding carried out the 10-day intervals from March 27 to September 30 in 2000, respectively. Plant height was 143.2 cm, showing the highest on seeding date, April 6 among that of any other seeding date. On the other hand, those of early and late seeding gradually decrease. Plant height was 119.2 an in May 16 seeding. The results of stem diameter, number of withering leaves, number of leaves and fresh weight per plant were similar to those of the plant heights. The yield of fresh, dry matter forage, crude protein and TDN found the highest on April 6 seeding, 63.5 MT/ha, 13.9 MTha, 1.1 MT/ha, and 7.6 MT/ha, respectively. In early and late seeding, the yield was gradually decreased. In seeding May 16, the yield found .38.2 MTIha in fresh forage, 6.2 MTha in dry matter forage, 0.7 MT/ha in crude protein and 3.7 MTha in TDN, respectively. According to delaying the seeding date, March 27 to May 16, the contents of crude protein (from 7.9 to 10.8%), ether extract (from 4.6 to 6.0%), nitrogen free extract (from 45.1 to 46.5%), and TDN (from 54.2 to 60.8%) were gradually increased, respectively. On the other hand, those of crude fiber (from 28.9 to 25.6%) and crud ash (from 13.5 to 11.2%) were decreased. These results showed that April 6 was the optimum seeding date with the sole object of feed production of Jeju barnyard grass under the environmental condition like as atmospheric phenomena and soil in Jeju region. (Key words : Jeju barnyard grass, Seeding date, Forage yield, Chemical composition)

• Journal of Ecology and Environment
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• 제29권5호
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• pp.461-467
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• 2006

The growth pattern and the seasonal changes in nutrient contents of Humulus japonicus were investigated. Stem length of H. japonicus reached the maximum from 240 to 260 Julian date and the median value was found at 255 Julian date. The maximum leaf area was observed from 235 to 248 Julian date and the median value was at 240 Julian date. The maximum growth rate of the stem length ranged from 205 to 227 Julian date. The leaf area showed the maximum growth rate from 196 to 214 Julian date. The median date in the growth rate of the stem length and leaf area was 212 and 205 Julian date, respectively. The growth rate of H. japonicus was related to rainy season and precipitation. Phosphorus and sodium contents of H. japonicus were correlated with maximum potential rate of relative growth. Although stem biomass of H. japonicus was $ 1.5{\sim}3.5$ times larger than that of leaf, N content of the leaf ($4.48{\sim}5.27%$) was about 2 times higher than that of the stem ($2.00{\sim}3.62%$). High content of N might be responsible for the high growth rate of H. japonicus in summer. This result provides valuable information for appropriate timing for the removal of H. japonicus.

• 융합정보논문지
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• 제11권2호
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• pp.82-89
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• 2021

본 연구의 목적은 투자자의 은퇴 시점뿐만 아니라 시장의 예측 변동성을 동시에 고려하여 Target Date Fund의 위험자산 편입 비율을 동적으로 조정하는 새로운 Glide Path를 제안하고, 은퇴 시점만 고려하여 위험자산 편입 비율이 정해지는 전통적 Glide Path와 투자 성과를 비교 분석하는 것이다. 시장 변동성의 예측치로는 역사적 변동성, 시계열모형인 GARCH 변동성, 그리고 변동성지수인 VKOSPI를 활용하였으며, 2003년부터 2020년까지의 분석 기간에서 변동성을 고려하는 새로운 동적 Glide Path의 투자 성과가 우수함을 보여주었다. 3가지 변동성 예측모형 모두에서 은퇴 시점만을 고려하는 Glide Path보다 수익률은 더 높고 위험은 더 낮아지면서 투자 성과 지표인 Sharpe Ratio가 개선되었다. 실증 분석 결과는 은퇴예정자뿐만 아니라 Target Date Fund 운용업계에 새로운 Glide Path의 활용 가능성을 제시하고 있다.