• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.5B no.2
• /
• pp.97-102
• /
• 2005

Because of the limited fossil resources and the need to avoid emissions and toxic waste the future energy supply will be based on a large portion of renewable energies: wind-, solar-, biomass- and geothermal energy. Focus is on the utilization of wind energy coming from onshore- and offshore-sites. Generating electricity from wind is state of the art and feeding large amounts of wind power into the electrical grid will create some additional problems. Suggestions concerning energy storage will be made and the problem of power quality is discussed.

• Journal of Bio-Environment Control
• /
• v.11 no.1
• /
• pp.12-17
• /
• 2002

Tn establish the criteria for appropriate seedling production method in the summer, the effect of container size and seedling age on the growth and yield were evaluated with tomato. The seedling quality was higher when seedlings were grown polyethylene in 9cm pots than in 72 cell plugs. Seedling quality increased with increase in seedling age in polyethylene pots, whereas seedling age did not affect seedling quality in plug trays. Fruits matured earlier on plants started from pot-grown transplants for a long duration than with plug tray-grown transplants for a shorter duration. Not only total yield in 4 months, but the early yield in the first 2 months, was higher with pot-nursed transplants than with plug tray-nursed transplants. With pot-grown transplants, The early yield in initial 2 months was the lowest in 25 day-old transplants, whereas there was no significant differences between 35- and 45-day-old transplants. Seedling age did not affect the cumulative yield for 3 months after the first harvest. With plug tray-grown transplants, the cumulative yield tar initial 3 months was the highest in plants grown for 35 days in the nursery, followed by 25 day and 45 day. However, there were no significant differences among seedling ages in the total yield.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.16 no.4
• /
• pp.275-282
• /
• 1996

This experiment was canied out to investigate the effect of pasture types(mixture and mono tall fescue pasture) and endophyte infection on the dry matter yield, forage quality and animal performance of pasture plants at the Experimental Field of Grassland and Forage Crops Division, National Livestock Research Institute, Suweon, in 1994. The results obtained are surmmarized as follows : DM yield of tall fescue monoculture was significantly higher(p<0.05) than that of mixture pasture, while DM yield of endophyte-infected pasture was significantly higher(p<0.05) than that of endophyte-free for two pasture types. Crude protein yield(CPY) of tall fescue monoculture was significantly higher(p<0.05) than that of mixture, and the higher CPY with endophyte-infect tall fescue for both pasture types resulted from higher DM yield of the pastures. NDF and ADF contents of pasture plants were not influenced by pasture types, and there was no difference for NDF and ADF contents between endophyte-infect and -free pasture mixture, however, those of pasture plants were increased with endophyte-infect tall fescue in monoculture. IVDMD of pasture plants was increased with mixture and endophyte-free tall fescue for both pasture types. IVDMD of pasture plants was greatly influenced by pasture types and endophyte infection. There were no significant differences in average daily gain of Korean native cattle between pasture types, but those of the cattle were significantly increased with endophyte-free tall fescue for both pasture types(p<0.05). Based on the results of this experiment, it is suggested that a slightly more forage yield could be obtained , from monoculture and endophyte-infected tall fescue. However, liveweight gain was increased by mixture and endophyte-free tall fescue with good quality.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.4
• /
• pp.335-340
• /
• 1989

In order to find out the optimum harvest (clipping) date combined with sowing date on yield and nutrient Quality of forage rape which is suitable at the southern part of Korea, Velox, introduced variety was grown from Sep. 1987 to May 1988 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 branch and leaves per main stem were increased in the time of full bloom clipping and Sep. 24 sowing but stem diameter was thickest in the early sowing. Fresh yield was heaviest in the time of flowering clipping and Sep. 24 sowing but the most dry matter yield was heaviest in the time of full bloom clipping and Sep. 24 sowing. Content of crude protein was highest and that of crude fiber such as NDF, ADF, hemicellulose, cellulose and lignin were lowest in the late time of clipping and sowing. Further more IVDMD was high and dry matter yield and digestible dry matter yield were highest in the time of flowering clipping and Sep. 24 sowing. Judging from the results reported above, at optimum harvest (clipping) date combined with sowing date for yield and nutrient Quality of forage rape seemed to be the time of flowering clipping and Sep. 24 sowing.

• Korean Journal of Plant Resources
• /
• v.30 no.1
• /
• pp.78-87
• /
• 2017

This study was compared to outdoor field (OF) and rain shelter greenhouse (RSG) according to cultivation type of Gastrodia elata Blume. Also, the effects of yield and quality for mulching materials in RSG were compared. The yield of G. elata was investigated good merchantable quality, and the quality was investigated hardness, chromaticity, weight loss and the contents of the major functional components. The cultivation of RSG was increased the yield, hardness, gastrodin, and vanillyl alcohol compared to OF, and the weight loss, chromaticity, and ergothioneine were almost equal. Rice straw treatment showed higher than those of the control and other treatments on the yield and hardness. As a result, the yield and the quality of RSG, which can control the soil moisture, were better than that of OF. And the lower the soil moisture content according to the mulching material, the harder the surface and the higher the hardness.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.41 no.3
• /
• pp.147-154
• /
• 2021

Cutting management has been identified as a critical factor in the alfalfa production systems because it has a significant impact on maximizing yield and maintaining the forage quality. The objective of this experiment was to determine the proper cutting height according to harvesting time for optimizing nutrient yield and forage nutritive quality of alfalfa grown in alpine regions of Korea. Alfalfa was sown at a seeding rate of 30 kg/ha in August 2018 and harvested at four cuttings in 2019 (3 May, 2 July, 11 September, and 13 October). Cutting heights were adjusted at 5, 15, and 25 cm above the soil surface. Alfalfa plant was tallest at the third cutting (109 cm), which was on average 35 cm taller than the first or second cutting. Relative feed value (RFV) remained unaffected by cutting height at the first harvest, but increased consistently in subsequent harvests as cutting height increased. Alfalfa collected at the first and fourth cuttings had the highest RFV (mean 152), which was on average 8 and 67 units higher than the second and third harvests, respectively. At each harvest, in vitro dry matter digestibility was highest in alfalfa cut at a 25-cm height. Dry matter (DM) production at each cutting height was highest in the first cutting, accounting for on average 36-37% of total annual DM production, and lowest in the fourth harvest, accounting for about 11-13% of the total DM yield. The total dry matter production (in four harvests) was 4,218 kg/ha higher when alfalfa was subjected to a cutting height of 5 cm rather than 25 cm. Cutting height had no effect on total crude protein yield, but from the first to fourth cutting, the protein yield followed a decreasing trend. Finally, there were visible declines in forage nutritive quality when alfalfa was cut at a shorter height. However, the magnitude of difference in total forage yield may outweigh the slight decline in forage quality when alfalfa is cut at a lower height. The findings of this study could help the alfalfa growers make better harvest management decisions.

• Journal of Bio-Environment Control
• /
• v.19 no.4
• /
• pp.392-396
• /
• 2010

This research focused on determining the effectiveness of cluster and/or flower thinning in highbush 'Jersey' blueberry on the yield and fruit quality. The total yield and quality of fruit were compared between thinning methods of control (no thinning), 1/3 cluster thinning, 1/3 cluster thinning + 1/2 flower thinning, 2/3 cluster thinning, and 2/3 cluster thinning + 1/2 flower thinning per each bearing shoot, respectively. Thinning strength significantly affected the yield of bearing shoot and, thus, total yield of control and 1/3 cluster thinning was higher than others. Both cluster and flower thinning, however, significantly affected the fruit growth resulting in the increase of fruit weight, length and width. Even total yield was similar between control and 1/3 cluster thinning, more larger fruit (> 1.6 g) were produced by 1/3 cluster thinning treatment, indicating that flower and/or cluster thinning contributed to the increase of individual fruit growth. Unlike fruit growth, fruit quality was less affected except total soluble solid contents. Total soluble solid level significantly increased in treatments (2/3 cluster thinning, 2/3 cluster thinning + 1/2 flower thinning) with yield decrease. No significant difference in levels of acidity and firmness of fruit was found. Results indicated that fruit growth and total yield of highbush blueberry was more influenced by the thinning strength regardless of cluster or flower than internal quality of fruit such as solid and acid levels.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.40 no.4
• /
• pp.85-93
• /
• 1998

In the 2nd year study of a 5 year project to evaluate the soil quality and develop the best management practices for mountaineous soils, 11 runoff plots were treated and monitored with respect to physical property of the soil, runoff and sediment discharge, and the following results were obtained. 1. Bulk density and porosity did not show any siginificant difference between experimental treatments. 2. Runoff was basically dependent on the soil's physical property and tillage. Up-and-down plots showed the highest runoff while contour plots the lowest runoff. 3. Sediment yield in the mountaineous soils was directly related to tillage and residue cover. Residue covered plots showed the lowest sediment yield and up-and-down plots the highest sediment yield. And it is recommended that the best management practices using till_age and residue cover for the mountaineous soils must be developed to protect soil quality and maintain agricultural productivity.

• Journal of Ginseng Research
• /
• v.22 no.1
• /
• pp.11-17
• /
• 1998

To develop a new ginseng varieties with good quality and high yielding, a lot of individual ginseng plants were selected in the farmer's fields in 1972. Among them, a promising line, 7259-3-1, has been developed through comparative cultivation of several lines selected with pure line separation of local races in Korea Ginseng '||'&'||' Tobacco Research Institute. Preliminary and advanced yield trials were performed for 8 years. It was then designated as "KG 101" and tested in the regional yield and adaptation trials for 10 years (1981-1990). KG101 has a green stem with light violet and orange-yellow fruit and flowers 3-7 days later than local race, Takyungjong. Taproot of KG101 was longer than local race Jakyungjong, and root yield of KG101 was 9% higher than local race Jakyungjong. In red ginseng quality, the rates of Chun-Jeesam (Chun and Jee means 1st and 2nd grade, respectively) were 22.3% and 9.4% for KG101 and Jakyungjong, respectively. In these results, it was clarified that KG101 was superior ginseng line with good quality.y.

• Journal of the Korean Society of Tobacco Science
• /
• v.5 no.2
• /
• pp.3-7
• /
• 1983

Three levels of nitrogen, phosphate and potassium were applied to tobacco for the establishment of the optimum rate of the fertilizers for yield and quality. 1 . The rate increment of nitrogen and potassium increased tobacco growth, but phosphate were non - significant between rate. 2. The contents of total-nitrogen and total-alkaloid in the leaf were increased, with the increase of nitrogen rate while the effect of phosphate and potassium were negligible. 3. The yield and quality of the tobacco were increased with the increasing rate of nitrogen and potassium fertilizer but phosphate should little difference.