• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.1
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• pp.10-14
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• 2013

This experiment was carried out to breed an early maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in the Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan from 2009 to 2011. A new variety, 'Green farm II' is a diploid with green leaves and has a semi-erect growth habit in late autumn and erect growth habit in early spring, respectively. 'Green farm II' was on the $28^{th}$ of April in the heading date as an early-maturing variety. 'Green farm II' was also wider by 0.6 mm in flag leaf width, shorter by 1 cm in flag leaf length and shorter by 1 cm in plant length than those of the control variety, 'Florida 80', respectively. 'Green farm II' was thicker by 0.7 mm in stem thickness and strong in winter hardness. Dry matter (DM) yield (11,452 kg/ha) of 'Green farm II' was similar to that of 'Florida 80'. In vitro dry matter digestibility (IVDMD), total digestible nutrients (TDN), and relative feed value (RFV) of 'Green farm II' were 70.6%, 63.9%, and 114% higher than those of 'Florida 80', respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) of 'Green farm II' were 31.7% and 52.6% which were 3.5% and 6.4% lower than those of 'Florida 80', respectively.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.5 s.112
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• pp.83-93
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• 2005

Research was initiated to investigate turf performance under USGA soil system. USGA system 45 centimeters deep was built with rootzone layer, intermediate layer, and drainage layer. Six turfgrass entries were comprised of 3 blends and 3 mixtures from cool-season grasses (CSG). Turfgrass color and quality ratings were best in spring and fall, especially early May to early July and late August to early November. Kentucky bluegrass (KB) consistently produced the greatest performance, while perennial ryegrass (PR) the poorest. Intermediate turf performance between KB and PR was observed with tall fescue (TF). Among CSG mixtures it increased with KB but decreased with PR. There were considerable variations in summer turf Performance. No summer drought injury was found in KB and TF. However, PR showed poor performance through summer as compared with others. Among mixtures, it decreased with PR. It was suggested that PR mix in less than $20\%$ in the mixtures to have an acceptable quality in summer. Cultural intensity also affected it. With lowering mowing height, KB of rhizomatous-type in growth habit kept good quality, while PR and TF with bunch-type in growth habit poor quality. Mowing quality was greatly different among CSG. KB produced clean-cut surface, but PR unclean one. If had an intermediate mowing quality between KB and PR. A great difference in green color retention was observed among CSG. The longest CSG was PR that kept green for 339 days, while the shortest one TF for 267 days. KB continued to keep green for 290 days. The mixtures kept green in color for 292 to 315 days, depending on turfgrass mixing intensity. The greater the PR in content, the longer the green color duration. These results demonstrate that KB was the best and PR the worst among CSG grown in USGA system under a domestic climate, in regards of turf quality, color, mowing quality, summer turf performance and green color duration. KB and TF are most adequate for high-maintenance and low-maintenance area, respectively. In case of mixtures for high-quality turf, it was desirable to use KB-based mixture with PR of below $20\%$ in seeding rate.

• Journal of the Korean Society of Tobacco Science
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• v.16 no.1
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• pp.76-83
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• 1994

The dominant colour - types of fundatrices of green peach aphid, Myzsts persicae 5. were yellow - green, red and green. Yellow type was the minority among nymphs produced by field collected alatae. Rate of producing dead nymphs was over 34.0% in red and yellow types apterae grown from tobacco plants in early summer. Brown and green were the dominant colour - type in apterae throughout tobacco growing season. Brown type on tobacco, and yellow type on hot pepper and tomato grew better and produced more nymphs than other colour - types.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.4
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• pp.135-141
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• 2015

The objective of this study is to develop an early warning system for rainfall induced landslides. For this study, we suggested an analysis process using rainfall forecast data. 1) For a selected slope, safety factor with saturated depth was analyzed and safety factor threshold was established (warning FS threshold=1.3, alarm FS threshold=1.1). 2) If rainfall started, saturated depth and safety factor was calculated with rainfall forecast data, 3) And every hour after safety factor is compared with threshold, then warning or alarm can issued. In the future, we plan to make a early warning system combined with the in-situ inclinometer sensors.

• Journal of The Korean Society of Grassland and Forage Science
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• v.27 no.4
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• pp.257-262
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• 2007

The objective of this research was to develop a high yielding, early and medium-late flowering new hairy vetch(Vicia villosa Roth) varieties derived from an accession in Korea. Most vigorous early and medium-late flowering hairy vetch lines were selected and crossed by open pollination and their seeds were bulked and plants were reselected at Seongju in the Keongbuk and at Sacheon in the Keongnam. A performance trial was conducted to evaluate agronomic characteristics, forage quality and dry matter(DM) yield of new hairy vetch early-maturing 'Cold green' and medium-late maturing variety 'Cheong pa' at Seongju and Sacheon. 'Cold green' and 'Cheong pa' are hair but 'Haymaker plus' and 'Latigo' are nearly hairless. 'Cold green' has purple flowers while 'Cheong pa' has violet. The cold tolerance of 'Cold green,' 'Cheong pa' and 'Latigo' was higher than 'Haymaker plus' at Seong-ju, Keongbuk province, in inland region but there were a little differences at Sacheon, Keongnam province in southern coast region. Fifty percent-flowering dates of 'Cold green' and 'Haymaker plus' had earlier than others and 'Cheong pa' was earlier than 'Latigo'. The DM yield of 'Cold green' was higher than that of others, but 'Cheong pa' and 'Haymaker plus' had higher than 'Latigo' at Seong-ju(P<0.05). In Sacheon, The DM yield of 'Cold green' and 'Haymaker plus' was higher than others and 'Cheong pa' had higher than 'Latigo'.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.243-250
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• 2011

This experiment was conducted to evaluate agronomic characteristics, forage quality and dry matter (DM) yield of early-maturing hairy vetch 'Cold green', 'Haymaker plus', 'Cappello' and medium-late maturing cultivar 'Cheong pa', 'Challenger', 'Hungvillosa' and 'Latigo' at Seongju in the Kyeongbuk from 2009 to 2011. The experiment was arranged in randomized complete block design with three replications. Hairy vetchs were seeded on Sep. 26 and Oct. 11 in 2009 and 2010. Vetch plants were harvested on 30 Apr. in 2010 and 2011. Cold tolerance for Haymaker plus and Cappello were a little lower than other cultivars. Fifty percent-flowering dates of Cold green had earlier than others and Haymaker plus and Cappello were earlier than Cheong pa, Challenger, Hungvillosa and Latigo. Cheong pa and Challenger were ealirer than Hungvillosa and Latigo. The DM yield of Cold green was the highest (p<0.05) of the cultivar except Haymaker plus. Haymaker plus was higher (p<0.05) than others and Cappello, Cheong pa, Challenger were higher (p<0.05) than Hungvillosa and Latigo in 2010. In 2011, the DM yield of Cold green was the highest (p<0.05) of the cultivar and Haymaker plus was higher (p<0.05) than others. Cappello was higher (p<0.05) than Hungvillosa and Latigo. Cheong pa and Challenger were higher (p<0.05) than Latigo. Vetch cultivar was high in crude protein (CP) and low in Acid detergent fiber (ADF). According to the results obtained from this study, it is suggested that early-maturing cultivar would be recommendable for fall sown vetch for DM production.

• Weed & Turfgrass Science
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• v.4 no.4
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• pp.383-389
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• 2015

The use of zoysiagrass (Zoysia japonica Steud.) in the transition zone is limited because of a lack of cold hardiness although zoysiagrass has many advantages compared to other warm-season and cool-season grasses. Late-fall N fertilization is often applied for darker green color of turfgrass in early spring and more extensive root growth without rapid top growth. The objective of the study was to evaluate the effects of late fall N application and turf cover for zoysiagrass spring green-up. Clear polyvinyl chloride (PVC) film was used for turf cover. The amount of N applied were 5 and $10g\;N\;m^{-2}$ for the low and high N rate treatments, respectively. Covered zoysiagrass had greater turfgrass color and quality in early spring than non-covered zoysiagrass. The high N rate had 0.6 to 2.3 greater turfgrass quality than the low N rate on 7 of 9 rating dates. Slow-release N as late fall fertilization is more effective for turfgrass color and quality than fast-release N in spring. Turf cover could reduce the period of yellow zoysiagrass, and the earlier time of spring green-up could be advanced by increasing turfgrass quality and growth of zoysiagrass.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.342-353
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• 2016

This study was initiated to evaluate green color retention under three different soil systems. Several turfgrasses were evaluated in multi-layer, USGA, and mono-layer systems. Turfgrass entries were comprised of three cultivars of Korean lawngrass (Zoysia japonica Steud.) as warm-season grass (WSG) and three blends and three mixtures of Kentucky bluegrass (KB, Poa pratensis L.), perennial ryegrass (PR, Lolium perenne L.), and tall fescue (TF, Festuca arundinacea Schreb.) as cool-season grass (CSG). Significant differences were observed in visual turf color and green color retention among soil systems and turfgrasses. Both the multi-layer and USGA systems were highly associated with better color ratings and longer color retention, as compared with the mono-layer system. Seasonal variation of visual turf color greatly occurred from late December to early spring. CSG exhibited longer color retention than did WSG. The latter maintained green color for approximately 6 months, regardless of the soil system. Spring green-up of Korean lawngrass occurred from early to middle May, while it underwent discoloration from late October to early November. Among the CSGs green-up occurred between early March and early April and leaf color was maintained until middle December to early February. Therefore, the CSGs were green for 8.5 to 11 months, depending on turfgrass and soil system. The mean period of green color duration across all soil systems was approximately 10-11, 9-10 and 8.5-9.0 months for PR, KB and TF, respectively. As for the CSG mixtures, the greater the proportion of PR, the longer the green color retention, while the higher the proportion of TF, the shorter the color retention. There was greater variation in green color duration among the CSGs than the WSGs. Across soil systems, color retention differences of 2 to 6 days were observed for the Korean lawngrass, but 7 to 36 days for the CSGs. These results demonstrate that green color retention varied greatly according to soil systems and also among turfgrasses. Selections of turfgrass and soil system should be made using a concept-oriented approach, when establishing garden, park, soccer field, golf course and other sports field. Information obtained in this study can be used to select soil systems and turfgrasses based on the expected degree of leaf color retention.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.4
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• pp.247-252
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• 2018

This experiment was carried out to breed a very early maturing variety of Italian ryegrass (Lolium multiflorum Lam.) in Grassland and Forage Crops Division, National Institute of Animal Science, RDA, Cheonan from 2015 to 2017. New variety of Ryegrass, 'Green Call' is a diploid variety with green in leaf color and has semi-erect growth habit in late autumn and erect growth habit in early spring, 'Green Call' was on April 25 in heading date as a early-maturing variety. Also 'Green Call' was narrower by 2 mm in flag leaf width, longer by 1.3 cm in flag leaf length and shorter by 5 cm in plant height than those of control variety, 'Florida 80', respectively. 'Green Call' was also thicker by 0.14 mm in stem thickness and strong in winter hardness. Dry matter (DM) yield (11,592 kg/ha) of 'Green Call' was similar to that of 'Florida 80'. Total digestible nutrient (TDN), crude protein (CP) and relative feed value (RFV) of 'Green Call' were 60.8, 10.3 and 96.7 % which are 2.1, 1.1, 6.9 % higher than those of 'Florida 80', respectively. Acid detergent fiber (ADF) and neutral detergent fiber (NDF) of 'Green Call' were 35.5 and 58.9 % which are 2.7 and 2.3 % lower than those of 'Florida 80', respectively.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.3
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• pp.110-119
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• 2017

This study develops a passive traffic signal priority control algorithm for emergency vehicles. The passive priority control estimates and applies signal times for each signalized intersection on the emergency vehicle's route when an emergency call is received. As signals are controlled before the emergency vehicle leaves for its destination, it is possible to clear the queues at each intersection more effectively. Most of the previous studies applied preemption, which ends green time of cross streets when the emergency vehicle arrives at each intersection. This study applies green extension and early green in order not to shift the order of phases, and guarantees minimum green time for each phase. Simulation results show that the delay of emergency vehicles decreases when the signals are controlled. It is expected that delays can be decreased further by integrating the active priority control with the passive priority control algorithm presented in this study.