• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.276-283
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• 2023

Garlic (Allium sativum L.) is one of the most important vegetables used in various foods in Korea and many countries. The growth of garlic is influenced by various abiotic factors such as cultivation temperature, humidity, minimum temperature duration, and photoperiod. This study investigated the effects of increasing temperatures on the plant growth of the northern- ecotype garlic 'Uiseong' in a temperature gradient tunnel. As a result, temperature increase led to decreases in the bulb diameter, weight, and clove pieces of garlic. The rise of cultivation temperature increased the occurrence rate of incomplete bolting in the Northern-ecotype garlic 'Uiseong', resulting in decreases in productivity and a decrease in the yield of marketable garlic, indicating that temperature increases affect the development of garlic bulb formation. The findings of this study are expected to contribute as foundational data for understanding the growth responses of the northern-ecotype 'Uiseong' to increasing cultivation temperatures. The results of this study can be used to develop designing garlic growth models. In addition, the results of this study can improve understanding the interaction between increased temperature and garlic growth.

• The Korean Journal of Ecology
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• v.14 no.2
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• pp.211-230
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• 1991

The germinatin of e. annuus continued from the middle ofmay to mid-october. The maximum germination occurred on the mid-july. The period bloom of was distingushed amongs the different growth forms ; a orm pr of biennial and a form of pr perennial flowering from the mid-may to mid-september, and a form ps biennial blossom from the beginning of October to earlynovember. the dispersal of seed for(a form pr)occurred from early June to the mid-september. A rotte, germinating from summer to autumn, could classified into several growth forms; individuals without a critical leaf area for bolting until september and October, become a form ps of biennial, whicth did not proceed toreproductive growth unitl the next year, even thought wintering. individuals flowered on 3 years after germination become a form pr of perennial. The growth formular of aform pr of bennial, grown in a pot was w=20.2[1+$3.36{\times}10^3$(-0.062t)]$^{-1}$. The maximum relative growth rate(rgr) was 0.062g/g/day and the maximum net assimlation rate(nar) 0.089g/g/day. Therelative growth among each organ was shown as R=0.12 $T^{1.15}$between the avove-ground part(t) and the below- ground part(r). the relation between the avove-ground part(t) and the ratio of stem weight(wi) was ws/wi=2.56 $T^{0.35}$. n.p.k. was largely distributed on a leaf throughoutthe total growth period. while growing, it tended to decrease on the vegetative organ gut vice versa on the reproductive organ. however, nitrogen was more widely distributed on a leaf then in the reproductive organ.

• Korean Journal of Plant Resources
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• v.9 no.2
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• pp.197-201
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• 1996

To greatly decrease bolting rate and deterioration of root quality, seeds of Angelica gigas had sown and grown several month earlier than traditional seedtime. Roots were harvested in the middle of November in same year. Roots were devided to several parts such a fune root, secondary root, stele and cortex of main root. We ditermined and compared with the major constisuents contained in each parts of 1 and 2 year old roots. Among each parts of root, the amount of constituents in the fine root and cortex were much higher than those in stele of main root. Content of decursin and decursinol angelate was higher 6.5% in 2 year old root than 4.8% in 1 year old root and their component ratio showed 10:7.5 in 1 year old root and 10:6.0 in 2 year old root, respectively. But merits as a material of oriental medicine for 1 year old root that cultivated by early short-time growing seedling were generally acknowledged.

• Korean Journal of Medicinal Crop Science
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• v.13 no.3
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• pp.109-113
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• 2005

To analyze the genetic relationship 8 accessions of Ostericum koreanum Kitakawa, random amplified polymorphic DNA(RAPD) analysis was performed using 60 Operon primers. The 25 primers out of 60 random primers were amplified DNA by PCR using genomic DNA of O. koreanum. Eighty-five (49.1%) among 173 bands derived from 25 primers showed poly morphism, On the basis of similarity coefficient analysis by UPGMA, 8 accessions of O. koreanum Kitakawa could be classified into three groups at the similarity coefficient value of 0.71. Group I contained three accessions (Nam Gangwhal), Group II contained one accession (Nam Gangwhal) and Group III contained four accessions (Buk Gangwhal), The range of total genetic similarity coefficient value of 8 accessions of O. koreanum Kitakawa was $0.63{\sim}0.96$. Buk Gangwhal was flowered 18 to 26 days earlier than Nam Gangwhal, and Nam Gangwhal leaf stalk was thin and long as bolting rate high compared with Buk Gangwhal.

• Korean Journal of Plant Resources
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• v.13 no.1
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• pp.11-17
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• 2000

In an effort to produce high quality Angelica gigas in the southern area of Korea, a variety of mulching materials were used to prevent withering during the summer. The experimental results are summarized as follows. Soil water content and temperature under various mulching materials were higher than those without mulching, in all the cases studied. Among various mulching materials P. E.(polyethylene) mulching material showed the highest effect. The appearance of weeds was the lowest when using the black P. E. mulching, while growth of weeds was the greatest when using transparent mulching. Growth and development of the plant were better with P. E. mulching than straw mulching or no mulching, allowed for more and bigger leaves. The bolting rate was about 2∼5%, with a slightly larger value under P. E. mulching. Under P. E. mulching, probably due to good physical properties of the soil the number of roots was large, and the length and diameter were good. Active growth of roots under P. E. mulching resulted in a yield increase of the plant. The black P. E. mulching material showed a prominent effect on suppression of weed growth, and the black P. E. material was considered to be the most recommendable among various P. E. mulching materials when there is a lack of labor.

• Tribology and Lubricants
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• v.32 no.4
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• pp.132-139
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• 2016

The piston of a marine diesel engine works under severe conditions, including a combustion pressure of over 180 bar, high thermal load, and high speed. Therefore, the analyses of the fatigue strength, thermal load, clamping (bolting) system and lubrication performance are important in achieving a robust piston design. Designing the surface profile and the skirt ovality carefully is important to prevent severe wear and reduce frictional loss for engine efficiency. This study performs flexible multi-body dynamic and elasto-hydrodynamic (EHD) analyses using AVL/EXCITE/PU are performed to evaluate tribological characteristics. The numerical techniques employed to perform the EHD analysis are as follows: (1) averaged Reynolds equation considering the surface roughness; (2) Greenwood_Tripp model considering the solid_to_solid contact using the statistical values of the summit roughness; and (3) flow factor considering the surface topology. This study also compares two cases of skirt shapes with minimum oil film thickness, peak oil film pressure, asperity contact pressure, wear rate using the Archard model and friction power loss (i.e., frictional loss mean effective pressure (FMEP)). Accordingly, the study compares the calculated wear pattern with the field test result of the piston operating for 12,000h to verify the quantitative integrity of the numerical analysis. The results show that the selected profile and the piston skirt ovality reduce friction power loss and peak oil film pressure by 7% and 57%, respectively. They also increase the minimum oil film thickness by 34%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.3
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• pp.254-258
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• 1991

Experiment was conducted to investigate the effects of size of root crown at transplanting and fertilization on the growth and root yield of Angelica gigas Nakai. Plant height and fresh weight of shoots were increased by fertilizer application, but was not different in emergence rate. Size of root crown at transplanting was also affected the growth of shoot. Plant which had 7.2mm of root crown at transplanting showed highest in plant height and fresh weight of shoots. Growth of root in terms of root length, number of root branches, diameter of root crown, and fresh weight of root was increased by fertilizer application and 5.4mm of root crown at transplanting. Application of fertilizer accelerated the development and growth of node on the stem, which in turn resulted bolting and flowering. Plants which had greater than 7.2mm of root crown at transplanting and application of fertilizer were produced woody roots. Woody roots cannot be used for medicinal purpose. Therefore, yield of roots was highest at transplanting of 3.lmm root crown with fertilizer application.

• Korean Journal of Plant Resources
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• v.25 no.5
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• pp.586-590
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• 2012

This study was conducted to investigate the seedling cultivation methods of Ostericum praeteritum Kitag. The results are as follows ; Ostericum praeteritum transplanted from wild seedlings and seedling cultured in the open field grew quite well, but their bolting rate was higher than other seedlings resulting in low root production. Seedling cultured in tray pot of green house produced good quality root as 426 kg/10a indicating the most adequate seedling method for Ostericum praeteritum production. Main compounds of Ostericum praeteritum roots were found as oxypeucedanin and bisabolangelone, and contents of wild seedlings were lower than theirs of the other seedlings methods.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.587-590
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• 2009

New onion hybrid cultivar, "Yeongpunghwang" was developed from cross between "MOS8", male sterile line and "Mokpo 11", pollen line by Mokpo Sub-Station, National Institute of Horticultural & Herbal Science, RDA in 2008. The crossing line was performed yield test in 2003. IT was evaluated as "Mokpo 11" in the regional yield trial test(RYT) from 2006 to 2008 during three years. This line is semi-erect plant growth type and has green leaf colour. It has broad ovate bulb shape and yellow skin colour in bulb characteristics. Plant height, leaf number, and bolting rate was 78cm, 7.9, and 3.9%, respectively. Lodging date as harvesting indicator was on 26 May. The yield potential of "Yeongpunghwang" was out-yielding 6% compare to check variety ("Sunpower") by with 8,344 kg/10a in RYT. It showed moderated cold hardness in all regional location which was conducting RYT, including Muan, Goheung, Changyeong and Andong. So this variety was recommend as a leading variety at southern area of korea.

• Korean Journal of Plant Resources
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• v.13 no.2
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• pp.124-130
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• 2000

In an effort to produce high quality Angelica gigas NAKAI in the southern area of Korea, a variety of mulching materials were used to prevent withering during the summer. The experimental results are summarized as follows. Soil water content and temperature under various mulching materials were higher than those without mulching, in all the cases studied. Among various mulching materials P. E.(polyethylene) mulching material showed the highest effect. The appearance of weeds was the lowest when using the black P. E. mulching, while growth of weeds was the greatest when using transparent mulching. Growth and development of the plant were better with P. E. mulching than straw mulching or no mulching, allowed for more and bigger leaves. The bolting rate was about 2∼5%, with a slightly larger value under P. E. mulching. Under P. E. mulching, probably due to good physical properties of the soil the number of roots was large, and the length and diameter were good. Active growth of roots under P. E. mulching resulted in a yield increase of the plant. The black P. E. mulching material showed a prominent effect on suppression of weed growth, and the black P. E. material was considered to be the most recommendable among various P. E. mulching materials when there is a lack of labor.