• Journal of Korean Society of Coastal and Ocean Engineers
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• v.33 no.4
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• pp.168-178
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• 2021

Numerical simulations were implemented to look into the modified seabed topography due to the presence of breakwaters of varying reflection characteristics. The numerical model was composed of OlaFlow, an OpenFoam-based tool box, and a physics-based morphology model [Seoul Foam]. In doing so, the interaction between the seabed, which undergoes deformation due to siltation and scouring, and the incoming waves was described using Dynamic Mesh. The rubble-mound, vertical, and curved slit caisson breakwaters with varying reflection characteristics resulted in standing waves that differ from each other, shown to have a significant influence on the seabed topography. These results are in line with Nielsen's study (1993) that sands saltated under the surface nodes of standing waves, where the near-bed velocities are most substantial, convected toward the surface antinodes by boundary-layer drift. Moreover, the crest of sand waves was formed under the surface antinodes of standing waves, and the trough of sand waves was formed under the surface antinodes. In addition, sand wave amplitude reaches its peak in the curved slit caisson with a significant reflection coefficient, and the saltation of many grains of sand would cause this phenomenon due to the increased near-bed velocity under the nodes when the reflection coefficient is getting large.

• Korean Journal of Plant Taxonomy
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• v.43 no.1
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• pp.56-62
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• 2013

Echinochloa oryzoides (Ard.) Fritsch (Na-do-non-pee), was found at paddy fields of Jeonranamdo on a large scale after a first discovery at Masan, Kyeongsangnamdo. This species was not easily distinguished from rice before flowering at the paddy field because of a similar morphology to rice. It is, however, distinguished from other species of the Korean Echinochloa by reliable morphological characters such as horizontal or drooping panicles at maturity, lower glumes with usually 1/4-2/5 as long as the spikelets, awned lower lemmas, and the number of chromosomes, 2n = 54. Echinochloa oryzicola (Vasinger) Vasinger was distinguished from E. oryzoides by erect panicles, lower glumes with at least 1/2 as long as the spikelets, and the number of chromosomes, 2n = 36.

• The korean journal of orthodontics
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• v.25 no.1 s.48
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• pp.73-85
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• 1995

Multi-Vertical Loop Arch Wire(MVLAW) is a kind of appliance for uprighting the mesially inclined posterior teeth axes simultaneously. In this study MVLAW was classified as 3 types by modifing the vertical loop design and named type A, B and C. Each MVLAW was fabricated from .017'x.025' TMA wire and preactivated at the distal end of the open vertical loop with 10 degree tip-back bend(type B has an electric welding stop at the distal end of each loop and type C has no electric welding stop). Type A MVLAW was preactivated at the apex of each open vertical loop with 10 degree tip-back bend(the electric welding stop of type A is positionod at the mesial side of each loop). The aim of the present study was to identify when and which MVLAW is more effective to correct the buccal segment axes simultaneously. The Photoelastic overview of the upper and lower right quadrant showed that stress concentrations were observed in its photoelastic model. The obtained results were as follows : 1. Higher level compression can be seen clearly at the distal curvature of the lower 1st and 2nd molar when A type MVLAW was applied without short class m elastic, but mild compression cannot be seen at the distal curvature of lower anterior teeth using the class m elastic. 2. Higher concentration was presented at the mesial curvature from the lower 1st premolar to the 2nd molar than the anterior teeth when B type MVLAW without short class III elastic was applied, but using the short class III elastic, higher concentration of compression was presented in the anterior teeth area. 3. Areas of higher compression and tension were not observed at the mesial and distal curvature of the entire 1ower teeth except lower central and lateral incisors in C type MVLAW without short class III elastic, but using the short class III elastic, higher concentration was seen at the mesial curvature of the lower 1st premolar and 1ower anterior teeth.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.194-197
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• 2005

This experiment was conducted to investigate the effect of turf growth characteristics to different transplanting times. It observed that the turf growth was decreased according to delaying the transplanting time. In respect to the turf growth characteristics, it appeared that there was good for transplanting time to transplant the turf seedling before early July. With sustaining the short day length after early July, it shown that number of branch on stolen, number of nodes and Total length of stolen were apparently decreased. Especially, number of branch on stolon was decreased from 2nd up-growing branch.

• Korean Journal of Weed Science
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• v.7 no.1
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• pp.58-63
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• 1987

Laboratory and greenhouse studies were conducted to evaluate effects of spray volumes and surfactants, L-77 and Triton CS-7 on leaf retention of glyphosate in Zea mays, Hordeum vulgare, Artemisia princeps, Trifolium repens and Equisetum arvense. Leaf retention was increased when glyphosate with L-77 or Triton CS-7 was applied in a spray volumes of 10-20 l/10a in Zea mays and 40 l/10a in Artemisia princeps but decreased when spray volumes were higher than above volumes and 40-80 l/10a in Trifolium repens. Hordeum vulgare leaves retained more spray when glyphosate with L-77 or Triton CS-7 was applied in all spray volumes tested. Equisetum arvense retained higher amount of spray by application of glyphosate with L-77 compared with Triton CS-7 and no surfactant treatments.

• Korean Journal of Plant Resources
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• v.16 no.2
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• pp.147-154
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• 2003

Agronomic characters of the 361 Korean adzuki beans(Vigna angularis (Willd.) Ohwi & Ohashi) collected in Korea were examined. Korean adzuki beans had predominantly up right growth habit types, followed by the intermediate types (15.3%) and the climbing types (6.9%). Round leaf type was the majority among the collections and followed by elliptical and xiphoid leaf type. Adzuki beans with yellow, light yellow and dark yellow flowers were 89.5％, 9.4％ and 1.1％, respectively. The 60.6% of the collections had red seeds and 26.9% had gray seeds. And collections with green seeds, white seeds mixed with gray spot, brown spots on red seeds, black spots on red seeds and dark gray spots on black seeds were also observed. Korean adzuki beans whose number of days from planting to flowering were 69∼75 days were the majority among 361 Korean adzuki beans. The number of days from flowering to majority were 41∼50 days and the number of days from planting to maturity were 111-120days. Adzuki beans having the stem length of 41-60 cm, the pod number per plant of 16-20 and the 100 seed weight of 8∼10 g were 50.2％, 40.2% and 30.5％ of collections, respectively.

• The korean journal of orthodontics
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• v.25 no.1 s.48
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• pp.111-128
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• 1995

This study was investigated to assess the difference of facial height and occlusal plane inclination between pre- and post-treatment in Class I malocclusion group The subjects consisted of 35 extraction patients and 30 nonextraction patient,;, and was subdivided into Group I(overbite<0mm), Group II(04mm) in reference to overbite, and adolescent group and adult group in reference to age. Lateral cephalogram was taken with standard method, traced, and digitized for each subject. The computerized statistical analysis was carried out with SAS program The results wolf as follows. 1. In both groups of extraction and nonextraction group the anterior facial height increased after orthodontic treatment but there was no significant difference(p>0.05) between each goup. 2. There was no statstical significance in change of occlusal plane inclination in adolescent group, but significant difference(p<0.05) among three subgroup in adult group. 3. In adolescent-extraction and adolescent-nonextraction group there was significant increase of anterior facial height and posterior facial height, and was superior to adult groups in posterior facial height increment. 4 In all groups upper and lower molars were uprighted to occlusal plane. This had statistically significant effect.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.23 no.3
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• pp.258-264
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• 2011

A MCS technique is represented to stochastically analyze the uncertainties of wave forces exerted on the upright sections of composite breakwaters. A stochastical models for horizontal and uplift wave forces can be straightforwardly formulated as a function of the probabilistic characteristics of maximum wave height. Under the assumption of wave forces followed by extreme distribution, the behaviors of relative wave forces to Goda's wave forces are studied by the MCS technique. Double-truncated normal distribution is applied to take the effects of uncertainties of scale and shape parameters of extreme distribution into account properly. Averages and variances of relative wave forces are quantitatively calculated with respect to the exceedance probabilities of maximum design wave height. It is found that the averages of relative wave forces may be decreased consistently with the increases of the exceedance probabilities. In particular, the averages on uplift wave force are evaluated slightly larger than those on horizontal wave force, but the variations of coefficient of the former are adversely smaller than those of the latter. It means that the uncertainties of uplift wave forces are smaller than those of horizontal wave forces in the same condition of the exceedance probabilities. Therefore, the present results could be useful to the reliability based-design method that require the statistical properties about the uncertainties of wave forces.

• Korean Journal of Breeding Science
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• v.49 no.3
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• pp.230-234
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• 2017

A mungbean variety 'Suhyeon' (Vigna radiata (L.) Wilczek) was derived from the cross between 'Jeonnam14' and 'IT208777' at the Jeollanamdo Agricultural Research and Extension Services (JARES) in 2010. 'Suhyeon' has erect growth habit, heart leaflet, green hypocotyl, black and straight pod when matured, and dull green seed surface. The stem length of 'Suhyeon' was 66 cm, which was 5 cm less than check variety 'Owool'. The pods number per plant of 'Suhyeon' was 24, which was 5 more than check variety. The sprout yield ratio of 'Suhyeon' was 8.67 times, which was 16% more than check variety. The contents of starch, protein and fatty acid of seed were 62.7, 27.3, 1.89%, respectively. The average yield of 'Suhyeon' was 1.74 ton/㏊, which increased 8% more than that of check variety. (Variety registration number: 5107)

• Korean Journal of Weed Science
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• v.9 no.2
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• pp.141-148
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• 1989

Echinochloa species collected from 13 places of Korea appeared to be morphologically very different. They were classified by Yabuno's seed morphology method into two species such as Echinochloa oryzicola and Echinochloa crus-galli which have two varieties such E. crus-galli var, cuss-galli and var, praticola. Among them, E. oryzicola was morphologically similar to Oryza sativa, but it had small leaf length with straight from, no awn, late heading and little interspecific variance. As compared with E. oryzicola, E. eras-galli var. crus-galli, and var, praticola showed a great variance exerting so difficulty in classifing them morphologically, particularly a great variance in leaf length, tiller number and grain size. E. oryzicola species showed the more sensitive response to butachor and thiobencarb herbicides than E. eras-galli var. praticola and var. eras-galli. However, E. eras-galli var. praticola was themore sensitive one to pretilachloa herbicide than such as E. oryzicola and E. eras-galli var. eras-galli, indicating that Echinochloa species might have a selective response to the annual herbicides tested.