• Journal of the Korean Geotechnical Society
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• v.36 no.12
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• pp.69-76
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• 2020

Since the mechanically stabilized earth walls have a form of retaining wall compatible with a narrow section, the geogrid overlaps according to the separation distance between the walls. There is a problem that the overall behavior may occur in the state of being integrated with the stress change due to the interaction of the geogrid. Therefore, a careful approach is required at the design stage, but there are currently no design criteria or guidelines in Korea. This study investigated the optimal reinforcement length ratio according to the retaining wall width to height ratio (width to height ratio, Wb/H) for these back-to-back mechanically stabilized earth walls. Retaining wall width ratio is 1.1H, 1.4H, 1.7H, 2.0H for Case II of the FHWA design standard, and the height is 3.0 m, 5.0 m, 7.0 m, and 10.0 m, which are most commonly applied. Through numerical analysis, the appropriateness of the FHWA design standard and the optimal reinforcement length ratio according to the height of the retaining wall and the width of the retaining wall were proposed.

• Journal of Plant Biology
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• v.33 no.1
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• pp.65-72
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• 1990

An anatomical study was conducted in order to elucidate the development of primary and secondary ray in Robinia pseudoacacia L. The height of primary ray near pith decreases progressively toward periphery, while the width and number per unit area gradually increase, and then the height, width and number remain somewhat constant. Secondary ray originates from the segmentation of fusiform initials or division of the side or end of fusiform initials at the middle of the first growth layer. And after the height and width of secondary ray increases to some extent, it remains constantly.

• Journal of the Korean Society of Tobacco Science
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• v.9 no.2
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• pp.37-47
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• 1987

This experiment was conducted to obtain basic information on breeding of flue-cured tabacco varieties . Nine cultivars and partial diallel set of 36 Fl hybrids were grown at Daegu Experiment Station, Korea Ginseng & Tobacco Research Institute in 1983. Partial dominance with high additive gene effect was observed for yield, leaves per plant , days to flower, leaf weight, nicotine and reducing sugar content. partial dominance with additive and dominant gene effect was observed for stalk height , leaf width midrib weight Overdominance with high dominant gene effect was observed for leaf length and midrib width. The directions of dominance were positive for yield, stalk height, leaf weight, leaf length, leaf width, midrib weight, midrib width and reducing sugar content, and the negative was days to flower. The estimates of effective genes were 1 for leaves per plant, 2 for stalk height, days to flower and leaf shape. 3 to 6 for leaf length, leaf width, leaf weight and midrib weight.

• Journal of Biosystems Engineering
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• v.42 no.4
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• pp.258-264
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• 2017

Purpose: This study determines the spray characteristics and effective spray width of a tractor-mounted commercial boom sprayer through experiments. Methods: Performance tests were conducted to investigate the spray characteristics of the nozzles on a commercial boom sprayer. The flow rate and spray width of a single nozzle were measured at three levels of spray pressure (0.5, 0.7, and 1.0 MPa) and spray height (15, 30, and 45 cm), respectively. The average value of three repetition tests was used as the representative value. A coefficient of variation (CV) was used as an index of spray uniformity, and the width that guarantees CV values of approximately 15% was determined as the effective spray width. The spray characteristics of the overall boom sprayer were derived analytically by superimposing the spray characteristics of a single nozzle. Results: The test results for a single nozzle showed that the spray width tended to increase as the spray height and spray pressure increased. The effective spray width for a single nozzle was the largest at a spray pressure of 1.0 MPa and spray height of 45 cm, which resulted in a coverage of 84 cm of width. The effective spray width for the entire boom sprayer was also the largest at the spray pressure of 1.0 MPa and spray height of 45 cm, with a magnitude of 424.5 cm. The chemical spraying work in an actual field was simulated by applying a spray width of 400 cm. As a result of the operation for three swaths, the CV value was less than 10% for 1,200 cm of the overall spray width, which meant that uniform application was achieved. Conclusions: It was reasonable to set the effective spray width of the boom sprayer used in this study to 400 cm.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.2
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• pp.126-132
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• 1992

This experiment was conducted to examine estimates of heterosis, degree of dominance, heritability and phenotypic and genotypic correlation for several mutant characters in flue-cured tobacco variety. Significant heterosis was noted, recording 2.73 and 6.16% for leaf width, -6.86 and -4.72 for leaf shape index, 19.8 and 23.4% for bacterial wilt disease index in Fl an4 F2 generation, respectively, and -1.44 for days to flower in F2 generation. And also leaf width was appeared partial dominance in Fl, and leaf shape index in Fl and F2, Leaf width in F2 was appeared overdominance. Estimated heritabilities in the broad sense ranged from 0.77 to 0.87 for plant and stalk height and days to flower, while those of leaf number, leaf length and width, leaf shape index and bacterial wilt disease index ranged from 0.50 to 0.65. And the heritabilities in the narrow sense were appeared 0.64 and 0.72 for stalk and plant height, respectively, and the others were ranged from 0.32 to 0.47 Positive genotpic correlations appeared among plant height, stalk height, leaf length and leaf width, and between leaf shape index ands day to flower. And negative genotypic correlations appeared between leaf shape index and plant height and stalk height and leaf width, and between bacterial wilt disease index and leaf length.

• The KSFM Journal of Fluid Machinery
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• v.18 no.3
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• pp.66-73
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• 2015

This paper deals with a parametric study on boot-shaped ribs in a rectangular cooling channel. Numerical analysis of the flow and heat transfer was performed using three-dimensional Reynolds averaged Navier-Stokes equations with the Speziale, Sarkar and Gatski turbulence model. The parametric study was performed for the parameters, tip width-to rib width, tip height-to-rib height, rib height-to-channel height, and rib height-to-width ratios. To assess the cooling performance and friction loss, Numsselt number and friction factor were defined as the performance parameter, respectively. The results showed that the cooling performance and friction loss were seriously affected by the four geometric parameters.

• Journal of Life Science
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• v.8 no.4
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• pp.431-436
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• 1998

These studies were carried out to obtain useful information about the effective selection of vegetable perilla by estimating the genetic relationships between the heritabilities and the genetic correlations of quantitative traits among eight agronomic characters from 91 perilla varieties. The positive correlations were showed among characters such as between leaf weight and leaf size, leaf weight and leaf length, leaf weight and leaf width, leaf weight and plant height, leaf weight and stem diameter, leaf size and leaf length, leaf size and leaf width, leaf size and plant height, leaf size and stem diameter , leaf length and leaf width, leaf length and plant height, leaf length and stem diameter, leaf width and plant height, leaf width and stem diameter, plant height and stem diameter, plant height and the number of internodes per plant, and the number of internodes per plant and the number of leaves per plant. Heritabilities were high as from 0.7311 to 0.9112 among leaf weight, leaf size, leaf length, leaf width, plant height, stem diameter, and the number of internodes per plant.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.831-836
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• 1989

It was found that the effect of the friction between the roll and the workpiece on the spread ratio in flat rolling processes varies with the width-to-height ratio and the reduction in height by Tozawa, Oh and kobayashi numerically. In the present study, the barrelling profile accompanying the width spread was predicted by using the energy method proposed by Kato, which is known to be one of the most advanced method for the three dimensional analysis of the rolling process. The modified velocity field was applied to compute the width spread and the result was verified by experiments. the analysis by the energy method gave the result that the spread ratio increases with the friction factor when the width-to-height ratio is 1 and decreases when the ratio is larger then 2, being consistent with the results of Tozawa and Oh. Nevertheless the cold rolling experiment for pure aluminium showed that the spread ratio decreases with the increasing friction factor irrespective of the width-to-hight ratio.

• Journal of Fashion Business
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• v.19 no.3
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• pp.1-13
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• 2015

The purpose of this research is to analyze the morphological relationship between changes hair styles and changes in necklines and collars in 20th century fashion. After selecting the representative plate by each age for this study, the neckline, collar, and formative relevancy of hair style according to it have been analyzed by measuring the neckline, collar, and the width and height item of each hair style. The results of this study show- that the width changes of necklines and collars were mostly proportional in relation to each other, but the width changes of collars and hair styles were inversely proportional. While the amplitude of necklines and collars' width change was very broad, the amplitude of some hair style's height change was very broad. Regarding width, this result had similar results of the researcher's former research, the relation according to the width of necklines, collars and hair style from 16th century to 19th century. However, regarding height, this result was different from the preceding research in that the amplitude of hair style and collars' height change was very broad between 16th and 19th centuries, but the amplitude of neckline's height change is relatively small. This means various heights of necklines appeared in the 20th century, but more various heights of collars were shown between the 16th and 19th centuries. This research hopes to be helpful by predicting trends in fashion, and to be basic resources to understand the systemic relationship of these factors.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.405-410
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• 2001

To investigate factors influencing the effective width of. SRC column-steel beam joint resisting the moment as strut, six specimens are designed and tested. Parameters in the test are column width, beam height and horizontal tie within beam depth. From the test, using either wide column width or ties, strength and stiffness of joint were developed. The lower beam height the specimens showed the lower moment.