• 한국작물학회지
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• 제44권1호
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• pp.11-19
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• 1999

This experiment was conducted with nine wheat geno-types to choose the wheat which has excellent early vigour. 'Vigour 18' and 'ZL 59A' are excellent in the long coleoptile genotype, while 'Amery' and 'Janz' are excellent in the short coleoptile genotype. Responding to the growth stage and nitrogen level, Vigour 18 is predominant in the long coleoptile genogype, while Janz in the short coleoptile genotype. Responding to sowing density and nitrogen level, the higher the sowing density was, the shorter the leaf area of Vigour 18 and Janz. Also the leaf area turned out to larger in the plot fertilized with high nitrogen than in the plot fertilized with low nitrogen. This is true of leaf weight and root weight. Concerning specific leaf area (SLA) and leaf area ratio (LAR), the higher the sowing density was, the SLA tended to grow larger, while the SLA grew larger in the plot fertilized with low nitrogen, as were found in Vigour 18 and Janz. The roots of long coleoptile genotype, Vigour 18, turned out to grow longest on the plot sown with 3 seeds. While the roots of short coleoptile genotype, Janz, grew longest on the plot sown with 2 seeds. The relative growth rate (RGR) was the same at low N rates and high N rates. The RGR was 0.071 and 0.072 g $g^{-1}d^{-1}$ at low N rates and high N rates. The partitioning of RGR into net assimilation rate (NAR) and LAR showed that the average LAR at low N rates was similar to the LAR at high N rates. Variation within each cultivar in the LAR and NAR was small relative to the difference between them at low N rates and high N rates. Above ground mass was 8.2 mg greater at high N rates than low N rates, whereas leaf area was 0.05 $\textrm{m}^2$$kg^{-l}$ greater at high N rates than low N rates. The NAR was similar at low N rates and high N rates, whereas LAR was greater at high N rates (0.05 $\textrm{m}^2$$kg^{-l}$); variation in SLA was responsible for the variation in NAR and LAR both at low N rates and high N rates. NAR was more closely associated with the reciprocal of SLA.

• 대한기계학회논문집A
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• 제25권12호
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• pp.2091-2099
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• 2001

Fatigue crack growth behavior of inclined cracked Al 6061-T6 thick aluminum plate(6mm) repaired with the bonded composite patch was studied. A 0°inclined crack bonded reinforced composite patch and 15°, 30°, 45°, 60°inclined crack plates were tested. The effect of patch and inclined angle were studied and compared to each other. Also we investigated to the crack propagation direction and debonding behavior during the fatigue crack growth test. In this paper. a study was con(ducted to get an fatigue life, fatigue crack growth ratio and crack growth direction. Finally, the effectiveness of composite patch on inclined cracked plate was investigated. The results demonstrated thats there was a definite variation in fatigue life and fatigue crack growth behavior depending on the inclined crack angle.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.220-225
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• 2004

The mesh-insensitive structural stress procedure by Dong is modified to apply to the welded joints with local thickness variation and inignorable shear/normal stresses along local discontinuity surface. In order to make use of the structural stress based K solution for fatigue correlation of welded joints, a proper crack growth model needs to be developed. There exist some significant discrepancies in inferring the slope or crack growth exponent in the conventional Paris law regime. Two-stage crack growth model was not considered since its applications are focused upon the fatigue behavior in welded joints in which the load ratio effects are considered negligible. In this paper, a two-stage crack growth law considering high mean loading is proposed and proven to be effective in unifying the so-called anomalous short crack growth data.

• 한국생산제조학회지
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• 제19권5호
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• pp.637-644
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• 2010

This paper presents a reliability-based shape optimization (RBSO) using the growth-strain method. An actual design involves uncertain conditions such as material property, operational load, Poisson's ratio and dimensional variation. The purpose of the RBSO is to consider the variations of probabilistic constraint and performances caused by uncertainties. In this study, the growth-strain method was applied to shape optimization of reliability analysis. Even though many papers for reliability-based shape optimization in mathematical programming method and ESO (Evolutionary Structural Optimization) were published, the paper for the reliability-based shape optimization using the growth-strain method has not been applied yet. Growth-strain method is applied to performance measure approach (PMA), which has probabilistic constraints that are formulated in terms of the reliability index, is adopted to evaluate the probabilistic constraints in the change of average mises stress. Numerical examples are presented to compare the DO with the RBSO. The results of design example show that the RBSO model is more reliable than deterministic optimization. It was verified that the reliability-based shape optimization using growth-strain method are very effective for general structure. The purpose of this study is to improve structure's safety considering probabilistic variable.

• Ocean and Polar Research
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• 제39권4호
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• pp.245-255
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• 2017

There are a number of pieces of evidences that suggest a link between marine diatoms and microorganisms, but knowledge about related microbial communities is greatly lacking. The present study investigated the microbial community structures related to the growth of the marine diatom Cyclotella meneghiniana. We collected free-living bacteria (FLB) and particle-associated bacteria (PAB) at each growth stage (e.g., lag, exponential, stationary and death) of the diatom, and analyzed their bacterial 16S rDNA using pyrosequencing. Metagenomics analysis showed that community structures of FLB and PAB differed considerably with the progress of growth stages. FLB showed higher diversity than PAB, but variation in the different growth stages of C. meneghiniana was more evident in PAB. The proportion of the genus Hoeflea, belonging to the order Rhizobiales, was dominant in both FLB and PAB, and it gradually increased with the growth of C. meneghiniana. However, Enhydrobacter clade tended to considerably decrease in PAB. In addition, Marinobacter decreased steadily in FLB, but first increased and then decreased in PAB. These results suggest that Hoeflea, Enhydrobacter, and Marinobacter may be closely related to the growth of diatom C. meneghiniana.

• 한국재료학회지
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• 제27권11호
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• pp.609-616
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• 2017

We investigated a Leidenfrost effect in the growth of ZnO nanostructures on silicon substrates by ultrasonic-assisted spray pyrolysis deposition(SPD). Structural and optical properties of the ZnO nanostructures grown by varying the growth parameters, such as substrate temperature, source concentration, and suction rate of the mist in the chambers, were investigated using field-emission scanning electron microscopy, X-ray diffraction, and photoluminescence spectrum analysis. Structural investigations of the ZnO nanostructures showed abnormal evolution of the morphologies with variation of the substrate temperatures. The shape of the ZnO nanostructures transformed from nanoplate, nanorod, nanopencil, and nanoprism shapes with increasing of the substrate temperature from 250 to $450^{\circ}C$; these shapes were significantly different from those seen for the conventional growth mechanisms in SPD. The observed growth behavior showed that a Leidenfrost effect dominantly affected the growth mechanism of the ZnO nanostructures.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.398-404
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• 2003

Most previous researches for the hybrid composite materials such as FRMLs(Al/AFRP, Al/GFRP) have evaluated the fatigue delamination behavior using the traditional fracture mechanism. However, most previous researches have not generally been firmed yet. Because delamination growth behavior in hybrid composite should be consider delamination growth rate, $dA_D$/da using the delamination shape factors, fs instead of traditional fracture mechanic parameters. The major purpose of this study was to evaluate the relationship between delamination shape factor, fs and delamination growth rate, $dA_D$ . And a propose parameter on the delamination aspect ratio, b/a. The details of the study are as follow : 1) Relationship between crack length, a and delamination width,b. 2) Relationship between delamination aspect ration, b/a and delamination area rate,($(A_D)_{N}(A_D)_{ALL}$. 3) Variation of delamination growth rate, $dA_D/da$ was attendant on delamination shape factors, $fs_1$, $fs_2$, $fs_3$. The test results indicated the delamination growth rate depends on delamination shape factors.

• Asian-Australasian Journal of Animal Sciences
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• 제3권3호
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• pp.155-159
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• 1990

The growth of lean from nine wholesale cuts in relation to the total lean weight in carcass side were evaluated with three allometric equations for 18 Najdi male camels slaughtered at 8, 16 and 26 months of age. The allometric growth coefficients indicated that as the camels grew, weights of lean form brisket and flank cuts increased relatively more rapidly than the total lean in carcass side (${\beta}$ >1.1) and that weights of lean from wholesale shoulder and rump cuts increased relatively less rapidly (${\beta}$ <.9) than the total lean weight from carcass side. The growth coefficients for the lean in the thoracic limb and pelvic limb showed a dorsoventral rise in the growth impetus, with coefficients for the thoracic limb correspondingly higher than those of pelvic limb. The growth coefficients for the lean from shoulder, rib, flank and leg cuts increased (p<.01) with increased weight of total lean in carcass side, whereas it decreased with increased total lean weight in carcass side for the lean in neck, brisket, plate, loin and rump cuts. At a constant weight of total lean in carcass side, older camels had larger coefficients for lean in neck, brisket, rump, flank and leg cuts, but had smaller coefficients for lean in shoulder, rib, plate and loin cuts.

• 자원환경지질
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• 제24권3호
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• pp.219-226
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• 1991

High quality quartz crystals are grown in 0.5N NaOH + LiOH solution on the seed crystal at $370-395^{\circ}C$ and $1200-1300kg/cm^2$ condition. Growth rates are determined by the crystal thickness grown on the seed crystals with Z(0001) and X($11\bar{2}0$) direction. Relatively high growth rate of Z(0001) direction gradually changes as the temperaure difference (${\Delta}$ Ti) between growth and dissolution zones from 25 to $10^{\circ}C$. The X axis direction is affeced by ${\Delta}$ Ti, and +X($11\bar{2}0$) direction shows a high growth rate than -X($\bar{1}\bar{1}20$) direction. According to the variation with kinds of solutions used, the crystal growth that in NaOH solution is found to be slower than that in $Na_2CO_3$ solution. However, for the case in the NaOH solution mixed with LiOH, it shows a favorable growth rate in terms of grown crystal quality.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 추계국제학술대회
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• pp.59-59
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• 2020

Salix gracilistyla has a characteristic of fast growth especially in the river side or infertile soil, showing a lot of lateral branches and a strong root system among the Salix. spp. On the basis of results observed, we provide several growth characteristics of S. gracilistyla among some selected provenances. In two-year results, root collar diameter ranged from 33.5 mm to 56.7 mm. Taeback showed the lowest value, and Jeongseon and Hoengseong were higher than the other areas in the traits above. Height growth was the lowest in Samcheok and the highest in Wonju. To examine growth and development of lateral branches is important because S. gracilistyla has a lot of lateral branches which account for high biomass production. Length of lateral branch showed high variation, in which the highest number was observed in Yeongwol and the lowest in Samcheok. Many lateral branches were shown in Wonju. Preliminary study on biomass resources evaluation, we analyzed correlation between volume and length, and volume and root diameter. High correlation was observed between root diameter and plant volume. And we compared the observed volume with the caculated volume by regression formula. To evaluate Salix species as biomass resources, it is needed to survey growth characteristics continuously and adopt selection of individuals or families of high biomass and caloric values by reliable data. In addition, Salix spp. can be also applicable to selection breeding regime because of feasible propagation and fast growth.