• 한국작물학회지
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• 제43권1호
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• pp.32-37
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• 1998

The objective of this study was to analyze lodging-related traits using different cultivars from Korea, Japan, and the U.S. in direct seeded rice on dry paddy field. Stem diameter and culm wall thickness were highest in 'Caloro' followed by 'Nongan', 'M202', and 'Calrose'. All the U.S. cultivars were higher than the others in stem diameter and culm wall thickness. These two traits were important with regard to lodging. The highest breaking strength (1442g) was observed in Caloro. 'Gancheoek', 'Dongjin', and transplanted 'Hatsuboshi' showed more than 1000g in breaking strength. Lodging index was lowest in Hatsuboshi followed by Nongan and Gancheok. Even though breaking strength of the U.S. cultivars was higher than others, their lodging index values were high. There were no statistically significant differences in starch content. However, Calrose, Caloro, Dongjin, and Koshihikari were relatively higher than others in starch content. Positive correlations were found between culm base weight, lignin and breaking strength. High contents of lignin and cellulose were observed in Nongan, transplanted Hatsuboshi, Calrose, and Caloro. Traits such as stem diameter, culm wall thickness, bending moment, culm length, breaking strength, cellulose, lignin, and culm base weight were closely related to a lodging index. According to path coefficient analysis, most important traits were culm length, stem diameter, thickness of clum wall, and top plant weight.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.429-429
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• 2008

The structural stability and the elastic modulus of hexagonal ZnO nanowires and nanotubes are investigated using atomistic simulations based on the shell model. The ZnO nanowire with (10-10) facets is energetically more stable than that with (11-20). Our calculations indicate that the structural change of ZnO nanowires with (10-10) facets is sensitive to the diameter. With decreasing the diameter of ZnO nanowires, the unit-cell length is increased while the bond-length is reduced due to the change of surface atoms. Unlike the conventional layered nanotubes, the energetic stability of single crystalline ZnO nanotubes is related to the wall thickness. The potential energy of ZnO nanotubes with fixed outer and inner diameters decreases with increasing wall thickness while the nanotubes with same wall thickness are independent of the outer and inner diameters. The transformation of single crystalline ZnO nanotubes with double layer from wurtzite phase to graphitic suggests the possibility of wall-typed ZnO nanotubes. The size-dependent Young's modulus for ZnO nanowires and nanotubes is also calculated. The diameter and the wall thickness play a significant role in the Young's modulus of single crystalline ZnO nanowires and nanotubes, respectively.

• Journal of the Korean Wood Science and Technology
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• 제25권2호
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• pp.117-126
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• 1997

In fast grown softwood, there are very large changes in material properties going outward from the pith to bark such as anatomical, physical and mechanical characteristics. Some of variations in anatomical properties with annual ring were then examined from Pinus koraiensis, Larix leptolepis, and Chamaecyparis obtusa, which are major softwoods of plantation in Korea. The large variations of annual ring width during young age of tree tended to stabilize after 25year through the transitional period in 17~23year. The ring density was 1.5~2.4 in 1~10year period, and 3.5~6.3 in 30~35year period, in which juvenile and mature wood were certainly assumed to be formed, respectively. Variations of tracheid length showed functional relationships with annual rings as logarithm. Demarcation between juvenile wood and mature wood could be 16~19year, which was determined from increase rate of tracheid length of 0.2%. Cell wall thickness increased with increase of annual ring even though large variations were observed as well. Variations of cell wall thickness within species were pronounced in latewood than earlywood. The increase of cell wall thickness from juvenile wood to mature wood was predominant in Larix leptolepis as 2.0times, and least in Chamaecyparis obtusa as 1.1 times. Cell diameters showed trends of increase during young age of 1~15year, and consistent afterward. The variations of cell diameter between radial and tangential direction were greater in latewood, and most pronounced in Chamaecyparis obtusa.

• 한국가구학회지
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• 제17권4호
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• pp.49-57
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• 2006

Larix kaemferi is now a major economic kind of trees and is produced in large quantity every year. Thus, the study of Larix kaemferiis conducted to acquire the basic date of measures for the reasonable use, clarifying the relation with the compression strength parallel to grain according to anatomical properties by heartwood and sapwood, and earlywood and latewood. As the length of an earlywood tracheid and the radial wall thickness of earlywood and latewood tracheids increased, the compression strength rose, and as the height of uniseriate ray in cell number increased, the compression strength parallel to grain fell. The major anatomical factors effecting on the compression strength parallel to grain of heart wood were the radial wall thickness of a latewood tracheid and the length of a latewood tracheid, while in sapwood, the length of an earlywood tracheid and the radial wall thickness of earlywood and latewood tracheids were the major factor on it.

• Archives of Pharmacal Research
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• 제26권8호
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• pp.638-643
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• 2003

Raw milk samples, and cow and chicken intestines were tested to isolate vancomycin-resistant, gram-positive bacteria. From these samples, we isolated seven vancomycin-resistant Streptococcus equinus, two vancomycin-resistant viridans Streptococcus and two vancomycin-resistant Enterococcus faecium. The MICs of several antibiotics, including vancomycin, against these strains were tested. Seven isolates of S. equinus showed high level resistance to vancomycin and teicoplanin (＞100 $\mu$ g/mL). The cell wall thickness of these strains was compared with that of the sensitive strain by TEM and no differences were obserbed between these strains. We compared the strains of vancomycin-resistant Streptococcus equinus using PCR with Microbial Uniprimer Kit. We concluded that it is necessary to combine other methods in order to cluster and identify all isolates of S. equinus.

• 한국환경농학회지
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• 제31권1호
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• pp.30-36
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• 2012

BACKGROUND: The resistance of rice bakanae disease pathogens against the fungicide prochloraz has been reported. Understanding the resistance mechanisms is an important for better control of the pathogens. In the present study, we investigated the resistance mechanisms of Fusarium fujikuroi CF337 (CF337) against prochloraz. METHODS AND RESULTS: Morphological changes in the cell wall of CF337 grown in potato dextrose broth (PDB) with or without prochloraz was investigated by transmission electron microscopy. Growth inhibition of CF337 was examined in PDB containing prochloraz or an ABC transporter inhibitor or both of them. Cell wall thickness of CF337 grown in PDB with prochloraz was significantly increased from $80.73{\pm}1.99nm$ to $193.11{\pm}7.07nm$. Significant inhibition in the growth of CF337 was observed in the presence of both prochloraz and the inhibitor, but no growth inhibition was observed in the presence of the inhibitor or prochloraz. Sequence analysis of ATP-binding cassette transporter (ABC) gene of CF337 showed 70 to 80% similarities to the genes of the pathogens resistant to other fungicides. CONCLUSION: Efflux transporter system and changes in cell wall thickness were suggested as resistance mechanisms of CF337 against prochloraz.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.474-481
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• 2001

This paper addresses a numerical method for predicting transient temperature distributions in the wall of a curved pipe subjected to internally thermal stratification flow. A simple and convenient numerical method of treating the unsteady conjugate heat transfer in the non-orthogonal coordinate systems is presented. The proposed method is implemented in a finite volume thermal-hydraulic computer code based on a cell-centered, non-staggered grid arrangement, the SIMPLEC algorithm, a higher-order bounded convection scheme, and the modified version of momentum interpolation method. Calculations are performed for the transient evolution of thermal stratification in two curved pipes, where the one has thick wall and the other has so thin wall that its presence can be negligible in the heat transfer analysis. The predicted results show that the thermally stratified flow and transient conjugate heat transfer in a curved pipe with a finite wall thickness can be satisfactorily analyzed by the present numerical method, and that the neglect of wall thickness in the prediction of pipe wall temperature distributions can provide unacceptably distorted results.

• 원예과학기술지
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• 제35권3호
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• pp.300-313
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• 2017

'Unicon' cherry tomato (Solanum lycopersicum) is one of the most highly perishable horticultural crops due to its high water content and respiration rate. This study was carried out to assess the effect of continuous application of $CO_2$ (control [air], 3%, and 5%) on the quality and shelf life of cherry tomato fruits stored at $10^{\circ}C$ and $85{\pm}5%$ relative humidity (RH) at two maturity stages (pink and red). Continuous application of $CO_2$ did not affect the soluble solids content (SSC) or titratable acidity (TA) of the fruit at either maturity stage during storage. However, there was a significant difference among treatments in terms of flesh firmness, cell wall thickness, pectin content, vitamin C content, skin color, lycopene content, weight loss, ethylene production rate, respiration rate, and acetaldehyde and ethanol production. Fruits treated with 5% $CO_2$ maintained their high quality with regards to vitamin C, skin color ($a^*$), lycopene content, weight loss, physiological parameters (ethylene production rate, respiration rate, and volatile compounds), flesh firmness, cell wall thickness, and pectin content at both maturity stages compared with 3% $CO_2$ treatment and the control. Continuous application of $CO_2$ (5%) reduced the ethylene production rate and the production of volatile compounds during storage. Therefore, cherry tomato 'Unicon' fruit can be stored for two weeks without losing fruit quality at both maturity stages under continuous application of 5% $CO_2$ as a postharvest treatment.

• 소성∙가공
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• 제17권8호
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• pp.657-661
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• 2008

Recently, products of electronic industry and related parts are required to have the thickness thinner and thinner to reduce the part weight. To go with this trend, LGP(light guide plate) of LCD-BLU(Liquid Crystal Display-Back Light Unit: It is one of kernel parts of LCD) for cell phone has the thickness of ${\sim}0.3mm$ and the battery case of cell phone has ${\sim}0.25mm$. Accordingly, high speed injection molding is required to mold products which have thinner parts. To achieve high speed injection and proper control of hydraulic unit, various design was applied to conventional injection unit. In the present paper, we concentrated on the molding stability of hydro-mechanical high speed injection machine to make an LGP of 0.3mm thickness.

• Journal of Plant Biology
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• 제29권4호
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• pp.295-315
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• 1986

Structure and differentiation mechanism of the seed coat of Panax ginseng are studied with light and electron microscopes to clarify the developmental processes of seed coat and the structural changes during the differentiation of the seed. The seed coat of ginseng is differentiated from the inner cell layers of ovary wall, which can be compared with the seed coat differentiated from integument(s) in other plants. The single integument is differentiated into endothelium, which is degenerated to one layer of 4${\mu}{\textrm}{m}$ in thickness, composed of remants of cell wall components in fully ripened seed. The ripened seed coat is composed of three layers; fringe layer, inner layer and palisade layer, and all of the them are crossed at right angles with one another. This may be the cause of protection of the kernel from other mechanical injuries. The thickness of fully ripened seed coat is about 300~600 ${\mu}{\textrm}{m}$, and arrangements of sclereids are irregular. However, the raphe region of seed coat is thin about 200 ${\mu}{\textrm}{m}$ in thickness and sclereids in that region are arranged regularly. This is the important cause for the cleavage of the seed coat during post-maturation process. The vascular bundles on the raphe are still remaining after sarcocarps are removed, and one of the branches of vascular bundles entered into the seed coat through the hilum and extended to chalazal region. During post-maturation process, the supply of water being necessary for growth of embryo may be accompolished by the vascular bundles entered into the seed coat through the opened hilum.