• Journal of Forest and Environmental Science
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• v.39 no.2
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• pp.96-104
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• 2023

The successful restoration program requires a comprehensive understanding of variables influencing seedling efficiency. Below-ground is hypothesized to have a major impact on seedling performance of species when planted in agriculture, and degraded areas with different types of mulching. This study investigated on Sg. Terla Forest Reserve in Cameron Highlands Pahang, Malaysia. In this study randomized complete block design (RCBD) was used. The excavation method was applied to study the root system development, above, and below ground biomass distributions under different types of mulching: coconut mulching (CM), oil palm mulching (OM), plastic mulching (PM) and control (CK). The root diameter, main root length, lateral root length, root coiling, and root direction toward to sun were recorded. The results in this study indicate that mulching had significant effect on root diameter, main root length, and root distributions among treatments while for lateral root length, root: shoot ratio, dry biomass distributions, and above and below ground biomass did not showed significant effect among treatments. The highest values for root diameter, lateral root length, main root length, root distributions, dry biomass distributions and above and below ground biomass were showed in CM treatments. However 75% of root coiling was observed in seedlings between treatments.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.303-303
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• 2022

The purpose of this study was to evaluate agronomic characteristics and identify the useful traits to utilize the wheat genetic resources for breeding programs by understanding the phenotypic variation among germplasm through multivariate analysis. In this study, a total of 394 wheat accessions were characterized for 15 agronomic traits using the National Agrobiodiversity Center (NAC) descriptor list, of which 31 accessions from 6 species and 363 unidentified accession (Triticum spp.) available at the NAC, Rural Development Administration (RDA), Korea. Growth characteristics such as leaf width, culm length, spike length, spikelet length, solid stemmed, days to heading, days to maturity, grain-filing period, and also seed characteristics such as width, height, area, perimeter, circle, solidity, and germination percent were studied. Among the 15 agronomic characteristics, the germination percent showed the smallest variation between resources (CV = 0.4%), and the spikelet length (CV = 66.5%) showed the highest variation. A strong positive correlation was found between seed traits such as seed height and seed area (r = 0.90), seed height and seed perimeter (r = 0.87) and seed length and width (r = 0.80). Principal component analysis (PCA) was conducted and the first five principal components comprised 76.7% of the total variance. Among the first five PCs, PCI accounted for 28.5% and PC2 for 20.0%. Wheat resources (394) were classified into four clusters based on cluster analysis, consisting of 215 resources(I), 117 resources(II), 48 resources(III), and 14 resources(IV). Among the clusters, the resources belonging to Cluster III showed the lowest seed width, height, area, and perimeter characteristics compared to other clusters. The wheat resources belonging to cluster IV had small seed width and low germination percent, but took longer to form heads and mature than resources in other clusters. These results will serve as the basis for further genetic diversity studies, and important agronomic characteristics will be used for improving wheat, including developing high-yielding and resistant varieties to biotic and abiotic stresses via breeding programs.

• Journal of fish pathology
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• v.21 no.3
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• pp.181-188
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• 2008

Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used to detect and identify four fish viruses, fish iridovirus, viral hemorrhagic septicaemia virus (VHSV), viral nervous necrosis virus (VNNV), hirame rhabdovirus (HRV). Four viruses were detected by PCR with each specific primers. Identification of iridovirus was achieved by digesting the PCR amplified fragment with a restriction enzyme ApaⅠ. It was possible to distinguish positive from false positive PCR amplicons of VHSV by RFLP of PstⅠ or HindⅢ restriction enzymes. VNNV was identified using RFLP of BamHⅠrestriction enzyme and HRV was identified by XbaⅠ restriction enzyme. This approach can be used for more rapid, simple and specific diagnosis of fish viral diseases.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.110-111
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• 2019

In ACI 318-19 published recently, the conditions and development length equation to use the headed deformed bars were changed considerably. Although the use of the larger-diameter(No.14 and 18) headed deformed bars isn't yet permitted, the use of the high strength(80,000psi) headed deformed bars is permitted and the effect of bar-diameter($d_b$) on the development length is increased considerably. Therefore, structures using larger-diameter headed deformed bars will be expected to be affected by this code change. We will study the effect of the code change on the development design and find out the design optimization method to minimize the effect of the changed conditions and development length equation.

• Journal of the Korea Institute of Building Construction
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• v.9 no.6
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• pp.141-149
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• 2009

The objective of this study was to propose a development length equation for bottom and top GFRP bars. Including the bottom and top GRPP bars, a total of 104 modified pullout tests were completed. The test variables were embedment length (15, 30, 45db), net cover thickness (0.5~2.0db), different GFRP bar types, and bar diameters (10, 13, 16mm). The average bond stresses were determined based on the modified pullout test results. Two variable linear regression analyses were performed on the results of the average bond stresses. Utilizing the 5% fractile concept, a conservative development length design equation was derived. The design equation of the development length for bottom and top GFRP bars was proposed and the design equation derived in this study was compared to the ACI 440.1R-06 committee equation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5A
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• pp.485-493
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• 2010

GFRP rebar with ribs resemble those of deformed steel rebar was developed in 2005. It was reported that ribs of the GFRP rebar were sheared off due to the lower shear strength of polymer. In this study, the basic development length of the GFRP rebar was investigated through pull-out tests, models specified in ACI440.1R-03 and -06, and empirical model derived by Cosenza et al. (2002). As a results of pull-out tests, the critical embeddment length, which is defined as the length when failure mode is changed from pull-out to bar fracture, was 20 times of bar diameter for GFRP rebar and was 15 times for steel rebar. It is believed that the basic development of the GFRP rebar is 21 times of bar diameter, which is determined from the application of average bond strength into the model equation specified in ACI440.1R-03. Compared to the model equation in ACI440.1R-06, that in ACI440.1R-03 is recommendable for design purpose. The Cosenza et al.'s model underestimates the basic development length of the GFRP rebar.

• Korean Journal of Ichthyology
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• v.20 no.4
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• pp.285-290
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• 2008

Morphological characteristics of the cross-bred $F_1$ hybrid between female Paralichthys olivaceus and male Platichthys stellatus were studied. The hybrids showed common biological characteristics of both parents, but showed more morphological similarity to P. stellatus than P. olivaceusin the following biometries: higher ratios of body length to body height (56.3%), head length to snout length (20.6%), and head length to upper jaw length (34.2%). They also showed some significant biometric characteristics similar to P. stellatus, such as ratios of predorsal length (10.5%), prepectoral length (32.2%), preventral length (29.8%), and preanal length (28.0%) to body length. The hybrids had black spots on the dark brownish-green area near the eyes, and they lacked the small bony tubercles that area characteristic of Platichthys stellatus. The hybrids had unique bands: 6~20 bands on the dorsal fin and 5~10 bands on the anal fin that gradually lost their coloration towards the fin margins. The number of fin rays were 60~66 for dorsal fin, 40~51 for anal fin, 18~21 for caudal fin, and 11~12 for pectoral fin. The gills of the hybrids contained 13~18 gill rakers and 73~98 gill filaments. The vertebrae of the hybrids numbered 34~37, with 2~3 vertebrae fused from the start of the caudal vertebrae.

• Journal of the Korean Society for Railway
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• v.4 no.1
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• pp.9-15
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• 2001

The railways in Russia is a core of the industrial, trade and technological development. They changed the country for the best affecting all sides of its life. The total length of the railways in Russia is 87,500 km (7％ of the World railway network). They account for about a 25％ of the World freight and 15% of the passenger traffic. In terms of length of electrified railways Russia is a World leader and in terms of total length of tracks it is second after the USA. Annual freight turnover is the third after the USA and China. (omitted)

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.3
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• pp.480-491
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• 2010

This study investigates the body satisfaction and fitness apparel depending on age and silhouette. The subjects were 254 females 20~50 years of age living in Chungju South Korea. There are various body types in women over the age of 35, the lower part of the body-development type, regular type, the upper part of the body-development type, and the rectangular body type. In addition, there is a lower satisfaction level in circumferences related with apparel fit, especially in the sleeve length, armhole, and crotch length. Therefore, a size system is needed that considers various body types in ready-to-wear clothing for middle-aged women. Design, color, and pattern are most important in clothing purchases by unmarried women, but the ease of laundry management and price discounts are the most significant for clothing purchases by married women. The upper part of the body-development type is unsatisfactory in the size-fit of sleeve length and shoulder width, but the lower part of the body-development type is unsatisfactory in the circumference of the waist, hip, abdominal, girth of skirt, and crotch length. The rectangular body type and the lower part of the body-development type are unsatisfactory in movement comfort, especially in hip girth and crotch length. The upper part of the body-development type is unsatisfactory in the movement comfort of the chest and elbow girth.

• International Journal of Automotive Technology
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• v.2 no.3
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• pp.103-107
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• 2001

Many researches on pressure-swirl injectors due to the variety of application have been conducted on the effects of nozzle design, operating conditions, properties of liquid and ambient conditions on the flow and spray characteristics. The breakup length of conical emulsified fuel sheet resulting from pressure-swirl atomizer using in the oil burner was investigated with the digital image processing method with neat light oil and emulsion with water content of lotto% and the surfactant content of 1-3%. The injection pressure ranged from 0.1 to 1.2 MPa was selected. The various regimes for the stage of spray development within the experimental conditions selected in this study is newly suggested in terms of Ohnesorge number and injection pressure. The breakup length for both criteria show the same tendency even though the random nature of perforation and disintegration process of liquid sheet. The stage of spray development is widely different with the physical properties of liquid atomized, mainly viscosity of liquid. The breakup length decreases smoothly with increase in the injection pressure for the lower viscous liquid.