• Journal of Radiation Protection and Research
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• v.30 no.1
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• pp.1-7
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• 2005

Radiation absorption parameters of carbon fiber panel were measured in comparison to acrylic panel. $30{\times}30cm$ sized 2mm thick carbon fiber panel and identical sized 6mm thick acrylic panel were placed in tray holder position and 0cm, 5cm, 10cm from surface of phantom. Radiation field size was $10{\times}10cm$. 50MU of 4MV photon was irradiated to the phantom with dose rate of 300MU/min. Source-to-phantom distance was 120cm. Radiation dose was measured with 0.6cc Farmer-type ionization chamber with 1cm build-up. Measurement was repeated thrice and normalization was done to the dose of the open field. Radiation transmission rate of carbon fiber panel is approximately 1% lower than acrylic panel of equivalent thickness. However, considering the strength of the material, transmission rate is higher for carbon fiber panel. Although carbon fiber panel increases the radiation dose when attached to the surface for about 2%, it normalizes the radiation dose to 97-99% of irradiated dose which could have been lowered to as much as 5-7.5% with acrylic panel. As carbon fiber panel is stronger than acrylic panel, radiation fixation device could be made thinner and thus lighter and furthermore, with increased radiation transmission. This in turn makes carbon fiber more ideal material for radiation fixation device over conventionally used acrylic.

• Journal of Animal Science and Technology
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• v.48 no.1
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• pp.77-90
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• 2006

The purpose of this study was to isolate cellulolytic and hemicellulolytic anaerobic bacteria inhabiting from gut of ruminants and investigate their hydrolytic enzyme activities. Extracellular CMCase activities of H-strains isolated from the rumen of a Holstein dairy cow were higher than those of D- and DC- strains from the rumen and large intestine of Korean spotted deer. Most isolated bacteria utilized more efficiently Dehority's artificial medium containing starch, glucose and cellobiose (DAS) than those in Dehority's artificial medium containing cellulose only (DAC). The results of biochemical reactions and sugar fermentation indicated that the isolated bacteria belong to one of bacterial strains of Peptostreptococcus spp., Bifidobacterium spp., Prevotela ruminicola/buccae, Clostridium beijer/butyricum and Streptococcus intermedis which are not highly cellulolytic. Activities of Avicelase, xylanase, β-D-glucosidase, α-L-arabinofuranosidase and β-xylosidase of the isolated anaerobic bacteria in DAS were higher than those in DAC. In conclusion, the results indicated the higher enzyme activities of the isolated strains cultured in DAS medium were mainly caused by their specific carbohydrate utilization for enzyme production and growth rate. The highly cellulolytic bacteria were not isolated in the present experiment. Thus further research is required to investigate characteristics of gut bacteria from Korean spotted deer.

• Journal of the Korean Geosynthetics Society
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• v.11 no.2
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• pp.39-47
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• 2012

This paper describes large-scale pullout test results of geosynthetic strip, which can be applied in reinforced earth wall with block-type wall facing. The pullout tests are conducted to evaluate the strain distribution, the induced pullout force and the pullout strength. The maximum pullout force is appeared regardless of reinforcement width and normal stress when end displacement is less than 15 mm. The pullout behavior based on horizontal spacing of reinforcement was similar in relationship between pullout force and end displacement. The strain distribution and pullout force distribution of the geosynthetic strip are concentrated in the front part of reinforcement, and it appeared clearly in higher normal stress condition This means that the pullout behavior of geosynthetic strip is affected by the bond between soil and friction resistance reinforcement according normal stress. Therefore, the pullout resistance design is reasonable when pullout behavior of geosynthetic strip should be evaluated by effective length considering tensile characteristic.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1322-1326
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• 1997

Characteristics of viscosity and spray dried particles for several polysaccharides were studied to investigate the possibilities as wall materials for microencapsulation. Viscosities of 10% maltodextrin, 10% gum arabic, 10% dextran, 1% gum locust bean, and 1% gum karaya were 2.2 mPa.s, 9.2 mPa.s, 13.0 mPa.s, 4660.0 mPa.s, and 77.0 mPa.s, respectively. In scanning electron micrographs for spray dried polysaccharides, gum arabic had spherical shapes at 20% and 30% emulsion concentration, while trailed shapes at 40%. Maltodextrin had uniform spherical shapes at 30%, while aggregated form with various kinds of capsule sizes at 40%. Dextran had spherical shapes at 20%, while trailed fibrous shapes at over 30%. Mixed polysaccharides with gum arabic:maltodextrin (1:3, w/w) had uniform spherical shapes at 20%, 30%, and 40% with increasing diameter with increasing concentration.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.17-20
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• 2006

Recently, in order to reduce the spalling of high strength concrete under fire, the addition of organic fibres to high strength concrete has been investigated. In this study, the effect of fiber length and specimen size on the spalling and temperature distribution in high strength concrete specimen was experimentally investigated. Three HSC specimens measuring $305{\times}305mm$, $500{\times}500mm$ and $700{\times}700mm$ with the fiber were prepared. The fiber length was 6mm and 10mm. As a result, it appears that when the remaining ratios(by weight) of fibre at $300^{\circ}C$ and $350^{\circ}C$ are less than 80% and 50%, respectively, the spalling of high strength concrete is prevented.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.535-536
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• 2009

This study was carry out to evaluate the durability of Ductile Fiber Reinforced Cementitious Composites(DFRCC) according to W/B ratio(30, 40, 50%). The results is showing that DFRCC outstandingly improved to compare to plain concrete for the resistance of chloride ion penetration and rapid freezing and thawing

• Tuberculosis and Respiratory Diseases
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• v.41 no.3
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• pp.248-261
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• 1994

Background: Lectins are proteins or glycoproteins of non-immune origin that recognize a specific sequence of sugar residues. The availability of a large number of lectins has provided the capacity to identify selectively glycoconjugates possessing distinctive chemical structure in diverse sites of highly specialized biological activity. The purpose of the present study was to investigate the lectin binding patterns of various components in human pulmonary tubercles. Method: Biopsy specimens of tuberculous lung were obtained from male adult patients who underwent a surgical resection for severe pulmonary tuberculosis. The specimens were processed and stained with 13 kinds of biotinylated lectins according to some modification of Hsu and Raine's methods. Results: 1) In the caseous necrotic lesions, BS $I-B_4$ showed negative reaction and BS I were also negative except some irregularly-shaped cells located in the marginal zone. All other lectins, however, showed a positive reaction with various binding patterns. 2) The epithelioid cells were broadly divided into three groups according to the reaction patterns in the cytoplasms and cell membranes. 3) WGA, ECL, PHA-L, PHA-E and LCA showed strong staining in the lymphocytes. 4) SBA showed a different binding patterns between the endothelial layers located in the region beyond the fibrous layers and those located within the fibrous layers. 5) PNA showed a positive reaction in the outer 1/3 to 1/2 of the fibrous layer, but showed no staining in the inner 1/2 to 2/3 of the fibrous layers. Conclusion: The present lectin histochemical study provided a useful information to assess the characterization and distribution of various glycoconjugates in each constituent of human pulmonary tubercles. The results demonstrate structural differences in the glycoconjugate composition of various components of the tubercles and reveal changes in glycosylation in the components during soft tubercle formation. This study provides a new data useful for the studies on the pathogenesis and pathology of human pulmonary tubercles.

• Journal of the Korea Concrete Institute
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• v.28 no.5
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• pp.581-592
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• 2016

Tensile constitutive stress-strain model of steel fiber reinforced concrete (SFRC) in fib MC2010 was investigated. In order to model tensile behavior of SFRC, three point loading flexural tests were conducted on notched small beams according to BE-EN-14651. Design parameters for the constitutive model were determined from the flexural tests. Flexural test and finite element analysis were conducted on large SFRC beam without steel reinforcements and compared with each other. In addition, parametric study on the effect of compressive and tensile model, and characteristic length on flexural behavior of the SFRC beam was conducted also. In results, pre-peak load-displacement curves from the FE analysis was close to experimental curves but significant difference was shown in post-peak behavior. The reason of the difference is originated from the fact that the fiber distribution and orientation were not being properly considered in the MC2010 model. This study shows that modification and detail explanations on the orientation factor K in MC2010 might require to better reproduce the behaviour of large scale SFRC beams.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.3
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• pp.25-34
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• 2018

This paper presents a heating source of carbon nanofibers for the efficiency and the drying performance of laundry dryer, and focuses on the applicability-evaluation of its source. To design the proposed heating module, experiments were conducted in terms of surface temperature and surface temperature distribution characteristics of carbon nanofiber lamps. The surface temperature of the lamps increased linearly with increment of a current to flow a lamp and revealing the increasing pattern as the length of the ramps is shorter. The proposed heating source was evaluated based on drying efficiency, moisture evaporation rate at laundry, and internal temperature of a drum during drying process. The drying efficiency satisfied a 45% which is specified in KS C 9319. The moisture evaporation rate and the internal temperature of the drum were respectively 98.88% and $61.1^{\circ}C$, which are similar to that of S's company dryer. From the evaluation and actual drying test results, the proposed carbon nanofiber lamp heating module is considered to be applicable as a heat source for laundry dryer in terms of drying efficiency and drying performance. it is possible to obtain a heat source at a high temperature, an excellent calorific value, an improvement in drying performance, and an effect of sterilizing laundry due to the emission of far-infrared rays. In addition to the applicability, the difference of the drying efficiency between the dryers was analyzed in detail based on the power consumption of the heat sources.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.3
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• pp.187-190
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• 2006

In order to produce hemp with low cannabinoids and appropriate fiber yield, seeds of the IH3 (non drug type germplasm) and local variety (drug type cultivar) were mixed to 1:1, 2:1, 3:1 on base of seed weight ratio and cultivated for seed production. In the seed yield trial, the weight of 1000 grains were around 21 g, which was increased in proportion to the ratio of IH3 seeds but seed yield were 100 kg/10a, which were not significantly different by the seeds-mixing ratio. In fiber yield trials with seeds from seed yield trial, fiber yield ranged $193{\sim}198kg/10a$ which was not significantly different by the seeds mixing ratio but the content of THC(${\Delta}$-9-tetrahydrocannabinol) was lowered in proportion to the ratio of IH3 seeds. Variation of THC and CBD (Cannabidiol) level in the 150 plant cultivated with various seed mixing ratio reflected that the percentage of drug and intermediate type were decreased but non drug type were increased in proportion to the ratio of IH3 seeds.