• Proceedings of the KSME Conference
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• 2001.06d
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• pp.807-812
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• 2001

This paper represents the wall thinning analysis results for secondary side piping of two types of domestic nuclear power plants based on the DB establishment and F AC analysis study for NPP secondary system piping. CHECWORKS code utilized in this study has been applied world widely to wall thinning analyses for secondary side piping and its reliability has also been proved. The predicted wear rates for several piping systems of a pressurized water reactor NPP are compared with those of a pressurized heavy water reactor NPP and with the measured wear rates. On the basis of comparison results of the predicted and measured wear rates, the analysis results can be effectively applied to the development of a standard thinned pipe management program targeted all domestic nuclear power plants.

• Textile Coloration and Finishing
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• v.10 no.6
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• pp.20-26
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• 1998

100％ viscose rayon fabric was treated with 1,2,3,4-butanetetracarboxylic acid (BTCA) by pad-dry-cure process in the presence of various catalysts. The dimensional stability, mechanical properties and hand values of fabric treated with BTCA were investigated. The ester-crosslinking reaction was influenced by the concentration of BTCA and type of catalyst. The fabric treated with BTCA was comparable or superior to that treated with conventional crosslinking agents such as dimethyloldihydroxyethyleneurea and 4,5-dihydroxy-1,3-dimethyl-2-imidazolidinone in respect of wrinkle recovery, shrinkproof property, retention of strength, and hand values. But in yellowing of fabric, the fabric treated with BTCA was inferior to that treated with conventional crosslinking agents. The fabric treated with BTCA/sodium formate was inferior to that treated with BTCA/sodium hypophosphite in respect of WRA, but had better strength retention and whiteness.

• Fibers and Polymers
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• v.5 no.3
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• pp.230-233
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• 2004

The optimum conditions for durable press treatment of cotton fabrics using glyoxal as a nonformaldehyde crosslinking agent were investigated. Crosslinking reaction was conducted in the presence of different catalysts such as aluminum sulfate, magnesium chloride, or magnesium chloride-citric acid mixture at various mole ratios of catalyst to glyoxal. Aluminum sulfate was proven the most effective one among those used. Glycol addition into a glyoxal padding bath increased the wrinkle recovery angle(WRA) and whiteness of treated fabrics. The optimum mole ratio of glycol to glyoxal was 1:1. Diethylene glycol addition produced better overall performance to the glyoxal-crosslinked fabric compared to ethylene glycol addition.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.1615-1617
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• 2009

The water resources project of 320 Ha second stage reclamation, in which including an University City, out of 800 Ha Ndata Farm, Malawa, had been under studied in this research. The challenge of C value of runoff coefficient was obtained as 0.8, by introducing the attenuation factors method, proposed by second author, an IDF dimensionless method customary used in Taiwan, proposed by the third author, is translated further to solve the project design rainfall; Rational Method, thus, obtains 11.5 CMS as the 5 year recurrence storage. The final job, completed by the third author's on-site performance, includs field alignments and discussions with the trustee, Malawa President H. E. Dr. Bingu Wa Mutharika, when a special concern of anti-theft. In order to provide sufficient supply up to an amount of 44,000 M3 during April to November, the sketch package includes 6 measurements: one water barrage, one sluice gate, one intake, one sediment reservoir, one water reservoir, and 3199 Km long gravity-driving hydraulic pipe.

• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.3
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• pp.323-335
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• 2020

In this study, a series of site measurement of particulate and gases pollutants at five tunnels were carried out along with case studies to review the suitability of the current road tunnel ventilation design standards. Previous studies by other researchers have shown that the ratios of the level of measurement to the standard were 27.9%, 1.6% and 3.4% for TSP, CO and NOx, respectively. Those measured in this site study shows even lower ratios; the ratios were 2.6%, 0.8% and 0.3%, for TSP, CO and NOx, respectively. The particle size analysis of TSP for the five tunnels shows that PM10 including tire wear and re-suspended road dust exceeded 20.4%. This implies that non-exhaust particulate matter must be taken into account, since the current design standards for the particulate matter (visibility) include only the engine emission. Based on the recent research results, for vehicle emission rate and slope-speed correction factors, revision of ventilation design standards for pollutants is required. WRA (PIARC) also emphasizes the necessity of the ventilation design standards for pollutants. In addition, enactment of a new road tunnel ventilation system operation standard or guideline is strongly recommended when considering the low operating rate of the ventilation system with jet-fans.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.1
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• pp.144-153
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• 2001

The effect of crosslinking on hand of the cellulase treated Tencel fabrics was investigated. Tencel fabrics were crosslinked with DMDHEU, mechanically prefibrillated, hydrolyzed by cellulase, and treated with softener. The treated fabrics were characterized by add-on, weight loss, DP rating, WRA, strength, SEM analysis and hand measurement. As DMDHEU concentration increased, weight loss of DMDHEU/cellulase treated fabrics decreased. However, cellulase treatment decreased DP properties and strength retention. Less fibrils were observed in the cellulase treated fabrics after DMDHEU treatment than the cellulase treated ones. It was confirmed that crosslinking with DMDHEU treatment was effective to control fibrillation. At 5% of DMDHEU concentration, DMDHEU/cellulase treated fabrics showed softer, smoother and bulkier hand compared with other treated fabrics. Among mechanical properties, bending and shearing properties were decreased progressively through DMDHEU, cellulase, and softener treatment. DMDHEU treatment contributed to impart resilience, cellulase treatment to bulkiness and softener treatment to smoothness. As the treatment of DMDHEU, cellulase, and softener progressed NUMREI, FUKURAMI, and THV increased with the exception of KOSHI.

• Wind and Structures
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• v.20 no.1
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• pp.59-74
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• 2015

A coupled model system for Wind Resource Assessment (WRA) was studied. Using a mesoscale meteorological model, the Weather Research and Forecasting (WRF) model, global-scale data were downscaled to the inner nested grid scale (typically a few kilometers), and then through the coupling Computational Fluid Dynamics (CFD) mode, FLUENT. High-resolution results (50 m in the horizontal direction; 10 m in the vertical direction below 150 m) of the wind speed distribution data and ultimately refined wind farm information, were obtained. The refined WRF/FLUENT system was then applied to assess the wind resource over complex terrain in the northern Poyang Lake region. The results showed that the approach is viable for the assessment of wind energy.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.505-508
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• 2004

This paper investigated the setting and compressive strength of concrete with the combination of mineral and chemical admixture. According to test results, plain concrete with high early strength development type AE water reducing agent(HEAEWRA) and $10\%$ of CKD respectively had earlier setting time than concrete with AE water reducing agent by $0.5\~1.5$ hours. Setting time of concrete with retarding type AE water reducing agent(RAEWRA) and FA $30\%$, BS $60\%$ respectively retarded by as much as $4\~7.5$ hours compared with plain concrete. Plain concrete with HEA WRA, $10\%$ of CKD and RAEWRA had higher strength than that of AE water reducing agent by as much as 5MPa at 28days. From the result of the paper, it is found that the combination of mineral admixture and setting accelerating or retarding agent can reduce the hydration heat cracks by setting time difference and hydration heat reduction effects.

• Geotechnical Engineering
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• v.4 no.1
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• pp.17-28
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• 1988

Among several types of element tests to predict soil behalf.iota in a laboratory, the torsion shear apparatus, in which the directions of principal stresses could be rotated during shearing, wra explained. In this study, this torsion shear apparatus was improved so as to be used in tests on clay specimens . And some undrained torsion shear tests u.ere performed on remolded specimens of Ko-consolidated clay to investigate the influence of reorientation of the principal stress directions on the stress-strain behavior The soil behavior by the torsion shear apparatus without torque was compared It.ith that by the conventional triaxial compression tests . The stress path, provided by both vertical loads and torque during torsion shear tests, has much effect on the stress-strain behavior, the pore pressure and the effective principal stress ratio . The rotation angle of the principal stress and the b-value were gradually increased with increasing shear strain, but converged to the values at failure.

• Food Science and Preservation
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• v.21 no.1
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• pp.82-90
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• 2014

This study was conducted in order to analyze the polyphenol contents and antioxidant activities of hot-water extracts of Aster scaber in the wild field and cultivated field, and through the drying methods for the comparison on the quality characteristics of Aster scaber, according to cultivation and drying methods, and the development of functional materials. The extraction yield was higher in the Aster scaber cultivated field than those of the Aster scaber in the wild field, and high from the dried Aster scaber. The total polyphenol and flavonoid contents of Aster scaber hot-water extracts from the wild field were higher than those in the cultivated field. The total polyphenol contents were high in the extract of blanched and dried Aster scaber, and the flavonoid content was high in the non-treated Aster scaber. The electron donating ability (EDA) values of Aster scaber hot-water extracts were increased along with the increase of extract concentration, while the EDA of the blanched and dried Aster scaber extracts was higher than the other extracts. Furthermore, the SOD-like activity was increased by the extract concentration, and was high in the extract of the non-treated Aster scaber. The nitrite scavenging ability in pH 1.2 was high in the non-treated, blanched, dried, and natural dried Aster scaber. The xanthine oxidase inhibitory activities were increased through the increase of extract concentrations, and higher in the hot-water extract from Aster scaber in the wild field (WRA) than those in the other extracts. The inhibition of tyrosinase and reduction of power were increased by the increased extract concentration, and high in the extracts of blanched and dried Aster scaber. The reduced power was higher in the Aster scaber hot-water extracts of cultivated field, and was higher in the extracts of blanched and dried Aster scaber than those in the extracts dried through the use of other drying methods. Aster scaber has a high content of polyphenol and flavonoid, and antioxidant activities, which were developed as functional materials.