• Proceedings of the Korean Society for Rock Mechanics Conference
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• 2006.03a
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• pp.305-310
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• 2006

• Biomolecules & Therapeutics
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• v.13 no.3
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• pp.150-155
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• 2005

The ethanolic extract of chestnut (Castanea crenata S. et Z., Fagaceae) inner shell (CISE) and one of its components, ellagic acid (EA), were evaluated for their protective effects against 1, 1-diphenyl-2-picryl hydrazine (DPPH) free radical generation and hydrogen peroxide-induced oxidative DNA damage in a mammalian cell line. CISE and EA were shown to possess the free radical scavenging effect against DPPH radical generation, significantly. They were also found to strongly inhibit hydrogen peroxide-induced DNA damage from Chinese hamster lung (CHL) cell, assessed by single cell gel electrophoresis assay and 8-hydroxy -2'-deoxy guanosine (8-OH-2'dG) assay. Furthermore, topical application of CISE [$12.5\%$(w/w) cream] and ellagic acid [$1.0\%$(w/w) cream] for 14 days potently inhibited malondialdehyde (MDA) formation of mouse dorsal skin (a marker of lipid peroxidation) induced by ultraviolet B exposure. Therefore, CISE and its component, ellagic acid, may be the useful natural antioxidants by scavenging free radicals, inhibition of lipid peroxidation and protecting oxidative DNA damage when topically applied.

• International Journal of Industrial Entomology and Biomaterials
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• v.11 no.2
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• pp.119-124
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• 2005

To determine the level of heterosis, higher cocoon shell weight multivoltine congenic lines (Con. L) and bivoltine syngenic lines (Syn. L) of silkworm were used for crosses. First filial generations $(F_1s)$ expressed heterobeltiotic genetic interaction at significant magnitude (p < 0.01) for single cocoon shell weight (SCSW). The other linked characters viz., single cocoon weight (SCW) and yield by weight per 10, 000 larvae were also significantly higher (p < 0.01) than the better parental lines. All the hybrids showed significant improvement for these aforesaid characters over standard heterosis (Standard check). The reeling parameters viz., filament length, raw silk, neatness, cohesionstrokes etc, also showed improvement among the hybrids than check in congenial environment. Overall results suggested that the cross between congenic and syngenic lines provide better heterosis with good quality silk than conventional hybrids and may be used for commercial exploitation.

• Bulletin of the Korean Chemical Society
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• v.35 no.8
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• pp.2367-2370
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• 2014

"Cat's eye"-shaped $[^{57}Co]CoO@SiO_2$ core-shell nanostructure was prepared by the reverse microemulsion method combined with radioisotope technique to investigate a potential imaging agent for a single photon emission computed tomography (SPECT) in nuclear medicine. The core cobalt oxide nanorods were obtained by thermal decomposition of $Co-(oleate)_2$ precursor from radio isotope Co-57 containing cobalt chloride and sodium oleate. The $SiO_2$ coating on the surface of the core cobalt oxide nanorods was produced by hydrolysis and a condensation reaction of tetraethylorthosilicate (TEOS) in the water phase of the reverse microemulsion system. In vivo test, micro SPECT image was acquired with nude mice after 30 min of intravenous injection of $[^{57}Co]CoO@SiO_2$ core-shell nanostructure.

• Wind and Structures
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• v.11 no.6
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• pp.479-496
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• 2008

In this paper, computer simulation of wind flow around a single cooling tower with louver support at the base in the KAZERUN power station in south part of IRAN is presented as a case study. ANSYS FLOTRAN, an unstructured finite element incompressible flow solver, is used for numerical investigation of wind induced pressure load on a single cooling tower. Since the effects of the wind ribs on external surface of the cooling tower shell which plays important role in formation of turbulent flow field, an innovative relation is introduced for modeling the effects of wind ribs on computation of wind pressure on cooling tower's shell. The introduced relation which follows the concept of equivalent sand roughness for the wall function is used in conjunction with two equations ${\kappa}-{\varepsilon}$ turbulent model. In this work, the effects of variation in the height/spacing ratio of external wind ribs are numerically investigated. Conclusions are made by comparison between computed pressure loads on external surface of cooling tower and the VGB (German guideline for cooling tower design) suggestions.

• Structural Engineering and Mechanics
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• v.37 no.3
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• pp.309-320
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• 2011

As a new type of large-span space structure, suspendome is composited of the upper single-layer reticulated shell and the lower cable-strut system. It has better mechanical properties compared to single-layer reticulated shell, and the overall stiffness of suspendome structure increases greatly due to the prestress of cable. Consequently, it can cross a larger span reasonably, economically and grandly with high rigidity, good stability and simple construction. For a better assessment of the advantages of mechanical characteristic of suspendome quantitatively, the static behavior of Kiewitt6 suspendome was studied by using finite element method, and ADINA was the software application to implement the analysis. By studying a certain suspendome, the internal forces, deformation and support constrained forces of the structure were obtained in this paper. Furthermore, the influences of parameters including prestress, stay bar length, cross-sectional area and rise-to-span ratio were also discussed. The results show that the increase of prestress and vertical stay bar length can improve the stiffness of suspendome; Cross-sectional area has nearly no impact on the static behavior, and the rise-to-span ratio is the most sensitive parameter.

• Smart Structures and Systems
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• v.6 no.7
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• pp.767-792
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• 2010

In this paper, the optimal design of vibration control system for smart structures has been investigated semi-analytically via the optimization of geometric parameters like the placements and sizes of piezoelectric sensors and actuators (S/As) bonded on the structures. The criterion based on the maximization of energy dissipation was adopted for the optimization of the control system. Based on the sensing and actuating equations, the total energy stored in the system which is used as the objective function was analytically derived with design variables explicitly presented. Two cases of single and combined vibration modes were addressed for a simply supported beam and a simply supported cylindrical shell. For single vibration mode, the optimal distributions of the piezoelectric S/As could be obtained analytically. However, the Sequential Quadratic Programming (SQP) method has to be employed to solve those which violated the prescribed constraints and to solve the case of combined vibration modes. The results of three examples, which include a simply supported beam, a simply supported cylindrical shell and a simply supported plate, showed good agreement with those obtained by the Genetic Algorithm (GA) method. Moreover, in comparison with the GA method, the proposed method is more effective in obtaining better optimization results and is much more efficient in terms of computation time.

• The Korean Journal of Malacology
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• v.27 no.2
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• pp.143-148
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• 2011

Even though ark shell, Scapharca broughtonii is commercially important species, its artificial seed production is not yet fully developed. This study was carried out to understand the effect of three microalgal species on gonadal development and sex maturation of S. broughtonii in terms of broodstock management and food organism. Isochrysis galbana, Phaeodactylum tricornutum and Tetraselmis tetrathele were supplied to S. broughtonii broodstock in single or mixed. And condition index, gonadal development, sexual maturation and survival of the broodstock were analysed. After 45 rearing days, frequency of ripe stage of gonadal phases, rate of induced sexual maturation and survival of S. broughtonii broodstock fed mixed diet with 3 microalgal species or single diet of T. tetrathele were the highest.

• Journal of the Korean Magnetics Society
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• v.25 no.1
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• pp.10-15
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• 2015

The model for the magneto-impedance of composite wires composed of highly conductive nonmagnetic metal core and soft magnetic shell was derived based on the Maxwell's equations. The Cu($100{\mu}m$ diameter)/$Ni_{80}Fe_{20}$($15{\mu}m$ thickness) core/shell composite wire was fabricated by electrodeposition. The impedance spectra for the $Cu/Ni_{80}Fe_{20}$ core/shell composite wire were measured in the frequency range of 10 kHz~10 MHz under longitudinal dc magnetic field in 0 Oe~200 Oe. The spectra of complex permeability in circumferential direction were extracted from the impedance spectra by using the derived model. The extracted spectra of complex permeability showed relaxation-type dispersion which is well curve-fitted with Debye equation with single relaxation frequency. By analyzing the magnetic field dependence of the complex permeability spectra, it has been verified that the composite wire has magnetic anisotropy in longitudinal direction and the origin of the single relaxation process is the magnetization rotation in circumferential direction.

• Journal of Nutrition and Health
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• v.45 no.5
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• pp.429-436
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• 2012

This study was performed to examine the characteristics of protein of red crab (Chionoecetes japonicus) shell powder hydrolyzed by commercial proteases. Red crab shell was digested by commercial proteases, such as Protamex (P), Neutrase (N), Flavourzyme (F), Alcalase (A), Protease M (PM) and Protease A (PA). Protein yield analyzed by Biuret assay, absorbance at 280 nm and brix revealed that PA was the enzyme having the highest proteolytic activity. SDS PAGE showed that molecular weight of proteins produced by protease treatments was various and below 150 kDa. Combinational treatment of proteases (PA + P, PA + PM, PA + F, PA + A) was tried whether these increase protein hydrolysis from red crab shell powder compared to a PA single treatment. Soluble protein content was similar, but amino acid concentration by combinational treatments was higher than PA single treatment [PA + P 247.4 mg/g > PA + F (206.4 mg/g) > PA + A (133.4 mg/g) > PA + PM (59.1 mg/g) > PA (54.9 mg/g)]. Amino acid composition by combinational treatments was slightly different. Most abundant essential amino acids were phenylalanine, glycine, alanine, and leucine, whereas tyrosine and cystine were not detected.