• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.1
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• pp.130-140
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• 2007

Fiber-sheet and steel-plate strengthening methods have been mainly used for strengthening the RC structures. However, recently the application of these two methods have dramatically decreased due to premature debonding failure between concrete surface and fiber-sheet and heavy self-weight of steel-plate. This article presents experimental results of shear behavior in RC beams strengthened with GSP(Glass fiber-Steel composite Plate). The thin steel plate in GSP makes usage of the anchoring system possible, which could delay or prevent the premature debonding failure. Three reference beams and 60 strengthened beams with GSP were tested. The experimental results showed that strengthened beams with GSP considerably increased in shear capacity compared with the reference beams.

• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.135-139
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• 2006

Most bacteria form biofilm as self-defence system, making efficient food sanitization, preservation, and instrument washing more difficult. Biofilm formation of Salmonella, E. coli, B. cereus, and S. aureus was observed during 24 hr food preservations by performing microtiter plate and glass wool assays. Most cells formed biofilm and attached onto glass wool. When biofilm formation and injury were analyzed on the microtiter plate, 10 and 20% acid-injured E. coli and S. aureus, respectively, 30-50% cold temperature $(4^{\circ}C)-injured$ B. cereus and E. coli, and 30-55% 6% sodium chloride solution-injured Salmonella showed significant biofilm formation. Results indicate biofilm formation level differed within species depending on type of stress.

• Korean Journal of Optics and Photonics
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• v.6 no.2
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• pp.130-134
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• 1995

A small signal gain coefficient of Nd:glass was measured and a cavity-dumped laser was constructed. To measure the small signal gain coefficient, we constructed a resonator consisting of Nd:glass, Pockels cell, polarizing beam splitter. The measured small signal gain coefficient was $0.088 cm_{-1}$ when the input energy was 100 J and the round-trip internal loss of the resonator was 56%. The cavity-dumped laser was constructed using Nd:glass. 2 m radius of curvature HR-mirrors, Pockels cell, polarizinig beam splitter and $\lambda/4$ plate. The output energy of cavity-dumped laser was 0.85 J at 140 J input energy and the laser pulse width was 8 ns.s 8 ns.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.6
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• pp.1781-1791
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• 1991

For the cracked plate under transient temperature distribution, J-integral is expressed in the form of line integral by using convolution integral. The J$_{1}$ integral is calculated for a through line center cracked steel plate under thermal and mechanical loading conditions and the calculated values are in good agreement with previous results. The effect of inertia term on the J$_{1}$ integral is not negligible for a glass but for a steel. For the glass plate, the rates of J$_{1}$ integral value to time increase if the values of material properties such as specific heat, thermal conductivity, thermal diffusivity and Young`s modulus as well as crack length and temperature difference in cracked edge increase.

• Structural Engineering and Mechanics
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• v.85 no.5
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• pp.573-592
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• 2023

This paper presents a careful theoretical investigation into interfacial stresses in composite aluminum-slab reinforced concrete beam bonded by a prestressed hybrid carbon-glass composite material. The model is based on equilibrium and deformations compatibility requirements in and all parts of the strengthened beam, i.e., the aluminum beam, the slab reinforced concrete, the hybrid carbon-glass composite plate and the adhesive layer. The theoretical predictions are compared with other existing solutions. Numerical results from the present analysis are presented both to demonstrate the advantages of the present solution over existing ones and to illustrate the main characteristics of interfacial stress distributions. It is shown that the stresses at the interface are influenced by the material and geometry parameters of the composite beam. This research is helpful for the understanding on mechanical behaviour of the interface and design of the hybrid structures.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.103-106
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• 2009

Fracture characteristics of plate shape using shock tube for glass filled ceramics was carried out. Glass filled ceramics have been considered as a promising candidate material for the dome port cover of air breathing engine. This part of the air breathing engine has an important role separating solid and liquid fuel, and needs the frangible characteristics that the fracture of a part should not affect the internal components of combustion. The objectives of this study are to evaluate the fracture pressures for various thicknesses and diameters of shock impact area. Also fracture phenomena of separated membrane using a shock tube are observed. The experimental apparatus of shock tube consists of a driver, a driven section and a dump tank. The used material is glass filled ceramic made from Corning company. Specimens are used 3, 4.5 and 6mm thickness. Also diameters of shock wave area are chosen 70, 60 and 50 mm. It is expected that the results obtained from this study can be used in the basic data for the dome port cover design of an air breathing engine.

• Structural Engineering and Mechanics
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• v.74 no.5
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• pp.671-678
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• 2020

In this work, the dynamic properties of a high performance concrete containing glass powder (GP) was studied. The GP is a new cementitious material obtained by recycling waste glass presenting pozzolanic activity. This eco-friendly material was incorporated in concrete mixes by replacing 20 and 30% of cement. The mechanical properties of building materials highly affect the response of the structure under dynamic actions. First, the resonant vibration frequencies were measured on concrete plate with free boundary conditions after 14, 28 and 90 curing days by using an alternative vibration monitoring technique. This technique measures the average frequencies of several excitations done at different points of the plate. This approach takes into account the heterogeneity of a material like concrete. So, the results should be more precise and reliable. For measuring the bending and torsion resonant frequencies, as well as the damping ratio. The dynamic properties of material such as dynamic elastic modulus and dynamic shear modulus were determined by modelling the plate on the finite element software ANSYS. Also, the instantaneous aroused frequency method and ultrasound method were used to determine the dynamic elastic modulus for comparison purpose, with the results obtained from vibration monitoring technique.

• Structural Engineering and Mechanics
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• v.65 no.4
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• pp.369-380
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• 2018

In this paper, a multi-layered finite element model for laminated glass plates is introduced. A layer-wise theory is applied to the analysis of laminated glass due to the combination of stiff and soft layers; the independent layers are connected via Lagrange multipliers. The von $K{\acute{a}}rm{\acute{a}}n$ large deflection plate theory and the constant Poisson ratio for constitutive equations are assumed to capture the possible effects of geometric nonlinearity and the time/temperature-dependent response of the plastic foil. The linear viscoelastic behavior of a polymer foil is included by the generalized Maxwell model. The proposed layer-wise model was implemented into the MATLAB code and verified against detailed three-dimensional models in ADINA solver using different hexahedral finite elements. The effects of temperature, load duration, and creep/relaxation are demonstrated by examples.

• Genomics & Informatics
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• v.4 no.3
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• pp.133-136
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• 2006

The adsorption of proteins on the surface of glass slides is essential for construction of protein chips. Previously, we prepared a nickel-coated plate by the spin-coating method for immobilization of His-tagged proteins. In order to know whether the structural factor is responsible for the immobilization of His-tagged proteins to the nickel-coated glass slide, we executed a series of experiments. First we purified a His-tagged protein after expressing the vector in E. coli BL21 (DE3). Then we obtained the unfolding curve for the His-tagged protein by using guanidine hydrochloride. Fractions unfolded were monitored by internal fluorescence spectroscopy. The ${\Delta}G_{H20}$ for unfolding was $2.27kcal/mol{/pm}0.52$. Then we tested if unfolded His-tagged proteins can be adsorbed to the nickel-coated plate, comparing with $Ni^{2+}-NTA$ (nitrilotriacetic acid) beads. Whereas unfolded His-tagged proteins were adsorbed to $Ni^{2+}-NTA$ beads, they did not bind to the nickel-coated plate. In conclusion, a structural factor is likely to be an important factor for constructing the protein chips, when His-tagged proteins will immobilize to the nickel-coated slides.

• Journal of the Korean Solar Energy Society
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• v.33 no.3
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• pp.36-41
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• 2013

The reflection plate in twin-glass evacuated tube solar collector is controlled to reduce the overheat during the summer time. The sliding type and folding types are suggested and tested. The sliding type changes the plate angle and the folding type changes the opening angle of the reflection plate. By scattering the focus of the reflected radiation from the reflection plate, the temperature rise of the working fluid can be reduced. The sliding type shows the best results in overheat reduction. When solar radiation is 900 $W/m^2$, the temperature rise in one sliding type collector is reduced about $2^{\circ}C$ compared to that of the normal solar collector. When this method is applied to seven series-collectors in the field, the reduction of temperature rise during the summer time should be significant.