• Journal of the Korean Society for Railway
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• v.9 no.6 s.37
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• pp.689-694
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• 2006

Most of design parameters of Railway Structures are determined by the serviceability requirements, rather than the structural safety requirements. The serviceability requirements come from Ensuring of running safety and ride comfort of train, reduction of track maintenance working Track-Bridge interaction should be considered in the design of railway structures. In this study, a numerical method which precisely evaluate an axial force of rail and a rail expansion and contraction when turnout exist in succession on a CWR of bridge is developed.

• Structural Engineering and Mechanics
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• v.45 no.5
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• pp.655-676
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• 2013

In this study, strength reduction factors and inelastic displacement ratios are investigated for SDOF systems with period range of 0.1-3.0 s considering soil structure interaction for earthquake motions recorded on soft soil. The effect of stiffness degradation on strength reduction factors and inelastic displacement ratios is investigated. The modified-Clough model is used to represent structures that exhibit significant stiffness degradation when subjected to reverse cyclic loading and the elastoplastic model is used to represent non-degrading structures. The effect of negative strain - hardening on the inelastic displacement and strength of structures is also investigated. Soil structure interacting systems are modeled and analyzed with effective period, effective damping and effective ductility values differing from fixed-base case. For inelastic time history analyses, Newmark method for step by step time integration was adapted in an in-house computer program. New equations are proposed for strength reduction factor and inelastic displacement ratio of interacting system as a function of structural period($\tilde{T}$, T) ductility (${\mu}$) and period lengthening ratio ($\tilde{T}$/T).

• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1262-1266
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• 2009

Thermodynamics of the interaction between Cerium (III) chloride, $Ce^{3+}$, with Human Serum Albumin, HSA, was investigated at pH 7.0 and $27\;{^{\circ}C}$ in phosphate buffer by isothermal titration calorimetry. Our recently solvation model was used to reproduce the enthalpies of HSA interaction by $Ce^{3+}$. The solvation parameters recovered from our new model, attributed to the structural change of HSA and its biological activity. The interaction of HSA with $Ce^{3+}$ showed a set of two binding sites with negative cooperativity. $Ce^{3+}$ interacts with multiple sites on HSA affecting its biochemical and biophysical properties.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.527-535
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• 1997

Vapor-liquid equilibrium apparatus is designed and set up. The vapor-liquid equilibrium data of the binary system HFC32/134a are measured in the range between 258.15 and 283.15K at compositions of 0.2, 0.4, 0.6 and 0.8 mole fraction of HFC32. Twenty-two equilibrium data are obtained. Based upon the present data, the binary interaction parameter for Carnahan-Starling-De Santis equation of state is calculated. Temperature range of data is extended to 313.04K using the data in the open literatures. Interaction parameters are determined at nine isotherms.

• Wind and Structures
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• v.6 no.1
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• pp.41-52
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• 2003

Rain-wind induced vibrations of cables are a challenging problem in the design of cable-stayed bridges. The precise excitation mechanism of the complex interaction between structure, wind and rain is still unknown. A theoretical model that is able to accurately simulate the observed phenomena is not available. This paper presents a mathematical model describing rain-wind induced vibrations as movement-induced vibrations using the quasi-steady strip theory. Both, the vibrations of the cable and the movement of the water rivulet on the cable surface can be described by the model including all geometrical and physical nonlinearities. The analysis using the stability and bifurcation theory shows that the model is capable of simulating the basic phenomena of the vibrations, such as dependence of wind velocity and cable damping. The results agree well with field data and wind tunnel tests. An extensive experimental study is currently performed to calibrate the parameters of the model.

• Ocean Systems Engineering
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• v.7 no.2
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• pp.89-106
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• 2017

The study explores a novel design of wave energy converter (WEC) that utilizes the interaction between an inside heaving vertical cylinder with an outside fixed hollow cylinder. This design originates from the oscillating water column (OWC) type WEC but replaces the pneumatic power take off (PTO) through the Wells turbine with the hydrodynamic PTO through the inside heaving cylinder. To effectively evaluate the maximum power output, the system has been modeled in the hydrodynamic software AQWA (developed by ANSYS Inc) that has accumulated extensive offshore industry users. Ranges of the PTO parameters have been examined to make sure that proper linear damping can be implemented to simulate the PTO force. Comparing the efficiency of the pneumatic PTO with the hydrodynamic PTO, it appears that the hydrodynamic PTO is more promising than the traditional Wells turbine for an OWC system.

• Structural Engineering and Mechanics
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• v.23 no.5
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• pp.563-577
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• 2006

This study involves a series of experiments on the buckling strength of eccentrically compressed cold-formed stainless steel square hollow-section columns. The principal parameters in this study are slenderness ratios ($L_k/r$ = 30, 50, 70) and magnitude of eccentricity e (0, 25, 50, 75, 100 mm) on the symmetrical end-moment. The objectives of this paper are to obtain the buckling loads by conducting a series of experiments and to compare the behavior of the eccentrically compressed cold-formed stainless steel square hollow-section columns with the results of the analysis. The ultimate buckling strength of the square-section members were determined with the use of a numerical method in accordance with the bending moment-axial force (M-P) interaction curves. The behavior of each specimen was displayed in the form of a moment-radian (M-${\theta}$) relationship. The numerically obtained ultimate-buckling interaction curves of the beam columns coincided with the results of the experiments.

• Earthquakes and Structures
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• v.13 no.1
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• pp.39-50
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• 2017

Displacement response and corresponding maximum response energy of structures are key parameters to assess the dynamic effect or even more destructive structural damage of the structures. By employing them, this research has compared the structural responses of jacket supported offshore wind turbine (OWT) subjected to seismic excitations apprehending earthquake incidence, when (a) soil-structure interaction (SSI) has been ignored and (b) SSI has been considered. The effect of earthquakes under arbitrary angle of excitation on the OWT has been investigated by means of the energy based wavelet transformation method. Displacement based fragility analysis is then utilized to convey the probability of exceedance of the OWT at different soil site conditions. The results show that the uncertainty arises due to multi-component seismic excitations along with the diminution trend of shear wave velocity of soil and it tends to reduce the efficiency of the OWT to stand against the ground motions.

• Textile Coloration and Finishing
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• v.24 no.4
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• pp.239-246
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• 2012

The binding isotherms of ionic dyes with Poly(vinylpyrrolidone) in aqueous solution were determined by the dynamic dialysis technique. The shape of the isotherms of cationic dye, C. I. Basic Red 18 with poly(vinlypyrrolidone) showed a partition type. It suggests that the binding involves a non-cooperative mode. Isotherms of an anion dye, a synthesized dye by coupling of diazotized m-trifluoromethylaniline with 2-naphthol-6-sulfonic acid, were sigmoid type and showed multimode interaction. The results were interpreted by the McGhee von Hippel theory. The thermodynamic parameters for the complex formation of the dyes-polymer were calculated from their temperature dependences of the intrinsic binding constant.

• Bulletin of the Korean Chemical Society
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• v.4 no.2
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• pp.87-91
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• 1983

Molecular dynamic method has been applied to a single polymer chain immersed in a solvent. The interactions for the pairs, of two solvent molecules (SS), of a chain element and a solvent molecules (CS), and of two non-neighbor chain elements (CC) are given by the Lennard-Jones potential, and the interaction between two bonded chain elements is given by a harmonic potential. We changed the CS interaction parameter ${\varepsilon}_{CS}$ to 0.5, 1.0 and 2.0 times of the SS interaction ${\varepsilon}_{SS}$. We calculated the pair correlation functions for the SS, CS, and CC pairs, end-to-end distance and radius of gyration with the varying ${\varepsilon}_{CS}$ parameters. The results showed that a phase separation occurs between the polymer and solvent in the 0.5 system where ${\varepsilon}_{CS}$ = 0.5 {\varepsilon}_{SS}$. The autocorrelation functions for end-to-end distance and radius of gyration were also calculated.