• Journal of Astronomy and Space Sciences
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• v.15 no.1
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• pp.49-52
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• 1998

We show quantitatively whether giant elliptical galaxies would be visible at for UV wavelenghts if they were placed at moderate red shift of 0.4-0.5. On the basis of simple cosmological tests, we conclude that giant elliptical galaxies can be detectable up to the red shift of 0.4-0.5 in the proposed GALEX(Galaxy Evolution Explorer) Deep Imaging Survey. We also show that obtaining UV color index such as $m_{1550}$ - V from upcoming GALEX and SDSS (Sloan Digital Sky Survey) observations should be feasible.

• Structural Engineering and Mechanics
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• v.39 no.3
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• pp.303-316
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• 2011

Experimental tests have shown that glass exhibits very different strengths when tested under biaxial and uniaxial conditions. This paper presents a study on the effects of biaxial stresses on the notional ultimate strength of glass. The study involved applying the theory of elasticity and finite element analysis of the Griffith flaw in the micro scale. The strain intensity at the tip of the critical flaw is used as the main criterion for defining the limit state of fracture in glass. A simple and robust relationship between the maximum principal stress and the uniaxial stress to cause failure of the same glass specimen has been developed. The relationship has been used for evaluating the strength values of both new and old annealed glass panels. The characteristic strength values determined in accordance with the test results based on 5% of exceedance are compared with provisions in the ASTM standard.

• Proceedings of the KIPE Conference
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• 2004.07b
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• pp.914-917
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• 2004

This paper presents a design and characteristics analysis of a SRM drive for EPS application. A rack mounted EPS system is considered in this paper. A conventional driving room space and mechanical structure are suggested in design stage. In the restricted design conditions, motor parameters are determined for sufficient torque and speed. For the smooth torque generation and simple circuit of power system, 12/8 motor drive is considered. With FEM and magnetic circuit analysis, designed motor is simulated to meet the requirement of specifications. Effectiveness of the suggested SRM drive for EPS application is verified by the manufactured prototype motor drive tests.

• Proceedings of the KIPE Conference
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• 2004.07a
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• pp.58-60
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• 2004

This paper presents a design and characteristics analysis of an SRM drive for EPS application. A rack mounted EPS system is considered in this paper. In the unrestricted design conditions, motor parameters are determined for sufficient torque and speed with some restrictions. For the smooth torque generation and simple circuit of power system, 12/8 motor drive is considered. With FEM and magnetic circuit analysis, redesigned motor is simulated to meet the requirement of specifications. Effectiveness of the suggested SRM drive for EPS application is verified by redesigned motor drive tests.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.12
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• pp.587-594
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• 2003

This paper presents a design and characteristic analysis of an SRM drive for EPS(Electrically Power Steering) application. A rack mounted EPS system is considered in this paper. A conventional driving room space and mechanical structure are considered in a design stage. In the restricted design conditions, motor parameters are determined for sufficient torque and speed. For the smooth torque generation and simple circuit of power system, 12/8 motor drive is considered. With FEM and magnetic circuit analysis, designed motor is simulated to meet the requirement of specifications. Effectiveness of the suggested SRM drive for EPS application is studied by the drive tests of a prototype motor.

• Transactions of Materials Processing
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• v.10 no.3
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• pp.206-213
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• 2001

Dynamic deformation of metallic materials mostly accompanies substantial amounts of deformation heat. Since the flow stress of deformation is sensitive to temperature, implication of heat due to plastic work is essential to the evaluation of constitutive relations. In this study, a series of compression tests were conducted for SAF 2507 super duplex stainless steel at various temperatures and strain rates. The accumulation of plastic work was calculated through numerical integration and converted into the elevation of temperature. Subsequent logarithmic interpolation deduced isothermal flow surfaces, which were primary input data of finite element analysis. Simple closed die forging process was analyzed and optimized with commercial FEM code applying both raw and calibrated material database. The effect of accounting deformation heat was more noticeable in high-speed forming process.

• International Journal of Control, Automation, and Systems
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• v.3 no.spc2
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• pp.288-295
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• 2005

In this paper a new adaptive, decentralized excitation control scheme proposed to enhance the transient stability of multimachine power systems is extensively analyzed with respect to its robustness and disturbance attenuation. As shown in the paper, both robustness and disturbance attenuation can be effectively improved by suitably selecting the design parameters of the proposed controller. Particularly, some simple rules for the selection of the control gains and the adaptation parameters are extracted which, as it is proven, may be essential for the system performance. Simulation tests on a two generator infinite bus power system absolutely confirm the theoretical results.

• Structural Engineering and Mechanics
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• v.21 no.2
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• pp.221-235
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• 2005

In this paper, the shear resistance behaviour of reinforced concrete (RC) dapped end beams is investigated by 24 tests until failure load. The main parameters considered are the dapped end height, the type and effective range to provided the stirrups and the bent form of the longitudinal reinforcement. The failure behaviour of dapped end beams is presented and some conclusions are given. Inclined stirrups and longitudinal bent reinforcement have more influence on the shear capacity than vertical stirrups. Additionally, the shear mechanism of dapped end beams is analysed. Relatively simple semi-empirical equations for shear strength have been derived based on the results of 22 dapped end beams. The predicted results are in close agreement with the experimental ones. Finally, some design suggestions for the ultimate shear strength of dapped end beams are presented.

• Structural Engineering and Mechanics
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• v.23 no.6
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• pp.713-737
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• 2006

This paper presents the results of an experimental investigation on the behaviour of 56 reinforced concrete beams subjected to pure torsion. The reported results include the behaviour curves, the failure modes and the values of the pre-cracking torsional stiffness, the cracking and ultimate torsional moments and the corresponding twists. The influence of the volume of stirrups, the height to width ratios and the arrangement of longitudinal bars on the torsional behaviour is discussed. In order to describe the entire torsional behaviour of the tested beams, the combination of two different analytical models is used. The prediction of the elastic till the first cracking part is achieved using a smeared crack analysis for plain concrete in torsion, whereas for the description of the post-cracking response the softened truss model is used. A simple modification to the softened truss model to include the effect of confinement is also attempted. Calculated torsional behaviour of the tested beams and 21 beams available in the literature are compared with the experimental ones and a very good agreement is observed.

• Geotechnical Engineering
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• v.13 no.2
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• pp.55-64
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• 1997

Laboratory tests were performed to desorb organic contaminants spiked onto soil particles by using surfactants. Nonionic and anionic surfactants were tested as potential desorbing solvents for extracting quinoline and 2-napthol adsorbed on soil particles. Ahionisc stirfactant remediated approximately 80% and 90% of quinoline and 2-napthol respectively and appeared to be more effective than nonionic surfactant in remediating those compounds, Comparison between simple deionized water washing of the organic contaminated soil and a given surfactant technique evaluated the improvement by the application of a Burfactant to the promotion of desorption.