• Earthquakes and Structures
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• v.2 no.2
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• pp.127-147
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• 2011

In a companion paper as well as in earlier publications, it has been shown that in asymmetric frame buildings, designed in accordance with modern codes and subjected to strong earthquake excitations, the ductility demands at the so called "flexible" edges are consistently and substantially higher than the ductility demands at the "stiff" edges of the building. In some cases the differences in the computed ductility factors between elements at the two opposite building edges exceeded 100%. Similar findings have also been reported for code designed reinforced concrete buildings. This is an undesirable behavior as it indicates no good use of material and the possibility for overload of the "flexible" edge members with a consequent potential for premature failure. In the present paper, a design modification will be introduced that can alleviate the problem and lead to a more uniform distribution of ductility demands in the elements of all building edges. The presented results are based on the steel frames detailed in the companion paper. This investigation is another step towards more rational design of non-symmetric steel buildings.

• International Journal of Knowledge Content Development & Technology
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• v.8 no.2
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• pp.23-36
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• 2018

Institutional repositories (IR) are promising to be extremely advantageous to scholars especially in developing countries. IR initiatives started in India during the late nineties and the popularity of this concept is growing rapidly in the higher educational and research institutions to disseminate newly emerging knowledge and expertise. The purpose of this paper is to critically analyze the network links of IR websites among four IITs that are registered in open DOAR (Directory of Open Access Repositories) web portal. The Institutional Repositories chosen for the study are IIT Delhi, IIT Hyderabad, IIT Bombay, and IIT Kanpur. The analysis of the study focused on standard graph and network cohesion metrics, such as density, diameter, eccentricity and distances, and clustering coefficient; for an even more detailed analysis advanced centrality measures and fast algorithms such as clique census are used.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.33-36
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• 2006

The purpose of this paper is to investigate the structural behavior of fire damaged high-strength SRC columns with polypropylene fiber. When high-strength concrete is exposed to high temperature, spalling is occurred then it leads to decrease the capacity of members. Polypropylene fiber is used to reduce the spalling of the specimens and the distinction in the behavior after fire is observed. High-strength concrete specimens were exposed to high temperatures by the ISO 834 curve. Main experimental parameters were the ratio of the contained polypropylene fiver, heating time and type of loading. Reduction rate in residual strength and stiffness is observed for the mixing of PP fiber, the heating time and eccentricity of loading.

• Journal of Biomedical Engineering Research
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• v.15 no.1
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• pp.77-82
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• 1994

We investigated the characteristic of the sensory motor coordination by measuring the hand point ins and the gaze movement to the visual and sound stimulation. Our results showed that the gaze vol ocity to sound stimulation did not depend on stimulation direction, but lagged behind 0.2 sec toward the pheriperal direction to the visual stimulation. Our data showed that to both visual and sound stimulation, the error of hand pointing value increased with an increasement of eccentricity.

• Steel and Composite Structures
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• v.8 no.5
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• pp.423-438
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• 2008

This paper reports an experimental investigation of the behaviour of concrete-encased composite columns subjected to short-term axial load and biaxial bending. In the study, six square and four L-shaped cross section of both short and slender composite column specimens were constructed and tested to examine the load-deflection behaviour and to obtain load carrying capacities. The main variables in the tests were considered as eccentricity of applied axial load, concrete compressive strength, cross section, and slenderness effect. A theoretical procedure considering the nonlinear behaviour of the materials is proposed for determination of the behaviour of eccentrically loaded short and slender composite columns. Two approaches are taken into account to describe the flexural rigidity (EI) used in the analysis of slender composite columns. Observed failure mode and experimental and theoretical load-deflection behaviour of the specimens are presented in the paper. The composite column specimens and also some composite columns available in the literature have been analysed and found to be in good agreement with the test results.

• Earthquakes and Structures
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• v.13 no.1
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• pp.9-15
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• 2017

In this paper, the influence of the rotational component, about a vertical axis, of earthquake ground motion on the response of building structures subjected to seismic action is considered. The torsional component of ground motion is generated from the records of translational components. Torsional component of ground motion is then, together with translational components, applied in numerical linear dynamic analysis of different reinforced concrete framed structure of three stories buildings. In total, more than 40 numerical models were created and analyzed. The obtained results show clearly the dependence of the effects of the torsional seismic component on structural system and soil properties. Thus, the current approach in seismic codes of accounting for the effects of accidental torsion due to the torsional ground motion, by shifting the center of mass, should be reevaluated.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2146-2148
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• 2003

This paper present a modified repetitive control scheme for an optical storage system to track a periodic reference signal with dynamic change in period. Periodic disturbances can be adequately attenuated using the concept of repetitive control, provided the period is know. An optical storage system supports various speeds. To deal with time varying periodic disturbances, an proposed repetitive controller is turned based on repetitive control to change sampling frequency to follow the change of reference Period. A modified repetitive control scheme is proposed and implement on experimental set up of a optical disk driver.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.80-87
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• 1998

In this study, the effects of residual shaft bow and flexible bearings of a single disk rotor are investigated. The stiffness coefficients of a shaft with initial deflection are different from those of a straight shaft. The stiffness coefficients are calculated using Castigliano theorem considering initial deflections. The stiffness coefficients, which are obtained in this study, are in good agreement with FEM results. The speed which causes zero amplitude is shown to be the square root of the ratio of residual bow amplitude to unbalance eccentricity in the case of rigid bearings and isotropic flexible bearings, but not in anisotropic bearings.

• 연구논문집
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• s.24
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• pp.175-188
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• 1994

Water seal is composed of metal case, garter spring, and NBR. Axisymmetric, large deformation non-linear contact problems were solved by using the finite element method for the evaluation of performance of the water seal. Effects of the interference between seal and shaft, and the garter spring on the seal characteristics were considered in this analysis. The contact force and sealing performance increased as the interference and spring stiffness increases. And middle seal is main role sealing performance. Further research efforts are required to consider the effects of the garter spring stiffness, the eccentricity by the shaft or case, and the water pressure.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1057-1058
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• 2007

This paper proposes an alternative vibration detection method in a squirrel-cage induction motor using flux sensors. The air-gap flux will be changed when mechanical vibration occurs by bearing fault as well as broken rotor bar and air-gap eccentricity. For detecting those flux variations due to vibration, search coils are installed at stator slots. The induction motor with 380 [V], 7.5 [kW], 4 [Poles], 1,760 [rpm] ratings is used. Magnitudes and distortion of the induced voltage from flux sensors are used to discriminate faulted types. As a result, the flux sensor has been proven to be useful for vibration detection. It is compared to the result with vibration sensor as well.