Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Conference Object Citation - Scopus: 1Strength Requirements of Permanent Metal Deck Forms Used for Lateral Bracing of Steel Bridge Girders(2006) Eğilmez, Oğuz Özgür; Helwig, T.A.; Herman, R.S.Permanent metal deck forms (PMDF) are often used in steel bridges to support the weight of the wet concrete during deck construction. Although the PMDF also has the potential to provide bracing to steel bridge girders during construction, the stiffness of the PMDF system as a lateral brace is drastically reduced by the eccentric support angle connection detail used to attach the forms to the girders. Laboratory tests have shown that a simple modification to the connection detail can substantially increase the stiffness of these PMDF systems and allow utilization of the PMDF for girder bracing. This paper presents results from a parametrical study conducted to determine stability and strength requirements for PMDF used to provide lateral bracing to steel bridge girders. Detailed FEA models were used to determine the stability bracing strength requirements for the fasteners that are used to connect the PMDF along the sidelaps of the sheets and to the girders. Design expressions are presented as well as an example demonstrating the use of the design equations.Conference Object Adaptive Actuator Failure Compensation for Cooperating Multiple Manipulator Systems(Elsevier, 2003) Keçeci, Emin Faruk; Tang, Xidong; Tao, GangThis paper presents adaptive actuator failure compensation for a cooperating multiple manipulator system with uncertain actuator failures in the task space. Advantages of designing control schemes in task spaces are emphasized, applications of task space control in robotics are discussed and a short review on control algorithms for cooperating multiple manipulator systems is given. Dynamic equations of motion of the multiple manipulator system in the task space are derived, and the adaptive actuator failure compensation problem is formulated. A compensation controller structure is proposed, for which adaptive parameter update laws are developed. The adaptive control scheme is able to compensate for the uncertainties arising from both the system parameters and the actuator failures. Based on Lyapunov stability analysis, the closed-loop signal boundedness and the convergence of the tracking error to zero are ensured. © 2003 International Federation of Automatic Control.Conference Object Physical Model Experiments of Ordu-Giresun Airport, Turkey(American Society of Civil Engineers (ASCE), 2016) Arıkan, S. E.; Gültekin, N.; Küçükosmanoğlu, A.; Özbahçeci, Bergüzar; Sağ, M.; Kılıç, Y.; Koca, F.Ordu-Giresun Airport, which has been constructed recently, being an example of the aviation sector of Turkish transportation network, is a project having marine structural aspects due to the construction at the sea by filling and in this workout physical model experiments of the project are evaluated. 3000-meters-long runway and the other superstructures of the airport, the first example of construction of such a structure by filling in the sea in Turkey, is to be protected by a breakwater of 7435 meters long. 'First Cross Section' has been prepared by using experimental formulas and artificial neural network and 'Second Cross Section', being the alternative of the first one has been planned. Yet, both cross sections have similar characteristics, they have berm heights in such a manner that 'First Cross Section' enables the structure to be constructed from the sea, whereas 'Second Cross Section' makes it possible from the land. Both cross sections are aimed to be evaluated in terms of stability, wave overtopping and economy through the hydraulic model studies performed at the Hydraulics Laboratory of Turkish Ministry of Transportation, Maritime Affairs and Communication. Starting from design stage (computation of design wave characteristics, physical model experiment under different wave conditions on different structure alternatives) to construction stage the engineering studies is presented with comparisons and discussions.Article Effect of Temperature on Stability of Lipid Microbubbles(Turkish Chemical Society, 2019) Kılıç, SevgiThe effect of temperature on stability of lipid microbubble shell containing polyethyleneoxide-40-stearate (PEG40St) as emulsifier was investigated. Microbubbles at 4 °C were subjected to different temperatures up to 48 ºC (down-to-up) and it was found that both the number and the size of microbubbles remained unchanged in the population up to a certain time, so called “onset time”. The onset time was about 6 hours at 10 °C, 2 hours at 20 °C and shorter at elevated temperatures, exhibiting an exponential decrease with increasing temperature. Once the onset time was reached, the number of microbubbles started to decrease and the average size of the population started to increase. Observation of single microbubbles on a constant temperature heating stage exhibited that each microbubble had its own onset time, with the smaller microbubbles vanishing earlier than the larger ones. The Langmuir monolayer studies showed that hydration degree of the emulsifier PEG chains decreased with temperature, causing them go through conformational changes and subsequently destabilization of the shell. By subjecting the freshly produced microbubbles directly to the desired temperatures in up-to-down fashion, more stable microbubbles were able to be produced, with their onset time increased 40% at 10 °C to 500% at 38 °C. Overall, the results suggest that the new strategies need to be developed to control the collapse process in the microbubble shell resulting from the conformational changes in the PEG chains of the emulsifier for the design of more stable microbubbles. © 2019, Turkish Chemical Society. All rights reserved.