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Istanbul, Turkey

Istanbul Technical University is an international technical university located in Istanbul, Turkey. It is the world's third oldest technical university dedicated to engineering science as well as social science recently, and is one of the most prominent educational institutions in Turkey. ITU is ranked 108th worldwide and 1st nationwide in the field of engineering/technology by THES - QS World University Rankings in 2009. Graduates of İstanbul technical university have received many TUBITAK science and TUBA awards. Numerous graduates have also become members of the academy of science in the U.S.A, Britain and Russia. The university's basketball team, ITUSpor, is in the Turkish Basketball Second League. The university has 39 undergraduate, 144 graduate programs, 13 colleges, 346 labs and 12 research centers. Its student-to-faculty ratio is 12:1. Wikipedia.

Yesil E.,Technical University of Istanbul
Applied Soft Computing Journal

This paper proposes an optimization based design methodology of interval type-2 fuzzy PID (IT2FPID) controllers for the load frequency control (LFC) problem. Hitherto, numerous fuzzy logic control structures are proposed as a solution of LFC. However, almost all of these solutions use type-1 fuzzy sets that have a crisp grade of membership. Power systems are large scale complex systems with many different uncertainties. In order to handle these uncertainties, in this study, type-2 fuzzy sets, which have a grade of membership that is fuzzy, have been used. Interval type-2 fuzzy sets are used in the design of a load frequency controller for a four area interconnected power system, which represents a large power system. The Big Bang-Big Crunch (BB-BC) algorithm is applied to tune the scaling factors and the footprint of uncertainty (FOU) membership functions of interval type-2 fuzzy PID (IT2FPID) controllers to minimize frequency deviations of the system against load disturbances. BB-BC is a global optimization algorithm and has a low computational cost, a high convergence speed, and is therefore very efficient when the number of optimization parameters is high as presented in this study. In order to show the benefits of IT2FPID controllers, a comparison to conventional type-1 fuzzy PID (T1FPID) controllers and conventional PID controllers is given for the four-area interconnected power system. The gains of conventional PID and T1FPID controllers are also optimized using the BB-BC algorithm. Simulation results explicitly show that the performance of the proposed optimum IT2FPID load frequency controller is superior compared to the conventional T1FPID and PID controller in terms of overshoot, settling time and robustness against different load disturbances. © 2013 Elsevier B.V. All rights reserved. Source

Tunca U.,Technical University of Istanbul
Macromolecular Rapid Communications

This Feature Article focuses on the rapidly emerging concept of the "triple click reactions" towards the design and synthesis of macromolecules with well-defined topology and chemical composition, and also precise molecular weight and narrow molecular weight distribution. The term "triple click reaction" used in this feature article is based on the utilization of three chemically and mechanistically different click reactions for polymer-polymer conjugation and post-modification of the polymers. Three sequential click reactions of which two are identical should not be considered to be triple click reactions. The triple click reaction strategy for polymer conjugation and post-modification of polymers is classified in this article based on the resultant architectures: linear and non-linear structures. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Major discrepancy between present-day fault models in the Marmara Sea is closely related to structural development of depression areas beneath the sea. Therefore, in this study, the Marmara Sea and especially its major basins are investigated by means of recent seismological observations consisting of microseismicity (1.2 ≤Md≤ 3.6; 2002 May-2006 May), focal mechanisms (2.4 ≤Md≤ 5.0; 1999-2006) and stress analysis based on the focal mechanisms. In the Çinarcik Basin where either pull-apart model or negative flower structure is proposed, northeastern margin is represented by strike-slip sources having a NW alignment, probably corresponding to a cross-basin strike-slip fault developing in a matured pull-apart basin. This suggestion is directly relevant to experiments of sand box analogue models. These experiments indicate that such a cross-basin strike-slip fault is produced after the pull-apart basins attain their mature stage, eventually resulting in less vertical displacements attributed to normal faults bounding the basin. This experimental decline may be corroborated by the paucity of normal mechanisms in the basin. Extensional motion in this region is more influential outside of the basin, especially to the area where an onshore seismic activity is monitored on the land. On the other hand, another strike-slip activity in the Çinarcik Basin is distributed on a possible strand, parallel to the northern coastline of the Marmara Sea in the Armutlu Peninsula. This may indicate that one or more short strands of the northern splay extend to the west by bounding the basin from the south. In the Central Basin, the existence of a right-lateral strike-slip faulting on an east-west trending fault is supported by similar strike-slip focal mechanisms located at both extremities of the basin. To the west, dominant style of deformation gradually shifts from strike-slip faulting to transpression along the western coastline of the Marmara Sea where the northern splay joins with the offshore continuation of the Ganos Fault. Finally, focal mechanisms in the Marmara Sea are inverted for the best fitting stress tensor, characterized by a subvertical σ2-axis and two subhorizontal stress axes of σ1 and σ3, oriented NW-SE and NE-SW, respectively. Conclusively, this study infers that the current tectonics of the Marmara Sea is mainly governed by a strike-slip regime, ascribed to both submarine splays of the NAF, and partly dominated by extensional and compressional features indicating shallow processes at local scales. © 2010 The Author Geophysical Journal International © 2010 RAS. Source

Bedia Erim F.,Technical University of Istanbul
TrAC - Trends in Analytical Chemistry

Biogenic amines (BAs) are formed in certain food products during storage and processing, causing serious health problems, especially to sensitive persons. This review provides an overview on the studies published between 2011 and 2012, focusing on novelty, improvement, and optimization of analytical methods for the determination of BAs and on their applications to the important groups of food products. © 2013 Elsevier Ltd. Source

Tunca U.,Technical University of Istanbul
Journal of Polymer Science, Part A: Polymer Chemistry

This review highlights the concept of multiple click reaction strategy which is utilized for design and synthesis of well-defined complex macromolecular structures as well as multifunctionalization of well-defined polymers. This review examines the click combinations mainly from double to quadruple and additionally from the most frequently used to the least. The present review may also be regarded as an update for recent reviews dealing with specifically double and triple click reaction combinations in synthetic polymer chemistry. © 2014 Wiley Periodicals, Inc. Source

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