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Istanbul, Turkey

Istanbul Şehir University is a private, non-profit university located in Istanbul, Turkey. It was established in 2008 by the Bilim ve Sanat Vakfı , a foundation for science and arts. The university started its education in the academic year of 2010-11 at its campus in Altunizade, Istanbul following a ceremony held on October 5, 2010 that was also attended by State president Abdullah Gül, Prime minister Recep Tayyip Erdoğan and Minister of Foreign Affairs Ahmet Davutoğlu. Wikipedia.

Onat N.C.,University of Central Florida | Kucukvar M.,Istanbul Sehir University | Tatari O.,University of Central Florida
Applied Energy | Year: 2015

Electric vehicles (EVs), plug-in hybrid electric vehicles (PHEVs), and hybrid electric vehicles (HEVs) are often considered as better options in terms of greenhouse gas emissions and energy consumption compared to internal combustion vehicles. However, making any decision among these vehicle options is not a straightforward process due to temporal and spatial variations, such as the sources of the electricity used and regional driving patterns. In this study, we compared these vehicle options across 50 states, taking into account state-specific average and marginal electricity generation mixes, regional driving patterns, and vehicle and battery manufacturing impacts. Furthermore, a policy scenario proposing the widespread use of solar energy to charge EVs and PHEVs is evaluated. Based on the average electricity generation mix scenario, EVs are found to be least carbon-intensive vehicle option in 24 states, while HEVs are found to be the most energy-efficient option in 45 states. In the marginal electricity mix scenario, widespread adoption of EVs is found to be an unwise strategy given the existing and near-future marginal electricity generation mix. On the other hand, EVs can be superior to other alternatives in terms of energy-consumption, if the required energy to generate 1. kW. h of electricity is below 1.25. kW. h. © 2015 Elsevier Ltd. Source

Yigitcanlar T.,Queensland University of Technology | Bulu M.,Istanbul Sehir University
Environment and Planning A | Year: 2015

Knowledge-based urban development (KBUD) has become a popular pursuit for cities, especially from the developing countries, to fast track the catching up process with their counterparts in developed nations. Nevertheless, for these cities the KBUD progress is daunting and full of challenges. The authors aim to shed light on the major KBUD challenges of emerging local economies by undertaking an in-depth empirical investigation in one such city. They scrutinize the prospects and constraints of Istanbul in her KBUD journey through comparative performance and policy context analyses. The findings reveal invaluable insights, not only for Istanbul to reshape the policy context and align development with contemporary KBUD better, but also for other emerging local economies to learn from these experiences. © 2015 Pion Limited. All rights reserved. Source

Tunaboylu B.,Istanbul Sehir University
IEEE Transactions on Device and Materials Reliability | Year: 2014

Novel spring contactors were designed and characterized for wafer-level interposer and high-speed package test system applications, especially for wafer-level packages. These contactors can be used as replacement for vertical wafer probes as well as test sockets used in the final test. The contactor pin consists of a plunger section made of beryllium copper and a plated helical stainless steel spring wire. It is 5 mm in uncompressed total length, including the plunger and the spring. The overall diameter of the spring wire section was 0.51 mm. The design of the contactor is much simpler and more scalable than that of traditional spring pins called Pogo pins used in package tests. A test socket containing 36 contactor pins was constructed for tests and measurements. The experimental characterization shows $-$1-dB bandwidth of 3.73 GHz for 0.8-mm pitch, measured by the direct contact method. This experimental result correlates well with the simulated results. The rise time was 82 ps as measured by TDR, and the propagation delay was 23 ps. The electrical conduction path is through the pin and the spring, making it a reliable contact. However, the electrical path is known to be through the barrel, not the spring for the regular spring pins. © 2001-2011 IEEE. Source

Tekiner-Mogulkoc H.,Istanbul Sehir University | Coit D.W.,Rutgers University
IEEE Transactions on Reliability | Year: 2011

System reliability optimization models considering uncertainty are described, and new algorithms are proposed to minimize the coefficient of variation of the system reliability estimate. This is a realistic, important formulation because the reliability of most components is not known with certainty, and decision-makers are often risk averse, preferring a system with a slightly lower estimated reliability if it is a more certain measure. The redundancy allocation problem can be defined as the selection of the system configuration and the type of the components to optimize some objective function(s) while satisfying some system related constraints. In this paper, we propose algorithms to minimize the coefficient of variation of the system reliability estimate with respect to a minimum system reliability constraint, and some other system related constraints. Two algorithms are presented. For problems where component mixing is not allowed, an optimal algorithm is presented based on linear integer programming. For problems where mixing is allowed, a heuristic approach is presented based on a combined neighborhood search, and a linear integer programming approach. The heuristic starts with the solution of those problems where mixing components is not allowed, and searches the neighborhood of this solution to find better prospective solutions for the problems where mixing components is allowed. Then, a linear integer programming problem is solved to identify the recommended solution to the problem. © 2006 IEEE. Source

Tunaboylu B.,Istanbul Sehir University
Materials Letters | Year: 2012

A method was developed for the deposition and annealing of Ni-alloy layers to obtain a low-stress film required for high cycle wafer probe applications. Ni-alloy layers with uniform compositions from 0.145 to 0.357 wt.% of Mn were electrodeposited. A high strength alloy with good ductility was produced using pulsed plating with a low internal stress level of 14 MPa. In addition, a method was developed to produce a modulated composition of Mn in Ni layers from a single bath to further improve the mechanical properties of the deposits. Multilayer NiMn layers with a composition of 0.4, 0.1, and 0.6 wt.% of Mn were produced. The microstructures showed mostly microcrystalline grains with shear band structures and finer grains with a lamellar structure were observed for higher Mn contents. © 2011 Elsevier B.V. All rights reserved. Source

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