Istanbul, Turkey
Istanbul, Turkey

Okan University is a private university in Istanbul, Turkey. Wikipedia.


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Grant
Agency: Cordis | Branch: H2020 | Program: IA | Phase: GV-6-2015 | Award Amount: 5.39M | Year: 2016

The automotive industry has made a substantial effort in recent years in developing powertrain technologies to improve fuel efficiency on Heavy-Duty Vehicles (HDVs). Due to increasing road freight traffic, however, projections indicate that total HDV energy use and CO2 emissions are expected to remain stable at the current level over the long term, if no policy action is taken. This is clearly incompatible with the goal of reducing greenhouse gas emissions from transport by around 60% below 1990 levels by 2050. The overall objective of optiTruck is to further improve energy efficiency by at least 20% on Euro VI HDVs (40t). To achieve this, optiTruck will develop a global optimiser which brings together the most advanced technologies from powertrain control and intelligent transport systems, with a number of innovative and complementary elements to maximise the potential utilisation of individual innovations. Through real driving trials, optiTruck will demonstrate this objective, taking account road topography, traffic and weather condition, vehicle configuration and transport mission. optiTruck will develop a comprehensive impact assessment methodology to extend this local and small-scale demonstration to a wider evaluation to explore potential benefits of using the rich cloud data sources and powerful computing facilities for fast-than-real-time modelling and simulation. It will also take account of social equity, economic, and environmental factors in the assessment to address the main societal challenges for the sector. optiTruck will facilitate the creation of a global platform not only for exchanging existing knowledge between automotive industries, but also for promoting horizontal collaboration in new ways essential for wider uptake of energy saving solutions across the sector, Europe and the world, which is the ultimate goal the optiTruck partners strive to achieve within and beyond this project.


Grant
Agency: Cordis | Branch: FP7 | Program: BSG-SME | Phase: SME-1 | Award Amount: 1.47M | Year: 2008

The 24-month ELEVATE project proposes a hybrid training and certification environment, which integrates the application software to be taught in the pedagogical-documented educational process, allowing the software development SMEs to deliver innovative e-training services and to address (more than adequately) the needs of their business partners and customers. Thus, the ELEVATE project addresses the business needs of the software development SMEs participating in the project in the field of application software training through their business partners and customers networks. As the software development SMEs have restricted resources to allocate in research and development (R&D) activities with regard to secondary corporate objectives, including e-training in the produced application software products, the proposed ELEVATE project provides participating SMEs with potentials and financial support to outsource a critical mass of research and technological development (RTD) activities to industrial companies and universities with larger research capacity and proved, successful experience in R&D, European-wide initiatives. The ELEVATE RTD performers will undertake significant research activities on behalf of the participating SMEs and deliver technology know-how in the fields of e-learning, educational content aggregation and material creation, learning management system and application software integration, and pedagogic standards and models. Led by CAS Software AG, the consortium consists of 8 partners from 7 EC member and associated countries (Germany, Belgium, Swiss, Greece, Cyprus, Italy and Turkey), including software development SMEs, industrial companies and universities.


Aptoula E.,Okan University
IEEE Transactions on Geoscience and Remote Sensing | Year: 2014

In this paper, we present the results of applying global morphological texture descriptors to the problem of content-based remote sensing image retrieval. Specifically, we explore the potential of recently developed multiscale texture descriptors, namely, the circular covariance histogram and the rotation-invariant point triplets. Moreover, we introduce a couple of new descriptors, exploiting the Fourier power spectrum of the quasi-flat-zone-based scale space of their input. The descriptors are evaluated with the UC Merced Land Use-Land Cover data set, which has been only recently made public. The proposed approach is shown to outperform the best known retrieval scores, despite its shorter feature vector length, thus asserting the practical interest of global content descriptors as well as of mathematical morphology in this context. © 1980-2012 IEEE.


Ozturk S.B.,Okan University | Toliyat H.A.,Texas A&M University
IEEE/ASME Transactions on Mechatronics | Year: 2011

In this paper, the position-sensorless direct torque and indirect flux control of brushless dc (BLDC) motor with nonsinusoidal back electromotive force (EMF) has been extensively investigated. In the literature, several methods have been proposed for BLDC motor drives to obtain optimum current and torque control with minimum torque pulsations. Most methods are complicated and do not consider the stator flux linkage control, therefore, possible high-speed operations are not feasible. In this study, a novel and simple approach to achieve a low-frequency torque ripple-free direct torque control (DTC) with maximum efficiency based on dq reference frame is presented. The proposed sensorless method closely resembles the conventional DTC scheme used for sinusoidal ac motors such that it controls the torque directly and stator flux amplitude indirectly using d-axis current. This method does not require pulsewidth modulation and proportional plus integral regulators and also permits the regulation of varying signals. Furthermore, to eliminate the low-frequency torque oscillations, two actual and easily available line-to-line back EMF constants (kba and kca) according to electrical rotor position are obtained offline and converted to the dq frame equivalents using the new line-to-line park transformation. Then, they are set up in the look-up table for torque estimation. The validity and practical applications of the proposed sensorless three-phase conduction DTC of BLDC motor drive scheme are verified through simulations and experimental results. © 2010 IEEE.


Aptoula E.,Okan University
Journal of Visual Communication and Image Representation | Year: 2012

The two principal morphological texture descriptors, granulometry and morphological covariance, rely on the common principle of successive filtering of an image using a variety of structuring elements, from which feature vectors are subsequently computed. A crucial stage of their computation is the numerical characterization or parameterization of each of the filtered images. In this regard, the zero-th statistical moment is the traditional measure, while the use of higher order moments has also been reported. In this paper, we present the results of a comparative study, concentrating on the potential of various statistical moments for the task of parameterization, while additionally investigating the contribution of Fourier transform moments. The experiments are conducted with focus on texture description effectiveness and on noise robustness, using publicly available texture collections: Outex, CUReT and KTH-TIPS2b, where it is shown that the combination of moments leads to superior classification performance even at high noise levels. © 2012 Elsevier Inc. All rights reserved.


Based on the principal proofs we have provided in a previous article, herein we draw a unique quantum mechanical architecture, matter is made of. We call it "universal matter architecture" (UMA). It is this architecture that principally works as the internal machinery of the end results of the special theory of relativity, were the object brought to a uniform translational motion, or that of the end results of the general theory of relativity, were the object at hand embedded in a gravitational field, in effect, any field the object can interact with. Herein effort is devoted particularly to disclose UMA, chiefly on the basis of the structure of diatomic molecules, which well yields an unequal systematization of these molecules, in fact, also that of polyatomic molecules. We show how UMA provides with the opportunity of resuming the mysterious retardation of the bound muon decay rate. It is further amazing that a gas made of billion times billion times billion molecules is also structured in accordance with the matter architecture we disclose. © 2014 Physics Essays Publication.


Ozer A.T.,Okan University
Geosynthetics International | Year: 2016

The use of expanded polystyrene geofoam (geofoam block) has been gaining momentum in roadway expansion projects. They are traditionally placed along the slope face of the existing roadway embankment as a side-hill fill. However, previous studies have shown the detrimental effects of seepage forces on the side-hill fill type of geofoam block configurations. In order to improve the performance of traditional embankment-widening configuration under seepage forces, an alternative geofoam block assembly is proposed. For this purpose, a lysimeter with dimensions of 60 cm high, 20 cm wide, and 200 cm long was constructed in the laboratory. Awater reservoir located at the end of the lysimeter provided three different constant pressure heads (25 cm-, 38 cm-, and 50 cm-H2O pressure) during the tests. An embankment-widening geofoam block assembly was placed along the slope face of marginally stable sandy embankment to investigate the effects of seepage on the stability of geofoam block assembly. The dimensions of the geofoam blocks used to construct the embankment-widening sections were 2.5 cm high, 5 cm wide, and 15 cm long. In addition to the laboratory physical testing, factors of safety against global stability and hydrostatic sliding failures were studied through coupled numerical modelling. Stability modelling comprised fully coupled variably saturated flow and conventional limit equilibrium analysis to quantify the performance of the lysimeter test against global stability failure. Factor of safety against hydrostatic sliding was quantified using fully coupled variably saturated flow and stress-deformation modelling. Both laboratory and numerical models showed that the proposed geofoam block configuration significantly improved the performance of traditional side-hill fill embankment-widening technique under seepage forces. © 2015 Thomas Telford Ltd.


Dundar S.,Okan University | Sahin T.,Yildiz Technical University
Transportation Research Part C: Emerging Technologies | Year: 2013

Train re-scheduling problems are popular among researchers who have interest in the railway planning and operations fields. Deviations from normal operation may cause inter-train conflicts which have to be detected and timely resolved. Except for very few applications, these tasks are usually performed by train dispatchers. Due to the complexity of re-scheduling problems, dispatchers utilize some simplifying rules to resolve conflicts and implement their decisions accordingly. From the system effectiveness and efficiency point of view, their decisions should be supported with appropriate tools because their immediate decisions may cause considerable train delays in future interferences. Such a decision support tool should be able to predict overall implications of the alternative solutions. Genetic algorithms (GAs) for conflict resolutions were developed and evaluated against the dispatchers' and the exact solutions. The comparison measures are the computation time and total (weighted) delay due to conflict resolutions. For benchmarking purposes, artificial neural networks (ANNs) were developed to mimic the decision behavior of train dispatchers so as to reproduce their conflict resolutions. The ANN was trained and tested with data extracted from conflict resolutions in actual train operations in Turkish State Railways. The GA developed was able to find the optimal solutions for small sized problems in short times, and to reduce total delay times by around half in comparison to the ANN (i.e., train dispatchers). © 2012 Elsevier Ltd.


An arbitrary increase of rest masses input to the quantum mechanical description of an atomic or molecular object leads to the increase of the related total energy (i.e., the eigenvalue), and contraction of the size, associated with it. Furthermore, this occurrence, on the basis of the quantum mechanical description in consideration, yields the "invariance" of the quantity [total energy×mass×size2], framing a fundamental architecture, matter is made of. Henceforth, we will call this latter quantity "quantum-mechanical-description-scaling-invariance," or briefly quantummechanical-description-scaling-invariance (QMDSI). This leads, amongst other things, to a whole new systematic of diatomic molecules, in general polyatomic molecules. On the other hand, one can check that the quantity [total energy×mass×size2] happens to be a Lorentz invariant quantity, for one thing; dimensionally, it comes to the square of the action quantity or the square of Planck Constant (which is well Lorentz invariant). Thus, it appears that the QMDSI we disclose about [total energy×mass×size2] with regards to a hypothetical mass change in a quantum mechanical description, happens to work as the inherent mechanism of the end results of the Special Theory of Relativity, was the object in consideration, brought to a uniform translational motion. Or similarly, it comes to work as the innate machinery of the end results of the General Theory of Relativity, where this object is embedded in a gravitational field. In both cases, it is question of a "real, overall mass change," which in return can well be considered, as an input to the quantum mechanical description, in consideration, to investigate the related results. One can further show that the occurrence we unveil holds not only for a gravitational field but generally for all fields the object at hand interacts with. Note that, herein, we propose to use the word "field," in the sense of "effective surrounding." Indeed, in our approach, the related changes take place in the respective cores of the interacting bodies, and not, in a rather fuzzy way, in their environment. Next to the rest masses, there remains one other parameter one can alter in the given quantum mechanical description, of mainly (but without any loss of generality, really), atomistic and molecular objects: It is the product of electric charges, coming into play. Its arbitrary change, in fact, fully reflects the actual Lorentz transformation of electric forces, where the object is brought to a uniform translational motion. Herein, we provide principal mathematical proofs. In a subsequent article, we will disclose the related architecture, matter is made of. © 2013 Physics Essays Publication.


Cifter A.,Okan University
Physica A: Statistical Mechanics and its Applications | Year: 2011

This paper introduces wavelet-based extreme value theory (EVT) for univariate value-at-risk estimation. Wavelets and EVT are combined for volatility forecasting to estimate a hybrid model. In the first stage, wavelets are used as a threshold in generalized Pareto distribution, and in the second stage, EVT is applied with a wavelet-based threshold. This new model is applied to two major emerging stock markets: the Istanbul Stock Exchange (ISE) and the Budapest Stock Exchange (BUX). The relative performance of wavelet-based EVT is benchmarked against the Riskmetrics-EWMA, ARMAGARCH, generalized Pareto distribution, and conditional generalized Pareto distribution models. The empirical results show that the wavelet-based extreme value theory increases predictive performance of financial forecasting according to number of violations and tail-loss tests. The superior forecasting performance of the wavelet-based EVT model is also consistent with Basel II requirements, and this new model can be used by financial institutions as well. © 2011 Elsevier B.V. All rights reserved.

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