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Article Citation - WoS: 44Citation - Scopus: 49A Neural Network-Based Approach for Calculating Dissolved Oxygen Profiles in Reservoirs(Springer London Ltd, 2003) Soyupak, S; Karaer, F; Gürbüz, H; Kivrak, E; Sentürk, E; Yazici, AA Neural Network (NN) modelling approach has been shown to be successful in calculating pseudo steady state time and space dependent Dissolved Oxygen (DO) concentrations in three separate reservoirs with different characteristics using limited number of input variables. The Levenberg-Marquardt algorithm was adopted during training. Pre-processing before training and post processing after simulation steps were the treatments applied to raw data and predictions respectively. Generalisation was improved and over-fitting problems were eliminated: Early stopping method was applied for improving generalisation. The correlation coefficients between neural network estimates and field measurements were as high as 0.98 for two of the reservoirs with experiments that involve double layer neural network structure with 30 neurons within each hidden layer. A simple one layer neural network structure with 11 neurons has yielded comparable and satisfactorily high correlation coefficients for complete data set, and training, validation and test sets of the third reservoir.Article Citation - WoS: 7Citation - Scopus: 7Trapping Centers and Their Distribution in Tl2ga2< Layered Single Crystals(Pergamon-elsevier Science Ltd, 2009) Isik, M.; Gasanly, N. M.Thermally stimulated current (TSC) measurements with current flowing perpendicular to the layers were carried out on Tl2Ga2Se3S layered single crystals in the temperature range of 10-260K. The experimental data were analyzed by using different methods, such as curve fitting, initial rise and isothermal decay methods. The analysis revealed that there were three trapping centers with activation energies of 12, 76 and 177 meV. It was concluded that retrapping in these centers was negligible, which was confirmed by the good agreement between the experimental results and the theoretical predictions of the model that assumes slow retrapping. The capture cross section and the concentration of the traps have been also determined. An exponential distribution of electron traps was revealed from the analysis of the TSC data obtained at different light illumination temperatures. This experimental technique provided values of 10 and 88 meV/decade for the traps distribution related to two different trapping centers. (C) 2009 Elsevier Ltd. All rights reserved.Article On the Definition of Sequential Consistency(Elsevier Science Bv, 2005) Sezgin, A; Gopalakrishnan, GThe definition of sequential consistency is compared with an intuitive notion of correctness. That the definition is not strong enough is illustrated through a hypothetical memory system which is clearly incorrect, yet sequentially consistent. It is claimed that the reason for this is the absence of a relation between what actually happens (temporal order) and what seems to happen (logical order). A stronger version of sequential consistency is proposed. (c) 2005 Elsevier B.V. All rights reserved.Article Dance of the Corporate Veils: Shareholder Liability in the United States of America and in the Republic of Turkey(2008) Davıs, B. E. Wendy; Hızır, SerdarThe foundation of corporate law is the existence of a legal entity separate from its shareholders, thus shielding shareholders from liability for corporate obligations. Courts have rarely, and with trepidation, pierced through this corporate veil to impose liability on shareholders for corporate malfeasance. These instances have become more common in recent decades, suggesting that corporate investors and parent corporations acquiring subsidiaries need to be diligent to minimize their risk. In this article two academicians discuss the consequences of wrongdoing and mismanagement underlying the pros and cons of the systems adapted by both countries.Conference Object Characterization of Air-Nitrogen Dc Glow Discharge Plasma With Thz Time Domain Spectroscopy(2009) Çinar,K.; Karaoǧlan,G.; Tosun,Z.; Akbar,D.; Altan,H.Transmission of terahertz pulses through DC glow discharge plasma was investigated for different gases. The pressure was kept in between the range of 0.1 torr-0.5 torr and for each pressure different measurements were taken at 5 mA, 10 mA and 15 mA plasma currents. Moreover, emission spectrum of Air, N 2 and Ar plasma analysis were done respectively. It was found that the transmission of terahertz pulses through nitrogen plasma was considerably affected compared to that of the argon plasma. ©2009 IEEE.Article Citation - WoS: 9Citation - Scopus: 9The Approximation of Logarithmic Function by q-bernstein Polynomials in the Case q > 1(Springer, 2007) Ostrovska, SofiyaSince in the case q > 1, q-Bernstein polynomials are not positive linear operators on C[ 0, 1], the study of their approximation properties is essentially more difficult than that for 0 < q < 1. Despite the intensive research conducted in the area lately, the problem of describing the class of functions in C[ 0, 1] uniformly approximated by their q-Bernstein polynomials ( q > 1) remains open. It is known that the approximation occurs for functions admitting an analytic continuation into a disc {z : | z| < R}, R > 1. For functions without such an assumption, no general results on approximation are available. In this paper, it is shown that the function f ( x) = ln( x + a), a > 0, is uniformly approximated by its q-Bernstein polynomials ( q > 1) on the interval [ 0, 1] if and only if a >= 1.Conference Object Citation - Scopus: 1Crm System Implementation in a Multinational Enterprise(2009) Mishra,A.; Mishra,D.The concept of customer relationship management (CRM) resonates with managers in today's competitive economy. As more and more organizations realize the significance of becoming customer-centric in today's competitive era, they embrace CRM as a core business strategy. CRM an integration of information technology and relationship marketing provides the infrastructure that facilitates long-term relationship building with customers at an enterprise-wide level. Successful CRM implementation is a complex, expensive and rarely technical projects. This paper presents the successful implementation of CRM in a multinational organization. This study will facilitate in understanding transition, constraints and implementation of CRM in multinational enterprises. © Springer-Verlag 2009.Article Citation - WoS: 1Citation - Scopus: 1Novel Frequency-Domain Criterion for Elimination of Limit Cycles in a Class of Digital Filters With Single Saturation Nonlinearity(Pergamon-elsevier Science Ltd, 2008) Singh, VimalA frequency-domain criterion for the elimination of limit cycles in a class of digital filters utilizing single saturation nonlinearity is presented. The criterion is derived by exploiting the structural properties of the system under consideration in a greater detail. A novel feature of the criterion is that it takes the form of a matrix inequality, despite the fact that there is single nonlinearity in the system. An example showing the effectiveness of the criterion is given. (c) 2006 Elsevier Ltd. All rights reserved.Article Hopping Conduction in Ga4se3< Layered Single Crystals(Pergamon-elsevier Science Ltd, 2008) Qasrawi, A. F.; Gasanly, N. M.The conduction mechanism in Ga4Se3S single crystals has been investigated by means of dark and illuminated conductivity measurements for the first time. The temperature-dependent electrical conductivity analysis in the region of 100-350 K, revealed the dominance of the thermionic emission and the thermally assisted variable range hopping (VRH) of charged carriers above and below 170 K, respectively. The density of states near the Fermi level and the average hopping distance for this crystal in the dark were found to be 7.20 x 10(15) cm(-3) eV(-1) and 7.56 x 10(-6) cm, respectively. When the sample was illuminated, the Mott's VRH parameters are altered, particularly, the average hopping distance and the density of states near the Fermi level increase when light intensity increases. This action is attributed to the electron generation by photon absorption, which in turn leads to the Fermi level shift and/or trap density reduction by electron-hole recombination. (C) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 1Citation - Scopus: 1Hole-Polar Phonon Interaction Scattering Mobility in Chain Structured Tlse0.75s0.25< Crystals(Wiley-blackwell, 2009) Qasrawi, A. F.; Gasanly, N. M.In this study, the electrical resistivity, charge carriers density and Hall mobility of chain structured TlSe0.75S0.25 crystal have been measured and analyzed to establish the dominant scattering mechanism in crystal. The data analyses have shown that this crystal exhibits an extrinsic p-type conduction. The temperature-dependent dark electrical resistivity analysis reflected the existence of three energy levels located at 280 meV, 68 meV and 48 meV. The temperature dependence of carrier density was analyzed by using the single donor-single acceptor model. The carrier concentration data were best reproduced assuming the existence of an acceptor impurity level being located at 68 meV consistent with that observed from resistivity measurement, The model allowed the determination of the hole effective mass and the acceptor-donor concentration difference as 0.44m(0) and 2.2 x 10(12) cm(-3), respectively. The Hall mobility of the TlSe0.75S0.25 crystal is found to be limited by the scattering of charged carriers over the (chain) boundaries and the scattering of hole-polar phonon interactions above and below 300 K, respectively. The value of the energy barrier height at the chain boundaries was found to be 261 meV. The polar phonon scattering mobility revealed the high-frequency and static dielectric constants of 13.6 and 15.0, respectively. (C) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
