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Article Citation - WoS: 72Citation - Scopus: 75On the Lupas q-analogue of the Bernstein Operator(Rocky Mt Math Consortium, 2006) Ostrovska, SofiyaLet R-n(f,q;x) : C[0, 1] -> C[0, 1] be q-analogues of the Bernstein operators defined by Lupas in 1987. If q = 1, then R-n (f, 1; x) are classical Bernstein polynomials. For q not equal 1, the operators R-n (f, q; x) are rational functions rather than polynomials. The paper deals with convergence properties of the sequence {R-n (f, q; x)}. It is proved that {R-n (f, q(n); x)} converges uniformly to f(x) for any f(x) is an element of C[0, 1] if and only if q(n) -> 1. In the case q > 0, q not equal 1 being fixed the sequence I R. (f, q; x) I converges uniformly to f(x) is an element of C[0, 1] if and only if f(x) is linear.Article Citation - WoS: 20Citation - Scopus: 21Electrochemical Behaviour and Electrochemical Polymerization of Fluoro-Substituted Anilines(Wiley, 2002) Cihaner, A; Önal, AMThe electrochemical behaviour of three fluoro-substituted aniline monomers, 2-fluoroaniline (2FAN), 3-fluoroaniline (3FAN) and 4-fluoroaniline (4FAN), was investigated in aqueous acidic and organic media by means of cyclic voltammetry (CV) studies. Constant potential electrolysis (CPE) of the monomers in acetonitrile-water mixture (1: 1 by volume) using NaClO4 as supporting electrolyte yielded soluble polymers. The mechanism of electrochemical polymerization was investigated using in situ electron spin resonance (ESR) and in situ UV-VIS spectroscopic techniques for one of the monomers (4FAN). Both CV and in situ LTV-VIS measurements indicated that the polymers obtained are in the emeraldine base form. In situ ESR studies indicated that electrochemical polymerization involves a radical-cation as an intermediate. Characterization of polymer products have been carried out using FTIR and NMR spectroscopic techniques, and thermal behaviour was studied using differential scanning calorimetry (DSC). It was found that conductivity can be imparted to assynthesized polyfluoroanilines via iodine doping. (C) 2002 Society of Chemical Industry.Article Citation - WoS: 11Citation - Scopus: 10Cohomology of Sheaves of Frechet Algebras and Spectral Theory(Pleiades Publishing inc, 2005) Dosiev, AAWe propose a holomorpbic functional calculus for a noncommutative operator family generating a supernilpotent Lie subalgebra. This calculus extends Taylor's holomorphic functional calculus.Conference Object Citation - WoS: 5Citation - Scopus: 3Evaluation of Efficiencies of Diffuse Allochthonous and Autochthonous Nutrient Input Control in Restoration of a Highly Eutrophic Lake(I W A Publishing, 2002) Muhammetoglu, A; Muhammetoglu, H; Soyupak, SMogan Lake is an important recreational area for Metropolitan Ankara-Turkey. It is a shallow eutrophic lake with a dense growth of macrophytes. The main contributors of nutrients and other pollutants to the lake are the creeks carrying the runoff water from the watershed and upland farming land, in addition to the domestic and industrial wastewater discharges from a nearby town and industries. Hydrodynamic and water quality modeling techniques were used to determine the optimum management schemes for the lake restoration and diffuse pollution control. Management scenarios were devised and tested to control allochthonous and autochthonous nutrient inputs to the lake. Phosphorus and nitrogen load reductions were the main test elements for the control of allochthonous nutrient inputs. The scenario analysis revealed that reduction of phosphorus and nitrogen loads from diffused sources will have a marginal effect on controlling eutrophication if macrophyte growth is left uncontrolled. Scenarios employing macrophyte harvesting and sediment dredging have been evaluated for autochthonous nutrient input control. Sediment dredging alone has been shown to yield the most favorable conditions for water quality improvement in Mogan Lake. Further, control of diffuse pollution was an essential final step to achieve an acceptable long-term sustainable water quality improvement in the lake.Article Citation - WoS: 5Citation - Scopus: 6Material Flow Control in High Pressure Sheet Metal Forming of Large Area Parts With Complex Geometry Details(verlag Stahleisen Mbh, 2005) Trompeter, M; Önder, E; Homberg, W; Tekkaya, E; Kleiner, MWorking media based forming processes show advantages compared to the conventional deep drawing in the range of sheet metal parts with complex geometry details. By High Pressure Sheet Metal Forming (HBU), complex parts can be formed with reduced tool costs, fewer process steps, and improved part properties, particularly by the use of high strength steels. In order to use these advantages to full capacity, the material flow into the area of the geometry details needs to be optimised. The key element for the material flow control is a multi-point blank holder. In combination with flange draw-in sensors, a closed loop flange draw-in control can be built up which guarantees a reproducible material flow and, consequently, defined part properties. Furthermore, a favourable pre-distribution of sheet metal material can be reached which leads to a widening of the process limits. Considering a large area sheet metal part with a complex door handle element as example, strategies for the material flow control will be discussed in this paper. The conclusions are based on FE-simulations as well as experimental findings.Article Citation - WoS: 96Citation - Scopus: 100Effect of Progesterone on Dppc Membrane: Evidence for Lateral Phase Separation and Inverse Action in Lipid Dynamics(Elsevier Science inc, 2005) Korkmaz, F; Severcan, FInteractions of progesterone with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) triultilamellar liposomes were investigated as a function of temperature and progesterone concentration by using three non-invasive techniques namely Fourier transform infrared spectroscopy, turbidity at 440 nm, and differential scanning calorimetry. The results reveal that progesterone changes the physical properties of DPPC bilayers by decreasing the main phase-transition temperature, abolishing the pre-transition, broadening the phase-transition profile, disordering the system both in gel and liquid crystalline phase, increasing the dynamics at low concentrations whereas stabilizing the membrane at high concentrations, and inducing phase separation. Progesterone does not change the hydration of the C=O groups, while it strengthens the hydrogen bonding between the PO (2) over bar groups of lipids and the water molecules around. (c) 2005 Elsevier Inc. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 5Concentration Dependent Different Action of Progesterone on the Order, Dynamics and Hydration States of the Head Group of Dipalmitoyl-Phosphatidylcholine Membrane(Hindawi Ltd, 2005) Korkmaz, F; Kirbiyik, H; Severcan, FInteractions of progesterone with zwitterionic dipalmitoyl phosphatidylcholine (DPPC) multilamellar liposomes (MLVs) were investigated as a function of progesterone concentration at selected temperatures monitoring both the gel and liquid crystalline phase, by using Fourier Transform Infrared spectroscopy (FTIR). It has been show that the effect of progesterone on membrane dynamics is dependent on progesterone concentration. At 1 mol%, which is close to physiological level, progesterone behaves differently. At this concentration the decrease in dynamics is more noticeable. Additionally a dramatic decrease in the strength of hydrogen bonding in the interfacial region of the bilayer is also observed. When concentration increases up to 12 mol% opposite behaviour is observed at all interactions. Above 12 mol%, progesterone-DPPC interactions shows almost linear plot.Conference Object Citation - WoS: 1On Euler's differential methods for continued fractions(Kent State University, 2006) Khrushchev, Sergey; MathematicsA differential method discovered by Euler is justified and applied to give simple proofs to formulas relating important continued fractions with Laplace transforms. They include Stieltjes formulas and some Ramanujan formulas. A representation for the remainder of Leibniz's series as a continued fraction is given. We also recover the original Euler's proof for the continued fraction of hyperbolic cotangent.Article Citation - WoS: 107Citation - Scopus: 141Flexibility Based Approach for Damage Characterization: Benchmark Application(Asce-amer Soc Civil Engineers, 2004) Bernal, D; Gunes, BA flexibility based damage characterization technique is described and its performance is examined in the context of Phase 1 of the benchmark study developed by the IASC-ASCE SHM Task Group. Noteworthy features of the analytical development are: (1) the methodology used to extract a matrix that is proportional to the flexibility when the excitation is stochastic; (2) the technique used to interrogate the changes in flexibility (or flexibility proportional matrices) with regards to the location of the damage; and (3) the method used to quantify the damage without the use of a model. The strategy proved successful in all the cases considered.Article Citation - WoS: 18Citation - Scopus: 18Growth, Electrical and Structural Characterization of Β-Gase Thin Films(Springer, 2003) Parlak, M; Qasrawi, AF; Erçelebi, ÇGaSe thin films were deposited onto the glass substrates kept at 200degrees and 300degreesC by the thermal evaporation of GaSe crystals under the pressure of 10(-5) Torr. X-ray analysis of the films revealed that films grown at 200. C are amorphous in nature while the films grown at 300degreesC are polycrystalline beta-GaSe. The temperature dependent electrical conductivity measurements in the region of 320-100 K for the films grown at 300degreesC showed that the transport mechanisms are the thermionic emission of charged carriers and the variable range hopping above and below 180 K, respectively. Space charge limited current (SCLC) studies have also been performed on these films through the current-voltage measurements at different temperatures and a dominant hole trap at 0.233 eV from the top of the valance band with a trap density of similar to1.6 x 10(11) cm(-3) is identified. (C) 2003 Kluwer Academic Publishers.
