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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.Article Citation - WoS: 5Citation - Scopus: 6Synthesis, X-Ray Data, and Hall Effect Measurements of Li-Doped Tl-Ba Superconductor(Wiley-v C H verlag Gmbh, 2003) Kayed, TSLithium-doped Tl-based superconductor was prepared by adding an amount of 0.3 mol.% to the Tl1.8Ba2Ca2.2Cu3Ox compound. The usual solid-state reaction method has been applied under optimum conditions. The x-ray data of the sample show a tetragonal structure with a high ratio of Tl-2223 superconducting phase. The sample showed a transition at 125 K and the zero resistance was observed at 117 K. Longitudinal (transport) and transverse (Hall) resistivities were measured at different temperatures under different magnetic fields and the data were interpreted. A positive Hall coefficient was observed at normal state and a sign reversal appears at temperatures lower than the critical temperature. (C) 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.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.Conference Object Citation - WoS: 1A Cognitive Evaluation for Meetings in Software Development Process(Springer-verlag Berlin, 2009) Misra, Sanjay; Akman, IbrahimSoftware development; includes number of different type of meetings in the whole development process. The cognitive activities also play an important role in decision making activities in these meetings since they are carried out, by human being. In this paper, we evaluated the relevance of meetings in different phases of the software development process with reference to cognitive aspects.Article Citation - WoS: 1Electrochemistry of Acetate-, Carbonate-, Sulfate-, and Dihydrogenphosphate-Bridged Dirhodium(ii) Complexes(verlag Z Naturforsch, 2003) Yaman, SO; Önal, AM; Isci, HComplexes, [Rh-2(B-B)(4)L-2](n) (B-B = CH3CO2-, L = CH3CN, H2O, Cl-, Br-, SCN-; B-B CO32-, SO42-, H2PO4-, L = H2O, Cl-, Br-, SCN-) were prepared and their cyclic voltammograms (CV) and electronic absorption spectra were measured in solution. The CV of the complexes exhibits a reversible one-electron transfer from a metal-based orbital. Constant potential electrolysis at the oxidation peak potential of [Rh-2(O2CCH3)(4)(NCCH3)(2)] in acetonitrile yielded [Rh-2(O2CCH3)(4)(NCCH3)(2)](+), a mixed valent Rh(II)-Rh(III) cation complex. The formation of the mixed valent complex was monitored by measuring electronic absorption spectra of the solution in situ during the oxidative electrolysis. The reductive electrolysis of the mixed valent complex solution, in the same electrolysis cell, yielded the original electronic absorption spectrum of the starting complex. The changes in the oxidation and reduction potentials of the complexes with different axial ligands, L = H2O, Cl-, Br-, SCN-, are correlated to the relative energy changes of HOMO and LUMO of the complexes, which indicates the metal-axial ligand sigma- and pi-bonding interactions. Spectroscopic and CV data indicate that the degree of a-interaction is Cl- > Br- > SCN-, and that of pi-interaction is Br- > SCN- > Cl-.Article Citation - WoS: 7Citation - Scopus: 12A FUZZY CONCEPTUAL MODEL FOR MULTIMEDIA DATA WITH A TEXT-BASED AUTOMATIC ANNOTATION SCHEME(World Scientific Publ Co Pte Ltd, 2009) Kucuk, Dilek; Burcuozgur, N.; Yazici, Adnan; Koyuncu, MuratThe size of multimedia data is increasing fast due to the abundance of multimedia applications. Modeling the semantics of the data effectively is crucial for proper management of it. In this paper, we present a fuzzy conceptual data model for multimedia data which is also generic in the sense that it can be adapted to all multimedia domains. The model takes an object-oriented approach and it handles fuzziness at different representation levels where fuzziness is inherent in multimedia applications and should be properly modeled. The proposed model also has the nice feature of representing the structural hierarchy of multimedia data as well as the spatial and temporal relations of the data. The model is applied to the news video domain and implemented as a fuzzy multimedia database system where it turns out to be effective in representing the domain and thereby provides an evidence for the general applicability of the model. The model is accompanied by an automatic multimedia annotation scheme which makes use of information extraction techniques on the corresponding multimedia texts.Article Citation - WoS: 4Citation - Scopus: 4Uncorrelatedness sets for random variables with given distributions(Amer Mathematical Soc, 2005) Ostrovska, SLet xi(1) and xi(2) be random variables having finite moments of all orders. The set U(xi(1),xi(2)) := {( j, l) is an element of N-2 : E(xi(1)(j)xi(2)(l)) = E(xi(1)(j)) E(xi(2)(l))} is said to be an uncorrelatedness set of xi(1) and xi(2). It is known that in general, an uncorrelatedness set can be arbitrary. Simple examples show that this is not true for random variables with given distributions. In this paper we present a wide class of probability distributions such that there exist random variables with given distributions from the class having a prescribed uncorrelatedness set. Besides, we discuss the sharpness of the obtained result.Conference Object Citation - WoS: 13Citation - Scopus: 34Swarm Aggregations Using Artificial Potentials and Sliding Mode Control(Ieee, 2003) Gazi, VIn this article we build on our earlier results in [1, 2] on swarm stability. In [1, 2] we had considered aggregating swarm model in n-dimensional space based on artificial potential functions for inter-individual interactions and motion along the negative gradient of the combined potential. Here we consider a general model for vehicle dynamics of each agent (swarm member) and use sliding mode control theory to force their motion to obey the dynamics of the swarm considered in [1, 2]. In this context, the results in [1, 2] serve as a "proof of concept" for swarm aggregation, whereas the present results serve as possible implementation method for engineering swarms with given vehicle dynamics. Moreover, the presented control scheme is robust with respect to disturbances and system uncertainties.Article Isı Etkisi Altındaki Fonksiyonel Derecelendirilmiş Malzemeden Yapılmış Uzun Tüplerde Plastik Akmanın Başlaması(2006) Akış, Tolgaİçerisinde düzgün olmayan ısı üreten, fonksiyonel derecelendirilmiş malzemeden yapılmış uzun bir tüpün elastik davranışı analitik olarak incelenmiştir. Tüpün ısı iletim katsayısının ve elastisite modülünün radyal koordinat boyunca lineer olmayan formda değiştikleri varsayılmıştır. Tresca akma kriteri kullanılarak, fonksiyonel derecelendirme parametrelerinin tüpteki plastik akmanın başlangıcına etkileri incelenmiş, akmanın bu parametrelere bağlı olarak önce iç yüzeyden, önce dış yüzeyden, ya da tüpün iç bölgesinden başlayabileceği gözlenmiştir.Article Citation - Scopus: 8Computation of a Tunable Slot-Loaded Equilateral Triangular Microstrip Antenna(2009) Aydın,E.In this paper, a simple closed form expression is developed to accurately estimate the lower and upper operating frequencies of a single feed slot loaded triangular patch (SLTP) with variations of the bent slot lengths. It is obtained by using cavity model analysis and useful to antenna engineers for accurately predicting both operating resonant frequencies of the SLTP. The theory is compared with the experimental results available in the literature, and excellent agreement is observed. The proposed computation is also extended to the analysis of tunability of the SLTP as a function of the air-gap height. © Journal of electromagnetic waves and applications. All Rights reserved.
