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Article Citation - WoS: 10Citation - Scopus: 9Cohomology 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: 42Citation - Scopus: 47Modified Form of Liu-michel's Criterion for Global Asymptotic Stability of Fixed-Point State-Space Digital Filters Using Saturation Arithmetic(Ieee-inst Electrical Electronics Engineers inc, 2006) Singh, VimalA criterion for the global asymptotic stability of fixed-point state-space digital filters using saturation arithmetic was previously given by Liu and Michel. A modified form of their criterion is presented.Article Citation - WoS: 5Citation - Scopus: 6Photoelectronic and Electrical Properties of Tl2ingas4< Layered Crystals(Pergamon-elsevier Science Ltd, 2007) Qasrawi, A. F.; Gasanly, N. M.Tl2InGaS4 layered crystals are studied through the dark electrical conductivity, space charge limited current and illumination- and temperature-dependent photoconductivity measurements in the temperature regions of 220-350 K, 300-400 K and 200-350 K, respectively. The space charge limited current measurements revealed the existence of a single discrete trapping level located at 0.44 eV. The dark electrical conductivity showed the existence of two energy levels of 0.32 eV and 0.60 eV being dominant above and below 300 K, respectively. The photoconductivity measurements reflected the existence of two other energy levels located at 0.28 eV and 0.19 eV at high and low temperatures, respectively. The photocurrent is observed to increase with increasing temperature up to a maximum temperature of 330 K. The illumination dependence of photoconductivity is found to exhibit supralinear recombination in all the studied temperature ranges. The change in recombination mechanism is attributed to exchange in the behavior of sensitizing and recombination centers. (C) 2006 Elsevier Ltd. All rights reserved.Article Citation - WoS: 44Citation - Scopus: 45A Novel Electrochromic and Fluorescent Polythienylpyrrole Bearing 1,1′-Bipyrrole(Pergamon-elsevier Science Ltd, 2009) Cihaner, Atilla; Mert, Olcay; Demir, Ayhan S.A novel conducting polymer was successfully synthesized via electropolymerization of 1-(1H-pyrrol-1-yl)-2,5-di(thiophen-2-yl)-1H-pyrrole. The electrochemical and electro-optical properties of the corresponding polymer, which was the first example of polymer containing 1,1'-bipyrrole units, were elaborated using electroanalytical and spectroscopic techniques. Cyclic voltammograms and electro-optical studies showed that the polymer has a stable and well-defined reversible redox process as well as electrochromic behavior. The processable polymer film also possessed a yellowish orange light emitter property. (C) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 20Citation - Scopus: 26Simplified software inspection process in compliance with international standards(Elsevier Science Bv, 2009) Mishra, Deepti; Mishra, AlokA significant amount of software is developed all over the world by small and medium size software organizations. These organizations do not have enough infrastructures and resources to implement an austere quality plan. Software inspection is a fundamental component of the software quality assurance process. Formal review methods are rigorous and their implementation is cumbersome for small and medium enterprises. In this paper, we have presented a new simplified inspection process which is easy to implement. requires fewer resource and almost no documentation. Also, people who are conducting this inspection need not be present at the same place during most stages of the inspection process. We have also compared this process with IEEE and NASA standards for software inspection and found that it meets almost 99% of both standards. While there has been much research on inspection, little attention is paid towards compliance with international standards. These results could be used as a basis for further research in software inspection and process towards aligning with international standards. This process has been successfully implemented in a CMM level 3 software development organization which is striving to accomplish higher maturity levels to establish at the international level. (C) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 7Citation - Scopus: 10Efficient Software Review Process for Small and Medium Enterprises(inst Engineering Technology-iet, 2007) Mishra, D.; Mishra, A.A considerable amount of software is produced world-wide by small and medium enterprises (SMEs). These organisations do not have enough resources to implement a rigorous quality plan. It has been established that reviews of various artifacts play a very important role in ensuring the quality of software. Traditional review methods are rigorous and their implementation is cumbersome for SMEs. A new review process which is easy to implement and requires almost no documentation is introduced. It is based on reviewers' efforts to produce high-quality software while minimising the inspection cost. Additionally, people who are conducting this review need not be present at the same place during most phases of the review process. This process has been successfully implemented in a CMM level 3 software development company intending to achieve CMMI level 5 and results are found to be quite encouraging.Article Citation - WoS: 94Citation - Scopus: 95A New Conducting Polymer Bearing 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (bodipy) Subunit: Synthesis and Characterization(Pergamon-elsevier Science Ltd, 2008) Cihaner, Atilla; Algi, FatihA new monomer system based on thiophene, pyrrole and 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene dye (SNS-BODIPY) was synthesized and its corresponding polymer (PSNS-BODIPY) was obtained via repetitive cycling or constant potential electrolysis in 0.1 M tetrabutylammonium hexafluorophosphate dissolved in dichloromethane. The PSNS-BODIPY film has very stable and well-defined reversible redox couples during p-doping process. Multi-electrochromic polymer film has a band gap of 2.9 eV with two absorption bands in its neutral state at 351 and 525 nm, attributed to the polymer backbone and BODIPY subunits, respectively. The percentage transmittance changes between both states (neutral and oxidized) were found as 12.1% for 351 nm and 17.7% for 525 nm in the visible region as well as 46.2% for 1050 nm in the near-infrared region. Beyond the robustness, the PSNS-BODIPY film has high redox stability (retaining 53.3% of its electroactivity at 351 nm after 2000 switching) with a low response time of 1.0 s. (C) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 102Citation - Scopus: 113A 1.6-Mm, Metal Tube Ultrasonic Motor(Ieee-inst Electrical Electronics Engineers inc, 2003) Cagatay, S; Koc, B; Uchino, KA miniaturized metal tube ultrasonic motor, the dimensions of which are 1.6 mm in diameter and 6 rum in length, was developed. Two flattened surfaces with 90-degrees were ground on the outer surface of the stator. Two PZT-based piezoelectric ceramics were bonded onto these flat surfaces. The asymmetrical surface of the stator developed the split of the two degenerated orthogonal bending modes, resulting in a wobble motion. The working frequency of the 1.6-mm motor with 6 mm in length was 130 kHz. A torque of 0.5 mNm was reached at a maximum power of 45 mW with a speed of 45 rad/sec. The maximum efficiency was 16%.Article Norm Estimates of a Class of Calderon–zygmund Type Strongly Singular Integral Operators(Integral Transforms and Special Functions, 2007) Aksoy, Ümit; Çelebi, OkayIn this article, we prove the Lp boundedness of a class of Calderon–Zygmund type strongly singular operators. In particular, we give an estimate for the L2 norm of these operators in the unit disc of the complex plane.Article Citation - WoS: 40Citation - Scopus: 52Variable Structure Control of a Class of Uncertain Systems(Pergamon-elsevier Science Ltd, 2004) Efe, MÖ; Ünsal, C; Kaynak, O; Yu, XHThis brief paper proposes a method for tuning the parameters of a variable structure controller. The approach presented extracts the error at the output of the controller and applies a nonlinear tuning law using this error measure. The adaptation mechanism drives the state tracking error vector to the sliding hypersurface and maintains the sliding mode. In the simulations, the approach presented has been tested on the control of Dulling oscillator and the analytical claims have been justified under the existence of measurement noise, uncertainty and large nonzero initial errors. (C) 2003 Elsevier Ltd. All rights reserved.
