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Now showing 1 - 10 of 22
  • Article
    Citation - WoS: 42
    Citation - Scopus: 47
    Modified 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, Vimal
    A 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: 102
    Citation - Scopus: 113
    A 1.6-Mm, Metal Tube Ultrasonic Motor
    (Ieee-inst Electrical Electronics Engineers inc, 2003) Cagatay, S; Koc, B; Uchino, K
    A 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
    Citation - WoS: 6
    Citation - Scopus: 8
    Hybrid Electrooptic and Piezoelectric Laser Beam Steering in Two Dimensions
    (Ieee-inst Electrical Electronics Engineers inc, 2005) Scrymgeour, DA; Koc, B; Tian, LL; Gentzel, MW; Uchino, K; Gopalan, V
    With modern optical technology, there is a great demand for devices capable of steering a laser beam. at high speed. A hybrid electrooptical scanner and an electromechanical scanner capable of two-dimensional (2-D) laser beam scanning Eire demonstrated. This device can scan a laser beam in 2-D. A V scanning angle in the horizontal axis at 50 Hz using electrooptic scanning and a 5.23 degrees scanning angle in vertical axis at 25.6 kHz using piezoelectric scanning are shown.
  • Article
    Citation - WoS: 63
    Citation - Scopus: 98
    Improved Routh-Pade Approximants: a Computer-Aided Approach
    (Ieee-inst Electrical Electronics Engineers inc, 2004) Singh, V; Chandra, D; Kar, H
    A geometric programming based computer-aided method to derive a reduced order (rth-order) approximant for a given (stable) SISO linear continuous-time system is presented. In this method, stability and the first r time moments/Markov parameters are preserved as well as the errors between a set of subsequent time moments/Markov parameters of the system and those of the model are minimized.
  • Article
    Citation - WoS: 12
    Citation - Scopus: 17
    Limit and Application Range of the Slope-Diffraction Method for Wireless Communications
    (Ieee-inst Electrical Electronics Engineers inc, 2003) Kara, A; Bertoni, HL; Yazgan, E
    Limitations on the use of the uniform theory of diffraction (UTD) slope-diffraction. method for propagation past knife edges are investigated. The settled field that is diffracted past rows of buildings, as computed by numerical integration, has the characteristics of amplitude and phase variation with a scale length that is large compared to wavelength and,has small amplitude near the edges. Using this field, it is shown that the error in the UTD slope-diffraction method for diffraction past a final screen is connected with the Fresnel width, as compared to the scale length of the settled
  • Article
    Citation - WoS: 9
    Citation - Scopus: 11
    Food Index: a Multidimensional Index Structure for Similarity-Based Fuzzy Object Oriented Database Models
    (Ieee-inst Electrical Electronics Engineers inc, 2008) Yazici, Adnan; Ince, Cagri; Koyuncu, Murat
    A fuzzy object-oriented data model is a fuzzy logic-based extension to an object-oriented database model that permits uncertain data to be explicitly represented. The fuzzy object-oriented database (FOOD) model is one of the proposed models in the literature to handle uncertainty in object-oriented databases. Several kinds of fuzziness are dealt with in the FOOD model, including fuzziness at attribute level and between object and class and between class and superclass relations. The traditional index structures do not allow efficient access to both crisp and fuzzy objects for fuzzy object-oriented databases since they are not efficient enough in processing both crisp and fuzzy queries. In this study, we propose a new index structure, namely a FOOD index (FI), to deal with different kinds of fuzziness in fuzzy object-oriented databases and to support multidimensional indexing. In this paper, we describe this proposed index structure and show how it supports various types of flexible queries, and evaluate its performance for exact, range, and fuzzy queries.
  • Article
    Citation - WoS: 193
    Citation - Scopus: 211
    A Generalized Lmi-Based Approach To the Global Asymptotic Stability of Delayed Cellular Neural Networks
    (Ieee-inst Electrical Electronics Engineers inc, 2004) Singh, V
    A novel linear matrix inequality (LMI)-based criterion for the global asymptotic stability and uniqueness of the equilibrium point of a class of delayed cellular neural networks (CNNs) is presented. The criterion turns out to be a generalization and improvement over some previous criteria.
  • Article
    Citation - WoS: 25
    Citation - Scopus: 27
    Robust stability of 2-D digital filters employing saturation
    (Ieee-inst Electrical Electronics Engineers inc, 2005) Singh, V
    A computationally tractable, i.e., linear matrix inequality (LMI)-based criterion for the global asymptotic stability of uncertain two-dimensional digital filters described by the Fornasini-Marchesini second local state-space model with saturation overflow arithmetic is presented. The criterion is compared with an earlier LMI-based criterion.
  • Editorial
    Citation - WoS: 4
    Citation - Scopus: 4
    Comments on "global Robust Stability of Delayed Neural Networks"
    (Ieee-inst Electrical Electronics Engineers inc, 2006) Singh, V
    A recently reported result concerning the global robust stability of the equilibrium point of Hopfield-type delayed neural networks is revisited. It is shown that the result is not always right.
  • Article
    Citation - Scopus: 2
    Regularization-Based Error Concealment in Jpeg 2000 Coding Scheme
    (Ieee-inst Electrical Electronics Engineers inc, 2007) Oktem, Rusen
    This letter offers a solution to bit-error recovery for high-frequency subbands at high decomposition levels of JPEG 2000 bitstreams, with a novel perspective. Being inspired by the regularization approach, corrupted coefficients are estimated by imposing a smoothness constraint on the gradient of the reconstructed data. The approach can be generalized to other compression engines as well. Experimental results show that the proposed method achieves the best reported results so far, with up to 6 dB of PSNR improvement. The method does not require any parameter tuning, however, it does require numerical minimization.