1,723,223 research outputs found

    Optimization of difference patterns for monopulse antennas by a hybrid real/integer-coded differential evolution method

    No full text
    Optimization of the difference patterns for monopulse antennas by a hybrid real/integer-coded differential evolution method Author(s): Caorsi, S (Caorsi, S); Massa, A (Massa, A); Pastorino, M (Pastorino, M); Randazzo, A (Randazzo, A) Source: IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION Volume: 53 Issue: 1 Pages: 372-376 DOI: 10.1109/TAP.2004.838788 Part: Part 2 Published: JAN 2005 Times Cited: 46 (from Web of Science) Cited References: 9 [ view related records ] Citation Map Abstract: The optimization of difference patterns of monopulse antennas is considered. The synthesis problem is recast as an optimization problem by defining a suitable cost function. In particular, in this paper, the cost function is based on constraints on the side-lobe levels. A subarray configuration is adopted and the excitations of the difference pattern are approximately determined. The optimization problem isefficiently solved by a differential evolution algorithm, which is able to contemporarily handle real and integer unknowns. Numerical results are reported concerning classical array configurations previously considered in the literature. Accession Number: WOS:000226261600014 Document Type: Article Language: English Author Keywords: array antennas; evolutionary algorithm; monopulse antennas; sum and difference patterns KeyWords Plus: SUM; ARRAYS Reprint Address: Caorsi, S (reprint author), Univ Pavia, Dept Elect, Via Palestro 3, I-27100 Pavia, Italy Addresses: 1. Univ Pavia, Dept Elect, I-27100 Pavia, Italy E-mail Address: [email protected] Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 445 HOES LANE, PISCATAWAY, NJ 08855-4141 USA Web of Science Category: Engineering, Electrical & Electronic; Telecommunications Subject Category: Engineering; Telecommunications IDS Number: 886VT ISSN: 0018-926

    Microwave medical imaging: potentialities and limitations of a stochastic optimization technique

    No full text
    Microwave medical imaging: Potentialities and limitations of a stochastic optimization technique Author(s): Caorsi, S (Caorsi, S); Massa, A (Massa, A); Pastorino, M (Pastorino, M); Rosani, A (Rosani, A) Source: IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES Volume: 52 Issue: 8 Pages: 1909-1916 DOI: 10.1109/tmtt.2004.832016 Part: Part 2 Published: AUG 2004 Times Cited: 14 (from Web of Science) Cited References: 29 [ view related records ] Citation Map Abstract: An approach based on a stochastic optimization technique is proposed for medical microwave imaging. The approach is based on the integral equations of the electromagnetic inverse scattering. After discretization of the continuous model, the problem solution is recast as a global optimization problem. A functional is constructed on the basis of a Markov random field model and minimized by a genetic algorithm. In order to reduce the computational load, a model of the cross section of the biological body is considered. In this way, the investigation area is limited by separating the scattering contribution of a fixed region under test from those of other parts of the model. Some preliminary results concerning a two-dimensional model of a human thorax are reported. Such a biological structure is inspected by the proposed tomographic approach in order to detect and localize the presence of an "object" modeling a tumor. Accession Number: WOS:000223051400007 Document Type: Article Language: English Author Keywords: genetic algorithms (GAs); inverse scattering; medical imaging; microwave imaging; optimization problems KeyWords Plus: BREAST-CANCER DETECTION; GENETIC ALGORITHMS; ELECTROMAGNETICS; TISSUES; MODEL Reprint Address: Rosani, A (reprint author), Univ Pavia, Dept Elect, I-27100 Pavia, Italy Addresses: 1. Univ Pavia, Dept Elect, I-27100 Pavia, Italy 2. Univ Trent, Dept Informat & Commun Technol, I-38050 Trent, Italy 3. Univ Genoa, Dept Biophys & Elect Engn, I-16145 Genoa, Italy E-mail Address: [email protected], [email protected], [email protected] Publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 445 HOES LANE, PISCATAWAY, NJ 08855 USA Web of Science Category: Engineering, Electrical & Electronic Subject Category: Engineering IDS Number: 843BW ISSN: 0018-948

    Going Beyond Counting First Authors in Author Co-citation Analysis

    Full text link
    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

    Full text link
    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

    Full text link
    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
    corecore