1,720,985 research outputs found

    Actuator with a non-contact position sensor

    No full text
    An actuator having a fixed part, a movable part movable with respect to the fixed part in a travelling direction, and a non-contact position sensor connected to the movable part to read the position of the movable part. The position sensor has a reading device connected to the fixed part and having a ferromagnetic core; and a magnetic cursor, which is integrated in the movable part, is defined by a magnetized portion of the movable part, and is so magnetized as to locally saturate the ferromagnetic core at the magnetic cursor

    Actuator with a non-contact position sensor

    No full text
    An actuator having a fixed part, a movable part movable with respect to the fixed part in a travelling direction, and a non-contact position sensor connected to the movable part to read the position of the movable part. The position sensor has a reading device connected to the fixed part and having a ferromagnetic core; and a magnetic cursor, which is integrated in the movable part, is defined by a magnetized portion of the movable part, and is so magnetized as to locally saturate the ferromagnetic core at the magnetic cursor

    Fuel pump operated by means of a shape memory material

    No full text
    A fuel pump for an internal combustion engine; the fuel pump is equipped with at least one pumping chamber with variable volume; with at least one inlet valve communicating with the pumping chamber; with at least one outlet valve communicating with the pumping chamber; with at least one flexible membrane that delimits the pumping chamber; and with an actuating device that acts on the flexible membrane to cyclically vary the volume of the pumping chamber; the actuating device presents at least one shape memory material thet modifies its geometry upon application of an external influence of a physical nature and is mechanically coupled with the flexible membrane, and a piloting device to cyclically apply an external influence of a physical nature to the shape memory material

    Choke device for an internal combustion engine intake system

    No full text
    A choke device for an intake system of an internal combustion engine; the choke device has at least one choke body fitted movably inside an intake conduit, and an actuating device for moving the choke body to and from a work position in which the choke body reduces the cross section of the intake conduit; and the actuating device has a filiform actuating member made of a shapememory material that changes shape when subjected to physical external stress, and having a first portion embedded in the choke body, and a second portion located outside the choke body and secured mechanically to a fixed part

    DESIGN OF A COMBINED PNEUMATIC AND MAGNETORHEOLOGICAL ACTUATOR FOR PROPORTIONAL MOTION CONTROL

    No full text
    This paper shows a solution based on the use of magnetorheological fluids, aimed at conferring proportional controllability to standard on-off pneumatic actuators. The central idea is based on adding a magnetorheological fluid brake on a standard pneumatic device, in order to achieve position control of the system. The goal is to design a small and cheap magnetorheological fluid brake for automotive applications . Several concept of brake are presented, using the fluid in shear and flow mode. The final configuration involves not only mechanical architecture, but also an investigation on the coil shape and the related magnetic field

    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

    Dispelling the Myths Behind First-author Citation Counts

    Full text link
    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods
    corecore