1,720,964 research outputs found
A NEW THREE DEGREES-OF-FREEDOM MOTION SENSOR BASED ON LASER SELF-MIXING WITH PIGTAILED SOURCES
No full textReal time simultaneous measurement by remote laser source of long range longitudinal displacement and small angle wobbling of a sliding target is demonstrated. The compact self-aligned laser-self-mixing interferometer achieves 0.8 μm axial resolution over 1 m linear and 17 μrad of pitch and yaw resolution over 2 mrad angular ranges, respectively
A NO-CONTACT LASER SENSOR BASED ON THE SELF- MIXING EFFECT FOR THE MEASUREMENT OF ROTATIONS
No full textComparison of plane mirror vs retroreflector performance for laser-self-mixing displacement sensors
No full textThe behavior of a displacement optical sensor based on the Laser-Self-Mixing effect employing a plane mirror (PT) and a solid corner-cube (CC) as moving target is analyzed. The performance of the sensor is compared in terms of simplification of the optical setup, measurement accuracy and tolerance to angular misalignment of the target. On the basis of the innovative assumption that only the fraction of the laser beam orthogonal to the target plane gives rise to the Self – Mixing modulation, it is demonstrated that the interferometer tolerates small tilt of the plane target (up to approximately 0.7◦) only when illuminated by a divergent beam, in which case the displacement measurement becomes affected by a cosine – type error. Instead the corner cube preserves the self-mixing signal over a larger angular range (up to approximately 2◦) at the same time preserving high measurement accuracy
A compact three degrees-of-freedom motion sensor based on the laser-self-mixing effect
No full textThe simultaneous measurement of the linear displacement
and two rotation angles (yaw and pitch) of a moving object
using a laser sensor based on the self-mixing effect is reported. The laser head includes three commercial diode lasers equipped with
monitor photodiodes. The target is a plane mirror attached to the moving object. The linear and angular resolutions are 0.7 um and 0.008° (2.7 arcsec), respectively. The linearity of the sensor response has been verified over a range of 1 m and 0.4°. Using three retroreflector prisms with a diameter of 10mminstead of the plane mirror, the angular range of yaw and pitch has been improved by one order of magnitude
Comparison of plane mirror vs retroreflector performance for laser-self-mxing displacemen sensor
No full textRecenti acquisizioni per la modulazione della spasticità: somministrazione intratecale di miscele di farmaci
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
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