87,224 research outputs found
Damage detection in composite landing gear component using frequency response method
No full textIn this work, the damage identification for a composite landing gear component has been performed by the study of its dynamic behaviour. Fiber optic sensors were used for acquire the vibration signature of the system in its undamaged condition and during a high energy impact. The vibration test on the damaged component underlined a modification on the system response which should be considered for the health status assessment
Variations on the Author
No full text“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
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
Also By The Same Author: AKTiveAuthor, a Citation Graph Approach to Name Disambiguation
No full textThe desire for definitive data and the semantic web drive for inference over heterogeneous data sources requires co-reference resolution to be performed on those data. In particular, name disambiguation is required to allow accurate publication lists, citation counts and impact measures to be determined. This paper describes a graph-based approach to author disambiguation on large-scale citation networks. Using self-citation, co-authorship and document source analyses, AKTiveAuthor clusters papers, achieving precision of 0.997 and recall of 0.818 over a test group of eight surname clusters
Multichannel Approach for Arrayed Waveguide Grating-Based FBG Interrogation Systems
No full textIn this manuscript, an optically passive fiber Bragg grating (FBG) interrogation system able to perform high-frequency measurement is proposed. The idea is mainly based on the use of an arrayed waveguide grating (AWG) device which is used to discriminate the fiber optic sensor (FOS) wavelength encoded response under test in function of its output channels. As made clear by the theoretical model studied in the proposed manuscript, the Bragg wavelength shift can be detected as in linear dependence with the proposed interrogation function which changes with the voltage produced by two (or more) adjacent AWG output channels. To prove the feasibility of the system, some experimental analyses are conducted with a custom electrical module characterized by high-speed and low-noise operational amplifiers. As static measurements, three FBGs with different full width at half maximum (FWHM) have been monitored under wide-range wavelength variation; while, as dynamic measurement, one FBG, glued onto a metal plate, in order to sense the vibration at low and high frequency, was detected. The output signals have been processed by a digital acquisition (DAQ) board and a graphical user interface (GUI). The presented work highlights the characteristics of the proposed idea as competitor among the entire class of interrogation systems currently used. This is because here, the main device, that is the AWG, is passive and reliable, without the need to use modulation signals, or moving parts, that affect the speed of the system. In addition, the innovative multi-channel detection algorithm allows the use of any type of FOS without the need to have a perfectly match of spectra. Moreover, it is also characterized by a high dynamic range without loss of sensitivity
John F. Kennedy telegram to Roosevelt
No full textJersey Homesteads (later the Borough of Roosevelt) was established in the 1930s as an agro-industrial cooperative community. It was established specifically for urban Jewish garment workers, many of whom had emigrated from Europe. President John F. Kennedy sent a telegram to the citizens of Roosevelt, New Jersey, apologizing for not being able to attend the memorial dedication in honor of former President Franklin Delano Roosevelt. (Jersey Homesteads became Roosevelt in 1945 in honor of the president.) President Kennedy expressed his gratitude to the people of Roosevelt for constructing the memorial, and commented that it will serve as a constant reminder of Roosevelt's good works
Logarithmic variance profiles and the corresponding f-1 spectra of temperature fluctuations in turbulent Rayleigh-Bénard convection
No full textWe report experimental results for the temperature variance 2(z) and the corresponding frequency spectra P(f) in turbulent Rayleigh-Bénard convection (RBC) in a cylindrical sample of aspect ratioT= D/L = 1:00 (D = 1:12 m is the diameter and L = 1:12 m the height). The measurements were conducted in the Rayleigh-number range 1011 < Ra < 1:35 1014 and Pr ' 0:8. For Ra = 1:35x1014, 2(z) could be described well by a logarithmic dependence on the vertical position z in a range of z 1 < z < z 2 with z 1 ' 70 and z 2 = 0:1L. Here L=(2Nu) is the thickness of a thin thermal sublayer adjacent to the horizontal plate where the heat flux (denoted by the Nusselt number Nu) is carried mostly by thermal diffusion. In the log layer, we found that the temperature spectra had a significant frequency range over which P(f) f with close to 1. As Ra decreased, increased so that the log layer became thinner. At Ra = 2:05 1011, z 2 < z 1 and therefore there was no range for a log layer. Correspondingly, the temperature spectrum near the horizontal plate did not have the f1 scaling form either
Maine author Franklin F. Gould recalls his first glimpse of the outside world
No full textMaine author Franklin F. Gould recalls his first glimpse of the outside world as he relates how, as a young farm boy in the late 1800\u27s, he drove his father\u27s horses on an errand to an icebound river
Innovative safety monitoring system based on fiber optic sensors technology compatible with 4-20mA standard
No full textIn this contribution an innovative, full analog, fiber optic sensors (FOS) interrogator is designed which, being fully compatible with the 4-20 mA standard of the Programmable Logic Controller (PLC), enable the integration of the FOS technology in safety framework, such as the Detector Safety System (DSS) of the LHC Experiments. It is composed by a full analog electrical circuitry, capable to directly transduce the signal coming from the arrayed waveguide grating (AWG), into a monotonic electrical current in the range of 4-20mA. In a first experimental analysis, a temperature of 50°C was detected, exhibiting an output trend which can be fitted with a 3rd order polynomial equation over the whole range. Furthermore, in a reduced range of 20°C, the trend behaves linearly. The proposed system has the potential to be fully integrated in the DSS of the LHC experiments. Indeed, a validation on field is foreseen in the framework of the Compact Muon Solenoid experiment DSS
Simulation of an Optical-to-Digital Converter for High Frequency FBG Interrogator
No full textIn this paper, design and simulations of an optoelectronic circuit for the conversion of the optical signal, coming from an interrogation system for FBG sensors, into a digital signal, is presented. The approach is divided into an optical introduction of the interrogation system, an analog section and, finally, digital considerations. The analog processing part is mainly based on the realization of a double stage transimpedance amplifier to obtain, in the working conditions, the best performances required in terms of high gain and wide bandwidth. The output voltage from the analog section is then converted to digital via a 12-bit ADC and sent to an FPGA that processes the defined algorithm in order to obtain the needed optical-electrical linear conversion. The circuit simulations, digital stability and other consideration, including the stability to optical power variability obtained by the numerically simulated interrogation system, are performed, highlighting the peculiarities of this new type of high frequency FBG interrogator
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