Francesca Dezi, Fabrizio Gara, Davide Roia
This paper presents some results of dynamic lateral loading tests on a near-shore steel pipe pile vibrodriven into soft marine clay. Two typologies of tests are carried out on a free head pile: impact load tests and free vibration tests at different load levels. The aim of this experimentation is to investigate the dynamic soil-water-pile interaction and determine the dynamic characteristics of the whole system by means of the two different typologies of test and for different levels of the dynamic input. The obtained results show the complex dynamic behaviour of the vibrating...
TC4 Symposium 2014
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Sami Kurtti, Juha Kostamovaara
A receiver channel topology for a pulsed time-of-flight (TOF) laser rangefinder is presented. The designed compact IC receiver chip realized in 0.35 μm CMOS technology will include both a highperformance receiver channel and a time-to-digital converter (TDC). Its timing detection is based on the leading edge detection in the receiver channel. Amplitude-dependent timing error is compensated for by utilizing multi-channel TDC for detecting the pulse width and the slew rate of the received pulse echo and by using this information for calibration. Based on Cadence simulations a timing accuracy...
TC4 Symposium 2014
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Linus Michaeli, Ján Šaliga, Marek Godla, Jozef Lipták
The paper presents method of the measurement of dielectric absorption components by the analysis of discharging exponential signal from the capacitor. The method uses maximum likelihood estimation as an alternative to the Prony’ s method. The advantage of the proposed method is the suppression of the uncertainties of recovering process caused by finite input resistance and vaguely defined discharging time. The possibility to minimize the effects of integral nonlinearities of Analog-to-Digital Converter is another advantage. The comparison of the experimental results with the simulation...
TC4 Symposium 2014
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Sebastian Emanuel Lauro, Elisabetta Mattei, Barbara Cosciotti, Federico di Paolo, Elena Pettinelli
We present the results obtained with a custom coaxial-cage line built to measure the complex dielectric permittivity and magnetic permeability of granular and/or liquid materials. The coaxial-cage line presents an open structure to facilitate the insertion and to control the compactness of granular materials. The measurements have been performed using a Vector Network Analyzer and the electromagnetic parameters of the samples have been retrieved through the Nicolson-Ross-Weir algorithm (in case of magnetic materials) or the Boughriet algorithm (in case of non-magnetic ones). The cell has...
TC4 Symposium 2014
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Luca Callegaro, Bruno Trinchera, Luca Roncaglione
A cryogenic magnetic current sensor has been constructed and tested for operation and sensitivity in the ac regime. The sensor is based on a ferromagnetic-core current transformer, coupled to a superconducting-quantum-interferencedevice (SQUID) current detector. The SQUID electronics provides a voltage output that can be coupled to roomtemperature signal recovery electronics, such as a lock-in amplifier. Working in liquid helium (4.2K) the sensor transresistance is about 1.8M in the audio frequency range; the equivalent input current noise of the sensor, at the frequency of 1 kHz, is a few...
TC4 Symposium 2014
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Laurent A. Francis, Sylvain Druart, Denis Flandre
In this paper, we present a methodology and a circuit to extract liquid mixtures resistance and capacitance simultaneously from the same output signal using interdigitated sensing electrodes. The principle is based on the triangular waveform voltage signal generation technique where a current square wave is applied to the sensor and results in a triangular output voltage that contains both the conductivity and permittivity parameters in a single periodic segment. A closed-loop current controlled oscillator that operates on a single DC power supply implements this concept. The system...
TC4 Symposium 2014
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Silvia Zorzetti, Manfred Wendt, Luca Fanucci
The Compact Linear Collider (CLIC) requires a low emittance beam transport and preservation, thus a precise control of the beam orbit along up to 50 km of the accelerator components in the sub-μm regime is required. Within the PACMAN (Particle Accelerator Components Metrology and Alignment to the Nanometer Scale) Ph.D. training action a study with the objective to pre-align the electrical center of a 15 GHz cavity BPM to the magnetic center of the main beam quadrupole is initiated. Goals, first ideas, some technical details, as well as the challenges of this stretched wire based method will...
TC4 Symposium 2014
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Andrea Mostacci, David Alesini, Nicolò Biancacci, Fritz Caspers, Luca Ficcadenti, Joseph Kuczerowski, Mauro Migliorati, Luigi Palumbo, Benoit Salvant, Bruno Spataro
Bench measurements nowadays represent an important tool to estimate the coupling impedance of any particle accelerator device. The well-known technique based on the coaxial wire method allows to excite in the device under test a field similar to the one generated by an ultra-relativistic point charge. We discuss the basics of the coaxial wire method and review the formulae widely used to convert measured scattering parameters to longitudinal and transverse impedance data. We review, as well, bead-pull technique used in the design, construction and tuning of multi-cell accelerating...
TC4 Symposium 2014
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Maria Pia Anania, Giancarlo Gatti, Marco Belleveglia, Enrica Chiadroni, Alessandro Cianchi, Domenico Di Giovenale, Giampiero Di Pirro, Andrea Mostacci, Riccardo Pompili, Cristina Vaccarezza, Fabio Villa, Massimo Ferrario
Novel particle accelerators are profiting from compact and high power lasers for beam generation or high gradient acceleration. Moreover, high brightness electron beams colliding with photons have paved the way to generate coherent X-ray radiation. Here we review the basic mechanism behind the generation of ultra-short high power laser system and in particular we report on laser beam characterisation at FLAME and STRATCLYDE, useful for particle acceleration driven by plasma. Eventually we discuss on the applications currently developed or under design at INFN-LNF in the frame of SPARC_LAB.
TC4 Symposium 2014
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Riccardo Pompili, Maria Pia Anania, Marco Bellaveglia, M. Castellano, Enrica Chiadroni, Alessandro Cianchi, Domenico Di Giovenale, Giampiero Di Pirro, Giancarlo Gatti, F. Giorgianni, Massimo Ferrario, F. Massimo, Andrea
At SPARC-LAB, we have installed an Electro-Optic Sampling (EOS) experiment for single shot, non-destructive measurements of the longitudinal distribution charge of individual electron bunches. The profile of the electron bunch field is electro-optically encoded into a Ti:Sa laser, having 130 fs (rms) pulse length, directly derived from the photocathode’s laser. The bunch profile information is spatially retrieved, i.e., the laser crosses with an angle of 30 deg with respect the normal to the surface of EO crystal (ZnTe, GaP) and the bunch longitudinal profile is mapped into the laser’s...
TC4 Symposium 2014
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