Search results for "Acceleration"
showing 10 items of 345 documents
Mass Measurements with the CSS2 and CIME cyclotrons at GANIL
2005
Commune avec ACEN; This paper presents two original direct mass-measurement techniques developed at GANIL using the CSS2 and CIME cyclotrons as high-resolution mass spectrometers. The mass measurement with the CSS2 cyclotron is based on a time-of-flight method along the spiral trajectory of the ions inside the cyclotron. The atomic mass excesses of 68Se and 80Y recently measured with this technique are -53.958(246) MeV and -60.971(180) MeV, respectively. The new mass-measurement technique with the CIME cyclotron is based on the sweep of the acceleration radio-frequency of the cyclotron. Tests with stable beams have been performed in order to study the accuracy of this new mass-measurement m…
High-Resolution Spectroscopy in Fast Atomic Beams
1977
Narrow optical resonances have been observed in fast beams of Na and Cs atoms, obtained from ion beams by charge-transfer collisions with Na, K, or Cs. Corresponding to the narrowing of the velocity distribution, occurring by acceleration, the Doppler width along the beam direction is considerably reduced [1, 2].
Elastic wave propagation in bone in vivo: methodology.
1995
The purpose of this study was to investigate the usefulness of elastic wave propagation (EWP) in estimating the mechanical properties (elasticity) of human tibia. The test group was composed of 78-yr-old women assigned to high (n = 19) and low (n = 17) bone mineral density (BMD) groups as measured at the calcaneus by the 125I-photon absorption method. The EWP apparatus consisted of an impact-producing hammer with a force strain gauge and two accelerometers positioned on the bone. Results for nylon and acrylic were used to calibrate the apparatus. Polyvinyl chloride (PVC) solid rods and tubes of various diameters were used to evaluate the relationship between the elastic wave velocity and cr…
Diagnostics for studies of novel laser ion acceleration mechanisms.
2014
Diagnostic for investigating and distinguishing different laser ion acceleration mechanisms has been developed and successfully tested. An ion separation wide angle spectrometer can simultaneously investigate three important aspects of the laser plasma interaction: (1) acquire angularly resolved energy spectra for two ion species, (2) obtain ion energy spectra for multiple species, separated according to their charge to mass ratio, along selected axes, and (3) collect laser radiation reflected from and transmitted through the target and propagating in the same direction as the ion beam. Thus, the presented diagnostic constitutes a highly adaptable tool for accurately studying novel accelera…
Silicon resonator sensors: interrogation techniques and characteristics
1988
Interferometric and noninterferometric optical-fibre sensing systems for resonator vibrations are described. The quality factor variation with pressure, the temperature dependence of resonant frequency and the acceleration sensitivity are given for a double-ended tuning-fork based acceleratometer.
Surface acceleration during dry laser cleaning of silicon
1999
We report on measurements of the surface acceleration for the application of dry laser cleaning. For that purpose, industrial silicon samples were irradiated by a frequency-doubled Q-switched Nd:YAG laser. The surface displacement was measured by a heterodyne interferometer and recorded by a digital storage oscilloscope. Several hundreds of shots were averaged to give smooth displacement curves which could be derived numerically. The experiments show that the highest accelerations, which are thought to be responsible for the cleaning, occur on the time scale of the laser pulse. Simple theoretical models are in good agreement with the experimental data. The maximal displacement depends only …
Bidirectional labeling in column-generation algorithms for pickup-and-delivery problems
2018
Abstract For the exact solution of many types of vehicle-routing problems, column-generation based algorithms have become predominant. The column-generation subproblems are then variants of the shortest-path problem with resource constraints which can be solved well with dynamic-programming labeling algorithms. For vehicle-routing problems with a pickup-and-delivery structure, the strongest known dominance between two labels requires the delivery triangle inequality (DTI) for reduced costs to hold. When the direction of labeling is altered from forward labeling to backward labeling, the DTI requirement becomes the pickup triangle inequality (PTI). DTI and PTI cannot be guaranteed at the sam…
40m sprint mechanics dataset male and female athletes UiA/Olympiatoppen
2020
This data is collected on over 600 Norwegian athletes from different sports performing 40m sprint tests under highly controlled conditions. The data was collected as part of training monitoring. The data forms the background for several published studies.
Effects of Kinesiotape® taping on plantar pressure and impact acceleration during walking
2014
Summary Objectives The aim of this study was to analyse the plantar pressure pattern, contact time, stride rate and impact acceleration in the shank during walking with and without Kinesio Tape (KT®) placed on two muscle groups: peroneus and triceps surae. Methods Among the subjects, 29 (12 men, 17 women) participated in the study. KT® was placed on the triceps surae and peroneus and participants walked at two different speeds (V1: 0.73 m/s; V2: 1.30 m/s) with and without KT®. The pedobarographic system Biofoot IBV® 6.0 was used to analyse plantar pressure (mean peak pressure [kPa]) in 5 foot areas and the kinematic variables of the study (contact time [s]; stride rate [steps/second]). One …
Dust Production and Particle Acceleration in Supernova 1987A Revealed with ALMA
2013
Supernova (SN) explosions are crucial engines driving the evolution of galaxies by shock heating gas, increasing the metallicity, creating dust, and accelerating energetic particles. In 2012 we used the Atacama Large Millimeter/Submillimeter Array to observe SN 1987A, one of the best-observed supernovae since the invention of the telescope. We present spatially resolved images at 450um, 870um, 1.4mm, and 2.8mm, an important transition wavelength range. Longer wavelength emission is dominated by synchrotron radiation from shock-accelerated particles, shorter wavelengths by emission from the largest mass of dust measured in a supernova remnant (>0.2Msun). For the first time we show unambig…