1,509 research outputs found
Perturbations of the local gravity field due to mass distribution on precise measuring instruments: a numerical method applied to a cold atom gravimeter
We present a numerical method, based on a FEM simulation, for the
determination of the gravitational field generated by massive objects, whatever
geometry and space mass density they have. The method was applied for the
determination of the self gravity effect of an absolute cold atom gravimeter
which aims at a relative uncertainty of 10-9. The deduced bias, calculated with
a perturbative treatment, is finally presented. The perturbation reaches (1.3
\pm 0.1) \times 10-9 of the Earth's gravitational field.Comment: 12 pages, 7 figure
Epidural Volume of Injectate Using a Dose Regimen Based on Occipito-Coccygeal Spinal Length (OCL): Randomized Clinical Study Comparing Different Ropivacaine Concentrations, with or without Morphine, in Bitches Undergoing Total Unilateral Mastectomy
A prospective, randomized clinical trial was designed to compare four epidural treatments in dogs undergoing total unilateral mastectomy. The epidural volume of injectate was based on the individual occipito-coccygeal length (OCL) aiming to reach the first thoracic vertebra (T1). The first ten dogs were allocated in a control group (C) and did not receive epidural treatment. Subsequently, forty dogs were randomly allocated in four groups of ten: epidural ropivacaine 0.5% (R0.5%); morphine 0.1 mg kgâ1 plus ropivacaine 0.5% (MR0.5%); morphine 0.1 mg kgâ1 plus ropivacaine 0.35% (MR0.35%); morphine 0.1 mg kgâ1 plus ropivacaine 0.25% (MR0.25%). Intraoperatively, isoflurane requirement (1.3% vs. <1.1% FEâIso) and fentanyl requirement (9.8 vs. <1.1 ÎŒg kgâ1 hâ1) were significantly higher in C group compared to all epidural groups. Postoperatively, methadone requirement was higher (1.8 mg kgâ1 vs. <0.8 mg kgâ1) for C group compared to all epidural treatment groups. The ability to walk and to urinate returned 4 h earlier in MR0.35% and MR0.25%. The mean epidural volume of ropivacaine, using a dose regimen based on OCL, to reach T1 was about 0.15 mL cmâ1. The addition of morphine further reduced the methadone requirement, without affecting urinary and motor functions
Fabrication and characterization of etched facets in InP for advanced packaging of Photonic Integrated circuits
In this work we describe the fabrication and characterization of straight and angled etched facets compatible with the standard COBRA active-passive process. The implementation of these structures enables advanced packaging of photonic integrated circuits with multiple optical inputs and outputs
Fabrication and characterization of etched facets in InP for advanced packaging of Photonic Integrated circuits
In this work we describe the fabrication and characterization of straight and angled etched facets compatible with the standard COBRA active-passive process. The implementation of these structures enables advanced packaging of photonic integrated circuits with multiple optical inputs and outputs
Optimal Strategies in Infinite-state Stochastic Reachability Games
We consider perfect-information reachability stochastic games for 2 players
on infinite graphs. We identify a subclass of such games, and prove two
interesting properties of it: first, Player Max always has optimal strategies
in games from this subclass, and second, these games are strongly determined.
The subclass is defined by the property that the set of all values can only
have one accumulation point -- 0. Our results nicely mirror recent results for
finitely-branching games, where, on the contrary, Player Min always has optimal
strategies. However, our proof methods are substantially different, because the
roles of the players are not symmetric. We also do not restrict the branching
of the games. Finally, we apply our results in the context of recently studied
One-Counter stochastic games
Lattice gas model for fragmentation: From Argon on Scandium to Gold on Gold
The recent fragmentation data for central collisions of Gold on Gold are even
qualitatively different from those for central collisions of Argon on Scandium.
The latter can be fitted with a lattice gas model calculation. Effort is made
to understand why the model fails for Gold on Gold. The calculation suggests
that the large Coulomb interaction which is operative for the larger system is
responsible for this discrepancy. This is demonstrated by mapping the lattice
gas model to a molecular dynamics calculation for disassembly. This mapping is
quite faithful for Argon on Scandium but deviates strongly for Gold on Gold.
The molecular dynamics calculation for disassembly reproduces the
characteristics of the fragmentation data for both Gold on Gold and Argon on
Scandium.Comment: 13 pages, Revtex, 8 figures in ps files, submitted to Phys. Rev.
Fabrication and characterization of a wet-etched InP-based vertical coupling mirror
In this work we describe the fabrication and characterization of couplers realized with a wet etching process that is compatible with the standard COBRA active-passive process. The implementation of this broadband structure allows for wafer-scale waveguide-loss and absolute-wavelength measurements
Fabrication and characterization of a wet-etched InP-based vertical coupling mirror
In this work we describe the fabrication and characterization of couplers realized with a wet etching process that is compatible with the standard COBRA active-passive process. The implementation of this broadband structure allows for wafer-scale waveguide-loss and absolute-wavelength measurements
Isotopic and Microcanonical Temperatures in Nuclear Multifragmentation
A systematic comparison of different isotopic temperatures with the
thermodynamical temperature of a multifragment system is made on the basis of
the Statistical Multifragmentation Model. It is demonstrated that isotopic
temperatures are strongly affected by the secondary decays of hot primary
fragments and the population of particle-stable excited states in final
fragments. The He-Li temperatures, measured recently by the ALADIN group, are
reproduced fairly well both as a function of excitation energy and bound
charge. Our analysis confirms the anomaly in the nuclear caloric curve.Comment: 10 pages in LaTeX, 3 ps figures, accepted for publication in Phys.
Rev.
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