2,078 research outputs found
Terms of Binding
The present dissertation aimed at achieving two goals. First, it constitutes an attempt to widen the search for phenomena that bear relevance to the idea that binding has a syntactic residue and is not, therefore, an exclusively semantic matter. Second, it tried to provide the technical means to account for these phenomena.
The case of the non-local binding of the Romanian bare reflexive sine (self) is used to back up the view that the syntactic residue of binding exists and should be extended so as to include A’-dependencies. Syntactically-encoded non-local binding is defined as a type of binding dependency that violates the Specified Subject Constraint. Non-locally bound anaphors, of the type instantiated by sine, are identified by a set of properties that include: subject orientation, c-command by both the local and the non-local antecedents and the restriction to the bound variable reading. There are diagnostics that point to the conclusion that non-local anaphors that meet these properties link up to their antecedents as the result of an A’-dependency having been established. The diagnostics include (i) the ungrammaticality of non-local binding out of adjunct islands and its very marginal acceptability out of relative clause islands and (ii) blocking of non-local binding by local wh-antecedents and quantified antecedents. The possibility of Romanian non-local sine to enter an A’-dependency with its non-local antecedents is determined by the morpho-syntactic properties of this bare reflexive form, i.e. by the feature specification it carries from the Lexicon
SAMPLE III SC.02 - Studying, sAmpling and Measuring of aircraft ParticuLate Emissions III: Specific Contract 02
The objectives of this specific contract were:
- to provide support to the SAE E-31 in drafting the Aerospace Recommended Practice (ARP) on the measurement of aircraft engine non-volatile particulate matter (nvPM) mass and number emissions; and
- to improve the sampling system that was manufactured during SAMPLE III SC.01 according to the preliminary specifications of the draft ARP, to assess its operating parameters at the SR Technics engine testing facility in Zürich and to perform a comparison with the sampling line installed at this facility.
In order to deliver the aforementioned objectives numerous design, experimental and desk based studies were performed:
- coordination of and contribution to SAE E-31 meetings and teleconferences;
- manufacture of a sampling system to allow remote operation and monitoring and simultaneous sampling within SR Technics test cell; and
- conduct numerous piggy back and dedicated engine test campaigns at SR Technics
Impact of fuel hydrogen content on non-volatile particulate matter emitted from an aircraft auxiliary power unit measured with standardised reference systems
© 2020 Replacement of conventional petroleum jet fuel with sustainable aviation fuels (SAFs) can significantly reduce non-volatile Particulate Matter (nvPM) emissions from aircraft main engines and auxiliary power units (APUs). As part of the Initiative Towards sustAinable Kerosene for Aviation (ITAKA) project, the impact of fuel hydrogen content on nvPM number and mass emissions and particle size distributions were investigated using a GTCP85 APU burning blends of conventional (Jet A-1) and Hydrotreated Esters and Fatty Acids (HEFA)-derived (Used Cooking Oil and Camelina) aviation fuels. The measurements were conducted during two separate test campaigns performed three years apart, each employing a different regulatory compliant sampling and measurement reference system for aircraft engine nvPM emissions. The objective was to investigate the correlation of fuel hydrogen content with nvPM number and mass emissions at the engine exit plane (EEP) independent of fuel composition, measurement system, and ambient conditions. The nvPM number and mass emissions and size distributions systematically decreased with increasing fuel hydrogen content regardless of the fuel composition or APU operating condition. The measured nvPM emissions were particle loss-corrected to the EEP and normalised to a common fuel hydrogen content. Similar rates of nvPM reductions were observed for both test campaigns at all investigated APU operating conditions, confirming that engine exit nvPM reductions correlate with fuel hydrogen content for fuels of relatively similar compositions. This analysis method can be applied to emissions data from other engine types to compare the reduction in nvPM emissions for sustainable aviation fuels and blends
Charge separation relative to the reaction plane in Pb-Pb collisions at TeV
Measurements of charge dependent azimuthal correlations with the ALICE
detector at the LHC are reported for Pb-Pb collisions at TeV. Two- and three-particle charge-dependent azimuthal correlations in
the pseudo-rapidity range are presented as a function of the
collision centrality, particle separation in pseudo-rapidity, and transverse
momentum. A clear signal compatible with a charge-dependent separation relative
to the reaction plane is observed, which shows little or no collision energy
dependence when compared to measurements at RHIC energies. This provides a new
insight for understanding the nature of the charge dependent azimuthal
correlations observed at RHIC and LHC energies.Comment: 12 pages, 3 captioned figures, authors from page 2 to 6, published
version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/286
Multiplicity dependence of jet-like two-particle correlations in p-Pb collisions at = 5.02 TeV
Two-particle angular correlations between unidentified charged trigger and
associated particles are measured by the ALICE detector in p-Pb collisions at a
nucleon-nucleon centre-of-mass energy of 5.02 TeV. The transverse-momentum
range 0.7 5.0 GeV/ is examined,
to include correlations induced by jets originating from low
momen\-tum-transfer scatterings (minijets). The correlations expressed as
associated yield per trigger particle are obtained in the pseudorapidity range
. The near-side long-range pseudorapidity correlations observed in
high-multiplicity p-Pb collisions are subtracted from both near-side
short-range and away-side correlations in order to remove the non-jet-like
components. The yields in the jet-like peaks are found to be invariant with
event multiplicity with the exception of events with low multiplicity. This
invariance is consistent with the particles being produced via the incoherent
fragmentation of multiple parton--parton scatterings, while the yield related
to the previously observed ridge structures is not jet-related. The number of
uncorrelated sources of particle production is found to increase linearly with
multiplicity, suggesting no saturation of the number of multi-parton
interactions even in the highest multiplicity p-Pb collisions. Further, the
number scales in the intermediate multiplicity region with the number of binary
nucleon-nucleon collisions estimated with a Glauber Monte-Carlo simulation.Comment: 23 pages, 6 captioned figures, 1 table, authors from page 17,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/161
Multi-particle azimuthal correlations in p-Pb and Pb-Pb collisions at the CERN Large Hadron Collider
Measurements of multi-particle azimuthal correlations (cumulants) for charged
particles in p-Pb and Pb-Pb collisions are presented. They help address the
question of whether there is evidence for global, flow-like, azimuthal
correlations in the p-Pb system. Comparisons are made to measurements from the
larger Pb-Pb system, where such evidence is established. In particular, the
second harmonic two-particle cumulants are found to decrease with multiplicity,
characteristic of a dominance of few-particle correlations in p-Pb collisions.
However, when a gap is placed to suppress such correlations,
the two-particle cumulants begin to rise at high-multiplicity, indicating the
presence of global azimuthal correlations. The Pb-Pb values are higher than the
p-Pb values at similar multiplicities. In both systems, the second harmonic
four-particle cumulants exhibit a transition from positive to negative values
when the multiplicity increases. The negative values allow for a measurement of
to be made, which is found to be higher in Pb-Pb collisions at
similar multiplicities. The second harmonic six-particle cumulants are also
found to be higher in Pb-Pb collisions. In Pb-Pb collisions, we generally find
which is indicative of a Bessel-Gaussian
function for the distribution. For very high-multiplicity Pb-Pb
collisions, we observe that the four- and six-particle cumulants become
consistent with 0. Finally, third harmonic two-particle cumulants in p-Pb and
Pb-Pb are measured. These are found to be similar for overlapping
multiplicities, when a gap is placed.Comment: 25 pages, 11 captioned figures, 3 tables, authors from page 20,
published version, figures at http://aliceinfo.cern.ch/ArtSubmission/node/87
A note on comonotonicity and positivity of the control components of decoupled quadratic FBSDE
In this small note we are concerned with the solution of Forward-Backward
Stochastic Differential Equations (FBSDE) with drivers that grow quadratically
in the control component (quadratic growth FBSDE or qgFBSDE). The main theorem
is a comparison result that allows comparing componentwise the signs of the
control processes of two different qgFBSDE. As a byproduct one obtains
conditions that allow establishing the positivity of the control process.Comment: accepted for publicatio
Transverse sphericity of primary charged particles in minimum bias proton-proton collisions at , 2.76 and 7 TeV
Measurements of the sphericity of primary charged particles in minimum bias
proton--proton collisions at , 2.76 and 7 TeV with the ALICE
detector at the LHC are presented. The observable is linearized to be collinear
safe and is measured in the plane perpendicular to the beam direction using
primary charged tracks with GeV/c in . The
mean sphericity as a function of the charged particle multiplicity at
mid-rapidity () is reported for events with different
scales ("soft" and "hard") defined by the transverse momentum of the leading
particle. In addition, the mean charged particle transverse momentum versus
multiplicity is presented for the different event classes, and the sphericity
distributions in bins of multiplicity are presented. The data are compared with
calculations of standard Monte Carlo event generators. The transverse
sphericity is found to grow with multiplicity at all collision energies, with a
steeper rise at low , whereas the event generators show the
opposite tendency. The combined study of the sphericity and the mean with multiplicity indicates that most of the tested event generators
produce events with higher multiplicity by generating more back-to-back jets
resulting in decreased sphericity (and isotropy). The PYTHIA6 generator with
tune PERUGIA-2011 exhibits a noticeable improvement in describing the data,
compared to the other tested generators.Comment: 21 pages, 9 captioned figures, 3 tables, authors from page 16,
published version, figures from
http://aliceinfo.cern.ch/ArtSubmission/node/308
Centrality dependence of charged particle production at large transverse momentum in Pb-Pb collisions at TeV
The inclusive transverse momentum () distributions of primary
charged particles are measured in the pseudo-rapidity range as a
function of event centrality in Pb-Pb collisions at
TeV with ALICE at the LHC. The data are presented in the range
GeV/ for nine centrality intervals from 70-80% to 0-5%.
The Pb-Pb spectra are presented in terms of the nuclear modification factor
using a pp reference spectrum measured at the same collision
energy. We observe that the suppression of high- particles strongly
depends on event centrality. In central collisions (0-5%) the yield is most
suppressed with at -7 GeV/. Above
GeV/, there is a significant rise in the nuclear modification
factor, which reaches for GeV/. In
peripheral collisions (70-80%), the suppression is weaker with almost independently of . The measured nuclear
modification factors are compared to other measurements and model calculations.Comment: 17 pages, 4 captioned figures, 2 tables, authors from page 12,
published version, figures at
http://aliceinfo.cern.ch/ArtSubmission/node/284
- …