8,238 research outputs found
Collectif (1986) Aménagement et développement. Vers de nouvelles pratiques. Montréal, ACFAS, Cahiers de l’ACFAS, no 38, 199 p.
Response to comments on "Differential Sensitivity to Human Communication in Dogs, Wolves, and Human Infants."
The comments by Fiset and Marshall-Pescini et al. raise important methodological issues and propose alternative accounts for our finding of perseverative search errors in dogs. Not denying that attentional processes and local enhancement are involved in such object search tasks, we provide here new evidence and argue that dogs’ behavior is affected by a combination of factors, including specific susceptibility to human communicative signals
Group classification of (1+1)-Dimensional Schr\"odinger Equations with Potentials and Power Nonlinearities
We perform the complete group classification in the class of nonlinear
Schr\"odinger equations of the form
where is an arbitrary
complex-valued potential depending on and is a real non-zero
constant. We construct all the possible inequivalent potentials for which these
equations have non-trivial Lie symmetries using a combination of algebraic and
compatibility methods. The proposed approach can be applied to solving group
classification problems for a number of important classes of differential
equations arising in mathematical physics.Comment: 10 page
The direct evaluation of attosecond chirp from a streaking measurement
We derive an analytical expression, from classical electron trajectories in a
laser field, that relates the breadth of a streaked photoelectron spectrum to
the group-delay dispersion of an isolated attosecond pulse. Based on this
analytical expression, we introduce a simple, efficient and robust procedure to
instantly extract the attosecond pulse's chirp from the streaking measurement.Comment: 4 figure
Results for the response function determination of the Compact Neutron Spectrometer
The Compact Neutron Spectrometer (CNS) is a Joint European Torus (JET)
Enhancement Project, designed for fusion diagnostics in different plasma
scenarios. The CNS is based on a liquid scintillator (BC501A) which allows good
discrimination between neutron and gamma radiation. Neutron spectrometry with a
BC501A spectrometer requires the use of a reliable, fully characterized
detector. The determination of the response matrix was carried out at the Ion
Accelerator Facility (PIAF) of the Physikalisch-Technische Bundesanstalt (PTB).
This facility provides several monoenergetic beams (2.5, 8, 10, 12 and 14 MeV)
and a 'white field'(Emax ~17 MeV), which allows for a full characterization of
the spectrometer in the region of interest (from ~1.5 MeV to ~17 MeV. The
energy of the incoming neutrons was determined by the time of flight method
(TOF), with time resolution in the order of 1 ns. To check the response matrix,
the measured pulse height spectra were unfolded with the code MAXED and the
resulting energy distributions were compared with those obtained from TOF. The
CNS project required modification of the PTB BC501A spectrometer design, to
replace an analog data acquisition system (NIM modules) with a digital system
developed by the 'Ente per le Nuove tecnologie, l'Energia e l'Ambiente' (ENEA).
Results for the new digital system were evaluated using new software developed
specifically for this project.Comment: Proceedings of FNDA 201
X,Y,Z-Waves: Extended Structures in Nonlinear Lattices
Motivated by recent experimental and theoretical results on optical X-waves,
we propose a new type of waveforms in 2D and 3D discrete media -- multi-legged
extended nonlinear structures (ENS), built as arrays of lattice solitons (tiles
or stones, in the 2D and 3D cases, respectively). First, we study the stability
of the tiles and stones analytically, and then extend them numerically to
complete ENS forms for both 2D and 3D lattices. The predicted patterns are
relevant to a variety of physical settings, such as Bose-Einstein condensates
in deep optical lattices, lattices built of microresonators, photorefractive
crystals with optically induced lattices (in the 2D case) and others.Comment: 4 pages, 4 figure
Historiographies et Fédéralisme au Canada
Aquest article analitza les representacions històriques de dues de les principals comunitats nacionals del Canadà, és a dir, la comunitat canadencoanglesa i la comunitat quebequesa. En la historiografia canadencoanglesa es constata la presència d’un projecte nacional ambiciós. La construcció nacional canadenca suggereix l’existència d’un model de govern neutre malgrat que, si s’analitza amb atenció, es pot percebre que hi preval la dinàmica inversa. Els historiadors anglòfons del país han acostumat a presentar la concepció unitària del federalisme com la forma més perfecta del projecte integrador canadenc. Aquest federalisme integrador, i no emancipador, s’origina a partir de la visió centralitzadora de John A. Macdonald, un dels pares de la federació canadenca. Aquest enfocament s’ha mantingut durant més de 140 anys d’història en comú i continua sent, encara en l’actualitat, un dels principals esculls que han de superar les nacions minoritàries del Canadà. Per validar la seva tesi, els autors recorren a una extensa anàlisi que explora tres de les grans estratègies que utilitza el Govern central per mantenir la seva autoritat sobre els estats membres de la federació canadenca a llarg termini: l’ús del poder judicial, la centralització dels poders i la globalització. Les estratègies emprades han variat segons la conjuntura econòmica, els líders polítics i les relacions de força política respecte dels vincles entre la federació i les províncies.This article studies the historical representation of the two main national communities in Canada; that is, the English-Canadian and the French-Canadian. Throughout the history of the English Canadian community, one can see an ambitious national project. The national construction of Canada suggests the existence of a neutral model of government but, when looking at this carefully, it is possible to see something quite different. English-speaking historians from Canada have normally introduced the concept of a unitary federalism as the most perfect form of the Canadian integration project. This integrating federalism, that does not lead to emancipation, stems from the centralist views of John Macdonald, one of the fathers of Canadian federalism. This approach has been kept for over 140 years of common history and, to this date, continues to be one of the main obstacles for minority nations within Canada. To strengthen their thesis, the authors base their work on an extensive analysis exploring the three big strategies used by the central government to assert its authority on the member States of the Canadian Federation in the long term: using the judicial power, centralizing powers and globalization. The strategies used have varied depending on the economic scenario, political leaders and the political power relations regarding the links between the Federation and the provinces.Este artículo analiza las representaciones históricas de dos de las principales comunidades nacionales del Canadá, es decir, la comunidad canadienseinglesa y la comunidad quebequense. En la historiografía canadiense-inglesa se constata la presencia de un proyecto nacional ambicioso. La construcción nacional canadiense sugiere la existencia de un modelo de gobierno neutro aunque, si se analiza con atención, puede percibirse la prevalencia de la dinámica inversa. Los historiadores anglófonos del país suelen presentar la concepción unitaria del federalismo como la forma más perfecta del proyecto integrador canadiense. Este federalismo integrador, y no emancipador, se origina a partir de la visión centralizadora de John A. Macdonald, uno de los padres de la Federación canadiense. Este enfoque se ha mantenido durante más de 140 años de historia en común y sigue siendo, todavía en la actualidad, uno de los principales obstáculos que deben superar las naciones minoritarias del Canadá. Para validar su tesis, los autores recurren a un extenso análisis que explora tres de las grandes estrategias que utiliza el Gobierno central para mantener su autoridad sobre los Estados miembros de la Federación canadiense a largo plazo: el uso del poder judicial, la centralización de los poderes y la globalización. Las estrategias empleadas han variado según la coyuntura económica, los líderes políticos y las relaciones de fuerza política en lo que respecta a los vínculos entre la Federación y las provincias
Limits on Lorentz Violation from the Highest Energy Cosmic Rays
We place several new limits on Lorentz violating effects, which can modify
particles' dispersion relations, by considering the highest energy cosmic rays
observed. Since these are hadrons, this involves considering the partonic
content of such cosmic rays. We get a number of bounds on differences in
maximum propagation speeds, which are typically bounded at the 10^{-21} level,
and on momentum dependent dispersion corrections of the form v = 1 +-
p^2/Lambda^2, which typically bound Lambda > 10^{21} GeV, well above the Planck
scale. For (CPT violating) dispersion correction of the form v = 1 + p/Lambda,
the bounds are up to 15 orders of magnitude beyond the Planck scale.Comment: 24 pages, no figures. Added references, very slight changes. Version
published in Physical Review
Electric fan use during heat waves: Turn off for the elderly?
Comment on: Ravanelli NM, Jay O. Electric fan use in heat waves: Turn on or turn off?
Temperature. 2016;3:358–360. doi:10.1080/23328940.2016.1211073
- …