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O ajudante de acção directa na medida de rendimento social de inserção: um estudo de caso
Fonte: Instituto Superior de Ciências Sociais e Políticas
Publicador: Instituto Superior de Ciências Sociais e Políticas
Tipo: Dissertação de Mestrado
Publicado em 26/03/2010
Português
Relevância na Pesquisa
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#Rendimento Social de Inserção#Ajudante de Acção Directa#Intervenção social#Figura de proximidade#Descritivo funcional#Avaliação#Social Insertion Income#Direct Action Assistant#Social Work#Proximity Figure#Function Description
Dissertação de Mestrado em Política Social; A prevenção de situações de pobreza e exclusão bem como a promoção da autonomia e integração pessoal, social e comunitária constituem o objectivo primordial da Medida de Política Social de Rendimento Social de Inserção.
Este trabalho avalia o papel do Ajudante de Acção Directa na execução da Medida acima referida nos protocolos de acompanhamento de indivíduos e famílias estabelecidos entre o Instituto da Segurança Social e Instituições do Distrito de Setúbal, ao nível do seu desempenho profissional, enquanto interventor social integrado em equipas multidisciplinares, na relação com o Gestor de Caso e na relação com o sistema cliente.
Para a sua concretização, recolhemos dados por via da observação e da aplicação de inquéritos por questionário aplicados a 73 Ajudantes de Acção Directa e 43 Gestores de Caso, e por entrevista realizada a 34 Ajudantes de Acção Directa.
Foi possível identificar o grau de adequabilidade entre o descritivo funcional e a prática verificada, bem como elencar as potencialidades, constrangimentos e formas de superação dos mesmos referentes ao Ajudante de Acção Directa na execução da Medida RSI.
Percebemos que este interventor social representa uma figura de proximidade determinante na prossecução dos objectivos e metodologias de intervenção definidas para esta Medida; The prevention of poverty situations...
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A Century of Gestalt Psychology in Visual Perception I. Perceptual Grouping and Figure-Ground Organization
Fonte: PubMed
Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
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In 1912, Max Wertheimer published his paper on phi motion, widely recognized as the start of Gestalt psychology. Because of its continued relevance in modern psychology, this centennial anniversary is an excellent opportunity to take stock of what Gestalt psychology has offered and how it has changed since its inception. We first introduce the key findings and ideas in the Berlin school of Gestalt psychology, and then briefly sketch its development, rise, and fall. Next, we discuss its empirical and conceptual problems, and indicate how they are addressed in contemporary research on perceptual grouping and figure-ground organization. In particular, we review the principles of grouping, both classical (e.g., proximity, similarity, common fate, good continuation, closure, symmetry, parallelism) and new (e.g., synchrony, common region, element and uniform connectedness), and their role in contour integration and completion. We then review classic and new image-based principles of figure-ground organization, how it is influenced by past experience and attention, and how it relates to shape and depth perception. After an integrated review of the neural mechanisms involved in contour grouping, border-ownership, and figure-ground perception...
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Comment on "Anomalous proximity effect in underdoped YBa_2Cu_3O_{6+x} Josephson junctions"
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/01/2003
Português
Relevância na Pesquisa
27.094114%
In recent photodoping experiments Decca et al. [PRL 85, 3708 (2000)] have
observed an unusually long-ranged proximity effect between the superconducting
and insulating phases of YBCO. Here we critically examine the claim in that
reference that such long range is anomalous. We show that, once the novel
nature of the experiments has been properly accounted for, the conventional
theory of the proximity effect predicts comparably long ranges.; Comment: RevTeX4, 1 page, 1 figure. Accepted by Phys. Rev. Lett
Link permanente para citações:
Coulomb Blockade of Proximity Effect at Large Conductance
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.20208%
We consider the proximity effect in a normal dot coupled to a bulk
superconducting reservoir by the tunnel contact with large normal conductance.
Coulomb interaction in the dot suppresses the proximity minigap induced in the
normal part of the system. We find exact expressions for the thermodynamic and
tunneling minigaps as functions of the junction's capacitance. The tunneling
minigap interpolates between its proximity-induced value in the regime of weak
Coulomb interaction to the Coulomb gap in the regime of strong interaction. In
the intermediate case a non-universal two-step structure of the tunneling
density of states is predicted. The charge quantization in the dot is also
studied.; Comment: 4 pages (RevTeX), 3 figures. Version 2: minor corrections, a figure
and two references added
Link permanente para citações:
Lateral Casimir Force between Two Sinusoidally Corrugated Eccentric Cylinders Using Proximity Force Approximation
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 15/02/2014
Português
Relevância na Pesquisa
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This paper is devoted to the presentation of the lateral Casimir force
between two sinusoidally corrugated eccentric cylinders. Despite that applying
scattering matrix method explains the problem exactly, procedure of applying
this method is somehow complicated specially at nonzero temperature. Using the
proximity force approximation (PFA) helps to achieve the lateral Casimir force
in a truly explicit manner. We assume the cylinders to be slightly eccentric
with similar radiuses and separations much smaller than corrugations' wave
length for the validity of PFA. For such short distances the effect of finite
conductivity would be non negligible. In addition to the effect of finite
conductivity, we investigate thermal corrections of the lateral Casimir force
to reduce the inaccuracy of the result obtained by PFA. Assuming the Casimir
force density between two parallel plates, the normal Casimir force between two
cylinders is obtained. With the aid of additive summation of the Casimir energy
between cylinders without corrugation, we obtain the lateral Casimir force
between corrugated cylinders.; Comment: 12 pages, 1 figure
Link permanente para citações:
Theory of the proximity effect in junctions with unconventional superconductors
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
26.918667%
We present a general theory of the proximity effect in junctions between
diffusive normal metals (DN) and unconventional superconductors in the
framework of the quasiclassical Green's function formalism. Various possible
symmetry classes in a superconductor are considered which are consistent with
the Pauli principle: even-frequency spin-singlet even-parity (ESE) state,
even-frequency spin-triplet odd-parity (ETO) state, odd-frequency spin-triplet
even-parity (OTE) state and odd-frequency spin-singlet odd-parity (OSO) state.
For each of the above four cases symmetry and spectral properties of the
induced pair amplitude in the DN are determined. It is shown that the pair
amplitude in a DN belongs respectively to an ESE, OTE, OTE and ESE pairing
state.; Comment: 5 pages with one figure
Link permanente para citações:
Interband proximity effect and nodes of superconducting gap in Sr2RuO4
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/02/2001
Português
Relevância na Pesquisa
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The power-law temperature dependences of the specific heat, the nuclear
relaxation rate, and the thermal conductivity suggest the presence of line
nodes in the superconducting gap of Sr2RuO4. These recent experimental
observations contradict the scenario of a nodeless (k_x+ik_y)-type
superconducting order parameter. We propose that interaction of superconducting
order parameters on different sheets of the Fermi surface is a key to
understanding the above discrepancy. A full gap exists in the active band,
which drives the superconducting instability, while line nodes develop in
passive bands by interband proximity effect.; Comment: 4 pages, 1 figure
Link permanente para citações:
Application of the proximity force approximation to gravitational and Yukawa-type forces
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/03/2009
Português
Relevância na Pesquisa
27.20208%
We apply the proximity force approximation, which is widely used for the
calculation of the Casimir force between bodies with nonplanar boundary
surfaces, to gravitational and Yukawa-type interactions. It is shown that for
the gravitational force in a sphere-plate configuration the general formulation
of the proximity force approximation is well applicable. For a Yukawa-type
interaction we demonstrate the validity of both the general formulation of the
proximity force approximation, and a simple mapping between the sphere-plate
and plate-plate configurations. The claims to the contrary in some recent
literature are thus incorrect. Our results justify the constraints on the
parameters of non-Newtonian gravity previously obtained from the indirect
dynamic measurements of the Casimir pressure.; Comment: 13 pages, 1 figure
Link permanente para citações:
Casimir forces beyond the proximity approximation
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/10/2011
Português
Relevância na Pesquisa
26.918667%
The proximity force approximation (PFA) relates the interaction between
closely spaced, smoothly curved objects to the force between parallel plates.
Precision experiments on Casimir forces necessitate, and spur research on,
corrections to the PFA. We use a derivative expansion for gently curved
surfaces to derive the leading curvature modifications to the PFA. Our methods
apply to any homogeneous and isotropic materials; here we present results for
Dirichlet and Neumann boundary conditions and for perfect conductors. A Pad\'e
extrapolation constrained by a multipole expansion at large distance and our
improved expansion at short distances, provides an accurate expression for the
sphere-plate Casimir force at all separations.; Comment: 4 pages, 1 figure
Link permanente para citações:
Proximity fingerprint of s+- superconductivity
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
26.918667%
We suggest a straightforward and unambiguous test to identify possible
opposite signs of superconducting order parameter in different bands proposed
for iron-based superconductors (s+- state). We consider proximity effect in a
weakly coupled sandwich composed of a s+- superconductor and thin layer of
s-wave superconductor. In such system the s-wave order parameter is coupled
differently with different s+- gaps and it typically aligns with one of these
gaps. This forces the other s+- gap to be anti-aligned with the s-wave gap. In
such situation the aligned band induces a peak in the s-wave density of states
(DoS), while the anti-aligned band induces a dip. Observation of such
contact-induced negative feature in the s-wave DoS would provide a definite
proof for s+- superconductivity.; Comment: 4 pages, one figure
Link permanente para citações:
Driven superconducting proximity effect in interacting quantum dots
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.094114%
We present a theory of non-equilibrium superconducting proximity effect in an
interacting quantum dot induced by a time-dependent tunnel coupling between dot
and a superconducting lead. The proximity effect, that is established when the
driving frequency fulfills a gate-voltage-dependent resonance condition, can be
probed through the tunneling current into a weakly-coupled normal lead.
Furthermore, we propose to generate and manipulate coherent superpositions of
quantum-dot states with electron numbers differing by two, by applying pulsed
oscillatory variations to the couplings between dot and superconductors.; Comment: 6 pages, 5 figures, paper substantially extended: new section, new
figure, new references introduced
Link permanente para citações:
Strongly far proximity and hyperspace topology
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.20208%
This article introduces strongly far proximity, which is associated with
Lodato proximity $\delta$. A main result in this paper is the introduction of a
hit-and-miss topology on $\mbox{CL}(X)$, the hyperspace of nonempty closed
subsets of $X$, based on the strongly far proximity.; Comment: 6 pages, 1 figure
Link permanente para citações:
Proximity Effect in Gold Coated $YBa_2Ca_3O_{7-\delta}$ Films Studied by Scanning Tunneling Spectroscopy
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 07/07/2003
Português
Relevância na Pesquisa
27.20208%
Scanning tunneling spectroscopy on gold layers over-coating \textit{c}-axis
$YBa_2Ca_3O_{7-\delta}$ (YBCO) films reveals proximity induced gap structures.
The gap size reduced exponentially with distance from \textit{a}-axis facets,
indicating that the proximity effect is primarily due to the (100) YBCO facets.
The penetration depth of superconductivity into the gold is $\sim 30$ nm, in
good agreement with estimations for the dirty limit. The extrapolated gap at
the interface is $\sim 15$ meV, consistent with recent point-contact
experiments. The proximity-induced order parameter appears to have predominant
\textit{s}-wave symmetry.; Comment: 4 revtex pages, 3 figure
Link permanente para citações:
Singlet-triplet conversion and the long-range proximity effect in superconductor-ferromagnet structures with generic spin dependent fields
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.094114%
The long-range proximity effect in superconductor/ferromagnet (S/F) hybrid
nano-structures is observed if singlet Cooper pairs from the superconductor are
converted into triplet pairs which can diffuse into the fer- romagnet over
large distances. It is commonly believed that this happens only in the presence
of magnetic inhomogeneities. We show that there are other sources of the
long-range triplet component (LRTC) of the con- densate and establish general
conditions for their occurrence. As a prototypical example we consider first a
system where the exchange field and spin-orbit coupling can be treated as time
and space components of an effective SU(2) potential. We derive a SU(2)
covariant diffusive equation for the condensate and demonstrate that an
effective SU(2) electric field is responsible for the long-range proximity
effect. Finally, we extend our analysis to a generic ferromagnet and establish
a universal condition for the LRTC. Our results open a new avenue in the search
for such correlations in S/F structures and make a hitherto unknown connection
between the LRTC and Yang-Mills electrostatics.; Comment: 5 pages; 1 Figure; updated file with new references
Link permanente para citações:
Dual proximity effect near superconductor-insulator transition
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.094114%
We show that quantum vortex-loop proliferation may be one possible
explanation of the super-long-range proximity effect observed in an insulating
underdoped cuprate, using the dual theory of quantum vortices. As a test of
this scenario, we propose that a dual proximity effect experiment can confirm
the superfluid motion of the quantum vortices in the vortex-proliferated
insulator and can measure the divergent correlation lengths near the
superconductor-insulator transition.; Comment: 4 pages, 1 eps figure; revised presentation
Link permanente para citações:
Calculation of cluster decays half-lives for nuclei between 56 < Zp < 120 by using temperature dependent proximity model
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 20/08/2014
Português
Relevância na Pesquisa
27.094114%
Cluster decays half-lives of elements with proton numbers between 56 < Zp <
120 are calculated by applying temperature dependent proximity potential
approach. for showing the influence of temperature on cluster decays, we
compared the results among temperature dependent and inde-pendent case with
experimental values. The obtained results of the present investigation reveal
that we have more accurate results for temperature dependent proximity
potential in comparison to ignoring one. In the present work, we find that
results provided with temperature dependent prox-imity model are reasonable
estimates for cluster decays half-lives and provide reliable predictions for
other super heavies cluster decays.; Comment: 15 pages, 1 figure
Link permanente para citações:
Thermal screening at finite chemical potential on a topological surface and its interplay with proximity-induced ferromagnetism
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.20208%
Motivated by recent experiments on EuS/Bi$_2$Se$_3$ heterostructures, we
study the temperature dependent screening effects on the surface of a
three-dimensional topological insulator proximate to a ferromagnetically
ordered system. In general, we find that besides the chemical potential and
temperature, the screening energy scale also depends on the proximity-induced
electronic gap in an essential way. In particular, at zero temperature the
screening energy vanishes if the chemical potential is smaller than the
proximity-induced electronic gap. We show that at finite temperature, $T$,
and/or chemical potential, $\mu$, the Chern-Simons (topological) mass, which is
generated by quantum fluctuations arising from the proximity-effect, can be
calculated analytically in the insulating regime. In this case the topological
mass yields the Hall conductivity associated to edge states. We show that when
the chemical potential is inside the gap the topological mass remains nearly
quantized at finite temperature.; Comment: 5 pages, 1 figure; v3: extended version; improved discussion of the
Hall conductivity at finite temperature
Link permanente para citações:
Proximity effects in the superconductor / heavy fermion bilayer system Nb / CeCu_6
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 19/03/2003
Português
Relevância na Pesquisa
27.094114%
We have investigated the proximity effect between a superconductor (Nb) and a
'Heavy Fermion' system (CeCu_6) by measuring critical temperatures $T_c$ and
parallel critical fields H_{c2}^{\parallel}(T) of Nb films with varying
thickness deposited on 75 nm thick films of CeCu_6, and comparing the results
with the behavior of similar films deposited on the normal metal Cu. For Nb on
CeCu_6 we find a strong decrease of T_c with decreasing Nb thickness and a
finite critical thickness of the order of 10 nm. Also, dimensional crossovers
in H_{c2}^{\parallel}(T) are completely absent, in strong contrast with Nb/Cu.
Analysis of the data by a proximity effect model based on the Takahashi-Tachiki
theory shows that the data can be explained by taking into account both the
high effective mass (or low electronic diffusion constant), {\it and} the large
density of states at the Fermi energy which characterize the Heavy Fermion
metal.; Comment: 7 pages, 2 figure. Manuscript has been submitted to a refereed
journal
Link permanente para citações:
Andreev Reflection and Proximity effect
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.094114%
The Andreev Reflection is the key mechanism for the superconducting proximity
effect. It provides phase correlations in a system of non-interacting electrons
at mesoscopic scales, i.e. over distances much larger than the microscopic
lengths : Fermi wavelength and elastic electron mean free path. This field of
research has attracted an increasing interest in the recent years in part
because of the tremendous development of nanofabrication technologies, and also
because of the richness of the involved quantum effects. In this paper we
review some recently achieved advances. We also discuss new open questions, in
particular non-equilibrium effects and proximity effect in systems with
ferromagnetic elements.; Comment: 17 pages, no figure, to appear in J. of Low Temp. Phys., proceeding
of the LT satellite conference "Electron Transport in Mesoscopic Systems",
reference list corrected
Link permanente para citações:
Spin-dependent Proximity Effects in d-wave Superconductor/Half-metal Heterostructures
Fonte: Universidade Cornell
Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/11/2005
Português
Relevância na Pesquisa
27.20208%
We report on mutual proximity effects in d-wave superconductor/half-metal
heterostructures which correspond to systems composed of high-Tc cuprates and
manganite materials. In our study, proximity effects are induced by the
interplay of two separate interface effects: spin-mixing (or rotation) surface
scattering and spin-flip scattering. The surface spin-mixing scattering
introduces spin-triplet pairing correlations in superconducting side; as a
result, Andreev bound states are formed at energies within the superconducting
gap. The spin-flip scattering introduces not only long range equal-spin pairing
amplitudes in the half-metal, but also an exotic magnetic proximity effect
extending into the superconductor.; Comment: 2 pages, 1 figure, submitted to 24th International Conference on Low
Temperature Physics
Link permanente para citações: