374 research outputs found
Leader trustworthy behavior and organizational trust: the role of the immediate manager for cultivating trust
This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.Drawing from both trust-building theory and interpersonal trust literature, we investigate how trust between a leader and follower may be leveraged to influence organizational trust. We also explore the mediating mechanisms of this link and test a potential moderator. A cross-sectional, multifoci design was adopted and participants were 201 employees within a public sector organization. Leader trustworthy behavior was found to predict organizational trust, mediated by trustworthiness perceptions and trust in the leader. Support for the boundary condition was found; namely, when leaders were more senior, the relationship between trustworthy behavior and organizational trust was stronger. The findings suggest that leaders can meaningfully influence organizational trust perceptions through the enactment of trustworthy behavior, although the strength of this effect varied as a function of their position
Low-cost multipurpose sensor network integrated with iot and webgis for fire safety concerns
Fire emergencies cause severe damage to Brazilian federal universities. An appropriate and efficient tool to prevent or detect such events early is multisensory networks from the Internet of Things (IoT). In this study, we present the stages of development of a WebGIS system which integrates the IoT that allows the detection and helps manage such incidents. The approach consists of a network of multipurpose sensors that can identify different sources of fire hazards. If a potential source is registered, information about environmental conditions is transmitted in real-time to the system. Depending on the severity level, an alert is issued to WebGIS. Location is represented on a map. The entire system consists of single-board devices. Software components are based on open-source tools. The whole network only needs little power and, therefore, theoretically, could be carried out as an autonomous system powered by batteries. The entire system has been tested with flame, temperature, gas, smoke, and humidity sensors. The experiments allowed us to show its potential, formulate recommendations and indications for future studies
Supercurrent induced domain wall motion
We study the dynamics of a magnetic domain wall, inserted in, or juxtaposed
to, a conventional superconductor, via the passage of a spin polarized current
through a FSF junction. Solving the Landau-Lifshitz-Gilbert equation of motion
for the magnetic moments we calculate the velocity of the domain wall and
compare it with the case of a FNF junction. We find that in several regimes the
domain wall velocity is larger when it is driven by a supercurrent.Comment: 10 pages, 8 figure
Fermi surfaces of iron-pnictide high-Tc superconductors from the limit of local magnetic moments
A 2-orbital t-J model over the square lattice that describes low-energy
electronic excitations in iron-pnictide high-Tc superconductors is analyzed
with Schwinger-boson-slave-fermion meanfield theory and by exact numerical
diagonalization on a finite system. A quantum critical point (QCP) is
identified that separates a commensurate spin-density wave (cSDW) state at
strong Hund's rule coupling from a hidden half-metal state at weak Hund's rule
coupling when inter-orbital hole hopping is suppressed. Low-energy spinwaves
that disperse anisotropically from cSDW momenta are predicted at the QCP.
Nested Fermi surfaces similar to those observed experimentally in iron-pnictide
materials are also predicted in such case.Comment: 11 pages, 3 figures, published versio
Estudo do polimorfismo do gene do hormônio de crescimento em rebanhos da raça Nelore do estado da Bahia.
Título em inglês: Study of the polymorphism of the gene of the hormone of growth in a Nelore breed of the state of the Bahia
Mixed-valent regime of the two-channel Anderson impurity as a model for UBe_13
We investigate the mixed-valent regime of a two-configuration Anderson
impurity model for uranium ions, with separate quadrupolar and magnetic
doublets. With a new Monte Carlo approach and the non-crossing approximation we
find: (i) A non-Fermi-liquid fixed point with two-channel Kondo model critical
behavior; (ii) Distinct energy scales for screening the low-lying and excited
doublets; (iii) A semi-quantitative explanation of magnetic-susceptibility data
for UThBe assuming 60-70% quadrupolar doublet ground-state
weight, supporting the quadrupolar-Kondo interpretation.Comment: 4 Pages, 3 eps figures; submitted to Phys. Rev. Let
Interplay of disorder and magnetic field in the superconducting vortex state
We calculate the density of states of an inhomogeneous superconductor in a
magnetic field where the positions of vortices are distributed completely at
random. We consider both the cases of s-wave and d-wave pairing. For both
pairing symmetries either the presence of disorder or increasing the density of
vortices enhances the low energy density of states. In the s-wave case the gap
is filled and the density of states is a power law at low energies. In the
d-wave case the density of states is finite at zero energy and it rises
linearly at very low energies in the Dirac isotropic case
(\alpha_D=t/\Delta_0=1, where t is the hopping integral and \Delta_0 is the
amplitude of the order parameter). For slightly higher energies the density of
states crosses over to a quadratic behavior. As the Dirac anisotropy increases
(as \Delta_0 decreases with respect to the hopping term) the linear region
decreases in width. Neglecting this small region the density of states
interpolates between quadratic and back to linear as \alpha_D increases. The
low energy states are strongly peaked near the vortex cores.Comment: 12 REVTeX pages, 15 figure
Magnetic impurities in a superconductor: Effect of domain walls and interference
We consider the effect of magnetic impurities, modeled by classical spins, in
a conventional superconductor. We study their effect on the quasiparticles,
specifically on the spin density and local density of states (LDOS). As
previously emphasized, the impurities induce multiple scatterings of the
quasiparticle wave functions leading to complex interference phenomena. Also,
the impurities induce quantum phase transitions in the many-body system.
Previous authors studied the effect of either a small number of impurities
(from one to three) or a finite concentration of impurities, typically in a
disordered distribution. In this work we assume a regular set of spins
distributed inside the superconductor in such a way that the spins are
oriented, forming different types of domain walls, assumed stable. This
situation may be particularly interesting in the context of spin transfer due
to polarized currents traversing the material.Comment: 26 pages, 26 figures (72 in total
Quasiparticle spectrum of a type-II superconductor in a high magnetic field with randomly pinned vortices
We show that gapless superconductivity of a strongly type-II superconductor
in a high magnetic field prevails in the presence of disorder, suggesting a
topological nature. We calculate the density of states of the Bogoliubov-de
Gennes quasiparticles for a two-dimensional inhomogeneous system in both cases
of weak and strong disorder. In the limit of very weak disorder, the effect is
very small and the density of states is not appreciably changed. As the
disorder increases, the density of states at low energies increases and the
ratio of the low-energy density of states to its maximum increases
significantly
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