5,402 research outputs found
Fan blade protection system
In one type of aircraft propulsion system, propeller blades are mounted on a ring which surrounds a turbine. An annular space exists between the turbine and the ring. If a propeller blade should break free, the unbalanced centrifugal load tends to deform the ring. The invention reduces the deformation, as by locating spacers between the turbine and the ring
Enhancement of bulk second-harmonic generation from silicon nitride films by material composition
We present a comprehensive tensorial characterization of second-harmonic
generation from silicon nitride films with varying composition. The samples
were fabricated using plasma-enhanced chemical vapor deposition, and the
material composition was varied by the reactive gas mixture in the process. We
found a six-fold enhancement between the lowest and highest second-order
susceptibility, with the highest value of approximately 5 pm/V from the most
silicon-rich sample. Moreover, the optical losses were found to be sufficiently
small (below 6 dB/cm) for applications. The tensorial results show that all
samples retain in-plane isotropy independent of silicon content, highlighting
the controllability of the fabrication process.Comment: 4 pages, 3 figures, 2 tables; Re-submitted to Optics Letter
Dialogical self strategies of self-organization: psychotherapy and restructuring of internal management
A identidade tem sido um conceito central na literatura em psicologia e na forma como as diferentes abordagens terapêuticas têm concebido os processos de mudança. Entre as inúmeras perspectivas desenvolvidas sobre essa dimensão do ser humano, destacamos o paradigma dialógico que tem vindo a influenciar de forma crescente a teoria e prática em psicoterapia. Segundo esta perspectiva, a funcionalidade psicológica está relacionada com o modo como os indivíduos conseguem articular e colocar em diálogo produtivo as suas várias vozes ou posições de identidade. Neste artigo apresentamos uma revisão da literatura sobre as estratégias que subjazem a essa capacidade auto-organizadora do sistema identitário e sobre as diretrizes que poderão orientar uma intervenção terapêutica dialógica quando essa capacidade se torna disfuncional.Self-concept has been playing a crucial role in psychological literature and in the way the different therapeutic approaches conceive the processes of change. From the diverse perspectives developed about this human dimension, we emphasise the dialogical paradigm that has been increasingly influential in the psychotherapeutic theory and practice. According to the dialogical perspective the psychological well-being is dependent on the way individuals articulate and maintain productive dialogues between the different voices of the self or “I-Positions”. In this paper we present a review of the literature on the strategies that underlie this self-regulatory ability of the self-system and the guidelines of the dialogical therapeutic intervention that could be used when these self-regulatory strategies become dysfunctional.(undefined
Olfactomedin 4 Serves as a Marker for Disease Severity in Pediatric Respiratory Syncytial Virus (RSV) Infection
Funding: Statement of financial support: The study was financially supported by the VIRGO consortium, an Innovative Cluster approved by the Netherlands Genomics Initiative and partially funded by the Dutch Government (BSIK 03012). The authors have indicated they have no personal financial relationships relevant to this article to disclose. Data Availability Statement: The data is accessible at http://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE69606.Peer reviewedPublisher PD
Grasping the dialogical nature of acculturation
In this interesting article, Andreouli (2013). Identity and acculturation: The case of
naturalised citizens in Britain. Culture & Psychology, 19, 1–47) presents a dialogical perspective
on acculturation. To support this perspective, the author integrates the
Dialogical Self Theory and the Social Representations Theory. Drawing on her theoretical
explanation, we develop a conceptual review focused on two pairs of constructs –
social representations/I-positions and polyphasia/polyphonia. Andreouli’s empirical
study allowed her to operationalize some critiques about the two-dimensional perspective
and its strategies on acculturation. Nevertheless, it seems that the author ends up
replicating a more conventional and dual way of thinking. Their results give us privileged
access to the negotiation of meanings and activation of promoter signs or, in other
words, to the dialogical dynamics between I-positions. In this respect, we suggest that
the assumption of a more dialogic and semiotic lens could be an interesting further
development to this study
Learning robot in-hand manipulation with tactile features
Dexterous manipulation enables repositioning of
objects and tools within a robot’s hand. When applying dexterous
manipulation to unknown objects, exact object models
are not available. Instead of relying on models, compliance and
tactile feedback can be exploited to adapt to unknown objects.
However, compliant hands and tactile sensors add complexity
and are themselves difficult to model. Hence, we propose acquiring
in-hand manipulation skills through reinforcement learning,
which does not require analytic dynamics or kinematics models.
In this paper, we show that this approach successfully acquires
a tactile manipulation skill using a passively compliant hand.
Additionally, we show that the learned tactile skill generalizes
to novel objects
Probability distributions of the work in the 2D-Ising model
Probability distributions of the magnetic work are computed for the 2D Ising
model by means of Monte Carlo simulations. The system is first prepared at
equilibrium for three temperatures below, at and above the critical point. A
magnetic field is then applied and grown linearly at different rates.
Probability distributions of the work are stored and free energy differences
computed using the Jarzynski equality. Consistency is checked and the dynamics
of the system is analyzed. Free energies and dissipated works are reproduced
with simple models. The critical exponent is estimated in an usual
manner.Comment: 12 pages, 6 figures. Comments are welcom
Reservoir Computing Approach to Robust Computation using Unreliable Nanoscale Networks
As we approach the physical limits of CMOS technology, advances in materials
science and nanotechnology are making available a variety of unconventional
computing substrates that can potentially replace top-down-designed
silicon-based computing devices. Inherent stochasticity in the fabrication
process and nanometer scale of these substrates inevitably lead to design
variations, defects, faults, and noise in the resulting devices. A key
challenge is how to harness such devices to perform robust computation. We
propose reservoir computing as a solution. In reservoir computing, computation
takes place by translating the dynamics of an excited medium, called a
reservoir, into a desired output. This approach eliminates the need for
external control and redundancy, and the programming is done using a
closed-form regression problem on the output, which also allows concurrent
programming using a single device. Using a theoretical model, we show that both
regular and irregular reservoirs are intrinsically robust to structural noise
as they perform computation
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