5,131 research outputs found
The Agendas 21 of the Cordoba province. The identification of sustainability indicators, their diffusion and their impact on decision making
En la provincia de Córdoba se está consolidando la implantación de Agendas 21 tanto en lo que respecta a las Agendas 21 Locales como a la Agenda 21 Provincial. Una vez superadas las etapas iniciales, en la cuales se sientan las bases del proceso y se desarrolla la planificación estrategia hacia la sostenibilidad, resulta necesario plantear la puesta en valor de los logros alcanzados, sobre todo considerando la explotación de los indicadores de sostenibilidad ya determinadosIn the Cordoba province is consolidating the implenentation of Agenda 21 as in regard to Local Agenda 21 as to the Provincial. Once you get past the initial stages, in which the foundations of the process and develop the planning strategy towards sustainability, it is necessary to consider
the enhancement of the achievements, above all considering the use of sustainability indicators already certainPeer Reviewe
Dataplane Specialization for High-performance OpenFlow Software Switching
OpenFlow is an amazingly expressive dataplane program-
ming language, but this expressiveness comes at a severe
performance price as switches must do excessive packet clas-
sification in the fast path. The prevalent OpenFlow software
switch architecture is therefore built on flow caching, but
this imposes intricate limitations on the workloads that can
be supported efficiently and may even open the door to mali-
cious cache overflow attacks. In this paper we argue that in-
stead of enforcing the same universal flow cache semantics
to all OpenFlow applications and optimize for the common
case, a switch should rather automatically specialize its dat-
aplane piecemeal with respect to the configured workload.
We introduce ES WITCH , a novel switch architecture that
uses on-the-fly template-based code generation to compile
any OpenFlow pipeline into efficient machine code, which
can then be readily used as fast path. We present a proof-
of-concept prototype and we demonstrate on illustrative use
cases that ES WITCH yields a simpler architecture, superior
packet processing speed, improved latency and CPU scala-
bility, and predictable performance. Our prototype can eas-
ily scale beyond 100 Gbps on a single Intel blade even with
complex OpenFlow pipelines
Vacuum fluctuations and the conditional homodyne detection of squeezed light
Conditional homodyne detection of quadrature squeezing is compared with
standard nonconditional detection. Whereas the latter identifies
nonclassicality in a quantitative way, as a reduction of the noise power below
the shot noise level, conditional detection makes a qualitative distinction
between vacuum state squeezing and squeezed classical noise. Implications of
this comparison for the realistic interpretation of vacuum fluctuations
(stochastic electrodynamics) are discussed.Comment: 14 pages, 7 figures, to appear in J. Opt. B: Quantum Semiclass. Op
The primitive model of ionic fluids near its critical point in the Poisson–Boltzmann and modified Poisson–Boltzmann theories
The Poisson–Boltzmann (PB) and modified Poisson–Boltzmann (MPB) theories are used to investigate the primitive model of ionic fluids in the low density–large coupling regime where the liquid–vapor transition is situated. The PB and MPB spinodal curves for the restricted primitive model are calculated from the virial route and compared with those from the mean spherical approximation (energy route) and the hybrid hypernetted‐chain/mean spherical approximation (virial route). The effect of unequal ion sizes on the critical point and spinodal curves is also considered.National Sanitation Foundation (NSF) EE.UU. CHE-8907130Fondo Institucional para la Investigación (FIPI) de la Universidad de Puerto RicoComunidad Europea (beca Marie Curie)Dirección General de Investigación Científica y Técnica (DGICYT). España PBgl / 060
Protein interaction perturbation profiling at amino-acid resolution
The identification of genomic variants in healthy and diseased individuals continues to rapidly outpace our ability to functionally annotate these variants. Techniques that both systematically assay the functional consequences of nucleotide-resolution variation and can scale to hundreds of genes are urgently required. We designed a sensitive yeast two-hybrid-based 'off switch' for positive selection of interaction-disruptive variants from complex genetic libraries. Combined with massively parallel programmed mutagenesis and a sequencing readout, this method enables systematic profiling of protein-interaction determinants at amino-acid resolution. We defined >1,000 interaction-disrupting amino acid mutations across eight subunits of the BBSome, the major human cilia protein complex associated with the pleiotropic genetic disorder Bardet–Biedl syndrome. These high-resolution interaction-perturbation profiles provide a framework for interpreting patient-derived mutations across the entire protein complex and thus highlight how the impact of disease variation on interactome networks can be systematically assessed
Las Agendas 21 de la provincia de Córdoba. La determinación de indicadores de sostenibilidad, su difusión y su incidencia sobre la toma de decisiones
In the Cordoba province is consolidating the implenentation of Agenda 21 as in regard to Local Agenda 21 as to the Provincial. Once you get past the initial stages, in which the foundations of the process and develop the planning strategy towards sustainability, it is necessary to consider
the enhancement of the achievements, above all considering the use of sustainability indicators already certai
Gain in Stochastic Resonance: Precise Numerics versus Linear Response Theory beyond the Two-Mode Approximation
In the context of the phenomenon of Stochastic Resonance (SR) we study the
correlation function, the signal-to-noise ratio (SNR) and the ratio of output
over input SNR, i.e. the gain, which is associated to the nonlinear response of
a bistable system driven by time-periodic forces and white Gaussian noise.
These quantifiers for SR are evaluated using the techniques of Linear Response
Theory (LRT) beyond the usually employed two-mode approximation scheme. We
analytically demonstrate within such an extended LRT description that the gain
can indeed not exceed unity. We implement an efficient algorithm, based on work
by Greenside and Helfand (detailed in the Appendix), to integrate the driven
Langevin equation over a wide range of parameter values. The predictions of LRT
are carefully tested against the results obtained from numerical solutions of
the corresponding Langevin equation over a wide range of parameter values. We
further present an accurate procedure to evaluate the distinct contributions of
the coherent and incoherent parts of the correlation function to the SNR and
the gain. As a main result we show for subthreshold driving that both, the
correlation function and the SNR can deviate substantially from the predictions
of LRT and yet, the gain can be either larger or smaller than unity. In
particular, we find that the gain can exceed unity in the strongly nonlinear
regime which is characterized by weak noise and very slow multifrequency
subthreshold input signals with a small duty cycle. This latter result is in
agreement with recent analogue simulation results by Gingl et al. in Refs. [18,
19].Comment: 22 pages, 5 eps figures, submitted to PR
Coherent Signal Amplification in Bistable Nanomechanical Oscillators by Stochastic Resonance
Stochastic resonance is a counter-intuitive concept[1,2], ; the addition of
noise to a noisy system induces coherent amplification of its response. First
suggested as a mechanism for the cyclic recurrence of ice ages, stochastic
resonance has been seen in a wide variety of macroscopic physical systems:
bistable ring lasers[3], SQUIDs[4,5], magnetoelastic ribbons[6], and
neurophysiological systems such as the receptors in crickets[7] and
crayfish[8]. Although it is fundamentally important as a mechanism of coherent
signal amplification, stochastic resonance is yet to be observed in nanoscale
systems. Here we report the observation of stochastic resonance in bistable
nanomechanical silicon oscillators, which can play an important role in the
realization of controllable high-speed nanomechanical memory cells. Our
nanomechanical systems were excited into a dynamic bistable state and modulated
in order to induce controllable switching; the addition of white noise showed a
marked amplification of the signal strength. Stochastic resonance in
nanomechanical systems paves the way for exploring macroscopic quantum
coherence and tunneling, and controlling nanoscale quantum systems for their
eventual use as robust quantum logic devices.Comment: 18 pages, 4 figure
Industry-specific effect of CSR initiatives: hotels and airlines
Purpose – This study aims to examine the relationships between a firm's corporate social responsibility (CSR) activities and its performance and risk. The authors hypothesize that industry-level effects are highly determinant of the sign and magnitude of these relationships to establish a ranking of industries to identify the position of the most prominent tourism-related industries: hotels and airlines. Based on the cybernetic model of decision making and the heuristics thereof, shareholders base their investment decisions derived from CSR announcements on the idea that the industries behave differently; their fixed costs being a relevant factor. Design/methodology/approach – The authors estimate the industry-specific effects of CSR initiatives on firms' performance and risk using a sample of 583 announcements from the Spanish Stock Market. Findings – The results show that while CSR announcements have a positive effect on performance when the authors do not account for industry-specific factors, once the authors incorporate these factors into the analysis, the authors find that firm performance and risk vary quite substantially as a function of the industry to which the firm belongs. Interestingly, while the hotel industry presents an average behavior (standing at 9th position in returns, 15th in terms of risk, and 8th according to the ratio returns/volatility), the airline industry presents the worst situation of all industries: last in performance and last in risk. Practical implications – The results help managers assess their decisions and allocate CSR resources optimally. Originality/value – This article is the first attempt to empirically test and comprehensively detect the different relationships between CSR and firm performance across industries.The authors gratefully acknowledge the financial support (ECO0805487) provided by the Spanish Ministerio de Ciencia e Innovación
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