1,720,971 research outputs found
Incremental spare capacity allocation for optical networks restoration
Full text linkFil: Gonzalez-Montoro, Nehuen. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Finochietto, Jorge M. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Survivability of optical networks is
one of the most relevant planning problems due to
its impact on actual deployment cost. Indeed, survivability can only be achieved by deploying spare resources that will only be used under failure scenarios.
In particular, the case of dual link failures on fiber optic cables (i.e., fiber cuts) has recently received much
attention as repairing these cables typically takes too
much time, which increases the probability of a second fiber cut. In this paper, we consider dual link
failure scenarios and analyse the spare capacity allocation problem for restoration schemes, which have
the potential to achieve better survivability performance than protection schemes in non-triconnected
networks. However, since the traditional global optimization approach is not practical for large networks, we propose an incremental optimization approach that can find sub-optimal solutions in practical
times even in large networks.http://ieeexplore.ieee.org/Xplore/home.jspFil: Gonzalez-Montoro, Nehuen. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Finochietto, Jorge M. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Telecomunicacione
Multi-match Packet Classification on Memory-Logic Trade-off FPGA-based Architecture
Full text linkFil: Zerbini, Carlos A. Universidad Tecnológica Nacional. Departamento de Ingeniería Electrónica; Argentina.Fil: Finochietto, Jorge M. Universidad Nacional de Córdoba. Consejo Nacional de Investigaciones Científicas y Técnicas. Laboratorio de Comunicaciones Digitales; Argentina.Packet processing is becoming much more challenging as networks evolve towards a multi-service platform. In particular, packet classification demands smaller processing times as data rates increase. To successfully meet this requirement, hardware-based classification architectures have become an area of extensive research. Even if Field Programmable Logic Arrays (FPGAs) have emerged as an interesting technology for implementing these architectures, existing proposals either exploit maximal concurrency with unbounded resource consumption, or base the architecture on distributed RAM memory-based schemes which strongly undervalues FPGA capabilities. Moreover, most of these proposals target best-match classification and are not suited for high-speed updates of classification rulesets. In this paper, we propose a new approach which exploits rich logic resources available in modern FPGAs while reducing memory consumption. Our architecture is conceived for multi-match classification, and its mapping methodology is naturally suited for high-speed, simple updating of the classification ruleset. Analytical evaluation and implementation results of our architecture are promising, demonstrating that it is suitable for line speed processing with balanced resource consumption. With additional optimizations, our proposal has the potential to be integrated into network processing architectures demanding all aforementioned features.http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6602301Fil: Zerbini, Carlos A. Universidad Tecnológica Nacional. Departamento de Ingeniería Electrónica; Argentina.Fil: Finochietto, Jorge M. Universidad Nacional de Córdoba. Consejo Nacional de Investigaciones Científicas y Técnicas. Laboratorio de Comunicaciones Digitales; Argentina.Ingeniería de Sistemas y Comunicacione
Survivability Analysis on Non-Triconnected Optical Networks under Dual-Link Failures
Full text linkFil: González-Montoro, Nehuén. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina.Fil: Finochietto, Jorge M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina.Survivability of optical networks is considered
among the most critical problems that telecommunications operators need to solve at a reasonable cost. Survivability can be
enhanced by increasing the amount of network links and its
spare capacity, nevertheless this deploys more resources on the
network that will be used only under failure scenarios. In other
words, these spare resources do not generate any direct profit to
network operators as they are reserved to route only disrupted
traffic. In particular, the case of dual link failures on fiber optic
cables (i.e., fiber cuts) has recently received much attention as
repairing these cables typically requires much time, which then
increases the probability of a second failure on another link of
the network. In this context, survivability schemes can be used
to recover the network from a dual link failure scenario. In this
work, we analyze the case of protection and restoration schemes,
which are two well-known recovery strategies. The former is
simpler to implement as it considers a fixed set of backup paths
for all failure scenarios; however, it cannot take into account
the spare capacity released by disrupted connections. Instead,
the latter computes the best recovery path considering not only
the spare capacity but also the released one due to failures.
Achieving 100% survivability (i.e., recovery from all possible
dual link failures) requires a triconnected network, where three
disjoint paths for each connection are required. Since these
networks can become extremely expensive since they can require
a huge number of network links (i.e., fibers connections), a more
realistic case of non-triconnected networks is assumed. In these
networks, full network recovery is not be feasible, but achieving
the maximum possible survivability is desired. Spare capacity can
then be allocated to existing network links, which represents the
actual cost of the survivability. We propose optimization models
that take into account these different recovery strategies, and
demonstrate that restoration has the potential to provide a much
better recovery capability with almost the same amount of spare
capacity required in protection schemes.https://ieeexplore.ieee.org/document/8226411/Fil: González-Montoro, Nehuén. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina.Fil: Finochietto, Jorge M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en Ingeniería y Tecnología; Argentina.Telecomunicacione
Translucent Provisioning in Elastic Optical Networks with Sliceable Bandwidth Variable Transponders
No full textElastic Optical Networks (EONs) permit a trade-off between spectrum and regeneration use. Provisioning strategies for translucent EONs can reduce spectrum requirements at the cost of additional Bandwidth Variable Transponders (BVTs) used for regeneration. In this context, Sliceable Bandwidth Variable Transponders (SBVTs) can enable transponder sharing among multiple demands, potentially reducing regeneration costs. In this paper, we analyze the impact of SBVTs on the translucent provisioning process of EONs. In particular, we demonstrate that the use of SBVTs can improve blocking probability at almost no extra cost. We discuss simulation results for dynamic traffic over an EON when using different provisioning strategies that use SBVTs with respect to BVTs. Results reflect that the translucent strategy can significantly reduce the blocking probability even without the need of extra transponder deploymen
Optimal Provisioning Strategies for Translucent Elastic Optical Networks
No full textProvisioning strategies for Translucent Elastic Optical Networks (EONs) should consider both spectrum and transponder costs. End-to-end connections that support user demands may be obtained on the one hand via transparent paths, which avoid regeneration costs but may require more spectrum slot, thus increasing the blocking probability, on the other hand via opaque paths that can reduce spectrum requirements, but at the cost of additional transponders for regeneration purposes. In this context, a wise provisioning strategy needs to consider translucent paths that can provide a good trade-off between transparent and opaque solutions. We propose a provisioning strategy that considers a multi-objective optimization problem aiming at the joint minimization of spectrum resources and regenerators. We show that the proposed strategy can significantly reduce regeneration costs while achieving low blocking probability
COVID‑19 mitigation by digital contact tracing and contact prevention (app‑based social exposure warnings)
Full text linkFil: Soldano, Germán J. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Soldano, Germán J. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina.Fil: Fraire Juan A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Fraire Juan A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en ingeniería y Tecnología; Argentina.Fil: Fraire Juan A. Saarland University. Saarland Informatics Campus; Saarbrücken, Germany.Fil: Finochietto, Jorge M. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Finochietto, Jorge M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en ingeniería y Tecnología; Argentina.Fil: Quiroga; Rodrigo. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Quiroga; Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina.A plethora of measures are being combined in the attempt to reduce SARS-CoV-2 spread. Due to its sustainability, contact tracing is one of the most frequently applied interventions worldwide, albeit with mixed results. We evaluate the performance of digital contact tracing for different infection detection rates and response time delays. We also introduce and analyze a novel strategy we call contact prevention, which emits high exposure warnings to smartphone users according to Bluetooth-based contact counting. We model the effect of both strategies on transmission dynamics in SERIA, an agent-based simulation platform that implements population-dependent statistical distributions. Results show that contact prevention remains effective in scenarios with high diagnostic/response time delays and low infection detection rates, which greatly impair the effect of traditional contact tracing strategies. Contact prevention could play a significant role in pandemic mitigation, especially in developing countries where diagnostic and tracing capabilities are inadequate. Contact prevention could thus sustainably reduce the propagation of respiratory viruses while relying on available technology, respecting data privacy, and most importantly, promoting community-based awareness and social responsibility. Depending on infection detection and app adoption rates, applying a combination of digital contact tracing and contact prevention could reduce pandemic-related mortality by 20–56%.publishedVersionFil: Soldano, Germán J. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Soldano, Germán J. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina.Fil: Fraire Juan A. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Fraire Juan A. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en ingeniería y Tecnología; Argentina.Fil: Fraire Juan A. Saarland University. Saarland Informatics Campus; Saarbrücken, Germany.Fil: Finochietto, Jorge M. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Finochietto, Jorge M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Estudios Avanzados en ingeniería y Tecnología; Argentina.Fil: Quiroga; Rodrigo. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas; Argentina.Fil: Quiroga; Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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