4,123 research outputs found
On the generalized Nash problem for smooth germs and adjacencies of curve singularities
In this paper we explore the generalized Nash problem for arcs on a germ of
smooth surface: given two prime divisors above its special point, to determine
whether the arc space of one of them is included in the arc space of the other
one. We prove that this problem is combinatorial and we explore its relation
with several notions of adjacency of plane curve singularities.Comment: Final versio
Routing cost optimization in Multi Overlay Robust Networks
In the present work we solve the problem of data flow routing in Multi-Overlay Robust
Networks (MORN) while aiming to minimize its routing cost. This kind of networks are typically
IP/MPLS Data Network deployed over an SDH/DWDM transport infrastructure.
Through the IP/MPLSMulti-Layer Data Network different kinds of services having a wide
variety of quality of service requirements are delivered. Those services are being transported by
an SDH/DWDM Transport Network which has different transport capacities. In this network,
routing cost depends not only on the assigned transport capacity but also in the technology that
it uses.
Our problem seeks not only to route data flows through Data and Transport Networks but
also to optimize routing costs and the reliability of the network. The inputs of our problem
are the topology of the Data and Transport networks as well as the budget that the network
operator has in order to improve its network routing costs and reliability. We will assume that
the operator can only use that budget for installing new links between existing transport nodes.
The output of the problem is the data flow routing in the Data and Transport Networks and
its associated cost. Routing in the Transport Network is calculated not only in the nominal
scenario - when all the Transport Network links are up and running - but also in each single
transport link failure case.En el presente trabajo se resuelve el problema de rutear flujos de datos en una Red Multi-
Capa Robusta (MORN por sus siglas en inglés), mientras que se trata de minimizar el costo
asociado a su ruteo. Este tipo de redes son generalmente redes de datos IP/MPLS desplegadas
sobre una infraestructura de transporte SDH/DWDM.
Sobre la red de datos IP/MPLS se cursan distintos servicios con diferentes requerimientos
de calidad de servicio (QoS). Los servicios de la Red de Datos son transportados por la red
SDH/DWDM la cual tiene distintas capacidades de transporte. En éste tipo de redes el costo
asociado al transporte depende no solo de la capacidad asignada para el transporte sino que
también depende de la tecncología utilizada para transportar dicha capacidad.
En el problema no sólo se busca enrutar flujos de datos a través de las Redes de Datos y
Transporte sino que también se busca optimizar los costos de ruteo y la confiabilidad de la red.
Como punto de partida, el problema toma como información la topología de las Redes de Datos
y Transporte así como cierto presupuesto que el operador de la red posee para poder mejorar
los costos de ruteo y la confiabilidad de su red. Asumiremos que dicho presupuesto solo puede
ser utilizado para instalar nuevos enlaces entre los nodos existentes en la Red de Transporte.
La salida del problema es el ruteo de los flujos de datos tanto en la Red de Datos como en la
de Transporte, así como el costo asociado a dicho ruteo. El ruteo en la Red de Transporte se
calcula no solo en el escenario nominal - cuando todos los enlaces de la Red de Transporte
están funcionales - sino que también en cada escenario de falla simple en sus enlaces
Towards the development of the supply chain of concentrated solar power
This work focuses on the investigation into the planning of renewable energy power plants in Brazil using the Concentrated Solar Power (CSP) technology. The main aim of the paper is to present an analysis of the planning process that can be used as a basis of the development of a method to assess the Brazilian’s local manufacturing and supply chain capabilities in supporting the deployment of the CSP technology. The paper identifies areas in which the concerted efforts should be emphasized. For this, the paper will first discuss the key components of the chosen CSP technology (in this case the parabolic through). The manufacturing processes of these components will subsequently be analyzed and the key enabling technologies will be determined. The demands of electricity will be estimated using the System Advisory Model®, a modelling tool developed by the National Renewable Energy Laboratory (NREL). An assessment method will finally be proposed to identify the potentials of the local Brazilian supply chain, through the readiness evaluation of the key enabling technologies and manufacturing processes
Warm molecular gas temperature distribution in six local infrared bright Seyfert galaxies
We simultaneously analyze the spectral line energy distributions (SLEDs) of
CO and H2 of six local luminous infrared (IR) Seyfert galaxies. For the CO
SLEDs, we used new Herschel/SPIRE FTS data (from J=4-3 to J=13-12) and
ground-based observations for the lower-J CO transitions. The H2 SLEDs were
constructed using archival mid-IR Spitzer/IRS and near-IR VLT/SINFONI data for
the rotational and ro-vibrational H2 transitions, respectively. In total, the
SLEDs contain 26 transitions with upper level energies between 5 and 15000 K. A
single, constant density, model (n ~ 10 cm) with a
broken power-law temperature distribution reproduces well both the CO and H2
SLEDs. The power-law indices are ~ 1-3 for warm molecular gas (20 K <
T 100 K). We show that
the steeper temperature distribution (higher ) for hot molecular gas can
be explained by shocks and photodissociation region (PDR) models, however, the
exact values are not reproduced by PDR or shock models alone and a
combination of both is needed. We find that the three major mergers among our
targets have shallower temperature distributions for warm molecular gas than
the other three spiral galaxies. This can be explained by a higher relative
contribution of shock excitation, with respect to PDR excitation, for the warm
molecular gas in these mergers. For only one of the mergers, IRASF 05189-2524,
the shallower H2 temperature distribution differs from that of the spiral
galaxies. The presence of a bright active galactic nucleus in this source might
explain the warmer molecular gas observed.Comment: A&A in press; 15 pages, 7 figures. Fixed several typo
An overview of seismic strengthening techniques traditionally applied in vernacular architecture
Specific architectural elements can be identified in vernacular constructions located in regions frequently exposed to earthquakes. Such elements are the result of a seismic culture which has been empirically developed during centuries so that the vulnerability of the buildings is reduced. This research is based on the fact that vernacular architecture may bear important lessons on hazard mitigation. Traditional earthquake resistant technologies can be successfully applied to preserve and retrofit surviving examples without prejudice for its identity. Few papers have focused on strengthening solutions emerging from vernacular architectural heritage. Research is particularly focused on case studies in Portugal where traces of Local Seismic Culture have been identified and documented through direct visual inspection, published information and local narratives. The main goal of this study is the identification and understanding of traditional construction solutions and detailing that, in many cases, have shown to improve the seismic performance of vernacular constructions.Fundação para a Ciência e a Tecnologia (FCT
Exposure to selected pathogens in Geoffroy's cats and domestic carnivores from central Argentina
Wild carnivores share a high percentage of parasites and viruses with closely related domestic carnivores. Because of increased overlap and potential contact with domestic species, we conducted a retrospective serosurvey for 11 common carnivore pathogens in 40 Geoffroy's cats (Leopardus geoffroyi) sampled between 2000 and 2008 within or near two protected areas in central Argentina (Lihué Calel National Park, La Pampa, and Campos del Tuyú National Park, Buenos Aires), as well as five domestic cats and 11 domestic dogs from cattle ranches adjacent to Lihué Calel Park. Geoffroy's cats had detectable antibody to canine distemper virus (CDV), feline calicivirus (FCV), feline coronavirus, feline panleukopenia virus (FPV), Toxoplasma gondii, Leptospira interrogans (serovars Ictero/Icter and Ballum), and Dirofilaria immitis. None of the wild cats had antibodies to feline herpesvirus, feline immunodeficiency virus (FIV), feline leukemia virus, or rabies virus. Domestic dogs had antibodies to CDV, canine adenovirus, canine herpesvirus, and canine parvovirus. Antibodies to FPV, FCV, FIV, and T. gondii were found in domestic cats.We provide the first data on exposure of free-ranging Geoffroy's cats to pathogens at two sites within the core area of the species distribution range, including the first report of antibodies to CDV in this species. We encourage continued monitoring for diseases in wild and domestic carnivores as well as preventive health care for domestic animals, particularly in park buffer zones where overlap is greatest.Fil: Uhart, Marcela María. ildlife Conservation Society; ArgentinaFil: Rago, María Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Ecología, Genética y Evolución de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Ecología, Genética y Evolución de Buenos Aires; ArgentinaFil: Marull, Carolina A.. ildlife Conservation Society; ArgentinaFil: Ferreyra, Hebe del Valle. ildlife Conservation Society; ArgentinaFil: Pereira, Javier Adolfo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales “Bernardino Rivadavia”; Argentin
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