3,322 research outputs found
Electromagnetic topology: Characterization of internal electromagnetic coupling
The main principles are presented of a method dealing with the resolution of electromagnetic internal problems: Electromagnetic Topology. A very interesting way is to generalize the multiconductor transmission line network theory to the basic equation of the Electromagnetic Topology: the BLT equation. This generalization is illustrated by the treatment of an aperture as a four port junction. Analytical and experimental derivations of the scattering parameters are presented. These concepts are used to study the electromagnetic coupling in a scale model of an aircraft, and can be seen as a convenient means to test internal electromagnetic interference
Nuevo grillo (Orthoptera, Gryllidae) para Castilla-La Mancha y la penÃnsula Ibérica
We report Tartarogryllus tartarus (Saussure, 1874), a species with disjunct distribution in the Mediterranean-Turanean area, for the first time in the Iberian Peninsula. We summarize morphological charateristics for the species identification adding some new relevant traits to distinguish it from Acheta domesticus and Eumodicogryllus bordigalensis, particularly the interior tympanic opening that is shaped like a narrow slot whereas it is almost rounded in Acheta and Eumodicogryllus. We have found the species in cereal crops and vegetation around hiper-saline lagoons of arid lands (Castilla-La Mancha, Spain). Adult emergence occurs in May with maximum sexual activity at the end of this month and in June. We suspect that this species may be more widely distributed in other regions of the Iberian Peninsula with appropriate habitat.Encontramos por primera vez en la penÃnsula Ibérica Tartarogryllus tartarus (Saussure, 1874), especie de distribución disjunta en el área Turano-Mediterránea. Resumimos los distintos caracteres morfológicos utilizados para identificar esta especie y añadimos algunos nuevos para distinguirla de especies similares como Acheta domesticus y Eumodicogryllus bordigalensis. Destacamos la apertura timpánica interior en forma de ranura estrecha y poco perceptible en esta especie mientras que es redondeada en Acheta y en Eumodicogryllus. Habita cultivos de cereal y vegetación en zonas áridas alrededor de lagunas hipersalinas (Castilla-La Mancha, España). Los adultos emergen a partir de mediados de mayo con máxima actividad reproductiva a finales de este mes y en junio. Sugerimos que la especie puede tener una distribución más amplia en la penÃnsula Ibérica en aquellas regiones que presentan el hábitat adecuado
Patient Health Portal: user calendar perspective
In this paper, we do a brief literature review on portals and their stakeholders. Health portal stakeholders are identified, within their internal and external action to the system. It is also reported the results of an analysis made to a number of European, United States and Australia health portals. In this paper we propose a conceptual model of a patient health portal based on a calendar perspective. Users’ needs are reflected in this conceptual model. We also describe the implementation of prototype based on the conceptual model. The prototype was built in an open source content management system (Drupal). Our study does also include a statistical analysis of the preliminary results of a survey to a group of users
Passive cooling applicability mapping: A tool for designers
The applicability of passive cooling methods has been a recurring subject in architectural engineering science. The integration of these methods in architecture often requires feasibility studies and, in most cases, a deep knowledge of the climatic conditions is required to succeed in this task. The number of parameters to be evaluated will depend on the complexity of the cooling system, the physics involved and the context. This paper addresses the climatic applicability of convective and evaporative cooling systems in the context of United States (US) through the creation of a series of applicability maps deriving from processed climate data. This work is a revision of the climatic maps for downdraught cooling developed in Europe and in China with an extension to evaluate the opportunity for natural ventilation. More specifically, the studied cooling solutions are: Natural Convective Cooling (NCC), Passive Evaporative Cooling (PEC), and Active Downdraught Cooling (ADC). The maps obtained demonstrate the strong potential for the use of passive evaporative and convective cooling solutions in the US to overcome the current dependency on mechanical systems
Blockchain technology in the auditing environment
Blockchain technology is already being talked about as one of the megatrends for the next years. Researchers and organisations are starting to understand the potential benefits of this technology and are exploring how it can disrupt the world we live in with a diverse range of applications. But the truth is the ability to move blockchain from concept to adoption and production has been minimal yet. When it comes to auditing, blockchain solutions could have important benefits by reducing the workload of the auditors, helping in minimising fraud and optimising the existing processes but is also vital to have in mind other emerging technologies. Factom, Libra, and Verady are some examples of companies developing blockchain solutions that can be applied in the auditing environment, but much of the necessary development is still yet to be done.info:eu-repo/semantics/acceptedVersio
The spatial and age distribution of stellar populations in DDO 190
The spatial distribution of stellar populations, the star formation history,
and other properties of the dIrr galaxy DDO 190 have been analyzed using
color--magnitude diagrams (CMDs) of about 3900 resolved stars and the Ha fluxes
of HII regions. From the mean color index of the red giant branch, a mean
metallicity [Fe/H]=-2.0 is obtained. The I magnitude of the TRGB has been used
to estimate the distance. DDO 190 is 2.9+/-0.2 Mpc from the Milky Way, 2.1 Mpc
from the M 94 group (CnV-I), 2.4 Mpc from the M 81 group and 2.9 Mpc from the
barycenter of the Local Group, all indicating that it is an isolated, field
galaxy. The surface-brightness distribution of the galaxy is well fitted by
ellipses of ellipticity e=1-a/b=0.1 and P.A.=82deg. The radial star density
distribution follows an exponential law of scale length a=43."4, corresponding
to 611 pc. The Holmberg semi-major axis to mu_B=26.5 is estimated to be
r^B_(26.5)=3.'0. Stellar populations of different ages in DDO 190 show strong
spatial decoupling, the oldest population appearing much more extended than the
youngest. Stars younger than 0.1 Gyr occupy only the central 40'' (0.55 kpc);
stars younger than a few (~4) Gyr extend out to ~80'' (125 kpc), and for larger
galactocentric distances only older stars seem to be present. This behavior is
found in all the dIrr galaxies for which spatially extended studies have been
performed and could be related with the kinematical history of the galaxy.Comment: To be published in the AJ. 29 pages, 13 figure
Rotation of Hot Horizontal Branch Stars in the Globular Clusters NGC 1904, NGC 2808, NGC 6093 and NGC 7078
We present high resolution UVES+VLT spectroscopic observations of 56 stars in
the extended horizontal branch (EHB) of the Galactic globular clusters NGC
1904, NGC 2808, NGC 6093, and NGC 7078. Our data reveal for the first time the
presence in NGC 1904 of a sizable population of fast (vsini > 20 km/s)
horizontal branch (HB) rotators, confined to the cool end of the EHB, similar
to that found in M13. We also confirm the fast rotators already observed in NGC
7078. The cooler stars (Teff < 11,500 K) in these three clusters show a range
of rotation rates, with a group of stars rotating at ~ 15 km/s or less, and a
fast rotating group at ~ 30 km/s. Apparently, the fast rotators are relatively
more abundant in NGC 1904 and M13, than in NGC 7078. No fast rotators have been
identified in NGC 2808 and NGC 6093. All the stars hotter than Teff ~ 11,500 K
have projected rotational velocities vsini < 12 km/s, but less than 20% have
vsini < 2 km/s. The connection between photometric gaps in the HB and the
change in the projected rotational velocities is not confirmed by the new data.
However, our data are consistent with a relation between this discontinuity and
the HB jump. We discuss a number of possibilities for the origin of the stellar
rotation distribution along the HB. We conclude that none of them can yet
provide a satisfactory explanation of the observations.Comment: 12 pages, 3 figures, ApJ Letter, accepte
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