2,123 research outputs found
Methods for High Power EM Pulse Measurement
There are some suitable methods for the measurement of ultra-short solitary electromagnetic pulses that can be generated by high power pulsed generators. The measurement methods properties have to correspond to the fact whether we want to measure pulses of voltage, current or free-space electromagnetic wave. The need for specific measurement methods occurred by the development of high power microwave pulse generator. Applicable methods are presented in this paper. The method utilizing Faraday\'s induction law allows the measurement of generated current. For the same purpose the magneto-optic method can be utilized, with its advantages. For measurement of output microwave pulse of the generator the calorimetric method was designed and realized
Constitutional Law - Judicial Power - Court Funding - Reasonable Necessity
The Supreme Court of Pennsylvania held that a survey of salaries offered by competing employers was insufficient evidence of the necessity to increase the salaries of court employees.
Snyder v. Snyder, 620 A.2d 1133 (Pa. 1993)
A possible origin for large aspect angle "HAIR'' echoes seen by SuperDARN radars in the E region
International audienceMilan2004 have recently reported on close-range E region decameter size echoes that seem to be relatively weak, have apparently unusually large aspect angles, and possess Doppler shifts that are slow and are clearly consistent with the ion drift of the medium as opposed to, say, its electron drift or its ion-acoustic speed. We argue that these irregularities are the result of a nonlinear wave conversion process triggered by the nonlocal evolution of decameter Farley-Buneman waves. According to this picture, structures which have weak spontaneous growth rates and are initially field-aligned undergo an evolution of their aspect angle that results in a jump in the aspect angle at some point in time and space. When this takes place, a rapid mode conversion must follow, which takes energy away from a standard two-stream signature and converts it either to a strongly damped ion-acoustic mode or to a purely decaying mode, depending on altitude
High Quality, Transferable Graphene Grown on Single Crystal Cu(111) Thin Films on Basal-Plane Sapphire
The current method of growing large-area graphene on Cu surfaces
(polycrystalline foils and thin films) and its transfer to arbitrary substrates
is technologically attractive. However, the quality of graphene can be improved
significantly by growing it on single-crystal Cu surfaces. Here we show that
high quality, large-area graphene can be grown on epitaxial single-crystal
Cu(111) thin films on reusable basal-plane sapphire (alpha-Al2O3(0001))
substrates and then transferred to another substrate. While enabling graphene
growth on Cu single-crystal surfaces, this method has the potential to avoid
the high cost and extensive damage to graphene associated with sacrificing bulk
single-crystal Cu during graphene transfer.Comment: 10 pages, 3 figure
Reconfigurable antenna pattern verification
A method of verifying programmable antenna configurations is disclosed. The method comprises selecting a desired antenna configuration from a plurality of antenna configuration patterns, with the selected antenna configuration forming at least one reconfigurable antenna from reconfigurable antenna array elements. The method validates the formation of the selected antenna configuration to determine antenna performance of the at least one reconfigurable antenna
La representación del sujeto lírico en "Capitán es el viento", de Raúl Hernández Novás
Fil: Drexler, Carolina P. Universidad Nacional de Río Negro; ArgentinaLa comprensión integral de la obra de Raúl Hernández Novás, deuda pendiente de la crítica literaria, debe, ineludiblemente, de-dicar un profundo análisis a las formas de construcción del sujeto lírico en sus poemas y a la relación que se establece entre esta voz y la del autor material de la obra. En este trabajo intentaremos abordar la pri-mera cuestión a partir de un análisis de uno de los poemas, “Capitán es el viento”, del primer poemario escrito por Hernández Novás, Enigma de las aguas, dejando de lado la relación entre la vida y la obra de este poeta.La selección de este poema en particular, dentro de la gran cantidad de textos que podrían haber servido a los fines de este trabajo, respon-de más a la reunión de diversas imágenes en un único poema antes que a otras razones, ya que uno de los rasgos característicos de este poeta es la coherencia que mantiene a lo largo de toda su obra, publicada e inédita, no solo en lo que respecta a la construcción del sujeto lírico, sino a la selección temática, a las intertextualidades, etc
Energy levels of few electron quantum dots imaged and characterized by atomic force microscopy
Strong confinement of charges in few electron systems such as in atoms,
molecules and quantum dots leads to a spectrum of discrete energy levels that
are often shared by several degenerate quantum states. Since the electronic
structure is key to understanding their chemical properties, methods that probe
these energy levels in situ are important. We show how electrostatic force
detection using atomic force microscopy reveals the electronic structure of
individual and coupled self-assembled quantum dots. An electron addition
spectrum in the Coulomb blockade regime, resulting from a change in cantilever
resonance frequency and dissipation during tunneling events, shows one by one
electron charging of a dot. The spectra show clear level degeneracies in
isolated quantum dots, supported by the first observation of predicted
temperature-dependent shifts of Coulomb blockade peaks. Further, by scanning
the surface we observe that several quantum dots may reside on what
topologically appears to be just one. These images of grouped weakly and
strongly coupled dots allow us to estimate their relative coupling strengths.Comment: 11 pages, 6 figure
Antenna reconfiguration verification and validation
A method of testing the electrical functionality of an optically controlled switch in a reconfigurable antenna is provided. The method includes configuring one or more conductive paths between one or more feed points and one or more test point with switches in the reconfigurable antenna. Applying one or more test signals to the one or more feed points. Monitoring the one or more test points in response to the one or more test signals and determining the functionality of the switch based upon the monitoring of the one or more test points
Molecular Motor Constructed from a Double-Walled Carbon Nanotube Driven by Axially Varying Voltage
A new molecular motor is conceptually constructed from a double-walled carbon
nanotube (DWNT) consisting of a long inner single-walled carbon nanotube (SWNT)
and a short outer SWNT with different chirality. The interaction between inner
and outer tubes is the sum of the Lennard-Jones potentials between carbon atoms
in inner tube and those in outer one. Within the framework of
Smoluchowski-Feynman ratchet, it is theoretically shown that this system in an
isothermal bath will exhibit a unidirectional rotation in the presence of a
varying axial electrical voltage.Comment: 11 pages + 3 figure
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