7,039 research outputs found
Analysis of economics of a TV broadcasting satellite for additional nationwide TV programs
The influence of a TV broadcasting satellite, transmitting four additional TV networks was analyzed. It is assumed that the cost of the satellite systems will be financed by the cable TV system operators. The additional TV programs increase income by attracting additional subscribers. Two economic models were established: (1) each local network is regarded as an independent economic unit with individual fees (cost price model) and (2) all networks are part of one public cable TV company with uniform fees (uniform price model). Assumptions are made for penetration as a function of subscription rates. Main results of the study are: the installation of a TV broadcasting satellite improves the economics of CTV-networks in both models; the overall coverage achievable by the uniform price model is significantly higher than that achievable by the cost price model
Breakdown and recovery of thin gate oxides
Breakdown events are studied in varying test set-ups with a high time resolution. Often a partial recovery from breakdown is observed\ud
within a few ms. Parameters such as device area, stress conditions and parasitic elements prohibit the recovery if they result in a high system impedance. The results suggest the existence of a highly conductive path that can be annihilated during breakdown
Fiscal Austerity and Public Investment: Is the Possible the Enemy of the Necessary?
In most rich democracies one finds a tendency for the share in public finance that is available for discretionary spending to shrink. This is because tax revenues do not keep pace with simultaneous increases in fixed expenditures and growing pressures for fiscal consolidation. The present paper assesses the capacity of governments under conditions of fiscal austerity to shift financial resources within the shrinking share of discretionary expenditure from old to new purposes, and thereby fund future-oriented investment aimed at making societies more equitable and efficient. For this reason an indicator for soft public investment is developed, which includes public spending on education, R&D, family support, and active labor market policy. We present data for Germany, Sweden, and the United States for the years 1981 to 2007 in order to explore the general dynamics of consolidation policies under the expectation that far more ambitious consolidation attempts will be made in the coming decade. Our results suggest that the capacity of governments to shift resources towards soft public investment decreases as pressures for fiscal consolidation increase.In den meisten reichen Demokratien lässt sich die Tendenz ausmachen, dass der Anteil diskretionärer Ausgaben an den öffentlichen Haushalten zurückgeht. Ursächlich dafür ist, dass die Steuereinnahmen nicht hoch genug sind, um die parallele Zunahme gebundener Ausgaben sowie den gestiegenen Konsolidierungsdruck auffangen zu können. Das Papier untersucht, inwiefern Regierungen unter den Bedingungen fiskalischer Austerität in der Lage sind, finanzielle Mittel innerhalb des diskretionären Ausgabenanteils von alten zu neuen Aufgaben zu verschieben. Dies betrifft insbesondere die Finanzierung zukunftsorientierter Investitionen, die darauf abzielen, Gesellschaften gerechter und effizienter zu gestalten. Zu diesem Zweck wird ein Indikator für "weiche" öffentliche Investitionen entworfen, der Ausgaben für Bildung, Forschung und Entwicklung, Familienunterstützung und aktive Arbeitsmarktpolitik enthält. Angesichts der Erwartung weit ambitionierterer Konsolidierungsversuche im kommenden Jahrzehnt werden auf der Basis von Daten für Deutschland, Schweden und den Vereinigten Staaten für die Jahre 1981 bis 2007 allgemeine Dynamiken der Konsolidierungspolitik herausgearbeitet. Die Ergebnisse weisen darauf hin, dass die Fähigkeit von Regierungen, mehr Ressourcen für "weiche" Investitionen bereitzustellen, in dem Maße abnimmt, wie der Konsolidierungsdruck zunimmt.1 Introduction 2 Public investment: "Hard" and "soft" 3 Method and case selection 4 Variables and data Soft public investment Fiscal stress 5 Results Germany Sweden United States 6 Democratic state capacity in decline 7 Conclusion
Low autocorrelated multi-phase sequences
The interplay between the ground state energy of the generalized Bernasconi
model to multi-phase, and the minimal value of the maximal autocorrelation
function, , , is examined analytically and
the main results are: (a) The minimal value of is
significantly smaller than the typical value for random
sequences . (b) over all sequences
of length N is obtained in an energy which is about 30% above the ground-state
energy of the generalized Bernasconi model, independent of the number of phases
m. (c) The maximal merit factor grows linearly with m. (d) For a
given N, indicating that for m=N,
, i.e. a Barker code exits. The analytical results are
confirmed by simulations.Comment: 4 pages, 4 figure
Non-uniformly receding contact line breaks axisymmetric flow patterns
We investigate the internal flow pattern of an evaporating droplet using
tomographic particle image velocimetry (PIV) when the contact line
non-uniformly recedes. We observe a three-dimensional azimuthal vortex pair
while the contact line non-uniformly recedes and the symmetry-breaking flow
field is maintained during the evaporation. Based on the experimental results,
we show that the vorticity magnitude of the internal flow is related to the
relative contact line motion. Furthermore, to explain how the azimuthal vortex
pair flow is created, we develop a theoretical model by taking into account the
relation between the contact line motion and evaporating flux. Finally, we show
that the theoretical model has a good agreement with experimental results
A Non-Disordered Glassy Model with a Tunable Interaction Range
We introduce a non-disordered lattice spin model, based on the principle of
minimizing spin-spin correlations up to a (tunable) distance R. The model can
be defined in any spatial dimension D, but already for D=1 and small values of
R (e.g. R=5) the model shows the properties of a glassy system: deep and well
separated energy minima, very slow relaxation dynamics, aging and non-trivial
fluctuation-dissipation ratio.Comment: 4 pages, 5 figure
Internal mode mechanism for collective energy transport in extended systems
We study directed energy transport in homogeneous nonlinear extended systems
in the presence of homogeneous ac forces and dissipation. We show that the
mechanism responsible for unidirectional motion of topological excitations is
the coupling of their internal and translation degrees of freedom. Our results
lead to a selection rule for the existence of such motion based on resonances
that explains earlier symmetry analysis of this phenomenon. The direction of
motion is found to depend both on the initial and the relative phases of the
two harmonic drivings, even in the presence of noise.Comment: Final version, to appear in Physical Review Letter
Soliton ratchets in homogeneous nonlinear Klein-Gordon systems
We study in detail the ratchet-like dynamics of topological solitons in
homogeneous nonlinear Klein-Gordon systems driven by a bi-harmonic force. By
using a collective coordinate approach with two degrees of freedom, namely the
center of the soliton, , and its width, , we show, first, that
energy is inhomogeneously pumped into the system, generating as result a
directed motion; and, second, that the breaking of the time shift symmetry
gives rise to a resonance mechanism that takes place whenever the width
oscillates with at least one frequency of the external ac force. In addition,
we show that for the appearance of soliton ratchets, it is also necesary to
break the time-reversal symmetry. We analyze in detail the effects of
dissipation in the system, calculating the average velocity of the soliton as a
function of the ac force and the damping. We find current reversal phenomena
depending on the parameter choice and discuss the important role played by the
phases of the ac force. Our analytical calculations are confirmed by numerical
simulations of the full partial differential equations of the sine-Gordon and
systems, which are seen to exhibit the same qualitative behavior. Our
results are in agreement with recent experimental work on dissipation induced
symmetry breaking.Comment: Minor corrections, several references added, accepted for publication
in Chao
- …