1,281 research outputs found
Systematic Electromagnetic Interference Filter Design Based on Information From In-Circuit Impedance Measurements
Based on a two-probe measurement approach, the noise source and noise termination impedances of a switched-mode power supply (SMPS) under its normal operating condition are measured. With the accurate noise source and noise termination impedances, an electromagnetic interference (EMI) filter can be optimally designe
Поліфонічні прийоми в духовних творах Ігоря Мацієвського
У пропонованій статті розглядаються поліфонічні прийоми в деяких зразках духовної вокально-хорової та інструментальної музики сучасного представника української діаспори в Петербурзі, провідного вченого-етноінструментознавця й композитора Ігоря Мацієвського. Знання глибинних законів етномузики слов’янських народів дозволило йому стати не лише фундатором української й російської етноорганології, але й автором оригінальних композицій, у мові яких органічно поєднуються академічність, авангардизм, елементи гуцульської, лемківської, підляської, білоруської, польської та російської народної музики.В статье рассматриваются полифонические приёмы в некоторых образцах духовной вокально-хоровой и инструментальной музыки современного представителя украинськой диаспоры в Санкт-Петербурге, выдающегося учёного и композитора Игоря Мациевского.The polyphonic methods in some examples of the spiritual vocal-choral and instrumental music of Igor Matsiyevsky, a modern representative of the Ukrainian Diaspora in St. Petersburg, are studied in the article. The profound knowledge of the very nature of Slavonic ethnical music helped him to become not only a founder of the Ukrainian and Russian ethnoorganology, but also an author of the genuine compositions, in language of which academicism, avant-gardism and the elements of Guzulska, Lemkivska, Pidlyaska, Belorussian, Polish and Russian folk music are organically combined
State sampling dependence of the Hopfield network inference
The fully connected Hopfield network is inferred based on observed
magnetizations and pairwise correlations. We present the system in the glassy
phase with low temperature and high memory load. We find that the inference
error is very sensitive to the form of state sampling. When a single state is
sampled to compute magnetizations and correlations, the inference error is
almost indistinguishable irrespective of the sampled state. However, the error
can be greatly reduced if the data is collected with state transitions. Our
result holds for different disorder samples and accounts for the previously
observed large fluctuations of inference error at low temperatures.Comment: 4 pages, 1 figure, further discussions added and relevant references
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A simple and efficient numerical scheme to integrate non-local potentials
As nuclear wave functions have to obey the Pauli principle, potentials issued
from reaction theory or Hartree-Fock formalism using finite-range interactions
contain a non-local part. Written in coordinate space representation, the
Schrodinger equation becomes integro-differential, which is difficult to solve,
contrary to the case of local potentials, where it is an ordinary differential
equation. A simple and powerful method has been proposed several years ago,
with the trivially equivalent potential method, where non-local potential is
replaced by an equivalent local potential, which is state-dependent and has to
be determined iteratively. Its main disadvantage, however, is the appearance of
divergences in potentials if the wave functions have nodes, which is generally
the case. We will show that divergences can be removed by a slight modification
of the trivially equivalent potential method, leading to a very simple, stable
and precise numerical technique to deal with non-local potentials. Examples
will be provided with the calculation of the Hartree-Fock potential and
associated wave functions of 16O using the finite-range N3LO realistic
interaction.Comment: 8 pages, 2 figures, submitted to Eur. Phys. J.
Measuring the cosmological bulk flow using the peculiar velocities of supernovae
We study large-scale coherent motion in our universe using the existing Type
IA supernovae data. If the recently observed bulk flow is real, then some
imprint must be left on supernovae motion. We run a series of Monte Carlo
Markov Chain runs in various redshift bins and find a sharp contrast between
the z 0.05 data. The$z < 0.05 data are consistent with the bulk
flow in the direction (l,b)=({290^{+39}_{-31}}^{\circ},
{20^{+32}_{-32}}^{\circ}) with a magnitude of v_bulk = 188^{+119}_{-103} km/s
at 68% confidence. The significance of detection (compared to the null
hypothesis) is 95%. In contrast, z > 0.05 data (which contains 425 of the 557
supernovae in the Union2 data set) show no evidence for bulk flow. While the
direction of the bulk flow agrees very well with previous studies, the
magnitude is significantly smaller. For example, the Kashlinsky, et al.'s
original bulk flow result of v_bulk > 600 km/s is inconsistent with our
analysis at greater than 99.7% confidence level. Furthermore, our best-fit bulk
flow velocity is consistent with the expectation for the \Lambda CDM model,
which lies inside the 68% confidence limit.Comment: Version published in JCA
Yet Another Extension of the Standard Model: Oases in the Desert?
We have searched for conceptually simple extensions of the standard model,
and describe here a candidate model which we find attractive. Our starting
point is the assumption that off-diagonal CKM mixing matrix elements are
directly related by lowest order perturbation theory to the quark mass
matrices. This appears to be most easily and naturally implemented by assuming
that all off-diagonal elements reside in the down-quark mass matrix. This
assumption is in turn naturally realized by introducing three generations of
heavy, electroweak-singlet down quarks which couple to the Higgs sector
diagonally in flavor, while mass-mixing off-diagonally with the light
down-quarks. Anomaly cancellation then naturally leads to inclusion of
electroweak vector-doublet leptons. It is then only a short step to completing
the extension to three generations of fundamental representations of E(6).
Assuming only that the third generation B couples to the Higgs sector at least
as strongly as does the top quark, the mass of the B is roughly estimated to
lie between 1.7 TeV and 10 TeV, with lower-generation quarks no heavier. The
corresponding guess for the new leptons is a factor two lower. Within the
validity of the model, flavor and CP violation are ``infrared'' in nature,
induced by semi-soft mass mixing terms, not Yukawa couplings. If the Higgs
couplings of the new quarks are flavor symmetric, then there necessarily must
be at least one ``oasis'' in the desert, induced by new radiative corrections
to the top quark and Higgs coupling constants, and roughly at 1000 TeV.Comment: LaTex, 40 page
CDMS, Supersymmetry and Extra Dimensions
The CDMS experiment aims to directly detect massive, cold dark matter
particles originating from the Milky Way halo. Charge and lattice excitations
are detected after a particle scatters in a Ge or Si crystal kept at ~30 mK,
allowing to separate nuclear recoils from the dominating electromagnetic
background. The operation of 12 detectors in the Soudan mine for 75 live days
in 2004 delivered no evidence for a signal, yielding stringent limits on dark
matter candidates from supersymmetry and universal extra dimensions. Thirty Ge
and Si detectors are presently installed in the Soudan cryostat, and operating
at base temperature. The run scheduled to start in 2006 is expected to yield a
one order of magnitude increase in dark matter sensitivity.Comment: To be published in the proceedings of the 7th UCLA symposium on
sources and detection of dark matter and dark energy in the universe, Marina
del Rey, Feb 22-24, 200
Discovery and Identifictation of Extra Gauge Bosons in e^+e^- -> nu nubar gamma
We examine the sensitivity of the process e+e- -> nu nubar gamma to extra
gauge bosons, Z' and W', which arise in various extensions of the standard
model. The process is found to be sensitive to W' masses up to several TeV,
depending on the model, the center of mass energy, and the assumed integrated
luminosity. If extra gauge bosons were discovered first in other experiments,
the process could also be used to measure Z' nu nubar and W' couplings. This
measurement would provide information that could be used to unravel the
underlying theory, complementary to measurements at the Large Hadron Collider.Comment: 45 pages, 17 postscript figures, Latex. Uses RevTex and epsfi
Single-photon Transistors Based on the Interaction of an Emitter and Surface Plasmons
A symmetrical approach is suggested (Chang DE et al. Nat Phys 3:807, 2007) to realize a single-photon transistor, where the presence (or absence) of a single incident photon in a ‘gate’ field is sufficient to allow (prevent) the propagation of a subsequent ‘signal’ photon along the nanowire, on condition that the ‘gate’ field is symmetrically incident from both sides of an emitter simultaneously. We present a scheme for single-photon transistors based on the strong emitter-surface-plasmon interaction. In this scheme, coherent absorption of an incoming ‘gate’ photon incident along a nanotip by an emitter located near the tip of the nanotip results in a state flip in the emitter, which controls the subsequent propagation of a ‘signal’ photon in a nanowire perpendicular to the axis of the nanotip
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