131 research outputs found
The clustering of galaxies with pseudo bulge and classical bulge in the local Universe
We investigate the clustering properties and close neighbour counts for
galaxies with different types of bulges and stellar masses. We select samples
of "classical" and "pseudo" bulges, as well as "bulge-less" disk galaxies,
based on the bulge/disk decomposition catalog of SDSS galaxies provided by
Simard et al. (2011). For a given galaxy sample we estimate: the projected
two-point cross-correlation function with respect to a spectroscopic reference
sample, w_p(r_p), and the average background-subtracted neighbour count within
a projected separation using a photometric reference sample, N_neighbour(<r_p).
We compare the results with the measurements of control samples matched in
color, concentration and redshift. We find that, when limited to a certain
stellar mass range and matched in color and concentration, all the samples
present similar clustering amplitudes and neighbour counts on scales above
~0.1h^{-1}Mpc. This indicates that neither the presence of a central bulge, nor
the bulge type is related to intermediate-to-large scale environments. On
smaller scales, in contrast, pseudo-bulge and pure-disk galaxies similarly show
strong excess in close neighbour count when compared to control galaxies, at
all masses probed. For classical bulges, small-scale excess is also observed
but only for M_stars < 10^{10} M_sun; at higher masses, their neighbour counts
are similar to that of control galaxies at all scales. These results imply
strong connections between galactic bulges and galaxy-galaxy interactions in
the local Universe, although it is unclear how they are physically linked in
the current theory of galaxy formation.Comment: 14 pages, 16 figures, accepted for publication in MNRA
Otkrivanje pogreške u analognim sklopovima analizom relativne amplitude i faze
A new method for detection of parametric faults occurring in analog circuits based on relative amplitude and relative phase analysis of the Circuit Under Test (CUT) is proposed. The relative amplitude is the common power change of the signals and the relative phase presents the relative phase offset of the signals. In the proposed method, the value of each component of the CUT is varied within its tolerance limit using Monte Carlo simulation. The upper and lower bounds of relative amplitude and phase of the CUT sampling series are obtained. While testing, the relative amplitude and phase value of the analog circuit are obtained. If any one of the relative amplitude and phase values exceed the bounds then the CUT is declared faulty. The effectiveness of the proposed method is validated through HSpice/MATLAB simulations of two benchmark circuits and the practical circuit test of Tow-Thomas circuit.U ovome članku predložena je nova metoda otkrivanja parametarskih pogrešaka u analognim sklopovima temeljena na analizi relativne amplitude i faze promatranog sklopa (eng. Circuit Under Test, CUT). Relativna amplituda predstavlja zajedničku promjenu snage signala, dok relativna faza predstavlja pomak u fazi među signalima. U predloženoj metodi, koristeći Monte Carlo simulacije, vrijednost svake komponente CUT-a mijenja se unutar svojih granica tolerancije. Na taj način dobivaju se gornja i donja granica relativne amplitude i faze CUT uzoraka, dok se sama relativna amplituda i faza dobivaju tijekom testiranja. U slučaju da ijedan od tih dvaju faktora prelazi granicu, CUT se proglašava neispravnim. Učinkovitost predložene metode ispitana je pomoću HSpice/MATLAB simulacija nad dva referentna sklopa te na Tow-Thomas sklopu
Relative left Bongartz completions and their compatibility with mutations
In this paper, we introduce relative left Bongartz completions for a given
basic -rigid pair in the module category of a finite dimensional
algebra . They give a family of basic -tilting pairs containing
as a direct summand. We prove that relative left Bongartz completions
have nice compatibility with mutations. Using this compatibility we are able to
study the existence of maximal green sequences under -tilting reduction.
We also explain our construction and some of the results in the setting of
silting theory.Comment: 21 page
Handling Fault Diagnosis Problem of Linear-Analogue Circuits with Voltage Phasor Measurement
This paper proposes a novel method to estimate
the influence of hard-fault in linear-analogue circuit system
based on the measurement of voltage phasor with assistant
branch introduced. Furthermore, a new fault diagnosis strategy
based on the voltage phasor modeling is established, and the
tolerance influence on the corresponding voltage measurement
is also discussed. The actual analogue circuit test shows us
that the proposed method is effective and reliable to locate the
accurate fault signature in voltage measurement for the fault
diagnosis. As a matter of fact, it includes both the amplitude and
phase information in a complex value form when the linear-analogue
circuit is under the AC test. Besides, it can be also
applied to ambiguous groups and the sensitive test-frequencies
determination in the process of fault diagnosis,while the effectiveness
of multifrequencies test has also been testified through
test-frequencies sweeping investigation and the maximum error
evaluation of fault component value in the second circuit example
- …