2,530 research outputs found
Fluid Models of Many-server Queues with Abandonment
We study many-server queues with abandonment in which customers have general
service and patience time distributions. The dynamics of the system are modeled
using measure- valued processes, to keep track of the residual service and
patience times of each customer. Deterministic fluid models are established to
provide first-order approximation for this model. The fluid model solution,
which is proved to uniquely exists, serves as the fluid limit of the
many-server queue, as the number of servers becomes large. Based on the fluid
model solution, first-order approximations for various performance quantities
are proposed
Frictional drag between non-equilibrium charged gases
The frictional drag force between separated but coupled two-dimensional
electron gases of different temperatures is studied using the non-equilibrium
Green function method based on the separation of center-of-mass and relative
dynamics of electrons. As the mechanisms of producing the frictional force we
include the direct Coulomb interaction, the interaction mediated via virtual
and real TA and LA phonons, optic phonons, plasmons, and TA and LA
phonon-electron collective modes. We found that, when the distance between the
two electron gases is large, and at intermediate temperature where plasmons and
collective modes play the most important role in the frictional drag, the
possibility of having a temperature difference between two subsystems modifies
greatly the transresistivity.Comment: 8figure
Performance of an objective fabric pilling evaluation method
In previous work, we established the principle of objective fabric pilling evaluation based on two-dimensional dual-tree complex wavelet transform (2DDTCWT) image reconstruction and non-linear classification using a neural network. This proof-of-principle work was performed using standard pilling test images. Here, we demonstrate the practical operation of the objective pilling evaluation method using a large set of real fabric pilling samples. We show that piling classification results from a trained multiple-layer perceptron neural network achieve a regression correlation of approximately 96% with the corresponding human expert pilling ratings.<br /
Strong Southward Transport Events Due to Typhoons in the Taiwan Strait
Transport through the Taiwan Strait under the influence of five typhoons was investigated using both buoy observations and numerical model simulations during the period of 27 August to 5 October 2005. The results show that the effects of typhoons on the Taiwan Strait and its adjacent sea area caused strong southward transport events in the Taiwan Strait, which changed the direction of the Taiwan Strait northward transport temporarily. Typhoon-generated local wind stress and/or along-strait water level gradient were the direct driving factors in these southward transport events. The numerical results show that the Coriolis force made a negative contribution to these events and the contribution of the along-strait momentum gradient was insignificant
Evaluation of the Dynamic Characteristics of AZ91D Crankcase Covers and Boxes
Dynamic tests are performed on similarly structured crankcase covers and boxes made of AZ91D magnesium and A380 aluminum alloys. The real vibration and noise control effect of an AZ91D magnesium alloy is evaluated, based on the behavior of the integral frequency response function, which is derived from the measured surface vibrations of the crankcase cover under operating conditions. The results indicate that crankcase covers and boxes made of AZ91D magnesium and A380 aluminum alloys with the same geometry possess similar normal characteristics. Both materials are interchangeable. However, the stiffness of AZ91D crankcase covers and boxes is poor. It is also difficult to obtain good engineering vibration and noise effects in the real structure due to an AZ91D high damping capacity. At the same excitation and frequency response at different structure characteristics, the measurement analysis of time-domain response indicates that methods to strengthen the crankcase box stiffness, such as embedding a main bearing steel sleeve, is favorable for improving the dynamic characteristics of an AZ91D crankcase box.ΠΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΠΈΡΠΏΡΡΠ°Π½ΠΈΡ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΈ Π½Π° ΠΊΠ°ΡΡΠ΅ΡΠ½ΡΡ
ΠΊΡΡΡΠΊΠ°Ρ
ΠΈ ΠΏΠΎΠ΄Π΄ΠΎΠ½Π°Ρ
Π°Π½Π°Π»ΠΎΠ³ΠΈΡΠ½ΠΎΠΉ ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠΈ, ΠΈΠ·Π³ΠΎΡΠΎΠ²Π»Π΅Π½Π½ΡΡ
ΠΈΠ· ΠΌΠ°Π³Π½ΠΈΠ΅Π²ΠΎΠ³ΠΎ AZ91D ΠΈ Π°Π»ΡΠΌΠΈΠ½ΠΈΠ΅Π²ΠΎΠ³ΠΎ Π380 ΡΠΏΠ»Π°Π²ΠΎΠ². ΠΡΠ΅Π½Π΅Π½ ΡΡΡΠ΅ΠΊΡ ΠΎΡ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ ΠΌΠ°Π³Π½ΠΈΠ΅Π²ΠΎΠ³ΠΎ ΡΠΏΠ»Π°Π²Π° AZ91D Π΄Π»Ρ ΠΊΠΎΠ½ΡΡΠΎΠ»Ρ ΡΠ΅Π°Π»ΡΠ½ΠΎΠΉ Π²ΠΈΠ±ΡΠ°ΡΠΈΠΈ ΠΈ ΡΡΠΌΠ° Π½Π° ΠΎΡΠ½ΠΎΠ²Π°Π½ΠΈΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠ° ΠΈΠ½ΡΠ΅Π³ΡΠ°Π»ΡΠ½ΠΎΠΉ ΡΠ°ΡΡΠΎΡΠ½ΠΎΠΉ ΡΡΠ½ΠΊΡΠΈΠΈ ΠΎΡΠΊΠ»ΠΈΠΊΠ°, ΠΏΠΎΠ»ΡΡΠ΅Π½Π½ΠΎΠΉ ΠΏΠΎ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°ΠΌ ΠΈΠ·ΠΌΠ΅ΡΠ΅Π½ΠΈΡ ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠ½ΠΎΠΉ Π²ΠΈΠ±ΡΠ°ΡΠΈΠΈ ΠΊΠ°ΡΡΠ΅ΡΠ½ΠΎΠΉ ΠΊΡΡΡΠΊΠΈ Π² ΡΠ°Π±ΠΎΡΠ΅ΠΌ ΡΠ΅ΠΆΠΈΠΌΠ΅. Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΏΠΎΠΊΠ°Π·ΡΠ²Π°ΡΡ, ΡΡΠΎ ΠΊΠ°ΡΡΠ΅ΡΠ½ΡΠ΅ ΠΊΡΡΡΠΊΠΈ ΠΈ ΠΏΠΎΠ΄Π΄ΠΎΠ½Ρ, ΠΈΠ·Π³ΠΎΡΠΎΠ²Π»Π΅Π½Π½ΡΠ΅ ΠΈΠ· ΠΌΠ°Π³Π½ΠΈΠ΅Π²ΠΎΠ³ΠΎ AZ91D ΠΈ Π°Π»ΡΠΌΠΈΠ½ΠΈΠ΅Π²ΠΎΠ³ΠΎ Π380 ΡΠΏΠ»Π°Π²ΠΎΠ², Ρ ΠΎΠ΄ΠΈΠ½Π°ΠΊΠΎΠ²ΡΠΌΠΈ Π³Π΅ΠΎΠΌΠ΅ΡΡΠΈΡΠ΅ΡΠΊΠΈΠΌΠΈ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠ°ΠΌΠΈ ΠΈΠΌΠ΅ΡΡ Π°Π½Π°Π»ΠΎΠ³ΠΈΡΠ½ΡΠ΅ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΡΠ΅ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ. ΠΠ±Π° ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° Π²Π·Π°ΠΈΠΌΠΎΠ·Π°ΠΌΠ΅Π½ΡΠ΅ΠΌΡ. ΠΠ΄Π½Π°ΠΊΠΎ ΠΊΠ°ΡΡΠ΅ΡΠ½Π°Ρ ΠΊΡΡΡΠΊΠ° ΠΈ ΠΏΠΎΠ΄Π΄ΠΎΠ½ ΠΈΠ· ΡΠΏΠ»Π°Π²Π° AZ91D ΠΎΠ±Π»Π°Π΄Π°ΡΡ Π½ΠΈΠ·ΠΊΠΎΠΉ ΠΆΠ΅ΡΡΠΊΠΎΡΡΡΡ. ΠΠΎΡΡΠΈΡΡ Π½ΠΎΡΠΌΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΡΠΎΠ²Π½Ρ Π²ΠΈΠ±ΡΠ°ΡΠΈΠΈ ΠΈ ΡΡΠΌΠ° Π² ΡΠ΅Π°Π»ΡΠ½ΠΎΠΉ ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠΈ ΡΠ°ΠΊΠΆΠ΅ Π·Π°ΡΡΡΠ΄Π½ΠΈΡΠ΅Π»ΡΠ½ΠΎ, ΠΏΠΎΡΠΊΠΎΠ»ΡΠΊΡ ΡΠΏΠ»Π°Π² AZ91D ΠΎΠ±Π»Π°Π΄Π°Π΅Ρ Π²ΡΡΠΎΠΊΠΎΠΉ Π΄Π΅ΠΌΠΏΡΠΈΡΡΡΡΠ΅ΠΉ ΡΠΏΠΎΡΠΎΠ±Π½ΠΎΡΡΡΡ. ΠΡΠΈ ΠΎΠ΄ΠΈΠ½Π°ΠΊΠΎΠ²ΠΎΠΌ Π²ΠΎΠ·Π±ΡΠΆΠ΄Π΅Π½ΠΈΠΈ ΠΈ ΡΠ°ΡΡΠΎΡΠ½ΠΎΠΉ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠ΅ ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠΈ Ρ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠΌΠΈ ΠΏΠ°ΡΠ°ΠΌΠ΅ΡΡΠ°ΠΌΠΈ Π°Π½Π°Π»ΠΈΠ· ΠΈΠ·ΠΌΠ΅ΡΠ΅Π½ΠΈΡ Π²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ ΠΎΠ±Π»Π°ΡΡΠΈ ΠΏΠΎΠΊΠ°Π·ΡΠ²Π°Π΅Ρ, ΡΡΠΎ ΠΌΠ΅ΡΠΎΠ΄Ρ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΡ ΠΆΠ΅ΡΡΠΊΠΎΡΡΠΈ ΠΊΠ°ΡΡΠ΅ΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄Π΄ΠΎΠ½Π°, Π½Π°ΠΏΡΠΈΠΌΠ΅Ρ Π²ΠΌΠΎΠ½ΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅ Π³Π»Π°Π²Π½ΠΎΠ³ΠΎ ΡΡΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄ΡΠΈΠΏΠ½ΠΈΠΊΠ° ΡΠΊΠΎΠ»ΡΠΆΠ΅Π½ΠΈΡ, ΡΠΏΠΎΡΠΎΠ±ΡΡΠ²ΡΡΡ ΡΠ»ΡΡΡΠ΅Π½ΠΈΡ Π΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊ ΠΊΠ°ΡΡΠ΅ΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄Π΄ΠΎΠ½Π° ΠΈΠ· ΡΠΏΠ»Π°Π²Π° AZ91D
Dynamical Chiral Symmetry Breaking on the Light Front.II. The Nambu--Jona-Lasinio Model
An investigation of dynamical chiral symmetry breaking on the light front is
made in the Nambu--Jona-Lasinio model with one flavor and N colors. Analysis of
the model suffers from extraordinary complexity due to the existence of a
"fermionic constraint," i.e., a constraint equation for the bad spinor
component. However, to solve this constraint is of special importance. In
classical theory, we can exactly solve it and then explicitly check the
property of ``light-front chiral transformation.'' In quantum theory, we
introduce a bilocal formulation to solve the fermionic constraint by the 1/N
expansion. Systematic 1/N expansion of the fermion bilocal operator is realized
by the boson expansion method. The leading (bilocal) fermionic constraint
becomes a gap equation for a chiral condensate and thus if we choose a
nontrivial solution of the gap equation, we are in the broken phase. As a
result of the nonzero chiral condensate, we find unusual chiral transformation
of fields and nonvanishing of the light-front chiral charge. A leading order
eigenvalue equation for a single bosonic state is equivalent to a leading order
fermion-antifermion bound-state equation. We analytically solve it for scalar
and pseudoscalar mesons and obtain their light-cone wavefunctions and masses.
All of the results are entirely consistent with those of our previous analysis
on the chiral Yukawa model.Comment: 23 pages, REVTEX, the version to be published in Phys.Rev.D; Some
clarifications in discussion of the LC wavefunctions adde
<sup>129</sup>I record in the Taal Lake sediment, Philippines: Implication for global fallout of <sup>129</sup>I in low latitude
Subordination Pathways to Fractional Diffusion
The uncoupled Continuous Time Random Walk (CTRW) in one space-dimension and
under power law regime is splitted into three distinct random walks: (rw_1), a
random walk along the line of natural time, happening in operational time;
(rw_2), a random walk along the line of space, happening in operational
time;(rw_3), the inversion of (rw_1), namely a random walk along the line of
operational time, happening in natural time. Via the general integral equation
of CTRW and appropriate rescaling, the transition to the diffusion limit is
carried out for each of these three random walks. Combining the limits of
(rw_1) and (rw_2) we get the method of parametric subordination for generating
particle paths, whereas combination of (rw_2) and (rw_3) yields the
subordination integral for the sojourn probability density in space-time
fractional diffusion.Comment: 20 pages, 4 figure
A polarized beam splitter using an anisotropic medium slab
The propagation of electromagnetic waves in the anisotropic medium with a
single-sheeted hyperboloid dispersion relation is investigated. It is found
that in such an anisotropic medium E- and H-polarized waves have the same
dispersion relation, while E- and H-polarized waves exhibit opposite amphoteric
refraction characteristics. E- (or H-) polarized waves are positively refracted
whereas H- (or E-) polarized waves are negatively refracted at the interface
associated with the anisotropic medium. By suitably using the properties of
anomalous refraction in the anisotropic medium it is possible to realize a very
simple and very efficient beam splitter to route the light. It is shown that
the splitting angle and the splitting distance between E- and H- polarized beam
is the function of anisotropic parameters, incident angle and slab thickness.Comment: 14 pages, 6 figure
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