1,051,418 research outputs found
Numerical program for analysis of three-dimensional supersonic exhaust flow fields (CHAR 3D)
Choice of reference plane orientation depends on specific nozzle geometry, with different configurations requiring different reference plane systems. In addition, for given configuration several reference systems may be used in different regions of flow field, so each system is locally aligned with flow
Elliptic flow contribution to two-particle correlations at different orientations to the reaction plane
Collective anisotropic particle flow, a general phenomenon present in
relativistic heavy-ion collisions, can be separated from direct
particle-particle correlations of different physics origin by virtue of its
specific azimuthal pattern. We provide expressions for flow-induced
two-particle azimuthal correlations, if one of the particles is detected under
fixed directions with respect to the reaction plane. We consider an ideal case
when the reaction plane angle is exactly known, as well as present the general
expressions in case of finite event-plane resolution. We foresee applications
for the study of generic two-particle correlations at large transverse momentum
originating from jet fragmentation.Comment: 5 pages, 3 figures, to be published as Rapid Communications in
Phys.Rev.C Re-submit paper to with small improvements in text for better
understanding, some minor changes in notation, and correcting one formula
where a summation was forgotten. One new reference, one reference to
conference report removed since full paper was already reference
Egocentric Reference Frame Bias In The Palmar Haptic Perception Of Surface Orientation
The effect of egocentric reference frames on palmar haptic perception of orientation was investigated in vertically separated locations in a sagittal plane. Reference stimuli to be haptically matched were presented either haptically (to the contralateral hand) or visually. As in prior investigations of haptic orientation perception, a strong egocentric bias was found, such that haptic orientation matches made in the lower part of personal space were much lower (i.e., were perceived as being higher) than those made at eye level. The same haptic bias was observed both when the reference surface to be matched was observed visually and when bimanual matching was used. These findings support the conclusion that, despite the presence of an unambiguous allocentric (gravitational) reference frame in vertical planes, haptic orientation perception in the sagittal plane reflects an egocentric bias
Cross talk in phase-coded holographic memories
The cross talk between holograms multiplexed with Walsh-Hadamard phase codes is analyzed. Each hologram is stored with a reference beam that consists of N phase-coded plane waves. The signal-to-noise ratio (SNR) is calculated for a recording schedule for which the center of each stored image coincides with the nulls of the selectivity function for the adjacent plane-wave components of the reference beam. The SNR characteristics for phase coding with Walsh-Hadamard phase codes are then compared with the SNR for angle and wavelength multiplexing
Reference-Plane Invariant Method for Measuring Electromagnetic Parameters of Materials
This paper presents a simple and effective wideband method for the
determination of material properties, such as the complex index of refraction
and the complex permittivity and permeability. The method is explicit
(non-iterative) and reference-plane invariant: it uses a certain combination of
scattering parameters in conjunction with group-velocity data. This technique
can be used to characterize both dielectric and magnetic materials. The
proposed method is verified experimentally within a frequency range between 2
to 18 GHz on polytetrafluoroethylene and polyvinylchloride samples. A
comprehensive error and stability analysis reveals that, similar to other
methods based on transmission/reflection measurement, the uncertainties are
larger at low frequencies and at the Fabry-Perot resonances.Comment: 12 pages, 21 figure
Calibration standard for dynamic evaluation of a profile-plotter
Template is used for evaluation of the dynamic characteristics and accuracy of the plotter. It has a profile composed of surfaces parallel to and at known distances from a reference plane, plane, the diverse surfaces being connected by slopes of known angles and blended by cylindrical developments of known radii
Measurement of optical to electrical and electrical to optical delays with ps-level uncertainty
We present a new measurement principle to determine the absolute time delay
of a waveform from an optical reference plane to an electrical reference plane
and vice versa. We demonstrate a method based on this principle with 2 ps
uncertainty. This method can be used to perform accurate time delay
determinations of optical transceivers used in fibre-optic time-dissemination
equipment. As a result the time scales in optical and electrical domain can be
related to each other with the same uncertainty. We expect this method to break
new grounds in high-accuracy time transfer and absolute calibration of
time-transfer equipment
(-1)-enumeration of plane partitions with complementation symmetry
We compute the weighted enumeration of plane partitions contained in a given
box with complementation symmetry where adding one half of an orbit of cubes
and removing the other half of the orbit changes the weight by -1 as proposed
by Kuperberg. We use nonintersecting lattice path families to accomplish this
for transpose-complementary, cyclically symmetric transpose-complementary and
totally symmetric self-complementary plane partitions. For symmetric
transpose-complementary and self-complementary plane partitions we get partial
results. We also describe Kuperberg's proof for the case of cyclically
symmetric self-complementary plane partitions.Comment: 41 pages, AmS-LaTeX, uses TeXDraw; reference adde
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