2,686 research outputs found
Teaching multidisciplinary engineering using concepts and technology of WSN
This paper discusses teaching and learning strategies of Wireless Sensor Networks technology in a new postgraduate subject run at the Faculty of Engineering and IT, University of Technology, Sydney. The aim is to present the role of using practice based and multidisciplinary methodologies in the context of new ICT technologies. This includes shared experiences, observations and common problems experienced in teaching new concepts and paradigms, standards, protocols and algorithms, embedded systems and sensor technologies. The theory of WSN is applied as a driver of system development for the group projects that students undertake in the subject. © 2012 IEEE
Extinction Map of Baade's Window
Recently Wo\'zniak \& Stanek (1996) proposed a new method to investigate
interstellar extinction, based on two band photometry, which uses red clump
stars as a means to construct the reddening curve. I apply this method to the
color-magnitude diagrams obtained by the Optical Gravitational Lensing
Experiment (OGLE) to construct an extinction map of region of
Baade's Window, with resolution of . Such a map should be
useful for studies of this frequently observed region of the Galactic bulge.
The map and software useful for its applications are available via {\tt
anonymous ftp}. The total extinction varies from to
within the field of view centered on (18:03:20.9,--30:02:06), i.e. . The
ratio is determined with this new method.Comment: revised version accepted for publication in ApJ Letters, 8 pages,
uuencoded PostScript with 4 figures included; complete paper available
through WWW at http://www.astro.princeton.edu/~library/prep.html; tables and
auxiliary software available at
ftp://www.astro.princeton.edu/stanek/Extinctio
SU(2) × SU(2) × U(1) basis for symmetric SO(6) representations : matrix elements of the generators
Matrix elements of the group generators for the symmetric irreducible representations of SO(6) are explicitly calculated in a closed form employing the decomposition chain SO(6) ⊃ SU(2) x SU(2) x U(1) (which is different from the well known Wigner supermultiplet scheme). The relation to the Gel'fand Tsetlin method using SO(6) ⊃ SO(5) ⊃ ... ⊃ SO(2) is indicated. An example of a physical application is given
Applications of cooperative WSN in homecare systems
Cooperation plays the crucial role in shared space of the homecare processes. It is a rather hard task to ensure effective cooperation in home care environment. This is due to variability of schedules, tasks and mobility of both patients and carers. In this paper, we discuss sensor network technology that can facilitate and improve home care cooperation scenarios. We present methodology, recommendations and applications for incorporating a WSN based solution in various areas of Homecare. We argue that even the most difficult areas of cooperation between patients and their carers such as: information retrieval, information dissemination, scheduling, coordination of short and long-term treatment can be supported by WSN based solutions. Finally, we discuss sensor network design approaches for incorporating smart communication devices and sensors to support health care workers and their patients in their daily activities. The network of smart sensors can help to maintain awareness of the activities of all stakeholders and the need to integrate communication and computer technology with the requirements of effective aged care infrastructure. © 2008 IEEE
Are the Ogle Microlenses in the Galactic Bar?
The analysis of the first two years of OGLE data revealed 9 microlensing
events of the galactic bulge stars, with the characteristic time scales in the
range days, where . The optical depth to
microlensing is larger than , in excess of
current theoretical estimates, indicating a much higher efficiency for
microlensing by either bulge or disk lenses. We argue that the lenses are
likely to be ordinary stars in the galactic bar, which has its long axis
elongated towards us. A relation between and the lens masses remains
unknown until a quantitative model of bar microlensing becomes available. At
this time we have no evidence that the OGLE events are related to dark matter.
The geometry of lens distribution can be determined observationally when the
microlensing rate is measured over a larger range of galactic longitudes, like
, and the relative proper motions of the galactic bulge
(bar) stars are measured with the HST.Comment: 10 pages, 2 figures, revised version accepted for the publication in
ApJL, uses AAS LaTeX aaspp.sty macro, PostScript figures and PostScript
version of the paper available through anonymous ftp from
astro.princeton.edu, directory stanek/tau, or on reques
The tensor part of the Skyrme energy density functional. III. Time-odd terms at high spin
This article extends previous studies on the effect of tensor terms in the
Skyrme energy density functional by breaking of time-reversal invariance. We
have systematically probed the impact of tensor terms on properties of
superdeformed rotational bands calculated within the cranked
Hartree-Fock-Bogoliubov approach for different parameterizations covering a
wide range of values for the isoscalar and isovector tensor coupling constants.
We analyze in detail the contribution of the tensor terms to the energies and
dynamical moments of inertia and study their impact on quasi-particle spectra.
Special attention is devoted to the time-odd tensor terms, the effect of
variations of their coupling constants and finite-size instabilities.Comment: 28 pages, 34 figure
Modelling the Galactic Bar Using Red Clump Giants
The color-magnitude diagrams of stars obtained for 12
fields across the Galactic bulge with the OGLE project reveal a well-defined
population of bulge red clump giants. We find that the distributions of the
apparent magnitudes of the red clump stars are systematically fainter when
moving towards lower galactic fields. The most plausible explanation of
this distinct trend is that the Galactic bulge is a bar, whose nearest end lies
at positive galactic longitude. We model this Galactic bar by fitting for all
fields the observed luminosity functions in the red clump region of the
color-magnitude diagram. We find that almost regardless of the analytical
function used to describe the 3-D stars distribution of the Galactic bar, the
resulting models have the major axis inclined to the line of sight by
, with axis ratios corresponding to . This
puts a strong constraint on the possible range of the Galactic bar models.
Gravitational microlensing can provide us with additional constrains on the
structure of the Galactic bar.Comment: submitted to the New Astronomy, 27 pages, 11 figures; also available
at ftp://www.astro.princeton.edu/stanek/Barmodel and through WWW at
http://www.astro.princeton.edu/~library/prep.htm
Color-Magnitude Diagram Distribution of the Bulge Red Clump Stars - Evidence for the Galactic Bar
The color-magnitude diagrams of stars obtained for 13
fields towards the Galactic bulge with the OGLE project reveal a well-defined
population of bulge red clump stars. We find that the distributions of the
extinction-adjusted apparent magnitudes of the red clump stars in fields lying
at in galactic longitude differ by . Assuming
that the intrinsic luminosity distribution of the red clump stars is the same
on both sides of the Galactic center, this implies that the distances to the
red clump stars in the two fields differ by a factor of . A
plausible explanation of the observed difference in the luminosity distribution
is that the Galactic bulge is a triaxial structure, or bar, which is inclined
to the line of sight by no more than , with the part of the bar at the
positive galactic longitude being closer to us. This agrees rather well with
other studies indicating the presence of the bar in the center of the Galaxy.
Color-magnitude diagram data are accessible over the computer network with
anonymous {\tt ftp}.Comment: 10 pages, 6 figures, uses AAS LaTeX aaspp.sty macro, PostScript
figures available through the anonymous ftp or on request, accepted for the
publication in the ApJ
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