472 research outputs found
Retrieval of Infotainment System Artifacts from Vehicles Using iVe
The analysis of mobile devices and hard drives has been the focus of the digital forensics world for years, but there is another source of potential evidence not often considered: vehicles. Many of today’s “connected cars” have systems that function like computers, storing information they process including user data from devices synced to the system. There has been little to no research done regarding what types of user artifacts can be found on the system, how long these artifacts remain, whether or not the user can remove those artifacts, and whether certain systems provide more information than others. For this study, two different makes and models of vehicle infotainment systems were used for data acquisition: a Uconnect® system and a Toyota™ Extension Box. It was found that the Toyota™ system provided a significant amount of user information (contacts, call logs, media file information, and locations), while the Uconnect® system provided only locations. This indicates valuable user data can be obtained in this manner
Proposal for a low cost close air support aircraft for the year 2000: The Raptor
The Raptor is a proposed low cost Close Air Support (CAS) aircraft for the U.S. Military. The Raptor incorporates a 'cranked arrow' wing planform, and uses canards instead of a traditional horizontal tail. The Raptor is designed to be capable of responsive delivery of effective ordnance in close proximity to friendly ground forces during the day, night, and 'under the weather' conditions. Details are presented of the Raptor's mission, configuration, performance, stability and control, ground support, manufacturing, and overall cost to permit engineering evaluation of the proposed design. A description of the design process and analysis methods used is also provided
Book Reviews
GOVERNMENTAL REORGANIZATIONS: CASES AND COMMENTARY. Edited by Frederick C. Moshe.
THE CHANGING LAW OF NATIONS: ESSAYS ON INTERNATIONAL LAW. By Josef L. Kunz.
THE BOOM IN GOING BUST: THE GROWING SCANDAL IN PERSONAL BANKRUPTCY. By George Sullivan.
INVISIBLE WITNESS: THE USE AND ABUSE OF THE NEW TECHNOLOGY OF CRIME INVESTIGATION. By William W. Turner
The cross-correlation search for periodic gravitational waves
In this paper we study the use of cross-correlations between multiple
gravitational wave (GW) data streams for detecting long-lived periodic signals.
Cross-correlation searches between data from multiple detectors have
traditionally been used to search for stochastic GW signals, but recently they
have also been used in directed searches for periodic GWs. Here we further
adapt the cross-correlation statistic for periodic GW searches by taking into
account both the non-stationarity and the long term-phase coherence of the
signal. We study the statistical properties and sensitivity of this search, its
relation to existing periodic wave searches, and describe the precise way in
which the cross-correlation statistic interpolates between semi-coherent and
fully-coherent methods. Depending on the maximum duration over we wish to
preserve phase coherence, the cross-correlation statistic can be tuned to go
from a standard cross-correlation statistic using data from distinct detectors,
to the semi-coherent time-frequency methods with increasing coherent time
baselines, and all the way to a full coherent search. This leads to a unified
framework for studying periodic wave searches and can be used to make informed
trade-offs between computational cost, sensitivity, and robustness against
signal uncertainties.Comment: 17 pages, 1 figure, RevTeX
Quasistationary binary inspiral. I. Einstein equations for the two Killing vector spacetime
The geometry of two infinitely long lines of mass moving in a fixed circular
orbit is considered as a toy model for the inspiral of a binary system of
compact objects due to gravitational radiation. The two Killing fields in the
toy model are used, according to a formalism introduced by Geroch, to describe
the geometry entirely in terms of a set of tensor fields on the two-manifold of
Killing vector orbits. Geroch's derivation of the Einstein equations in this
formalism is streamlined and generalized. The explicit Einstein equations for
the toy model spacetime are derived in terms of the degrees of freedom which
remain after a particular choice of gauge.Comment: 37 pages, REVTeX, one PostScript Figure included with epsfig; minor
formatting changes and copyright notice added for journal publicatio
Progress on stochastic background search codes for LIGO
One of the types of signals for which the LIGO interferometric gravitational
wave detectors will search is a stochastic background of gravitational
radiation. We review the technique of searching for a background using the
optimally-filtered cross-correlation statistic, and describe the state of plans
to perform such cross-correlations between the two LIGO interferometers as well
as between LIGO and other gravitational-wave detectors, in particular the
preparation of software to perform such data analysis.Comment: 7 pages, 1 encapsulated PostScript figure, uses IOP class files,
submitted to the proceedings of the 4th Amaldi meeting (which will be
published in Classical and Quantum Gravity
Modeling the decoherence of spacetime
The question of whether unobserved short-wavelength modes of the
gravitational field can induce decoherence in the long-wavelength modes (``the
decoherence of spacetime'') is addressed using a simplified model of
perturbative general relativity, related to the Nordstrom-Einstein-Fokker
theory, where the metric is assumed to be conformally flat. For some
long-wavelength coarse grainings, the Feynman-Vernon influence phase is found
to be effective at suppressing the off-diagonal elements of the decoherence
functional. The requirement that the short-wavelength modes be in a
sufficiently high-temperature state places limits on the applicability of this
perturbative approach.Comment: 38 pages, REVTeX; 7 diagrams and 6 PostScript figures included via
epsfig. Final cosmetic changes made at publicatio
Stochastic Background Search Correlating ALLEGRO with LIGO Engineering Data
We describe the role of correlation measurements between the LIGO
interferometer in Livingston, LA, and the ALLEGRO resonant bar detector in
Baton Rouge, LA, in searches for a stochastic background of gravitational
waves. Such measurements provide a valuable complement to correlations between
interferometers at the two LIGO sites, since they are sensitive in a different,
higher, frequency band. Additionally, the variable orientation of the ALLEGRO
detector provides a means to distinguish gravitational wave correlations from
correlated environmental noise. We describe the analysis underway to set a
limit on the strength of a stochastic background at frequencies near 900 Hz
using ALLEGRO data and data from LIGO's E7 Engineering Run.Comment: 8 pages, 2 encapsulated PostScript figures, uses IOP class files,
submitted to the proceedings of the 7th Gravitational Wave Data Analysis
Workshop (which will be published in Classical and Quantum Gravity
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