1,797 research outputs found
The augmented reality framework : an approach to the rapid creation of mixed reality environments and testing scenarios
Debugging errors during real-world testing of remote platforms can be time consuming and expensive
when the remote environment is inaccessible and hazardous such as deep-sea. Pre-real world testing
facilities, such as Hardware-In-the-Loop (HIL), are often not available due to the time and expense
necessary to create them. Testing facilities tend to be monolithic in structure and thus inflexible
making complete redesign necessary for slightly different uses. Redesign is simpler in the short term
than creating the required architecture for a generic facility. This leads to expensive facilities, due
to reinvention of the wheel, or worse, no testing facilities. Without adequate pre-real world testing,
integration errors can go undetected until real world testing where they are more costly to diagnose
and rectify, e.g. especially when developing Unmanned Underwater Vehicles (UUVs).
This thesis introduces a novel framework, the Augmented Reality Framework (ARF), for rapid
construction of virtual environments for Augmented Reality tasks such as Pure Simulation, HIL,
Hybrid Simulation and real world testing. ARFâs architecture is based on JavaBeans and is therefore
inherently generic, flexible and extendable. The aim is to increase the performance of constructing,
reconfiguring and extending virtual environments, and consequently enable more mature and stable
systems to be developed in less time due to previously undetectable faults being diagnosed earlier in
the pre-real-world testing phase. This is only achievable if test harnesses can be created quickly and
easily, which in turn allows the developer to visualise more system feedback making faults easier to
spot. Early fault detection and less wasted real world testing leads to a more mature, stable and
less expensive system.
ARF provides guidance on how to connect and configure user made components, allowing for
rapid prototyping and complex virtual environments to be created quickly and easily. In essence,
ARF tries to provide intuitive construction guidance which is similar in nature to LEGOR
pieces
which can be so easily connected to form useful configurations.
ARF is demonstrated through case studies which show the flexibility and applicability of ARF to
testing techniques such as HIL for UUVs. In addition, an informal study was carried out to asses the
performance increases attributable to ARFâs core concepts. In comparison to classical programming
methods ARFâs average performance increase was close to 200%. The study showed that ARF was
incredibly intuitive since the test subjects were novices in ARF but experts in programming. ARF
provides key contributions in the field of HIL testing of remote systems by providing more accessible
facilities that allow new or modified testing scenarios to be created where it might not have been
feasible to do so before. In turn this leads to early detection of faults which in some cases would not
have ever been detected before
The DEEP2 Galaxy Redshift Survey: Spectral classification of galaxies at z~1
We present a Principal Component Analysis (PCA)-based spectral
classification, eta, for the first 5600 galaxies observed in the DEEP2 Redshift
Survey. This parameter provides a very pronounced separation between absorption
and emission dominated galaxy spectra - corresponding to passively evolving and
actively star-forming galaxies in the survey respectively. In addition it is
shown that despite the high resolution of the observed spectra, this parameter
alone can be used to quite accurately reconstruct any given galaxy spectrum,
suggesting there are not many `degrees of freedom' in the observed spectra of
this galaxy population. It is argued that this form of classification, eta,
will be particularly valuable in making future comparisons between high and
low-redshift galaxy surveys for which very large spectroscopic samples are now
readily available, particularly when used in conjunction with high-resolution
spectral synthesis models which will be made public in the near future. We also
discuss the relative advantages of this approach to distant galaxy
classification compared to other methods such as colors and morphologies.
Finally, we compare the classification derived here with that adopted for the
2dF Galaxy Redshift Survey and in so doing show that the two systems are very
similar. This will be particularly useful in subsequent analyses when making
comparisons between results from each of these surveys to study evolution in
the galaxy populations and large-scale structure.Comment: 10 pages, 9 figures, Accepted for publication in Ap
Computer Microvision for Microelectromechanical Systems
Contains table of contents for Section 3 and reports on five research projects.Charles S. Draper Laboratory Contract DL-H-496015Defense Advanced Research Project Agency Grant F30602-97-2-0106W.M. Keck Foundation Career Development ProfessorshipAlfred P. Sloan Foundation Instrumentation Gran
The DEEP2 Galaxy Redshift Survey: Clustering of Galaxies in Early Data
We measure the two-point correlation function xi(r) using a sample of 2219
galaxies in an area of 0.32 degrees^2 at z=0.7-1.35 from the first season of
the DEEP2 Galaxy Redshift Survey. We find that xi(r) can be approximated by a
power-law, xi(r)=(r/r_0)^-gamma, on scales 0.1-20 Mpc/h. In a sample with an
effective redshift of z_eff=0.82, for a Lcdm cosmology we find r_0=3.53 +/-0.81
Mpc/h (comoving) and gamma=1.66 +/-0.12, while in a higher-redshift sample with
z_eff=1.14 we find r_0=3.14 +/-0.72 Mpc/h and gamma=1.61 +/-0.11. We find that
red, absorption-dominated, passively-evolving galaxies have a larger clustering
scale length, r_0, and more prominent ``fingers of God'' than blue,
emission-line, actively star-forming galaxies. Intrinsically brighter galaxies
also cluster more strongly than fainter galaxies at z~1, with a significant
luminosity-bias seen for galaxies fainter than M*. Our results are suggestive
of evolution in the galaxy clustering within our survey volume and imply that
the DEEP2 galaxies, with a median brightness one magnitude fainter than M* have
an effective bias b=0.97 +/-0.13 if sigma_{8 DM}=1 today or b=1.20 +/-0.16 if
sigma_{8 DM}=0.8 today. Given the strong luminosity-dependence in the bias that
we measure at z~1, the galaxy bias at M* may be significantly greater. We note
that our star-forming sample at z~1 has very similar selection criteria as the
Lyman-break galaxies at z~3 and that our red, absorption-line sample displays a
clustering strength comparable to the expected clustering of the Lyman-break
galaxy descendants at z~1. Our results demonstrate that the clustering
properties in the galaxy distribution seen in the local Universe were largely
in place by z~1.Comment: 17 pages, 8 figures, Revised version accepted by ApJ, minor changes
to text and figure
Ernst Freund as Precursor of the Rational Study of Corporate Law
Gindis, David, Ernst Freund as Precursor of the Rational Study of Corporate Law (October 27, 2017). Journal of Institutional Economics, Forthcoming. Available at SSRN: https://ssrn.com/abstract=2905547, doi: https://dx.doi.org/10.2139/ssrn.2905547The rise of large business corporations in the late 19th century compelled many American observers to admit that the nature of the corporation had yet to be understood. Published in this context, Ernst Freund's little-known The Legal Nature of Corporations (1897) was an original attempt to come to terms with a new legal and economic reality. But it can also be described, to paraphrase Oliver Wendell Holmes, as the earliest example of the rational study of corporate law. The paper shows that Freund had the intuitions of an institutional economist, and engaged in what today would be called comparative institutional analysis. Remarkably, his argument that the corporate form secures property against insider defection and against outsiders anticipated recent work on entity shielding and capital lock-in, and can be read as an early contribution to what today would be called the theory of the firm.Peer reviewe
Clinical Trials and Medical Care: Defining the Therapeutic Misconception
A key component of informed consent to participate in medical research includes understanding that research is not the same as treatment
A useful savagery: The invention of violence in nineteenth-century England
âA Useful Savagery: The Invention of Violence in Nineteenth-Century Englandâ considers a particular configuration of attitudes toward violence that emerged in the early decades of the nineteenth century. As part of a longer-term process of emerging âsensibilities,â violence was, seemingly paradoxically, âinventedâ as a social issue while concurrently relocated in the âcivilisedâ imagination as an anti-social feature mainly of âsavageâ working-class life. The dominant way this discourse evolved was through the creation of a narrative that defined âcivilisationâ in opposition to the presumed âsavageryâ of the working classes. Although the refined classes were often distanced from the physical experience of violence, concern with violence and brutality became significant parts of social commentary aimed at a middle-class readership. While stridently redefining themselves in opposition to âbrutality,â one of the purposes of this literature was to create a new middle class and justify the expansion of state power. By the closing decades of the nineteenth century, as the working classes adopted tenets of Victorian respectability, a proliferating number of social and psychological âothersâ were identified against which âcivilisedâ thought could define itself
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
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