29,092 research outputs found
Analysis of aircraft spectrometer data with logarithmic residuals
Spectra from airborne systems must be analyzed in terms of their mineral-related absorption features. Methods for removing backgrounds and extracting these features one at a time from reflectance spectra are discussed. Methods for converting radiance spectra into a form similar to reflectance spectra so that the feature extraction procedures can be implemented on aircraft spectrometer data are also discussed
Synthetic aperture radar operator tactical target acquisition research
A radar target acquisition research study was conducted to access the effects of two levels of 13 radar sensor, display, and mission parameters on operator tactical target acquisition. A saturated fractional-factorial screening design was employed to examine these parameters. Data analysis computed ETA squared values for main and second-order effects for the variables tested. Ranking of the research parameters in terms of importance to system design revealed four variables (radar coverage, radar resolution/multiple looks, display resolution, and display size) accounted for 50 percent of the target acquisition probability variance
Understanding the nucleon as a Borromean bound-state
Analyses of the three valence-quark bound-state problem in relativistic
quantum field theory predict that the nucleon may be understood primarily as a
Borromean bound-state, in which binding arises mainly from two separate
effects. One originates in non-Abelian facets of QCD that are expressed in the
strong running coupling and generate confined but strongly-correlated
colour-antitriplet diquark clusters in both the scalar-isoscalar and
pseudovector-isotriplet channels. That attraction is magnified by quark
exchange associated with diquark breakup and reformation. Diquark clustering is
driven by the same mechanism which dynamically breaks chiral symmetry in the
Standard Model. It has numerous observable consequences, the complete
elucidation of which requires a framework that also simultaneously expresses
the running of the coupling and masses in the strong interaction. Planned
experiments are capable of validating this picture.Comment: 7 pages, 7 figure
The Dilemma of Direct Democracy
The dilemma of direct democracy is that voters may not always be able to make welfare- improving decisions. Lupia’s seminal work has led us to believe that voters can substitute voting cues for substantive policy knowledge. Lupia, however, emphasized that cues were valuable under certain conditions and not others. In what follows, we present three main findings regarding voters and what they know about California’s Proposition 7. First, much like Lupia reported, we show voters who are able to recall endorsements for or against a ballot measure vote similarly to people who recall certain basic facts about the initiative. We show, second, that voters whose stated policy preferences would otherwise suggest they would favor the “no” position cast their ballots with far less error than do people who favor the “yes” position. One thing this suggests is that many voters may employ a “defensive no” strategy when faced with complex policy choices on the ballot. Our third result is a bit surprising: we find that better- informed voters, whether this information is derived from factual knowledge of the initiative or from knowledge of well-publicized voting cues, are no more likely to make reasoned decisions than those who are, by our measure, uninformed. This suggests that existing theories of voter choice, especially in direct democracy, may be inadequate. We conclude with some preliminary policy recommendations that could help improve the information environment for initiatives and referenda by providing key information on the ballot
‘What happened to me does not define who I am’: Narratives of resilience in survivor victim impact statements
While research shows that “ideal victims” still receive more media coverage and more favorable depictions and results in the criminal justice system, it is not clear whether this is how victims of crime want to present themselves. We code and analyze the transcripts of 21 violence against women survivor victim impact statements (VIS) from YouTube videos, to assess how survivors present their victimization. While survivors of violence discuss their pain and trauma, they also call for better services and protection for other survivors, and attempt to bring awareness about the ubiquity of violence while motivating other survivors to come forward. Survivors rarely present themselves as stereotypically defined “ideal victims,” though in some cases, they do focus on their own blamelessness and the motherly, familial relationships that have been negatively impacted by their victimization. Though ideal victim presentation may be a rational response for those seeking justice from patriarchal legal institutions, survivors resist ideal victim presentations based on stereotypical notions of femininity, demonstrating that from their perspectives, hierarchies between “deserving” and “undeserving” victims may be dissipating
Ward-Green-Takahashi identities and the axial-vector vertex
The colour-singlet axial-vector vertex plays a pivotal role in understanding
dynamical chiral symmetry breaking and numerous hadronic weak interactions, yet
scant model-independent information is available. We therefore use longitudinal
and transverse Ward-Green-Takahashi (WGT) identities, together with kinematic
constraints, in order to ameliorate this situation and expose novel features of
the axial vertex: amongst them, Ward-like identities for elements in the
transverse piece of the vertex, which complement and shed new light on
identities determined previously for components in its longitudinal part. Such
algebraic results are verified via solutions of the Bethe-Salpeter equation for
the axial vertex obtained using two materially different kernels for the
relevant Dyson-Schwinger equations. The solutions also provide insights that
suggest a practical Ansatz for the axial-vector vertex.Comment: 7 pages, 3 figure
Nucleon spin structure at very high-x
Dyson-Schwinger equation treatments of the strong interaction show that the
presence and importance of nonpointlike diquark correlations within the nucleon
are a natural consequence of dynamical chiral symmetry breaking. Using this
foundation, we deduce a collection of simple formulae, expressed in terms of
diquark appearance and mixing probabilities, from which one may compute ratios
of longitudinal-spin-dependent u- and d-quark parton distribution functions on
the domain x =1. A comparison with predictions from other approaches plus a
consideration of extant and planned experiments shows that the measurement of
nucleon longitudinal spin asymmetries on x =1 can add considerably to our
capacity for discriminating between contemporary pictures of nucleon structure.Comment: 6 pages, 1 table, 3 figures. To appear in Phys. Lett.
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