Three-dimensional propagation effects: modeling, observations, suggested benchmark cases

Over the past several years, many acoustic propagation models have been adapted to compute the influence of azimuthal coupling. These so-called 3-D models should provide more accurate predictions of the acoustic field in 3-D variable environments than previous Nx2-D models. However, such advanced 3-D propagation models are generally slower than their Nx2-D predecessors. It is, therefore, important to understand the significance of the difference between 3-D and Nx2-D and when such effects should be considered. Furthermore, as of this date, no formal set of benchmark cases and solutions has been defined to test the accuracy of the various 3-D models currently being used. This paper will provide a general overview of 3-D propagation models and how they can be used to assess the significance of azimuthal coupling in ocean acoustics. Specific examples of such influences will be provided from a 3-D parabolic equation model and compared to results from the corresponding Nx2-D version. Of particular interest will be the pseudo-3-D effects predicted by Nx2-D calculations and the ability to distinguish true 3-D effects in experimental data. Finally, several environmental scenarios will be suggested as possible benchmark cases for future studies

Optimization of Complex Systems in the Presence of Uncertainty and Approximations

Engineering decisions are invariably made under substantial uncertainty about current and future system cost and response, including cost and response associated with low-probability but high-consequence events. Such events motivate approaches that typically have centered on constraining or minimizing probability of failure, in contrast to the risk-neutral approach of constraining or minimizing expected values. The research under this proposal has, instead, developed concepts of risk-averse decision making between these extremes with the aim of achieving an advanced methodology better able to deal with risks and reliability in engineering design. Measures of risk that go beyond statistical quantiles to so-called superquantiles (CVaR) and their mixtures have been the main focus. The results have explored their superior properties and enhanced computability along with surprising implications that standard least-squares regression in statistical approximations might better be supplanted by generalizations like quantile and even superquantile regression. Superquantile regression, which provides a cautious and powerful tool, is completely new. It is entirely a product of this grant research.The research was a collaborative effort with Johannes Royset of the Naval Postgraduate School, who had separate funding from AFOSR.Air Force Office of Science and ResearchDistribution A - Approved for public releas

Interhemispheric claustral circuits coordinate sensory and motor cortical areas that regulate exploratory behaviors

The claustrum has a role in the interhemispheric transfer of certain types of sensorimotor information. Whereas the whisker region in rat motor (M1) cortex sends dense projections to the contralateral claustrum, the M1 forelimb representation does not. The claustrum sends strong ipsilateral projections to the whisker regions in M1 and somatosensory (S1) cortex, but its projections to the forelimb cortical areas are weak. These distinctions suggest that one function of the M1 projections to the contralateral claustrum is to coordinate the cortical areas that regulate peripheral sensor movements during behaviors that depend on bilateral sensory acquisition. If this hypothesis is true, then similar interhemispheric circuits should interconnect the frontal eye fields (FEF) with the contralateral claustrum and its network of projections to vision-related cortical areas. To test this hypothesis, anterograde and retrograde tracers were placed in physiologically-defined parts of the FEF and primary visual cortex (V1) in rats. We observed dense FEF projections to the contralateral claustrum that terminated in the midst of claustral neurons that project to both FEF and V1. While the FEF inputs to the claustrum come predominantly from the contralateral hemisphere, the claustral projections to FEF and V1 are primarily ipsilateral. Detailed comparison of the present results with our previous studies on somatomotor claustral circuitry revealed a well-defined functional topography in which the ventral claustrum is connected with visuomotor cortical areas and the dorsal regions are connected with somatomotor areas. These results suggest that subregions within the claustrum play a critical role in coordinating the cortical areas that regulate the acquisition of modality-specific sensory information during exploration and other behaviors that require sensory attention

Reciprocity relationships in vector acoustics and their application to vector field calculations

The article of record as published may be found at 10.1121/1.4996458The reciprocity equation commonly stated in underwater acoustics relates pressure fields and monopole sources. It is often used to predict the pressure measured by a hydrophone for multiple source locations by placing a source at the hydrophone location and calculating the field everywhere for that source. A similar equation that governs the orthogonal components of the particle velocity field is needed to enable this computational method to be used for acoustic vector sensors. This paper derives a general reciprocity equation that accounts for both monopole and dipole sources. This vector-scalar reciprocity equation can be used to calculate individual components of the received vector field by altering the source type used in the propagation calculation. This enables a propagation model to calculate the received vector field components for an arbitrary number of source locations with a single model run for each vector field component instead of requiring one model run for each source location. Application of the vector-scalar reciprocity principle is demonstrated with analytic solutions for a range-independent environment and with numerical solutions for a range-dependent environment using a parabolic equation model

Physiological Arousal and Self-Reported Valence for Erotica Images Correlate with Sexual Policy Preferences

Individuals do not always accurately report the forces driving their policy preferences. Such inaccuracy may result from the fact that true justifications are socially undesirable or less persuasive than competing justifications or are unavailable in conscious awareness. Because of the delicate nature of these issues, people may be particularly likely to misstate the reasons for preferences on gay marriage, abortion, abstinence-only education, and premarital sex. Advocates on both sides typically justify their preferences in terms of preserving social order, maintaining moral values, or protecting civil liberties, not in terms of their own sexual preferences. Though these are the stated reasons, in empirical tests we find that psychophysiological response to sexual images also may be a significant driver of policy attitudes.This work was supported by the National Science Foundation [BCS-0826828]

An Examination of 3D, Broadband Acoustic Propagation Physics in a Littoral Ocean Environment - an Extension to an ONR Primer Field Study in the Mid-Atlantic Bight

0001497WR3000

3D Propagation and Geoacoustic Inversion Studies in the Mid-Atlantic Bight

Under the Shelf-Break Primer initiative, the Office of Naval Research sponsored a multi-year study of acoustic propagation in the region of the North Atlantic Bight off the coast of New Jersey. This region is of interest due to the combination of sloping bathymetry near the continental shelf and the strong oceanographic frontal features associated with the Gulf Stream. The general purpose of this project is to study the effects of the frontal region on acoustic propagation onto the shelf. Proposed here is a complementary study of propagation effects and data analysis. Specifically, the influence of three-dimensional propagation effects and their influence on the prediction of broadband measurements in similar oceanographic regions shall be addressed. Studies of two-dimensional propagation of broadband, explosive SUS will also be performed to examine correlations between geoacoustic properties and measured transmission loss. Results from this analysis will be considered in the context of geoacoustic inversions.N0001499WR3012

Genetic Attributions: Sign of Intolerance or Acceptance?

Many scholars argue that people who attribute human characteristics to genetic causes also tend to hold politically and socially problematic attitudes. More specifically, public acceptance of genetic influences is believed to be associated with intolerance, prejudice, and the legitimation of social inequities and laissez-faire policies. We test these expectations with original data from two nationally representative samples that allow us to identify the American public’s attributional patterns across 18 diverse traits. Key findings are (1) genetic attributions are actually more likely to be made by liberals, not conservatives; (2) genetic attributions are associated with higher, not lower, levels of tolerance of vulnerable individuals; and (3) genetic attributions do not correlate with unseemly racial attitudes