Shock Waves in Solid Craters

Shock waves in solid craters and effects of high speed impact of particles on space vehicle

Sex Education: The Parent's Perspective

Presents summary findings from the first in-depth statewide poll of California parents on school-based comprehensive sex education

Evolution of the Virtual Human: From Term to Potential Application in Psychiatry

Virtual reality applications in mental health have traditionally involved the creation of virtual environments that acted as provocative agents either for the purposes of the identification of disorders or their treatment. There is infrequent mention of the utilization of "virtual humans" despite the obvious significance of humans within our lives. More broadly, the term Virtual Human is frequently used in a number of contexts extending from its use as a term, modifying anything that needs to be modernized, to the application of 3D animated figures that exist in virtual realities. These applications refer to quite different phenomena in very different contexts leading to a high level of ambiguity and uncertainty when referring to virtual humans. In the following, the various applications of the term virtual human will be reviewed and critiqued through its most frequent applications, in various fields. They will be reviewed in an ascending manner from the least human of application to the most. Finally, a definition will be offered reflecting the potential complexity of the term as it reflects the expression of our most human factors, and how these are needed in the development of a model of a virtual human in psychiatry.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63235/1/10949310050078751.pd

SPREAD: Sound Propagation and Perception for Autonomous Agents in Dynamic Environments

The perception of sensory information and its impact on behavior is a fundamental component of being human. While visual perception is considered for navigation, collision, and behavior selection, the acoustic domain is relatively unexplored. Recent work in acoustics focuses on synthesizing sound in 3D environments; however, the perception of acoustic signals by a virtual agent is a useful and realistic adjunct to any behavior selection mechanism. In this paper, we present SPREAD, a novel agent-based sound perception model using a discretized sound packet representation with acoustic features including amplitude, frequency range, and duration. SPREAD simulates how sound packets are propagated, attenuated, and degraded as they traverse the virtual environment. Agents perceive and classify the sounds based on the locally-received packet set using a hierarchical clustering scheme, and have individualized hearing and understanding of their surroundings. Using this model, we demonstrate several simulations that greatly enrich controls and outcomes

Smart Events and Primed Agents

We describe a new organization for virtual human responses to dynamically occurring events. In our approach behavioral responses are enumerated in the representation of the event itself. These Smart Events inform an agent of plausible actions to undertake. We additionally introduce the notion of agent priming, which is based on psychological concepts and further restricts and simplifies action choice. Priming facilitates multi-dimensional agents and in combination with Smart Events results in reasonable, contextual action selection without requiring complex reasoning engines or decision trees. This scheme burdens events with possible behavioral outcomes, reducing agent computation to evaluation of a case expression and (possibly) a probabilistic choice. We demonstrate this approach in a small group scenario of agents reacting to a fire emergency

The Temperature Evolution of the Spectral Peak in High Temperature Superconductors

Recent photoemission data in the high temperature cuprate superconductor Bi2212 have been interpreted in terms of a sharp spectral peak with a temperature independent lifetime, whose weight strongly decreases upon heating. By a detailed analysis of the data, we are able to extract the temperature dependence of the electron self-energy, and demonstrate that this intepretation is misleading. Rather, the spectral peak loses its integrity above Tc due to a large reduction in the electron lifetime.Comment: 5 pages, revtex, 4 encapsulated postscript figure

Spectrally Resolved Flux Derived from Collocated AIRS and CERES Observations and its Application in Model Validation

Spectrally resolved outgoing IR flux, the integrand of the outgoing longwave radiation (OLR), has its unique value in evaluating model simulations. Here we describe an algorithm of deriving such clear-sky outgoing spectral flux through the whole IR region from the collocated Atmospheric Infrared Sounder (AIRS) and the Clouds & the Earth's Radiant Energy System (CERES) measurements over the tropical oceans. Based on the scene types and corresponding angular distribution models (ADMs) used in the CERES Single Satellite Footprint (SSF) dataset, spectrally-dependent ADMs are developed and used to estimate the spectral flux at each AIRS channel. A multivariate linear prediction scheme is then used to estimate spectral fluxes at frequencies not covered by the AIRS instrument. The whole algorithm is validated using synthetic spectra as well as the CERES OLR measurements. Using the GFDL AM2 model simulation as a case study, the application of the derived clear-sky outgoing spectral flux in model evaluation is illustrated. By comparing the observed and simulated spectral flux in 2004, compensating errors in the simulated OLR from different absorption bands can be revealed, so does the errors from frequencies within a given absorption band. Discrepancies between the simulated and observed spatial distributions and seasonal evolutions of the spectral fluxes at different spectral ranges are further discussed. The methodology described in this study can be applied to other surface types as well as cloudy-sky observations and corresponding model evaluations

Home Away from Home: Diaspora Tourism and Transnational Attachment of Second-Generation Chinese-Americans

Globalization has allowed contemporary immigrants to live in two worlds and maintain virtual and physical contact with their homeland through leisure and diaspora tourism. This study examined the lived experience of second-generation Chinese-Americans as they traveled to their parents’ country of origin and explored the relationship between their transnational homeland attachment and diaspora tourism experience. Using a phenomenological approach, twenty-six second-generation Chinese-Americans who had the experience of traveling in China were interviewed. Four themes were identified from their travel experience: destination image, authenticity, family history, and homeland attachment. Findings revealed how being a secondgeneration immigrant influenced the way they saw and experienced China as both destination and homeland