Research on an expert system for database operation of simulation-emulation math models. Volume 1, Phase 1: Results

The results of the first phase of Research on an Expert System for Database Operation of Simulation/Emulation Math Models, is described. Techniques from artificial intelligence (AI) were to bear on task domains of interest to NASA Marshall Space Flight Center. One such domain is simulation of spacecraft attitude control systems. Two related software systems were developed to and delivered to NASA. One was a generic simulation model for spacecraft attitude control, written in FORTRAN. The second was an expert system which understands the usage of a class of spacecraft attitude control simulation software and can assist the user in running the software. This NASA Expert Simulation System (NESS), written in LISP, contains general knowledge about digital simulation, specific knowledge about the simulation software, and self knowledge

Research on an expert system for database operation of simulation-emulation math models. Volume 2, Phase 1: Results

A reference manual is provided for NESS, a simulation expert system. This manual gives user information regarding starting and operating NASA expert simulation system (NESS). This expert system provides an intelligent interface to a generic simulation program for spacecraft attitude control problems. A menu of the functions the system can perform is provided. Control repeated returns to this menu after executing each user request

Can gender categorization influence the perception of animated virtual humans?

Animations have become increasingly realistic with the evolution of Computer Graphics (CG). In particular, human models and behaviors were represented through animated virtual humans, sometimes with a high level of realism. In particular, gender is a characteristic that is related to human identification, so that virtual humans assigned to a specific gender have, in general, stereotyped representations through movements, clothes, hair and colors, in order to be understood by users as desired by designers. An important area of study is finding out whether participants' perceptions change depending on how a virtual human is visually presented. Findings in this area can help the industry to guide the modeling and animation of virtual humans to deliver the expected impact to the audience. In this paper, we reproduce, through CG, a perceptual study that aims to assess gender bias in relation to a simulated baby. In the original study, two groups of people watched the same video of a baby reacting to the same stimuli, but one group was told the baby was female and the other group was told the same baby was male, producing different perceptions. The results of our study with virtual babies were similar to the findings with real babies. First, it shows that people's emotional response change depending on the character gender attribute, in this case the only difference was the baby's name. Our research indicates that by just informing the name of a virtual human can be enough to create a gender perception that impact the participant emotional answer.Comment: 8 pages, 1 figure, 2 table

Advancing Torpor Inducing Transfer Habitats for Human Stasis to Mars

SpaceWorks Enterprises, Inc. (SEI) has conducted an evaluation of an advanced habitat system designed to transportcrews between the Earth and Mars. This new and innovative habitat concept is capable of placing crew members ininactive, torpor states during transit phases of a deep space mission. This substantially reduces the mass and size ofthe habitat, which ultimately leads to significant reductions in the overall architecture size.Our approach for achieving this is based on extending the current and evolving medical practice of TherapeuticHypothermia (TH) - a proven and effective treatment for various traumatic injuries. TH is a medical treatment thatlowers a patient's body temperature by just 5 to 10 degrees Fahrenheit causing human metabolic rate to decreasesignificantly and the body to enter an unconscious state. This method avoids the intractable challenges often associatedwith cell metabolic cessation through cryogenic freezing and other highly speculative approaches.The initial results obtained from the research and analysis conducted in the Phase I effort warranted further study ofthis concept and technology. The specific objectives of the continued work include:1. Addressing critical medical aspects and risks for inducing torpor via Therapeutic Hypothermia and theapproach for providing nutrition and hydration for the crew during torpor. 2. Focusing on mitigation aspects and technology potential for solving key human spaceflight challenges. 3. Addressing critical engineering aspects of the design that may impact the initial performance and cost resultsobtained in Phase I. 4. Examining the broader extensibility and enabling capabilities of this concept through applicability toadditional exploration missions beyond Mars. 5. Establishing a technology development roadmap, addressing both medical and engineering aspects, thatindicate a logical and scientifically achievable path forward for maturation of this technology

Mass modification of D-meson in hot hadronic matter

We evaluate the in-medium $D$ and $\bar D$-meson masses in hot hadronic matter induced by interactions with the light hadron sector described in a chiral SU(3) model. The effective Lagrangian approach is generalized to SU(4) to include charmed mesons. We find that the D-mass drops substantially at finite temperatures and densities, which open the channels of the decay of the charmonium states ($\Psi^\prime$, $\chi_c$, $J/\Psi$) to $D \bar D$ pairs in the thermal medium. The effects of vacuum polarisations from the baryon sector on the medium modification of the $D$-meson mass relative to those obtained in the mean field approximation are investigated. The results of the present work are compared to calculations based on the QCD sum-rule approach, the quark-meson coupling model, chiral perturbation theory, as well as to studies of quarkonium dissociation using heavy quark potential from lattice QCD.Comment: 18 pages including 7 figures, minor revision of the text, figure styles modified, to appear in Phys. Rev.

The association of road traffic noise with cognition in adolescents: a cohort study in Switzerland

Environmental noise exposure has been shown to affect children's cognition, but the concept of cognition is multifaceted, and studies on associations with noise are still inconclusive and fragmented. We studied cognitive change within one year in 882 adolescents aged 10-17 years in response to road traffic noise exposure. Participants filled in a comprehensive questionnaire and underwent cognitive testing twice at an interval of one year. Figural and verbal memory was measured with the Intelligenz-Struktur-Test (IST), and concentration accuracy and constancy were measured with FAKT-II and d2 test. Exposure to noise and other environmental stressors were modelled for school and home location at baseline. Missing data was addressed with multiple imputation. Cross-sectional multilevel analyses and longitudinal change score analyses were performed. In cross-sectional analyses, figural memory was significantly reduced by -0.27 (95%CI -0.49,-0.04) units per 10 dB road traffic noise increase at home (L(den)). Longitudinal analyses showed a significant reduction of concentration constancy Z-scores between baseline and follow-up by -0.13 (95%CI -0.25, 0.00) per 10 dB road traffic noise at home (L(den)). Our study indicates that road traffic noise at home reduces cognitive performance in adolescents. Larger cohorts with longer follow-up time are needed to confirm these results

Distortion in a 7xxx aluminum alloy during liquid phase sintering

The distortion in a sintered 7xxx aluminum alloy, Al-7Zn-2.5Mg-1Cu (wt. pct), has been investigated by sintering three rectangular bars in each batch at 893 K (620 °C) for 0 to 40 minutes in nitrogen, followed by air or furnace cooling. They were placed parallel to each other, equally spaced apart at 2 mm, with their long axes being perpendicular to the incoming nitrogen flow. Pore evolution in each sample during isothermal sintering was examined metallographically. The compositional changes across sample mid-cross section and surface layers were analyzed using energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy depth profiling, respectively. The two outer samples bent toward the middle one, while the middle sample was essentially distortion free after sintering. The distortion in the outer samples was a result of differential shrinkage between their outer and inner surfaces during isothermal sintering. The porous outer surface showed an enrichment of oxygen around the large pores as well as lower magnesium and zinc contents than the interior and inner surface of the same sample, while the inner surface was distinguished by the presence of AlN. The differential shrinkage was caused by different oxygen contents in local sintering atmosphere and unbalanced loss of magnesium and zinc between the outer and inner surfaces

Binder-treated segregation-free aluminum alloy powders

Two paraffin waxes with different melting points and mixed at a specific mass ratio were used as a binder for premixed aluminum alloy powders. Dusting, segregation, and part-to-part variability were significantly reduced and powder flow improved compared to untreated powder In addition, the green density of compacts fabricated from the binder-treated powders was higher than that of the untreated powders. Sintered mechanical properties were not significantly affected by the addition of the binder Air-drying alkyd binders and water-based wax emulsions were also tested, but the results were less satisfactory