A NASTRAN/TREETOPS solution to a flexible, multi-body dynamics and controls problem on a UNIX workstation

Demands for nonlinear time history simulations of large, flexible multibody dynamic systems has created a need for efficient interfaces between finite-element modeling programs and time-history simulations. One such interface, TREEFLX, an interface between NASTRAN and TREETOPS, a nonlinear dynamics and controls time history simulation for multibody structures, is presented and demonstrated via example using the proposed Space Station Mobile Remote Manipulator System (MRMS). The ability to run all three programs (NASTRAN, TREEFLX and TREETOPS), in addition to other programs used for controller design and model reduction (such as DMATLAB and TREESEL, both described), under a UNIX Workstation environment demonstrates the flexibility engineers now have in designing, developing and testing control systems for dynamically complex systems

Fear in childbirth: are the media responsible?

This is the second year that the Centre for Midwifery, Maternal and Perinatal Health convened a debate as part of the Festival of Learning at Bournemouth University (BU). The debate encourages members of the public and service users to get involved in our research and education and ensures that what we do at BU is relevant and current. Last year the team debated the pros and cons of allowing women free choice with regard to major medical interventions, such as caesarean section (Hundley et al. 2013). This year the focus was on the role of the media in childbirth. Social perceptions and beliefs about childbirth can increase women’s requests for interventions, such as caesarean section, with long-term health implications for mothers and babies. The debate was planned to explore the role of the mass media in shaping these beliefs and identify whether media portrayals are responsible for rising rates of intervention. Attendees were given the opportunity to voice their views and to vote for or against the motion. The motion for debate was: This house believes that: The media is responsible for creating fear in childbirth

Thermal stress response of General Purpose Heat Source (GPHS) aeroshell material

A thermal stress test was conducted to determine the ability of the GPHS aeroshell 3 D FWPF material to maintain physical integrity when exposed to a severe heat flux such as would occur from prompt reentry of GPHS modules. The test was performed in the Giant Planetary Facility at NASA's Ames Research Center. Good agreement was obtained between the theoretical and experimental results for both temperature and strain time histories. No physical damage was observed in the test specimen. These results provide initial corroboration both of the analysis techniques and that the GPHS reentry member will survive the reentry thermal stress levels expected

Degradation and reuse of radiative thermal protection system materials for the space shuttle

Three silicide coated columbium alloys and two cobalt alloys were subjected to identical simulated reentry profiling exposures in both static (controlled vacuum leak) and dynamic (hypersonic plasma shear) environments. Primary emphasis in the columbium alloy evaluation was on the Cb752 and C129Y alloys with a lesser amount on FS85. Commercial silicide coatings of the R512E and VH109 formulations were used. The coated specimens were intentionally defected to provide the types of coating flaws that are expected in service. Temperatures were profiled up to peak temperatures of either 2350 F or 2500 F for 15 minutes in each cycle

Quality of life of adolescents with type 1 diabetes

INTRODUCTION: Diabetes mellitus is a highly prevalent chronic disease. Type 1 diabetes mellitus usually develops during infancy and adolescence and may affect the quality of life of adolescents. OBJECTIVE: To evaluate the quality of life of adolescents with type 1 diabetes mellitus in a metropolitan region of western central Brazil. METHODS: Adolescents aged 10-19 years who had been diagnosed with type 1 diabetes mellitus at least 1 year previously were included. Patients with verbal communication difficulties, severe disease, and symptomatic hypo- or hyperglycemic crisis as well as those without an adult companion and who were ;7%. In general, the adolescents consistently reported having a good quality of life. The median scores for the domains of the instrument were as follows: “satisfaction”: 35; “impact”: 51; and “worries“: 26. The total score for all domains was 112. Bivariate analysis showed significant associations among a lower family income, public health assistance, and insulin type in the “satisfaction” domain; and a lower family income, public health assistance, public school attendance, and a low parental education level in the “worries“ domain and for the total score. A longer time since diagnosis was associated with a lower total score. Multivariable analysis confirmed the association of a worse quality of life with public health assistance, time since diagnosis, and sedentary lifestyle in the “satisfaction” domain; female gender in the “worries” domain; and public health assistance for the total score. CONCLUSIONS: Overall, the adolescents evaluated in this study viewed their quality of life as good. Specific factors that led to the deterioration of quality of life, including public assistance, time since diagnosis, sedentary lifestyle, and female gender, were identified. No potential conflict of interest was reported

The quick and the dead: when reaction beats intention

Everyday behaviour involves a trade-off between planned actions and reaction to environmental events.Evidence from neurophysiology, neurology and functional brain imaging suggests different neural bases for the control of different movement types. Here we develop a behavioural paradigm to test movement dynamics for intentional versus reaction movements and provide evidence for a ‘reactive advantage’ in movement execution, whereby the same action is executed faster in reaction to an opponent. We placed pairs of participants in competition with each other to make a series of button presses. Within subject analysis of movement times revealed a 10 per cent benefit for reactive actions. This was maintained when opponents performed dissimilar actions, and when participants competed against a computer, suggesting that the effect is not related to facilitation produced by action observation. Rather, faster ballistic movements may be a general property of reactive motor control, potentially providing a useful means of promoting survival

Nash bargaining in ordinal environments

We analyze the implications of Nash’s (1950) axioms in ordinal bargaining environments; there, the scale invariance axiom needs to be strenghtened to take into account all order-preserving transformations of the agents’ utilities. This axiom, called ordinal invariance, is a very demanding one. For two-agents, it is violated by every strongly individually rational bargaining rule. In general, no ordinally invariant bargaining rule satisfies the other three axioms of Nash. Parallel to Roth (1977), we introduce a weaker independence of irrelevant alternatives axiom that we argue is better suited for ordinally invariant bargaining rules. We show that the three-agent Shapley-Shubik bargaining rule uniquely satisfies ordinal invariance, Pareto optimality, symmetry, and this weaker independence of irrelevant alternatives axiom. We also analyze the implications of other independence axioms

Robots and Cultural Heritage: New Museum Experiences

The introduction of new technologies to enhance the visiting museum experience is not a novelty. A large variety of interactive systems are nowadays available, including virtual tours, which makes cultural heritage accessible remotely. The theme of increase in accessibility and attractiveness has lately been faced with the employment of the service robotics, covering various types of applications. Regrettably, many of robotics solutions appear less successful in terms of utility and usability. On the basis of this awareness, a design for a new robotic solution for cultural heritage has been proposed. The project, developed at the royal residence of Racconigi Castle, consists of a telepresence robot designed as a tool to explore inaccessible areas of the heritage. The employed robot, called Virgil, was expressly designed for the project. The control of the robot is entrusted to the museum guides in order to enhance their work and enrich the cultural storytelling

Evaluating a model of global psychophysical judgments for brightness: II. Behavioral properties linking summations and productions

Steingrimsson (Attention, Perception, & Psychophysics, 71, 1916–1930, 2009) outlined Luce’s (Psychological Review, 109, 520–532 2002, 111, 446–454 2004) proposed psychophysical theory and tested, for brightness, behavioral properties that, separately, gave rise to two psychophysical functions, Ψ⊕ and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\Psi_{{ \circ_p}}}$$\end{document}. The function Ψ⊕ maps pairs of physical intensities onto positive real numbers and represents subjective summation, and the function \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\Psi_{{ \circ_p}}}$$\end{document} represents a form of ratio production. This article, the second in a series expected to consist of three articles, tests the properties linking summation and production such that it forces \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\Psi_{{ \circ_p}}} = {\Psi_\oplus } = \Psi$$\end{document}. The properties tested are a form of distributivity and, in three experiments, were subjected to an empirical evaluation. Considerable support is provided for the existence of a single function Ψ for both summation and ratio production. The scope of this series of articles is to establish the theory as a descriptive model of binocular brightness perception