4,302 research outputs found

    Generic Ada code in the NASA space station command, control and communications environment

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    The results of efforts to apply powerful Ada constructs to the formatted message handling process are described. The goal of these efforts was to extend the state-of-technology in message handling while at the same time producing production-quality, reusable code. The first effort was initiated in September, 1984 and delivered in April, 1985. That product, the Generic Message Handling Facility, met initial goals, was reused, and is available in the Ada Repository on ARPANET. However, it became apparent during its development that the initial approach to building a message handler template was not optimal. As a result of this initial effort, several alternate approaches were identified, and research is now on-going to identify an improved product. The ultimate goal is to be able to instantly build a message handling system for any message format given a specification of that message format. The problem lies in how to specify the message format, and one that is done, how to use that information to build the message handler. Message handling systems and message types are described. The initial efforts, its results and its shortcomings are detailed. The approach now being taken to build a system which will be significantly easier to implement, and once implemented, easier to use, is described. Finally, conclusions are offered

    High-temperature environments of human evolution in East Africa based on bond ordering in paleosol carbonates

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    Many important hominid-bearing fossil localities in East Africa are in regions that are extremely hot and dry. Although humans are well adapted to such conditions, it has been inferred that East African environments were cooler or more wooded during the Pliocene and Pleistocene when this region was a central stage of human evolution. Here we show that the Turkana Basin, Kenya—today one of the hottest places on Earth—has been continually hot during the past 4 million years. The distribution of ^(13)C-^(18)O bonds in paleosol carbonates indicates that soil temperatures during periods of carbonate formation were typically above 30 °C and often in excess of 35 °C. Similar soil temperatures are observed today in the Turkana Basin and reflect high air temperatures combined with solar heating of the soil surface. These results are specific to periods of soil carbonate formation, and we suggest that such periods composed a large fraction of integrated time in the Turkana Basin. If correct, this interpretation has implications for human thermophysiology and implies a long-standing human association with marginal environments

    Observations of perpetual hyphal propagation in Neurospora crassa

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    Observations of perpetual hyphal propagation in Neurospora crass

    Boundary effect of a partition in a quantum well

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    The paper wishes to demonstrate that, in quantum systems with boundaries, different boundary conditions can lead to remarkably different physical behaviour. Our seemingly innocent setting is a one dimensional potential well that is divided into two halves by a thin separating wall. The two half wells are populated by the same type and number of particles and are kept at the same temperature. The only difference is in the boundary condition imposed at the two sides of the separating wall, which is the Dirichlet condition from the left and the Neumann condition from the right. The resulting different energy spectra cause a difference in the quantum statistically emerging pressure on the two sides. The net force acting on the separating wall proves to be nonzero at any temperature and, after a weak decrease in the low temperature domain, to increase and diverge with a square-root-of-temperature asymptotics for high temperatures. These observations hold for both bosonic and fermionic type particles, but with quantitative differences. We work out several analytic approximations to explain these differences and the various aspects of the found unexpectedly complex picture.Comment: LaTeX (with iopart.cls, iopart10.clo and iopart12.clo), 28 pages, 17 figure

    Semicrompressible Ocean Thermodynamics and Boussinesq Energy Conservation

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    Equations more accurate than the Boussinesq set that still filter out sound were recently introduced. While these equations were shown to have a consistent potential energy, their thermodynamical behavior and associated implications were not fully analyzed. These shortcomings are remedied in the present note that argues both sets are fully consistent from a thermodynamic perspective. It is further argued that both sets remain computationally competitive with the Boussinesq set

    Anticipated impacts of voluntary assisted dying legislation on nursing practice

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    Background: The Voluntary Assisted Dying Act 2017 passed into law in Victoria, Australia, on the 29 November 2017. Internationally, nurses have been shown to be intimately involved in patient care throughout the voluntary assisted dying process. However, there is a paucity of research exploring Australian nurses’ perspectives on voluntary assisted dying and, in particular, how Victorian nurses anticipate the implementation of this ethically controversial legislation will impact their professional lives. Objectives: To explore Victorian nurses’ expectations of the ethical and practical impacts the voluntary assisted dying legislation will have on their professional lives. Research design: This qualitative study analysed nurses’ free text responses collected as part of a larger mixed methods online survey investigating staff views on the Voluntary Assisted Dying Act. Data were collected during the period between the passing of the voluntary assisted dying legislation and the start date and were analysed using inductive content analysis. Participants and research context: Free text survey responses were analysed from 1873 nurses employed across seven Victorian health services located in both metropolitan and regional areas of the state. Ethical considerations: The study obtained research ethics approval and all participants were informed of the voluntary and anonymous nature of their participation. Findings: This study identified three broad areas of Victorian nurses’ professional lives that they expected to be impacted by the implementation of voluntary assisted dying: professional identity, career development and workplace relationships. Conclusion: Participants anticipate diverse and nursing-specific impacts of the implementation of voluntary assisted dying in Victoria. Their insights can inform health services in jurisdictions considering or already implementing voluntary assisted dying, to develop policies, procedures and staff training programmes that safeguard the well-being and legal rights of their nursing staff

    The life and work of Nick Fofonoff

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    Author Posting. © Sears Foundation for Marine Research, 2005. This article is posted here by permission of Sears Foundation for Marine Research for personal use, not for redistribution. The definitive version was published in Journal of Marine Research 63 (2005): 1-7, doi:10.1357/0022240053693824
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