33 research outputs found

    Black Hole Thermodynamics and Statistical Mechanics

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    We have known for more than thirty years that black holes behave as thermodynamic systems, radiating as black bodies with characteristic temperatures and entropies. This behavior is not only interesting in its own right; it could also, through a statistical mechanical description, cast light on some of the deep problems of quantizing gravity. In these lectures, I review what we currently know about black hole thermodynamics and statistical mechanics, suggest a rather speculative "universal" characterization of the underlying states, and describe some key open questions.Comment: 35 pages, Springer macros; for the Proceedings of the 4th Aegean Summer School on Black Hole

    Alkane Profiles in Tropical Forages

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    The role of n-alkanes in animal nutrition research has recently been reviewed by Dove and Mayes (1996). The measurement of voluntary intake (VI) using the naturally occurring odd chain length alkanes C31 or C33 in conjunction with administered even chain length alkanes such as C32 and C36 provides several advantages over the more conventional methods. Much of the development work involving this technology has been carried out with sheep or dairy cattle fed predominantly temperate pasture. Laredo et al., (1991) have published alkane profiles for a number of introduced tropical pasture grasses but no alkane profiles have been published for native tropical pasture grasses. Animal production for a consuming world : proceedings of 9th Congress of the Asian-Australasian Association of Animal Production Societies [AAAP] and 23rd Biennial Conference of the Australian Society of Animal Production [ASAP] and 17th Annual Symposium of the University of Sydney, Dairy Research Foundation, [DRF]. 2-7 July 2000, Sydney, Australia

    Using Alkanes to Predict Voluntary Intake, Faecal Output and Digestibility of Buffel Grass Hay Fed to Steers

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    The cuticular waxes of forage plants contain long chain n-alkanes with odd carbon chain lengths in the range C25-C37 which are quantitatively recovered in faeces. When these concentrations are used with the concentrations of administered synthetic even chain length alkanes, the voluntary intake (VI), faecal output (FO) and digestibility (DMD) of forages can be estimated (Dove and Mayes 1991, 1996)

    Modeling and simulation of a blood pump for the development of a left ventricular assist system controller

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    summary:A mathematical model describing the pressure-volume relationship of the Novacor left ventricular assist system (LVAS) was developed. The model consisted of lumped resistance, capacitance, and inductance elements with one time-varying capacitor to simulate the cyclical pressure generation of the system. The ejection and filling portions of the pump cycle were modeled with two separate functions. The corresponding model parameters were estimated by least squares fit to experimental data obtained in the laboratory. The model performed well at simulating pump pressure of operation throughout the full cycle. Computer simulation of the pump with a cardiovascular model demonstrated the interaction between the LVAS and the cardiovascular system. This model can be used to incorporate on-line cardiovascular parameter estimation and to design a new controller for the LVAS
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