116,778 research outputs found

    On the Measure in Simplicial Gravity

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    Functional measures for lattice quantum gravity should agree with their continuum counterparts in the weak field, low momentum limit. After showing that the standard simplicial measure satisfies the above requirement, we prove that a class of recently proposed non-local measures for lattice gravity do not satisfy such a criterion, already to lowest order in the weak field expansion. We argue therefore that the latter cannot represent acceptable discrete functional measures for simplicial geometries.Comment: LaTeX, 15 pages, 2 figure

    Silver-base ternary alloy proves superior for slip ring lead wires

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    Slip ring lead wires composed of ternary alloys of silver, have high electrical conductivity, a tensile strength of at least 30,000 psi, high ductility, and are solderable and weldable. An unexpected advantage of these alloys is their resistance to discoloration on heating in air

    An investigation of volcanic depressions. Part 1: Airfall and intrusive pyroclastic deposits. Part 2: Subaerial pyroclastic flows and their deposits

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    Pyroclastic ejecta and the deposits they form were classified in many ways, and many interpretations were given to individual terms. Some classifications are based on the modes of orgin and deposition of the ejecta; others emphasized the chemical and physical composition of the ejecta. Particle-size was used as the prime basis of subdivision, and the same size-limits were used as those employed in the classification of sediments and sedimentary rocks

    Extended plasticity in commercial-purity zinc

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    90% rolling-reduction of annealed commercial-purity zinc sheet (grain size 100 - 150 μ) results in the fragmentation of the large grains into, finally, stable micro-grains, 1 - 211 in diameter. The stability of the micro-grains is due to the presence of soluble and insoluble impurities which prevent recrystallization. This micro-grain material is strain-rate sensitive, and elongations of 200% have been obtained at room temperature. Although this as-rolled, 90% reduction zinc sheet is not super-plastic according to the current definition, its behaviour has led to the coining of the phase 'extended plasticity'. Evidence of grain-boundary sliding is found on examination of the surface by scanning electron microscopy, while the examination of thin foils and activation energy measurements support the dynamic softening (recovery) theory; thus, both these mechanisms must be operating, to a greater or less extent, to confer on this material the observe mechanical behaviour. It is finally concluded that it is dangerous to draw conclusions regarding the mechanism of plastic deformation from surface observations alone

    Preliminary geologic mapping near the Nilosyrtis Mensae, Mars

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    Virtually the entire map area is mantled by an irregular deposit of material that is apparently fine-grained and erodible. It is also extremely young, as there is not a single crater larger than 1 km in the map area that was emplaced atop the mantle. Knobs abound in the study area; many are presumably caused by the mantling of pre-existing topography. In many cases the older knob of the core is exposed. Many such knob cores are surrounded by small scarplets; it is not yet clear whether the scarplets are the eroded edges of mantle beds that at one time draped over the knob core and have been subsequently exposed by erosion, or whether they are eroded versions of lobate debris aprons. Many craters in the study area contain concentric crater fill, which may indicate downslope movement of volatile-rich materials or repeated cycles of aeolian gradation

    An investigation of volcanic depressions. Part 1 - Geologic and geophysical features of calderas Progress report

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    Preferred classification of calderas and volcano- tectonic depressions based on relative amounts of lava and proclastic eject

    Low speed testing of the inlets designed for a tamden-fan V/STOL nacelle

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    An approximately 0.25 scale model of a tandem fan nacelle, designed for a subsonic V/STOL aircraft, was tested in a Lewis wind tunnel. Model variables included long and short aft inlet cowls and the addition of exterior strakes to the short inlet cowl. Inlet pressure recoveries and distortion were measured at pitch angles to 40 deg and at combinations of pitch and yaw to 30 deg. Airspeeds covered a range to 135 knots (69 m/sec). The short aft inlet with added strakes had the best aerodynamic performance and is considered suitable for the intended V/STOL application

    Geologic mapping of MTM quads 40292 and 40297: In the Utopian lowlands north of the Nilosyrtis Mensae, Mars

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    Geologic mapping at 1:500,000 scale of the Mars transverse Mercator (MTM) quads 40292 and 40297 is being conducted under the auspices of the Mars Geologic Mapping Program. The study area is located in the southwestern portion of Utopia Planitia immediately north of the Nilosyrtis Mensae, between latitudes 37.5 and 42.5 degrees and longitudes 290 and 300 degrees. The goals of the mapping are to identify the major geologic features in the study area and to determine the sequence and scope of the geologic events that have modified the lowland side of the global dichotomy boundary in this region in order to at least partially constrain models of dichotomy boundary origin and evolution. The progress made towards achieving these goals is reported

    Using Gaussian Processes to Optimise Concession in Complex Negotiations against Unknown Opponents

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    In multi-issue automated negotiation against unknown opponents, a key part of effective negotiation is the choice of concession strategy. In this paper, we develop a principled concession strategy, based on Gaussian processes predicting the opponent's future behaviour. We then use this to set the agent's concession rate dynamically during a single negotiation session. We analyse the performance of our strategy and show that it outperforms the state-of-the-art negotiating agents from the 2010 Automated Negotiating Agents Competition, in both a tournament setting and in self-play, across a variety of negotiation domains

    Interconnectivity and Metacommunication

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    The study of interpersonal communication touches on a range of different disciplines, each with their own focus. This has given rise to an apparent fragmentation in the literature (O’Keefe, 1993; Craig 1999, Stephen 2014) which is manifested in the categorisation of the various components of a communicative act and even the subdivision of the categories established. This can be seen in the study of metacommunication, which although considered an essential component of human interaction (Andersen, 2009; Wilmot, 1980) has been subdivided into a myriad of constituent parts. Whilst the separation of various components permits detailed focus on different facets of interpersonal interaction there is a risk that the complementarity of the various facets may be underestimated or even lost. Indeed to autonomise each aspect of a communicative act may not be conducive to a comprehensive understanding of what happens in an interaction since all elements, verbal, non-verbal and contextual, to name but a few, need to be considered and interpreted simultaneously. Approaches to the study of metacommunication, whilst being multidimensional, appear to have led to fragmentation. It is our contention that understanding of what constitutes a complete communicative interaction involves the consideration of these various aspects at the same time. Starting from the position that no category exists in a vacuum, and is part and parcel of a whole communicative act, this article draws on Wilmot’s seminal (1980) article among others and considers a more holistic approach to communication as an adjunct to the current tendency for separation. To illustrate this method, the article identifies various aspects and categories within the area of metacommunication and examines the convergence and potential divergence within them. Through the case study of silence as a communicative act that appears to bridge various sub-divisions , this paper argues for an umbrella conceptualisation that unifies rather than compartmentalises the various aspects of metacommunication
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