3,361 research outputs found

    Two fault tolerant toggle-hook release

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    A coupling device is disclosed which is mechanically two fault tolerant for release. The device comprises a fastener plate and fastener body, each of which is attachable to a different one of a pair of structures to be joined. The fastener plate and body are coupled by an elongate toggle mounted at one end in a socket on the fastener plate for universal pivotal movement thereon. The other end of the toggle is received in an opening in the fastener body and adapted for limited pivotal movement therein. The toggle is adapted to be restrained by three latch hooks arranged in symmetrical equiangular spacing about the axis of the toggle, each hook being mounted on the fastener body for pivotal movement between an unlatching non-contact position with respect to the toggle and a latching position in engagement with a latching surface of the toggle. The device includes releasable lock means for locking each latch hook in its latching position whereby the toggle couples the fastener plate to the fastener body and means for releasing the lock means to unlock each said latch hook from the latch position whereby the unlocking of at least one of the latch hooks from its latching position results in the decoupling of the fastener plate from the fastener body

    Scheduling Ocean Transportation of Crude Oil

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    Management Science, 33, p. 335-346. (Nominated for 1987 International Management Science Achievement Award.)The article of record as published may be found at http://links.jstor.org/sici?sici=0025-1909%28198703%2933%3A3%3C335%3ASOTOCO%3E2.0.CO%3B2-FNominated for 1987 International Management Science Achievement Award.A crude oil tankerscheduling problem faced by a major oil company is presented and solved using an elastic set partitioning model. The model takes into account all fleet cost components, including the opportunity cost of ship time, port and canal charges, and demurrage and bunker fuel. The model determines optimalspeeds for the ships and the best routing of ballast (empty) legs, as well as which cargos to load on controlled ships and which to spot charter. All feasible schedules are generated, the cost of each is accurately determined and the best set of schedules is selected. For the problems encountered, optimal integer solutions to set partitioning problems with thousands of binary variables have been achieved in less than a minute

    Toggle release

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    A pyrotechnic actuated structural release device 10 which is mechanically two fault tolerant for release. The device 10 comprises a fastener plate 11 and fastener body 12, each attachable to a different one of a pair of structures to be joined. The fastener plate 11 and body 12 are fastenable by a toggle 13 supported at one end on the fastener plate and mounted for universal pivotal movement thereon. At its other end which is received in a central opening in the fastener body 12 and adapted for limited pivotal movement therein the toggle 13 is restrained by three retractable latching pins 61 symmetrically disposed in equiangular spacing about the axis of the toggle 13 and positionable in latching engagement with an end fitting on the toggle. Each pin 61 is individually retractable by combustion of a pyrotechnic charge 77, the expanding gases of which are applied to a pressure receiving face 67 on the latch pin 61 to effect its retraction from the toggle. While retraction of all three pins 62 releases the toggle, the fastener is mechanically two fault tolerant since the failure of any single one or pair of the latch pins to retract results in an asymmetrical loading on the toggle and its pivotal movement to effect a release. An annular bolt 18 is mounted on the fastener plate 11 as a support for the socket mounting 30, 37 of the toggle whereby its selective axial movement provides a means for preloading the toggle

    Evidence of diet, deification, and death within ancient Egyptian mummified animals

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    The clues to life and death of mummified animals can remain hidden beneath their wrappings. Developments in non-invasive imaging have enabled detailed study of their internal structures. Laboratory-based X-ray microcomputed tomography (microCT) and focussed imaging protocols permit smaller mummified remains, such as animals, to be studied at higher resolution. In this study, we use microCT to image three different animal mummies. Revealing the internal structures provides insights into their biography, the conditions in which they were kept, complex mummification practices, possible causes of death, and subsequent handling damage. Thousands of years after the production of these mummified animals, the X-ray microCT technique facilitates new investigations, revealing ‘harder’ skeletal structures, mummification materials, and even desiccated soft tissues. Potential evidence for an ‘opening of the mouth’ procedure was found in a snake, along with indicators of the poor conditions in which the snake was kept when alive, leading to dehydration. Examination of a cat mummy revealed it was less than five months old and had its neck purposefully broken. It was also possible to identify a bird mummy to species level from the X-ray data. Improved understanding of animal mummification through scientific imaging can thus inform conservation and understanding of past human-animal relationships

    The ideological significance of flint in Dynastic Egypt

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    This thesis examines a little understood aspect of Dynastic Egypt—that of the ideology of flint. Ideology is defined as the way flint is thought of rather than used. This study is unique in examining long term chronological changes in flint ideology against the background of increased metal use, and in using together text, iconography, and archaeology: studies of Egyptian ideology traditionally privilege text. Metaphor theory is employed as an important tool to aid this study. While metaphor is frequently used in Egyptological studies of Egyptian religion, its use is rarely explicit. The dataset brings together unpublished artefacts in British museum collections; a first hand analysis of lithics from Panhesy’s house at Amarna; finds cards from recent excavations at Memphis; and textual sources, several of which have not been considered before in relation to the ideology of flint; as well as published data on Egyptian lithic material. Chronological changes in ideology surrounding flint during the Bronze and Iron Ages, a time of flint decline, are considered. Because the nature of flint decline in Egypt has been assumed rather than known, I attempt to quantify the process. Conclusions show that the ideology of flint was far from static but only loosely related to the kinetic decline of flint. Flint is shown to be connected with the goddesses who are the Eye of Re, with Re himself, with snakes and lions. New facets of flint ideology are uncovered, including the connection of the material with the northern sky and the link between the treatment of New Kingdom Theban flint concretions and the religious landscape of the area

    Relationship Between Perceptions of Family Life and Attitudes Concerning Father-Son Interaction

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    Family Relations and Child Developmen

    Automated Morphological Classification of SDSS Red Sequence Galaxies

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    (abridged) In the last decade, the advent of enormous galaxy surveys has motivated the development of automated morphological classification schemes to deal with large data volumes. Existing automated schemes can successfully distinguish between early and late type galaxies and identify merger candidates, but are inadequate for studying detailed morphologies of red sequence galaxies. To fill this need, we present a new automated classification scheme that focuses on making finer distinctions between early types roughly corresponding to Hubble types E, S0, and Sa. We visually classify a sample of 984 non-starforming SDSS galaxies with apparent sizes >14". We then develop an automated method to closely reproduce the visual classifications, which both provides a check on the visual results and makes it possible to extend morphological analysis to much larger samples. We visually classify the galaxies into three bulge classes (BC) by the shape of the light profile in the outer regions: discs have sharp edges and bulges do not, while some galaxies are intermediate. We separately identify galaxies with features: spiral arms, bars, clumps, rings, and dust. We find general agreement between BC and the bulge fraction B/T measured by the galaxy modeling package GIM2D, but many visual discs have B/T>0.5. Three additional automated parameters -- smoothness, axis ratio, and concentration -- can identify many of these high-B/T discs to yield automated classifications that agree ~70% with the visual classifications (>90% within one BC). Both methods are used to study the bulge vs. disc frequency as a function of four measures of galaxy 'size': luminosity, stellar mass, velocity dispersion, and radius. All size indicators show a fall in disc fraction and a rise in bulge fraction among larger galaxies.Comment: 24 pages, 20 figures, MNRAS accepte

    Distributions of eight meteorological variables at Cape Kennedy, Florida and Vandenberg Air Force Base, California

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    Extreme values, median values, and nine percentile values are tabulated for eight meteorological variables at Cape Kennedy, Florida and at Vandenberg Air Force Base, California. The variables are temperature, relative humidity, station pressure, water vapor pressure, water vapor mixing ratio, density, and enthalpy. For each month eight hours are tabulated, namely, 0100, 0400, 0700, 1000, 1300, 1600, 1900, and 2200 local time. These statistics are intended for general use for the space shuttle design trade-off analysis and are not to be used for specific design values
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