2,919 research outputs found
The strong K\"unneth theorem for topological periodic cyclic homology
Topological periodic cyclic homology (i.e., -Tate of ) has
the structure of a strong symmetric monoidal functor of smooth and proper dg
categories over a perfect field of finite characteristic
Algebraic K-theory and abstract homotopy theory
We decompose the K-theory space of a Waldhausen category in terms of its
Dwyer-Kan simplicial localization. This leads to a criterion for functors to
induce equivalences of K-theory spectra that generalizes and explains many of
the criteria appearing in the literature. We show that under mild hypotheses, a
weakly exact functor that induces an equivalence of homotopy categories induces
an equivalence of K-theory spectra.Comment: Final versio
Condition sensor system and method
The condition sensor system comprises a condition detector which produces a pulse when a parameter of the monitored condition exceeds a desired threshold. A resettable condition counter counts each pulse. A resettable timer is preset to produce a particular time frame. The counter produces a condition signal when the accumulated number of pulses within the time frame is equal to or greater than a preset count. Control means responsive to the incoming pulses and to the condition signal produce control signals that control utilization devices. After a suitable delay, the last detected pulse simultaneously resets the pulse counter and the timer, and prepares them for sensing another condition occurrence within the time frame. The invention has particular utility in the process of detecting rocking motions of blind people. A controlled, audible, bio-feedback signal is provided which constitutes a warning to the blind person that he is rocking
Mood, motility and 17-hydroxycorticoid excretion - a polyvariable case study
Mood, motility, and 17-hydroxycorticoid excretion in cyclic manic-depressive patien
Spacecraft-plasma interaction codes: NASCAP/GEO, NASCAP/LEO, POLAR, DynaPAC, and EPSAT
Development of a computer code to simulate interactions between the surfaces of a geometrically complex spacecraft and the space plasma environment involves: (1) defining the relevant physical phenomena and formulating them in appropriate levels of approximation; (2) defining a representation for the 3-D space external to the spacecraft and a means for defining the spacecraft surface geometry and embedding it in the surrounding space; (3) packaging the code so that it is easy and practical to use, interpret, and present the results; and (4) validating the code by continual comparison with theoretical models, ground test data, and spaceflight experiments. The physical content, geometrical capabilities, and application of five S-CUBED developed spacecraft plasma interaction codes are discussed. The NASA Charging Analyzer Program/geosynchronous earth orbit (NASCAP/GEO) is used to illustrate the role of electrostatic barrier formation in daylight spacecraft charging. NASCAP/low Earth orbit (LEO) applications to the CHARGE-2 and Space Power Experiment Aboard Rockets (SPEAR)-1 rocket payloads are shown. DynaPAC application to the SPEAR-2 rocket payloads is described. Environment Power System Analysis Tool (EPSAT) is illustrated by application to Tethered Satellite System 1 (TSS-1), SPEAR-3, and Sundance. A detailed description and application of the Potentials of Large Objects in the Auroral Region (POLAR) Code are presented
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