21,467 research outputs found

    Review of measured vibration and noise environments experienced by passengers in aircraft and in ground transportation systems

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    Measured vibration and interior noise data are presented for a number of air and surface vehicles. Consideration is given to the importance of direction effects; of vehicle operations such as take-off, cruise, and landing; and of measurement location on the level and frequency of the measurements. Various physical measurement units or descriptors are used to quantify and compare the data. Results suggest the range of vibration and noise associated with a particular mode of transportation and illustrate the comparative levels in terms of each of the descriptors. Collectively, the results form a data base which may be useful in assessing the ride of existing or future systems relative to vehicles in current operation

    Kissing numbers and transference theorems from generalized tail bounds

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    We generalize Banaszczyk's seminal tail bound for the Gaussian mass of a lattice to a wide class of test functions. From this we obtain quite general transference bounds, as well as bounds on the number of lattice points contained in certain bodies. As applications, we bound the lattice kissing number in p\ell_p norms by e(n+o(n))/pe^{(n+ o(n))/p} for 0<p20 < p \leq 2, and also give a proof of a new transference bound in the 1\ell_1 norm.Comment: Previous title: "Generalizations of Banaszczyk's transference theorems and tail bound

    Physical and subjective studies of aircraft interior noise and vibration

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    Measurements to define and quantify the interior noise and vibration stimuli of aircraft are reviewed as well as field and simulation studies to determine the subjective response to such stimuli, and theoretical and experimental studies to predict and control the interior environment. In addition, ride quality criteria/standards for noise, vibration, and combinations of these stimuli are discussed in relation to the helicopter cabin environment. Data on passenger response are presented to illustrate the effects of interior noise and vibration on speech intelligibility and comfort of crew and passengers. The interactive effects of noise with multifrequency and multiaxis vibration are illustrated by data from LaRC ride quality simulator. Constant comfort contours for various combinations of noise and vibration are presented and the incorporation of these results into a user-oriented model are discussed. With respect to aircraft interior noise and vibration control, ongoing studies to define the near-field noise, the transmission of noise through the structure, and the effectiveness of control treatments are described

    Flexible ring slosh damping baffle Patent

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    Flexible ring slosh damping baffle for spacecraft fuel tan

    Active vibration isolator for flexible bodies Patent

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    Vibration control of flexible bodies in steady accelerating environmen

    Improved active vibration isolator

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    Active vibration isolator simultaneously isolates a flexible structure or payload from disturbances, attenuates the response of a flexible structure to transient disturbances, and maintains the equilibrium position of the payload within predetermined limits over a wide range of steady loads and accelerators

    The Sulzer Hip Replacement Recall Crisis: A Patient\u27s Perspective

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    This case discusses a product recall that resulted from a manufacturing defect and the degree to which the company distributed accurate and timely information to affected patients. More specifically, the case examines the crisis communication of Sulzer Orthopedics and its efforts to negotiate the interests of various stakeholders, while limiting liability. Written from the perspective of a patient, the case raises interesting questions regarding organizational duties related to product liability. It also provides valuable insights into how organizational communication may have both short- and long-term effects on its relationship with patients and physicians, among others

    Automatic closed circuit television arc guidance control Patent

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    Automatic closed circuit television arc guidance control for welding joint

    Instrument for measuring the dynamic behavior of liquids Patent

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    Pressure sensor network for measuring liquid dynamic response in flight including fuel tank acceleration, liquid slosh amplitude, and fuel depth monitorin

    Health and sustainable development

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    If sustainable development is to mean anything, people must be healthy enough to benefit from it and not have their lives cut off prematurely. Development without health is meaningless. But the processes which are likely to occur in a world undergoing globalisation, climate change, urbanisation, population increase and many other changes, will impact upon human health in complex ways. Some of them will benefit us, others will create new or augmented threats to survival and health, while many others will have a complex mixture of effects
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