1,215 research outputs found
Noise limiter Patent
Circuits for amplitude limiting of random noise input
Control of acceleration in sine/random vibration tests
Sampling output levels of accelerometers using largest output or any combination of outputs provide control of shaker for spacecraft vibration qualification tests
Automatic Gaussian random-noise limiter
Circuit limits the positive and negative peaks of a random-noise signal. It accurately establishes a known limiting level relative to any given RMS value of the random-noise signal input
Gated compressor, distortionless signal limiter
Comparator/multiplier arrangement is capable of limiting input power to voice coil so that desired maximum current level is never exceeded. Overall test system consists of signal source which produces frequency spectrum required for acoustic test, gated compressor circuit, and power amplifier feeding transducer
Spectral analysis applied to a digitally coded PM RF carrier
Spectral analysis applied to digitally coded phase modulated radio frequency carrie
Apparatus for scanning the surface of a cylindrical body
A laser scanning system for providing a two-dimensional display of a cylindrical surface, such as to display striae of a fired bullet is described. The cylinder is scanned along its axis by vibrating one mirror in the laser beam path, and is scanned in a direction normal to its axis by vibrating a second mirror in a direction normal to the first or by rotating the bullet. Scan control signals are adjusted in phase to produce a synchronized display of a video signal obtained from detection of scattered light from the surface thus scanned by a laser beam
Digital decorrelator saves time and expense in acoustic testing of structures
Instantaneous signals from coherent random sound field are summed and time delayed to avoid introducing vectorial addition errors. Resultant statistically independent signals are applied to spectrometer. Displayed sound pressure level is proportional to square root of sum of squares of sound pressure levels taken over frequency range of interest
Market Definition
We explain the “hypothetical monopolist test” that has become the standard methodology for identifying relevant antitrust markets in merger cases, and discuss two approaches to implementing the test. We then focus on the implementation of the test when firms offer multiple products or services, either inside or outside the candidate market, and discuss the “hypothetical cartel test” introduced in the 2010 U.S. Merger Guidelines
Standard environmental testing practices
Manual on procedural requirements for performing certain environmental tests on space flight equipment provides information for test equipment designers, quality control and production engineers. Contents of manual are summarized
Shape computations without compositions
Parametric CAD supports design explorations through generative methods which compose and transform geometric elements. This paper argues that elementary shape computations do not always correspond to valid compositional shape structures. In many design cases generative rules correspond to compositional structures, but for relatively simple shapes and rules it is not always possible to assign a corresponding compositional structure of parts which account for all operations of the computation. This problem is brought into strong relief when design processes generate multiple compositions according to purpose, such as product structure, assembly, manufacture, etc. Is it possible to specify shape computations which generate just these compositions of parts or are there additional emergent shapes and features? In parallel, combining two compositions would require the associated combined computations to yield a valid composition. Simple examples are presented which throw light on the issues in integrating different product descriptions (i.e. compositions) within parametric CAD
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