1,711 research outputs found
Signal Reconstruction via H-infinity Sampled-Data Control Theory: Beyond the Shannon Paradigm
This paper presents a new method for signal reconstruction by leveraging
sampled-data control theory. We formulate the signal reconstruction problem in
terms of an analog performance optimization problem using a stable
discrete-time filter. The proposed H-infinity performance criterion naturally
takes intersample behavior into account, reflecting the energy distributions of
the signal. We present methods for computing optimal solutions which are
guaranteed to be stable and causal. Detailed comparisons to alternative methods
are provided. We discuss some applications in sound and image reconstruction
Numerical Evaluation of long-term Stability
The problem of predicting long-term particle loss in 4D betatronic motion is considered. A phenomenological scenario is derived through numerical tools based on tracking and frequency analysis. A three-parameter formula to interpolate the dynamic aperture versus the number of turns is proposed. The agreement with tracking data is excellent, and the extrapolation for very high number of turns agrees with the onset of chaos evaluated through the Lyapunov method
Better Benefits: Reforming Teacher Pensions for a Changing Work Force
Explains how defined-benefit pension plans create barriers to attracting, retaining, and distributing effective teachers equitably. Proposes reforms including changing the benefit formula or structure, limiting political pressure, and phasing in changes
Hubble Space Telescope: Optical telescope assembly handbook. Version 1.0
The Hubble Space Telescope is described along with how its design affects the images produced at the Science Instruments. An overview is presented of the hardware. Details are presented of the focal plane, throughput of the telescope, and the point spread function (image of an unresolved point source). Some detailed simulations are available of this, which might be useful to observers in planning their observations and in reducing their data
Publications of the Jet Propulsion Laboratory, July 1964 through June 1965
JPL publications bibliography with abstracts - reports on DSIF, Mariner program, Ranger project, Surveyor project, and other space programs, and space science
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