ShakeAlert: An earthquake warning from your cellphone
ShakeAlert is a prototype earthquake early warning system for the West Coast. ShakeAlert for cellphones would warn users when ground shaking from a nearby earthquake will reach them, allowing time to duck and cover, as in this video dramatization.
ShakeAlert is currently being tested by some utilities, transportation systems and cities to shut down critical systems that could be damaged or cause injury during violent shaking.
Physics 111 Advanced Laboratory
This video accompanies the Non-Linear Dynamics and Chaos Experiment, providing students with an introduction to the theory, apparatus, and procedures.
This experiment is an introduction to Non-Linear Dynamics, Data Acquisition, Chaos theory and Fractals. Limited as we are by our senses and relatively short powers of recall, much of the physical world seems aperiodic and defies quantitative description. While we have yet to discover closed form solutions to the simplest of systems (e.g. the one-dimensional gravitational three-body problem), the field of chaos reveals structure in their dynamics. The results of chaos theory have found practical applications in almost every branch of science.
In this experiment you will study the response of at least two different dynamical systems: A non-linear, damped harmonic oscillator and a system of op amps that reproduces the Lorentz attractor. You will measure their linear and non-linear behavior using software to measure their information dimension.
You will learn the basics of digital sampling, Fourier transforms, geometric analysis of autonomous differential equations, information entropy, correlation dimension and the basics of programming in LabView (a data-acquisition and control language written by National Instruments).
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