Tune shift with amplitude of the system. When the tune reaches resonant values, it can be unstable, and thus a tune-shift with amplitude can limit the stability region, or dynamic aperture. In classical mechanics, a simple example of a system with tune shift with amplitude is a pendulum. In accelerator physics, both the transverse and the longitudinal dynamics show tune shift with amplitude. A simple model of the transverse dynamics is of an oscillator with a single sextupole, it is referred to as the Hénon map. Another model for this case is the Standard Map. An important example is the typical case of distributed
Cassandra (metaphor) applied in a variety of contexts such as psychology, environmentalism, politics, science, cinema, the corporate world, and in philosophy, and has been in circulation since at least 1949 when French philosopher Gaston Bachelard coined the term 'Cassandra Complex' to refer to a belief that things could be known in advance. The Cassandra metaphor is applied by some psychologists to individuals who experience physical and emotional suffering as a result of distressing personal perceptions, and who are disbelieved when they attempt to share the cause of their suffering with others. In 1963, psychologist Melanie Klein provided an interpretation of Cassandra as