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At the beginning of the 20th century, Kristian Birkeland (1867-1917), a Norwegian scientist of insatiable curiosity, addressed questions that had vexed European scientists for centuries. Why do the northern lights appear overhead when the earth s magnetic field is disturbed? How are magnetic storms connected to disturbances on the sun? To answer these questions Birkeland interpreted his advance laboratory simulations and daring campaigns in the Arctic wilderness in the light of Maxwell s newly discovered laws of electricity and magnetism. Birkeland s ideas were dismissed for decades, only...

This biography summarizes the seminal contributions to auroral and space science of Carl Stormer (1874 - 1957). He was the first to develop precise photographic methods to calculate heights and morphologies of diverse auroral forms during four solar cycles. Stormer independently devised numerical techniques to determine the trajectories of high-energy charged particles allowed and forbidden in the Earth's magnetic field. His theoretical analyses explained cosmic ray access to the upper atmosphere, 20 years before they were identified by other scientists. Stormer's crowning achievement,...

At the beginning of the 20th century, Kristian Birkeland (1867-1917), a Norwegian scientist of insatiable curiosity, addressed questions that had vexed European scientists for centuries. Why do the northern lights appear overhead when the earth s magnetic field is disturbed? How are magnetic storms connected to disturbances on the sun? To answer these questions Birkeland interpreted his advance laboratory simulations and daring campaigns in the Arctic wilderness in the light of Maxwell s newly discovered laws of electricity and magnetism. Birkeland s ideas were dismissed for decades, only...

The auroral emissions in the upper atmosphere of the polar regions of the Earth are evidence of the capture of energetic particles from the Sun, streaming by the Earth as the solar wind. These auroral emissions, then, are a window to outer space, and can provide us with valuable information about electrodynamic coupling processes between the solar wind and the Earth's ionosphere and upper atmosphere. Studying the physics of these phenomena extends our understanding of our plasma universe.

Ground-based remote-sensing techniques, able to monitor continuously the variations in the...

Many important physical systems have input-output properties related to the conservation, dissipation and transport of energy. The theory surrounding such "dissipative properties" may be used as a framework for the design and analysis of control systems. The consideration of dissipativity is useful and may be indispensable for control applications like robotics, active vibration damping and circuit theory and for some control techniques themselves: adaptive, nonlinear-H-infinity, and inverse-optimal control among them.

Dissipative Systems Analysis and Control...