There are several types of dimmers generally available. Those employing triac or thyristor devices operate in a very similar fashion. These are used for resistive, and inductive loads, such as incandescent, cold cathode and low voltage (inductive) lamp sources. Note that not all electronic transformers used for low voltage lamps are suitable for dimming by triac or thyristor dimmers. Specialist...

Why do some people bounce back from life's hardships while others despair? HBR senior editor Diane Coutu looks at the nature of individual and organizational resilience, issues that have gained special urgency in light of the recent terrorist attacks, war, and recession. In the business arena, resilience has found its way onto the list of qualities sought in employees. As one of Coutu's intervi...

Before Neuroimaging came along most information from the brain was gathered by destructive techniques, like vivisection. The problem with this was that you either had to rely on animals or use dead humans. So it was nearly impossible to study topics like brain development or how external influences take effect on the brain. Neuroimaging changed that and now allows us to conduct experiments on h...

Here is a proof for the demeaning method used in lfe, and a description of the methods used for solving the residual equations. As well as a toy-example. This is a preliminary version of [3]. This method, formulated as the Gauss-Seidel algorithm, was noted in [4] without the author noticing it in the first version of this paper.

The popular mythology surrounding the U.S. venture-capital industry derives from a previous era. Venture capitalists who nurtured the computer industry in its infancy were legendary both for their risk taking and for their hands-on operating experience. But today things are different, and separating the myths from the realities is crucial to understanding this important piece of the U.S. econom...