Theoretical aspects of dimming an incandescent lamp

Abstract

A dimmer is an electronic device that controls alternate voltage applied to a lamp through delivering a selected portion of the mains sinusoid. Engineer, designing a dimmer needs to estimate how big this portion should be to get a desired luminance level. This article uses a model of incandescent lamp, tungsten resistivity, and human eye spectral efficiency to derive dependency of produced luminous flux over the voltage, gives a simple analytical function that describes this dependency with good accuracy (±2% comparing to the model).

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Customizing ErWin templates for PostgreSQL

ErWin 7.2 does not provide support for PostgreSQL, indeed with few tricks it still can be used to model database and generate valid SQL code.

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