Analysis of harmonics in indoor Lighting System with LED and fluorescent luminaire
Lighting system is an important part in everyday life. Today, lighting technology has been developing in many aspects. Technology such as Light Emitting Diode (LED) luminaire has been applied to indoor lighting system to replace conventional luminaire. LED lamps have many advantages such as less energy consumption, long life cycle and environmental friendly issue due to without toxic component. However, installation cost is main concern for investor regarding changing conventional lamp toward LED. So, the lighting system in some building are consist of both conventional and LED luminaires. In such a case the power quality must be taken into consideration. This paper aims to study power quality problem in term of harmonics generated by lighting system consisting of both fluorescent and LED luminaires. The obtained result can be used to design filter circuit for harmonic reduction in lighting system.
Abstract The torsional impact response of a penny-shaped crack lying on a bimaterial interface is considered in this study. Laplace and Hankel transforms are used to reduce the problem to the solution of a pair of dual integral equations. The solution to the dual integral equations is expressed in terms of a Fredholm integral equation of the second kind with a finite integral kernel. A numerical Laplace inversion routine is used to recover the time dependence of the solution. The dynamic stress intensity factor is determined and its dependence on time and material constants is discussed.