The observation of distant supernovae shows that the light of supernovae Ia is dimmer than it would be in a decelerating Universe. Several effects might be responsible for this phenomenon: cosmological constant, evolution of supernovae, selection bias, gravitational lensing, intergalactic dust, and influence of inhomogeneous distribution of matter on light propagation. All these effects but the...

More and more street lighting deployments use LED technology as a light source. Unfortunately, the new also brings some challenges with it that remain unnoticed until installed at scale. This article presents issues related to capacitive reactive power consumed by luminaires. The problem is even profound if luminaire dimmed, because consumes power, which very undesirable in system. Countermeasu...

The design and implementation of an architectural dimming control for multicolor LED-based lighting fixtures is complicated by the need to maintain a consistent color balance under a wide variety of operating conditions. Factors to consider include nonlinear relationships between luminous flux intensity and drive current, junction temperature dependencies, LED manufacturing tolerances and binni...

The aim of this paper is to check if the models with realistic inhomogeneous matter distribution and without cosmological constant can explain the dimming of the supernovae in such a way that it can be interpreted as an acceleration of the Universe. Employing the simplest inhomogeneous model, i.e. Lemâıtre–Tolman model, this paper examines the impact of inhomogeneous matter distribution on ligh...