Reconstructions of total solar irradiance (TSI) rely mainly on linear relations between TSI variation and indices of facular area. When these are extrapolated to the prolonged 15th–17th century Spörer and Maunder solar activity minima, the estimated solar dimming is insufficient to explain the mid-millennial climate cooling of the Little Ice Age. We draw attention here to evidence that the rela...

The star KIC8462852 (Tabby's star) has shown anomalous drops in light flux. We perform a statistical analysis of the more numerous smaller dimming events by using methods found useful for avalanches in ferromagnetism and plastic flow. Scaling exponents for avalanche statistics and temporal profiles of the flux during the dimming events are close to mean field predictions. Scaling collapses sugg...

Photon-axion conversion induced by intergalactic magnetic fields causes an apparent dimming of distant sources, notably of cosmic standard candles such as supernovae of type Ia (SNe Ia). We review the impact of this mechanism on the luminosity-redshift relation of SNe Ia, on the dispersion of quasar spectra, and on the spectrum of the cosmic microwave background. The original idea of explaining...

Extreme ultraviolet spectroscopic observations of one coronal mass ejection event are used to examine the onset phase of the eruption. We find significant dimming of million K plasmas in the low corona under the ascending CME, the activation of an adjacent prominence and 2 million K ‘hot spots’ which may be associated with the CME footpoints. In particular, we show that the dimming is due to a ...

This paper presents a simple alternative of automatic luminous control for electronic ballasts operating in selfsustained oscillating mode feeding fluorescent lamps to energy saving. The luminous flux level control is based on a signal from a lighting dependent resistor, which measures the luminous flux level. The dimming feature is obtained using switching frequency variation. Thus, the circui...

We propose a high dynamic range (HDR) liquid crystal display (LCD) with pixel-level local dimming. The device structure consists of a pixelated LCD dimming panel to control the backlight intensity entering the master LCD panel. According to our analysis and test cell experiment, this dual-panel display system possesses exceedingly high contrast ratio (> 1,000,000:1) and high bit-depth (> 14 bit...

Fluorescent lamps were first introduced to the world in the 1939 World’s Fair. They are low-pressure mercury discharge lamps. Since then, the fluorescent lamps have been the mainly lighting source due to their merits of high color rendering, soft-visualization, long life, and energy-saving. Unfortunately, however, all gas discharge lamps cannot directly connect to a voltage source and require a...

Betelgeuse, one of the most studied red supergiant stars, dimmed in optical by ~1.2 mag between late 2019 and early 2020, reaching an historical minimum called "the Great Dimming." Thanks to enormous observational effort date, two hypotheses remain that can explain Dimming: a decrease effective temperature enhancement extinction caused newly produced circumstellar dust. However, lack multi-wave...