A detector-based spectral irradiance scale has been realized at the National Institute of Standards and Technology (NIST). Unlike the previous NIST spectral irradiance scales, the new scale is generated with filter radiometers calibrated for absolute spectral power responsivity traceable to the NIST high-accuracy cryogenic radiometer instead of with the gold freezing-point blackbody. The calibr...

A stochastic radiative transfer equation for the mean l( → X), cosine of polar angle of direction → X d( → X2 → X0), Dirac delta function field and its solution for the case of discontinuous vegetation canopies is discussed in this article. The equation set v(→r ), indicator function Fdir(k), extraterrestrial solar radiance at the top of satisfies the law of energy conservation and is amenable ...

In considering the possibility of the existence of Extraterrestrial Intelligence, an independent means of verifying eyewitness accounts of flying saucers and alien beings on Earth is proposed. The approach would be an archaeological one whereby various archaeological surveying and excavation techniques would be used to examine an alleged landing or crash site of an extraterrestrial craft. The a...

I first argue that the extraterrestrials we will find will not communicate, for the simple reason that they would likely be either immensely inferior or immensely superior to us. Then, I argue that the discovery of extraterrestrials will be slow, like other previous major scientific discoveries. I introduce a multidimensional model to assess and to prepare the impact of discovering extraterrest...

1 Corresponding author. Abstract – Accurate measurement and characterisation of fluctuations in the irradiance environment is important in many areas of optical remote sensing. This paper reports a method of estimating spectral irradiance over the VNIR region (400 1100nm) from the radiance of a calibrated reference panel, measured in seven narrow (10nm) spectral bands. The irradiance spectrum w...

Classical radiative transfer programs are based on the plane-parallel assumption. We show that the Gershun equation is valid if the irradiance is averaged over a sufficiently large area. We show that the equation is invalid for horizontal areas of the order of tens of meters in which horizontal gradients of irradiance in the presence of waves are much larger than vertical gradients. We calculat...

Rapid variations in the intensities of light are commonly observed in profiles of downwelling plane irradiance in the ocean. These fluctuations are often treated as noise and filtered out. Here an effort is made to extract the pertinent statistics to quantify the light field fluctuations from vertical profiles of irradiance measured under clear skies. The irradiance data are collected in oceani...

1. The effect of light fluctuations on the growth rates of four species of freshwater phytoplankton was investigated. Experimental light regimes included constant irradiance and fluctuations of a step function form, with equal proportion of high (maximum of 240 mmol photons m s) and low light (minimum of 5 mmol photons m s) (or dark) in a period. Fluctuations of 1, 8 and 24-h periods were impos...

Anoectochilus roxburghii was grown under different shade treatments-50%, 30%, 20%, and 5% of natural irradiance-to evaluate its photosynthetic characteristics, chloroplast ultrastructure, and physiology. The highest net photosynthetic rates and stomatal conductance were observed under 30% irradiance, followed in descending order by 20%, 5%, and 50% treatments. As irradiance decreased from 50% t...

Irradiance Caching is one of the most widely used algorithms to speed up global illumination. In this paper, we propose an algorithm based on the Irradiance Caching scheme that allows us (1) to adjust the density of cached records according to illumination changes and (2) to efficiently render the high-frequency illumination changes. To achieve this, a new record footprint is presented. Althoug...