Improved approximation of spatial light distribution

Improved approximation of spatial light distribution

The rapid worldwide evolution of LEDs as light sources has brought new challenges, which means that new methods are needed and new algorithms have to be developed. Since the majority of LED luminaries are of the multi-source type, established methods for the design of light engines cannot be used in the design of LED light engines. This is because in the latter case what is involved is not just...

Improved Dynami Spatial Approximation Trees

Improved Deletions in Dynamic Spatial Approximation Trees

The Dynamic Spatial Approximation Tree (dsa–tree) is a recently proposed data structure for searching in metric spaces. It has been shown that it compares favorably against alternative data structures in spaces of high dimension or queries with low selectivity. The dsa–tree supports insertion and deletions of elements. However, it has been noted that deletions degrade the structure over time, s...

Effects of light and sound stimuli on spatial distribution and swimming activity of Daphnia under laboratory conditions

Aquatic ecosystems are heterogeneous in terms of light and sound distribution. The aim of this study was to investigate the effect of environmental abiotic factors, light and sound stimuli, on Daphnia (Daphnia magna) swimming behaviour.  Here, we examined behavioural changes of Daphnia (N=24) in response to light and sound treatments simultaneously. The treatments concerned a 2×2 design with br...

Heuristics for Optimization of LED Spatial Light Distribution Model

Recent development of LED technology enabled production of lighting systems with nearly arbitrary light distributions. A nontrivial engineering task is to design a lighting system or a combination of luminaries for a given target light distribution. Here we use heuristics for solving a problem related to this engineering problem, restricted to symmetrical distributions. A genetic algorithm and ...