How many different classes of partially distinguishable landmarks are needed to ensure that a robot can always see a landmark without simultaneously seeing two of the same class? To study this, we introduce the chromatic art gallery problem. A guard set S ⊂ P is a set of points in a polygon P such that for all p ∈ P , there exists an s ∈ S such that s and p are mutually visible. Suppose that tw...

The Courtauld Gallery occupies a unique position in central London as a university art museum and key facilitator for collaborative opportunities between research academics and curatorial practitioners. Given the context of the gallery as an institution housed within a building not purpose-built for the function of exhibition, the ways in which the gallery space acts as a directive on visitors’...

It is shown that in any polygonal art gallery of n sides it is possible to place bn/3c point guards whose range of vision is 180◦ so that every interior point of the gallery can be seen by at least one of them. The guards can be stationed at any point of the art gallery. This settles an open problem posed by J. Urrutia.  2000 Elsevier Science B.V. All rights reserved.

The external fields of optical whispering gallery modes may be used to confine atoms in stable orbits around a dielectric microsphere. As an example, a toroidal dipole-force trap (atom gallery) for three-level atoms is investigated, and the possibility of achieving an atomic (matter-wave) resonator is discussed. The extremely small electromagnetic mode volumes and high Q's of the whispering gal...

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abstract infiltration process is one of the most important components of the hydrological cycle. on the other hand, the direct measurement of infiltration process is laborious, time consuming and expensive. in this study, the possibility of predicting cumulative infiltration in specific time intervals, using readily available soil data and artificial neural networks (anns) was investigated. for...

abstract infiltration is one of the most important phenomena which is affected by the soil physical and hydraulic characteristics. measurement of infiltration needs the high cost and is time consuming, therefore estimation of infiltration is necessary. also, due to variability of soil moisture, it is important to determine the appropriate model for the estimating the infiltration rate. the pres...