François Alphonse Forel (1890) and Willi Ule (1892) composed a colour comparator scale, with tints varying from indigo-blue to cola brown, to quantify the colour of natural waters, like seas, lakes and rivers. For each measurement, the observer compares the colour of the water above a submersed white disc (Secchi disc) with a hand-held scale of pre-defined colours. The scale can be well reprodu...

In this paper, we discuss semidefinite relaxation techniques for computing minimal size ellipsoids that bound the solution set of a system of uncertain linear equations (ULE). The proposed technique is based on the combination of a quadratic embedding of the uncertainty, and the Sprocedure. The resulting bounding condition is expressed as a Linear Matrix Inequality (LMI) constraint on the ellip...

Remote sensing technology is a timely and cost-efficient method for leaf area index (LAI) estimation, especially less accessible areas such as mangrove forests. Confounded by the poor penetrability of optical images, most previous studies focused on estimating LAI main canopy, ignoring understory. This study investigated capability multispectral Sentinel-2 (S2) imagery, airborne hyperspectral i...

The paper demonstrates that product configuration applications fit naturally the framework of answer set programming. It is shown that product configuration knowledge can be represented systematically and compactly using a logic program type rule language such that the answers of a configuration task, the configurations, correspond to the models of the rule representation.. The paper pr.es.~nts...

We demonstrate a powerful tool for high-resolution mid-IR spectroscopy and frequency metrology with quantum cascade lasers (QCLs). We have implemented frequency stabilization of a QCL to an ultra-low expansion (ULE) reference cavity, via upconversion to the near-IR spectral range, at a level of 1×10(-13). The absolute frequency of the QCL is measured relative to a hydrogen maser, with instabili...

This paper explores parallels between on epts de ned in ryptography and on epts of biology at di erent levels of organization. Cryptographi settings, in luding the presen e of an eavesdropper are extensive in the realm of plants and animals. It also turns out that priniples of information prote tion show strong similarities between the two dis iplines: omputer s ien e and mole ular biology. Bio...

We describe the design, construction, and characterization of a medium-finesse Fabry–Pérot cavity for simultaneous frequency stabilization of two lasers operating at 960 and 780 nm wavelengths, respectively. The lasers are applied in experiments with ultracold rubidium Rydberg atoms, for which a combined laser linewidth similar to the natural Rydberg linewidth (≈ 10 kHz) is desired. The cavity,...