Rat Spatial Discounting and Value Appraisal

In psychology, the Traveling Salesman Problem (TSP) is used as a spatial task that requires the selection of an efficient route among multiple targets. One strategy rats may use to solve the TSP is the nearest neighbor strategy. This technique is founded on two key assumptions: first, that rats possess the perceptual acuity to compare relative target distances, and secondly, that they are motivated to select routes that optimize efficiency. This study aims to investigate rats\u27 ability to compare relative distances of targets. Each rat underwent eight trials, five in an open maze and three in a T-maze. Each rat began in a start box, and was given a choice between two targets, each containing one or more cocoa pebbles. The two choices differed in distance, number of treats, or both. Trials were recorded via video camera. Statistical analyses were completed to explore the relationships between latency, quantity of cocoa pebbles, distance to the target, and sex. The trial latency in both open and T-maze’s decreased significantly over time. The difference in choice distance significantly influenced the probability of choosing each side, but preliminary analysis of the difference in quantity suggests no effect of quantity

Anisotropic heat conduction in silicon nanowire network revealed by Raman scattering

Anisotropic nanomaterials possess interesting thermal transport properties because they allow orientation of heat fluxes along preferential directions due to a high ratio (up to three orders of magnitude) between their in-plane and cross-plane thermal conductivities. Among different techniques allowing thermal conductivity evaluation, micro-Raman scattering is known to be one of the most efficient contactless measurement approaches. In this letter, a new experimental approach based on Raman scattering measurements with variable laser spot sizes is reported. Correlation between experimental and calculated thermal resistances of one-dimensional nanocrystalline solids allows simultaneous estimation of their in-plane and cross-plane thermal conductivities. In particular, our measurement approach is illustrated to be successfully applied for anisotropic thermal conductivity evaluation of silicon nanowire arrays

Thermally induced evolution of the structure and optical properties of silicon nanowires

In the present paper, we report on the investigation of thermal annealing (TA) effect on structural and optical properties of crystalline silicon nanowires produced by metal-assisted chemical etching approach. In particular, the impact of TA on nanowire length, relative volume and size distribution of voids is described in terms of Lifshitz-Slyozov-Wagner theory considering the TA induced Oswald ripening in the SiNW arrays. It was also found that TA leads to a decrease of the SiNWs total reflection in the wide UV–VIS-IR spectral range. The reported effects can be used for tuning of crystalline SiNWs arrays in view of their further applications in photonics related fields. © 2020 The Author

Light dynamics in glass-vanadium dioxide nanocomposite waveguides with thermal nonlinearity

We address the propagation of laser beams in Si02-VO2 nanocomposite waveguides with thermo-optical nonlinearity. We show that the large modifications of the absorption coefficient as well as notable changes of refractive index of VO2 nanoparticles embedded into the SiO2 host media that accompany the semiconductor-to-metal phase transition may lead to optical limiting in the near-infrared wave range.Comment: 13 pages, 3 figures, to appear in Optics Letter

A mobile vibro-robot for locomotion through pipelines

The subject of our work is the creation of different designs of mobile robots for the movement through pipelines and similar technical systems. Using the transversal vibrations of an elastic bristle body, allows us to develop a new crawling vibro-robot. The motion is mainly realized by anisotropic friction forces. For the design process, we use the well-known construction principle of combination of alternative systems. It enables the transfer of structural characteristics (i.e. its kinematics) from one object to another, leading to new desirable characteristics or optimisations of existing technical objects. An analytical model of the motion of the bristles is presented