Una visión de la obra y el herbario de Rouy a través del género Carex L.

Se analiza la obra de Georges Rouy, célebre botánico francés, mediante el estudio de sus materiales así como del tratamiento del género Carex (Cyperaceae) en la Flore de France. Se valora favorablemente el conocimiento que el autor demuestra sobre este género, puesto de manifi esto al incluir subgéneros en la clasifi cación taxonómica. Asimismo la sinonimia que propone para cada nombre y las descripciones de los taxones son muy completas. Al contrario, se valora negativamente la excesiva fragmentación que estableció, pues incluyó demasiadas secciones y subsecciones. Finalmente, su rechazo a utilizar las normas nomenclaturales establecidas por el Código de Nomenclatura Botánica conduce a la confusión e impide que la mayoría de sus nombres sean válidos.The George Rouy’s work, a famous French botanist, is studied by means of his material and literature of the genus Carex (Cyperaceae). We assess positively the knowledge that he demonstrated of this genus; because of the subgenera differentiated in his treatment, besides the complete synonymy presented for each name and the taxa descriptions. But he splitted excessively the infrageneric classifi cation including too many sections and subsections. Finally, most of the names he proposed are invalid because of his rejection of the International Code of Botanical Nomenclature recommendations and rules

Spatio-temporal estimation of wind speed and wind power using extreme learning machines: predictions, uncertainty and technical potential

With wind power providing an increasing amount of electricity worldwide, the quantification of its spatio-temporal variations and the related uncertainty is crucial for energy planners and policy-makers. Here, we propose a methodological framework which (1) uses machine learning to reconstruct a spatio-temporal field of wind speed on a regular grid from spatially irregularly distributed measurements and (2) transforms the wind speed to wind power estimates. Estimates of both model and prediction uncertainties, and of their propagation after transforming wind speed to power, are provided without any assumptions on data distributions. The methodology is applied to study hourly wind power potential on a grid of 250×250 m2 for turbines of 100 m hub height in Switzerland, generating the first dataset of its type for the country. We show that the average annual power generation per turbine is 4.4 GWh. Results suggest that around 12,000 wind turbines could be installed on all 19,617 km2 of available area in Switzerland resulting in a maximum technical wind potential of 53 TWh. To achieve the Swiss expansion goals of wind power for 2050, around 1000 turbines would be sufficient, corresponding to only 8% of the maximum estimated potential

Quantum Hall effect in exfoliated graphene affected by charged impurities: metrological measurements

Metrological investigations of the quantum Hall effect (QHE) completed by transport measurements at low magnetic field are carried out in a-few-$\mu\mathrm{m}$-wide Hall bars made of monolayer (ML) or bilayer (BL) exfoliated graphene transferred on $\textrm{Si/SiO}_{2}$ substrate. From the charge carrier density dependence of the conductivity and from the measurement of the quantum corrections at low magnetic field, we deduce that transport properties in these devices are mainly governed by the Coulomb interaction of carriers with a large concentration of charged impurities. In the QHE regime, at high magnetic field and low temperature ($T<1.3 \textrm{K}$), the Hall resistance is measured by comparison with a GaAs based quantum resistance standard using a cryogenic current comparator. In the low dissipation limit, it is found quantized within 5 parts in $10^{7}$ (one standard deviation, $1 \sigma$) at the expected rational fractions of the von Klitzing constant, respectively $R_{\mathrm{K}}/2$ and $R_{\mathrm{K}}/4$ in the ML and BL devices. These results constitute the most accurate QHE quantization tests to date in monolayer and bilayer exfoliated graphene. It turns out that a main limitation to the quantization accuracy, which is found well above the $10^{-9}$ accuracy usually achieved in GaAs, is the low value of the QHE breakdown current being no more than $1 \mu\mathrm{A}$. The current dependence of the longitudinal conductivity investigated in the BL Hall bar shows that dissipation occurs through quasi-elastic inter-Landau level scattering, assisted by large local electric fields. We propose that charged impurities are responsible for an enhancement of such inter-Landau level transition rate and cause small breakdown currents.Comment: 14 pages, 9 figure

The DoF-Box project: An educational kit for configurable robots

China: Shanghai. AirportCNAC is the China National Aviation Corporation. The Shanghai Longhua Airport.GrayscaleForman Nitrate Negatives, Box 2

The Development of Khepera

This short paper explains how the Khepera robot was developed, from the initial idea to the its commercialisation by K-Team. The goal of this paper is not a scientific analysis but an historical overview of the steps made in the development of this robot since 1991. The papers introduces first the situation of the team who started the development, then decisions made in creating the actual Khepera are briefly described, as well as some important steps in the commercialisation of the robot. We conclude with the current status of Khepera, and introduce other products that have evolved from Khepera

Design of a Biomimetic Upper Body for the Humanoid Robot Robota

This paper presents the current prototype of doll-shaped humanoid robot Robota. The use of the robot Robota as part of studies with disabled children sets a number of constraints on its design. In particular, it requires that the robot bears a human likeness both in its body features and in the kinematics of its motions. In this paper, we present the design of a 23 degrees of freedom upper body for Robota, including a 3 DOFs spine, two 7 DOFs arm, a 3 DOFs pair of eyes and a 3 DOFs neck

Development of a Miniature Pair of Eyes With Camera for the Humanoid Robot Robota

A growing trend in humanoid robotics tend at reducing the size of humanoids in order to lower their building costs. While growing small has its advantages, it also has drawbacks. In particular, providing miniature humanoids with the same sensorimotor capabilities as their grown-up peers is a challenge, both in terms of mechanics, electronics and control. The Robota project creates humanoids, whose size should match that of a commercial doll, so that they can be used as part of experiments with autistic children. Because these experiments measure the child's ability to socially interact with others, it is fundamental to provide the robot with sensory capabilities, such as speech and vision, that are at the basis of these interactions. This paper presents the creation of a miniature pair of mobile eyes, mounted with miniature cameras to provide Robota with binocular and mobile vision. The system allows the robot to blink, to direct its gaze toward or away from its user and to track the user's face