Search results for "EXPLORATION"
showing 10 items of 201 documents
Co-simulation of bio-inspired multi-agent algorithms
2020
This paper reports on the co-simulation of a team of robots deployed in an exploration task, coordinated by a bio-inspired exploration algorithm. The co-simulation integrates the high-level exploration algorithm with detailed implementations of the robot controllers and kinematic models. Co-simulation results are used to find and correct mismatches between submodels.
Influence of surface processes and initial topography on lateral fold growth and fold linkage mode
2015
Elongation of randomly distributed fold segments and their potential linkage are important for hydrocarbon exploration because it can greatly influence the morphology of the reservoir and both migration and accumulation of hydrocarbons in antiformal traps. Here we study the effects of surface processes and the presence of a topographic slope on the different linkage modes that can occur, and how these parameters affect the required horizontal offset for perturbations to link. The proposed numerical model represents a sedimentary cover detached over a much weaker basal decollement layer. The upper surface is modified by mass redistribution, which is achieved by a combination of fluvial and h…
Ecclesia carinensis. Una sede episcopale alle origini del cristianesimo fra Palermo e Lilibeo; La catacomba paleocristiana di Villagrazia di Carini
2020
The Early Christian cemetery discovered by chance in Villagrazia di Carini in 1899, then forgotten and negletted, has been brought to light from the year 2000 to today thanks to the systematic teamwork of the University of Palermo and the Pontificia Commissione di Archeologia Sacra (PCAS). The unexpected dimension of the site, the largest underground cemetery of Early Christianity so far known in western Sicily, has finally allowed the historiographical debate to find a meeting point on the age-old problem of the existence of ecclesia carinensis, an Early Byzantine diocese attested by the written sources up to the eighth century and disappeared after the centuries of the Islamic domination …
Do soils exist outside Earth?
2010
Abstract On Earth, soils form thanks to the combined action of at least five factors: parent rock, climate, topography, biota, and time. However, the necessity of biota as unavoidable soil forming factor is debated, as important parts of our planet experiencing extreme climates host virtually life-free soils with advanced horizonation. Now that space exploration has greatly expanded our understanding of the Solar System, providing consistent evidences that the loose, unconsolidated "skin" of some nearby rocky bodies is lifeless, it is time to establish if the latter can be considered to be soil in a pedological sense. Our feeling is that, since the concept of soil chiefly bases on the occur…
Typification of the name Senecio pygmaeus (Asteraceae), with some additional taxonomic and phytogeographic remarks
2023
A thorough research on the scientific activity of Guglielmo Gasparrini, Giovanni Gussone and Augustin Pyramus De Candolle allowed the authors to adress a research in several European herbaria looking for the type of the name Senecio pygmaeus DC. The original specimen sent by Gussone and mentioned in the protologue by Candolle is still kept at G-DC and is designated as the lectotype, whilst three other herbarium sheets, preserved at NAP-GUSS, PAL and PAV herbaria respectively, in all probability belong to the same gathering, and are considered as isolectotypes. The authors provide an updated description of this taxon in order to better point out its diagnostic characters. However, further bi…
A numerical study of the Schumann resonances in Mars with the FDTD method
2007
[1] Natural electromagnetic waves generated near the surface by electrostatic discharges in dust storms (dust devils) or by geological activity could be trapped in the resonant cavity formed by the surface and lower ionosphere of Mars, as it occurs on Earth giving rise to Schumann resonances. The finite difference time-domain technique (FDTD) is applied to model the atmosphere of Mars in order to determine Schumann resonant frequencies, and natural electromagnetic fields at the extremely low frequency range (ELF). A numerical tool is provided to analyze the electrical conductivity profile of the Martian atmosphere, with the aim of obtaining Schumann resonance frequencies and their dependenc…
Understanding of tactile pictures in visual impaired children
2015
The present PhD aims at understanding how Visual Impaired (VI) children process the tactile pictures that illustrate the tactile books specially designed for them. Our work is organized around two main axes of analysis. The first axis concentrates on the child who explores the tactile images, while the second axis focuses on the impact that the properties of these images can have on children’s haptic processing. Our researches included children presenting various degrees of visual impairment but without any associated disorders (in particular, without any cognitive delay), distinguishing early blind children from children with low vision. We also compared their performance with those of sig…
Design and control of a novel 3D casting manipulator
2010
This paper focuses on casting manipulation and presents an innovative mechanism that allows objects placed in a three-dimensional space to be reached with a relatively small robot. Casting manipulation is a technique by which a robotic end-effector is thrown and its ballistic flight is controlled through a tether cable so as to reach a target object. Previous work presented a solution that is viable only when the position of the target object is perfectly known or aligned with the throwing plane. Our work extends the technique by use of a novel mechanical design of the arm, and a suitable control scheme for the flight of the end-effector, which makes it applicable for objects placed at gene…
A Rough-Terrain Casting Robot for the ESA Lunar Robotics Challenge
2009
This paper describes the design and implementation of DAVID, a lunar vehicle developed for the European Space Agency (ESA) Lunar Robotics Challenge, presenting severe terrain negotiation and sample acquisition challenges. We discuss in some detail two of the main innovative aspects of our entry to the challenge, i.e. the locomotion system and the sample acquisition system. Motivated by the challenge specifications, a range of different locomotion systems were considered, among which we chose a simple, rugged and effective wheeled system. We provide an account of the choice of five different types of wheels, which were designed, analyzed and experimentally tested in conditions similar to the…
La alimentación en los viajes espaciales tripulados: desde el Programa Gemini hasta la ISS/Shuttle
2014
Los alimentos espaciales han tenido una gran importancia en el desarrollo de las misiones espaciales tripuladas ya que constituyen la única fuente de energía y nutrientes para el ser humano fuera del planeta Tierra. Dichos alimentos han experimentado una gran evolución desde el inicio del Programa Mercury hasta las actuales misiones a la International Space Station (ISS). En un primer momento eran diseñados para ofrecer una gran densidad energética y nutritiva y actualmente se da prioridad a las características organolépticas y psicológicas, ya que contribuyen a un mayor consumo y un mejor estado nutricional de los astronautas. El objetivo del presente estudio es hacer un análisis retrospec…