Instituto Superior Técnico

About: Instituto Superior Técnico is a based out in . It is known for research contribution in the topics: Catalysis & Finite element method. The organization has 10085 authors who have published 30226 publications receiving 667524 citations. The organization is also known as: IST & Instituto Superior Tecnico.

Pervasive Aeolian Activity Along Rover Curiosity's Traverse in Gale Crater, Mars

Abstract: The NASA Mars Science Laboratory (MSL) rover, Curiosity, has safely landed near a 35-km-long dark dune field in Gale Crater on Mars. This dune field crosses the landing site from the northeast to the southwest and lies along Curiosity’s traverse to Aeolis Mons. Here we present the first evidence of recent aeolian activity in the form of ripple and dune migration, and further estimate wind directions within the dune field through analysis of ripple and dune morphologies and the Mars Regional Atmospheric Modeling System (MRAMS). We measured a minimum ripple migration rate of 0.66 m per Earth year, and dune migration rate of 0.4 m per Earth year, in the southwest portion of the field. A strongly bidirectional ripple crestline orientation, nearly orthogonal dune slipfaces, and linear seif or oblique dunes indicate a bidirectional wind regime with winds mainly coming from the ENE and from the northwest; however, MRAMS results indicate primary winds from the ENE. Our constraints on the wind regime provide the unique opportunity to use ground measurements from MSL to test the accuracy of winds predicted from orbital data.

Efficient and Mild Carbon Dioxide Hydrogenation to Formate Catalyzed by Fe(II) Hydrido Carbonyl Complexes Bearing 2,6-(Diaminopyridyl)diphosphine Pincer Ligands

Abstract: Fe(II) hydrido carbonyl complexes supported by PNP pincer ligands based on the 2,6-diaminopyridine scaffold were found to promote the catalytic hydrogenation of CO2 and NaHCO3 to formate in protic solvents in the presence of bases, reaching quantitative yields and high TONs under mild reaction conditions, with pressures as low as 8.5 bar and temperatures as low as 25 °C. NMR and DFT studies highlighted the role of dihydrido and hydrido formate complexes in catalysis.

Quantum physics exploring gravity in the outer solar system: the SAGAS project

Abstract: We summarise the scientific and technological aspects of the Search for Anomalous Gravitation using Atomic Sensors (SAGAS) project, submitted to ESA in June 2007 in response to the Cosmic Vision 2015–2025 call for proposals. The proposed mission aims at flying highly sensitive atomic sensors (optical clock, cold atom accelerometer, optical link) on a Solar System escape trajectory in the 2020 to 2030 time-frame. SAGAS has numerous science objectives in fundamental physics and Solar System science, for example numerous tests of general relativity and the exploration of the Kuiper belt. The combination of highly sensitive atomic sensors and of the laser link well adapted for large distances will allow measurements with unprecedented accuracy and on scales never reached before. We present the proposed mission in some detail, with particular emphasis on the science goals and associated measurements and technologies.

Complete coverage path planning and guidance for cleaning robots

Abstract: This paper describes a complete coverage path planning and guidance methodology for a mobile robot, having the automatic floor cleaning of large industrial areas as a target application. The proposed algorithms rely on the a priori knowledge of a 2D map of the environment and cope with unexpected obstacles not represented on the map. A template based approach is used to control the path execution, thus incorporating, in a natural way, the kinematic and the geometric model of the mobile robot on the path planning procedure. The novelty of the proposed approach is the capability of the path planner to deal with a priori mapped or unexpected obstacles in the middle of the working space. If unmapped obstacles permanently block the planned trajectory, the path tracking control avoids these obstacles. The paper presents experimental results with a LABMATE mobile robot, confirming the feasibility of the total coverage path and the robustness of the path tracking behaviour based control.