Combined on-line lifetime-energy optimization for asymmetric multicores

In this paper we present an architectural and on-line resource management solution to optimize lifetime reliability of asymmetric multicores while minimizing the system energy consumption, targeting both single nodes (multicores) as well as multiple ones (cluster of multicores). The solution exploits the different characteristics of the computing resources to achieve the desired performance while optimizing the lifetime/energy trade-off. The experimental results show that a combined optimization of energy and lifetime allows for achieving an extended lifetime (similar to the one pursued by lifetime-only optimization solutions) with a marginal energy consumption detriment (less than 2%) with respect to energy-aware but aging-unaware systems

Model-In-the-Loop Testing of Control Systems and Path Planner Algorithms for QuadRotor UAVs

Real systems, as Unmanned Aerial Vehicles (UAVs), are usually subject to disturbances and parametric uncertainties, which could compromise the mission accomplishment, considering particularly harsh environments or challenging applications. For this reason, the main idea proposed in this research is the design of the on-board software, as autopilot software candidate, for a multirotor UAV. In detail, the inner loop of the autopilot system is designed with a variable structure control system, based on sliding mode theory, able to handle external disturbances and uncertainties. This controller is compared with a simple Proportional-Integral-Derivative controller. The key aspects of the proposed methodology are the robustness to bounded disturbances and parametric uncertainties of the proposed combination of guidance and control algorithms. A path-following algorithm is designated for the guidance task, which provides the desired waypoints to the control algorithm. Model-in-the-loop simulations have been performed to validate the proposed approaches. Computationally efficient algorithms are proposed, as combination of a robust control system and path planner. Extensive simulations are performed to show the effectiveness of the proposed methodologies, considering both disturbances and uncertainties

Characterization of a Silicon Drift Detector for High-Resolution Electron Spectroscopy

Silicon Drift Detectors, widely employed in high-resolution and high-rate X-ray applications, are considered here with interest also for electron detection. The accurate measurement of the tritium beta decay is the core of the TRISTAN (TRitium Investigation on STerile to Active Neutrino mixing) project. This work presents the characterization of a single-pixel SDD detector with a mono-energetic electron beam obtained from a Scanning Electron Microscope. The suitability of the SDD to detect electrons, in the energy range spanning from few keV to tens of keV, is demonstrated. Experimental measurements reveal a strong effect of the detector's entrance window structure on the observed energy response. A detailed detector model is therefore necessary to reconstruct the spectrum of an unknown beta-decay source

Global SOLPS-ITER and ERO2.0 coupling in a linear device for the study of plasma-wall interaction in helium plasma

Plasma–wall interaction (PWI) is a great challenge in the development of a nuclear fusion power plant. To investigate phenomena like erosion of plasma-facing components, impurity transport and redeposition, one needs reliable numerical tools for the description of both the plasma and the material evolution. The development of such tools is essential to guide the design and interpretation of experiments in present and future fusion devices. This contribution presents the first global simulation of PWI processes in a linear plasma device mimicking the boundary plasma conditions in toroidal ones, including both the description of plasma and impurity transport and of plasma-facing material evolution. This integrated description is obtained by coupling two of the state-of-the-art numerical codes employed to model the plasma boundary and the PWI, namely SOLPS-ITER and ERO2.0. Investigation of helium plasma is also of primary importance due to the role helium will have during ITER pre-fusion power operation, when it is planned to be used as one of the main plasma species, as well as fusion ash in full power operation. The plasma background is simulated by SOLPS-ITER and the set of atomic reactions for helium plasmas is updated, including charge-exchange and radiative heat losses. ERO2.0 is used to assess the surface erosion in the GyM vessel, using different wall materials (e.g. carbon, iron or tungsten) and applying different biasing voltage. Eroded particles are followed within the plasma to assess their redeposition location. The ionization probability of the different materials in the GyM plasma is inferred through the energy distribution of impacting particles and its effects on migration are investigated

Numerical analysis of interseismic, coseismic and postseismic phases for normal and reverse faulting earthquakes in Italy

The preparation, initiation, and occurrence dynamics of earthquakes in Italy are governed by several frequently unknown physical mechanisms and parameters. Understanding these mechanisms is crucial for developing new techniques and approaches for earthquake monitoring and hazard assessments. Here, we develop a first-order numerical model simulating quasi-static crustal interseismic loading, coseismic brittle episodic dislocations, and postseismic relaxation for extensional and compressional earthquakes in Italy based on a common framework of lithostatic and tectonic forces. Our model includes an upper crust, where the fault is locked, and a deep crust, where the fault experiences steady shear. The results indicate that during the interseismic phase, the contrasting behavior between the upper locked fault segment and lower creeping fault segment generates a stretched volume at depth in the hanging wall via extensional tectonics while a contracted volume forms via compressional tectonics. The interseismic stress and strain gradients invert at the coseismic stage, with the interseismic dilated volume contracting during the coseismic stage, and vice versa. Moreover, interseismic stress gradients promote coseismic gravitational subsidence of the hanging wall for normal fault earthquakes and elastic uplift for reverse fault earthquakes. Finally, the postseismic relaxation is characterized by further ground subsidence and uplift for normal and reverse faulting earthquakes, respectively, which is consistent with the faulting style. The fault is the passive feature, with slipping generating the seismic waves, whereas the energy activating the movement is stored mostly in the hanging wall volume. The main source of energy for normal faulting and thrust is provided by the lithostatic load and elastic load, respectively

Light-induced dipole moment modulation in diarylethenes: a fundamental study

The dipole moment of photochromic diarylethenes is determined in solution for both the coloured and uncoloured forms by measuring the capacitance of a capacitor filled with a photochromic solution as a dielectric material. Diarylethenes with different substituents are investigated and the modulation of the dipole moment is related to their chemical structures. We determine a modulation of the dipole moment up to 4 Debye. We discuss the model used to obtain the dipole moment from the capacitance measurements and we compare the experimental results with the outcomes from DFT calculations. The results highlight the importance of conformational effects in the description of the dipole moment of diarylethenes

An empirical analysis of conviction patterns, change over the life-course and external influences in relation to sexual offending behaviour

This PhD uses statistical analysis and qualitative interviews to analyse behaviour patterns in the context of causal theories of sexual offending and desistance from it, with a particular emphasis on socio-cultural reasons why people offend, stop offending, or offend at different points in life. This research makes an original contribute to the literature in a number of ways. There are six main findings from this research that contribute to the literature in this area. One of the key findings is that there is substantial heterogeneity of offending behaviour amongst sexual offenders, suggesting that there is no one-size-fits-all approach for prevention, intervention or management. There was support in the research for a link between sexual offending and prolific non-sexual offending, but this only appeared to be one of several different sexual offending pathways. Other groups of offenders displayed considerable specialism in their offending (in terms of type of sexual offence and the fact that they had often only been convicted of sexual offences). This was magnified by the finding that offending rates were generally lower for sexual convictions than for other convictions: in fact, the vast majority of people in the dataset only had convictions for one sexual offence. There was evidence from the qualitative interviews that adverse life events were a contributory factor to sexual offending, and the thesis has found that there is support for both psychological and socio-cultural causes (including gender-based elements), as well as an interaction between the two. It also suggested that there is evidence that sexual offending is not stable over the life-course, and that situational factors appear to be important in terms of determining behavioural change. Implications for prevention, intervention and management of sexual offenders are discussed

Standalone vertex finding in the ATLAS muon spectrometer

A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson