Zero-Dimensionality and Serre Rings

2000 Mathematics Subject Classification: Primary 13A99; Secondary 13A15, 13B02, 13E05.

Equimultiple Locus of Embedded Algebroid Surfaces and Blowing–up in Characteristic Zero

2000 Mathematics Subject Classification: 14B05, 32S25.

Hausdorff Approximation of Functions Different from Zero at One Point - Implementation in Programming Environment Mathematica

ACM Computing Classification System (1998): G.1.2.

Simultaneous multichannel carrier-suppressed return-to-zero to non-return-to-zero format conversion using a fiber Bragg grating

A novel multichannel carrier-suppressed return-to-zero (CSRZ) to non-return-to-zero (NRZ) format conversion scheme based on a single custom-designed fiber Bragg grating (FBG) with comb spectra is proposed. The spectral response of each channel is designed according to the algebraic difference between the CSRZ and NRZ spectra outlines. The tailored group delays are introduced to minimize the maximum refractive index modulation. Numerical results show that four-channel 200-GHz-spaced CSRZ signals at 40 Gbits/s can be converted into NRZ signals with high Q-factor and wide-range robustness. It is shown that our proposed FBG is robust to deviations of bandwidth and central wavelength detuning. Another important merit of this scheme is that the pattern effects are efficiently reduced owing to the well-designed spectra response.

Achieving zero accidents—A strategic framework for continuous safety improvement in the construction industry

In the U.S., construction accidents remain a significant economic and social problem. Despite recent improvement, the Construction industry, generally, has lagged behind other industries in implementing safety as a total management process for achieving zero accidents and developing a high-performance safety culture. One aspect of this total approach to safety that has frustrated the construction industry the most has been “measurement”, which involves identifying and quantifying the factors that critically influence safe work behaviors. The basic problem attributed is the difficulty in assessing what to measure and how to measure it—particularly the intangible aspects of safety. Without measurement, the notion of continuous improvement is hard to follow. This research was undertaken to develop a strategic framework for the measurement and continuous improvement of total safety in order to achieve and sustain the goal of zero accidents, while improving the quality, productivity and the competitiveness of the construction industry as it moves forward. The research based itself on an integral model of total safety that allowed decomposition of safety into interior and exterior characteristics using a multiattribute analysis technique. Statistical relationships between total safety dimensions and safety performance (measured by safe work behavior) were revealed through a series of latent variables (factors) that describe the total safety environment of a construction organization. A structural equation model (SEM) was estimated for the latent variables to quantify relationships among them and between these total safety determinants and safety performance of a construction organization. The developed SEM constituted a strategic framework for identifying, measuring, and continuously improving safety as a total concern for achieving and sustaining the goal of zero accidents.

Exergoeconomic analysis of solar organic rankine cycle for geothermal air conditioned net zero energy buildings

This study is an attempt at achieving Net Zero Energy Building (NZEB) using a solar Organic Rankine Cycle (ORC) based on exergetic and economic measures. The working fluid, working conditions of the cycle, cycle configuration, and solar collector type are considered the optimization parameters for the solar ORC system. In the first section, a procedure is developed to compare ORC working fluids based on their molecular components, temperature-entropy diagram and fluid effects on the thermal efficiency, net power generated, vapor expansion ratio, and exergy efficiency of the Rankine cycle. Fluids with the best cycle performance are recognized in two different temperature levels within two different categories of fluids: refrigerants and non-refrigerants. Important factors that could lead to irreversibility reduction of the solar ORC are also investigated in this study. In the next section, the system requirements needed to maintain the electricity demand of a geothermal air-conditioned commercial building located in Pensacola of Florida is considered as the criteria to select the optimal components and optimal working condition of the system. The solar collector loop, building, and geothermal air conditioning system are modeled using TRNSYS. Available electricity bills of the building and the 3-week monitoring data on the performance of the geothermal system are employed to calibrate the simulation. The simulation is repeated for Miami and Houston in order to evaluate the effect of the different solar radiations on the system requirements. The final section discusses the exergoeconomic analysis of the ORC system with the optimum performance. Exergoeconomics rests on the philosophy that exergy is the only rational basis for assigning monetary costs to a system’s interactions with its surroundings and to the sources of thermodynamic inefficiencies within it. Exergoeconomic analysis of the optimal ORC system shows that the ratio Rex of the annual exergy loss to the capital cost can be considered a key parameter in optimizing a solar ORC system from the thermodynamic and economic point of view. It also shows that there is a systematic correlation between the exergy loss and capital cost for the investigated solar ORC system.

Rilievo fotogrammetrico da drone per la generazione di modelli termici di porzioni di territorio

In questo elaborato viene sperimentato un iter processuale che consenta di utilizzare i sensori termici affiancati a fotocamere digitale in ambito fotogrammetrico al fine di ottenere prodotto dal quale sono estrapolabili informazioni geometriche e termiche dell’oggetto di studio. Il rilievo fotogrammetrico è stato svolto mediante l’utilizzo di un drone con equipaggiamento multisensoriale, termico e digitale, su una porzione di territorio soggetto ad anomalie termiche nei pressi di Medolla (MO). Per l’analisi termica e geometrica sono stati posizionati sul campo 5 target termici di cui ne sono state misurate le coordinate per la georeferenziazione delle nuvole dense di punti e la temperatura. In particolare sono state eseguite due riprese aeree dalle quali sono stati estratti i frame necessari per i processi di restituzione fotogrammetrica. Le immagini sono state sottoposte ad una fase di trattamento che ha prodotto immagini rettificate prive di delle distorsioni impresse dall’obbiettivo. Per la creazione degli elaborati vettoriali e raster a colori e termici sono stati impiegati inizialmente software di fotogrammetria digitale in grado di fornire scene tridimensionali georeferenziate dell’oggetto. Sono state sviluppate sia in un ambiente open-source, sia sfruttando programmi commerciali. Le nuvole dense sono state successivamente trattate su una piattaforma gratuita ad interfaccia grafica. In questo modo è stato possibile effettuare dei confronti tra i diversi prodotti e valutare le potenzialità dei software stessi. Viene mostrato come creare un modello tridimensionale, contenente sia informazioni geometriche che informazioni termiche, partendo dalla nuvola termica e da quella a colori. Entrambe georeferenziate utilizzando gli stessi punti fotogrammetrici d’appoggio. Infine i prodotti ottenuti sono stati analizzati in un ambiente GIS realizzando sovrapposizioni grafiche, confronti numerici, interpolazioni, sezioni e profili.

Un nuovo modello computazionale di fibra di Purkinje umana: dal modello medio alla popolazione di modelli e ritorno.

Il lavoro presentato in questa tesi è stato svolto presso il Department of Computer Science, University of Oxford, durante il mio periodo all’estero nel Computational Biology Group. Scopo del presente lavoro è stato lo sviluppo di un modello matematico del potenziale d’azione per cellule umane cardiache di Purkinje. Tali cellule appartengono al sistema di conduzione elettrico del cuore, e sono considerate molto importanti nella genesi di aritmie. Il modello, elaborato in linguaggio Matlab, è stato progettato utilizzando la tecnica delle Popolazione di Modelli, un innovativo approccio alla modellazione cellulare sviluppato recentemente proprio dal Computational Biology Group. Tale modello è stato sviluppato in 3 fasi: • Inizialmente è stato sviluppato un nuovo modello matematico di cellula umana del Purkinje cardiaco, tenendo in considerazione i modelli precedenti disponibili in letteratura e le più recenti pubblicazioni in merito alle caratteristiche elettrofisiologiche proprie della cellula cardiaca umana di Purkinje. Tale modello è stato costruito a partire dall’attuale gold standard della modellazione cardiaca ventricolare umana, il modello pubblicato da T. O’Hara e Y. Rudy nel 2011, modificandone sia le specifiche correnti ioniche che la struttura interna cellulare. • Il modello così progettato è stato, poi, utilizzato come “modello di base” per la costruzione di una popolazione di 3000 modelli, tramite la variazione di alcuni parametri del modello all’interno di uno specifico range. La popolazione così generata è stata calibrata sui dati sperimentali di cellule umane del Purkinje. A valle del processo di calibrazione si è ottenuta una popolazione di 76 modelli. • A partire dalla popolazione rimanente, è stato ricavato un nuovo modello ai valori medi, che riproduce le principali caratteristiche del potenziale d’azione di una cellula di Purkinje cardiaca umana, e che rappresenta il dataset sperimentale utilizzato nel processo di calibrazione.

To land or not to land : How do stakeholders perceive the zero discard policy in European small-scale fisheries?

The authors wish to acknowledge the valuable comments and suggestions made by members of the Committee of Fisheries of the European Parliament. The authors also thank the financial support of the European Parliament (IP/B/PECH/IC/2014–084) and the assistance of Ojama Priit and Marcus Brewer. SV acknowledges the financial support from the Spanish Agency for International Development Cooperation (AECID) (Grant no 11-CAP2–1406) and the Galician Government (Consellería de Cultura, Educación e Ordenación Universitaria, Xunta de Galicia) (Grant no R2014/023). MC acknowledges the financial support from the European Commission through the Marie Curie Career Integration Grant Fellowships – PCIG10-GA-2011–303534 - to the BIOWEB project. CP and GP acknowledge the financial support of Caixa Geral de Depósitos (Portugal) and the University of Aveiro. CP would also like to acknowledge FCT/MEC national funds and FEDER co-funding, within the PT2020 partnership Agreement and Compete 2020, for the financial support to CESAM (Grant no UID/AMB/50017/2013). JMDR and JGC thanks the financial support from the European Commission (MINOW H2020-SFS-2014–2, No 634495) and Xunta de Galicia (GRC 2015/014 and ECOBAS). MA acknowledges financial aid of Xunta de Galicia through Project GPC 2013–045. URS and CP acknowledge the Too Big to Ignore Partnership supported by the Social Sciences and Humanities Research Council of Canada (SSHRC).

Prevalence, Predictors & Prevention of Motion Sickness in Zero-G Parabolic Flights

INTRODUCTION Zero-G parabolic flight reproduces the weightlessness of space for short periods of time. However motion sickness may affect some fliers. The aim was to assess the extent of this problem and to find possible predictors and modifying factors. METHODS Airbus Zero-G flights consist of 31 parabolas performed in blocks. Each parabola consisted of 20s 0g sandwiched by 20s hypergravity of 1.5-1.8g. The survey covered n=246 person-flights (193 Males 53 Females), aged (M+/-SD) 36.0+/-11.3 years. An anonymous questionnaire included motion sickness rating (1=OK to 6=Vomiting), Motion Sickness Susceptibility Questionnaire (MSSQ), anti-motion sickness medication, prior Zero-G experience, anxiety level, and other characteristics. RESULTS Participants had lower MSSQ percentile scores 27.4+/-28.0 than the population norm of 50. Motion sickness was experienced by 33% and 12% vomited. Less motion sickness was predicted by older age, greater prior Zero-G flight experience, medication with scopolamine, lower MSSQ scores, but not gender nor anxiety. Sickness ratings in fliers pre-treated with scopolamine (1.81+/-1.58) were lower than for non-medicated fliers (2.93+/-2.16), and incidence of vomiting in fliers using scopolamine treatment was reduced by half to a third. Possible confounding factors including age, sex, flight experience, MSSQ, could not account for this. CONCLUSION Motion sickness affected one third of Zero-G fliers, despite being intrinsically less motion sickness susceptible compared to the general population. Susceptible individuals probably try to avoid such a provocative environment. Risk factors for motion sickness included younger age and higher MSSQ scores. Protective factors included prior Zero-G flight experience (habituation) and anti-motion sickness medication.

La generazione di modelli tridimensionali densi in ambito architettonico mediante la fotogrammetria digitale

The Italian territory offers a wide range of treasures in the field of Cultural Assets. This is a highly relevant property, which needs an accurate management and preservation performed by appropriate tools, also giving attention to the maintenance and safeguard from risk factors. Nowadays the increasing development of new digital technologies, added by remarkable steps forward got by the subject of Geomatic makes possible an efficient integration among different techniques, helped also by spread of solutions to improve the data import-export and transmission between different devices. The main objective of this thesis is to experience the photogrammetric restitution implemented in a commercial software of digital photogrammetry, in order to generate a dense 3D model of the facade of the Basilica Sant'Apollinare Nuovo in Ravenna. The 1st Chapter, after a general introduction regarding the 3D survey of Cultural Heritage and some considerations linked to the use of digital photogrammetry in this field, is focused to analyze the case of stereoscopic and the monoscopic approach. In particular, it develops the theme of close-range photogrammetry. The 2nd Chapter, exposes the theme of digital images, from color theory until their appearing on the monitor. The 3rd Chapter, develops the case study of the Basilica di Sant'Apollinare Nuovo, the historical, architectural and religious of the same. Also, it is examined the issue of photogrammetry and laser scanning of the case study. The final part of the same chapter, treats the processing of data processing the software Agisoft PhotoScan, in order to generate, by means of Structure from Motion technique, a digital geometric 3D model of the Basilica Facade. The digital model has been scaled on the basis of measurements made on the field. With the software it was possible to accomplish the three phases of the photogrammetric data processing: internal orientation, exterior orientation and restitution.

La sostenibilità dei modelli di business della Sharing Economy: il caso Dimitto.

Questo elaborato ha il fine di approfondire ed esplicitare criticità e leve del sempre crescente fenomeno collaborativo detto Sharing Economy. In appendice il Business Plan della startup Dimitto: progetto svolto durante il corso di Creazione D'Impresa - Riccardo Fini

Schedulazione delle rotte marittime nel settore ortofrutticolo. Modelli e Metodi

Il trasporto marittimo è una delle modalità più utilizzate soprattutto per la movimentazione di grandi volumi di prodotti tra i continenti in quanto è a basso costo, sicuro e meno inquinante rispetto ad altri mezzi di movimentazione. Ai giorni nostri è responsabile di circa l’80% del commercio globale (in volume di carichi trasportati). Il settore del trasporto marittimo ha avuto una lunga tradizione di pianificazione manuale effettuata da progettisti esperti.
 L’obiettivo principale di questa trattazione è stato quello di implementare un modello matematico lineare (MILP, Mixed-Integer Linear Programming Model) per l’ottimizzazione delle rotte marittime nell’ambito del mercato orto-frutticolo che si sviluppa nel bacino del Mediterraneo (problema di Ship-Scheduling). Il modello fornito in questa trattazione è un valido strumento di supporto alle decisioni che può utilizzare uno spedizioniere nell’ambito della pianificazione delle rotte marittime della flotta di navi in suo possesso. Consente di determinare l’insieme delle rotte ottimali che devono essere svolte da un insieme di vettori al fine di massimizzare il profitto complessivo dello spedizioniere, generato nell’arco di tempo considerato. Inoltre, permette di ottenere, per ogni nave considerata, la ripartizione ottimale della merce (carico ottimale).