Development and Validation of a Model-Based Combustion Controller for Water Injection Management

This manuscript reports the overall development of a Ph.D. research project during the “Mechanics and advanced engineering sciences” course at the Department of Industrial Engineering of the University of Bologna. The project is focused on the development of a combustion control system for an innovative Spark Ignited engine layout. In details, the controller is oriented to manage a prototypal engine equipped with a Port Water Injection system. The water injection technology allows an increment of combustion efficiency due to the knock mitigation effect that permits to keep the combustion phasing closer to the optimal position with respect to the traditional layout. At the beginning of the project, the effects and the possible benefits achievable by water injection have been investigated by a focused experimental campaign. Then the data obtained by combustion analysis have been processed to design a control-oriented combustion model. The model identifies the correlation between Spark Advance, combustion phasing and injected water mass, and two different strategies are presented, both based on an analytic and semi-empirical approach and therefore compatible with a real-time application. The model has been implemented in a combustion controller that manages water injection to reach the best achievable combustion efficiency while keeping knock levels under a pre-established threshold. Three different versions of the algorithm are described in detail. This controller has been designed and pre-calibrated in a software-in-the-loop environment and later an experimental validation has been performed with a rapid control prototyping approach to highlight the performance of the system on real set-up. To further make the strategy implementable on an onboard application, an estimation algorithm of combustion phasing, necessary for the controller, has been developed during the last phase of the PhD Course, based on accelerometric signals.

On land management: landowners' attitudes to land and farming in Valdera, Tuscany

This thesis aims at explaining the intersecting dynamics of structural changes in agriculture and urbanisation, which involves changes in urban-rural relationships. The research questions are: how and why do landowners differ in their attitudes to land and farming? what are the main implications on rural landscapes and the policy implications? Relationships between urbanisation and agriculture are firstly analysed through a critical literature review; the analysis focuses on the 'landowner' as the key actor who actively takes decisions on the rural landscape From the empirical study – which is based on a Tuscan area (Valdera), and addressed through qualitative methods – a great diversity of landowners' attitudes to land and farming emerge, thus contributing to the agricultural restructuring, such as: 1) the emphasis on recreational function of the countryside for urban people 2) contracting out of land management, especially when landowners live or/and have 'urban' employment 3) the active role of hobby farmers in land management 4) agricultural operations simplification and lack of investments (especially in case of property rights expropriation). The thesis is framed in three papers, with the same methods and research questions. It seems evident that rural landscapes is subjected to functional changes (e.g. residential) and structural changes (landscape polarisation), which requires the need 1) to consider that rural landscape management is increasingly less connected to agricultural production as economic activity; 2) to give a coherence to the range of policy interventions (physical planning, landscape, sectoral).

Operational research applied to regional healthcare system

In this thesis we focus on optimization and simulation techniques applied to solve strategic, tactical and operational problems rising in the healthcare sector. At first we present three applications to Emilia-Romagna Public Health System (SSR) developed in collaboration with Agenzia Sanitaria e Sociale dell'Emilia-Romagna (ASSR), a regional center for innovation and improvement in health. Agenzia launched a strategic campaign aimed at introducing Operations Research techniques as decision making tools to support technological and organizational innovations. The three applications focus on forecast and fund allocation of medical specialty positions, breast screening program extension and operating theater planning. The case studies exploit the potential of combinatorial optimization, discrete event simulation and system dynamics techniques to solve resource constrained problem arising within Emilia-Romagna territory. We then present an application in collaboration with Dipartimento di Epidemiologia del Lazio that focuses on population demand of service allocation to regional emergency departments. Finally, a simulation-optimization approach, developed in collaboration with INESC TECH center of Porto, to evaluate matching policies for the kidney exchange problem is discussed.

Strategic decision making in international firms: effect of top management team internationalization on international strategic decision process

In this research project, I have integrated two research streams on international strategic decisions making in international firms: upper echelons or top management teams (TMT) internationalization research and international strategic decision making process research. Both research streams in international business literature have evolved independently, but there is a potential in combining these two streams of research. The first empirical paper “TMT internationalization and international strategic decision making process: a decision level analysis of rationality, speed, and performance” explores the influence of TMT internationalization on strategic decision rationality and speed and, subsequently, their effect on international strategic decision effectiveness (performance). The results show that the internationalization of TMT is positively related to decision effectiveness and this relationship is mediated by decision rationality while the hypotheses regarding the association between TMT internationalization and decision speed, and the mediating effect of speed were not supported. The second paper “TMT internationalization and international strategic decision rationality: the mediating role of international information” of my thesis is a simple but logical extension of first paper. The first paper showed that TMT Internationalization has a significant positive effect on international strategic decision rationality. The second paper explicitly showed that TMT internationalization affect on international strategic decision rationality comes from two sources: international experience (personal international knowledge and information) and international information collected from managerial international contacts. For this research project, I have collected data from international software firms in Pakistan. My research contributes to the literature on upper echelons theory and strategic decision making in context of international business and international firms by explicitly examining the link between TMT internationalization and characteristics of strategic decisions making process (i.e. rationality and speed) in international firms and their possible mediating effect on performance.

Sviluppo e caratterizzazione microstrutturale e meccanica di leghe innovative di magnesio

Le attività di ricerca svolte nel corso del dottorato di ricerca, sono state focalizzate principalmente sullo studio dell’evoluzione microstrutturale, delle proprietà meccaniche e tribologiche di una particolare lega da fonderia, EV31A, con alte percentuali di terre rare (Nd e Gd > 4% in peso). Le analisi microstrutturali sono state eseguite tramite microscopia ottica (OM), elettronica in scansione (SEM) ed elettronica in trasmissione (TEM), mentre le proprietà meccaniche sono state determinate attraverso prove di trazione e prove di fatica a flessione rotante. Al fine di incrementare le proprietà tribologiche delle leghe di magnesio è stata valutata l’efficacia del trattamento PEO sia sulla lega EV31A, sia sulle più comuni leghe AZ80 e AZ91D, effettuando test tribologici in modalità pattino su cilindro (Block on Ring). Infine è stato condotto uno studio sull’efficacia del trattamento di fusione superficiale laser (LSM), analizzandone gli effetti sia sull’evoluzione microstrutturale, sia sulle proprietà meccaniche e sulla resistenza a corrosione. Le attività svolte nel corso del dottorato di ricerca sono state svolte presso il Dipartimento di Ingegneria Industriale DIN della Scuola di Ingegneria e Architettura dell’Università di Bologna sotto la supervisione della Prof. ssa Lorella Ceschini.

Development and experimental validation of a knock induced damage model and real-time implementation of model-based strategies to control knock intensity in boosted gasoline engines

This PhD thesis reports the main activities carried out during the 3 years long “Mechanics and advanced engineering sciences” course, at the Department of Industrial Engineering of the University of Bologna. The research project title is “Development and analysis of high efficiency combustion systems for internal combustion engines” and the main topic is knock, one of the main challenges for boosted gasoline engines. Through experimental campaigns, modelling activity and test bench validation, 4 different aspects have been addressed to tackle the issue. The main path goes towards the definition and calibration of a knock-induced damage model, to be implemented in the on-board control strategy, but also usable for the engine calibration and potentially during the engine design. Ionization current signal capabilities have been investigated to fully replace the pressure sensor, to develop a robust on-board close-loop combustion control strategy, both in knock-free and knock-limited conditions. Water injection is a powerful solution to mitigate knock intensity and exhaust temperature, improving fuel consumption; its capabilities have been modelled and validated at the test bench. Finally, an empiric model is proposed to predict the engine knock response, depending on several operating condition and control parameters, including injected water quantity.