805 research outputs found
Moretto and Romanino: religious painting in Brescia 1510-1550: identity in the shadow of La serenissima
No full textThis thesis examines several works of religious content produced by the Brescian painters Gerolamo Romano, 11 Romanino (148487-15'59) and Alessandro Bonvicino, 11 Moretto (1498-1554), produced for patrons and locations in Brescia between 15 10 and 1550. This enquiry has drawn on little used historical material in order to integrate the discussion of the images into a wider social and historical context.
The key aim of this study is to establish how Romanino and Moretto defined a Brescian identity in art. This will be argued by using two different approaches in order to examine the existence, and the manifestations, of such a local identity One approach taken in this study is to look at groups of corporate patrons and to consider the works executed for them in terms of similarities of content. Chapters 2 and 3 in turn consider the works executed by Romanino and Moretto for the Congregations of Santa Giustina of Padua, and of San Giorgio in Alga. The second approach adopted for the purposes of examination of strategies for the establishment of a Brescian visual identity employed in this study is to focus on representations of the Eucharist. It will be shown that Moretto developed a new visual motif of the 'Eucharistic Christ' in response to the growing popularity of the Forty Hours devotion in Brescia
Performance Characterization of Propulsion Systems for Spacecraft Applications
No full textThe subject of the research program described in the present work is the analysis of hybrid rocket motors performance, through different experimental campaigns, which have been conducted on both small scale and full scale versions. The diagnostics system was composed by sensors to measure the pressure levels in many different sections of the propulsion system, sensors to monitor the burned quantity of fuel and oxidizer and sensors useful to define the physical conditions of the used oxidant: liquid nitrous oxide, in auto-pressurization form.
During this experience with chemical propulsion systems at CISAS, various test types have been performed, in order to study all the problematics, which concern the functioning of a hybrid rocket: a) discharge tests, to set-up the hydraulic circuit,
valve actuation and injection of oxidizer; b) ignition tests, to understand the issues that are connected with the initial burning phases; c) hot firing tests, to investigate the behavior of the motor during complete functioning operations.
All the needed instrumentation has been accurately and specifically designed and produced for this scope: the experimental facilities, the test bench, the different versions of the motor subsystems. A huge amount of work has been done, and it has permitted to verify the effect of many different design solutions on the final performance of the tested rockets.
An initial small scale experimental campaign served as a “test bench” in order to preliminarily verify main issues in the development of chemical propulsion systems, to calibrate the diagnostics and to highlight the initial performance characteristics
of the motor: in particular, the final choice of the fuel grain material has been done in this phase. After that, a first full scale motor version has been designed, using the resulting data of the small scale tests: the analysis on the verified instabilities started from this experimental campaign, in which an unstable behavior has been investigated and assigned to the injection of oxidizer in combustion chamber. For this reason, an accurate research program has been set-up to deep analyse how the fluid enters and behaves prior and after the injection plate: in a dedicated facility, many different injector types have been tested in different discharge conditions, in order to investigate the physical properties of N2O in auto-pressurization form, as it is used in the tested motors. The results of this intermediate program have permitted to upgrade some technical solutions of the rocket design, and improve its performance both in terms of combustion efficiency and instabilities mitigation.
To check the effects on the developed performance, two final verification test campaigns have been carried out, on two different motor versions. This has been useful also in the developing of a real “proto-flight” motor, which adopted lightweight materials and compact configurations: the experimental campaigns have been very useful in the definition of all the stresses, that would affect a possible payload of the produced propulsion system.Oggetto del programma di ricerca è l’analisi delle prestazioni di propulsori ibridi attraverso campagne sperimentali condotte su motori in scala ridotta e completa. Le misure effettuate sono state acquisite attraverso un apposito sistema di diagnostica,
composto da sensori per la misura dei valori di pressione in differenti sezioni del sistema propulsivo, sensori per il monitoraggio delle quantità impiegate di combustibile e comburente, e sensori per definire le condizioni fisiche dell’ossidante: protossido d’azoto auto-pressurizzato.
Durante questa esperienza condotta al CISAS nell’ambito della propulsione chimica, svariate prove sperimentali sono state condotte per studiare le problematiche che concernono il funzionamento di motori ibridi: a) test di scarica ossidante, per la messa a punto del circuito idraulico, del funzionamento della valvola principale e delle prestazioni del sistema di iniezione; b) test di accensione, per investigare le problematiche connesse con le fasi iniziali della combustione; c) test a fuoco, per lo studio del motore durante il completo funzionamento.
Tutta la strumentazione necessaria è stata accuratamente progettata e prodotta con tali finalità: la facility sperimentale, il banco di test e le diverse versioni dei sottosistemi del motore. Una consistente mole di lavoro è stata portata a termine, e ha permesso la verifica degli effetti di diverse soluzioni progettuali sulle prestazioni finali sviluppate dagli endoreattori testati.
Una prima campagna sperimentale su motori in scala ridotta ha servito come “banco prova” per prendere confidenza con i sistemi propulsivi chimici, per la calibrazione della diagnostica e per evidenziare le iniziali caratteristiche prestazionali: in particolare, in questa fase è stata fatta la scelta definitiva del materiale per il grano combustibile. In un secondo momento, una prima versione in scala completa del motore è stata progettata, impiegando i risultati della precedente campagna sul
propulsore in scala ridotta: l’analisi delle instabilità di combustione è iniziata a partire da questa serie di test, nella quale il comportamento instabile è stato studiato e riconosciuto come effetto dell’iniezione di ossidante nella camera di combustione.
Per questo motivo, una precisa fase di studio è stata implementata per analizzare come il fluido si comporta a cavallo della piastra di iniezione: attraverso un set-up sperimentale dedicato, svariati tipi di iniettore sono stati testati in molte configurazioni diverse, nell’ottica di studiare attentamente le proprietà fisiche dell’N2O in condizione auto-pressurizzata, così come è stato impiegato nei test del motore.
I risultati di questa fase intermedia hanno permesso di aggiornare alcune soluzioni tecniche del design del motore, e migliorarne in questo modo le prestazioni sia in termini di efficienza di combustione, sia nell’attenuazione delle instabilità. La verifica degli effetti sulle prestazioni sviluppate è stata effettuata durante due ultime campagne di test, condotte su due diverse versioni del motore. L’utilità di questo lavoro è stato anche quello di sviluppare una realistica versione “pre-volo” del motore, che ha impiegato materiali leggeri e una configurazione compatta: le campagne sperimentali sono state molto utili nella definizione delle sollecitazioni che potrebbero interessare un eventuale payload del sistema propulsivo prodotto
Adoption of additive manufacturing technology: drivers, barriers and impacts on upstream supply chain design
No full textPurpose – This paper investigates how the adoption of additive manufacturing (AM) impacts upstream supply chain (SC) design and considers the influence of drivers and barriers towards the adoption.
Design/methodology/approach – Ten case studies investigating AM adoption by Original Equipment Manufacturers (OEMs) in five industries were conducted. This research is driven by a literature-based framework, and the results are discussed according to the theory of transaction cost economics (TCE).
Findings – The case studies reveal four patterns of AM adoption that affect upstream SC design (due to changes in supply base or types of buyer–supplier relationships): make, buy, make and buy and vertical integration. A make or buy decision is based on the level of experience with the technology, on the AM application (rapid manufacturing, prototyping or tooling) and on the need of control over production. Other barriers playing a role in the decision are the high initial investments and the lack of skills and knowledge.
Originality/value – This paper shows how different decisions regarding AM adoption result in different SC designs, with a specific focus on the upstream SC and changes in the supply base. This research is among the first to provide empirical evidence on the impact of AM adoption on upstream SCs and to identify drivers of the make or buy decision when adopting AM through the theoretical lens of TC
The integration between physical and digital outbound supply chains of Italian fashion companies
No full text
Dynamic capabilities for fashion-luxury supply chain innovation
No full textPurpose: This paper aims at developing a conceptual framework to identify the main features of supply chain innovation and to analyse the role of dynamic capabilities in implementing such innovations in the context of the fashion-luxury industry. Design/methodology/approach: The paper follows an exploratory approach based on one in-depth case study. The theoretical framework, developed through the literature review, is applied to a Italian fashion-luxury company, thus exploring its applicability in a real context and obtaining evidence in the area of supply chain innovation. Findings: The paper offers insights on supply chain innovation, by investigating an area under-explored in the existing literature. The paper provides a conceptual framework oriented to analyse the main features of supply chain innovation for fashion-luxury companies, by investigating the main determinants of innovation. Research limitations/implications: The proposed model provides initial insights into the topic of supply chain innovation in fashion-luxury companies. To date, the analysis is predominantly qualitative and therefore replication is needed to generalise the results. Practical implications: The paper identifies three different perspectives of supply chain innovation and the relationships between supply chain innovation and other types of innovations, which are hopefully useful for managers that are willing to introduce innovation inside fashion-luxury companies. Originality/value: The paper addresses a new topic, underexplored in the supply chain management literature, by considering a peculiar area of investigation, the fashion-luxury. Moreover, the paper investigates the topic of supply chain innovation through the support of empirical data
AI meets spend classification: A new frontier in information processing
No full textThis paper investigates the impact of artificial intelligence (AI) on spend classification in buyer firms, using the organizational information processing theory (OIPT) as a reference framework. Existing research on the use of AI in procurement lacks a holistic approach that effectively integrates human oversight. This gap is particularly evident in procurement activities beyond automating repetitive tasks, especially in advanced analyses supporting strategic purchasing decisions, such as spend classification. Through a case study approach focusing on providers of AI-based spend classification solutions, this research highlights how AI addresses the substantial information processing needs that exceed the internal capabilities of buyer firms. By aligning these needs with the capabilities enabled by the adoption of AI, the study demonstrates a significant advancement in spend classification practices. This research applies the theoretical constructs of the OIPT at the intersection of two relatively unexplored domains—spend classification and AI and aims to translate these constructs into actionable insights for professionals, thereby making a significant contribution to the field
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