Papers by Cristiano Fragassa
Sustainability, Feb 10, 2024
With the growing concerns over environmental degradation and the increasing demand for sustainabl... more With the growing concerns over environmental degradation and the increasing demand for sustainable materials, eco-friendly composites have gained considerable attention in recent years. This review paper delves into the promising realm of seed-based fillers, reinforcements and polysaccharidic matrices in the production of biocomposites that are yet focusing on those seeds, which can be considered industrial process waste. Seeds, with their inherent mechanical properties and biodegradability, which are often the waste of production systems, offer a compelling solution to reduce the environmental impact of composite materials. This paper explores the properties of various seeds considered for composite applications and investigates the processing techniques used to incorporate them into composite matrices. Furthermore, it critically analyzes the influence of seed fillers on the mechanical and physical properties of these eco-friendly composites, comparing their performance with traditional counterparts. The environmental benefits, challenges, and limitations associated with seed-based composites from waste seeds are also discussed, as well as their potential applications in diverse industries. Through an assessment of relevant case studies and research findings, this review provides valuable insights into the outlook of seed-based composites as a sustainable alternative in the composite materials landscape, emphasizing their role in promoting a greener and more responsible approach to materials engineering.
Metals, Feb 7, 2024
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
エンジニアリングセラミックの耐食性とWiederhornおよびEvans方程式による比較評価【JST・京大機械翻訳】
Wear, 2019
3D scanning in the project of foundry tools
La crescente richiesta di qualita, tipica dei moderni processi di produzione fusori, rende forte ... more La crescente richiesta di qualita, tipica dei moderni processi di produzione fusori, rende forte l'esigenza di progettare utensili che siano in grado rifinite cin cura i getti, a tale proposito e stato messo a punto un nuovo processo per la progettazione degli utensili da taglio che affianca ai principi di prototipazione rapida una tecnologia di scansione 3D per l'acquisizione e l'elaborazione delle superfici.
Proceedings on Engineering Sciences, Dec 14, 2023
A linear vibratory feeder is an instrument that uses vibration to "feed" material to a process or... more A linear vibratory feeder is an instrument that uses vibration to "feed" material to a process or machine. It consists of a vibrating frame, an electromagnetic coil, a spring, and a tray or trough for conveying materials. The vibration causes the material to move along the tray or trough, ultimately moving the material to its desired destination. The motion analysis of different linear vibratory feeders was here performed and compared. Numerical modeling and experimental verification were combined in the way to investigate the dynamic response of vibratory feeders and their effect on feed particle accelerations on conveying. A close correspondence between the measured and predicted resonance frequencies was found. This information was conveniently used to improve machine designs.
Una innovazione che crea valore
Verso una adozione consapevole degli strumenti di calcolo
L\u2019utilizzo di strumenti di calcolo avanzati per la risoluzione di problematiche di valenza i... more L\u2019utilizzo di strumenti di calcolo avanzati per la risoluzione di problematiche di valenza industriale rappresenta oramai una consuetudine in un vasto campo di mercati e di applicazioni. Il Metodo agli Elementi Finiti, ad esempio, consente di risolvere in modo approssimato i problemi descritti da equazioni complesse. Questa semplificazione, insieme anche all\u2019aumento continuo nella potenza di calcolo, ha reso disponibile uno strumento nuovo e potente per la comprensione dei fenomeni fisici. Allo stesso tempo, si \ue8 affermato come una tecnica validissima per supportare progettisti ed ingegneri nell\u2019affrontare le loro...
International Journal of Automotive and Mechanical Engineering, Jun 30, 2018
This work investigates an innovative hydro-pneumatic suspension system that was recently develope... more This work investigates an innovative hydro-pneumatic suspension system that was recently developed for possibly enhancing the performance of wheeled road vehicles, particularly motorcycles. The device exhibits a highly non-linear behavior, and in particular a strongly regressive spring rate, due to its architecture (featuring a hydropneumatic spring and a coil spring arranged in series). Multibody models are implemented and simulated for a preliminary assessment of its actual benefits and/or drawbacks with respect to common suspension systems. As a starting point of the research, this work focuses on the in-plane dynamics, and in particular on a condition of straight running at constant speed. The load fluctuations on the rear wheel (grip) as well as the velocity of the suspended mass (comfort) under different road inputs at various speeds are analyzed. The numerical results confirm the hydro-pneumatic suspension system as a promising device.
International Journal for Quality Research, Apr 24, 2022
Advanced models, based on artificial intelligence and machine learning, are used here to analyze ... more Advanced models, based on artificial intelligence and machine learning, are used here to analyze a bikesharing system. The specific target was to predict the number of rented bikes in the Nova Mesto (Slovenia) public bike share scheme. For this purpose, the topological properties of the transport network were determined and related to the weather conditions. Pajek software was used and the system behavior during a 30-week period was investigated. Open questions were, for instance: how many bikes are shared in different weather conditions? How the network topology impacts the bike sharing system? By providing a reasonable answer to these and similar questions, several accurate ways of modeling the bike sharing system which account for both topological properties and weather conditions, were developed and used for its optimization.
Predicting the Temperature-Dependent Tensile properties of Polyphenylsulfone using a Machine learning approach
Composite Structures, Jun 1, 2023
Dieci passi verso una fonderia a impatto zero
Zero Impact \ue8 un concetto molto ambizioso quando si parla di una fonderia. un decalogo di inte... more Zero Impact \ue8 un concetto molto ambizioso quando si parla di una fonderia. un decalogo di interventi proposti dall\u2019universit\ue0 di bologna potrebbe indicare la via da seguire per raggiungere l\u2019 \u201cimpatto zer
La deformazione piroclastica: piastrelle piegate e stampi
La natura eccellente della ceramica non \ue8 in discussione e la sua qualit\ue0 \ue8 tale da cons... more La natura eccellente della ceramica non \ue8 in discussione e la sua qualit\ue0 \ue8 tale da consentirle di giocare un ruolo chiave per l\u2019approdo dell\u2019Italia alla seconda piazza in Europa per surplus manifatturiero da esportazione fuori dall\u2019Ue. Ma il settore soffre le contraddizioni del Paese e gli effetti dell\u2019austerity. Nell'articolo si presenta una tecnologia per la piegatura delle piastrelle da noi studiata e che pu\uf2 portare a grossi cambiamenti di mercato
A nonlinear vibration model of the woodworking bandsaw
In this paper nonlinear vibrations of the Timoshenko beams model supported on the different types... more In this paper nonlinear vibrations of the Timoshenko beams model supported on the different types of supports (simple, simple with flexular spring, fixed as well as its combinations) is set and analyzed. The nonlinear stedy-state response of principal resonance and its stability, as well as critical speeds of such as models are obtained. The numerical example is conducted on the real machine from the woodworking industry.
Producing details in natural fibres
From Design to Production: An Integrated Methodology to Speed Up the Industrialization of Wooden Hulls
Journal of ship production and design, Aug 1, 2017
A new design and construction procedure for manufacturing wooden boats is presented, based on mod... more A new design and construction procedure for manufacturing wooden boats is presented, based on modular, parameterized components produced by computer numerical control (CNC) machining. This semiautomated procedure greatly reduces time requirements for vessel assembly compared with traditional methods and yields similar economic viability to other less sustainable materials such as fibreglass. Starting from computer-aided design drawings, the three-dimensional geometry is optimized considering target functions (resistance, dynamics…). Segmentation of wooden strips and transformation into two-dimensional segments permits to simplify CNC machining, with component borders shaped and tapered for better interconnection. Tool path generation is part of the cutting procedure to achieve the required components with the minimum use of raw materials and operational time. All strips, together with the frame, are manufactured using a 5-axis CNC machining center and finally assembled to produce the first industrialized prototype of wooden boat. Manufacturing in this way represents a significant step toward viable mass production of wooden boats. 1. Introduction The application of modem manufacturing techniques to the production of wooden boats has the potential to revitalize the use a cheap and environmentally sustainable material in the boating industry. Such a consideration is particularly relevant in the current global context of economic downturn and climate change. Historically, the use of wood (as in [Lanapoppi 2000, Howorth 1980]) was phased out in favor of materials that were cheaper and simpler to deal with, such as fiber-reinforced composites and aluminium (Espeut 1983). The use of wood was inherently manual (Fig. 1) and time consuming, leading to lower economic viability. The widespread adoption of fiberglass eventually came due to its superior malleability and strength-to-weight ratio, as well as its potential to reduce manual labor requirements during construction (Fox 2001). Several decades later, the needs of both manufacturers and customers alike have changed. Natural materials, zero-impact boating and embodied energy are now regular subjects of discussion in the literature (Guamán et al. 2015). The use of wood and electric-solar drivetrains are common approaches when striving for a negative carbon footprint (Pommier et al. 2015). Increasing attention on environmental sustainability, together with several recent changes in wood production technology, suggest the necessity for reevaluation of resource use in boatbuilding, with emphasis placed on environmental sustainability.
Il pericolo di un boom economico
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Papers by Cristiano Fragassa