About Piero Matematico (CD)

Daniela Gentilin and Ennio Bettanello reflect on the realization of their project for the CD Piero Matematico.     

A survey of the current photovoltaic equipment industry in Brazil

The use of renewable alternative sources of energy in the world has been growing in the last few decades due to concerns about dependence on fossil sources and to environmental reasons, related to climatic change and its effects on mankind. Tax and/or financial incentives have been instituted for the population, to have access to renewable source technologies, and for the local equipment industry, to develop more quickly. In Brazil, the PV (photovoltaic) equipment to convert solar into electricity is more often used in low income rural communities, located distant from the grid network, for rural electrification, water pumping and public illumination. However, since there is no currently specific regulatory incentive mechanism for this source in the country, the Brazilian PV equipment industry has not made great advances and the market is largely dominated by multinationals. Against this background, a survey of the current PV equipment industry in Brazil is extremely relevant, especially in the event of a national program development to promote the use of this technology, stimulate the domestic industry and reduce the dependence on imported equipment.     

A non-linear analysis to detect the origin of PM10 concentrations in Northern Italy

This work presents the formalization and the application of the factor separation technique in order to investigate the impact of precursor emission and their nonlinear interaction (in particulate matter accumulation processes). By processing the simulations of a 3D multiphase modeling system, the factor separation methodology can support the Environmental Authority in quantifying the impact of precursor emissions on PM10 production and consequently in assessing the feasible efficiency of different emission control strategies over a considered domain. The case study proposed by this paper focuses on the Po Valley region (Northern Italy), characterized by critical PM10 levels claiming for sound emission reduction policies. The results show the heavy nonlinearities and the strong seasonal dependence in the formation of PM10, over the study domain. Furthermore the results highlight that peak PM10 concentrations are mainly related to primary PM emissions in urban areas, and gas emissions (mainly NOx and NH3) in rural areas.     

Effect of laser microcutting on thermo-mechanical properties of NiTiCu shape memory alloy

The machining of shape memory alloys (SMAs), such as NiTi based alloys, is a very interesting and relevant topic for several industrial applications in the biomedical, sensor and actuator fields. Laser technology is one of the most suitable methods for the manufacturing of products in the aforementioned fields, mainly when small and precise features have to be included. Due to the thermal nature of this process, study of its effect on the functional properties of these materials is needed. Except for binary NiTi, few results on the laser machining of NiTi based alloys are available in the literature. In this work, thin sheets of Ni40Ti50Cu10 (at.%) were processed by a fibre laser and the effect of process speed on the material properties was analysed. Scanning electronic microscopy was adopted for observation of the laser cut edges’ morphology. Chemical composition of the processed material was evaluated by energy dispersion spectroscopy and nanohardness measurements were used to estimate the heat affected zone. SMA functional properties were studied on both base and laser machined material. These characteristics are affected by laser machining for the presence of melted material; this effect can be minimised by increasing the laser process speed.     

Impact of changes in the environment on vector-transmitted diseases]

Achalasia, diffuse esophageal spasm, and nutcracker esophagus constitute the main primary esophageal motility disorders. During the past decade major progress has been made in understanding their pathophysiology and in the ability to establish a precise diagnosis. In addition, minimally invasive surgical intervention has radically changed the therapeutic approach, and thoracoscopic or laparoscopic myotomy is probably the best treatment for most patients.     

Li-Fraumeni syndrome in pediatric patients with soft tissue sarcoma or osteosarcoma

Family history of cancer and features of the Li-Fraumeni syndrome (LFS) were investigated in 42 patients with soft tissue sarcoma or osteosarcoma in a pediatric hospital in Mexico City, and compared with 42 non-cancer children. Six subjects with cancer were found among 204 first-degree relatives of cancer patients while there were none among 183 first-degree relatives of non-cancer children. In three families, the proband had two affected relatives, and the type of neoplasia as well as the age of onset suggested the clinical diagnosis of LFS. Our results show that 7.1% of our pediatric patients with soft tissue sarcoma or osteosarcoma may belong to LFS families. The authors encourage pediatric and adult oncologists to pay more attention to the history of cancer in nuclear families for eventual hereditary cancer syndrome identification and cancer prevention.     

Alternative approaches to trip distribution modelling: A retrospective review and suggestions for combining different approaches

Abstract.  Various alternative approaches are available in the literature for modelling trip distribution. The objective of this paper is to provide a review of this literature with the view of summarising the general nature of the current state of practise and what is now available for practical modelling work. Both aggregate and disaggregate destination choice models are considered, a classification of them will be proposed and suggestions for further research will be given as well. One outcome of this review is that significant contributions are emerging from mixed models (e.g., gravity-opportunity, random utility, intervening opportunities models, etc). In particular, the review will highlight the benefit of integrating different approaches like the introduction of intervening opportunities factors within random utility models.     

Generalized Constructive Model of Hysteresis

We describe a generalized constructive model of rate independent scalar hysteresis. It consists of an algorithm that uses a set of experimental hysteresis minor loop vertical chords. The introduced model requires new, less constraining properties than the congruency and equal vertical chords properties required by the classical and the generalized Preisach models. Our model allows for fitting transition curves of order greater than two, despite its simple mathematical notation. Further, we describe interesting performance of the model in numerical evaluation and inversion     

Use of a toasted durum whole meal in the production of a traditional Italian pasta: chemical, mechanical, sensory and image analyses

The characterisation of traditional Italian pasta obtained by mixing amounts of toasted whole meal with re-milled semolina and other ingredients was obtained by means of physico-chemical, rheological, mechanical, sensory and image analyses. The toasted meal showed higher ash, fibre and protein contents than re-milled semolina. The replacement of percentages of re-milled semolina with the toasted meal and soft flour increased tenacity and decreased extensibility and strength, making the dough less suitable for pasta-making. The P / L values were indices of high starch damage. The replacement of part of re-milled semolina and water with toasted whole wheat meal, soft flour and eggs increased the optimal cooking time and the amount of water absorbed during cooking but made the other cooking parameters worse. The image analysis provided evidence of the changes induced by the use of toasted wholemeal, soft flour and eggs in the microscopic structure of pasta protein and starch.