Photovoltaic Pumps: Technical and Practical Aspects for Applications in Agriculture

The paper deals with a series of tests conducted on a PV-DC pump in Viterbo (42°24′ North, 12°06′ East). The tests lasted from January 2003 up to November 2004 and involved measurements of solar radiation, on both a horizontal surface and the tilted module surface, flow rates, volumes, and total dynamic heads. In total, up to 3000 data were collected every day whose analysis allowed us to find empirical relationships among system efficiencies, solar radiations, and total dynamic heads. In the second part of the paper we develop a simple method that allows both the assessment of performances of the whole system when installed in a different site from that in which the tests were performed and the optimal inclination angle of the panel to be determined in relation to annual or seasonal use (see irrigation)

“Cape Fear”—A Hybrid Hillslope Plot for Monitoring Hydrological Processes

Innovative experimental field designs and methods are instrumental for dissecting hydrological processes in hillslopes. However, experimental studies at the catchment scale are rarely affordable to most research groups, and laboratory flumes are oversimplified to reproduce natural phenomena. In this work, we present the innovative “hybrid” experimental plot of Cape Fear, which features controllable water fluxes and boundary conditions, but it is directly exposed to external atmospheric agents. We demonstrate the suitability of Cape Fear to study hydrological phenomena through a feasibility test, whereby the response of the plot to a natural storm is in line with the well-known hydrological response of natural hillslopes. Future studies will address the influence of the plot geometry parameters on rill formation

The impact of xylem geometry on olive cultivar resistance to Xylella fastidiosa: an image‐based study

Xylella fastidiosa is a xylem-limited plant pathogen infecting many crops globally and is the cause of the recent olive disease epidemic in Italy. One strategy proposed to mitigate losses is to replant susceptible crops with resistant varieties. Several genetic, biochemical and biophysical traits are associated to X. fastidiosa disease resistance. However, mechanisms underpinning resistance are poorly understood. We hypothesize that the susceptibility of olive cultivars to infection will correlate to xylem vessel diameters, with narrower vessels being resistant to air embolisms and having slower flow rates limiting pathogen spread. To test this, we scanned stems from four olive cultivars of varying susceptibility to X. fastidiosa using X-ray computed tomography. Scans were processed by a bespoke methodology that segmented vessels, facilitating diameter measurements. Though significant differences were not found comparing stem-average vessel section diameters among cultivars, they were found when comparing diameter distributions. Moreover, the measurements indicated that although vessel diameter distributions may play a role regarding the resistance of Leccino, it is unlikely they do for FS17. Considering Young–Laplace and Hagen–Poiseuille equations, we inferred differences in embolism susceptibility and hydraulic conductivity of the vasculature. Our results suggest susceptible cultivars, having a greater proportion of larger vessels, are more vulnerable to air embolisms. In addition, results suggest that under certain pressure conditions, functional vasculature in susceptible cultivars could be subject to greater stresses than in resistant cultivars. These results support investigation into xylem morphological screening to help inform olive replanting. Furthermore, our framework could test the relevance of xylem geometry to disease resistance in other crops

Valutazione della sostenibilità energetica attraverso l’analisi morfotipologica dello spazio urbano

Tra le sfide per l’ambiente urbano che l’Unione Europea ha lanciato (EESC, 2010, URBACT, 2015), compaiono sia la riqualificazione degli spazi pubblici, delle aree verdi e dei sistemi insediativi, sia la riduzione dei consumi energetici, come strumenti per assicurare lo sviluppo sostenibile delle città e aree urbane. L’interesse al tema della rigenerazione urbana, entrato nell’agenda europea da oltre 25 anni, è diventato cruciale e non più orientato alla sola riqualificazione “estetica” della città, ma viene oggi rivolto anche ad altri interventi di natura culturale, sociale, economica ed ambientale, imprescindibili e improcrastinabili per il buon esito del processo rigenerativo. Una delle politiche di intervento che dovrebbe connotare i processi di rigenerazione urbana, corrispondente agli indirizzi comunitari, è certamente quella finalizzata alla riqualificazione energetica dell’edificato. Con l’obiettivo di produrre un supporto informativo utile ai decisori pubblici per apprezzare la fattibilità di implementazione di politiche orientate in tal senso, in un dato ambito territoriale, nel lavoro vengono riassunti i primi risultati ottenuti dalla definizione e implementazione di una metodologia di valutazione della possibilità di utilizzazione delle coperture degli edifici per la produzione di energia sfruttando l’irraggiamento solare

Quali-quantitative Methods for Analyzing Urban Structure and Supporting Regeneration Policies

This study focuses on a method based on the morphological-typological analysis of urban settlements, where some qualitative-quantitative indicators are identified. These indicators compare the metrics of the buildings with their conservation status, in order to gain useful information concerning the needs and potential strategy of intervention and provide an overall picture of the state of deterioration of urban aggregates (such as architecture, structure, and energy usage). Further, they allow for a first economic estimate of the regeneration of the entire urban space. The study occurred in the district of Villa Adriana in Tivoli (Rome), which due to its almost spontaneous origin, suits well the application and validation of the proposed method. The method has potential to address all the functional, urban, and territorial deficiencies in order to spread space regeneration

The flat area issue in DEMs and its consequences on the rainfall-runoff modeling

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L’analisi morfotipologica dello spazio urbano a supporto della formulazione di politiche diffuse di riqualificazione

The growing demand for architectural, environmental and functional quality in the city pushes the experts to devise new tools to meet these needs. Until now, the traditional planning programs, based on the involvement of multiple operators and the participation of public and private resources, have not achieved great results, as directed to limited areas of the city. This paper aims to propose a "simple tool", however, useful to public administrations, to formulate common strategies of interventions, as a response to the demand for urban regeneration. The territorial scope chosen as the testing ground of the feasibility of this new tool is the district of Villa Adriana in Tivoli (RM). In this area, in fact there are all functional, urban and territorial deficiencies that the new instrument would fill with a widespread redevelopment of public space and private ones

Verification of empirical formulas for calculating annual peak flows with specific return period in upper Vistula basin

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