386 research outputs found
L'energia solare
No full textCome limitare l'impatto dei consumi di energia sull'uomo e sull'ambiente, senza compromettere lo sviluppo economico? Un impiego delle fonti rinnovabili, e in particolare dell'energia solare, è ormai ritenuto necessario e possibile, anche in ampie proporzioni. Nel volume si discutono gli aspetti tecnologici ed economici dello sfruttamento dell'energia solare e si offre un quadro delle politiche nazionali e dell'Unione europea nel settore. Infine, si passano in rassegna alcuni scenari di sviluppo di questa fonte di energia che crescerà molto prima e sarà più a buon mercato di quanto oggi si creda
Technical and economical analysis of an induced demand in the photovoltaic sector
No full textWe analyse the potential economic impact of a demand of photovoltaic (PV) devices in Morocco, in terms of induced production and job creation. In Morocco a high potential for PV installations exists as proved by the number of national and international deployment initiatives currently underway. In our study, we first describe the manufacturing process providing as final output the solar modules and associate the corresponding costs to each step of the process. These costs are needed to determine the technical coefficients of an ad hoc PV sector to be added to the Morocco Leontief matrix. Then, using the input–output methodology, we evaluate the economic impact of the production of 5 MWp modules a year under different hypotheses. A production of 5MWp PV modules, which require an overall investment of h16.3 millions, increases production of h57.6 millions if cells are locally produced and of h22.3 millions when the cells are imported, creating 2570 and 489 jobs, respectively. These results outline the importance of availability of intermediate inputs in local economical context
Infected pseudoaneurysm after carotid endarterectomy: mismatch between clinical presentation and origin
No full textRole of glycemia in acute spinal cord injury: data from a rat experimental model and clinical experience.
No full textWhile experimental and clinical evidence indicates that in brain injury blood glucose increases with injury severity and hyperglycemia worsens neurological outcome, the role of blood glucose in secondary mechanisms of neuronal damage after acute spinal cord injury has not yet been investigated. Data from spinal cord ischemia models suggests a deleterious effect of hyperglycemia, likely due to enhanced lactic acidosis, which is primarily dependent on the amount of glucose available to be metabolized. The purpose of this study is to summarize preliminary experimental and clinical observations on the role of blood glucose in acute spinal cord injury. Between 1995 and 1996 we used the New York University (NYU) rat spinal cord injury model to test the following hypotheses: 1) Blood glucose levels increase with injury severity. 2) Fasting protects from hyperglycemia and prevents secondary damage to the spinal cord. 3) Postinjury-induced hyperglycemia (dextrose 5% 2 gm/Kg) enhances spinal lesion volume. From a clinical perspective, we reviewed blood glucose records of 47 patients admitted to the Department of Neurosrgery in Verona, between 1991 and 1995, within 24 hours of acute spinal cord injury in order to determine: a) the incidence of hyperglycemia (> 140 mg/dl); b) the correlation between blood glucose and injury severity; and c) the role of methylprednisolone in affecting blood glucose. Results indicate that in a graded spinal cord injury model: 1) Early after injury, more severe contusions support significantly higher blood glucose levels. 2) Fasting overnight does not directly affect spinal cord lesion volume but influences blood gases, and we observed that a slightly systemic acidosis plays a minor neuroprotective role. Fasting also ensures more consistent normoglycemic baseline blood glucose values. 3) Postinjury-induced moderate hyperglycemia (160-190 mg/dl) does not significantly affect spinal cord injury. In the clinical study, we observed that during the first 24 hours after spinal cord injury: a) Glycemia ranges between 90 and 243 mg/dl (mean value 143 mg/dl), and close to 50% of the patients present blood glucose values higher than normal. b) Methylprednisolone administration is not associated to significantly higher blood glucose levels. c) There is a trend for larger glucose rises with more severe injury
Geometric and Optic Characterization of a Hemispherical Dome Port for Underwater Photogrammetry
No full textThe popularity of automatic photogrammetric techniques has promoted many experiments in underwater scenarios leading to quite impressive visual results, even by non-experts. Despite these achievements, a deep understanding of camera and lens behaviors as well as optical phenomena involved in underwater operations is fundamental to better plan field campaigns and anticipate the achievable results. The paper presents a geometric investigation of a consumer grade underwater camera housing, manufactured by NiMAR and equipped with a 7'' dome port. After a review of flat and dome ports, the work analyzes, using simulations and real experiments, the main optical phenomena involved when operating a camera underwater. Specific aspects which deal with photogrammetric acquisitions are considered with some tests in laboratory and in a swimming pool. Results and considerations are shown and commented
Il quartiere Olivetti sul lago Fusaro: la ricerca di una nuova dimensione d’abitare
No full textLa Fabbrica Olivetti di Pozzuoli è la più famosa architettura industriale italiana del
Novecento e l’opera più conosciuta di Luigi Cosenza. Meno noto, invece, è che
la Fabbrica era parte di un più ambizioso programma di investimenti nei Campi
Flegrei da parte dell’azienda di Ivrea che comprendeva anche la realizzazione
di un grande quartiere per gli operai sul lago Fusaro e un centro di ricerca e
formazione. I progetti sono l’esito del fortunato incontro di due personaggi
straordinari della cultura italiana del dopoguerra, Adriano Olivetti e Luigi Cosenza,
che condividevano, ciascuno nel proprio ambito di competenza, la capacità
di concepire strategie di ampio respiro restando realisticamente ancorati alle
condizioni del momento.
Il saggio affronta per la prima volta lo studio di questo importante progetto urbano rimasto purtroppo irrealizzato con il supporto di materiali inediti d'archivio e proponendo un confronto con alcuni dei principali quartieri italiani del periodo, allo scopo di evidenziarne i numerosi aspetti di originalità
Innovative Approach for Selection of Pump as Turbine in Water Distribution Network
No full textWhile pressure reducing valves (PRVs) have been widely used in water distribution networks (WDNs) to reduce water leakage, research in recent years has focused on the use of turbines instead of PRVs as the means for enabling both pressure reduction and energy production. However, in WDNs daily continuous variability of flow discharge and upstream head make PAT selection a challenging issue. The present paper describes an innovative approach for optimal PAT selection in systems with hydraulic and/or electrical regulation. The methodology was also applied to a district of the Benevento, Italy, WDN, showing the effectiveness of the proposed approach. The findings showed the optimal pumps lie in the vicinity of the maximum of the produced energy. Furthermore, considering weekday pattern instead of long-period pattern gives reliable results only if the PAT system operated with hydraulic regulation
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