Dynamic analysis of a type of problem arising when lowering a buoy system     

R.O. Grossi  L. Ercoli   《Ocean Engineering》1981,8(3):211-219

The present paper deals with the analysis of a cable system which carries several concentrated masses and is lowered at a constant speed when suddenly the upper end stops. This basic model satisfies a major operational requirement when deploying some types of buoy-cable systems.  相似文献   

Free vibration of rectangular plates with circular openings     

Ricardo O. Grossi  Blanca del V. Arenas  P.A.A. Laura 《Ocean Engineering》1997,24(1):19-24

The optimized Rayleigh-Ritz method is applied to generate values of the fundamental frequency coefficient and the one corresponding to the first fully antisymmetric mode for rectangular plates elastically restrained against rotation and with located circular holes. The results of this study are compared with existing data and the agreement is quite good.  相似文献   

Enargite oxidation: A review     

Pierfranco Lattanzi  Stefania Da Pelo  Elodia Musu  Davide Atzei  Bernhard Elsener  Marzia Fantauzzi  Antonella Rossi 《Earth》2008,86(1-4):62-88

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Using historical maps to analyze two hundred years of land cover changes: case study of Sorrento peninsula (south Italy)     

Stefania Pindozzi  Elena Cervelli  Alessandra Capolupo  Collins Okello 《制图学和地理信息科学》2016,43(3):250-265

Historical maps are effective sources of geographical information and useful for historical and territorial research. In this study, the examination of landscape dynamics on the basis of historical maps over a period of more than 200 years was conducted. The study area is Sorrento peninsula and part of the near Sarno river basin in South Italy. This study provides a general framework for the assessment of the overall quality and accuracy of historical maps. The application of the methodology used in this specific case study can contribute to a better understanding of the dynamics of the landscape in the long term. The derived knowledge can be applied in the planning of the landscape in order to implement correct conservation strategies. The comparison was made on four maps 1817, 1875, 1960, and 2006. Geodetic accuracy of the sheet maps of 1817 and 1875 offer a right basis for a macro analysis of land cover dynamics, evaluating conversion from one land cover category to another. Main transformation, identified in the period between 1875 and 1960, was the disappearance of vineyards, which covered 25% of the total study area in 1875. Agricultural areas increased in this period to cover 57% of the total area.  相似文献   

Galactic gamma halo by heavy neutrino annihilations?     

D. Fargion  R. Konoplich  M. Grossi  M. Khlopov   《Astroparticle Physics》2000,12(4):495-314

The diffused gamma halo around our Galaxy recently discovered by EGRET could be produced by annihilations of heavy relic neutrinos N (of fourth generation), whose mass is within a narrow range (M_Z/2<m_N<M_Z). Neutrino annihilation in the halo may lead to either ultrarelativistic electron pairs whose Inverse Compton Scattering on infrared and optical galactic photons could be the source of observed GeV gamma rays, or prompt 100 MeV–1 GeV photons (due to neutral pion secondaries) born by reactions. The consequent gamma flux (10⁻⁷–10⁻⁶ cm⁻² s⁻¹ sr⁻¹) is well comparable to the EGRET observed one, and it is also compatible with the narrow window of neutrino mass 45 GeV <m_N<50 GeV, recently required to explain the underground DAMA signals.The presence of heavy neutrinos of fourth generation do not contribute much to solve the dark matter problem of the Universe, but may be easily detectable by outcoming LEP II data.  相似文献   

Dowel connections securing roof-diaphragms to perimeter walls in historic masonry buildings and in-field testing for capacity assessment     

Alessandra Marini  Ezio Giuriani  Andrea Belleri  Stefania Cominelli 《Bulletin of Earthquake Engineering》2018,16(9):4001-4025

In the seismic retrofit of existing masonry constructions, global interventions are often needed to inhibit the onset of local mechanisms and to engage the whole building box-like structural behaviour. Such interventions are represented by perimeter ties and roof and floor diaphragms. This paper considers the roof diaphragm strengthening solution and investigates the use of stud connections securing the roof thin-folded shell to the perimeter walls. Stud connections serve the dual purpose of collecting and transferring the out-of-plane inertia forces of the masonry walls to the roof diaphragm, as well as transferring the diaphragm reaction forces to the shear walls. Specific detailing of the stud connection and the adoption of an improved lime-mortar overlay on the top of the masonry walls are proposed to improve the connection strength; without such improvements, the connection capacity would be jeopardised by the reduced shear resistance of the masonry wall due to the absence of significant vertical confining action at the roof level. The intervention entirely changes the behaviour of the connection and significantly reduces shear stresses on the masonry wall. The structural behaviour of the connection is analysed and discussed. Emphasis is made on the conceptual design of laboratory and in-field test procedures and testing frames in order to replicate the boundary conditions in real applications. In-situ tests may help during the design of the roof thin-folded shell system and allow for the efficiency assessment of the connections prior to the final intervention, thereby proving the actual feasibility of the retrofit solution.  相似文献   

Ecotoxicological and human health risk in a petrochemical district of southern Italy   总被引：2，自引：0，他引：2  

Ausili A  Gabellini M  Cammarata G  Fattorini D  Benedetti M  Pisanelli B  Gorbi S  Regoli F 《Marine environmental research》2008,66(1):215-217

An ecotoxicological investigation has been carried in the petrochemical district of Priolo (Sicily, Italy), one of the largest in Europe. Results indicated a severe mercury contamination in sediments sampled near a chloro-alkali plant. A clear bioavailability of this element was demonstrated in mussels Mytilus galloprovincialis (both native and translocated) and the benthic fish Mullus barbatus, which also exhibited marked genotoxic damages. The elevated mercury concentrations in marine organisms are a serious concern for human health; according to the national average fish consumption, the provisional tolerable weekly intake (PTWI) of Hg would be easily exceeded by at least 4 to 12 fold. Such toxicological risk is of particular importance for pregnant women, being possibly involved in the elevated frequency of neonatal malformations.  相似文献   

New geomorphological and chronological constraints for glacial deposits in the Rivoli‐Avigliana end‐moraine system and the lower Susa Valley (Western Alps,NW Italy)          下载免费PDF全文

Susan Ivy‐Ochs  Stefania Lucchesi  Paolo Baggio  Gianfranco Fioraso  Franco Gianotti  Giovanni Monegato  Angela A. Graf  Naki Akçar  Marcus Christl  Francesco Carraro  Maria Gabriella Forno  Christian Schlüchter 《第四纪科学杂志》2018,33(5):550-562

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Modelling the seismic response of a 2-storey URM benchmark case study: comparison among different equivalent frame models     

Manzini  Carlo Filippo  Ottonelli  Daria  Degli Abbati  Stefania  Marano  Corrado  Cordasco  Emilia Angela 《Bulletin of Earthquake Engineering》2022,20(4):2045-2084

Bulletin of Earthquake Engineering - The paper presents the comparison of the results of non-linear static analyses performed with different software based on the equivalent frame (EF) modelling...  相似文献   

Nitrogen and Phosphorus Recovery from Human Urine by Struvite Precipitation and Air Stripping in Vietnam   总被引：1，自引：0，他引：1  

Samantha Antonini  Stefania Paris  Thomas Eichert  Joachim Clemens 《洁净——土壤、空气、水》2011,39(12):1099-1104

A “No Mix” sanitation system was installed in a dormitory at the University of CanTho in South Vietnam, with the objective of recycling nutrients from source separated wastewater streams. This paper presents the “Yellow Water” treatment plant and its efficiency in recovering phosphorus and nitrogen from human urine. The pilot plant achieved phosphorus removal efficiencies of 98% with both diluted and undiluted urine. Phosphorus was recovered in the form of struvite, a solid mineral fertilizer with heavy metal concentrations being below the German Fertilizer Regulation's threshold limits. About 110 g of struvite could be generated after one treatment cycle, during which 50 L of urine were processed. Nitrogen removal by air stripping showed best results when circulating the urine for 3 h through the stripping column at a high flow rate (80 L/h). With these settings, more than 90% of the nitrogen could be removed from the urine, and virtually 100% of this nitrogen could be recovered in the form of liquid ammonium sulfate. In the future, treatment costs could be further reduced by making use of the solar energy that is available during daytime in South Vietnam.  相似文献