3,960 research outputs found
Design spectra to be used in Base Isolation Design in light of recent strong motion records
No full textStrong motion records have shown an increase of the maximum values of PGA and PGV, also associated to the increase of the archived strong motion records. Nowadays, the worldwide largest PGA values are: 3,94g (vertical) and 2,75g (horizontal), from the 2008 Iwate-Miyagi and 2011 Tohoku earthquakes, while the current PGV maxima are larger than 2.0 m/s (horizontal and vertical). These unforeseen values have encouraged a more conscious approach in BIS design, being necessary to move to larger design periods and to face wider design displacements. Many changes have occurred in the history of BIS, as indicated in Design Recommendations for Seismically Isolated Buildings by AIJ (2016), tracing the improvements of BIS in Japan, and in De Luca and Guidi (2019). In this excursion, a significant contribution has been given by Miyazaki (2008) that defined a "Next Generation of seismic isolation" to counteract the unprecedented spectral values of displacement and acceleration. In this perspective, the paper analyzes the acceleration, velocity and displacement spectra of different sets of strong motion records to provide suggestions for seismic design of base-isolated structures in the light of higher spectral values. In particular, we will consider: the set defined in Trevor Kelly (2001), that divided motions into pre-1971 and post-1971; the set of FEMA307 (1999), in which three categories of ground motion are considered (short duration, long duration and forward directivity); the set used by Miyazaki (2008) for the Next Generation of Seismic Isolation; the set defined by Suzuki and Iervolino (2017) to trace the history of largest PGA and PGV; the set used by De Luca and Guidi (2019) to trace the improvements in BIS design and propose a classification of BIS in three successive generations. A comparison between results, for different periods, will lead to possible design indications for BIS
Le traduzioni dei manuali di Luigi Cossa: uno studio bibliografico
No full textIl saggio ricostruisce i dati bibliografici e contestuali di tutte le traduzioni dei manuali di economia politica e scienza delle finanze composti da Luigi Cossa
Base isolation issues in Italy: Integrated architectural and structural designs
No full textThis paper deals with the evolution of base isolation design in Italy, underlining improvements that occurred in the last 30 years, from earliest pioneering cases to recent solutions. They result from an integrated design procedure into which structural and architectural aspects merge harmoniously. Back analysis of existing structures and personal assessment of corresponding data from literature will give the possibility to describe changes occurred in Italian design applications. This paper looks at “all rubber” solution, matching the main design issues: design vibration period, Tiso; design displacement, δ; device diameter, φ; device tributary area, A. Following excursion will underline a quite different design approach, as compared to worldwide trends. Design displacements smaller than 30 cm, accomplished by device diameter in the maximum range of 900 mm–1000 mm, correspond to high vertical stress σ upon devices, up to 9 MPa–10 MPa, and to small vibration periods, not exceeding 3.0 s. In the last part of this paper, recent base isolation solutions, coming from a personal research path [De Luca et al.], will be analysed as result of a newer design approach. These latter cases will show benefits obtained through the increase of device diameters, φ, and corresponding tributary areas, A, combined with the reduction of the number of bearing points. This correspond to the use of on long-spans structural grids that guarantee greater flexibility also in organizing spaces. This underscores base isolation as part of an integrated procedure where freedom in architectural design combines to structural efficiency
An assessment of the impact of possible CAP reform scenarios on Romanian agriculture
No full textUsing a simplified model, with key-variable the prices of two different possible scenarios of CAP reform after 2013 (moderate and radical), this paper present a comparison between the price effects of implementation of each reform scenario at 2015 horizon on Romanian agriculture. This short analysis shows that, under the presented hypotheses, the net welfare effect, due to the price changes, for the selected products, is positive in both reform scenarios, yet greater in the case of the radical reform. Integrated in the large context of Romanian development, it seems that the influence of CAP reform upon agriculture and rural areas will be most likely a gradual one: an interpenetration between the two scenarios is foreseeable, starting with the moderate reform that will dominate the period around 2013, the reform measures acquiring a more radical character afterwards.CAP reform, Romania, welfare effects, Agricultural and Food Policy,
The Debate Concerning the Off-label Prescriptions of Drugs: A Comparison between Italian and U.S. Law
No full textReference intervals as a tool for total quality management
No full textThe more traditional, widespread and practiced method for interpreting the laboratory results is based on the comparison made with reference intervals. Nevertheless, the creation of appropriate reference intervals requires careful planning, monitoring and documentation of every aspect of the study, including the selection of the reference population (encompassing selection of homogeneous groups of reference according to ethnicity, geographical origin and environmental conditions, stratification according to age and gender, definition of health status) along with the use of the most appropriate statistical tools. In the very next future, the longitudinal comparison of laboratory results might probably replace the current use of reference intervals
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