1,720,970 research outputs found
Mappe di scuotimento e stima della magnitudo da momento in tempo reale nell’area delle Alpi sud-orientali.
No full textSource modelling of the Kozani and Arnea 1995 events with strong motion estimates for the city of Thessaloniki.
No full textWe first estimate the source parameters related to the two 1995 events near Thessaloniki (Greece):
the Kozani (Ms = 6.6) and the Arnea (Ms = 5.8) earthquakes. We use the strong motion waveforms
recorded in Northern Greece to retrieve by forward modeling the source characteristics of the two
events. Both point-source and finite-source models are used and different 1-D velocity models
tested. Due to the absence of absolute timing of most of the recordings, the modeling is limited to fitting
the peak acceleration (PA) at different frequencies at the bedrock stations. The best results in
terms of PA are obtained with the finite-source models for a two-asperity k-square distribution. The
source model for the Kozani event is compatible with the main fault proposed by Hatzfeld et al.
[1997]. Given the two source models, we estimate the strong ground motion that would have been
recorded due to these two events at different sites within the city of Thessaloniki. We estimate the
strong ground motion by convolving the synthetic bedrock signals at the sites with 1-D and 2-D
amplification curves obtained for the same sites during previous studies. Our analysis indicates
which of the ten sites are the one most prone to strong shaking and confirms that the most crucial
source parameter to be considered in ground shaking models is the rupture directivity
Mappe di scuotimento del suolo in tempo reale e quasi-reale nell’area delle Alpi Sud Orientali: calibrazione e validazione.
No full textStime dello scuotimento in tempo reale e quasi-reale per terremoti significativi nell’area delle Alpi Sud-Orientali.
No full textNear-real-time damage estimation for buildings based on strong-motion recordings: An application to target areas in northeastern italy
Full text linkThe rapid estimation of expected impacts in case of an earthquake is extremely important for emergency managers and first responders. Current near-real-time damage assessment methods rely on ground-motion estimates and exposure or fragility datasets, in some cases integrating the shaking recorded at the site (e.g., from strong-motion monitoring networks). We propose a method that estimates the expected damages on buildings based on strong-motion recordings of a seismic event. The damage assessment is based on themaximumdrift (interstory) or the displacement, which is estimated by considering in a first approximation the behavior of a specific building typology as a single-degree-offreedom oscillator. The oscillator is characterized based on the analysis of the building stock and a large number of ambient vibration measurements performed in buildings. A specific damage state occurs when the interstory drift or displacement limits available in the literature for the specific building typology are exceeded. The method, here applied to a case study in northeastern Italy, can be applied to other seismic areas worldwide to provide quick, first-level estimates of expected damage
Fast MW estimation of microearthquakes recorded around the underground gas storage in the Montello-Collalto area (Southeastern Alps, Italy)
Full text linkUnderground fluid injection and extraction is able to change pore fluid pressure at depth and make faults unstable, due to friction-force reduction, with an increased possibility of triggering earthquakes. Studying the local seismicity, down to microearthquakes, and stress field in areas where such activities are developed are essential steps to discriminate between natural and induced events. In this context, the moment magnitude (MW) is a key-parameter to both evaluate the energy balance and the stress involved in earthquake rupture process and assess seismic hazard accurately. Here, we focus on the fast MW estimation of microearthquakes recorded around the underground gas storage of Collalto (Northeastern Italy) by a dedicated seismic monitoring network. The area of Montello-Collalto, where this industrial activity is carried out, is densely populated and characterized by relevant seismic hazard. We compute MW from the response spectra (SA) calculated at fixed periods (i.e., 1.0 and 0.3 s); we show that log (SA) and MW scale as 2/3 and extend our method to microseismicity by using response spectra at 0.1 s. We eventually estimate MW for 1659 events (0.4 ≤ MW ≤ 3.5) and find that ML and MW scale as 2/3 too. The discrepancy between these two magnitude scales affects both the Gutenberg-Richter parameters and completeness magnitude estimations; therefore, it has consequences when those quantities are used for physical interpretation. Our procedure shows to be efficient and suitable to be implemented within standard routine analyses of real-time monitoring and feed decision-making processes about plant management, such as the traffic light protocols
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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