排序方式： 共有7条查询结果，搜索用时 93 毫秒
1
1.
P. Benetti R. Acciarri F. Adamo B. Baibussinov M. Baldo-Ceolin M. Belluco F. Calaprice E. Calligarich M. Cambiaghi F. Carbonara F. Cavanna S. Centro A.G. Cocco F. Di Pompeo N. Ferrari G. Fiorillo C. Galbiati V. Gallo L. Grandi A. Ianni G. Mangano G. Meng C. Montanari O. Palamara L. Pandola F. Pietropaolo G.L. Raselli M. Rossella C. Rubbia A.M. Szelc S. Ventura C. Vignoli WARP Collaboration 《Astroparticle Physics》2008,28(6):495-507
A new method of searching for dark matter in the form of weakly interacting massive particles (WIMP) has been developed with the direct detection of the low energy nuclear recoils observed in a massive target (ultimately many tons) of ultra pure liquid argon at 87 K. A high selectivity for argon recoils is achieved by the simultaneous observation of both the VUV scintillation luminescence and of the electron signal surviving columnar recombination, extracted through the liquid–gas boundary by an electric field.
First physics results from this method are reported, based on a small 2.3 l test chamber filled with natural argon and an accumulated fiducial exposure of about 100 kg day, supporting the future validity of this method with isotopically purified 40Ar and for a much larger unit presently under construction with correspondingly increased sensitivities. 相似文献
2.
A numerical study on seismic risk assessment of historic masonry towers: a case study in San Gimignano 总被引：1，自引：0，他引：1
Gianni Bartoli Michele Betti Andrea Vignoli 《Bulletin of Earthquake Engineering》2016,14(6):1475-1518
After a brief introduction on the research project RiSEM (Seismic Risk of Monumental Buildings), the paper discusses on the seismic assessment of historic masonry towers according to the Italian “Guidelines for the assessment and mitigation of the seismic risk of the cultural heritage” that identifies an analysis methodology based on three different levels of evaluation, according to an increased knowledge of the structure. The RiSEM project aimed at developing and testing innovative and expeditious methodologies (i.e. either without or with a minimal direct contact with the masonry building) to evaluate all the main structural features of the monumental buildings required for the assessment of their seismic safety. As a relevant case study the “Town of Fine Towers”, San Gimignano (Italy), listed under the UNESCO World Cultural Heritage Sites, was selected. The paper summarizes the analyses performed on one of the San Gimignano towers: the Coppi-Campatelli one. The seismic vulnerability of the tower was evaluated with reference to the above guidelines, and the paper reports and critically compares the results obtained for the three levels of evaluation there defined: LV1 (analysis at territorial level), LV2 (local analysis) and LV3 (global analysis). 相似文献
3.
Micòl Mastrocicco Giulio Vignoli Nicolò Colombani Nasser Abu Zeid 《Environmental Earth Sciences》2010,61(2):311-322
A portion of an unconfined alluvial aquifer located in the Padana Plain (Italy) was characterized following an integrated
hydro-geophysical approach. Initially an electrical resistivity tomography (ERT) survey was employed to localize the boundaries
of a modest paleo-channel body and to design the installation of a groundwater monitoring network. Multilevel slug-tests were
performed to estimate the aquifer’s saturated hydraulic conductivities. Determined permeability values together with electrical
resistivity data were correlated. The correlation resulted in a site specific bi-logarithmic linear relationship. Based on
this relationship, punctually determined hydraulic conductivities were spatially extended over the studied flow domain. Finally,
continuously measured piezometric heads were used to calibrate a 3D flow model. Sensitivity analysis was performed to confirm
the reliability of the reconstructed permeability field, as well as, to assess the minimum number of direct measurements needed
to safely characterize the selected aquifer portion. The integration of the ERT survey results with the classical hydrogeological
tests can be conveniently applied to constrain the permeability field during flow model calibration. Although the applicability
of the determined relationship is site specific, the followed procedure is useful especially when there is a need to optimize
the available resources and in case of small-scale pilot studies. 相似文献
4.
5.
Deidda Gian Piero Díaz de Alba Patricia Rodriguez Giuseppe Vignoli Giulio 《Mathematical Geosciences》2020,52(7):945-970
Mathematical Geosciences - Frequency-domain electromagnetic instruments allow the collection of data in different configurations, that is, varying the intercoil spacing, the frequency, and the... 相似文献
6.
Surface wave methods are based on the inversion of observed Rayleigh wave phase‐velocity dispersion curves. The goal is to estimate mainly the shear‐wave velocity profile of the investigated site. The model used for the interpretation is 1D, hence results obtained wherever lateral variations are present cannot be considered reliable. In this paper, we study four synthetic models, all with a lateral heterogeneity. When we process the entire corresponding seismograms with traditional f‐k approach, the resulting 1D profiles are representative of the subsurface properties averaged over the whole length of the receivers lines. These results show that classical analysis disregards evidences of sharp lateral velocity changes even when they show up in the raw seismograms. In our research, we implement and test over the same synthetic models, a novel robust automated method to check the appropriateness of 1D model assumption and locate the discontinuities. This new approach is a development of the recent multi‐offset phase analysis with the following further advantages: it does not need previous noise evaluation and more than one shot. Only once the discontinuities are clearly identified, we confidently perform classical f‐k dispersion curve extraction and inversion separately on both sides of the discontinuity. Thus the final results, obtained by putting side by side the 1D profiles, are correct 2D reconstructions of the discontinuous S‐wave distributions obtained without any additional ad‐hoc hypotheses. 相似文献
7.
Frequency‐dependent multi‐offset phase analysis of surface waves: an example of high‐resolution characterization of a riparian aquifer 
下载免费PDF全文
下载免费PDF全文 Giulio Vignoli Isabella Gervasio Giuseppe Brancatelli Jacopo Boaga Bruno Della Vedova Giorgio Cassiani 《Geophysical Prospecting》2016,64(1):102-111
Multi‐offset phase analysis of seismic surface waves is an established technique for the extraction of dispersion curves with high spatial resolution and, consequently, for the investigation of the subsurface in terms of shear wave velocity distribution. However, field applications are rarely documented in the published literature. In this paper, we discuss an implementation of the multi‐offset phase analysis consisting of the estimation of the Rayleigh wave velocity by means of a moving window with a frequency‐dependent length. This allows maximizing the lateral resolution at high frequencies while warranting stability at the lower frequencies. In this way, we can retrieve the shallow lateral variability with high accuracy and, at the same time, obtain a robust surface‐wave velocity measurement at depth. In this paper, we apply this methodology to a dataset collected for hydrogeophysical purposes and compare the inversion results with those obtained by using refraction seismics and electrical resistivity tomography. The surface‐wave results are in good agreement with those provided by the other methods and demonstrate a superior capability in retrieving both lateral and vertical velocity variations, including inversions. Our results are further corroborated by the lithological information from a borehole drilled on the acquisition line. The availability of multi‐offset phase analysis data also allows disentangling a fairly complex interpretation of the other geophysical results. 相似文献
1