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This paper concerns the structural identification of historical masonry buildings with reference to a case study, which is discussed in detail. The building is located in Southern Italy (Lecce). It has an ancient vaulted roof that is complex and commonly found in old masonry structures. This study takes advantage of extensive historical and structural investigations of the building. Preliminary activities have been conducted to obtain information about the current state of the structure including the geometry, morphology, structural details, material properties, prior interventions, and existing damage. This process was supported by an historical investigation into the conceptual background and construction methods used to build the structure. After the historical investigation, a series of experiments, including dynamic tests, were conducted on a number of the vaults to determine their dynamic response characteristics under operational conditions. A numerical model was also determined. In this paper, the primary dynamic test results and modeling assumptions are reported. Comparisons between numerical and experimental results are discussed. [ABSTRACT FROM AUTHOR]

This paper is primarily devoted to general discussion of HRID (High resolution isentropic diagnosis) model developed by Glasnović (1983) and its vertical time cross-sections used operationally on direct output of forecasting model ALADIN (Aire Limitee Adaptation Dynamique et Development International). HRID is based on polynomial hydrostatic adjustment technique making use of reciprocal value of thermal stability parameter and its higher order derivatives. Since these relations are applied in local points of vertical interpolation, the problem is considered analytically, eliminating the finite difference approximation procedure in layers with different isentropic thicknesses. This paper presents a local 72 hourly ALADIN/HRID forecast for the city of Split, Croatia, at the eastern Adriatic coast, with detailed vertical atmospheric structure indicating the characteristic features of a frontal passage on 2 January 2007. [ABSTRACT FROM AUTHOR]

An analysis of Bošković's early paper concerned with the polar light (aurora borealis) gives an insight into the validity of the mathematical method which the young Bošković applied to significant geophysical phenomena in order to comprehend their nature. Based on the given data, we have examined numerical results about the height of atmosphere and the heights of the auroras which were observed over Europe in 1726 and in 1737. In his text there is not a single mathematical formula. Following his instructions we have derived a formula which may be used to determine the distance of an aurora by observing it from one station. For the assumed aurora model, his method is applicable. We find that described ideas on the physical cause of aurora, conceived in a fluid coming from the sun, have elements of modern knowledge. [ABSTRACT FROM AUTHOR]

A field load testing is an effective method for understanding the behavior and fundamental characteristics of cable-stayed bridges. This paper presents results of the behavior of the reconstructed cable-stayed bridge over river Danube in Novi Sad under test load. The bridge was built between 1976 and 1981and in 1999 was heavily damaged by two Tomahawk missiles. In 2003 process of the reconstruction began and at the end of 2005 Faculty of Civil Engineering, University of Belgrade was invited to test reconstructed bridge structure. The results of static load testing presented herein include displacements, rotations and strains of the 351 m long main span. Vibrations of the bridge were obtained by impact load produced by heavy truck passing the bridge and the time history response of vertical accelerations was recorded. The frequency content of the signals was determined using Fourier transformation and five flexural natural periods were extracted. The geological structure and engineering properties of the soil are also given. A finite element model of the bridge was made and a good agreement is achieved between the experimental and analytical results. These results have shown that the bridge is in the elastic state under the code-specified serviceability load, which indicates that the bridge has adequate load-carrying capacity and can be put safely into service. [ABSTRACT FROM AUTHOR]

The implementation of VGR-stress imaging technique, as a free surface boundary condition, in a (2, 4) staggered grid P-SV wave finite difference (FD) algorithm with a variable size of a grid cell is presented in this paper. VGR is acronym for 'vertical grid-size reduction'. The qualitative and quantitative results confirmed that the effective thickness (ETH) of the first soil layer become less by one-half of the vertical size of a grid cell than the assigned thickness (ATH), if stress imaging technique is used as a free surface boundary condition. The results of various numerical experiments revealed that the stress imaging technique causes significant numerical dispersion of Rayleigh waves and the VGR-stress imaging technique is efficient enough to avoid the same. So, superiority associated with the VGR-stress imaging technique over the well stress imaging technique is that it avoids both the significant numerical dispersion of Rayleigh waves in homogeneous medium and the soil thickness discrepancy. The maximum grid spacing ratio (ratio of largest to smallest size of a grid cell) up to 6.0 did not affect the accuracy of FD algorithm with a variable size of a grid cell. In case of a variable size of a grid cell, the required computational memory and time for a particular basin-edge model was 6.43 and 16.62 times lesser than that required in case of uniform grid. [ABSTRACT FROM AUTHOR]