Case Study—An Extreme Example of Soil–Structure Interaction and the Damage Caused by Works on Foundation Strengthening

This paper describes the works on foundation strengthening of the towers of the Cathedral of St. Theresa of Avila in Subotica and the damages caused by these works. Strengthening was performed by means of jacked-in piles and deep soil injection. The construction of the Cathedral began in 1773 and it lasted for several decades with frequent interruptions and changes to the project. The present appearance of the facade was created in 1912. According to historic data, several years after construction, the cracks appeared on the front facade. With time, these cracks became more pronounced, and in 2015, when the remediation project started, the total width of major cracks reached about 15 cm. The first contemporary attempt to repair the towers was made in 2017 by inserting piles beneath the foundations. These works were interrupted due to increased settlements and the appearance of new cracks. In the second attempt, the strengthening was performed by deep injection of soil with expansive resins. During these works, settlements and damages intensified even more, causing the works to be halted in 2018. Analysis of the whole structure and revaluation of all the results, obtained from continuous monitoring of settlements and crack widths from the previous period, led to the new remediation proposal. The imperative was to retain the original appearance of the Cathedral facades while performing the total reconstruction of the upper sections of the front facade. This implies that the overall weight of the reconstructed parts is to be decreased, while the strength is to be increased. Strong structural connections are planned, both among the two towers, and between the towers and the nave. These clear structural solutions will lead to reduced stresses within the existing brick walls, reduced contact soil pressures and ceasing of increased settlements and tilting of the Cathedral towers.

Dendrochronological Reconstruction of June Drought (PDSI) from 1731–2016 for the Western Mongolian Plateau

Droughts are a recurrent phenomenon in the semiarid forest-steppe ecotone of Mongolia with negative consequences for tree growth and agricultural management. In order to better cope with the uncertainty of a changing climate, the study of historical drought and its effects on forests could provide useful insights into ecosystem responses to climate variability. Siberian larch (Larix sibirica) is a dominant tree species in Western Mongolia that provides a valuable source of proxy data in the form of annual rings. We used dendrochronological techniques to establish a standard master chronology and analyze the relationship between annual ring widths and climatic factors. Correlation analyses revealed that the strongest associations of tree-ring index (TRI) values for the master chronology to direct climate variables were June temperature (r = −0.36, p < 0.01) and precipitation (r = 0.39, p < 0.01). The master chronology was strongly correlated to Palmer Drought Severity Index (PDSI) for June (r = 0.606, p < 0.001), and this variable (PDSIJun) was chosen for reconstruction. A simple linear regression of PDSIJun based on TRI explained 35.4% of the total variance for the period 1965–2016 and based on this model the PDSIJun changes from 1731–2016 were reconstructed. Split–sample calibration–verification tests were conducted to evaluate the quality of the model used for climate reconstruction. In the past 286 years, the number of non-drought years (PDSI > 0) was low, with a frequency of only 14.1% of the total reconstruction years. Extreme drought (PDSIJun < −2.70) occurred frequently in the 19th and early and late 20th centuries. Multi-taper method (MTM) spectra and wavelet analysis showed that the reconstructed PDSI series had high and low frequency periods (2.4–3.3 and 85–92 years). Our findings provide an understanding of the drought history of the semiarid forest-steppe ecotone of western Mongolia.

Algorithm of reconstruction of a three-dimensional crystal structure from two-dimensional projections

The article deals with a problem of three-dimensional crystal lattice reconstruction, which is an important stage in the X-ray structural analysis. The accuracy of parametric and structural identification of crystals directly depends on the quality of crystal lattice reconstruction. The proposed algorithm of reconstruction of a three-dimensional crystal lattice is based on minimizing the distances from each node to a line projected onto a specified plane. Three sets of two-dimensional node coordinates, obtained from three two-dimensional projections, are used as input data. We performed an analytical calculation of the reconstruction error, allowing the total reconstruction accuracy to be estimated. The results of computational experiments confirmed the high quality of the proposed reconstruction algorithms and its stability against the distortion of node coordinates. In addition, we revealed a problem of lattice system separability, with the identification accuracy for monoclinic, rhombic and tetragonal systems found to be 34%, 53% and 10%, respectively.

Management of cavernous abdominal wall defects post radical cystectomy in adult exstrophy complex

The exstrophy–epispadias complex represents a spectrum of genitourinary malformations ranging from simple glanular epispadias to an overwhelming multisystem defect, cloacal exstrophy. Neonatal total reconstruction of bladder exstrophy–epispadias complex is the treatment of choice. An adult patient presenting with untreated exstrophy is very rare. Malignant transformation, commonly adenocarcinoma, in such cases is a known complication due to mucosal metaplasia of urothelium. Management in such cases necessitates a radical surgical procedure that often results in a massive defect in the anterior abdominal wall. Providing a cover for such defects is a challenging task for the reconstructive surgeon. Local skin flaps and wide mobilisation of the rectus muscle are the usually employed techniques for closure of such defects. However, these may be inadequate in extremely large defects such as those encountered in our patients. We, hereby, describe our technique of closure of the abdominal wall defect using a pedicled anterolateral thigh flap.

Locating Nowhere

This chapter examines the proliferation of utopian literature in the United States and Great Britain during the late nineteenth century, mainly due to the economic and social upheavals resulting from industrial capitalism. In particular, it shows how writers such as Edward Bellamy and Thomas More came up with their visions of peaceful and egalitarian future worlds in response to the turbulence of their era. The chapter first provides an overview of the Great Depression experienced by both the United States and Great Britain between 1873 and 1896, a period characterized by extreme poverty and unemployment, before discussing the history of More's Utopia (1516). It then considers how utopian socialists in Europe and the United States, including Henri de Saint-Simon, Robert Owen, and Charles Fourier, devised schemes for the total reconstruction of society. It also analyzes Henry George's utopian vision, which he articulated in his 1879 book Progress and Poverty.

Efficient Computerized-Tomography Reconstruction Using Low-Cost FPGA-DSP Chip

In this paper, filtered back-projection algorithm is optimally implemented using low-cost Spartan 3A-DSP 3400 chip. The optimization enables parallel implementation. The combination of the pixel parallelism and projection parallelism is presented to significantly reduce the total reconstruction time to produce the image. The applied data is presented in fixed point format to achieve efficient implementation with maximum speed. The selection of data bus-width is optimized with very little error and good visual quality required for medical images. Before implementation, the computer tomography ( CT ) reconstruction simulator is developed to provide a testing reference for the hardware implementation. Using the combination of the pixel parallelism and projection parallelism, the presented hardware design achieves image reconstruction of a 512-by-512 pixel image from 1024 projections in 134. 8ms using 50 MHz clock cycles. It achieves the reduction of the required number of clock cycles to form an image from projections by 60 % comparing to the state of the art of the reconstruction time using field programmable gate array ( FPGA ) design.