Time-Dependent Z-R Relationships for Estimating Rainfall Fields from Radar Measurements

Abstract. The operational use of weather radars has become a widespread and useful tool for estimating rainfall fields. The radar-gauge adjustment is a commonly adopted technique which allows one to reduce bias and dispersion between radar rainfall estimates and the corresponding ground measurements provided by rain gauges. This paper investigates a new methodology for estimating radar-based rainfall fields by recalibrating at each time step the reflectivity-rainfall rate (Z-R) relationship on the basis of ground measurements provided by a rain gauge network. The power-law equation for converting reflectivity measurements into rainfall rates is readjusted at each time step, by calibrating its parameters using hourly Z-R pairs collected in the proximity of the considered time step. Calibration windows with duration between 1 and 24 h are used for estimating the parameters of the Z-R relationship. A case study pertaining to 19 rainfall events occurred in the north-western Italy is considered, in an area located within 25 km from the radar site, with available measurements of rainfall rate at the ground and radar reflectivity aloft. Results obtained with the proposed method are compared to those of three other literature methods. Applications are described for a posteriori evaluation of rainfall fields and for real-time estimation. Results suggest that the use of a calibration window of 2–5 h yields the best performances, with improvements that reach the 28% of the standard error obtained by using the most accurate fixed (climatological) Z-R relationship

Investigation on edge joints of Inconel 625 sheets processed with laser welding

Abstract Laser welding of Inconel 625 edge joint beads in square groove configuration was investigated. The use of different weld geometries in new aerospace solutions explains research on edge joints. A structured plan was carried out in order to characterize the process defining the influence of laser power and welding speed and to study possible interactions among the governing factors. As weld pool protection is crucial in order to obtain sound joints when processing superalloys, a special glove box for gas supply was designed to upgrade the welding head. Welded joints were characterized referring to bead profile, microstructure and X-rays. It was found that heat input plays an important role as it affects welding stability, porosity content and bead shape. Results suggest operating with low values of heat input to reduce porosity and guarantee stable bead conformation. Furthermore, a decrease in the grain size has been observed as a consequence of decreasing heat input

Forme e usi della memoria nel corpus gesuitico del XVII secolo. Fra istruzione, spiritualità, missione

The essay investigates uses and meanings of memory in a selection of texts produced by members of the Society of Jesus in the 17th century active in the territories of the Spanish Monarchy. In the first part, it examines the significance of this category in the apparatus of norms regulating daily life and especially the activity characterising the order, namely teaching. Memory is a practical faculty predisposing the individual to future action, and plays a key role in both pedagogy and in the discipline of teachers. Mission and confession, other operational cores of the order, are examined in the second part. The accounts of the Fathers produced while travelling through the territories of the Iberian Peninsula document those places and encounters, but above all the mentality of those who produced them

Sacrificio del desiderio e matrimonio cristiano fra tardomedioevo e prima età moderna

The essay examines the positions of Catholic doctrine in the early modern age on the connection between sacrifice and sexuality. It was examined a body of moral literature characterised by different levels of specialisation and relative recipients: manuals of spiritual instruction aimed at educated readers but not necessarily members of the clergy, texts for confessors and judges settling matrimonial disputes, works of wide circulation and others that remained in the shadows. A common line emerges: the sacrificial condition is desirable and necessary, and the conjugal status is hopelessly second to that, far more noble, far more sacrificial, of the religious devoted to celibacy

Un réseau miraculaire. Relations, acteurs et significations de la douleur autour des guérisons du jésuite Giuseppe Pignatelli (première moitié du xixe siècle)

Cet article examine une série de guérisons prétendument miraculeuses attri- buées à l’intercession du jésuite aragonais Giuseppe Pignatelli (1737-1811). La recherche prend sa source dans le dossier conservé au sein du fonds de la Postulation générale des Archives de la Curie générale des jésuites à Rome, qui contient les documents recueillis par ses promoteurs en vue de l’introduction de la cause apostolique. Ceux-ci sont lus par croisement avec les dossiers des procès ouverts entre Rome, Milan, Bologne et Parme, et avec d’autres types de sources issus de différents acteurs impliqués dans les lieux où se produisent les prétendues guérisons (rapports médicaux, correspondances, journaux). Dans cette enquête sur les tensions et les sujets impliqués dans la promotion de la sainteté de Pignatelli, icône de la transition entre l’Ancienne et la Nouvelle Compagnie de Jésus, un réseau de relations émerge au centre duquel le corps féminin souffrant joue un rôle crucial

Column generation for minimizing total completion time in a parallel-batching environment

This paper deals with the 1 | p- batch , sj≤ b| ∑ Cj scheduling problem, where jobs are scheduled in batches on a single machine in order to minimize the total completion time. A size is given for each job, such that the total size of each batch cannot exceed a fixed capacity b. A graph-based model is proposed for computing a very effective lower bound based on linear programming; the model, with an exponential number of variables, is solved by column generation and embedded into both a heuristic price and branch algorithm and an exact branch and price algorithm. The same model is able to handle parallel-machine problems like Pm| p- batch , sj≤ b| ∑ Cj very efficiently. Computational results show that the new lower bound strongly dominates the bounds currently available in the literature, and the proposed heuristic algorithm is able to achieve high-quality solutions on large problems in a reasonable computation time. For the single-machine case, the exact branch and price algorithm is able to solve all the tested instances with 30 jobs and a good amount of 40-job examples

Understanding stochastic perturbation theory: toy models and statistical analysis

The numerical stochastic perturbation method based on Parisi-Wu quantisationis applied to a suite of simple models to test its validity at high orders.Large deviations from normal distribution for the basic estimators aresystematically found in all cases (``Pepe effect''). As a consequence oneshould be very careful in estimating statistical errors. We present someresults obtained on Weingarten's ``pathological'' model where reliable resultscan be obtained by an application of the bootstrap method. We also present someevidence that in the far less trivial application to Lattice Gauge Theory asimilar problem should not arise at moderately high loops (up toO(\alpha^{10}))

Novel strategies for the characterization of cancellous bone morphology: Virtual isolation and analysis

Objectives: The advent of micro-computed tomography (μCT) made cancellous bone more accessible than ever before. Nevertheless, the characterization of cancellous bone is made difficult by its inherent complexity and the difficulties in defining homology across datasets. Here we propose novel virtual methodological approaches to overcome those issues and complement existing methods. Materials and methods: We present a protocol for the isolation of the whole cancellous region within a μCT scanned bone. This method overcomes the subsampling issues and allows studying cancellous bone as a single unit. We test the protocol on a set of primate bones. In addition, we describe a set of morphological indices calculated on the topological skeleton of the cancellous bone: node density, node connectivity, trabecular angle, trabecular tortuosity, and fractal dimension. The usage of the indices is shown on a small comparative sample of primate femoral heads. Results: The isolation protocol proves reliable in isolating cancellous structures from several different bones, regardless of their shape. The indices seem to detect some functional differences, although further testing on comparative samples is needed to clarify their potential for the study of cancellous architecture. Conclusions: The approaches presented overcome some of the difficulties of trabecular bone studies. The methods presented here represent an alternative or supporting method to the existing tools available to address the biomechanics of cancellous bone

Structure of a nucleosome-bound MuvB transcription factor complex reveals DNA remodelling.

Genes encoding the core cell cycle machinery are transcriptionally regulated by the MuvB family of protein complexes in a cell cycle-specific manner. Complexes of MuvB with the transcription factors B-MYB and FOXM1 activate mitotic genes during cell proliferation. The mechanisms of transcriptional regulation by these complexes are still poorly characterised. Here, we combine biochemical analysis and in vitro reconstitution, with structural analysis by cryo-electron microscopy and cross-linking mass spectrometry, to functionally examine these complexes. We find that the MuvB:B-MYB complex binds and remodels nucleosomes, thereby exposing nucleosomal DNA. This remodelling activity is supported by B-MYB which directly binds the remodelled DNA. Given the remodelling activity on the nucleosome, we propose that the MuvB:B-MYB complex functions as a pioneer transcription factor complex. In this work, we rationalise prior biochemical and cellular studies and provide a molecular framework of interactions on a protein complex that is key for cell cycle regulation

redesign and manufacturing of a metal towing hook via laser additive manufacturing with powder bed

Abstract An approach to redesign and manufacture a metal towing hook via Selective Laser Melting is discussed. Some reference criteria and general guidelines are considered step-by-step to concurrently address lightening, manufacturability and job planning. Grounds are given for the application of Additive Manufacturing for complex components to the purpose of material saving and increased safety factor