1,721,127 research outputs found
Direzione e forme organizzative dell'internazionalizzazione delle banche italiane: un'analisi panel
No full textDirezione e forme organizzative dell'internazionalizzazione delle banche italiane: un'analisi panel
No full textAn overview of the geological and morphological constraints in the excavation of artificial cavities
No full textThe habit of man to excavate artificial cavities began a very long time ago. Man’s efforts were initially moved by the need
to have a safe place to live, to control the surrounding territory, to collect and transport water, to exploit the natural
resources. For all these purposes, he had to face a number of geological and morphological constraints that, depending on
site characteristics, guided, favored or complicated the excavation. Therefore, all the phases in the “life” of an artificial
cavity, from the original idea, to planning and realization, up to its later evolution and possible conservation, depend in
some ways on geology and morphology. Lithology of hosting rock is the first aspect to consider: the rock mass must allow
hand excavation but, at the same time, it should present physical-mechanical characteristics such to support the newlyformed
cavity. The geological and structural setting, including the main faults and the discontinuity systems in the rock
mass, have to be particularly taken into account. Choice of the site where to locate an artificial cavity is also dictated by
morphology, the morphological factors being, in turn, strictly related to land management and control. When safety reasons
were considered to be the main priority, for instance, those sites that apparently were extremely difficult to excavate and
to settle in were chosen. Morphology is also strictly related to slope instability. Several rock settlements situated at the
borders of deep valleys and ravines are directly involved in mass movements, due to natural evolution of the slopes and
to open cracks produced by the tensional release in the unsupported rock mass. Inside the artificial cavities, in turn,
problems of instability may be observed. Locally, these may become so significant to compromise the overall stability of
the structure. Slope instability processes deserve a greater attention from cavers and scientists, since their effects might be
extremely dangerous for people visiting and working in artificial cavities, and for the cultural heritage therein contained
as well. Availability of water resources is a further factor that controlled during historical times the choice of sites for
settlements and towns. As a consequence, the hydrogeology plays a crucial role for artificial cavities, and particularly for
those works intended to collect and transport water to settlers and inhabitants. Aqueducts, tunnels, fountains are, for the
reasons above, very important to study in the context of the geological and hydrogeological setting, considering at the
same time the social and historical aspects of the community that designed and realized them. The present contribution is
an attempt in categorizing the aforementioned factors that play a role in the realization of artificial cavities. The topic is
very wide, covering several interrelated disciplines and field of research, and should deserve to be treated with much
greater detail and thoroughness. Our goal is therefore to stimulate with this article cavers and interested scientists in
carrying out studies about the crucial role that geology and morphology have in the development of artificial cavitie
L’influenza dei fenomeni franosi sugli insediamenti costieri del distretto flegreo (Campania, Italia)
No full textA Study on Secret Key Rate in Wideband Rice Channel
Full text linkStandard cryptography is expected to poorly fit IoT applications and services, as IoT devices can hardly cope with the computational complexity often required to run encryption algorithms. In this framework, physical layer security is often claimed as an effective solution to enforce secrecy in IoT systems. It relies on wireless channel characteristics to provide a mechanism for secure communications, with or even without cryptography. Among the different possibilities, an interesting solution aims at exploiting the random-like nature of the wireless channel to let the legitimate users agree on a secret key, simultaneously limiting the eavesdropping threat thanks to the spatial decorrelation properties of the wireless channel. The actual reliability of the channel-based key generation process depends on several parameters, as the actual correlation between the channel samples gathered by the users and the noise always affecting the wireless communications. The sensitivity of the key generation process can be expressed by the secrecy key rate, which represents the maximum number of secret bits that can be achieved from each channel observation. In this work, the secrecy key rate value is computed by means of simulations carried out under different working conditions in order to investigate the impact of major channel parameters on the SKR values. In contrast to previous works, the secrecy key rate is computed under a line-of-sight wireless channel and considering different correlation levels between the legitimate users and the eavesdropper
Sinkhole in contesti carbonatici di aree di catena e di avampaese: confronto tra l'Appennino campano e l'avampaese apulo.
No full textNew data on the piping sinkholes formation: the case study of the forino plain (Campania, southern Italy).
No full textNuove ipotesi sulla formazione dei piping sinkhole in aree alluvionali: il caso della piana di Forino (AV- Campania).
No full textOrogin and distribuition of different types of sinkholes in the plain areas of southern Italy
No full textTwo faces for Janus: recombinant human erythropoiesis-stimulating agents and cancer mortality.
No full textUntreated anemia in cancer patients has severe consequences for many organ systems. Erythropoiesis-stimulating agents (ESAs) are indicated for the treatment of chemotherapy-induced anemia in cancer patients. Several studies in patients with solid tumors have shown that these agents effectively increase hemoglobin levels, improve the quality of life and reduce the requirement for emergency blood transfusions, regardless of the type of concomitantly administered chemotherapy. The meta-analysis evaluates the impact of ESAs during the active study period on mortality and the overall survival during the longest available follow-up, irrespective of anticancer treatment, with little heterogeneity between trials. A total of 10,441 patients on chemotherapy were enrolled in 38 trials. There was little evidence for a difference between trials of patients administered different anticancer treatments (p for interaction = 0.42). The meta-analysis demonstrated that ESAs increased mortality by 17% during the active study periods and worsened overall survival in patients with cancer. However, 62% of patients evaluated in this analysis started the ESA therapy with basal hemoglobin values over that recommended by ASCO/ASH guidelines. However, the high quality of meta-analysis and the novelty of the information do not represent an obstacle for the continued the use of ESAs within the revised European Organisation for Research and Treatment of Cancer (EORTC) guidelines and the revised labels
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