Search results for "PROCESSES"

F-contractions of Hardy–Rogers-type and application to multistage decision

2016

We prove fixed point theorems for F-contractions of Hardy–Rogers type involving self-mappings defined on metric spaces and ordered metric spaces. An example and an application to multistage decision processes are given to show the usability of the obtained theorems.

Permutation invariant functionals of Lévy processes

2017

Stability of melt flow during magnetic sonication in a floating zone configuration

2018

Combined static and alternating magnetic fields are shown to create an oscillating pressure that can cause cavitation in molten metals. A time-averaged flow is also excited, consisting of two tori squeezed to thin boundary layers. Flow instability develops as a standing wave between these tori.

Optical study for springback prediction, thickness reduction and forces variations on single point incremental forming

2019

Abstract The goal of the present work is to present an experimental study regarding the influence of the main technological influence factors such as the vertical step and the punch diameter on the single point incremental forming process (SPIF). In this paper we estimate the influence of these two factors on springback, thickness reduction and forces. Both parameters were varied on two levels: (d) punch diameter 6 and 10 mm and (s) vertical step 0,1 and 0,5 mm. The experiments were done on experimental layout composed by a robot, a clamping system that contains the die’s lower part and the optical system.

Surface sediment dynamics along the shore of Hammamet Gulf (Tunisia, southern Mediterranean)

2016

International audience; In the summer of 2015 the authors analysed grain size and surface sediment composition through high spatial resolution from samples taken at 53 stations along the Hammamet coast (southern Mediterranean Sea). The Acoustic Doppler Current Profiler deployed in this study showed that the surface current flows toward the north-east, parallel to the coast at a maximum speed along the main axis of about 5.9 cm s−1. Near the bottom the current flows toward the north-west at a maximum speed of 2.2 cm s−1. The tide plays a relatively small role in water circulation in Hammamet Gulf. Spatial distribution of particle size, along with speed and current direction analysis, furnish…

Annually resolved δ13Cshell chronologies of long-lived bivalve mollusks (Arctica islandica) reveal oceanic carbon dynamics in the temperate North Atl…

2011

Abstract The ability of the ocean to absorb carbon dioxide is likely to be adversely affected by recent climate change. However, relatively little is known about the spatiotemporal variability in the oceanic carbon cycle due to the lack of long-term, high-resolution dissolved inorganic carbon isotope ( δ 13 C DIC ) data, especially for the temperate North Atlantic, which is the major oceanic sink for anthropogenic CO 2 . Here, we report shell carbon isotope values ( δ 13 C shell ), a potential proxy for δ 13 C DIC , of old-grown specimens of the long-lived bivalve mollusk, Arctica islandica . This paper presents the first absolutely dated, annually resolved δ 13 C shell record from surface …

Modeling Rain Isotopic Composition under Orographic Control: A Landscape Approach for Hydrogeological Applications

2021

Oxygen isotopic composition is useful for individuating recharge areas of groundwater bodies by the comparison with those of local rainfalls. While on a global scale general relationships, such as the isotopic vertical gradient or continentality effects, efficiently describe spatial variations of the isotopic signature, hydrogeological applications need spatial models that are more focused on the effects of local topographic structures and/or subsoil geology. This work presents a case study in northeastern Sicily (Italy) characterized by complex geological and orographic structures, in which isotopic composition of rainfalls is governed by orographic effects and the varying initial composit…

Dimensionless Stage-Discharge Relationship for a Non-Linear Water Reservoir: Theory and Experiments

2020

In the field of hydrology, stage&ndash

Measuring rill erosion using structure from motion: A plot experiment

2017

Abstract In this paper the results of a plot experiment on rill erosion are reported. The rill network, manually incised on the soil and further shaped by a clear inflow discharge, was surveyed using the three-dimensional photo-reconstruction (3D-PR) technique which allows to obtain a digital terrain model (DTM) by a large series of oblique images of the channel from consumer un-calibrated and non-metric cameras. The three-dimensional (3D) DTM and the quasi-tridimensional (2.5D) model were generated by Agisoft Photoscan software. For a single rill channel, the reliability of the 3D image-based ground measurements of morphological and hydraulic variables was positively tested by the correspo…

Using scintillometry to assess reference evapotranspiration methods and their impact on the water balance of olive groves

2016

Abstract Reference evapotranspiration (ET 0 ) is widely used for irrigation scheduling, to promote an efficient use of water resources for a sustainable agro-ecosystem productivity, as well as to manage water quality and to face other environmental concerns. As suggested by ASCE-EWRI and FAO, standard Penman–Monteith methods are generally applied for an accurate estimation of ET 0 from hourly to daily scale. In absence of detailed meteorological information several simplified equations, using a limited number of variables, have been proposed as alternative. In this paper, the performance of different reference evapotranspiration methods, at hourly (Penman–Monteith, Pristley–Taylor, Makkink …