Search results for " flows"
showing 10 items of 110 documents
Discussion of "preliminary Study of Surface Hydraulic Jumps" by S. Ahmed, Y. Ye, H. Liu, and N. Rajaratnam
2020
In this paper the results of Preliminary Study of Surface Hydraulic Jumps” by S. Ahmed, Y. Ye, H. Liu, and N. Rajaratnam are discussed
Hyper-concentrated flow and surface velocity estimation by digital imaging technique: a study case
2015
This paper investigates the utility of digital imaging technique for performing surface velocity measurements of hyper-concentrated flows. The analysis is conducted with the aid of data collected in a scale laboratory flume constructed at the Hydraulic laboratory of the Department of Civil, Environmental, Aerospatial and of Materials Engineering (DICAM) – University of Palermo (Italy). In particular the present paper describes the setup of a laboratory test and the applicability of a fully digital imaging approach.
Risk Management Optimization for Sovereign Debt Restructuring
2015
Abstract Debt restructuring is one of the policy tools available for resolving sovereign debt crises and, while unorthodox, it is not uncommon. We propose a scenario analysis for debt sustainability and integrate it with scenario optimization for risk management in restructuring sovereign debt. The scenario dynamics of debt-to-GDP ratio are used to define a tail risk measure, termed conditional Debt-at-Risk. A multi-period stochastic programming model minimizes the expected cost of debt financing subject to risk limits. It provides an operational model to handle significant aspects of debt restructuring: it collects all debt issues in a common framework, and can include contingent claims, m…
El sistema regional andaluz de los servicios avanzados (SA) con los distintos sectores económicos
2002
El artículo estudia la caracterización del entorno productivo de los SA a través de la creación de espacio relacional. El objetivo es medir su nivel tecnológico, el del espacio productivo andaluz y conocer en qué fase de la sociedad servindustrial se encuentra. Las empresas de gestión de calidad y de consultoría son las que concentran el mayor número de servicios comprados frente a los Organismos Públicos de Investigación (OPIs) que suministran el grueso de la I+D a los sectores económicos. Gran parte de la contratación de los SA y de la cooperación se realiza a escala regional, pero la densidad de relaciones es baja y poco contínua. Se trata de un sistema regional fragmentado. This paper s…
Solid sediment transport in turbulent channel flow over irregular rough boundaries
2017
Abstract The presence of a loading of dispersed particles in a turbulent flow affects the dynamics of the carrier flow field which, in turn, drives grains movement. The focus of the paper is on the analysis of the coupling effects between near-bed turbulence structures and the dynamics of dispersed suspended solid particles in wall-bounded turbulent multiphase flows. We consider turbulent horizontal channel flows bounded by rough boundaries. The friction Reynolds number of the unladen flow is R e τ = 180 and the dispersed phase spans one order of magnitude of particle diameter. To analyze sedimentation and suspended phase transport, we adopt concepts and modeling ideas derived from the Eule…
A Chain of Words as an Introduction: Human Dignity, Language, Identity, Citizenship, Values, Human Capital and Urban Spaces
2022
To analyze the issue of cities-migrants interactions, as well as social-monetary values interactions, it is necessary to place it in a “higher” context, in order not to risk losing the necessary connection with universal ethical principles, and in a “broader” one, in which understanding complexity on a global scale interprets local conditions. The study of migration flows and urban dynamics, as well as housing markets, through theoretical paradigms and scientific tools from different disciplines provides an opportunity to learn and compare, dialogue and interface with new keys to understanding the problem, or with alternative interpretations and unprecedented perspectives in the path of mul…
Local gas-liquid hold-up and interfacial area via light sheet and image analysis
2010
Particle Image Velocimetry techniques coupled with advanced Image Processing tools are receiving an increasing interest for measuring flow quantities and local bubble-size distributions in gas-liquid contactors. In this work, an effective experimental technique for measuring local gas hold-up and interfacial area, as well as bubble size distribution, is discussed. The technique, hereafter referred to as Laser Induced Fluorescence with Shadow Analysis for Bubble Sizing (LIF-SABS) is based on laser sheet illumination of the gas-liquid dispersion and synchronized camera, i.e. on equipment typically available within PIV set-ups. The liquid phase is made fluorescent by a suitable dye, and an opt…
A decoupled method for solving distribution networks with PV nodes
2009
In this paper, a methodology for the load flow solution of distribution systems with fixed voltage nodes (PV nodes) is presented. The proposed technique is the extension of a methodology already set up by the authors to solve distribution systems; it is an iterative approach devoted to the treatment of voltage dependent loads; at each iteration, all the network components (lines, loads, and PV nodes) are represented by resistances and reactances. The methodology is based on the identification of two networks that are solved in sequence, thus allowing the attainment of state features of the original system. One of the two systems is made up only of shunt and series resistances; the other onl…
Conclusioni
2012
La macroecomia della finanza ha ridotto i vincoli di libertà delle nazioni in assenza di una codificazione delle regole condivise da tutti i partecipanti al sistema economico internazionale. La dimensione spaziale della crescita, invece, è probabilmente una risposta adatta ai processi di cambiamento in atto e complementare alle risposte fino ad oggi fornite. La marginalità per lo sviluppo regionale, ovvero l’ampia utilizzazione di giacimenti economici, individuali, innovativi poco esplorati, assume un valore strategico perché rivaluta, nell’ambito dei processi di cambiamento economico, l’importanza dei contesti regionali e locali nei loro diversi ambiti. sfida e una scelta per il cambiament…
Isotropic stochastic flow of homeomorphisms on Sd for the critical Sobolev exponent
2006
Abstract In this work, we shall deal with the critical Sobolev isotropic Brownian flows on the sphere S d . Based on previous works by O. Raimond and LeJan and Raimond (see [O. Raimond, Ann. Inst. H. Poincare 35 (1999) 313–354] and [Y. LeJan, O. Raimond, Ann. of Prob. 30 (2002) 826–873], we prove that the associated flows are flows of homeomorphisms.