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Reggio Calabria, Italy

Muscolino G.,Building Information | Santoro R.,Building Information | Sofi A.,Energy
Safety, Reliability, Risk and Life-Cycle Performance of Structures and Infrastructures - Proceedings of the 11th International Conference on Structural Safety and Reliability, ICOSSAR 2013

The present study deals with the interval sensitivity analysis of linear discretized structures with uncertain-but-bounded parameters subjected to stationary multi-correlated Gaussian stochastic processes. The proposed procedure allows to derive approximate explicit expressions of the interval sensitivities of the meanvalue vector and Power Spectral Density (PSD) matrix of the interval stationary stochastic response. The core of the procedure is the so-called Interval Rational Series Expansion (IRSE), recently proposed by the authors as an alternative explicit expression of the Neumann series expansion for the inverse of a matrix with a rank-r modification and properly extended to handle also interval matrices. Numerical results pertaining to a truss structure with intervalYoung's moduli are presented to demonstrate the effectiveness of the proposed method as well as to show the great value of interval sensitivity analysis for design purposes. © 2013 Taylor & Francis Group, London. Source

Hanspal N.S.,Energy | Nassehi V.,Loughborough University | Kulkarni A.,Tech Hampshire
International Journal for Numerical Methods in Fluids

Conjunctive modelling of free/porous flows provides a powerful and cost-effective tool for designing industrial filters used in the process industry and also for quantifying surface-subsurface flow interactions, which play a significant role in urban flooding mechanisms resulting from sea-level rise and climate changes. A number of well-established schemes are available in the literature for simulation of such regimes; however, three-dimensional (3D) modelling of such flow systems still presents numerical and practical challenges. This paper presents the development of a fully 3D, transient finite element model for the prediction and quantitative analyses of the hydrodynamic behaviour encountered in industrial filtrations and environmental flows represented by coupled flows. The weak-variational formulation in this model is based on the use of C0 continuous equal-order Lagrange polynomial functions for velocity and pressure fields represented by 3D hexahedral finite elements. A mixed UVWP finite element scheme based on the standard Galerkin technique satisfying the Ladyzhenskaya-Babuska-Brezzi stability criterion through incorporation of an artificial compressibility term in the continuity equation has been employed for the solution of coupled partial differential equations. We prove that the discretization generates unified stabilization for both the Navier-Stokes and Darcy equations and preserves the geometrical flexibility of the computational grids. A direct node-linking procedure involving the rearrangement of the global stiffness matrix for the interface elements has been developed by the authors, which is utilized to couple the governing equations in a single model. A variety of numerical tests are conducted, indicating that the model is capable of yielding theoretically expected and accurate results for free, porous and coupled free/porous problems encountered in industrial and environmental engineering problems representing complex filtration (dead-end and cross-flow) and interacting surface-subsurface flows. The model is computationally cost-effective, robust, reliable and easily implementable for practical design of filtration equipments, investigation of land use for water resource availability and assessment of the impacts of climatic variations on environmental catastrophes (i.e. coastal and urban floods). The model developed in this work results from the extension of a multi-disciplinary project (AEROFIL) primarily sponsored by the European aerospace industries for development of a computer simulation package (Aircraft Cartridge Filter Analysis Modelling Program), which was successfully utilized and deployed for designing hydraulic dead-end filters used in Airbus A380. © 2012 John Wiley & Sons, Ltd. Source

Padden L.K.,Padden Engineering LLC | Lockley B.,Lockley Engineering | Mistry B.,Energy | Wood B.,Chevron
IEEE Transactions on Industry Applications

This paper presents an overview of IEEE 1349-2011, a guide that assists individuals, organizations, and suppliers with the application of motors in Class I, Division 2 and Class I, Zone 2 locations, where flammable gases and vapors may occasionally be present. AC synchronous and induction motors in ratings of 0.18 kW (1/4 hp) and larger are covered. Primary emphasis is on the use of open or nonexplosionproof or nonflameproof enclosed motors in Class I, Division 2 and Class I, Zone 2 locations as covered in NFPA 70-2011. Precautions against excessive surface temperatures and sparking are included. To mitigate hot surface temperatures and sparking, this document provides guidance for selecting, operating, and maintaining motors. IEEE 1349-2001 included Class I, Division 2 applications, and IEEE 1349-2011 was expanded to cover Class I, Zone 2 applications. The new release updates guidance, adds new motor temperature test data submitted by manufacturers and users, expands adjustable speed drive (ASD) application information including a Common ASD section and common-mode voltage calculation method, details additional test methods for determining motor rotor temperature (nondestructive), and includes documented events since 2001. Manufacturers, users, and other industry experts worked about six years to update this consensus standard. This paper does not replace the guide but should be used to supplement and understand the guide, providing examples and highlighting new information. © 2012 IEEE. Source

Diaz-Chavez R.,Imperial College London | Berndes G.,Chalmers University of Technology | Neary D.,Rocky Research | Fall M.,Energy
Biofuels, Bioproducts and Biorefining

Water quality is a measurement of the biological, chemical, and physical characteristics of water against certain standards set to ensure ecological and/or human health. Biomass production and conversion to fuels and electricity can impact water quality in lakes, rivers, and aquifers with consequences for aquatic ecosystem health and also human water uses. Depending on how the bioenergy system is located and managed, it can lead to both water quality deterioration and to improvements. This review focuses on the effects of bioenergy on water quality, on ways to quantify these effects, and on options for reducing negative impacts. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd Copyright © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd. Source

Johansson J.E.,Energy
JPT, Journal of Petroleum Technology

The Economist Intelligence Unit surveyed more than 500 European and US executives in July and August 2009 as part of Celerant Consulting's second annual global survey on change, to assess the impact of economic crisis on firms. More than half of global business executives responded that the current economic crisis has revealed shortcomings in their organization. The survey revealed that only 6% of firms have suspended change programs and structured approaches to implementing and managing change within a company as a result of the financial crisis. The firms aimed towards cost cutting are addressing a broad range of integrated processes to establish and improve their ability to serve customers at lower costs. More than two-thirds of respondents say that their companies are dealing with the changes resulting from the financial and economic crisis reasonably well. Source

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