Effective stiffness behaviour of sandwich beams under uncoupled bending and torsion loadings

Sandwich geometries, mainly in the form of panels and beams, are commonly applied in various transportation industries, such as aerospace, aeronautic and automotive. Sandwich geometries represent important advantages in structural applications, namely high specific stiffness, low weight, and possibility of design optimization prior to manufacturing. The aim of this paper is to uncover the influence of the number of reinforcements (ribs), and of the thickness on the mechanical behavior of all-metal sandwich panels subjected to uncoupled bending and torsion loadings. In this study, four geometries are compared. The orientation of the reinforcements and the effect of transversal ribs are also considered in this study. It is shown that the all the relations are non-linear, despite the elastic nature of the analysis in the Finite Element software ANSYS MECHANICAL APDL.

“Safety and health” as a criterion in the choice of tunneling method

Risk management is of paramount importance in the success of tunnelling works and is linked to the tunnelling method and to the constraints of the works. Sequencial Excavation Method (SEM) and Tun-nel Boring Machine (TBM) method have been competing for years. This article, part of a wider study on the influence of the â Safety and Healthâ criterion in the choice of method, reviews the existing literature about the criteria usually employed to choose the tunnelling method and on the criterion â Safety and Healthâ . This crite-rion is particularly important, due to the financial impacts of work accidents and occupational diseases. This article is especially useful to the scientific and technical community, since it synthesizes the relevance of each one of the choice criteria used and it shows why â Safety and Healthâ must be a criterion in the decision mak-ing process to choose the tunnelling method.

O processo de legitimação e a gestão de impressões na comunicação organizacional: O caso da EDP – Energias de Portugal, S.A.

Tese de Doutoramento Ciências Empresariais

Experimental and model-based analysis of the steady-state and dynamic operating behaviour of the direct methanol fuel cell (DMFC)

Direct methanol fuel cell, DMFC, model, mass transport, Maxwell-Stefan, Flory-Huggins, crossover, polymer electrolyte membrane, Nafion

Financial structure choice in owner-managed firms : entrepreneurial characteristics, utility of control, and the competitive context

Magdeburg, Univ., Fak. für Wirtschaftswiss., Diss., 2011

System-oriented analysis of the dynamic behaviour of direct methanol fuel cells

DMFC, dynamic behaviour, current steps, system analysis, methanol oxidation, flow field design

Influence of pore size distribution on drying behaviour of porous media by a continuous model

Bundle of capillaries, drying kinetics, continuous model, relative permeability, capillary pressure, control volume method

Modelling the influence of microstructure on elastic properties and tensile damage behaviour of Mo-base silicide alloys

Mo-Si-B alloys, Real microstructures, Voronoi structures, Microstructural characterization, Modelling and finite element simulations, Effective material properties, Damage and Crack growth, tensile strength, fracture toughness

Simulation of the deformation behaviour of two-phase composites

Two-phase polycrystal, elasto-viscoplastic material model, heterogeneity, anisotropy, flow behaviour, crystallographic texture, strain field

Numerical investigation of micro and macro mechanical behaviour of granular media via a discrete element approach

Magdeburg, Univ., Fak. für Mathematik, Diss., 2009

Impact of casting parameters and chemical composition on the solidification behaviour of Al-Si-Cu hypoeutectic alloy

Magdeburg, Univ., Fak. für Maschinenbau, Diss., 2010

Existence, multiplicity and behaviour of solutions of some elliptic differential equations of higher order

Magdeburg, Univ., Fak. für Mathematik, Diss., 2009

Targeted search engines for children : search user interfaces and information-seeking behaviour

Magdeburg, Univ., Fak. für Informatik, Diss., 2015

Bestimmung von Präferenzen bei der Studiengangs- und Studienortwahl aus Sicht von Studierenden mittels Choice-Based Conjointanalyse

Diese Bachelorarbeit gliedert sich in einen theoretischen und einen praktischen Abschnitt. Zunächst werden Studien- und Berufswahlmodelle aus theoretischer Sicht betrachtet. Dabei ist festzuhalten, dass kein Ansatz existiert, der den komplexen Studienwahlprozess vollständig abbildet und erklärt. Jedoch ergänzen sich verschiedene Modelle, sodass alle bedeutenden Einflussfaktoren berücksichtigt sind. Ebenso die Conjointanalyse wird einer theoretischen Betrachtung unterzogen. Als eine Methode der Präferenzmessung wird dieses Analyseverfahren häufig eingesetzt, um die Vorziehenswürdigkeit von Produkten zu ermitteln. Sowohl im Bereich der Neuproduktentwicklung, als auch bei der Marktsegmentierung und der Preisfindung findet die Analyse Verwendung. Sehr charakteristisch für die Methodik ist, dass die Präferenzbeurteilung ganzheitlich für das Produkt erfolgt und nicht direkt einzelne Produkteigenschaften bei der Auskunftsperson abgefragt werden. Besonders relevant für diese Arbeit ist die Choice-Based Conjointanalyse. Die Vorziehenswürdigkeit von Konzepten werden basierend auf Auswahlentscheidungen von Probanden erfasst. Die Beweggründe bei der Studienortwahl aus Sicht der Studierenden an der Hochschule Anhalt werden im praktischen Abschnitt dieser Ausarbeitung mit Hilfe der Choice-Based Conjointanalyse untersucht. Dafür wurde ein Fragebogen entwickelt. Es konnte ermittelt werden, dass sowohl der Ruf der Hochschule, als auch die Heimatnähe und die Höhe des Semesterbeitrages bedeutende Einflussfaktoren bei der Studiengangwahl darstellen. Darüber hinaus werden Motive der Studiengangwahl analysiert. Festzuhalten ist, dass sowohl intrinsische Motive, aber auch extrinsische Motive von hoher Wichtigkeit sind.

The Barcelonnettes: an example of network-entrepreneurs in XIX century Mexico. An explanation based on a theory of bounded rational choice with social embeddedness

A theory of network-entrepreneurs or "spin-off system" is presented in this paper for the creation of firms based on the community’s social governance. It is argued that firm’s capacity for accumulation depends on the presence of employees belonging to the same social/ethnic group with expectations of "inheriting" the firm and becoming entrepreneurs once they have been selected for their merits and loyalty towards their patrons. Such accumulation is possible because of the credibility of the patrons’ promises of supporting newcomers due to high social cohesion and specific social norms prevailing in the community. This theory is exemplified through the case of the Barcelonnettes, a group of immigrants from the Alps in the South of France (Provence) who came to Mexico in the XIX Century.