Polytechnic Institute of Viseu

About: Polytechnic Institute of Viseu is a education organization based out in Viseu, Portugal. It is known for research contribution in the topics: Population & Agriculture. The organization has 392 authors who have published 989 publications receiving 14134 citations. The organization is also known as: IPV.

Social media use for travel purposes: a cross cultural comparison between Portugal and the UK

Abstract: Social media plays an important role in travelers’ planning and decision-making. Research has highlighted that the use of social media on travel planning may differ among countries, whereas culture may explain those differences. This article explores the use of social media for travel and compares United Kingdom and Portuguese citizens based on Hofstede’s cultural dimensions. Results revealed that travelers from both countries use social media essentially before travelling yet, some differences were found regarding the use after traveling and between social media consumption and creation. Travel marketers can use this knowledge to adapt social media strategies to country specific situations.

The fuzzy power flow revisited

Abstract: The idea behind the first proposal of the fuzzy power flow (FPF) was to analyze the impact of the uncertainties in load and generation at the power flow level, when no statistical information is available. Further development of the field addressed the optimal power flow problem and the use of fuzzy methodologies to help planners of the composite generation- transmission system. In a market environment, transmission system adequacy may be defined as the ability of the system to meet reasonable demands for the transmission of electricity. The starting point of this paper is that FPF can be used as a tool to quantify this adequacy, without the need of making too many assumptions about load and generation uncertainties. However, some changes in the basic concept of the FPF are needed in order to accomplish this task - part of the paper is devoted to the description of the adequate formulation. We'll also show that this formulation can be used both in the normal operation situation and in the reliability evaluation of the transmission system. An illustrative example completes the paper.

Modeling and simulation of the hot-pressing process in the production of medium density fiberboard (mdf)

Abstract: A mathematical model is presented that describes heat and moisture transfer during the hot-pressing of MDF. The model includes conduction of heat between the press platens and the central layer of the mattress, phase change of water from the adsorbed to the vapor state and the convective heat and mass transfer through the edges of the mattress. This approach results in a three-dimensional unsteady-state problem in which the properties of the wood fibers, water and the wood-water system are dependent on temperature, mattress moisture content and steam pressure. For solving this problem, a finite difference scheme is used for the discretization of-spatial variables and the resulting set of ordinary differential equations is solved using an appropriated ODE solver. This theoretical model is used to predict the evolution of temperature, moisture content, steam pressure and relative humidity with time at a given position in the mattress under typical operating conditions. Several plots are shown displ...