Reduced-order thermodynamic models for servo-pneumatic actuator chambers

This paper discusses thermodynamic models of air inside pneumatic actuator chambers. In servopneumatics common practice, these models are simplified by neglecting the temperature dynamics. Classical models in literature assume temperature inside the pneumatic chamber to be either constant or to follow a polytropic law. Furthermore, the mixing process of air entering the chamber and heat transfer between air and cylinder walls is often neglected or only implicitly taken into account. This work evaluates the impact of these simplifications/order reductions in the prediction of pressure inside the actuator chamber. Classical models are compared with several others taking into account not only the mixing process but also explicitly including heat transfer between air and cylinder walls. Simulation studies show that the reduced order models proposed in this paper can lead to a mean square error in pressure prediction of only 10% of the one obtained using classical models

Telecommuting potential analysis

Commuting is a problem for developed societies that translates into economic, social and environmental losses. This study is set to explore the potential of telecommuting. The empirical study started with interviews to build a survey that was answered by 126 Lisbon commuters. Results show interviewees perceived telecommuting consequences are in line with extant research and that attitudes towards telecommuting (productivity, and cost savings) are predictors of the intention to accept telecommuting offers. Likewise, professional tenure and work-to-home stress foster a more favourable attitude related to productivity / quality of working life while displacement mode (active) and home-to-work stress foster a more favourable attitude related with cost savings. The study concludes that there is considerable potential for telecommuting and that the process of implementing telecommuting as an HRM policy is doable based on the attitudes identified in the model developed.info:eu-repo/semantics/acceptedVersio

Tuned liquid dampers simulation for earthquake response control of buildings

This paper is focused on the study of an earthquake protection system, the Tuned Liquid Damper (TLD), which can, if adequately designed, reduce earthquake demands on buildings. This positive effect is accomplished taking into account the oscillation of the free surface of a fluid inside a tank (sloshing). The behaviour of an isolated Tuned Liquid Damper, subjected to a sinusoidal excitation at its base, with different displacement amplitudes, was studied by finite element analysis. The efficiency of the TLD in improving the seismic response of an existing building, representative of modern architecture buildings in southern European countries was also evaluated based on linear dynamic analyses

Does customer-based reputation add to social and mass media reputation in judging social responsibility of banks?

Purpose: Reputation is a critical asset for finance and banking organizations where the mere suspicion of a problem suffices to trigger media turmoil with high risk of market share losses. Investing in media to build reputation has been therefore a priority for banks. However, another source of reputation may stem from direct front-office contact and it is yet unknown to which extent it plays a role when confronted with the widespread social and mass media reach. This study aims at testing the extent of the importance of customer-based reputation, as against media-based reputation, in explaining customer outcomes.info:eu-repo/semantics/publishedVersio

3D-mappings and their approximations by series of powers of a small parameter

Conformal mappings in the plane are closely linked with holomorphic functions and their property of complex differentiability. In contrast to the planar case, in higher dimensions the set of conformal mappings consists only of M¨obius transformations which are not monogenic and therefore also not hypercomplex differentiable. But due to the equivalence between being hypercomplex differentiable and being monogenic the question arises if from this point of view monogenic functions can still play a special role for other types of 3D-mappings, for instance, for quasi-conformal ones. Our goal is to present a case study of an approach to 3Dmappings which is an extension of ideas of L. V. Kantorovich to the 3-dimensional case by using para-vectors and a suitable series of powers of a small parameter. In the case of the application of Bergman’s reproducing kernel approach (BKM) to 3D- mapping problems the recovering of the mapping function itself and its relation to the kernel function is still an open problem. The approach that we present here avoids such difficulties and leads directly to an approximation by monogenic polynomials depending on that small parameter.Fundação para a Ciência e a Tecnologia (FCT

Assessing Reading Abilities of Mechanical Engineering College Students: A Prospecting Study*

Reading is a basic competence that students have to master to be successful. Despite this fact, recent studies show that there may be a significant decline in the reading abilities of college students, one of the most educated segments of any population. This work is a prospecting study regarding the assessment of reading abilities of college students, namely in the context of Engineering education. Based on an existing screening test for assessing reading difficulties of children and teenagers, this work presents the results obtained by administrating that test to students at a top engineering institution in Portugal. An outcome of this study is the determination of a time range suitable for a massive, time limited, use of the previously mentioned test to assess college students, thus enabling a basic tool that will permit, in future works, to screen reading abilities in wider college populations. This work also shows evidence that ca. 20% of college students present a poor reading performance, revealing a strong need for monitoring college students’ reading abilities along different generations