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2012
Antunes, R., F. Coito, and H. Duarte-Ramos. "Improving Operator Performance through the Use of a Multivariable Human-Machine Control Strategy." Technological Innovation for Value Creation (2012): 95-104. Abstract
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Azevedo, {Susana G. }, Helena Carvalho, Susana Duarte, and V. Cruz-Machado. "Influence of green and lean upstream supply chain management practices on business sustainability." Ieee Transactions On Engineering Management. 59 (2012): 753-765. Abstract

Green and lean paradigms have been adopted by companies in order to manage their relationships with suppliers in a supply chain management context, but nearly always separately and with little understanding of their influence on company performance. This paper proposes a theoretical framework for the analysis of the influence of green and lean upstream supply chain management practices on the sustainable development of businesses. To attend this objective, a set of performance measures covering economic (operational cost, environmental cost, and inventory cost), environmental (business wastage, green image, and CO 2 emission), and social (corruption risk, supplier screening and local supplier) perspectives is proposed. An explanatory case study was conducted at a Portuguese automaker to test qualitatively the validity of the proposed theoretical framework. From the case study, a model is suggested, which encompasses the relationships between green and lean upstream supply chain practices and sustainable business development.

Barroso, Telma, Raquel Viveiros, Margarida Coelho, Teresa Casimiro, Ana M. Botelho do Rego, and Ana Aguiar-Ricardo. "Influence of poly(N-isopropylacrylamide) and poly(N,N′-diethyl acrylamide) coatings on polysulfone/polyacrylonitrile-based membranes for protein separation." Polymers for Advanced Technologies. 23 (2012): 1381-1393. AbstractWebsite

Herein we describe the design and the assembly of temperature sensitive polysulfone (PS)/polyacrylonitrile (PAN) blend membranes using supercritical fluid technology. Blended membranes were prepared using the CO2-assisted phase inversion method, and their pores were coated with two thermoresponsive hydrogels-poly(N-isopropylacrylamide) (PNIPAAm) and poly(N,N′-diethylacrylamide) (PDEAAm). Permeation experiments of bovine serum albumin (BSA) and lysozyme (LYS) solutions were used to evaluate the performance and temperature-responsive behavior of coated membranes. While membranes coated with PNIPAAm presented similar protein permeation profiles at temperatures below and above its lower critical solution temperature, PDEAAm coating imparted a temperature-responsive behavior to PS/PAN (90:10) membranes and selective permeation of proteins with different sizes. Copyright © 2011 John Wiley & Sons, Ltd.

Azevedo, S. A., K. Govindan, H. Carvalho, and V. Cruz-Machado. "An integrated model to assess the leanness and agility of the automotive industry." Resources, Conservation and Recycling. 66 (2012): 85-94. AbstractWebsite

The main objective of this paper is to propose an index to assess the agility and leanness of individual companies and the corresponding supply chain. The index is named Agilean and is obtained from a set of Agile and Lean supply chain practices integrated in an assessment model. The Delphi technique is used to develop a series of weighted Agile and Lean {SCM} practices and also the importance of paradigms through experts in automotive research topics. As a way to illustrate the application of the index and find out if it returns return meaningful values, a case study is presented. The case study results confirm the quite easy applicability of the suggested Agilean index in a supply chain real-world setting. This index makes it possible to assess the companies and corresponding supply chain Agile and Lean behaviour, which is translated into an index score to compare competing companies and supply chains.

Alagador, D., M. Triviño, J. O. Cerdeira, R. Brás, M. Cabeza, and M. B. Araújo. "Linking like with like: Optimising connectivity between environmentally-similar habitats." Landscape Ecology. 27 (2012): 291-301. Abstract
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Geng, Yong, Pedro L. Almeida, João L. Figueirinhas, Eugene M. Terentjev, and Maria H. Godinho. "Liquid crystal beads constrained on thin cellulosic fibers: electric field induced microrotors and N–I transition." Soft Matter. 8.13 (2012): 3634-3640. Abstract
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Abdollahvand, S., J. Goes, L. B. Oliveira, L. Gomes, and N. Paulino. "Low phase-noise temperature compensated self-biased ring oscillator." Circuits and Systems (ISCAS), 2012 IEEE International Symposium on. IEEE, 2012. 2489-2492. Abstract
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Inácio, David, João Pina, João Martins, Mário Ventim Neves, and Alfredo Álvarez. "Lumped Parameters Equivalent Circuit of a Superconducting Hysteresis Motor." EUCAS Conference 2011. Vol. 36. 2012. 975-979. Abstract

The potential advantage of using superconducting materials in electrical devices is well described in the literature. The electromagnetic properties of these materials make them unique for several applications, such as, e.g. electrical machines and drives, fault current applications, or superconducting magnetic energy storage. In the development of electromechanical conversion devices, superconducting materials are used foreseeing mainly a decrease in the device dimensions or a performance improvement for the same active volume. To guarantee a good application of this kind of materials it is important to describe and model the phenomena that characterize their operation under different regimes. In this paper, a study based in FEM simulations of a motor with bulk superconductor in the rotor is carried out, with the purpose of understand, quantify and qualify which phenomena are present in the different regimes of the motor, leading to obtaining an equivalent electrical circuit with lumped parameters.

Pais, Tiago Cardal, and Paula Amaral. "Managing the tabu list length using a fuzzy inference system: an application to examination timetabling." Annals of Operations Research. 194 (2012): 341-363. Abstract
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Ribeiro, AR, I. Martinho, JB Tillak, I. Bernacka-Wojcik, D. Barata, PAS Jorge, H. Águas, and AG Oliva. "Microfluidic chip for spectroscopic and refractometric analysis." OFS2012 22nd International Conference on Optical Fiber Sensor. International Society for Optics and Photonics, 2012. 84211Y. Abstract
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Pina, João, Pedro Pereira, Gonçalves A. Pronto, Pedro Arsénio, and Tiago Silva. "Modelling and Simulation of Inductive Fault Current Limiters." Physics Procedia. 36 (2012): 1248-1253. AbstractWebsite

Inductive superconducting fault current limiters have already demonstrated their technical viability in electrical networks. Its architecture and robustness make them potentially adequate for distribution networks, and this type of devices is considered as an enabling technology for the advent of embedded generation with renewable energy sources. In order to promote the growth and maturity of these superconducting technologies, fast design tools must be developed, allowing simulating devices with different materials in grids with diverse characteristics. This work presents advances in the development of such tool, which, at present stage, is an effective alternative to software simulations by finite elements methods, reducing dramatically computation time. The algorithms are now compared with experimental results from a laboratory scale prototype, showing the need to refine them.

Almeida, Pedro, Yong Geng, Eugene Terentjev, and Maria Helena Godinho Necklaces of Liquid Crystal Beads: Nematic Drops Constrained on Thin Cellulosic Fibers. APS Meeting Abstracts., 2012. Abstract
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Smith, AS, R. Araújo, and O. Mateus. "A new plesiosauroid from the Toarcian (Lower Jurassic) of Alhadas, Portugal." Acta Palaeontologica Polonica. 57 (2012): 257-266. Abstract
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Bras, Joana L. A., Victor D. Alves, Ana Luisa Carvalho, Shabir Najmudin, Jose A. M. Prates, Luis M. A. Ferreira, David N. Bolam, Maria Joao Romao, Harry J. Gilbert, and Carlos M. G. A. Fontes. "Novel Clostridium thermocellum Type I Cohesin-Dockerin Complexes Reveal a Single Binding Mode." The Journal of biological chemistry. 287 (2012): 44394-405.Website
Martins, Rodrigo F. P., Arman Ahnood, Nuno Correia, Luís MNP Pereira, Raquel Barros, Pedro MCB Barquinha, Ricardo Costa, Isabel M. M. Ferreira, Arokia Nathan, and Elvira EMC Fortunato. "Recyclable, Flexible, Low‐Power Oxide Electronics." Advanced Functional Materials (2012). Abstract
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Cardoso, Alberto, M. & S. Vieira, and P. Gil. "A Remote and Virtual Lab with Experiments for Secondary Education, Engineering and Lifelong Learning Courses." International Journal of Online Engineering. 8 (2012): 49-54. Abstract
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Neves, Nuno, Raquel Barros, Elsa Antunes, Isabel Ferreira, Joao Calado, Elvira Fortunato, and Rodrigo Martins. "Sintering Behavior of Nano‐and Micro‐Sized ZnO Powder Targets for rf Magnetron Sputtering Applications." Journal of the American Ceramic Society. 95.1 (2012): 204-210. Abstract
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Botas, J. D., and H. Águas. "The Stiffness of Syntactic Metal-Matrix Composites: A Statistical Model." ISRN Ceramics. 2011 (2012). Abstract
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Carvalho, H., A. P. Barroso, V. H. Machado, S. G. Azevedo, and V. Cruz-Machado. "Supply chain redesign for resilience using simulation." Computers & Industrial Engineering. 62 (2012): 329-341. AbstractWebsite

Supply chains are facing numerous changes that are contributing to increasing their complexity and vulnerability to disturbances, therefore, to survive, supply chains must be resilient. The paper presents a supply chain simulation study for a real case concerned with the Portuguese automotive supply chain. The subset automotive supply chain involved in the case study is a three-echelon supply chain, composed by one automaker, two 1st-tier suppliers, two 2nd-tier suppliers, and one outsource entity. The purpose of the study is to evaluate alternative supply chain scenarios for improving supply chain resilience to a disturbance and understanding how mitigation strategies affect each supply chain entity performance. Two strategies widely used to mitigate disturbance negative effects on supply chains were considered and six scenarios were designed. The scenarios differ in terms of presence or absence of a disturbance in one hand and presence or absence of a mitigation strategy in other hand. To evaluate the scenarios designed, two performance measures were defined per supply chain entity, Lead Time Ratio and Total Cost.

Carvalho, H., S. A. Azevedo, and V. Cruz-Machado. "Supply chain resilience: an empirical model." Euroma 2012. Amsterdam, Netherlands 2012. Abstract

This paper proposes a model for management of supply chain resilience. To this end the structured content analysis of media news is used to analyze a sample constituted by sixty two documents containing evidences of seventy seven companies that were affected by the Japan 2011 earthquake. The sample provides evidences that companies failed to sustain their operations mainly because capacity shortages and material shortages. Also provides empirical evidence of twelve resilience practices to reduce the disturbance severity and the recovery time. Based on these findings four propositions were made and aggregated to propose a model for supply chain resilience management.

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon deposited on c-Si: Effect of the substrate temperature during deposition." PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11. Eds. S. Pizzini, G. Kissinger, H. YamadaKaneta, and J. Kang. Vol. 9. Physica Status Solidi C-Current Topics in Solid State Physics, 9. European Mat Res Soc (E-MRS), 2012. 2198-2202. Abstract

Samples of doped and undoped a-Si: H were deposited at temperatures ranging from 100 degrees C to 350 degrees C and then submitted to different dehydrogenation temperatures (from 350 degrees C to 550 degrees C) and times (from 1 h to 4 h). a-Si: H films were characterised after deposition through the measurements of specific material parameters such as: the optical gap, the conductivity at 25 degrees C, the thermal activation energy of conductivity and its hydrogen content. Hydrogen content was measured after each thermal treatment. Substrate dopant contamination from phosphorus-doped a-Si thin films was evaluated by SIMS after complete dehydrogenation and a junction depth of 0.1 mu m was obtained. Dehydrogenation results show a strong dependence of the hydrogen content of the as-deposited film on the deposition temperature. Nevertheless, the dehydrogenation temperature seems to determine the final H content in a way almost independent from the initial content in the sample. H richer films dehydrogenate faster than films with lower hydrogen concentration. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon deposited on c-Si: Effect of the substrate temperature during deposition." PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11. Eds. S. Pizzini, G. Kissinger, H. YamadaKaneta, and J. Kang. Vol. 9. Physica Status Solidi C-Current Topics in Solid State Physics, 9. European Mat Res Soc (E-MRS), 2012. 2198-2202. Abstract

Samples of doped and undoped a-Si: H were deposited at temperatures ranging from 100 degrees C to 350 degrees C and then submitted to different dehydrogenation temperatures (from 350 degrees C to 550 degrees C) and times (from 1 h to 4 h). a-Si: H films were characterised after deposition through the measurements of specific material parameters such as: the optical gap, the conductivity at 25 degrees C, the thermal activation energy of conductivity and its hydrogen content. Hydrogen content was measured after each thermal treatment. Substrate dopant contamination from phosphorus-doped a-Si thin films was evaluated by SIMS after complete dehydrogenation and a junction depth of 0.1 mu m was obtained. Dehydrogenation results show a strong dependence of the hydrogen content of the as-deposited film on the deposition temperature. Nevertheless, the dehydrogenation temperature seems to determine the final H content in a way almost independent from the initial content in the sample. H richer films dehydrogenate faster than films with lower hydrogen concentration. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Carvalho, T., V. Augusto, A. R. Bras, N. M. T. Lourenco, CAM Afonso, S. Barreiros, N. T. Correia, P. Vidinha, E. J. Cabrita, C. J. Dias, M. Dionisio, and B. Roling. "Understanding the Ion Jelly Conductivity Mechanism." Journal of Physical Chemistry B. 116 (2012): 2664-2676. Abstract
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Antão, A. N., Nuno M. Vicente da Silva, da Costa Guerra, and R. Delgado. "An upper bound-based solution for the shape factors of bearing capacity of footings under drained conditions using a parallelized mixed f.e. formulation with quadratic velocity fields." Computers and Geotechnics. 41 (2012): 23-35. Abstract

A strict upper-bound limit analysis finite element formulation is used to estimate shape factors s_gamma and s_q for determining the bearing capacity of shallow foundations using the classic bearing capacity formula. The finite element formulation uses a quadratic approximation for the velocity field, an extension of a previously published Augmented Lagrangian formulation with a linear velocity field, and was implemented for a parallel processing environment. Results from determining the limit loads under three-dimensional conditions are presented and compared with previously published data. The results obtained allow a strict upper-bound determination of the shape factors. Furthermore, a practical proposal for these factors is made and compared with other proposals made by other authors.