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2014
Rybarczyk, Y., Coelho, T., Cardoso, T., and De Oliveira R. "Effect of avatars and viewpoints on performance in virtual world: efficiency vs. telepresence." EAI Endorsed Transactions on Creative Technologies. 14.1 (2014): e4.Website
Rybarczyk, Y., T. Coelho, T. Cardoso, and R. De Oliveira. "Effect of avatars and viewpoints on performance in virtual world: efficiency vs. telepresence." EAI Endorsed Transactions on Creative Technologies. 14.1 (2014): e4. Abstract

An increasing number of our interactions are mediated through e-technologies. In order to enhance the human’s feeling of presence into these virtual environments, also known as telepresence, the individual is usually embodied into an avatar. The natural adaptation capabilities, underlain by the plasticity of the body schema, of the human being make a body ownership of the avatar possible, in which the user feels more like his/her virtual alter ego than himself/herself. However, this phenomenon only occurs under specific conditions. Two experiments are designed to study the human’s feeling and performance according to a scale of natural relationship between the participant and the avatar. In both experiments, the human-avatar interaction is carried out by a Natural User Interface (NUI) and the individual’s performance is assessed through a behavioural index, based on the concept of affordances, and a questionnaire of presence The first experiment shows that the feeling of telepresence and ownership seem to be greater when the avatar’s kinematics and proportions are close to those of the user. However, the efficiency to complete the task is higher for a more mechanical and stereotypical avatar. The second experiment shows that the manipulation of the viewpoint induces a similar difference across the sessions. Results are discussed in terms of the neurobehavioral processes underlying performance in virtual worlds, which seem to be based on ownership when the virtual artefact ensures a preservation of sensorimotor contingencies, and simple geometrical mapping when the conditions become more artificial.

Ramos, Pinho A., Válter J. G. Lúcio, and Duarte M. V. Faria. "The effect of the vertical component of prestress forces on the punching strength of flat slabs." Engineering Structures. 76 (2014): 90-98. Abstract

The use of prestress in flat slabs is a common solution, mainly because it allows larger spans and thinner slabs. Nevertheless, smaller thicknesses near the slab-column connections, along with the superposition of high shear and flexural stresses, arise the question of the slab capacity to resist punching. The punching failure results from the superposition of shear and flexural stresses near the column, and is associated to the formation of a pyramidal plug of concrete which punches through the slab. It is a local and brittle failure. The use of prestress can increase the punching capacity of flat slabs-column connections.This work presents the experimental analysis of flat slab specimens with tendons under punching. Nine slabs were tested using unbonded prestress with high strength steel tendons. The influences on the punching capacity of the vertical component of the prestress forces resulting from inclined tendons near the column and their distance to the column are analysed. The in-plane compression force due to prestress was not applied to the slabs, in order to evaluate only the deviation force influence. This work aims to improve the understanding of the behaviour of prestressed flat slabs under punching load in order to properly evaluate the punching resistance of this kind of structures. The experimental punching loads are compared with the provisions of EC2, ACI 318-11 and MC2010. © 2014 Elsevier Ltd.

Russo, J., O. Mateus, M. Marzola, and A. Balbino. "Eggs and eggshells of crocodylomorpha from the Late Jurassic of Portugal." Journal of Vertebrate Paleontology. Program and Abstracts, 2014 (2014): 218.russo_et_al_2014eggs_crocodylomorpha_portugal.pdf
Marinheiro, J., O. Mateus, A. Alaoui, F. Amani, M. Nami, and C. Ribeiro. "Elephas and other vertebrate fossils near Taghrout, Morocco." Journal of Vertebrate Paleontology. Program and Abstracts, 2014 (2014): 178.marinheiro_et_al._2014_elephas_and_other_vertebrate_fossils_near_taghrout.pdf
Palma, L., R. T. Rato, and AG Batista Empirical Models for Horizontal Saccadic Eye Movements. Conference on Human System Interaction. 10.1109/HSI.2014.6860450, 2014.
Ferrás, L., M. Rebelo, and M. L. Morgado. "Fractional modelling of Pennes' bioheat equation using distributed order differential equations." 14th International Conference on Computational and Mathematical Methods in Science and Engineering (CMMSE 2014). 2014.
Rocha, H. Games and the learning of mathematics outside the classroom. Proceedings of the International Conference on Education and New Learning Technologies. Barcelona, Spain: EduLearn, 2014. Abstract

GAMES AND THE LEARNING OF MATHEMATICS OUTSIDE THE CLASSROOM
H. Rocha

Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia (PORTUGAL)

Playing games is a recreational activity that is also highly recognized as a potentially rich activity for the teaching and learning. It is an activity that involves the recognition and observance of rules, as well as the development of strategies to achieve victory. It is thus an activity that encourages compliance with rules but also the development of learning and therefore has a socializing character while stimulating critical thinking and analysis of situations. This is why many authors think about playing games as a problem-solving activity with great potential for the learning of mathematics. However, a review of the literature suggests that mathematical learning does not always occur, pointing to the relevance of the specific features of the game and the circumstances in which it is used. Looking to contribute to a better understanding of these issues, the project that was the basis of this study focuses on the use of games by middle school students, intending to promote their mathematical learning in a voluntary and informal context, outside the classroom. The games were available in MatLab, a room of the school supervised by mathematics teachers, which students could visit in their leisure time. In this communication I intend to analyze how the visits to MatLab contributed to the mathematical learning of students, considering the influence of specific characteristics of the games and the atmosphere created in MatLab, given the students’ previous mathematical knowledge.

The study adopts a qualitative and interpretative methodological approach, undertaking two student case studies. Data collection was completed over three months and included observation of twenty visits of these students to MatLab. Data collection was made through the development of a logbook, audio record of the students’ visits and two interviews to the students and to their teacher. Data analysis was based on the evidence gathered in the light of the problem under study.

The conclusions reached stress the importance of certain features of the games to promote student engagement, leading to a desire for self-improvement, very important for the development of sustained learning. Computer games have proven to have a stronger potential to engage students than board games. Nevertheless, the most important characteristics of a game seem to be related to the possibility of playing at different mathematical levels (without getting blocked by lack of knowledge) and to the possibility of keep getting better marks (without the existence of a maximum level from which evolution is not possible). In what concerns to achievement in mathematics’ classes, the students’ teacher reports an improvement in mathematics knowledge (more evident in the average achiever student) as well as an increase in students’ involvement in class work (more evident in the low achiever student).

keywords: game-based learning, mathematics, informal learning.

Hayashi, S., R. Redelstorff, O. Mateus, M. Watabe, and K. Carpenter. "Gigantism of stegosaurian osteoderms." Journal of Vertebrate Paleontology. Program and Abstracts, 2014 (2014): 145.hayashi_et_al_2014_gigantism_of_stegosaurian_osteoderms.pdf
Donovan, T. O., J. Brown, F. Bsching, Alberto Cardoso, J. Cecílio, J. d O, P. Furtado, P. Gil, A. Klein, W. Poettner, U. Roedig, Jorge Sá Silva, R. M. Silva, C. Sreenan, V. Vassiliou, L. Wolf, and Z. Zinonos. "The GINSENG System for Wireless Monitoring and Control: Design and Deployment Experiences." ACM Transactions on Sensor Networks (2014): n/a. Abstract

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Micaelo, Rui, J. Ribeiro, and M. Azevedo. "Hot-mix asphalt compaction evaluation with field tests." The Baltic Journal of Road and Bridge Engineering. 9.4 (2014): 306-316.Website
Clement, Thibault, Antonio Pinho Ramos, Miguel Fernandez Ruiz, and Aurelio Muttoni. "Influence of prestressing on the punching strength of post-tensioned slabs." Engineering Structures. 72 (2014): 56-69. Abstract

Previous researches on punching of post-tensioned slabs have shown a number of phenomena significantly influencing their strength and behaviour. However, no general agreement is yet found on a physical theory (either in codes of practice or in design models) suitably describing the influence of prestressing and how should it be accounted on the punching shear behaviour. In this paper, the authors present the results of tests on 15 slabs (3000. ??. 3000. ??. 250. mm) tested to failure under different loading conditions. The aim of the tests was to investigate in a separate manner the different actions induced by prestressing on the punching shear strength (in-plane forces, bending moments and bonded tendons). These results are finally investigated on the basis of the physical model of the Critical Shear Crack Theory. The fundamentals of this theory are presented and adapted to post-tensioned slabs, providing a rational explanation of the observed phenomena and measured strengths. ?? 2014 Elsevier Ltd.

Rocha, H. The influence of teacher’s knowledge for teaching mathematics with technology on the implementation of investigation tasks. Proceedings of 8th International Technology, Education and Development Conference. Valencia, Spain: INTED, 2014.
Ribeiro, D., M. Freitas, SM Tomé, AM Silva, G. Porto, E. J. Cabrita, M. M. Marques, and E. Fernandes. "Inhibition of LOX by flavonoids: a structure-activity relationship study." European Journal of Medicinal Chemistry. 72 (2014): 137-145. AbstractWebsite

The lipoxygenase (LOX) products have been identified as mediators of a series of inflammatory diseases, namely rheumatoid arthritis, inflammatory bowel disease, psoriasis, allergic rhinitis, atherosclerosis and certain types of cancer. Hence, LOX inhibitors are of interest for the modulation of these phenomena and resolution of the inflammatory processes. During LOX activity, peroxyl radical complexes are part of the reaction and may function as sources of free radicals. Thus antioxidants, such as flavonoids, capable of inhibiting lipid peroxidation and scavenging free radicals, may act as LOX inhibitors. The aim of this work was to assess the structure–activity relationship among a series of flavonoids concerning 5-LOX inhibition, through a systematic study of the inhibition of the formation of LTB4 in human neutrophils. The type of inhibition of the flavonoids was further studied using soybean LOX, type I, and Saturation Transfer Difference 1H NMR (STD-1H NMR) was used to characterize the binding epitopes of the compounds to LOX-1. The obtained results reinforce flavonoids as effective inhibitors of LTB4 production in human neutrophils. It was also possible to establish a structure/activity relationship for the inhibitory activity and the type of inhibition.

Rybarczyk, Yves, Tiago Cardoso, João Rosas, and Luis M. Camarinha-Matos Innovative and Creative Developments in Multimodal Interaction Systems: 9th Ifip Wg 5.5 International Summer Workshop on Multimodal Interfaces, Enterface 2013, Lisbon, Portugal, July 15-August 9, 2013, Proceedings. Springer, 2014. Abstract

This book contains the outcome of the 9th IFIP WG 5.5 International Summer Workshop on Multimodal Interfaces, eNTERFACE 2013, held in Lisbon, Portugal, in July/August 2013. The 9 papers included in this book represent the results of a 4-week workshop, where senior and junior researchers worked together on projects tackling new trends in human-machine interaction (HMI). The papers are organized in two topical sections. The first one presents different proposals focused on some fundamental issues regarding multimodal interactions, i.e., telepresence, speech synthesis and interactive modeling. The second is a set of development examples in key areas of HMI applications, i.e., education, entertainment and assistive technologies.

Carvalho, T., V. Augusto, A. Rocha, N. M. T. Lourenco, N. T. Correia, S. Barreiros, P. Vidinha, E. J. Cabrita, and M. Dionisio. "Ion Jelly Conductive Properties Using Dicyanamide-Based Ionic Liquids." Journal of Physical Chemistry B. 118.31 (2014): 9445-59. AbstractWebsite

The thermal behavior and transport properties of several ion jellys (IJs), a composite that results from the combination of gelatin with an ionic liquid (IL), were investigated by dielectric relaxation spectroscopy (DRS), differential scanning calorimetry (DSC), and pulsed field gradient nuclear magnetic resonance spectroscopy (PFG NMR). Four different ILs containing the dicyanamide anion were used: 1-butyl-3-methylimidazolium dicyanamide (BMIMDCA), 1-ethyl-3-methylimidazolium dicyanamide (EMIMDCA), 1-butyl-1-methylpyrrolidinium dicyanamide (BMPyrDCA), and 1-butylpyridinium dicyanamide (BPyDCA); the bulk ILs were also investigated for comparison. A glass transition was detected by DSC for all materials, ILs and IJs, allowing them to be classified as glass formers. Additionally, an increase in the glass transition temperature upon dehydration was observed with a greater extent for IJs, attributed to a greater hindrance imposed by the gelatin matrix after water removal, rendering the IL less mobile. While crystallization is observed for some ILs with negligible water content, it was never detected for any IJ upon thermal cycling, which persist always as fully amorphous materials. From DRS measurements, conductivity and diffusion coefficients for both cations (D+) and anions (D–) were extracted. D+ values obtained by DRS reveal excellent agreement with those obtained from PFG NMR direct measurements, obeying the same VFTH equation over a large temperature range (ΔT ≈ 150 K) within which D+ varies around 10 decades. At temperatures close to room temperature, the IJs exhibit D values comparable to the most hydrated (9%) ILs. The IJ derived from EMIMDCA possesses the highest conductivity and diffusion coefficient, respectively, 10–2 S·cm–1 and 10–10 m2·s–1. For BMPyrDCA the relaxational behavior was analyzed through the complex permittivity and modulus formalism allowing the assignment of the detected secondary relaxation to a Johari–Goldstein process. Besides the relevant information on the more fundamental nature providing physicochemical details on ILs behavior, new doorways are opened for practical applications by using IJ as a strategy to produce novel and stable electrolytes for different electrochemical devices.

Cardoso, Tiago, João Gameiro, João Rosas, and Yves Rybarczyk. "KINECT-SIGN: Teaching Sign Language to "Listeners" through a Game." nternational Summer Workshop on Multimodal Interfaces - Enterface 2013 Proceedings. Springer, 2014. Abstract

Sign language is the hearing impaired form of communicating with other people, including listeners. Most cases, impaired people have learned sign language form childhood. The problem arises when a listener comes in contact with an impaired person. For instances, if a couple has a child which is impaired, the parents find a challenge to learn the sign language. In this article, a new playful approach to assist the listeners to learn sign language is proposed. This proposal is a serious game composed of two modes: School-mode and Competition-mode. The first offers a virtual school where the user learns to sign letters and the second offers an environment towards applying the learned letters. Behind the scenes, the proposal contains a sign language recognition system, based on three modules: 1 – the standardization of the Kinect depth camera data; 2 – a gesture library relying on the standardized data; and 3 – the real-time recognition of gestures. A prototype was developed – Kinect-Sign – and tested in a Portuguese Sign-Language school and on eNTERFACE’13 resulting in a joyful acceptance of the approach.

Oitavem, I., and H. Rocha. "MATER: a matemática como uma perspetiva sobre o planeta Terra." Educação e Matemática. 126 (2014): 36-37.
Rocha, H. Mathematics teaching in Education and Training Courses. Proceedings of the International Conference on Education and New Learning Technologies. Barcelona, Spain: EduLearn, 2014. Abstract

MATHEMATICS TEACHING IN EDUCATION AND TRAINING COURSES
H. Rocha

Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia (PORTUGAL)

Education and Training Courses have been specifically designed to the high number of young people in a situation of school dropout and in transition to working life, particularly those who enter the labor market early with insufficient levels of schooling and professional training. Mathematics is one of the curriculum components of these courses, for its contribution to the exercise of citizenship in a democratic society. Being an important part of the cultural legacy of our society is too often seen by students as a source of exclusion. It is known that young people who enter these courses often had an experience of underachievement in the discipline, what justifies that motivating students is at once the great challenge faced by the teacher. The program suggests taking a more concrete and linked to reality approach, allowing students to learn to recognize the mathematics in the world around them and using technology to promote that learning. However, it is the teacher who is responsible for managing its implementation, shaping the learning situations and integrating them in a coherent and articulated way in the specific course that students attend. In what concerns to assessment, the program also takes into account the usual characteristics of the students. Thus, the assessment includes a strong appreciation of students’ work, its presentation and discussion and further improvement of that work. The directions given to the teacher diverge from the traditional option of the evaluation test, providing guidelines to the form that each evaluation can take depending on the contents in study. However, once again, the teacher's role in curriculum management is not neglected, being valued the adequacy of proposals to the characteristics of the students.
The study presented here had as its main goal to analyze and understand the choices made by the teacher during the different stages of his practice, giving attention to the dilemmas he faced and to the reasons he took into account when making decisions.

The study adopts a qualitative and interpretative methodological approach, undertaking one teacher case study. Data collection included semi-structured interviews, classroom observation and document collection. Data analysis was based on the evidence gathered in the light of the problem under study.

The conclusions of the study point to the important role of technology and suggest that the reduction of prerequisites, the intention of taking into account the students’ interests and the desire of improving students culture is central in what concerns to task selection; while the active involvement of students characterized the implementation of the classes. The dilemmas faced by the teacher focus mainly on the relative importance and on the demanding level that he should give to each content, as well as the articulation that he should promote between formal and intuitive knowledge. In what concerns to assessment, the results achieved highlight the impact that students ideas can have on teacher’s practice, conducting to the inclusion of tests as an assessment element, against the teacher’s intentions.

keywords: education and training courses, mathematics, innovation, technology.

Rybarczyk, Y. Mécanismes d’Appropriation Sensorimotrice de Systèmes Télérobotisés. Sarrebruck: Presses Académiques Francophones, 2014.Website
Martins, N., and M. Rebelo. "Meshfree methods for nonhomogeneous Brinkman flows." Computers and Mathematics with Applications. 68 (2014): 872-886.Website
Raposo, C. D., K. T. Petrova, and M. T. Barros. "Microwave-Assisted Protocols Applied to the Synthesis of 1′,2,3,3′,4,4′-Hexa-O-benzylsucrose." Synthetic Commun. 44.20 (2014): 3027-3036. DOI:10.1080/00397911.2014.926555.
Rebelo, M., T. Diogo, and S. McKee. "Modelling a Competitive Antibody/Antigen Chemical Reaction that Occurs in the Fluorescence Capillary-Fill Device." Progress in Industrial Mathematics at ECMI 2012. 2014.
Marinheiro, J., O. Mateus, A. Alaoui, F. Amani, M. Nami, and C. Ribeiro. "New Quaternary fossil sites from the Middle Atlas of Morocco." Comunicações Geológicas. 101, Especial I (2014): 485-488. Abstractmarinheiro_et_al_2014_new_quaternary_fossil_sites_from_the_middle_atlas_of_morocco.pdf

The paleontological richness of Morocco has been scientifically known since at least the early 20th century. The region of the Middle Atlas, more specifically the Boulemane area, has been however only sparsely studied since the 1960s when it provided vertebrate fossils from the Middle Jurassic. In September 2013, a Moroccan-Portuguese expedition to the village of Taghrout, Boulemane, made excavations in a Pleistocene fossil site that once was a small high-altitude sedimentary basin, uncharted in previous geological maps. The excavations yielded bone material from large mammals, the most common findings are elephants ascribed to Elephas, but artiodactyls, turtles, and in-situ Acheulean tools were also collected. This represents a new and important paleontological and archeological site. In addition to the discoveries of Taghrout, the expedition also retrieved Quaternary vertebrate material from a nearby cave and found new Jurassic localities, with arcosaur bones and dinosaur footprints, in El Mers.

Duarte, Duarte M., Jurgen Einpaul, António M. Ramos, Miguel {Fernandez Ruiz}, and Aurelio Muttoni. "On the efficiency of flat slabs strengthening against punching using externally bonded fibre reinforced polymers." Construction and Building Materials. 73 (2014): 366-377. Abstract

One possibility for strengthening existing flat slabs consists on gluing fibre reinforced polymers (FRPs) at the concrete surface. When applied on top of slab-column connections, this technique allows increasing the flexural stiffness and strength of the slab as well as its punching strength. Nevertheless, the higher punching strength is associated to a reduction on the deformation capacity of the slab-column connection, which can be detrimental for the overall behaviour of the structure (leading to a more brittle behaviour of the system). Design approaches for this strengthening technique are usually based on empirical formulas calibrated on the basis of the tests performed on isolated test specimens. However, some significant topics as the reduction on the deformation capacity or the influence of the whole slab (accounting for the reinforcement at mid-span) on the efficiency of the strengthening are neglected. In this paper, a critical review of this technique for strengthening against punching shear is investigated on the basis of the physical model proposed by the Critical Shear Crack Theory (CSCT). This approach allows taking into account the amount, layout and mechanical behaviour of the bonded FRP's in a consistent manner to estimate the punching strength and deformation capacity of strengthened slabs. The approach is first used to predict the punching strength of available test data, showing a good agreement. Then, it is applied in order to investigate strengthened continuous slabs, considering moment redistribution after concrete cracking and reinforcement yielding. This latter study provides valuable information regarding the differences between the behaviour of isolated test specimens and real strengthened flat slabs. The results show that empirical formulas calibrated on isolated specimens may overestimate the actual performance of FRP's strengthening. Finally, taking advantage of the physical model of the CSCT, the effect of the construction sequence on the punching shear strength is also evaluated, revealing the role of this issue which is also neglected in most empirical approaches.