Highlights of my current and past research dealing with Visualization, Medical Imaging and Computer Graphics.

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2014

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• Samuel Silva, Paula Martins, Catarina Oliveira, António Teixeira, "Quantitative Analysis of /l/ Production from RT-MRI: First Results", Proc. IberSpeech, [to appear], 2014
• Samuel Silva, António Teixeira, "Automatic Annotation of an Ultrasound Corpus for Studying Tongue Movement" , Proc. ICIAR, LNCS 8814, pp. 469--476, Vilamoura, Portugal, Oct., 2014
• Samuel Silva, Joaquim Madeira, Beatriz Sousa Santos, "Computer-Assisted Myocardial Perfusion Assessment", Proc. MediViz '14, [to appear], 2014
• Samuel Silva, Daniela Braga, António Teixeira, "AgeCI: HCI and Age Diversity", Proc. HCII 2014, LNCS 8515, pp. 179-190, June, 2014
• Samuel Silva, António Teixeira, "Systematic and Quantitative Analysis of Vocal Tract Data: Intra- and Inter-Speaker Analysis", Proc. Int. Seminar on Speech Production (ISSP), pp. 403-406, May, 2014
• Samuel Silva, António Teixeira, "RT-MRI Based Dynamic Analysis of Vocal Tract Configurations: Preliminary Work Regarding Intra- and Inter-sound Variability", Proc. Int. Seminar on Speech Production (ISSP), pp. 399-402, May, 2014
• Samuel Silva, António Teixeira, "A framework for analysis of the upper airway from real-time MRI sequences", Proc. Visualization and Data Analysis (VDA2014), pp. 901703, Feb., 2014
• João Freitas, Samuel Silva, António Teixeira, Miguel S. Dias, "Assessing the Applicability of Surface EMG to Tongue Gesture Detection", Proc. IberSpeech, [to appear], 2014
• João Freitas, Miguel Sales Dias, Samuel Silva, Catarina Oliveira, António J. S. Teixeira, "Velum Movement Detection based on Surface Electromyography for Speech Interface", Proc. BIOSIGNALS 2014 – Int Conf on Bio-inspired Systems and Signal Processing, pp. 13-20, 2014
• Nuno Almeida, Samuel Silva, António Teixeira, "Design and Development of Speech Interaction: A Methodology", Proc. HCII 2014, LNCS vol. 8511, pp. 370-381, June, 2014
• Nuno Almeida, Samuel Silva, António Teixeira, "Multimodal Multi-Device Application Supported by an SCXML State Chart Machine", Proc. EICS Workshop on Engineering Interactive Systems with SCXML, 2014
• António Teixeira, Pedro Francisco, Nuno Almeida, Carlos Pereira, Samuel Silva, "Services to Support Use and Development of Speech Input for Multilingual Multimodal Applications for Mobile Scenarios", Proc. 9th Int. Conf. on Internet and Web Applications and Services (ICIW), 2014

2013

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• Flávio Ferreira, Nuno Almeida, Ana Filipa Rosa, André Oliveira, José Casimiro Pereira, Samuel Silva, António Teixeira, "Elderly centered design for Interaction -- the case of the S4S Medication Assistant", Proc. DSAI 2013, Vigo, November, 2013
• Samuel Silva, António Teixeira, Catarina Oliveira, Paula Martins, "Towards a Systematic and Quantitative Analysis of Vocal Tract Data", Proc. InterSpeech 2013, pp. 1307-1311, August, 2013
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• Miguel Santos, Beatriz Sousa Santos, Paulo Dias, Samuel Silva, Carlos Ferreira, "Extending the H-Tree Layout Pedigree: An Evaluation", Proc. 17th International Conference on Information Visualisation (IV2013), [to appear], 2013
• Samuel Silva, António Teixeira, Catarina Oliveira, Paula Martins, "Segmentation and Analysis of Vocal Tract from MidSagittal Real-Time MRI", Proc. 9th International Conference on Image Analysis and Recognition (ICIAR 2013), LNCS 7950, pp. 459--466, June, 2013
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• António Teixeira, Flávio Ferreira, Nuno Almeida, Ana Filipa Rosa, José Casimiro Pereira, Samuel Silva, Alexandra Queirós, André Oliveira, "Multimodality and Adaptation for an Enhanced Mobile Medication Assistant for the Elderly", Proc. CHI 2013 (Extended Abstracts), 2013
• Samuel Silva, António Teixeira, "AAM Based Vocal Tract Segmentation from Real-Time MRI Image Sequences", Proc. 19th Portuguese Conference on Pattern Recognition (RecPad 2013), 2013

2012

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• Samuel Silva, Beatriz Sousa Santos, Joaquim Madeira, "Exploring Different Parameters to Assess Left Ventricle Global and Regional Functional Analysis from Coronary CT Angiography", Computer Graphics Forum, vol. 31, no.1, pp. 146--159, doi:10.1111/j.1467-8659.2012.02090.x, 2012
• Paula Martins, Samuel Silva, Catarina Oliveira, Carlos Ferreira, Augusto Silva, António Teixeira, "Polygonal Mesh Comparison Applied to the Study of European Portuguese Sounds", International Journal of Creative Interfaces and Computer Graphics, vol. 3, no. 1. pp. 28--44, doi:10.4018/jcicg.2012010103, 2012
• Paula Martins, Catarina Oliveira, Samuel Silva, António Teixeira, "Velar Movement in European Portuguese Nasal Vowels", Proc. IberSpeech 2012, pp. 231--240, 2012
• Catarina Oliveira, Maria Manuel Cunha, Samuel Silva, António Teixeira, Pedro Couto, "Acoustic analysis of European Portuguese oral vowels produced by children", Proc. IberSpeech 2012, Springer CCIS vol. 328, pp. 129--138, Madrid, Nov., 2012
• Catarina Oliveira, Paula Martins, Samuel Silva, António Teixeira, "An MRI Study of the Oral Articulation of European Portuguese Nasal Vowels", Proc. InterSpeech 2012, 2012
• Samuel Silva, Paula Martins, Catarina Oliveira, Augusto Silva, António Teixeira, "Segmentation and Analysis of the Oral and Nasal Cavities from MR Time Sequences", Proc. 8th International Conference on Image Analysis and Recognition (ICIAR 2012), LNCS 7325, pp. 214--221, 2012
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2011

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• Samuel Silva, Beatriz Sousa Santos, Joaquim Madeira, "Using Color in Visualization: A Survey", Computers \& Graphics, vol. 35, no.2, pp. 320--333, doi:10.1016/j.cag.2010.11.015, 2011
• Beatriz Sousa Santos, Paulo Dias, Samuel Silva, Carlos Ferreira, Joaquim Madeira, "Integrating User Studies into Computer Graphics-Related Courses", Computer Graphics and Applications, vol. 31 , no. 5, pp. 14--17, doi:10.1109/mcg.2011.78, 2011
• Samuel Silva, Joaquim Madeira, Beatriz Sousa Santos, "Inter-observer Variability Assessment of a Left Ventricle Segmentation Tool Applied to 4D MDCT Images of the Heart", Proc. 33rd Annual International Conference of the IEEE Engineering in Medicine and Biology Society -- EMBC 2011, pp. 3411--3414, Boston, USA, September, 2011
• Paula Martins, Catarina Oliveira, Samuel Silva, Carlos Ferreira, Augusto Silva, António Teixeira, "Tongue Segmentation from MRI images using ITK-SNAP: Preliminary Evaluation", Proc. IADIS Computer Graphics, Visualization, Computer Vision and Image Processing (CGVCVIP) 2011, pp. 3--10, Rome, Italy, July, 2011
• Paula Martins, Samuel Silva, Catarina Oliveira, Carlos Ferreira, Augusto Silva, António Teixeira, "Investigating the differences between European Portuguese sounds: An Approach using Polygonal Mesh comparison", Proc. Ibero-American Symposium on Computer Graphics (SIACG11), pp. 209--216, Faro, Portugal, June, 2011
• Samuel Silva, Beatriz Sousa Santos, Joaquim Madeira, "Left-Ventricle Global and Regional Functional Analysis from MDCT Images", Proc. Ibero-American Symposium on Computer Graphics (SIACG11), pp. 217--223, Faro, Portugal, June, 2011
• Samuel Silva, Nuno Bettencourt, Daniel Leite, João Rocha, Mónica Carvalho, Joaquim Madeira, Beatriz Sousa Santos, "Myocardial Perfusion Analysis from Adenosine-Induced Stress MDCT", Proc. 5th Iberian Conference on Pattern Recognition and Image Analysis (IbPRIA11), LNCS 6669, pp. 717--725, Las Palmas de Gran Canaria, Spain, June, 2011
• Samuel Silva, Beatriz Sousa Santos, Carlos Ferreira, Joaquim Madeira, Augusto Silva, "A preparatory study to choose similarity metrics for left-ventricle segmentations comparison", Proc. SPIE Medical Imaging 2011 --- Computer-Aided Diagnosis, vol. 7963, pp. 796326 -- 796334, doi:10.1117/12.878294, Orlando, FL, USA, Feb., 2011

2010

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• Samuel Silva, Joaquim Madeira, Beatriz Sousa Santos, Augusto Silva, "CardioAnalyser: A Software Tool for Segmentation and Analysis of the Left Ventricle from 4D MDCT Images of the Heart", Proc. 7th International Conference BioMedical Visualization (MediVis10, pp. 629--634, London, United Kingdom, July, 2010
• Beatriz Sousa Santos, Paulo Dias, Samuel Silva, Carlos Ferreira, "Wiimote as an input device in Google Earth visualization and navigation: a user study comparing two alternatives", Proc. IV10: HCI -- Human-Computer Interaction for Information Visualization, London, United Kingdom, July, 2010
• Samuel Silva, Beatriz Sousa Santos, Joaquim Madeira, Augusto Silva; "A 3D Tool for Left Ventricle Segmentation Editing", Proc. 7th International Conference on Image Analysis and Recognition (ICIAR 2010), LNCS 6112, pp. 79--88, June, 2010

2009

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• Samuel Silva, Joaquim Madeira, Beatriz Sousa Santos, "PolyMeCo: An Integrated Environment for Polygonal Mesh Analysis and Comparison", Computers \& Graphics, vol. 33, no. 2, pp. 181--191, doi:10.1016/j.cag.2008.09.014, 2009
• Beatriz Sousa Santos, Paulo Dias, Angela Pimentel, Jan-Willem Baggerman, Carlos Ferreira, Samuel Silva, Joaquim Madeira, "Head-Mounted Display versus Desktop for 3D Navigation in Virtual Reality: A User Study", Multimedia Tools and Applications, vol. 41, no. 1, pp. 161--181, doi:10.1007/s11042-008-0223-2, 2009
• Samuel Silva, Beatriz Sousa Santos, Carlos Ferreira, Joaquim Madeira, "A Perceptual Data Repository for Polygonal Meshes", Proc. 4th International Conference on Geometric Modeling and Imaging (GMAI09), pp. 207--211, Barcelona, Spain, July, 2009
• Samuel Silva, Beatriz Sousa Santos, Joaquim Madeira, Augusto Silva, "Processing, Visualization and Analysis of Medical Images of the Heart: An Example of Fast Prototyping using MeVisLab", Proc. 6th International Conference on BioMedical Visualization (MediVis09), pp. 165--170, Barcelona, Spain, July, 2009
• Samuel Silva, Beatriz Sousa Santos, Joaquim Madeira, Augusto Silva, "Left Ventricle Segmentation from Heart MDCT", Proc. 4th Iberian Conference on Pattern Recognition and Image Analysis (IbPRIA09), LNCS 5524, pp. 306--313, Póvoa do Varzim, Portugal, June, 2009
• Beatriz Sousa Santos, Paulo Dias, Samuel Silva, Carlos Ferreira, "Usability evaluation in Virtual Environments through empirical studies involving users", ACM-CHI 2009 workshop: Challenges in Evaluating Usability and User Experience in Reality Based Interaction, pp. 28--31, Boston, USA, April, 2009
• Beatriz Sousa Santos, Paulo Dias, Samuel Silva, Carlos Ferreira, Joaquim Madeira, "Introducing students to empirical methods in CG and HCI courses through user studies", EUROGRAPHICS 2009 - Education Papers, pp. 45--49, Munich, Germany, April, 2009

Before 2009

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• Beatriz Sousa Santos, Paulo Dias, Samuel Silva, et al., "Usability Evaluation in Virtual Reality: A User Study Comparing Three Different Setups", Eurographics Symposium on Virtual Environments 2008 (EGVE08), Poster, pp. 21--24, Holland, May, 2008
• Samuel Silva; Beatriz Sousa Santos; Joaquim Madeira; Carlos Ferreira, "Perceived Quality Assessment of Polygonal Meshes using Observer Studies: A New Extended Protocol", Proc. SPIE Electronic Imaging 2008: Human Vision and Electronic Imaging XIII, pp. , San Jose, CA, USA, Jan., 2008
• Frutuoso Silva, Samuel Silva, "Quality Perception of Simplified Models: NSA vs QSLIM", Proc. 3rd International Conference on Computer Graphics Theory and Applications (GRAPP 2008), pp. 74--79 , Funchal, PT, Jan., 2008
• Samuel Silva; Frutuoso Silva; Joaquim Madeira; Beatriz Sousa Santos, "Evaluation of Mesh Simplification Algorithms using PolyMeCo: A case Study", Proc. Visualization and Data Analysis 2007, pp. 64950D - 6495D-12, San Jose, CA, US, Jan. 2007
• Samuel Silva; Joaquim Madeira; Carlos Ferreira; Beatriz Sousa Santos, "Comparison of Methods for the Simplification of Mesh Models using Quality Indices and an Observer Study", Proc. Human Vision and Electronic Imaging XII, pp. 64921 L1 - 64921 L12, San Jose, CA, US, Jan., 2007
• Samuel Silva, Joaquim Madeira, Beatriz Sousa Santos, "There is More to Color Scales than Meets the Eye: A Review on the Use of Color in Visualization", Proc. 11th International Conference on Information Visualization (IV07), pp. 943--950, Zurich, Switzerland, July, 2007
• Beatriz Sousa Santos, Samuel Silva, Leonor Teixeira, Carlos Ferreira, Paulo Dias, Joaquim Madeira, "Preliminary Usability Evaluation of PolyMeCo: A Visualization Based Tool for Mesh Analysis and Comparison", Proc. GMAI 2007: Geometric Modelling and Imaging, pp. 133--139, Zurich, Switzerland, July, 2007
• Samuel Silva, Carlos Ferreira, Joaquim Madeira, Beatriz Sousa Santos, "Perceived Quality of Simplified Polygonal Meshes: Evaluation Using Observer Studies", Proc. Ibero-American Symposium on Computer Graphics (SIACG06), pp. 169--178, Santiago de Compostela, July, 2006.
• Samuel Silva, Joaquim Madeira, Beatriz Sousa Santos, "PolyMeCo - A Polygonal Mesh Comparison Tool", Proc. 9th International Conference on Information Visualization (IV05), pp. 842--847, London, July, 2005.
• Beatriz Sousa Santos, Samuel Silva, Carlos Ferreira, Joaquim Madeira, "Comparison of Methods for the Simplification of Mesh Models of the Lungs Using Quality Indices and an Observer Study", Proc. International Conference on Medical Information Visualization - BioMedical Visualization - (MediViz 2005), pp. 15--21, London, July, 2005.
• Samuel Silva, Beatriz Sousa Santos, Joaquim Madeira, Carlos Ferreira,"Comparing three methods for simplifying mesh models of the lungs: an observer test to assess perceived quality", Proc. SPIE 2005, Vol. 5749, Image Perception, Observer Performance, and Technology Assessment, pp. 484--495, San Diego, California, February, 2005.

Detecting Nasal Vowels in Speech Interfaces based on Surface Electromyography

by João Freitas, António Teixeira, Samuel Silva, Catarina Oliveira and Miguel Sales Dias

Summary:

Nasality is a very important characteristic of several languages, such as European Portuguese. This paper addresses the challenge of nasality detection in surface electromyography (EMG) based speech interfaces. We explore the existence of useful information about the velum movement and also assess if deeper muscles can be sensed using surface electrodes in the regions of the face and neck and the best electrode location to do so. The applied procedure uses Real-Time Magnetic Resonance Imaging (RT-MRI), collected from the same speakers, providing a method to interpret EMG data.
Bellow, the datasets corresponding to the EMG signals and the velum aperture curves, extracted from RT-MRI sequences, are provided. This work is currently under consideration for publication and additional details will be provided upon request.

Datasets:

sEMG data, velum aperture curves (from RT-MRI) and aligned data

Institute of Electronics Engineering and Telematics of Aveiro (IEETA)
Campus Universitário de Santiago
3810-193 Aveiro
Email: sss {at} ua [dot] pt
Phone: +351 234 370 500