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Pierre Boulanger

    Pierre Boulanger

    • Dr Boulanger cumulates more than 40 years of experience in 3D computer vision, rapid product development, and the ap... more
      (Dr Boulanger cumulates more than 40 years of experience in 3D computer vision, rapid product development, and the applications of virtual reality systems to medicine and industrial manufacturing. Dr Boulanger was a senior research officer for 18 years at the National Research Council of Canada. His primary research interest was 3D computer vision, rapid product development, and virtualised reality systems. He has a double appointment as a professor at the University of Alberta Department of Computing Science and the Department of Radiology and Diagnostic Imaging. He is currently the Director of the Advanced Human-Computer Interface Laboratory (AHCI) and the Scientific Director of the SERVIER Virtual Cardiac Centre. In 2013, Dr Boulanger was awarded the CISCO chair in healthcare solutions, a ten-year investment by CISCO Systems to develop new IT technologies for healthcare in Canada. The chair ended in March 2022, and most of the MedRoad activities will be transferred to Naiad Lab Inc, where I will continue my research work as the CTO of the company. Naiad Lab Inc is a start-up dedicated to using advanced technology solutions to enhance our clientele's health and quality of life worldwide and to commercialize the technologies developed during the CISCO chair.)
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    Biblioteca de la Universidad Complutense de Madrid, Base de datos de artículos de revistas, ...
    Personalized therapy, in which a therapeutic practice is adapted to an individual patient, leads to better health outcomes. Typically, this is accomplished by relying on a therapist's training and intuition along with feedback from a... more
    Personalized therapy, in which a therapeutic practice is adapted to an individual patient, leads to better health outcomes. Typically, this is accomplished by relying on a therapist's training and intuition along with feedback from a patient. While there exist approaches to automatically adapt therapeutic content to a patient, they rely on hand-authored, pre-defined rules, which may not generalize to all individuals. In this paper, we propose an approach to automatically adapt therapeutic content to patients based on physiological measures. We implement our approach in the context of arachnophobia exposure therapy, and rely on experience-driven procedural content generation via reinforcement learning (EDPCGRL) to generate virtual spiders to match an individual patient. In this initial implementation, and due to the ongoing pandemic, we make use of virtual or artificial humans implemented based on prior arachnophobia psychology research. Our EDPCGRL method is able to more quickly...
    Cardiovascular diseases are the leading cause of death globally, causing nearly 17.9 million deaths per year. Therefore, early detection and treatment are critical to help improve this situation. Many manufacturers have developed products... more
    Cardiovascular diseases are the leading cause of death globally, causing nearly 17.9 million deaths per year. Therefore, early detection and treatment are critical to help improve this situation. Many manufacturers have developed products to monitor patients’ heart conditions as they perform their daily activities. However, very few can diagnose complex heart anomalies beyond detecting rhythm fluctuation. This paper proposes a new method that combines a Short-Time Fourier Transform (STFT) spectrogram of the ECG signal with handcrafted features to detect heart anomalies beyond commercial product capabilities. Using the proposed Convolutional Neural Network, the algorithm can detect 16 different rhythm anomalies with an accuracy of 99.79% with 0.15% false-alarm rate and 99.74% sensitivity. Additionally, the same algorithm can also detect 13 heartbeat anomalies with 99.18% accuracy with 0.45% false-alarm rate and 98.80% sensitivity.
    This paper presents a method to evaluate a gesture carried out by a resident obstetrician by comparing it to a gesture carried out by an expert obstetrician. The studied gesture is the forceps blade placement. Resident paths were recorded... more
    This paper presents a method to evaluate a gesture carried out by a resident obstetrician by comparing it to a gesture carried out by an expert obstetrician. The studied gesture is the forceps blade placement. Resident paths were recorded on a childbirth simulator while placing forceps blades instrumented with six degrees of freedom sensors. The path is characterized by the positions and the orientations. In this paper we particularly focus on the orientations. Forceps orientations are expressed in the quaternion unit space and the curvature of quaternion path is compared by correlation to a reference defined by an expert. Residents have been trained on a simulator and their gestures are evaluated by comparing their orientation path curvatures to reference path curvatures. Quantitative results confirm the qualitative analysis, residents become more similar to the reference while training on simulator.
    Confocal laser endomicroscopy (CLE) is a non-invasive imaging modality of the gastrointestinal tract. Epithelial gaps in the small intestine of patients and rodents have been demonstrated using CLE. The goal of this study was to... more
    Confocal laser endomicroscopy (CLE) is a non-invasive imaging modality of the gastrointestinal tract. Epithelial gaps in the small intestine of patients and rodents have been demonstrated using CLE. The goal of this study was to quantitatively validate the findings of epithelial gap density observed with CLE against confocal microscopy (CM) and light microscopy. Two strains of mice (control 129 Sv/Ev and interleukin 10 knockout (IL-10(-/-))) underwent CLE of the terminal ileum. Adjacent ileal tissues were examined using CM and light microscopy. The total number of gaps and cells in the villi were manually counted from the three-dimensional reconstruction of cross-sectional CLE and CM images. The histology specimens were reviewed for epithelial gap and cell counts by a pathologist blinded to the study groups. The inter- and intra-observer variability for cell and gap counts were determined. For CLE, the gap densities (mean±s.d.) in the ileum for control and IL-10(-/-) mice were: 9.5±...
    Recent progress in real-time tracking of knee bone structures from fluoroscopic imaging using CT templates has opened the door to studying knee kinematics to improve our understanding of patellofemoral syndrome. The problem with CT... more
    Recent progress in real-time tracking of knee bone structures from fluoroscopic imaging using CT templates has opened the door to studying knee kinematics to improve our understanding of patellofemoral syndrome. The problem with CT imaging is that it exposes patients to extra ionising radiation, which adds to fluoroscopic imaging. This can be solved by segmenting bone templates from MRI instead of CT by using a deep neural network architecture called 2.5D U-Net. To train the network, we used the SKI10 database from the MICCAI challenge; it contains 100 knee MRIs with their corresponding annotated femur and tibia bones as the ground truth. Since patella tracking is essential in our application, the SKI10 database was augmented with a new label named UofA Patella. Using 70 MRIs from the database, a 2.5D U-Net was trained successfully after 75 epochs with an excellent final Dice score of 98%, which compared favourably with the best state-of-the-art algorithms. A test set of 30 MRIs wer...
    Portfolio diversification is one of the most effective ways to minimize investment risk. Individuals and fund managers aim to create a portfolio of assets that not only have high returns but are also uncorrelated. This goal can be... more
    Portfolio diversification is one of the most effective ways to minimize investment risk. Individuals and fund managers aim to create a portfolio of assets that not only have high returns but are also uncorrelated. This goal can be achieved by comparing the historical performance, fundamentals, predictions, news sentiment, and many other parameters that can affect the portfolio’s value. One of the most well-known approaches to manage/optimize portfolios is the well-known mean-variance (Markowitz) portfolio. The algorithm’s inputs are the expected returns and risks (volatility), and its output is the optimized weights for each asset in the target portfolio. Simplified unrealistic assumptions and constraints were used in its original version preventing its use in practical cases. One solution to improve its usability is by altering the parameters and constraints to match investment goals and requirements. This paper introduces PortFawn , an open-source Python library to create and back...
    This paper describes recent improvements to the Biris optical range sensor and the application of the technology for the estimation of volume with emphasis on wood volume measurement. A description of the range sensor and the algorithms... more
    This paper describes recent improvements to the Biris optical range sensor and the application of the technology for the estimation of volume with emphasis on wood volume measurement. A description of the range sensor and the algorithms used to calculate the volume from range data are given. Two techniques are presented: 1) evaluation of volume using model fit, and, 2) evaluation of volume directly from raw range data.
    We present a real-time system which allows musicians tointeract with synthetic virtual characters as they perform.Using Max/MSP to parameterize keyboard and vocal input, meaningful features (pitch, amplitude, chord information, and vocal... more
    We present a real-time system which allows musicians tointeract with synthetic virtual characters as they perform.Using Max/MSP to parameterize keyboard and vocal input, meaningful features (pitch, amplitude, chord information, and vocal timbre) are extracted from live performancein real-time. These extracted musical features are thenmapped to character behaviour in such a way that the musician's performance elicits a response from the virtual character. The system uses the ANIMUS framework to generatebelievable character expressions. Experimental results arepresented for simple characters.
    humanaquarium is a self-contained, transportable performance environment that is used to stage technology-mediated interactive performances in public spaces. Drawing upon the creative practices of busking and street performance,... more
    humanaquarium is a self-contained, transportable performance environment that is used to stage technology-mediated interactive performances in public spaces. Drawing upon the creative practices of busking and street performance, humanaquarium incorporates live musicians, real-time audiovisual content generation, and frustrated total internal reflection (FTIR) technology to facilitate participatory interaction by members of the public.
    Online bandwidth limitations and fluctuations impose a major challenge in estimating the amount of data to transmit in a given time period. Over or under estimation of bandwidth can jeopardize the visual fidelity of the transmitted data... more
    Online bandwidth limitations and fluctuations impose a major challenge in estimating the amount of data to transmit in a given time period. Over or under estimation of bandwidth can jeopardize the visual fidelity of the transmitted data and related multimedia data. We propose a Visual Quality Prediction (VQP) model which supports an adaptive fragmented texture transmission approach taking bandwidth fluctuations into consideration, and adjusts the data size (and thus quality) of the next block of texture data to be transmitted. The transmission depends on a set of predictors used to optimize an overall best effort
    : This paper describes techniques for the piecewise linear approximation of trimmed NURBS surfaces. The problem, called surface triangulation, arises from many applications in CAD and graphics. The new method generates triangular meshes... more
    : This paper describes techniques for the piecewise linear approximation of trimmed NURBS surfaces. The problem, called surface triangulation, arises from many applications in CAD and graphics. The new method generates triangular meshes that are adaptive to the local surface curvature. We use efficient data structures for the handling of trimming curves. We also generate Delaunay triangulation on the surface to improve the quality of the meshes.
    Today’s wearable medical devices are becoming popular because of their price and ease of use. Most wearable medical devices allow users to continuously collect and check their health data, such as electrocardiograms (ECG). Therefore, many... more
    Today’s wearable medical devices are becoming popular because of their price and ease of use. Most wearable medical devices allow users to continuously collect and check their health data, such as electrocardiograms (ECG). Therefore, many of these devices have been used to monitor patients with potential heart pathology as they perform their daily activities. However, one major challenge of collecting heart data using mobile ECG is baseline wander and motion artifacts created by the patient’s daily activities, resulting in false diagnoses. This paper proposes a new algorithm that automatically removes the baseline wander and suppresses most motion artifacts in mobile ECG recordings. This algorithm clearly shows a significant improvement compared to the conventional noise removal method. Two signal quality metrics are used to compare a reference ECG with its noisy version: correlation coefficients and mean squared error. For both metrics, the experimental results demonstrate that the...
    En este trabajo se propone un nuevo algoritmo para identificar y llenar automaticamente los huecos en regiones asociadas con superficies suaves mediante interpoladores de funciones de base radial locales.
    Advances in computer processing power and networking over the past few years have brought a significant change to the modelling and simulation of complex phenomena. Problems that formerly could only be tackled in batch mode, with their... more
    Advances in computer processing power and networking over the past few years have brought a significant change to the modelling and simulation of complex phenomena. Problems that formerly could only be tackled in batch mode, with their results visualized after- wards, can now be monitored whilst in progress using graphical means, in certain cases it is even possible to alter parameters of the computation whilst it is running, depending on what the scientist sees in the current visual output. This ability to monitor and change parameters of the computational process at any time and from anywhere is called computational steering. By combining this capability with advanced communications tools, like the Access Grid, over high-speed network it is now possible for a group of scientists located across various conti- nents to work collaboratively on simulations allowing them to compare ideas and to share their experience. In this paper, we present such an advanced collaborative computation...
    RESUMEN La vision por computador trata con el problema de encontrar interpretaciones o descripciones significativas a partir de datos visuales y se pueden pensar tres preguntas que conduzcan a la interpretacion significativa de los... more
    RESUMEN La vision por computador trata con el problema de encontrar interpretaciones o descripciones significativas a partir de datos visuales y se pueden pensar tres preguntas que conduzcan a la interpretacion significativa de los mismos. ?Cual es la informacion relevante de la imagen? ?Como debe extraerse la informacion relevante de los datos censados? ?Que medidas o caracteristicas pueden obtenerse de la informacion extraida? Este trabajo pretende responder a la segunda pregunta, asi como de identificar desde la imagen que objetos estan en el mundo y donde estan en el. Se recurre a la representacion en el espacio de escala para el analisis de los datos en diferentes niveles de la imagen y se propone una metodologia de segmentacion basada en la relacion de cada uno de los pixeles con su vecindario. Los espacios de escala son reducciones sucesivas de caracteristicas de la imagen que permiten identificar las propiedades mas significativas de la misma, aplicando un filtro Gaussiano c...
    This manuscript investigates the minimum perception thresholds for force and vibration stimuli in a simple movement pattern and using the same haptic device. The model was model derived from the well-known Up-Down Transformed Response... more
    This manuscript investigates the minimum perception thresholds for force and vibration stimuli in a simple movement pattern and using the same haptic device. The model was model derived from the well-known Up-Down Transformed Response Rule varying the force magnitude and the amplitude of vibration feedback. It was demonstrated that the vibration sensitivity was around fi fteen times smaller than the force threshold. The results were compared with previous published studies for different tasks, experimental confi gurations and devices. We concluded that the type of task signifi cantly affects human detection threshold for force and vibration feedback, and should be adapted for the design of a new haptic-based skill transfer system for minimally invasive surgery (MIS) using haptic guidance.
    A simulation of a cantilever beam was carried out with the aim of comparing the performance of two mesh-free methods: element-free Galerkin and radial point interpolation methods. In this implementation, we use two different methods to... more
    A simulation of a cantilever beam was carried out with the aim of comparing the performance of two mesh-free methods: element-free Galerkin and radial point interpolation methods. In this implementation, we use two different methods to set boundary conditions. The results were compared with the analytical solution of the cantilever problem using Timoshenko formulation [20]. In the paper, we demonstrate that both numerical methods are accurate compared to the analytical solution. However, some consideration must be taken into account when applying these methods to more complex simulations that cannot be well approximated by the boundary conditions scheme.
    We present a framework that facilitates the visualization of live musical performance using virtual and augmented reality technologies. In order to create a framework suitable for developing technologically augmented artistic... more
    We present a framework that facilitates the visualization of live musical performance using virtual and augmented reality technologies. In order to create a framework suitable for developing technologically augmented artistic applications, we have defined our system in a way that is modular and incorporates intuitive development processes when possible. In this paper we present a method of musical feature extraction and provide three examples of music visualization applications that we have developed using our system. Our visualizations illustrate features in live singing and keyboard playing using responsive virtual characters, responsive video imagery, and responsive virtual spaces.
    The recent requirement for increased speed in the design and manufacturing of new products led to a rapid evolution of the technics for fast production (rapid prototyping, machining at high speed, etc.). But a significant component did... more
    The recent requirement for increased speed in the design and manufacturing of new products led to a rapid evolution of the technics for fast production (rapid prototyping, machining at high speed, etc.). But a significant component did not follow this evolution, that is the dimensional and functional checking process, which is most of the time carried out in a traditional way. The use of range sensor allows very significant improvement in acquisition speed but does not equal the accuracy obtained with a coordinate measuring machine. In order to obtain a quality control close to that obtained in metrology, we suggest to improve the accuracy of the depth measurements by following an acquisition strategy. We propose in this paper such a strategy to automatically produce a sensing plan for completely and precisely acquiring the geometry of a surface or of a complete piece whenever possible. The system requires the exact position and orientation of the part and its CAD model in IGES form...
    To obtain a segment image is still not possible. Typically, results obtained by computer programs show over-segmentation and not well-defined edges. Most of these difficulties are believed to be due to similarity criteria used by... more
    To obtain a segment image is still not possible. Typically, results obtained by computer programs show over-segmentation and not well-defined edges. Most of these difficulties are believed to be due to similarity criteria used by segmentation algorithms. In this paper, there is an analysis of similarity criteria most used in literature and an analysis of criteria based on Bayesian decision theory.
    We present a real-time system which allows musicians to interact with synthetic virtual characters as they perform. Using Max/MSP to parameterize keyboard and vocal input, meaningful features (pitch, amplitude, chord information, and... more
    We present a real-time system which allows musicians to interact with synthetic virtual characters as they perform. Using Max/MSP to parameterize keyboard and vocal input, meaningful features (pitch, amplitude, chord information, and vocal timbre) are extracted from live performance in real-time. These extracted musical features are then mapped to character behaviour in such a way that the musician's performance elicits a response from the virtual character. The system uses the ANIMUS framework to generate believable character expressions. Experimental results are presented for simple characters.
    Uno de los esquemas mas ampliamente usados en la industria de produccion de partes para realizar el control de calidad de las piezas producidas, consiste en hacer una comparacion de dichas piezas contra un prototipo ideal denominado... more
    Uno de los esquemas mas ampliamente usados en la industria de produccion de partes para realizar el control de calidad de las piezas producidas, consiste en hacer una comparacion de dichas piezas contra un prototipo ideal denominado modelo CAD de la pieza. Para realizar tal comparacion se adquieren datos experimentales de la superficie de la pieza y se realiza una alineacion rigida entre estos y el modelo CAD de la pieza. Aunque para los sistemas actuales las piezas a revisar se consideran rigidas, existen numerosas piezas para las cuales este proceso de alineacion no es suficiente ya que la forma de tales piezas cambia en el momento de ser ensambladas. En este articulo se presenta un nuevo metodo de alineacion no rigida basado en el uso de las funciones de base radial que permite mejorar el proceso de inspeccion de piezas deformables basado en modelos CAD. Se presentan resultados de la aplicacion del metodo sobre varios modelos deformables.
    In multimedia applications, it is essential to distribute resources efficiently among different types of data in order to optimize overall quality. We propose a perceptual metric using Just-Noticeable-Difference (JND) to identify... more
    In multimedia applications, it is essential to distribute resources efficiently among different types of data in order to optimize overall quality. We propose a perceptual metric using Just-Noticeable-Difference (JND) to identify redundant mesh data so that available bandwidth can be allocated to improve texture resolution. Evaluation of perceptual impact during runtime is based on statistics in a lookup table generated during preprocessing. If the impact is less than the JND, no mesh refinement is performed. We apply Weber’s fraction to compute the JND threshold, which is verified by perceptual evaluations. Experimental result shows that our JND model can accurately predict perceptual impact based on the human visual system.
    Exercise-based cardiac rehabilitation (exCR) is the physical activity component of a multi-disciplinary cardiac rehabilitation program and is an integral step in the care of patients with acute or chronic cardiac disease. However, most... more
    Exercise-based cardiac rehabilitation (exCR) is the physical activity component of a multi-disciplinary cardiac rehabilitation program and is an integral step in the care of patients with acute or chronic cardiac disease. However, most patients do not participate in exCR despite evidence for improved outcomes and event reduction. Emerging strategies for improving exCR and overcoming these barriers points toward the use of non-hospital solutions that are based on gaming technologies. This paper presents a novel virtual reality based remote exCR system called MedBike which allows patients to perform a controlled exercise program in the comfort of their own home using a virtual reality gaming experience while being monitored by a remote exCR clinician. The paper describes the various technical aspects of the system and its pros and cons.
    Advances in computer processing power and networking over the past few years have brought significant changes to the modeling and simulation of complex phenomena. Problems that formerly could only be tackled in batch mode, with their... more
    Advances in computer processing power and networking over the past few years have brought significant changes to the modeling and simulation of complex phenomena. Problems that formerly could only be tackled in batch mode, with their results being visualized afterwards, can now be monitored using graphical means while in progress. In certain cases, it is even possible to alter parameters of the computation while it is running, depending on what the scientist perceives in the current visual output. This ability to monitor and change parameters of the computational process at any time and from anywhere is called computational steering. Combining this capability with advanced multi-modal tools to explore the data produced by these systems are key to our approach. We present an advanced multi-modal interface where sonification and 3D visualization are used in a computational steering environment specialized to solve real-time Computational Fluid Dynamics (CFD) problems. More specificall...
    Este trabajo propone una metodologia de segmentacion de imagenes de color, basada en una umbralizacion clasica en cada uno de sus componetes RGB en el espacio de escala. Palabras clave: Segmentacion de Imagenes, espacios de Escala, Filtro... more
    Este trabajo propone una metodologia de segmentacion de imagenes de color, basada en una umbralizacion clasica en cada uno de sus componetes RGB en el espacio de escala. Palabras clave: Segmentacion de Imagenes, espacios de Escala, Filtro de Variacion Total, Logica Intuicionista.
    La creacion de modelos de objetos reales es una tarea compleja para la cual se ha visto que el uso de tecnicas tradicionales de modelamiento tiene restricciones. Para resolver algunos de estos problemas, los sensores de rango basados en... more
    La creacion de modelos de objetos reales es una tarea compleja para la cual se ha visto que el uso de tecnicas tradicionales de modelamiento tiene restricciones. Para resolver algunos de estos problemas, los sensores de rango basados en laser se usan con frecuencia para muestrear la superficie de un objeto desde varios puntos de vista, lo que resulta en un conjunto de imagenes de rango que son registradas e integradas en un modelo final triangulado. En la practica, debido a las propiedades reflectivas de la superficie, las oclusiones, y limitaciones de acceso, ciertas areas de la superficie del objeto usualmente no son muestreadas, dejando huecos que pueden crear efectos indeseables en el modelo integrado. En este trabajo, presentamos un nuevo algoritmo para el llenado de huecos a partir de modelos triangulados. El algoritmo comienza localizando la frontera de las regiones donde estan los huecos. Un hueco consiste de un camino cerrado de bordes de los triangulos en la frontera que t...
    The recent requirement for increased speed in the design and manufacturing of new products led to a rapid evolution of the technics for fast production (rapid prototyping, machining at high speed, etc.). But a significant component did... more
    The recent requirement for increased speed in the design and manufacturing of new products led to a rapid evolution of the technics for fast production (rapid prototyping, machining at high speed, etc.). But a significant component did not follow this evolution, that is the dimensional and functional checking process. To automate this significant phase of production, it is necessary to develop some new analysis method. We presented an inspection method designed around three modules: a first one registrates the CAD model of a part and its 3D data obtained with an active optical range sensor, the second module segments the homogeneous cloud of 3D points in areas representing each surface of the object, and the third one is a visual check of the dimensions of the part. RÉSUMÉ.La nécessité récente d’augmenter la vitesse de conception et de réalisation de nouveaux produits a permis de développer de nouvelles techniques de production rapide (prototypage rapide, usinage à très grande vites...
    a low-cost alternative to evaluate its performance. This paper presents and discusses a method for the numerical evaluation of a given shape and its possible optimization regarding its aerodynamic performance. The computational domain is... more
    a low-cost alternative to evaluate its performance. This paper presents and discusses a method for the numerical evaluation of a given shape and its possible optimization regarding its aerodynamic performance. The computational domain is obtained by means of a b-spline curve shape parametrization, the control points are described in an input le and 2D geometry is constructed with a 2D mesher. A valid CFD domain is obtained from constructing a 3D geometry from the 2D information, additional parameters and a volumetric mesher. The aerodynamic information is obtained by solving the Navier-Stokes equations using the OpenFOAM (Opensource Field Operation And Manipulation) toolkit. The method is particularly useful to narrow a design search space for an aerodynamic shape, in which case the proof of concept that this paper presents is an airfoil. This model could be used for initial approximations to improve aerodynamic behavior of a given shape. CFD simulation could deliver accurate predic...

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