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An Inertial-Optical Tracking System for Quantitative, Freehand, 3D UltrasoundGoldsmith, Abraham Myron 16 January 2009 (has links)
Three dimensional (3D) ultrasound has become an increasingly popular medical imaging tool over the last decade. It offers significant advantages over Two Dimensional (2D) ultrasound, such as improved accuracy, the ability to display image planes that are physically impossible with 2D ultrasound, and reduced dependence on the skill of the sonographer. Among 3D medical imaging techniques, ultrasound is the only one portable enough to be used by first responders, on the battlefield, and in rural areas. There are three basic methods of acquiring 3D ultrasound images. In the first method, a 2D array transducer is used to capture a 3D volume directly, using electronic beam steering. This method is mainly used for echocardiography. In the second method, a linear array transducer is mechanically actuated, giving a slower and less expensive alternative to the 2D array. The third method uses a linear array transducer that is moved by hand. This method is known as freehand 3D ultrasound. Whether using a 2D array or a mechanically actuated linear array transducer, the position and orientation of each image is known ahead of time. This is not the case for freehand scanning. To reconstruct a 3D volume from a series of 2D ultrasound images, assumptions must be made about the position and orientation of each image, or a mechanism for detecting the position and orientation of each image must be employed. The most widely used method for freehand 3D imaging relies on the assumption that the probe moves along a straight path with constant orientation and speed. This method requires considerable skill on the part of the sonographer. Another technique uses features within the images themselves to form an estimate of each image's relative location. However, these techniques are not well accepted for diagnostic use because they are not always reliable. The final method for acquiring position and orientation information is to use a six Degree-of-Freedom (6 DoF) tracking system. Commercially available 6 DoF tracking systems use magnetic fields, ultrasonic ranging, or optical tracking to measure the position and orientation of a target. Although accurate, all of these systems have fundamental limitations in that they are relatively expensive and they all require sensors or transmitters to be placed in fixed locations to provide a fixed frame of reference. The goal of the work presented here is to create a probe tracking system for freehand 3D ultrasound that does not rely on any fixed frame of reference. This system tracks the ultrasound probe using only sensors integrated into the probe itself. The advantages of such a system are that it requires no setup before it can be used, it is more portable because no extra equipment is required, it is immune from environmental interference, and it is less expensive than external tracking systems. An ideal tracking system for freehand 3D ultrasound would track in all 6 DoF. However, current sensor technology limits this system to five. Linear transducer motion along the skin surface is tracked optically and transducer orientation is tracked using MEMS gyroscopes. An optical tracking system was developed around an optical mouse sensor to provide linear position information by tracking the skin surface. Two versions were evaluated. One included an optical fiber bundle and the other did not. The purpose of the optical fiber is to allow the system to integrate more easily into existing probes by allowing the sensor and electronics to be mounted away from the scanning end of the probe. Each version was optimized to track features on the skin surface while providing adequate Depth Of Field (DOF) to accept variation in the height of the skin surface. Orientation information is acquired using a 3 axis MEMS gyroscope. The sensor was thoroughly characterized to quantify performance in terms of accuracy and drift. This data provided a basis for estimating the achievable 3D reconstruction accuracy of the complete system. Electrical and mechanical components were designed to attach the sensor to the ultrasound probe in such a way as to simulate its being embedded in the probe itself. An embedded system was developed to perform the processing necessary to translate the sensor data into probe position and orientation estimates in real time. The system utilizes a Microblaze soft core microprocessor and a set of peripheral devices implemented in a Xilinx Spartan 3E field programmable gate array. The Xilinx Microkernel real time operating system performs essential system management tasks and provides a stable software platform for implementation of the inertial tracking algorithm. Stradwin 3D ultrasound software was used to provide a user interface and perform the actual 3D volume reconstruction. Stradwin retrieves 2D ultrasound images from the Terason t3000 portable ultrasound system and communicates with the tracking system to gather position and orientation data. The 3D reconstruction is generated and displayed on the screen of the PC in real time. Stradwin also provides essential system features such as storage and retrieval of data, 3D data interaction, reslicing, manual 3D segmentation, and volume calculation for segmented regions. The 3D reconstruction performance of the system was evaluated by freehand scanning a cylindrical inclusion in a CIRS model 044 ultrasound phantom. Five different motion profiles were used and each profile was repeated 10 times. This entire test regimen was performed twice, once with the optical tracking system using the optical fiber bundle, and once with the optical tracking system without the optical fiber bundle. 3D reconstructions were performed with and without the position and orientation data to provide a basis for comparison. Volume error and surface error were used as the performance metrics. Volume error ranged from 1.3% to 5.3% with tracking information versus 15.6% to 21.9% without for the version of the system without the optical fiber bundle. Volume error ranged from 3.7% to 7.6% with tracking information versus 8.7% to 13.7% without for the version of the system with the optical fiber bundle. Surface error ranged from 0.319 mm RMS to 0.462 mm RMS with tracking information versus 0.678 mm RMS to 1.261 mm RMS without for the version of the system without the optical fiber bundle. Surface error ranged from 0.326 mm RMS to 0.774 mm RMS with tracking information versus 0.538 mm RMS to 1.657 mm RMS without for the version of the system with the optical fiber bundle. The prototype tracking system successfully demonstrated that accurate 3D ultrasound volumes can be generated from 2D freehand data using only sensors integrated into the ultrasound probe. One serious shortcoming of this system is that it only tracks 5 of the 6 degrees of freedom required to perform complete 3D reconstructions. The optical system provides information about linear movement but because it tracks a surface, it cannot measure vertical displacement. Overcoming this limitation is the most obvious candidate for future research using this system. The overall tracking platform, meaning the embedded tracking computer and the PC software, developed and integrated in this work, is ready to take advantage of vertical displacement data, should a method be developed for sensing it.
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Feature Point Detection and Curve Approximation for Early Processing of Freehand SketchesSezgin, Tevfik Metin 01 May 2001 (has links)
Freehand sketching is both a natural and crucial part of design, yet is unsupported by current design automation software. We are working to combine the flexibility and ease of use of paper and pencil with the processing power of a computer to produce a design environment that feels as natural as paper, yet is considerably smarter. One of the most basic steps in accomplishing this is converting the original digitized pen strokes in the sketch into the intended geometric objects using feature point detection and approximation. We demonstrate how multiple sources of information can be combined for feature detection in strokes and apply this technique using two approaches to signal processing, one using simple average based thresholding and a second using scale space.
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A Framework of Freehand Gesture Interaction: Techniques, Guidelines, and ApplicationsNi, Tao 17 November 2011 (has links)
Freehand gestures have long been considered to potentially deliver natural, intuitive, terse but powerful human-computer interaction techniques. Over years, researchers have been attempting to employ freehand gestures as an alternative input modality to the conventional devices (e.g. keyboard and mouse) in a wide array of application domains, and a huge number of gesture recognition systems and gesture-based interaction techniques have been created in lab. However, a fundamental question remains: is it possible to establish an interaction framework so that we may approach freehand gestural interaction from a systematic perspective, and design coherent and consistent freehand gesture-based human-computer interaction experience? Existing research tends to focus on the technologies that enable the gestural interaction, or on the novel design of gestural interaction techniques for specific tasks and applications. Such "point designs" are claimed to be insufficient, and an existing application-specific design lends very limited insights and guidance to design problems in another application. An interaction framework allows us to move from individual designs to a more holistic approach.
The goal of this research is to construct a framework to support a systematic approach for designing freehand gesture-based interactions. Toward this goal our research began with a review and examination of the gesture interaction literature, followed by an analysis of the essential components of an interaction framework. We then proposed and justified the scope of research and the approach we took to construct the interaction framework. We have designed and evaluated (analytically and empirically) gestural interaction techniques for two broad categories of freehand gestures we specified — spatial gestures, and surface gestures. In the design activity, we have discovered and proposed the core design principles and guidelines, and validated them via user studies. Finally, we assessed the ability of the freehand gesture interaction framework we have constructed to help designers create new applications and designs, by putting together a few proof-of-concept examples of a coherent and consistent freehand gesture user interface. / Ph. D.
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Suporte analógico: desenho à mão livreRossi, Maria Cristina de Barros 11 March 2008 (has links)
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Previous issue date: 2008-03-11 / Instituto Presbiteriano Mackenzie / It is noticeable in the circle of academics and professionals the importance of drawing as a fundamental instrument to reflect and elaborate the intention and exploration of space and form of the architect. In a great extend students will acquire line drawing experiences through drawing practice by recognizing forms in the use of representative instruments, and materializing it with the help of techniques. This reflexive thought has an active character which acts in a straight forward manner to the way thinking of the project, acting together with verbal concepts, and by this means establishing the synthesis done by configuration. It is not a matter of passively represent what is perceived or thought but yet an immediate act of thinking the project. Expression drawing, as a drawing that does not possess norms, greatly contributes to this process with its fundamental participation in the early years of the Architecture and Urbanism courses when students bring their expressive liberty and carry with themselves a lessen commitment to constructive techniques. This study intends to question the meaning in time for the drawing term by expressing its validity on the way of thinking of it nowadays. / Nos meios acadêmicos e profissionais verifica-se cotidianamente a importância do desenho enquanto instrumento fundamentalmente adequado para a reflexão e elaboração de intenções projetuais de espaços na formação de um arquiteto; em grande parte é por intermédio dele que os estudantes irão adquirir experiências no traço, no reconhecimento das formas, no uso de instrumentos de representação e, com o auxílio de algumas técnicas, materializá-los. Essa reflexão por intermédio do desenho tem caráter ativo, ou seja, atua de forma decisiva no ato de pensar o projeto, agindo conjuntamente com os conceitos verbais, estabelecendo, dessa forma, uma síntese que se faz em configuração; não se trata de representar passivamente o percebido ou o pensado , mas, sim, imediatamente um ato de pensar o projeto. O desenho de expressão, ou seja, o desenho não normatizado, contribui decisivamente para este processo, com fundamental atuação no início do curso de Arquitetura e Urbanismo quando os estudantes possuem maior liberdade expressiva e, ainda, menor compromisso com as técnicas construtivas.Este estudo pretende questionar o significado do termo desenho no tempo, os principais paradigmas de sua manifestação em culturas distintas e dissertar sobre a validade desse raciocínio nos dias de hoje.
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3D Freehand Ultrasonography in Quantifying Muscle Morphological Parameters in Lower Extremity / 3D-ultrasonografi på frihand för kvantifiering avmorfologiska muskelparametrar i nedre extremitetenHuang, Ruoyu January 2021 (has links)
Muscle morphological parameters such as fascicle length (FL), pennationangle (PA) and physiologic cross-sectional area (PCSA) can provide an insightinto the reasons of the deteriorated muscle functions caused by pathologies.This study investigates the 3D structure of the lower leg muscles using 3Dfreehand ultrasound (3DfUS). This imaging modality uses a motion capturesystem to track the position of the US probe during acquisition and thusreconstruct the structure of the tissues in 3D. In this study, two subjects werescanned on the medial gastrocnemius (MG) and tibialis anterior (TA) musclesin the lower leg using 3DfUS system. The FL and PA of the muscles werecalculated and compared with the values previously measured using diffusiontensor imaging (DTI). The results using 3DfUS were averagely 19.2% largerin FL and 2.9%larger in PA. In conclusion, 3DfUS can successfully determinemuscle morphological parameters within a physiologically acceptable range.But the differences in FL observed between the two imaging modalities werequite big, which probably was due to the differences in sample size and area.The values can also differ greatly within the 3DfUS measurements as a resultof different manipulations during data processing, and the 3DfUS protocolneeds to be further improved in future studies.
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Osvojování kresby dětmi předškolního věku (3, 4 až 5letých) / Learning to draw in preschoolers (3, 4 and 5 years old)Pejchalová, Zuzana January 2011 (has links)
Synopsis of the thesis in Englis Surname and firstname: Bc. Pejchalová Zuzana Department: psychologie PdF UK Praha Title of thesis: Osvojování kresby dětmi předškolního věku (3, 4 - 5letými) Thesis title in English: Learning to draw in preschoolers (3, 4 and 5 years old) Supervisor: PhDr. Miroslav Klusák, CSc. Number of pages: 63 Number of attachments: 30 Number of used literature: 14 Keywords: Drawing in kindergarten Graphmotor Group drawing Guided drawing Freehand drawing Summary in English Diploma thesis is focused on learning to draw in preschoolers. It describes individual art-education parts of the daily program in which children in kindergarten draw. It gives closer characteristics of what children draw within each part, as well as of the educational targets enforced by the teacher. Finally, it focuses on the individual differences in children's learning.
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Suivi des vaisseaux sanguins en temps réel à partir d’images ultrasonores mode-B et reconstruction 3D : application à la caractérisation des sténoses artériellesMerouche, Samir 03 1900 (has links)
La maladie des artères périphériques (MAP) se manifeste par une réduction (sténose) de la lumière de l’artère des membres inférieurs. Elle est causée par l’athérosclérose, une accumulation de cellules spumeuses, de graisse, de calcium et de débris cellulaires dans la paroi artérielle, généralement dans les bifurcations et les ramifications. Par ailleurs, la MAP peut être causée par d`autres facteurs associés comme l’inflammation, une malformation anatomique et dans de rares cas, au niveau des artères iliaques et fémorales, par la dysplasie fibromusculaire.
L’imagerie ultrasonore est le premier moyen de diagnostic de la MAP. La littérature clinique rapporte qu’au niveau de l’artère fémorale, l’écho-Doppler montre une sensibilité de 80 à 98 % et une spécificité de 89 à 99 % à détecter une sténose supérieure à 50 %. Cependant, l’écho-Doppler ne permet pas une cartographie de l’ensemble des artères des membres inférieurs. D’autre part, la reconstruction 3D à partir des images échographiques 2D des artères atteintes de la MAP est fortement opérateur dépendant à cause de la grande variabilité des mesures pendant l’examen par les cliniciens. Pour planifier une intervention chirurgicale, les cliniciens utilisent la tomodensitométrie (CTA), l’angiographie par résonance magnétique (MRA) et l’angiographie par soustraction numérique (DSA).
Il est vrai que ces modalités sont très performantes. La CTA montre une grande précision dans la détection et l’évaluation des sténoses supérieures à 50 % avec une sensibilité de 92 à 97 % et une spécificité entre 93 et 97 %. Par contre, elle est ionisante (rayon x) et invasive à cause du produit de contraste, qui peut causer des néphropathies. La MRA avec injection de contraste (CE MRA) est maintenant la plus utilisée. Elle offre une sensibilité de 92 à 99.5 % et une spécificité entre 64 et 99 %. Cependant, elle sous-estime les sténoses et peut aussi causer une néphropathie dans de rares cas. De plus les patients avec stents, implants métalliques ou bien claustrophobes sont exclus de ce type d`examen. La DSA est très performante mais s`avère invasive et ionisante.
Aujourd’hui, l’imagerie ultrasonore (3D US) s’est généralisée surtout en obstétrique et échocardiographie. En angiographie il est possible de calculer le volume de la plaque grâce à l’imagerie ultrasonore 3D, ce qui permet un suivi de l’évolution de la plaque athéromateuse au niveau des vaisseaux. L’imagerie intravasculaire ultrasonore (IVUS) est une technique qui mesure ce volume. Cependant, elle est invasive, dispendieuse et risquée. Des études in vivo ont montré qu’avec l’imagerie 3D-US on est capable de quantifier la plaque au niveau de la carotide et de caractériser la géométrie 3D de l'anastomose dans les artères périphériques. Par contre, ces systèmes ne fonctionnent que sur de courtes distances. Par conséquent, ils ne sont pas adaptés pour l’examen de l’artère fémorale, à cause de sa longueur et de sa forme tortueuse.
L’intérêt pour la robotique médicale date des années 70. Depuis, plusieurs robots médicaux ont été proposés pour la chirurgie, la thérapie et le diagnostic. Dans le cas du diagnostic artériel, seuls deux prototypes sont proposés, mais non commercialisés. Hippocrate est le premier robot de type maitre/esclave conçu pour des examens des petits segments d’artères (carotide). Il est composé d’un bras à 6 degrés de liberté (ddl) suspendu au-dessus du patient sur un socle rigide. À partir de ce prototype, un contrôleur automatisant les déplacements du robot par rétroaction des images échographiques a été conçu et testé sur des fantômes. Le deuxième est le robot de la Colombie Britannique conçu pour les examens à distance de la carotide. Le mouvement de la sonde est asservi par rétroaction des images US. Les travaux publiés avec les deux robots se limitent à la carotide.
Afin d’examiner un long segment d’artère, un système robotique US a été conçu dans notre laboratoire. Le système possède deux modes de fonctionnement, le mode teach/replay (voir annexe 3) et le mode commande libre par l’utilisateur. Dans ce dernier mode, l’utilisateur peut implémenter des programmes personnalisés comme ceux utilisés dans ce projet afin de contrôler les mouvements du robot.
Le but de ce projet est de démontrer les performances de ce système robotique dans des conditions proches au contexte clinique avec le mode commande libre par l’utilisateur. Deux objectifs étaient visés: (1) évaluer in vitro le suivi automatique et la reconstruction 3D en temps réel d’une artère en utilisant trois fantômes ayant des géométries réalistes. (2) évaluer in vivo la capacité de ce système d'imagerie robotique pour la cartographie 3D en temps réel d'une artère fémorale normale. Pour le premier objectif, la reconstruction 3D US a été comparée avec les fichiers CAD (computer-aided-design) des fantômes. De plus, pour le troisième fantôme, la reconstruction 3D US a été comparée avec sa reconstruction CTA, considéré comme examen de référence pour évaluer la MAP.
Cinq chapitres composent ce mémoire. Dans le premier chapitre, la MAP sera expliquée, puis dans les deuxième et troisième chapitres, l’imagerie 3D ultrasonore et la robotique médicale seront développées. Le quatrième chapitre sera consacré à la présentation d’un article intitulé " A robotic ultrasound scanner for automatic vessel tracking and three-dimensional reconstruction of B-mode images" qui résume les résultats obtenus dans ce projet de maîtrise. Une discussion générale conclura ce mémoire.
L’article intitulé " A 3D ultrasound imaging robotic system to detect and quantify lower limb arterial stenoses: in vivo feasibility " de Marie-Ange Janvier et al dans l’annexe 3, permettra également au lecteur de mieux comprendre notre système robotisé. Ma contribution dans cet article était l’acquisition des images mode B, la reconstruction 3D et l’analyse des résultats pour le patient sain. / Locating and quantifying stenosis length and severity are essential for planning adequate treatment of peripheral arterial disease (PAD). To do this, clinicians use imaging methods such as ultrasound (US), Magnetic Resonance Angiography (MRA) and Computed Tomography Angiography (CTA). However, US examination cannot provide maps of entire lower limb arteries in 3D, MRA is expensive and invasive, CTA is ionizing and also invasive. We propose a new 3D-US robotic system with B-mode images, which is non-ionizing, non-invasive, and is able to track and reconstruct in 3D the superficial femoral artery from the iliac down to the popliteal artery, in real time.
In vitro, 3D-US reconstruction was evaluated for simple and complex geometries phantoms in comparison with their computer-aided-design (CAD) file in terms of lengths, cross sectional areas and stenosis severity. In addition, for the phantom with a complex geometry, an evaluation was realized using Hausdorff distance, cross-sectional area and stenosis severity in comparison with 3D reconstruction with CTA. A mean Hausdorff distance of 0.97± 0.46 mm was found for 3D-US compared to 3D-CTA vessel representations. In vitro investigation to evaluate stenosis severity when compared with the original phantom CAD file showed that 3D-US reconstruction, with 3%-6% error, is better than 3D-CTA reconstruction, with 4-13% error. The in vivo system’s feasibility to reconstruct a normal femoral artery segment of a volunteer was also investigated.
All of these promising results show that our ultrasound robotic system is able to track automatically the vessel and reconstruct it in 3D as well as CTA. Clinically, our system will allow firstly to the radiologist to have 3D images readily interpretable and secondly, to avoid radiation and contrast agent for patients.
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Freehand Digital Drawing: a Boost to Creative Design. The Observer's Eye and the Draftsman BrainLeandri, Gaia 17 October 2022 (has links)
[ES] La representación de un proyecto arquitectónico tiene diferentes finalidades, una de las más relevantes es su visualización. El tema de esta tesis es la relación entre el diseñador, su actividad cerebral durante la fase creativa, el proyecto representado y la mente del observador. La pregunta, planteada por arquitectos, diseñadores y académicos en los años ochenta y aún abierta a soluciones estimulantes, es una pregunta bien conocida sobre si la creciente digitalización puede ser perjudicial o beneficiosa para esta relación. Después de un análisis de la imagen en la arquitectura a partir del Renacimiento, informado en la Parte 1, se revisan y discuten las técnicas actuales de representación. La primera pregunta, abordada en la Parte 2, fue si la simulación de la realidad con renderizado de calidad fotográfica garantiza una visualización mejor o peor que una imagen tradicionalmente dibujada a mano. Se elaboró un cuestionario para verificar las características de comunicación y representación de las imágenes producidas con las dos técnicas. Los resultados mostraron que estas dos cualidades estaban más presentes en el caso del dibujo a mano alzada que en los renders fotorrealistas. La Parte 3 se centró en el diseñador y utilizó las herramientas proporcionadas por la neurociencia, a saber, el EEG y las 'respuestas evocadas', para cuantificar la actividad cerebral de alguien que hace un dibujo a mano alzada con respecto a CAD. Dado que la tecnología utilizada nunca antes se había aplicado a un sujeto al realizar un diseño, la investigación se dividió en tres experimentos separados. El primero se dedicó a encontrar una forma confiable de realizar registros durante el movimiento del miembro superior en la ejecución del dibujo; los experimentos segundo y tercero tenían como objetivo el análisis específico de la actividad cerebral que precede y sigue a los movimientos individuales de los signos trazados. Los resultados mostraron que la actividad motora relacionada con el dibujo a mano alzada estuvo acompañada por un aumento en la amplitud de las respuestas electroencefalográficas en comparación con el dibujo con CAD. Este dato es probablemente un importante paso adelante a favor de la hipótesis de que la creatividad también puede mejorarse mediante el movimiento en el dibujo a mano alzada. La conclusión es que las imágenes así dibujadas crean una mejor correspondencia entre el autor y el observador, y que el movimiento y la percepción sensorial de la mano pueden fomentar la creatividad. Recientemente, los avances en la técnica de las tabletas de dibujo han proporcionado una nueva técnica para el dibujo a mano alzada, donde se combina la capacidad de gestión de datos del ordenador con los gestos naturales tradicionalmente ligados al uso del papel y el lápiz. de la tecnología moderna puede fusionar el factor humano junto con las nuevas tecnologías digitales. / [CA] La representació d'un projecte arquitectònic té diferents finalitats, una de les més rellevants és la seva visualització. El tema d'aquesta tesi és la relació entre el dissenyador, la seva activitat cerebral durant la fase creativa, el projecte representat i la ment de l'observador. La pregunta, plantejada per arquitectes, dissenyadors i estudiosos als anys vuitanta i encara oberta a solucions estimulants, és una qüestió ben coneguda si augmentar la digitalització pot ser perjudicial o beneficiós per a aquesta relació. Després d'una anàlisi de la imatge en arquitectura a partir del període renaixentista, informada a la part 1, es revisen i discuteixen les tècniques de representació actuals. La primera pregunta, abordada a la part 2, va ser si la simulació de la realitat amb renderització de qualitat fotogràfica garanteix una visualització millor o pitjor que una imatge tradicionalment dibuixada a mà. Es va elaborar un qüestionari per comprovar les característiques de comunicació i representació de les imatges produïdes amb les dues tècniques. Els resultats van mostrar que aquestes dues qualitats estaven més presents en el cas del dibuix a mà alçada que en els renders fotorealistes. La part 3 es va centrar en el dissenyador i va utilitzar les eines proporcionades per la neurociència, és a dir, l'EEG i les 'respostes evocades', per quantificar l'activitat cerebral d'algú que realitza un dibuix a mà alçada respecte al CAD. Com que la tecnologia utilitzada mai abans s'havia aplicat a un tema mentre es feia un disseny, la investigació es va dividir en tres experiments separats. El primer es va dedicar a trobar una manera fiable de fer enregistraments durant el moviment de l'extremitat superior en l'execució del dibuix; el segon i el tercer experiment estaven dirigits a l'anàlisi específica de l'activitat cerebral que precedeix i segueix els moviments individuals dels signes traçats. Els resultats van mostrar que l'activitat motora relacionada amb el dibuix a mà alçada va anar acompanyada d'un augment de l'amplitud de les respostes electroencefalogràfiques en comparació amb el dibuix amb CAD. Aquesta dada és probablement un pas endavant significatiu a favor de la hipòtesi que la creativitat també es pot millorar amb el moviment en el dibuix a mà alçada. La conclusió és que les imatges dibuixades d'aquesta manera creen una millor correspondència entre autor i observador, i que el moviment i la percepció sensorial de la mà poden fomentar la creativitat. Recentment, els avenços en la tècnica de dibuix a tauletes han aportat una nova tècnica de dibuix a mà alçada, on la capacitat de gestió de dades de l'ordinador es combina amb els gestos naturals tradicionalment vinculats a l'ús del paper i el llapis. de la tecnologia moderna pot fusionar el factor humà amb les noves tecnologies digitals. / [EN] The representation of an architectural project aims at several intents, one of the most relevant being the visualisation of a design. The subject of this dissertation is therefore the relationship between the draftsman, the creativity of his brain, the represented design, and the mind of the observer. Since the Eighties, architects, designers and scholars wondered whether the current habit of an ever increasing digitalisation could be detrimental or advantageous to such relationship. After an analysis of architectural imaging since the Renaissance, as reported in Part 1, the current techniques are reviewed and discussed. The first question, addressed in Part 2, has been whether the simulation of reality with renders of photographic quality, would relate to the observer better or worse than a traditionally hand drawn image. A questionnaire has been constructed to probe the communication and representation qualities of the images. The results suggested that these two qualities were best represented in the case of freehand drawing compared to photorealistic renders. Part 3 was focused on the designer and used the instruments provided by neuroscience, i.e. the EEG and 'evoked responses', to quantify the brain activity in connection with freehand and CAD drawing. Because the involved technology had never been applied before to a drawing subject, the investigation had to be divided into three separate experiments. The first one was dedicated to finding a reliable way to perform the recordings in subjects who freely moved their arm and hand while drawing. The second and third experiments were aimed at analysing the cerebral activity occurring before and after each drawing movement. All results demonstrated that a larger cerebral activity preceded and followed each movement in freehand drawing compared to CAD design. This finding may be considered a robust step towards the notion that also creativity may consequently be improved. The final conclusion is that the freehand drawn images make a better link between author and observer, and at the same time the very movement and haptic perception of the hand elicit creativity. Indeed, the most recent advances in technology of drawing tablets have provided a new medium for freehand drawing, which can exploit the capacity of data handling of computers with the natural movement of using pencil and paper, ending up in a traditional hand made product. A wise usage of modern technology can therefore merge the human factor with the digital world. / Leandri, G. (2022). Freehand Digital Drawing: a Boost to Creative Design. The Observer's Eye and the Draftsman Brain [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/188091 / TESIS
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An analysis of teacher competencies in a problem-centred approach to dynamic Geometry teachingNdlovu, Mdutshekelwa 11 1900 (has links)
The subject of teacher competencies or knowledge has been a key issue in mathematics
education reform. This study attempts to identify and analyze teacher competencies
necessary in the orchestration of a problem-centred approach to dynamic geometry
teaching and learning. The advent of dynamic geometry environments into classrooms
has placed new demands and expectations on mathematics teachers.
In this study the Teacher Development Experiment was used as the main method of
investigation. Twenty third-year mathematics major teachers participated in workshop
and microteaching sessions involving the use of the Geometer's Sketchpad dynamic
geometry software in the teaching and learning of the geometry of triangles and
quadrilaterals. Five intersecting categories of teacher competencies were identified:
mathematical/geometrical competencies. pedagogical competencies. computer and
software competences, language and assessment competencies. / Mathematical Sciences / M. Ed. (Mathematical Education)
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Připravenost dětí v oblasti grafomotoriky na vstup do základní školy / Level of graphomotor skills of preschool children before entering elementary schoolDousková, Eliška January 2012 (has links)
There are currently increasingly debated issues of entering the schooling, especially in the terms of levels of preparedness to enter the first grade and the school's requirements on the first- graders. This is due to a large number of often complex changes which the entrance into the first grade means for the children and their families. It is the best for the first-graders do all these changes without undue frustration, it is necessary that their physical, mental and neural development and readiness were on sufficient level. Because of extensiveness of this topic, only the part of it was selected for this thesis, as its name says: The level of graphomotor skills of preschool children before entering elementary school. The area of graphomotor skills is presented in the context of writing skills throughout this thesis. The legislative definition of compulsory school attendance and the issue of writing as an essential part of literacy is covered within the theoretical part. The topic of entry into the first grade and the school preparedness of children are explained. The area of graphomotor skills in the terms of the development, in the terms of relation to the coarse and fine motor skills, laterality and external conditions which affect graphomotor skills is covered in detail. The significance...
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