Pen-based interfaces utilize sketch recognition so users can create and interact with complex, graphical systems via drawn input. In order for people to freely draw within these systems, users' drawing styles should not be constrained. The low-level techniques involved with sketch recognition must then be perfected, because poor low-level accuracy can impair a user's interaction experience. Corner finding, also known as stroke segmentation, is one of the first steps to free-form sketch recognition. Corner finding breaks a drawn stroke into a set of primitive symbols such as lines, arcs, and circles, so that the original stoke data can be transformed into a more machine-friendly format. By working with sketched primitives, drawn objects can then be described in a visual language, noting what primitive shapes have been drawn and the shapes? geometric relationships to each other. We present three new corner finding techniques that improve segmentation accuracy. Our first technique, MergeCF, is a multi-primitive segmenter that splits drawn strokes into primitive lines and arcs. MergeCF eliminates extraneous primitives by merging them with their neighboring segments. Our second technique, ShortStraw, works with polyline-only data. Polyline segments are important since many domains use simple polyline symbols formed with squares, triangles, and arrows. Our ShortStraw algorithm is simple to implement, yet more powerful than previous polyline work in the corner finding literature. Lastly, we demonstrate how a combination technique can be used to pull the best corner finding results from multiple segmentation algorithms. This combination segmenter utilizes the best corners found from other segmentation techniques, eliminating many false negatives (missed primitive segmentations) from the final, low-level results. We will present the implementation and results from our new segmentation techniques, showing how they perform better than related work in the corner finding field. We will also discuss limitations of each technique, how we have sought to overcome those limitations, and where we believe the sketch recognition subfield of corner finding is headed.

Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed Oct. 10, 2007). PDF text: vii, 294 p. UMI publication number: AAT 3259073. Includes bibliographical references. Also available in microfilm and microfiche formats.

Pen-based interactions are becoming widely popular on a variety of devices, including tabletPCs, mobile devices and tabletop systems. The digital pens and tablets have evolved considerably and served users in creative industries. A digital pen can sense various auxiliary inputs, such as tilt, pressure and roll. Researchers have explored properties of each channel in isolation of another. Since the human wrist and fingers can operate multiple input channels simultaneously, a natural progression warrants examination of controllability when these channels are operated simultaneously. In this thesis, I explore a class of interaction techniques, a-coord input, which requires users to control two auxiliary channels simultaneously. Through experiments, I explore the design space of a-coord input and investigate the effect of changing the order in which the channels are combined. Furthermore, I investigate its effectiveness for discrete and continuous selection tasks. Finally, this thesis shows the value of a-coord input through several applications.

Pen-based interactions are becoming widely popular on a variety of devices, including tabletPCs, mobile devices and tabletop systems. The digital pens and tablets have evolved considerably and served users in creative industries. A digital pen can sense various auxiliary inputs, such as tilt, pressure and roll. Researchers have explored properties of each channel in isolation of another. Since the human wrist and fingers can operate multiple input channels simultaneously, a natural progression warrants examination of controllability when these channels are operated simultaneously. In this thesis, I explore a class of interaction techniques, a-coord input, which requires users to control two auxiliary channels simultaneously. Through experiments, I explore the design space of a-coord input and investigate the effect of changing the order in which the channels are combined. Furthermore, I investigate its effectiveness for discrete and continuous selection tasks. Finally, this thesis shows the value of a-coord input through several applications.

Thesis (Ph. D.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 101-115). Also available in print.

Visualization of three-dimensional vector operations can be very helpful in understanding vector mathematics. However, creating these visualizations using traditional WIMP interfaces can be a troublesome exercise. In this thesis, we present VectorPad, a pen-based application for three-dimensional vector mathematics visualization. VectorPad allows users to define vectors and perform mathematical operations upon them through the recognition of handwritten mathematics. The VectorPad user interface consists of a sketching area, where the user can write vector definitions and other mathematics, and a 3D graph for visualization. After recognition, vectors are visualized dynamically on the graph, which can be manipulated by the user. A variety of mathematical operations can be performed, such as addition, subtraction, scalar multiplication, and cross product. Animations show how operations work on the vectors. We also performed a short, informal user study evaluating the user interface and visualizations of VectorPad. VectorPad's visualizations were generally well liked; results from the study show a need to provide a more comprehensive set of visualization tools as well as refinement to some of the animations.

published_or_final_version / Computer Science / Doctoral / Doctor of Philosophy

Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Title from first page of PDF file (viewed March 8, 2010). Available via ProQuest Digital Dissertations. Includes bibliographical references (p. 141-147).

Orientador: Rodolfo Jardim de Azevedo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-16T23:19:55Z (GMT). No. of bitstreams: 1 Almeida_PedroHenriqueBorgesde_M.pdf: 31023421 bytes, checksum: 6a29b56f1ac5f9218da2c948d203cfa4 (MD5) Previous issue date: 2010 / Resumo: A introdução de dispositivos computacionais no âmbito educacional não consiste apenas da inserção de hardware e software na sala de aula. Para que se obtenham resultados positivos, é necessário identificar as expectativas dos envolvidos procurando adequá-las _as práticas de ensino. Nesse aspecto, acredita-se que muito se tem a ganhar com a introdução de dispositivos computacionais no ensino, mas que é necessária uma avaliação do impacto nos alunos para identificar se essas práticas resultam numa melhor experiência de aprendizado, ainda mais que as expectativas podem variar muito em função do tópico e alunos em questão. Os principais dispositivos de entrada dos computadores, mouse e teclado, foram projetados tendo-se a produtividade em mente, limitando assim o escopo de seu uso no ensino, principalmente em aulas que requeiram o desenho de símbolos, fórmulas e diagramas. É justamente daí que surge a importância de dispositivos como o Tablet PC, com sua interface baseada em interação pen-based. A caneta permite o desenho de símbolos, fórmulas e esquemas de maneira mais natural e eficaz do que com dispositivos como mouse e teclado. Essa dissertação estuda a utilização de Tablet PCs na sala de aula na montagem de ambiente de ensino ativo e na gravação de vídeos das aulas. Os resultados mostram que os alunos consideram que o uso do Tablet PC melhora sua experiência de aprendizado, aumentando sua participação, acesso ao docente para esclarecimento de dúvidas e permitindo que haja uma maior integração entre o docente e os estudantes. O uso do Tablet PC torna muito fácil e barato o processo de gravação das aulas. Necessitando de poucos recursos de suporte, basta que o docente grave a tela do Tablet PC juntamente com o _áudio da aula para a produção dos vídeos. Esse tipo de material, como foi constatado, tem grande valor didático para os alunos, que o utilizam para revisar trechos das aulas em que tiveram dúvidas. Um dos empecilhos para a ampla adoção desse modelo de aula, como toda inovação, é o alto custo dos equipamentos. Talvez, com o barateamento das tecnologias de implementa ação do hardware do Tablet, esse modelo de ensino tenha grandes chances de ser adotado por diversas instituições de ensino, a exemplo do que já ocorre em algumas pioneiras em países desenvolvidos / Abstract: Introducing new computational devices in an educational environment isn't only giving hardware and software to the peers. It's needed to identify the peers' expectations and adequate them to the teaching methodology. The usage of computing in education can bring a great improvement in the students' learning experience, but it's necessary to access these methodologies to verify if they indeed result in a better learning experience, since the peers' expectations can vary given different subjects and students. The main input devices used in computers nowdays, mice and keyboard, were projected towards productivity. The usage of these devices in classroom activities, especially those that includes diagram, formulas and symbols drawing are limited. Thus, the importance of pen-based interface devices like the Tablet PC. The pen, different from mice and keyboard, allow students to draw simbols, formulas and schemes in a more natural way than with these devices. This thesis studies the Tablet PC usage in active learning environments and in the recording of screencasts. The results show that students found that the Tablet PC usage in these cenarios enhances the students' learning experience, rasing their participation, access to the teacher for clearing doubts and supporting a better integration between students and instructors. Tablet PC makes the lecture recording very easy and cheap. By recording only the Tablet PC screen its possible to avoid the necessity of a large recording crew. This videos, as the research concluded, have great value for the students, whom use it for review parts of the recorded lectures. The biggest challenge for the ample adoption of this lecture methodology, as any inovation, is the equipment high cost. As soon as the technology price drops, this lecture methodology has high chances of being adopted by several Universities, as it already is in some pioneers institutions in developed countries / Mestrado / Informática na Educação / Mestre em Ciência da Computação

Orientadores: Heloisa Vieira da Rocha, Rodolfo Jardim de Azevedo / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Computação / Made available in DSpace on 2018-08-13T14:21:18Z (GMT). No. of bitstreams: 1 Caceffo_RicardoEdgard_M.pdf: 24459914 bytes, checksum: 3bfe5d83970dacd1316583951e707c57 (MD5) Previous issue date: 2009 / Resumo: Atualmente existe uma tendência cada vez maior para a inclusão de dispositivos computacionais em sala de aula, disponibilizados com o intuito de melhorar o aprendizado e as práticas de ensino. Entretanto, o uso desses dispositivos não deve ser feito de forma indiscriminada, devendo ser, ao contrário, fundamentado em práticas e modelos educacionais previamente elaborados e validados. Um desses modelos é o denominado aprendizado ativo, construtivista por natureza, cujo objetivo é permitir aos estudantes terem um papel ativo em seu próprio processo de aprendizado. O modelo prevê a construção de um ambiente em que haja uma maior interação dos alunos tanto com colegas como com o professor, por meio de atividades e dinâmicas que estimulem esse tipo de comportamento. Neste contexto, a tecnologia pode ter um papel fundamental como facilitadora e em alguns caso viabilizadora dessas características de interação. Por exemplo a caneta eletrônica, presente em dispositivos móveis como o Tablet PC, possibilita o registro natural do processo de desenvolvimento do pensamento e raciocínio, com a vantagem de permitir o uso conjunto de ferramentas que possibilitem um rápido e fácil arquivamento, distribuição, análise e comparação do material por ela registrado. Nesse contexto, essa dissertação apresenta uma proposta de desenvolvimento de uma ferramenta educacional, baseada no uso de dispositivos móveis com caneta eletrônica, com o intuito de permitir a construção de um ambiente educacional colaborativo, fundamentado no modelo do aprendizado ativo. Foi elaborado e implementado um protótipo da ferramenta, validado por experimentos realizados com o para medir a interação dos alunos e do professor, além da integração do material dos alunos em sala de aula e sua posterior análise, organização e exibição feitas pelo professor. Além disso, foi possível validar a interface proposta, as necessidades e características especiais do uso da caneta eletrônica em dispositivos móveis, no caso o Tablet PC. Os resultados obtidos permitiram identificar os benefícios e vantagens que a aplicação de ferramentas interativas podem ter em sala de aula, como o aumento da participação e interesse dos alunos e a capacidade do professor poder, em tempo real, ter o retorno de cada um dos alunos sobre o conteúdo e conceitos apresentados durante a aula. / Abstract: Nowadays there is a tendency in the insertion of computing devices in the classroom, which are supposed to enhance the learning and the teaching practices. However, the use of these devices must not be done randomly, instead it must be supported by practices and valid educational models. One of these models is Active Learning, based on constructivism, which allows students to have an active role in their own learning process. The model stimulates the construction of an environment where exists an interaction between students and teacher, supported by activities that motivate this kind of behavior. In this context, the technology must support and allow these interaction characteristics. For example, the electronic pen, present in mobile devices like Tablet PCs, enable to record naturally of the development process of thinking and reasoning, also allowing the use of tools for quick and easy storage, sharing and comparing of the recorded content. In this context, this thesis shows the development of an educational tool, supported by pen based mobile devices, that has the goal to support the creation of a collaborative educational environment, based on the Active Learning model. A prototype of the tool was developed and validated by experiments which objectives were measuring the interaction between the students and teacher, and the possibility of insertion, analysis and comparison of the student's content in the classroom. Also, it was possible to validate the prototype's interface, the needs and usability characteristics of the electronic pen in mobile devices, especially Tablet PCs. The results show the benefits and vantages that the use of such interactive tools have in the classroom, like the increase of participation and concern of the students and the teacher's possibility to receive, in real time, the students feedback about the content and concepts they learned during the class. / Mestrado / Mestre em Ciência da Computação