Márcio Sarroglia Pinho

Text Input Techniques for Immersive Virtual Environments: An Empirical Comparison:

Symbolic input, including text and numeric input, can be an important user task in applications of virtual environments (VEs). However, very little research has been performed to support this task in immersive VEs. This paper presents the results of an empirical evaluation of four text input techniques for immersive VEs. The techniques include the Pinch Keyboard (a typing emulation technique using pinch gloves), a one-hand chord keyboard, a soft keyboard using a pen & tablet, and speech. The experiment measured both task performance and usability characteristics of the four techniques. Results indicate that the speech technique is the fastest, while the pen & tablet keyboard produces the fewest errors. However, no single technique exhibited high levels of performance, usability and user satisfaction.

Automated methods for hippocampus segmentation: the evolution and a review of the state of the art.

The segmentation of the hippocampus in Magnetic Resonance Imaging (MRI) has been an important procedure to diagnose and monitor several clinical situations. The precise delineation of the borders of this brain structure makes it possible to obtain a measure of the volume and estimate its shape, which can be used to diagnose some diseases, such as Alzheimer’s disease, schizophrenia and epilepsy. As the manual segmentation procedure in three-dimensional images is highly time consuming and the reproducibility is low, automated methods introduce substantial gains. On the other hand, the implementation of those methods is a challenge because of the low contrast of this structure in relation to the neighboring areas of the brain. Within this context, this research presents a review of the evolution of automatized methods for the segmentation of the hippocampus in MRI. Many proposed methods for segmentation of the hippocampus have been published in leading journals in the medical image processing area. This paper describes these methods presenting the techniques used and quantitatively comparing the methods based on Dice Similarity Coefficient. Finally, we present an evaluation of those methods considering the degree of user intervention, computational cost, segmentation accuracy and feasibility of application in a clinical routine.

Virtual-SAP: an immersive tool for visualizing the response of building structures to environmental conditions

Immersive virtual environments (VEs) offer interactive, real-time visualization capabilities for engineers, architects, and scientists. This paper presents Virtual-SAP, an immersive VE application allowing users to assess building structures and their response to various environmental conditions through an interactive design-build-test-redesign cycle. Virtual-SAP has three distinct user interfaces that support its use with a high-end, multi-tracker VE system, with a low-cost portable VE system, or on the desktop. Two of these interfaces have been proven highly usable in user testing, and the third will be tested soon. Virtual-SAP is being used for both research and education.

A methodology to specify three-dimensional interaction using Petri Nets

This work presents a methodology to formally model and to build three-dimensional interaction tasks in virtual environments using three different tools: Petri Nets, the Interaction Technique Decomposition taxonomy, and Object-Oriented techniques. User operations in the virtual environment are represented as Petri Net nodes; these nodes, when linked, represent the interaction process stages. In our methodology, places represent all the states an application can reach, transitions define the conditions to start an action, and tokens embody the data manipulated by the application. As a result of this modeling process we automatically generate the core of the applications source code. We also use a Petri Net execution library to run the application code. In order to facilitate the application modeling, we have adapted Dia, a well-known graphical diagram editor, to support Petri Nets creation and code generation. The integration of these approaches results in a modular application, based on Petri Nets formalism that allows for the specification of an interaction task and for the reuse of developed blocks in new virtual environment projects.

Augmented reality environment for life support training

The area of Medical Qualification in Life Support training is being constantly improved. However, many problems still have to be faced in the training sessions. During these sessions the students or physicians can repetitively practice patient care procedures in simulated scenarios using anatomical manikins, especially designed for this type of training. Current manikins have several resources incorporated to allow and facilitate qualified training, such as pulse, arrhythmia and auscultation simulator. However, some deficiencies have been detected in the existing LS training structure. For example: automatic feedback to the students in consequence of their actions on the manikin, images like facial expressions and body injuries, and their combination with sounds that represent the clinical state of the patient. The main goal of the ARLIST project is to qualify the traditional training environment currently used for LS training, introducing image and sound resources into the training manikins. Thought these features we can simulate some aspects such as facial expressions, skin color changes and scratches and skin injuries through image projection over the manikin body, and also play sounds like cries of pain or groans of an injured man.

Collaborative hybrid virtual environment

Supposing that, in a system operated by two users in different positions, it is easier for one of them to perform some operations, we developed a 3D User Interface (3DUI) that allows two users to interact together with an object, using the three modification operations (scale, rotate and translate) to reach a goal. The operations can be performed using two augmented reality cubes, which can obtain up to 6 degrees of freedom, and every user can select any operation by using a button on the keyboard to cycle through them. To the cubes are assigned two different points of view: an exocentric view, where the user will stand at a given distance from the object, with a point of view similar to the one of a human being; and an egocentric view, where the user will stand much closer to the object, having the point of view from the objects perspective. These points of view are locked to each user, which means that one user cannot use both views, just the one assigned to his ID. The cameras have a small margin of movement, allowing just a tilt to the sides, according to the Oculuss movements. With these features, this 3DUI aims to test which point of view is better for each operation, and how the degrees of freedom should be separated between the users.

Experiences using Augmented Reality Environment for training and evaluating medical students

The process of medical training and evaluation in Brazil has been supported by several resources in order to graduate more qualified students. These resources include atlas, photos, movies, cadavers, animations, real patients, standarized patients(actors) and anatomical manikins, among others. For the reality of medical schools in a developing country as Brazil, high-end manikins are too expensive. This paper describes the validation of the Augmented Reality Environment for Life Support Training (ARLIST) system, built on the top of conventional manikins, used in cloth shops, during three editions of the Selection Exam for the Medical Residence Program of São Lucas Hospital, reaching a total of 450 users of this system. The use of manikins in these exams has showed that there is great potential for using this kind of technology in this process in medical schools, since the results were promising and resources as cadavers and experimental animals are increasingly scarce.

Identifying relationships between physiological measures and evaluation metrics for 3D interaction techniques

This project aims to present a methodology to study the relationships between physiological measures and evaluation metrics for 3D interaction techniques using methods for multivariate data analysis. Physiological responses, such as heart rate and skin conductance, offer objective data about the user stress during interaction. This could be useful, for instance, to evaluate qualitative aspects of interaction techniques without relying on solely subjective data. Moreover, these data could contribute to improve task performance analysis by measuring different responses to 3D interaction techniques. With this in mind, we propose a methodology that defines a testing protocol, a normalization procedure and statistical techniques, considering the use of physiological measures during the evaluation process. A case study comparison between two 3D interaction techniques (ray-casting and HOMER) shows promising results, pointing to heart rate variability, as measured by the NN50 parameter, as a potential index of task performance. Further studies are needed in order to establish guidelines for evaluation processes based on welldefined associations between human behaviors and human actions realized in 3D user interfaces.

Uma Revisão Sistemática de Simuladores de Endodontia Equipados com Dispositivos Hápticos

A educacao a distancia tem ganhado significativa atencao tanto na academia quanto nas iniciativas governamentais. Neste contexto, cresce tambem a preocupacao com a avaliacao da qualidade dos diversos aspectos destes cursos mediados pelas tecnologias da informacao e comunicacao. Apesar de muitos trabalhos discutirem diversos aspectos da avaliacao em Ead, a literatura carece de relatos de experiencia que, especialmente, abordem os cursos tecnicos a distancia que possuem especificidades relevantes. Assim, este trabalho relata uma experiencia onde se avalia e adapta uma das propostas existentes na literatura de avaliacao mediada por foruns, ao contexto dos cursos tecnicos a distancia, constituindo-se esta adaptacao e sua discussao as principais contribuicoes do mesmo.Em Educacao a Distância mediada por meio de Ambientes Virtuais de Aprendizagem, foruns de discussao sao um instrumento importante e amplamente utilizado na articulacao de debates e discussoes entre os atores envolvidos no processo de ensino e aprendizagem. Com a ampla utilizacao dos foruns muitas mensagens sao trocadas e isso, por vezes, excede a capacidade de monitoramento por parte dos professores e tutores. O presente trabalho apresenta a concepcao de um classificador de mensagens de foruns que classifica as mensagens em positivas ou negativas, a fim de identificar mensagens que necessitam de maior atencao. Este trabalho aplica conceitos de mineracao de textos, com o algoritmo SVM obtendo taxas de acerto satisfatorias.Este artigo apresenta o framework Contagious, cujo proposito e estabelecer diretrizes que norteiem a construcao de redes sociais online orientadas a Difusao de Inovacoes. Compreendo-se o fenomeno das redes sociais online como consequencia natural do carater social do ser humano, vislumbrou-se esse meio tecnologico de comunicacao e interacao social como potencial ferramenta para a extensao de praticas educativas, com vistas a formacao do carater integral do cidadao. Para isso, foi adotada a teoria de Difusao de Inovacoes, propria das ciencias sociais. As contribuicoes deste trabalho, portanto, compreendem duas vertentes: a) o mapeamento de principios de uma teoria social na forma de recursos computacionais e; b) um enfoque orientado a educacao sobre as redes sociais online.A proposta do trabalho consiste em desenvolver um sistema para ser usado no celular como ferramenta de auxilio para alfabetizacao, utilizando-se de imagens e sons como forma de facilitar o aprendizado. Como metodo de desenvolvimento utiliza-se o processo P@PSEduc (Processo Agil para Software Educativo) e a ferramenta JME (Java Micro Edition).O crescente uso e difusao de tecnologias Web, a ubiquidade de ferramentas educacionais vem proporcionado verdadeiras revolucoes nos ambientes de ensino. Atualmente, sabe-se que nao mais se deve tratar alunos de forma homogenea, como se assim os fossem. Em face disso, este artigo apresenta um sistema adaptativo de apoio a aprendizagem colaborativa, cujo tema e a construcao e representacao do conhecimento por meio de mapas mentais multimidia. Tal sistema, baseia-se na Teoria da Carga Cognitiva, cuja preocupacao primaria e a facilidade com a qual as informacoes sao processadas pelos individuos.

IM:MR - A tool for integration of data from different formats

The tool IM:MR is a system for integration of data originating from Intelligent Maintenance (IM) and Mixed Reality(MR) systems. The motivation for the development of this solution is to facilitate the predictive data visualization in order to contribute with the downtime reduction in critical equipments of the industry. Through of IM:MR tool use, the operator can be guided during maintenance task. In this sense are integrated CAD data, virtual components (MR data) and several signs from IM systems. This study presents an introduction, contextualization and related works supplying subsidies to the understanding of this proposal. Finally, the tool, the experiments, conclusions and future perspectives are presented.