Cléber Gimenez Corrêa

Evaluation of VR medical training applications under the focus of professionals of the health area

This paper presents part of the implementation of a Virtual Reality (VR) framework, involving the building of an interaction module with support to conventional and non-conventional devices, and the evaluation of a system prototype, considering computational and human aspects. The proposal of the evaluation is to improve the framework, and consequently, the applications generated by it, following ideas and opinions of healths professionals (doctors and students), who are the target public of this project.

Virtual Reality-Based System for Training in Dental Anesthesia

This paper presents the development and preliminary evaluation of a Virtual Reality-based system for training in dental anesthesia. The development focused the simulation of an anesthesia procedure task. The evaluation involved graphic and haptic issues and had the presence of experts in the dentistry area. The assessment aimed at attributes that may influence the human-computer interaction, hindering realism, an important challenge in systems of this type. The attributes selected were: the update rate, the appearance of the virtual models and the number of viewpoints of the virtual environment, as well as the characteristics of the haptic device. Despite constraints were found, in the perception of the experts, the system may provide realism and help with the training of certain tasks.

Immersive Teleconferencing System Based on Video-Avatar for Distance Learning

Teleconference is an important means of communication in distance learning courses. Unlike other technologies used in education, the technology that enables virtual conferencing has changed little since it began to be used. Even the transition from analog to digital technology and the adoption of IP technology changed little in the communication characteristics of this media, basically the same of 2D. The project presented here is part of a new field of research, called immersive telecommunication, which aims at increasing the sense of immersion and presence of the participants. For this purpose, a videoconferencing system was developed, which allows presenters to immerse themselves in a 3D virtual environment, through their video-avatar, and be watched remotely in the form of 3D video. This system integrates several subprojects, involving the capture and rendering of a video-avatar, background removal, gesture recognition, interaction design, among others. The aim of this paper is to present the system architecture and an overview of its modules, the key challenges and adopted solutions.

Haptic Simulation for Virtual Training in Application of Dental Anesthesia

Several fields of the knowledge have been benefited by technologies from Virtual Reality (VR) area. This paper presents an analysis of problems related to the domain of dentistry, specifically for training in anesthesia, and the possibility of resolution using VR. The analysis assumes that the haptic interaction in virtual environments is relevant in the area of training in health and may contribute in the skills acquisition, providing realistic experiences to the trainess. Initially, a detailed requirements survey with the participation of experts was conducted, as well as the development of a prototype for preliminary testing.

Non-photorealistic rendering in stereoscopic 3D visualization

Spatial visualization of virtual contents appears to be, with the appearance of stereoscopic displays, the next step for increasing immersion in visual output. This kind of visualization can be used to facilitate the understanding of complex informations, like anatomic structures. One approach currently adopted for this purpose is the use of non-photorealisitic rendering (NPR), like proposed by Tietjen, Isenberg and Preim [2005]. However, this NPR style, which conventionally tries to simulate a 2D illustration, fused with the the stereoscopic 3D visualization can break the 3D perception of the virtual contents. This work aims to study the 3D perception of virtual contents represented using NPR techniques, in order to evaluate the influence of NPR in the 3D perception when used with stereoscopic information visualization. The stereoscopic NPR visualization was applied in VIDA, a system for the study of anatomic structures that enables the stereoscopic visualization and interaction with virtual objects [Tori et al. 2009], in order to proceed the user tests, the figure 1c show the system used in the test.

Haptic interaction objective evaluation in needle insertion task simulation

Formulation of perceptual objective metrics for haptic interaction evaluation is still a challenge. These metrics are created including the human perception and the distortion intensity of the haptic signals, however, they disregarded peculiarities of tasks to be performed during human-computer interaction. Thus, we proposed a metric specialized in healthcare training for haptic interaction evaluation, that considers the importance degree of the different steps of a task and distortion intensity. The novel perceptual objective metric was validated with experts from dentistry area. The task selected was needle insertion, a common task in healthcare training systems. Our metric was compared to a state of the art metric using position haptic attribute and presented more coherent results with users perception in some cases.

Three-Dimensionality Perception Evaluation in Stereoscopic Virtual Environments: A Systematic Review

The three-dimensionality perception in visual scenes is provided by the representation of objects in different dimensions and distortion, both related to perspective. However, the feeling of being in a virtual environment can be provided by the use of stereoscopic techniques. Although there are several studies on users three-dimensionality perception in stereoscopic systems, there are no systematic reviews in the literature aimed at categorizing evaluation methods about this perception in experimental studies. This article presents a systematic review that identifies effects, parameters and evaluation methods regarding the three-dimensionality perception in virtual environments with stereoscopy.

Using Genetic Algorithms in Test Data Generation: A Critical Systematic Mapping

Software testing activities account for a considerable portion of systems development cost and, for this reason, many studies have sought to automate these activities. Test data generation has a high cost reduction potential (especially for complex domain systems), since it can decrease human effort. Although several studies have been published about this subject, articles of reviews covering this topic usually focus only on specific domains. This article presents a systematic mapping aiming at providing a broad, albeit critical, overview of the literature in the topic of test data generation using genetic algorithms. The selected studies were categorized by software testing technique (structural, functional, or mutation testing) for which test data were generated and according to the most significantly adapted genetic algorithms aspects. The most used evaluation metrics and software testing techniques were identified. The results showed that genetic algorithms have been successfully applied to simple test data generation, but are rarely used to generate complex test data such as images, videos, sounds, and 3D (three-dimensional) models. From these results, we discuss some challenges and opportunities for research in this area.

Virtual Reality simulator for dental anesthesia training in the inferior alveolar nerve block

Abstract Objectives This study shows the development and validation of a dental anesthesia-training simulator, specifically for the inferior alveolar nerve block (IANB). The system developed provides the tactile sensation of inserting a real needle in a human patient, using Virtual Reality (VR) techniques and a haptic device that can provide a perceived force feedback in the needle insertion task during the anesthesia procedure. Material and Methods To simulate a realistic anesthesia procedure, a Carpule syringe was coupled to a haptic device. The Volere method was used to elicit requirements from users in the Dentistry area; Repeated Measures Two-Way ANOVA (Analysis of Variance), Tukey post-hoc test and averages for the results’ analysis. A questionnaire-based subjective evaluation method was applied to collect information about the simulator, and 26 people participated in the experiments (12 beginners, 12 at intermediate level, and 2 experts). The questionnaire included profile, preferences (number of viewpoints, texture of the objects, and haptic device handler), as well as visual (appearance, scale, and position of objects) and haptic aspects (motion space, tactile sensation, and motion reproduction). Results The visual aspect was considered appropriate and the haptic feedback must be improved, which the users can do by calibrating the virtual tissues’ resistance. The evaluation of visual aspects was influenced by the participants’ experience, according to ANOVA test (F=15.6, p=0.0002, with p<0.01). The user preferences were the simulator with two viewpoints, objects with texture based on images and the device with a syringe coupled to it. Conclusion The simulation was considered thoroughly satisfactory for the anesthesia training, considering the needle insertion task, which includes the correct insertion point and depth, as well as the perception of tissues resistances during the insertion.

Gamification as a Learning Strategy in a Simulation of Dental Anesthesia

Considering the high failure rate in the procedure of applying dental anesthesia, this paper presents the process of gamification of a simulator of this procedure. The objective of this serious game is to promote a more attractive learning strategy that encourages and at the same time evaluates training, reducing risks to patients. For this, it was conducted a literature review about serious games applications related to health care. From these examples, the elements of games that could be added to the current context were highlighted. An analysis of the simulator, describing its most relevant points was performed. Results, as well as discussion of problems, solutions and testing showed that the gamification process was successful and the game can be submitted to the experts evaluation.