Olfaction has not been explored in virtual reality environments to the same extent as the visual and auditory senses. Much less research has been done with olfactory devices, and very few of them can be easily integrated into virtual reality applications. The inclusion of odor into virtual reality simulations using a chemical device involves challenges such as possible diffusion into undesired areas, slow dissipation, the definition of various parameters (e.g., concentration, frequency, and duration), and an appropriate software solution for controlling the diffusion of the odor. This paper aims to present a non-intrusive, mobile, low cost and wearable olfactory display, and a software service that allows the developer to easily create applications that include olfactory stimuli integrated with virtual reality headset glasses. We also present a case study conducted with 32 people to evaluate their satisfaction when using the olfactory display. Our findings indicate that our solution works as expected, producing odor properly and being easy to integrate to applications. Supplementary Information: The online version contains supplementary material available at 10.1007/s00530-022-00908-8.

Software testing involves probing into the behavior of software systems to uncover faults. Most testing activities are complex and costly, so a practical strategy that has been adopted to circumvent these issues is to automate software testing. There has been a growing interest in applying machine learning (ML) to automate various software engineering activities, including testing-related ones. In this paper, we set out to review the state-of-the art of how ML has been explored to automate and streamline software testing and provide an overview of the research at the intersection of these two fields by conducting a systematic mapping study. We selected 48 primary studies. These selected studies were then categorized according to study type, testing activity, and ML algorithm employed to automate the testing activity. The results highlight the most widely used ML algorithms and identify several avenues for future research. We found that ML algorithms have been used mainly for test-case generation, refinement, and evaluation. Also, ML has been used to evaluate test oracle construction and to predict the cost of testing-related activities. The results of this paper outline the ML algorithms that are most commonly used to automate software-testing activities, helping researchers to understand the current state of research concerning ML applied to software testing. We also found that there is a need for better empirical studies examining how ML algorithms have been used to automate software-testing activities.

This paper describes a teaching approach supported by game development projects to teach the course Human-Computer Interaction. The main reason for adopting such an approach was the attempt to make the course more attractive and to reduce evasion. This approach aims for enhancing students' motivation, commitment, and proactivity during their learning process. In addition, a case study is presented in which a Math game was defined as the final artifact for each group of students. A total of 145 students took the course, and 115 were participants in this research. The results and discussions from both students' and teachers' standpoints, as well as the project itself, are presented.

Anatomy learning is very important for many courses, and it requires understanding three-dimensional (3D) shapes, most forms of anatomy teaching are offered to students through two-dimensional (2D) resources, such as images and videos. Many software solutions were developed with the purpose of assisting anatomy teaching and learning, arranging varied techniques and assets, as interaction and visualization of 3D virtual models. Despite great features, these solutions lack standards utilization and pedagogical methodology. This paper aims to present a 3D content generation technique to Moodle, one of the most popular platforms for teaching and learning management, built upon a specific pedagogical methodology, and validated by educational experts. The standard used in this technique allow sharing and reuse of content not only among Moodle systems, which are used by a large number of educational institutions and professors but also in other Virtual Learning Environments.

A process-scheduling algorithm is a fundamental operating system function that manages the assignment of CPU (Central Processing Unit) processes. It aims to make the system efficient, fast, and fair, allowing as many processes as possible to make the best use of the CPU at any given time. Understanding scheduling algorithms and their impact in practice is a challenging and time-consuming task for students, given the differing features of each operating system. Operating system simulators are usually based on either a command line or bidimensional front-end interface. This paper presents a process-scheduling simulator based on virtual reality technology that allows students to develop their empirical skills while learning process-scheduling algorithms. The simulator allows the learner to navigate inside a computer motherboard and interact with its components in multi-projection environments such as CAVE-like systems (Cave Automatic Virtual Environment), on a desktop, in a Web browser, or using an HMD (head-mounted display) such as Google Cardboard.

The treatment of the Dyslexia Disorder requires patients to be disciplined and have a lot of reading practice so that they can reach a level of fluency and accuracy similar to people not diagnosed with this disorder. Due to cost or availability of health professionals, patients are not able, in general, to follow the treatment accordingly keeping a constant attendance. Besides, nowadays there are not many available tools to support health professionals towards dyslexia diagnosis. This paper presents an application developed for mobile devices, through which dyslexic users can practice their reading skills, turning the treatment accessible as well as helping health professionals as an auxiliary tool to diagnose their patients. This tool can be applied to support dyslexia diagnosis and to help people already diagnosed with this disorder training reading. To validate the use of this tool, the application was tested with some students of a private school in the city of São Paulo (Brazil). The results regarding usability aspects and the tool accuracy are also discussed.

Software libraries allow developers to create software projects upon basic functions already implemented. In this way, it is possible to focus on more complex activities to achieve the software solution aims. Software libraries features and availability on the Internet are the reason for these valuable project resources are widely used. However, there may be some issues in software projects that integrate several libraries, since they are independent projects that must work together. This paper presents LibViews, an information visualization application to create visual representations over libraries metrics and usage on software projects. LibViews was developed to provide a better understanding of libraries versions and their role in software projects, helping in the maintenance of these projects identifying previously unknown information. As use case, LibViews was applied in an university corporate software project, pointing out as a useful tool to understand the relationship between software project and its third-party libraries.

Interactive Learning objects (ILO) are explored in this paper in order to provide an improvement in teaching learning process, ensuring the monitoring of students by professor through the interaction provided by ILO. The article describes an ontology that defines and structure the classes of the elements of the ILO's metadata standard. This ontology is used as the basis for the development of a Virtual learning environment capable of running these objects and at the same time offer a system of tracking and monitoring the development of the student during the entire process. The ontology is validated through the results of the use of the ILO in the environment with a class of 20 students of the course of computer science.

Improving the way that totally or partially deaf people communicate with the world is a challenging task for our society. One way to improve their communication is to learn sign language, which is a visual language based on hand shapes, orientations, and movements of the hands, arms, or body, and facial expressions. This paper aims to present a 3D virtual reality environment to allow deaf users to communicate with each other in a real-time, synchronous, instantaneous fashion via an online chat room and to assist the teaching-learning process of Brazilian Sign Language (LIBRAS). A three-dimensional avatar was developed which can translate words or sentences from Portuguese to LIBRAS. It was performed two experiments to evaluate the communication via the chat room: (1) with chat history enabled (visible) and (2) with chat history disabled (invisible). These evaluations involved 30 end-users, which confirmed that the virtual environment as developed here is effective to distance classes.

The Augmented Reality applications differ from conventional in many ways such as add virtual objects in real scenes and, commonly, use markers for interaction. The unconventional way of interaction of these applications become the evaluation of usability essential. This paper presents the evaluation of usability of augmented reality applications based on heuristics of Nielsen, ISO 9241-11 and heuristics created by the authors. The evaluation was to assess the usability focus in relation to their users, so we used Usability Testing. It also presented the evaluation of three case studies form the marketing area.

Augmented reality applications differ from conventional applications in several aspects, for example, add virtual objects in real scenes, and often, uses markers for interaction. It is evident the need of methods to evaluate the usability of these applications, since the way of interaction is quite different from what the user is accustomed. This article presents metrics to usability evaluation of Augmented Reality applications created from the specifics of the technologies involved and from Nielsen heuristics, adapted to this context. It presents the result of application of these metrics on two augmented reality in the automotive area.

Gesture-based applications have particularities, since users interact in a natural way, much as they interact in the non-digital world. Hence, new requirements are needed on the software design process. This paper shows a software development process model for these applications, including requirement specification, design, implementation, and testing procedures. The steps and activities of the proposed model were tested through a game case study, which is a puzzle game. The puzzle is completed when all pieces of a painting are correctly positioned by the drag and drop action of users hand gesture. It also shows the results obtained of applying a heuristic evaluation on this game.

Interactive Digital Television Systems enable a new range of services involving the digital television programs, allowing the application and services inclusion with user interaction focus. Interactive shows create a new way to produce and deliver television content, where a show has some information beyond audio / visual content. This paper aims to present an interactive architecture, with the characteristics of an Interactive Service Provider that supports service storage and delivery on applications submitted along with interactive programs. We also present a proof of concept example, where an interactive application with the aim specified in the Brazilian Presidential Decree No. 4901 developed with the goal of social inclusion and information dissemination.