Background: Despite the increasing attention for the positive effects of physical activity (PA), nearly half of the Dutch citizens do not meet the national PA guidelines. A promising method for increasing PA are mobile exercise applications (apps), especially if they are embedded with theoretically supported persuasive strategies (e.g., goal setting and feedback) that align with the needs and wishes of the user. In addition, it is argued that the operationalization of the persuasive strategies could increase the effectiveness of the app, such as the actual content or visualization of feedback. Although much research has been done to examine the preferences for persuasive strategies, little is known about the needs, wishes, and preferences for the design and operationalization of persuasive strategies.Objective: The purpose of this study was to get insight in the needs, wishes, and preferences regarding the practical operationalization of persuasive strategies in a mobile application aimed at promoting PA in healthy inactive adults.Methods: Five semistructured focus groups were performed. During the focus groups, the participants were led into a discussion about the design and operationalization of six predefined theory-based persuasive strategies (e.g., self-monitoring, feedback, goal setting, reminders, rewards, and social support) directed by two moderators. The audio-recorded focus groups were transcribed verbatim and analyzed following the framework approach.Results: Eight men and 17 women between 35 and 55 years (mean age, 49.2) participated in the study. Outcomes demonstrated diverse preferences for implementation types and design characteristics of persuasive strategies in mobile applications. Basic statistics (such as distance, time and calories), positive feedback based on easy-to-achieve goals that relate to health guidelines, and motivating reminders on a relevant moment were preferred. Participants had mixed preferences regarding rewards and a social platform to invite other users to join PA.Conclusions: Findings indicated that in mHealth applications for healthy but inactive adults, persuasive strategies should be designed and implemented in a way that they relate to health guidelines. Moreover, there is a need for an app that can be adapted or can learn based on personal preferences as, for example, preferences with regard to timing of feedback and reminders differed between people.
An essential condition to use mathematics to solve problems is the ability to recognize, imagine and represent relations between quantities. In particular, covariational reasoning has been shown to be very challenging for students at all levels. The aim of the project Interactive Virtual Math (IVM) is to develop a visualization tool that supports students’ learning of covariation graphs. In this paper we present the initial development of the tool and we discuss its main features based on the results of one preliminary study and one exploratory study. The results suggest that the tool has potential to help students to engage in covariational reasoning by affording construction and explanation of different representations and comparison, relation and generalization of these ones. The results also point to the importance of developing tools that elicit and build upon students' self-productions
This project addresses the fundamental societal problem that encryption as a technique is available since decades, but has never been widely adopted, mostly because it is too difficult or cumbersome to use for the public at large. PGP illustrates this point well: it is difficult to set-up and use, mainly because of challenges in cryptographic key management. At the same time, the need for encryption has only been growing over the years, and has become an urgent problem with stringent requirements – for instance for electronic communication between doctors and patients – in the General Data Protection Regulation (GDPR) and with systematic mass surveillance activities of internationally operating intelligence agencies. The interdisciplinary project "Encryption for all" addresses this fundamental problem via a combination of cryptographic design and user experience design. On the cryptographic side it develops identity-based and attribute-based encryption on top of the attribute-based infrastructure provided by the existing IRMA-identity platform. Identity-based encryption (IBE) is a scientifically well-established technique, which addresses the key management problem in an elegant manner, but IBE has found limited application so far. In this project it will be developed to a practically usable level, exploiting the existing IRMA platform for identification and retrieval of private keys. Attribute-based encryption (ABE) has not reached the same level of maturity yet as IBE, and will be a topic of further research in this project, since it opens up attractive new applications: like a teacher encrypting for her students only, or a company encrypting for all employees with a certain role in the company. On the user experience design side, efforts will be focused on making these encryption techniques really usable (i.e., easy to use, effective, efficient, error resistant) for everyone (e.g., also for people with disabilities or limited digital skills). To do so, an iterative, human-centred and inclusive design approach will be adopted. On a fundamental level, scientific questions will be addressed, such as how to promote the use of security and privacy-enhancing technologies through design, and whether and how usability and accessibility affect the acceptance and use of encryption tools. Here, theories of nudging and boosting and the unified theory of technology acceptance and use (known as UTAUT) will serve as a theoretical basis. On a more applied level, standards like ISO 9241-11 on usability and ISO 9241-220 on the human-centred design process will serve as a guideline. Amongst others, interface designs will be developed and focus groups, participatory design sessions, expert reviews and usability evaluations with potential users of various ages and backgrounds will be conducted, in a user experience and observation laboratory available at HAN University of Applied Sciences. In addition to meeting usability goals, ensuring that the developed encryption techniques also meet national and international accessibility standards will be a particular point of focus. With respect to usability and accessibility, the project will build on the (limited) usability design experiences with the mobile IRMA application.