To ensure a certain degree of usability, a library website should be carefully designed, especially since end users constitute a multitude of people with different needs and demands. The focal objective of this research was to investigate how different types of end users (i.e. pupils, students, the working population, seniors and researchers) respond to a library website in terms of its effectiveness, efficiency and satisfaction, which together represent its usability. The answers were obtained by performing formal usability testing, including think-aloud protocol, log analysis and questionnaires. The results of the statistical analysis show that different groups of end users achieve different levels of effectiveness and efficiency, while there is no significant difference between groups in satisfaction level. The results also indicate that participants did not achieve the threshold for a usable website. Based on the identified weaknesses, researchers present recommendations for improving a website’s usefulness, especially for non-experienced users. This research has two main contributions: (1) the connection between the theoretical definition and practical use of ISO 9241-11 attributes and (2) a usability testing procedure with a measurement framework applicable for different types of users in a specific domain, which could be applied to other domains.

Business process diagrams represent an essential part of business process management activities, including process analysis, process-related communication, and process automation. While the majority of these artifacts are produced with modeling tools, there are still cases where hand-drawn diagrams are created, especially in the initial phases of process discovery and process innovation activities. The transformation of a hand-drawn diagram to digital format often presents several challenges. Thus, our efforts are directed towards investigating the effectiveness of an automatic transformation of hand-drawn diagrams into digital artifacts utilizing optical character recognition. To this aim, we performed empirical research in which subjects were instructed to redraw standardized process elements, which were afterward used for the training and testing set of machine-learning-based character recognition application. The findings obtained in the analysis showed that TensorFlow based and trained solution is capable of identifying hand-drawn process diagrams elements on different levels of accuracy. These insights may be considered when specifying or adapting the visual vocabularies of notations assuring appropriate visual distances between depictions of individual elements.

Despite efforts to promote digital inclusion for all, individuals with disabilities continue to experience a significant digital divide. Developing usable and accessible solutions also demands conducting user-based testing with real end users, particularly for users with disabilities, to detect and address real problems and barriers they experience and improve usability and accessibility based on their feedback through a user-centered approach. When including users with disabilities in user testing, additional attention must be paid to ensure that the testing is planned and carried out in such a way as to enable the successful and efficient integration of users with disabilities. In doing so, it is necessary to consider various restrictions related to users’ disabilities. By conducting a systematic literature review, we collected and analyzed the challenges of including users with disabilities in user-based testing and best practices that researchers can apply in future user-based testing with users with disabilities. In the existing literature, a positive trend toward publishing articles describing testing with users with disabilities is noticeable. There is also an apparent need for more reporting on some phases of the testing studies. The main result of this study is a list of challenges and best practices that are important in the different phases of user-based testing with users with disabilities.

The existing body of knowledge reveals that customisable websites may lead to an increase in accessibility and usability for people with disabilities. In this way, the main goal of this research was to investigate how people with dyslexia respond to a customised version of a website in terms of its effectiveness, efficiency, satisfaction and suitability when compared to the default version of the website. The customisation of the investigated website was enabled with the aid of integrated assistive technology that offers people with dyslexia the opportunity to adjust a website themselves in accordance with their individual needs, demands and preferences. They can do this by changing the parameters, such as font size, font type and contrast between the background and text. The answers to the research questions were obtained with complementary research methods and techniques, including formal usability testing, thinking aloud protocol, log analyses, questionnaires and interviews. The empirical results show that participants experienced more issues when interacting with the default website, and they enjoyed more benefits when using the customised website. Too much information on the screen, not enough graphic elements, issues with visual appearance and inappropriately presented information were identified as the most common issues when interacting with the default website. When using the customised website, all participants agreed on a better user experience and, as the majority of them reported, this was due to appropriate contrast and font size. Additionally, the majority of participants also expressed desire to use the individual website adjustments regularly in the future. The conclusions of this investigation are that the individual website adjustments used in this research can not only help to minimise issues, but also eliminate challenges that people with dyslexia have when interacting with a website. Therefore, the primary contributions of this research are the empirical insights of interaction with both the default and customised version of the website for people with dyslexia. Furthermore, this research also has three secondary contributions: (1) detailed presentation and application the general usability evaluation procedure to a specific target group (people with dyslexia); (2) recommendations to adapt the usability evaluation methods for people with dyslexia; and (3) the usage of quantitative measurement instruments for the evaluation of a website’s usability and suitability for people with dyslexia.

Unlike business process diagrams, where ISO/IEC 19510 (BPMN 2.0) prevails, high-level process landscape diagrams are being designed using a variety of standard- or semi-standard-based notations. Consequently, landscape diagrams differ among organizations, domains, and modeling tools. As (process landscape) diagrams need to be understandable in order to communicate effectively and thus form the basis for valid business decisions, this study aims to empirically validate the cognitive effectiveness of common landscape designs, including those BPMN-L-based, which represent a standardized extension of BPMN 2.0 specifically aimed at landscape modeling. Empirical research with 298 participants was conducted in which cognitive effectiveness was investigated by observing the speed, ease, accuracy, and efficiency of answering questions related to semantically equivalent process landscape diagrams modeled in three different notations: value chains, ArchiMate, and BPMN-L. The results demonstrate that BPMN-L-based diagrams performed better than value chain- and ArchiMate-based diagrams concerning speed, accuracy, and efficiency; however, subjects perceived BPMN-L-based diagrams as being less easy to use when compared to their counterparts. The results indicate that differences in cognitive effectiveness measures may result from the design principles of the underlying notations, specifically the complexity of the visual vocabulary and semiotic clarity, which states that modeling concepts should have unique visualizations.