Using a common accessibility profile to improve accessibility

People have difficulties using computers. Some have more difficulties than others. There is a need for guidance in how to evaluate and improve the accessibility of systems for users. Since different users have considerably different accessibility needs, accessibility is a very complex issue.ISO 9241-171 defines accessibility as the "usability of a product, service, environment or facility by people with the widest range of capabilities." While this definition can help manufacturers make their products more accessible to more people, it does not ensure that a given product is accessible to a particular individual.A reference model is presented to act as a theoretical foundation. This Universal Access Reference Model (UARM) focuses on the accessibility of the interaction between users and systems, and provides a mechanism to share knowledge and abilities between users and systems. The UARM also suggests the role assistive technologies (ATs) can play in this interaction. The Common Accessibility Profile (CAP), which is based on the UARM, can be used to describe accessibility.The CAP is a framework for identifying the accessibility issues of individual users with particular systems configurations. It profiles the capabilities of systems and users to communicate. The CAP can also profile environmental interference to this communication and the use of ATs to transform communication abilities. The CAP model can be extended as further general or domain specific requirements are standardized.The CAP provides a model that can be used to structure various specifications in a manner that, in the future, will allow computational combination and comparison of profiles.Recognizing its potential impact, the CAP is now being standardized by the User Interface subcommittee the International Organization for Standardization and the International Electrotechnical Commission

Assessing Usability of Products in the Low Vision Field

Student Number : 9804058J - MSc dissertation - School of Information and Electrical Engineering - Faculty of Engineering and the Built EnvironmentThis paper presents the implementation of usability engineering into a device to meet the requirements of a Visually Impaired Person (VIP). Users of such a device may suffer from conditions such as Macular Degeneration, Diabetes and HIV/AID’s related disorders. Since these disorders affect a person’s vision, the device enlarges the desired text to reduce the effects of loss of vision. Other functionality may include image manipulation and colour modification. A usability engineering framework is incorporated into the design as well as accommodating user requirements in the design process. Usability principles are implemented, hence meeting the aims of effectiveness, efficiency, learnability, satisfaction and context of use. The device is examined via heuristic evaluation and usability testing from specialists and end users, with comments, ratings and times recorded. Research indicates that this device successfully implements usability engineering techniques and provides a cost effective, highly functional device for the VIP

Usability-Ergebnisse als Wissensressource in Organisationen

Durch den Prozess der nutzerzentrierten Softwareentwicklung sammeln Organisationen wichtige Erkenntnisse über die Nutzer ihre Produkte, deren Arbeitsaufgaben und über die Nutzungskontexte, in dem diese sie anwenden. Diese Arbeit untersucht, wie derartige Usability-Ergebnisse in einer Organisation langfristig als Durch den Prozess der nutzerzentrierten Softwareentwicklung sammeln Organisationen wichtige Erkenntnisse über die Nutzer ihrer Produkte, deren Arbeitsaufgaben und über die Nutzungskontexte, in denen sie angewendet werden. Diese Arbeit untersucht, wie derartige Usability-Ergebnisse in einer Organisation langfristig als Wissensressource eingesetzt werden können, um die Usability zukünftiger Produkte zu verbessern und die Effizienz des nutzerzentrierten Entwicklungsprozesses zu optimieren. Im Fokus stehen dabei interne Usability-Beauftragte als Anwender dieser Wissensressource: Da diese innerhalb ihrer Organisation für die dort entwickelten Produkte verantwortlich sind, haben sie ein besonders hohes Interesse an der nachhaltigen Nutzung der erhobenen Usability-Ergebnisse. Zu einer organisationsinternen Nutzung von Usability-Ergebnissen existieren bereits Ansätze aus der Forschung zu nutzerzentrierten Entwicklungsprozessen im Bereich der Mensch-Computer-Interaktion, die unterschiedliche Ziele verfolgen. (Hughes, 2006; Douglas, 2007; Vilbergsdottir et al., 2014). Einen frühen Ansatz stellt Andre et al. (2001) mit dem User Action Framework vor, dessen Anwendung jedoch aufwendig sein kann (Hornbæk et al., 2008). Vorschläge für die Klassifizierung von empirischen Usability-Ergebnissen werden bislang vor allem im Kontext der Forschung zu Usability-Methoden eingesetzt (etwa Lavery et al., 1997; Hornbæk et al., 2008). In anderen Bereichen finden sie jedoch keine breite Anwendung, da sie nicht auf die Anwendungsfälle für Usability-Information in Organisationen abgestimmt sind. Als eine zentrale Fragestellung dieser Arbeit wird daher untersucht, für welche Anwendungsfälle eine Sammlung von Usability-Ergebnissen eingesetzt werden kann (Forschungsfrage RQ1). Dafür werden qualitativ ausgerichtete Interviews (n=8) mit internen Usability-Beauftragten sowie Fokusgruppen in zwei Organisationen durchgeführt. Im Rahmen dieser Studien können außerdem die Anforderungen an die Wissensorganisation und an die Informationsinteraktion für die Nutzung von Usability-Ergebnissen als Wissensressource analysiert werden (RQ2). Die Anforderungen werden als ein prototypisches Usability-Informationssystem umgesetzt, welches den Zugang zu einer Sammlung von Usability-Ergebnissen bereitstellt. In einer Studie mit Usability-Beauftragten (n=11) wird dieses System evaluiert, um Rückschlüsse auf die zugrunde liegenden Anforderungen zu ermöglichen. Im Rahmen der Studie werden zudem die Entscheidungsprozesse diskutiert, die angewendet werden, wenn Usability-Ergebnisse auf andere Kontexte übertragen oder verallgemeinert werden sollen (RQ3). Weiterhin werden die Faktoren und Barrieren untersucht, welche die Akzeptanz von Usability-Ergebnissen als Wissensressource in einer Organisation beeinflussen (RQ4). Die Untersuchungen zeigen, dass Usability-Ergebnisse bereits in vielen Organisationen gesammelt und gezielt eingesetzt werden. Die erhobenen Anwendungsfälle (RQ1) umfassen die Übertragung von vorhandenen Ergebnissen auf aktuelle Gestaltungsentscheidungen, Lernprozesse, analytische Fragestellungen und die Verallgemeinerung zu internen Richtlinien. Zu den identifizierten Anforderungen für die Organisation von Usability-Wissen (RQ2) gehört die Kombination von produktübergreifenden und produktbezogenen Metadaten. Die empirischen Evaluierungsergebnisse aus Nutzertests sollten mit den zugrunde liegenden Daten, vor allem aber mit den resultierenden Lösungsvorschlägen verknüpft werden. Bei der Gestaltung der Informationsinteraktion sollten die gezielte Suche, der Umgang mit potenziell unbekannter oder wechselnder Terminologie, aber auch explorative Such- und Lernprozesse unterstützen werden. Wenn Usability-Ergebnisse in einer Organisation mit dem Ziel der Vollständigkeit erhoben werden, können darauf auch Funktionen für die quantitative Analyse und für die Prozessbewertung aufbauen. Für die Bewertung der Übertragbarkeit von Usability-Ergebnissen (RQ3) sind eine Reihe von Entscheidungskriterien und Hinweisen relevant, anhand derer ihre Zuverlässigkeit überprüft und der Erhebungskontext hinsichtlich der Relevanz für eine aktuelle Fragestellung bewertet werden kann. Die Akzeptanz der Anwendung von Usability-Wissen (RQ4) erscheint primär von dem Aufwand abhängig, der für die Erschließung der Ergebnisse erforderlich ist. Die meisten der Teilnehmer bewerten den Aufwand im Verhältnis zu den erwarteten Vorteilen jedoch als angemessen. Mögliche Barrieren für die Wissensteilung können aus der Befürchtung entstehen, die Kontrolle über die Interpretation der Ergebnisse zu verlieren, sowie aus der Wahrnehmung als öffentliche Kritik an den jeweiligen Produktverantwortlichen. Die Ergebnisse dieser Arbeit können dabei helfen, die Unterstützung für die Nutzung von Usability-Ergebnissen als Wissensressource auf die erhobenen Anwendungsfälle auszurichten. Dafür werden Empfehlungen zu möglichen Ausrichtungen eines Usability-Informationssystems in Organisationen gegeben. Die Ergebnisse verweisen außerdem auf das große Potenzial für weitere Forschungsvorhaben in diesem Bereich, sowohl in Hinblick auf eine bessere Unterstützung des Wissensmanagements von Usability-Ergebnissen als auch in Bezug auf die Übertragung der grundlegenden Erkenntnisse dieser Arbeit auf andere Anwendungsdomänen, etwa im Bereich des Managements von Forschungsdaten.User centered software development provides organizations with valuable insights about the users of their software, about their work tasks and the various contexts in which a product is used. This dissertation explores how organizations can profit even more from such results in the long term by using them as an internal knowledge resource for improving the usability of future products and for increasing the efficiency of user centered processes. This topic will be investigated for in-house usability consultants as the primary target group of such a resource. In-house consultants are responsible for the quality of the products developed in their company, and the sustainable management of internal usability results therefore is of particular interest to them. In the research field of human computer interaction and user centered design, several approaches have already been proposed which can be used to systematize usability results in order to pursue a variety of goals (e.g. Hughes 2006; Douglas 2007; Vilbergsdottir et al. 2014). The User Action Framework (Andre et al. 2001) is an important contribution in this area. Its implementation, however, may prove to be difficult for many organizations because applying it was found to be resource intensive (Hornbæk et al., 2008). Other classification systems for usability problems have predominantly been in use in scientific studies on the evaluation of usability methods (e. g. Lavery et al. 1997; Hornbæk & Frøkjær 2008). These approaches have not been widely adopted because of the efforts involved in applying them, and because they do not take into account relevant use cases for usability information in organizations. The identification of use cases for the internal application of usability results therefore constitutes an important research question of this dissertation (research question RQ1). Qualitative interviews with in-house usability consultants (n=8) as well as focus groups in two organizations are conducted in order to investigate this question and to elicit usage requirements of an usability information system (research question RQ2). A prototypical usability information system implements these requirements based on a set of realistic usability results. The system and the proposed requirements are evaluated in an additional study with usability consultants (n=11). In the context of this study, criteria for reusing and generalizing usability results can be examined from the point of view of the participants (research question RQ3). In addition, the factors and barriers influencing the process of sharing and using usability knowledge have been investigated (research question RQ4). Results demonstrate that usability results have already been collected and applied to different use cases in many organizations (RQ1), including their direct application to current design decisions, learning and exploration, analytic questions, and the creation of internal usability standards. The organization of usability results (RQ2) requires a combination of product-specific characteristics with more general attributes as metadata for search and analysis. Results from user studies should be linked to the underlying empirical data and to the resulting design recommendations. Requirements for information interaction include support for the targeted search for usability results, dealing with potentially unknown or changing terminology, as well as possibilities for exploratory search and learning. If results are collected comprehensively in an organization, features for information analysis can be used to support the improvement of development processes. A number of different criteria are used to assess the reliability of usability results and the fit between the context in which a result was elicited and the context to which the result is to be applied. These aspects together provide the basis for deciding about the transferability of results (RQ3). Acceptance of the application of usability results as an information resource (RQ4) primarily depends on the amount of effort which is required for documenting these results. However, most participants expect the benefits to outweigh these efforts. Possible barriers for sharing usability results also include concerns about the loss of control over their interpretation as well as the perception of published results as criticism by those who are responsible for a product. In addition to describing existing practices, the results of this dissertation are intended to offer assistance for the application of usability results as an information resource in different use cases. Accordingly, recommendations about different categories of usability information systems are presented. The findings indicate further possibilities for research with the goal of improving knowledge management for usability results and may also be applied to other domains such as research data management

Avaliação de usabilidade para os computadores de mão: um estudo comparativo entre três abordagens para ensaios de interação

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção.A usabilidade dos computadores de mão e das aplicações para estes equipamentos é um fator determinante do sucesso deste segmento da computação móvel. As necessidades e características do usuário móvel, o contexto de uso dos computadores de mão, as características das aplicações e as limitações físicas destes equipamentos são fatores que irão influenciar a interação e devem ser considerados tanto no projeto das interfaces quanto na avaliação de usabilidade destes equipamentos. Esta pesquisa teve como objetivo investigar qual a influência do contexto de avaliação nos resultados da avaliação de usabilidade da interface com o usuário de uma aplicação de Internet móvel para telefone celular baseada na técnica de ensaios de interação. Os ensaios de interação foram realizados segundo três diferentes abordagens, utilizando: (i) emulador operado em laboratório, (ii) telefone celular operado em laboratório e (iii) telefone celular operado em campo. Os resultados do experimento mostraram que é possível obter bons resultados na avaliação de usabilidade de uma interface de um computador de mão utilizando um emulador no computador, desde que o contexto de avaliação seja definido da maneira mais próxima possível ao contexto de uso, assegurando principalmente a similaridade entre as interfaces. Também foi constatado que a posição do usuário e a maneira como ele segura um computador de mão são fatores que afetam a interação com a interface e devem ser considerados, assim como a realização de tarefas adicionais paralelas podem interferir nos resultados da usabilidade medida e nos índices de desempenho das avaliações. Novas técnicas que possibilitem ao usuário utilizar um computador de mão em situações reais, ou seja, em movimento, em vários ambientes diferentes, estando exposto às interferências externas, ao mesmo tempo que permitam registrar a interação são necessárias para auxiliar nas avaliações de usabilidade dos computadores de mão. Neste sentido, o sistema envolvendo uma minicâmera sem fio, desenvolvido especialmente para este trabalho, mostrou ser uma excelente solução para auxiliar na realização de ensaios de interação sempre que for necessário registrar as imagens e o áudio da interação do usuário com um computador de mão, independentemente do local da avaliação

Modeling end user performance perspective for cloud computing systems using data center logs from big data technology

Information system performance measurement has been a concern for software engineers since the early days of the field’s development. Over time, numerous techniques and methodologies have been developed that help engineers and companies better understand, manage and improve the performance that the end users perceive when using information systems in their daily operations. Some performance measurement techniques employ surveys that investigate which aspects satisfy or do not satisfy end user requirements. Other performance measurement techniques simulate the same operations across different services in order to compare performance given a similar workload. Yet another approach that has been experimented slightly modifies the data exchanged between clients and servers in order to include components that help with tracing the performance of different operation statuses. When we consider surveys or questionnaires as a performance measurement technique, they do not include detailed information about the sources of problems that may be impacted by the time of day, the responder’s mood and many other human factors, thus masking the root cause and they are not sufficiently interactive to allow for a timely reaction when there is a performance problem. Simulation is also proposed as a potential solution where the same operations, over different platforms, correctly report fundamental characteristics of performance. This approach however, removes the user’s perspective. It is difficult to assume that a simulation would be able to, with the current state of technology, accurately reflect the complexity of a user’s reasoning and decisions regarding the use of a specific information system in a particular way. Finally, the manipulation of the transactional data between client and hosts could affect the confidentially and refutability of the data used to determine the performance; if an information system includes the possibility of data being modified, even slightly, the end user could lose trust in it, negatively affecting the human-machine relation. The question that is considered here is how can the end user performance perspective of cloud computing-based applications be modeled in a way so that timely analysis can be enacted upon the information? The best possible solution for understanding performance from the end user’s perspective could emerge from combining the completeness of interactive surveys with the controlled environment of simulations and the traceability of packet manipulation, while minimizing the weaknesses of each of these techniques. As companies continue to rollout cloud computing infrastructures and systems, the difficulty with performance measurement increases due to a number of factors, most noticeably, the increased complexity of these systems in comparison with their previous versions as well as the unreliability of the performance experience as perceived by the end user, which is influenced by socio-technical aspects such as technical knowledge, trust, system performance, availability and efficacy (Armbrust, Fox, & Griffith, 2009) (Gruschka & Jensen, 2010) (Grobauer, Walloschek, & Stocker, 2011). In order to be able to address these particular challenges, one possible solution could be to make better use of the ubiquitous industry standard performance logs. Performance logs are textual representations of different resource consumption and activities performed in the various operational cloud system components. Logs have been extensively deployed in the industry and used for both troubleshooting and punctual investigations of performance problems. In this research, logs are explored more extensively in order to address the need for precision, granularity and responsiveness within the decision time required for the current management/prediction challenges. The amount and granularity of the data harvested could potentially be massive. Each of the analyzed hosts or network components can generate as much as 800 KB of data per minute. This could quickly turn into a very large amount of data that is difficult to process and access using traditional SQL-based technologies. One of the possible alternatives for resolving this issue is employing Big Data technologies such as the Hadoop Distributed File System and Apache Spark in order to interactively collect the data from multiple sources and process the individual files simultaneously, which would prove difficult using classic relational database technology. This research proposes a novel performance measurement model for cloud-based information systems as perceived by end users, with many practical applications in the domain of service level measurement and performance prediction. It identifies meaningful and actionable data center logs of low-level direct and derived measurements to model the end user performance perspective. The cloud computing measurement model and quality characteristics presented by Bautista’s framework (Bautista, Abran, & April, 2012) are implemented and experimented. The model for the end user performance perspective for cloud computing systems using data center logs from Big Data technology expands Bautista’s original work by proposing the utilization of a performance indicator and including end user response in order to forecast possible performance anomalies. A large-scale experimentation is described where the measures are analyzed using a modern Big Data infrastructure in order to model the end user performance perspective as an expression of performance indicators based on the service level agreement for the cloud computing services studied. The experimentation addresses the research question and offers a solution avenue for modelling the end user performance perspective of cloud computing based applications in future service level agreements so that a timely analysis of the data can be expected and a predictive algorithm developed to anticipate upcoming performance issues

A Theory and Practice of Website Engagibility

This thesis explores the domain of website quality. It presents a new study of website quality - an abstraction and synthesis, a measurement methodology, and analysis - and proposes metrics which can be used to quantify it. The strategy employed involved revisiting software quality, modelling its broader perspectives and identifying quality factors which are specific to the World Wide Web (WWW). This resulted in a detailed set of elements which constitute website quality, a method for quantifying a quality measure, and demonstrating an approach to benchmarking eCommerce websites. The thesis has two dimensions. The first is a contribution to the theory of software quality - specifically website quality. The second dimension focuses on two perspectives of website quality - quality-of-product and quality-of-use - and uses them to present a new theory and methodology which are important first steps towards understanding metrics and their use when quantifying website quality. Once quantified, the websites can be benchmarked by evaluators and website owners for comparison with competitor sites. The thesis presents a study of five mature eCommerce websites. The study involves identifying, defining and collecting data counts for 67 site-level criteria for each site. These counts are specific to website product quality and include criteria such as occurrences of hyperlinks and menus which underpin navigation, occurrences of activities which underpin interactivity, and counts relating to a site’s eCommerce maturity. Lack of automated count collecting tools necessitated online visits to 537 HTML pages and performing manual counts. The thesis formulates a new approach to measuring website quality, named Metric Ratio Analysis (MRA). The thesis demonstrates how one website quality factor - engagibility - can be quantified and used for website comparison analysis. The thesis proposes a detailed theoretical and empirical validation procedure for MRA

Effects of Quality of service on video-chat users

The fundamental objective of this thesis is to single out the most influential quality and usability factors on video-chat services. The main reason for pursuing the research was that by discovering these specific quality factors engineers and scientists will be able to set the right priorities when they work on either improving or inventing a better quality of video-chat services. Even though, the complete study of human behavior is out of the scope of engineers and technologists, knowing the basic preferences of users towards the current digital communication media, such as video-chat services is significant. It is only when technologists understand the users’ behavior and their interaction with technology that they could improve or invent new products / services that consider the users’ overall experience. Therefore, this thesis has conducted basic behavioral and emotional studies by using method from the social sciences in order to give conclusions on the major technical quality factors that affect users most

Effective design, configuration, and use of digital CCTV

It is estimated that there are five million CCTV cameras in use today. CCTV is used by a wide range of organisations and for an increasing number of purposes. Despite this, there has been little research to establish whether these systems are fit for purpose. This thesis takes a socio-technical approach to determine whether CCTV is effective, and if not, how it could be made more effective. Humancomputer interaction (HCI) knowledge and methods have been applied to improve this understanding and what is needed to make CCTV effective; this was achieved in an extensive field study and two experiments. In Study 1, contextual inquiry was used to identify the security goals, tasks, technology and factors which affected operator performance and the causes at 14 security control rooms. The findings revealed a number of factors which interfered with task performance, such as: poor camera positioning, ineffective workstation setups, difficulty in locating scenes, and the use of low-quality CCTV recordings. The impact of different levels of video quality on identification and detection performance was assessed in two experiments using a task-focused methodology. In Study 2, 80 participants identified 64 face images taken from four spatially compressed video conditions (32, 52, 72, and 92 Kbps). At a bit rate quality of 52 Kbps (MPEG-4), the number of faces correctly identified reached significance. In Study 3, 80 participants each detected 32 events from four frame rate CCTV video conditions (1, 5, 8, and 12 fps). Below 8 frames per second, correct detections and task confidence ratings decreased significantly. These field and empirical research findings are presented in a framework using a typical CCTV deployment scenario, which has been validated through an expert review. The contributions and limitations of this thesis are reviewed, and suggestions for how the framework should be further developed are provided

Capturing user requirements for smart hometechnology, to support industry practice

The home-orientated technology industry has grown rapidly since the 1980s. This movement has been catalysed by an intensive evolution in technology development and is reflected by academic and industry interest in the area. In combination with the ubiquity of digital consumer products, such interest has driven the re-emergence of the smart home as an ideal that, with a paradigmatic shift in human interaction with their environment, will improve lifestyle and support independent living. Accordingly, the smart home has come to represent an aspirational vision of the future. However, despite the renewed interest in the area and a legacy of technology that has resulted in confused, frustrated and disillusioned users, little research has been undertaken to identify the perception of the user towards the smart home. Consequently, the provision of guidance for industry practice and designers is severely limited. To counteract technology that does not support user needs and to ensure the efficacy of the smart home, this research captures the perception of the user towards existing and future technology and reflects on the needs of state of the art industry practice. In study one, eight workshops (N=55) captured positive anticipation and attitudes of users towards the smart home but with some concerns and contradictory needs and requirements. A contextual enquiry (N=12), incorporating a probe study and home interview, explored technology usage in more depth. Differences in basic technology usage, such as heating and lighting, revealed complex meanings behind the assumed use of technology. User needs were embodied in a co-design workshop (N=8) in which prototypes for the control of their smart home were modelled. Concepts for the smart home are distinguished by functionality, the locus of control for human-system interaction, and the nature of interaction. Despite the acknowledgement of the value of perceptive and aware technology, users must perceive empowerment and ownership of all activity in the home. To explore current practice in design and development for the smart home, interviews were conducted with industry professionals (N=18) from twelve companies and analysed according to a grounded theory method with a constructionist approach. User centred design was found to be prevalent in the smart home industry but compromises remained. The user perceptions towards the smart home illustrate the challenges that the industry must overcome, and provide a case study example of including the user throughout the `fuzzy front end' of the design process. Although user centred design is often deemed a panacea in the development of successful products, this study has found that disparate views on user centred design have caused a misrepresentation of the user and their importance. It is clear that companies want to be people-centred but effective user centred design practice is seemingly not arbitrary. The most immediate needs for successful professional practice of user centred smart home design have been identified in this study and are supported with the provision of guidance that will contribute to their understanding.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Latent Print Examination and Human Factors: Improving the Practice Through a Systems Approach: The Report of the Expert Working Group on Human Factors in Latent Print Analysis

Fingerprints have provided a valuable method of personal identification in forensic science and criminal investigations for more than 100 years. Fingerprints left at crime scenes generally are latent prints—unintentional reproductions of the arrangement of ridges on the skin made by the transfer of materials (such as amino acids, proteins, polypeptides, and salts) to a surface. Palms and the soles of feet also have friction ridge skin that can leave latent prints. The examination of a latent print consists of a series of steps involving a comparison of the latent print to a known (or exemplar) print. Courts have accepted latent print evidence for the past century. However, several high-profile cases in the United States and abroad have highlighted the fact that human errors can occur, and litigation and expressions of concern over the evidentiary reliability of latent print examinations and other forensic identification procedures has increased in the last decade. “Human factors” issues can arise in any experience- and judgment-based analytical process such as latent print examination. Inadequate training, extraneous knowledge about the suspects in the case or other matters, poor judgment, health problems, limitations of vision, complex technology, and stress are but a few factors that can contribute to errors. A lack of standards or quality control, poor management, insufficient resources, and substandard working conditions constitute other potentially contributing factors