This research examines situated behaviours and perceptions around textual navigation as it is practiced in situ by professionals working in various domains. In its investigation of interactions between human cognition and mediating artifacts, this research relies heavily on the resources of cognitive ethnography, including both observation and in-depth interviews with participants. Relevant contributions from the fields of information studies, book history, digital humanities, and human-computer interaction are presented to further elucidate the findings of this study. The findings reveal several emergent, interrelated navigational strategies, such as the use of annotations as navigational aids, reliance on automated interface actions, and the navigational value of interface metaphors. In further addressing the practice of textual navigation, this research also describes the creation of a prototype interface reflecting the study’s findings. This research proposes new ways of conceptualizing textual navigation and designing interfaces that support emergent textual interaction.

Web accessibility guidelines have textual representation and provide little support in systematic analysis and usage. The study hypothesizes that the guidelines can be reorganized and represented using the goal oriented technique and design patterns which will allow their usage in a more systematic manner and accommodate detailed analysis of the guidelines with other competing goals. For this study, knowledge from web designers’ experiences in using the guidelines, researchers’ findings, and the actual guidelines have been amalgamated. Six web designers have been consulted on a one-on-one basis and difficulties in using the guidelines for (1) specific scenarios, (2) systematic application, and (3) detailed systems analysis have been reported. Goal oriented modeling and design patterns have been introduced for (1) graphical representation of the guidelines using goal graphs, and (2) keeping the technical details separate from the goal graphs. The proposed representation allows for the accessibility guidelines to be systematically applied into interface design, and systems design using the goal oriented modeling technique.

Los materiales compuestos nanoestructurados son considerados una opción prometedora para la concepción de materiales multifuncionales. Sin embargo, la falta habitual de interacción entre los componentes orgánicos e inorgánicos en los materiales híbridos nanoestructurados comporta unas propiedades macroscópicas anisotrópicas que limitan su uso. Por ello, se hace necesario el diseño de la interfase formada entre los componentes mencionados a fin de mejorar sus prestaciones. En esta Tesis Doctoral se ha optado por el uso de dióxido de carbono supercrítico (scCO2) para la modificación superficial de nanopartículas inorgánicas y para la preparación de materiales híbridos nanoestructurados. Estos procesos supercríticos, diseñados como sostenibles, se proponen como sustitutos de técnicas convencionales que empleen disolventes orgánicos. El tratamiento superficial de nanopartículas de dióxido de titanio (TiO2) con octiltrietoxisilano se ha empleado como sistema de estudio para evaluar el uso de recubrimientos de alcoxisilanos bifuncionales como promotores de adhesión de partículas inorgánicas nanométricas. El scCO2 se emplea como disolvente del alcoxisilano para la silanización del TiO2. También se han llevado a cabo estudios fundamentales de solubilidad de octiltrietoxisilano en CO2 y de la cinética del proceso de silanización del TiO2. La modulación de las propiedades fisicoquímicas del scCO2 con la presión y la temperatura permite el control de las características del recubrimiento con silano. El proceso de silanización supercrítico se ha extendido a diferentes sistemas alcoxisilano-nanopartículas inorgánicas. Asimismo, se ha evaluado la tecnología de scCO2 para la preparación de materiales híbridos nanoestructurados que contengan nanopartículas inorgánicas silanizadas. El tratamiento superficial de las nanopartículas favorece la distribución homogénea de éstas en el material híbrido y mejora la interacción relleno-matriz orgánica. Se han procesado matrices biopoliméricas de interés en ingeniería tisular, compuestas de ácido poliláctico o la mezcla iv polimetilmetacrilato/policaprolactona, con adiciones de nanopartículas de TiO2 o hidroxiapatita, respectivamente. Para su procesado, se ha empleado scCO2 como no-disolvente utilizando la técnica Particles from a Compressed Anti-Solvent (PCA). Además, se han preparado partículas híbridas formadas por una mezcla lipídica de aceite de ricino hidrogenado y glicerilmonoestearato con adiciones de TiO2 y cafeína, con posibles aplicaciones en cremas para uso tópico. Estas partículas sólidas lipídicas se han obtenido usando la técnica Particles from Gas Saturated Solutions (PGSS) que emplea scCO2 como soluto. Por último, el proceso de silanización supercrítico se ha ensayado para materiales híbridos complejos multiescalados. Se han procesado materiales de base cemento empleando un proceso supercrítico de carbonatación-silanización en dos etapas. Primero, el cemento se carbonata de manera acelerada usando scCO2 como agente de carbonatación. Este cemento, ya carbonatado, se somete, finalmente, a un tratamiento hidrofóbico mediante silanización supercrítica, para su posible aplicación en confinamiento de residuos peligrosos en ambientes húmedos o como material de construcción duradero. / Nowadays, society is asking for a global changing in the way of manufacturing goods in a more sustainable manner. Indeed, the weight of the classical factors (cost, quality, appearance) influencing the acceptance of a certain good in the market have currently changed. Manufacturing requirements and regulations concerning environment protection (e.g., resource consumption, sustainability, toxicity, CO2 footprint, recycling potential) and quality features (e.g., product guarantees, durability against aggressive environments, corporate vision) are aspects of increasing concern. The competitive position of a company is influenced by seizing the opportunities and challenges and by managing the risks that the changeable market has. As a consequence, the industry is continuously looking for smart and innovative solutions for the design and manufacturing of materials with novel properties and increased added value, and for the production of materials already existing in the market in a more efficient manner. Nanostructured hybrid composites have emerged as a promising class of innovative materials for many industrial sectors (e.g., energy, optoelectronics, biomedicine, cosmetics). The multicomponent composition of these materials provides them with unique properties arising from the synergistic combination of the characteristics of their individual components structured at the nanolevel. Nevertheless, in numerous hybrid materials, the lack of coupling or bonding between the components often leads to anisotropic macroscopic properties, limiting their use. Hence, the interaction at the interphase between hybrid components must be properly engineered to enhance materials properties. In this PhD Thesis, the quest for sustainable and environmentally friendly processes led to the use of supercritical carbon dioxide (scCO2) for both the surface modification of nanometric inorganic particles and the preparation of nanostructured hybrid materials. These processes are designed for the replacement of conventional methods using organic solvents. vi Bifunctional alkoxysilane molecules, acting as adhesion promoters, are, herein, investigated for the surface modification of nanometric inorganic particles. The surface treatment of titanium dioxide (TiO2) nanoparticles with octyltriethoxysilane is taken as the model system for study. In terms of processing, scCO2 is used as the solvent of choice for alkoxysilanes for the surface modification of TiO2. Fundamental studies on the solubility of the used silane in CO2 in the pressure range 8-18 MPa at two different temperatures (318 and 348 K) and on the kinetics of the TiO2 silanization process are performed. For the scCO2-aided silanization process, studies are conducted to ascertain the effects and interactions of the operating variables on the properties of the final material. Results show that the tunable physicochemical properties of scCO2 with pressure and temperature (e.g., density, solvation power) allows the engineering control of the characteristics of the silane coating. Examples of the extension of the application of the supercritical silanization process to other sets of alkoxysilanes and inorganic nanoparticles are also presented. The preparation of hybrid materials including silanized inorganic nanoparticles and organic matrices is further tested using scCO2 technology. Surface treated nanoparticles are used to facilitate the homogeneous distribution of the nanoparticles within the matix and to improve the inorganic filler-organic matrix interaction. Biopolymeric matrices of either poly(L-lactic acid) (L-PLA) or the blend poly(methylmethacrylate)/poly(ε-caprolactone) (PMMA/PCL) loaded with nanometric titanium dioxide or hydroxyapatite, respectively, are prepared. To obtain these hybrid materials, scCO2 is employed as an anti-solvent, using the Particles from a Compressed Anti-Solvent (PCA) technique. Studies are performed to pursue the effect of the processing conditions on the morphology of the precipitated hybrid materials. The resulting material, obtained in the form of fibers, has suitable properties for its potential application in tissue engineering. In a different system, hybrid particles composed of a lipidic matrix (hydrogenated castor oil/glyceryl monostearate) loaded with silanized titanium dioxide and caffeine are prepared. The Particles from Gas Saturated Solutions (PGSS) technique, assisted by the use of scCO2 as a solute, is employed for the production of these solid lipid particles. The obtained hybrid material is evaluated concerning the drug carrier and release ability and the UV-shielding capacity. The UV-light protection and photoaging prevention capacity of the lipid-based hybrid material provide excellent properties for the use of these particles in the formulation of sunscreens and pharmaceutical dermal products. vii Finally, the possibility of extending the supercritical silane treatment to multiscale complex hybrid materials is assessed. The technology based on the use of scCO2 is presented for the two-step carbonation-silanization process of cement-based materials. In the first step, the carbonation of cement is accelerated using scCO2 as the carbonation agent. The effects of the cement formulation and process operation conditions on the microstructure and physicochemical properties of carbonated samples are evaluated. The carbonation process is followed by the hydrophobic treatment of the carbonated samples using a supercritical silanization method. The surface modification of carbonated cement with octyltriethoxysilane confers water repellence to the material. The carbonation-silanization process is scheduled and integrated to mitigate the consumption of raw materials and the use of facilities.

This is a report on research regarding the screen layout of Web-based training (WBT) programs, conducted with an eye toward providing evidence-based guidance for the design and development of WBT interfaces. Specifically, the study investigated the relative instructional benefits of two general types of WBT screen design, full-page and partial-page, in terms of both learner performance and learner satisfaction. The main hypotheses of the study were that the full-page design option would yield significantly better outcomes in both categories of interest.The study employed a mixed-method design, generating both quantitative and qualitative data. The main phase of the study was experimental, following a factorial design to explore the relationships between a single treatment variable (WBT screen design) in two treatment conditions (partial-page WBT design and full-page WBT design) and two dependent variables (learner performance and learner satisfaction). Both a full-page and a partial-page version of the same Web-based tutorial were created, and 129 self-selected undergraduate students who reported having little or no experience with the tutorial subject matter were randomly assigned into the two treatment groups. Performance data were collected as scores on the tutorial's 18-item, multiple choice final exam, and satisfaction data were collected via a 10-item satisfaction survey. In addition, 59 of the study participants were randomly selected to participate in post-study session interviews.The results of the study yielded no significant difference between the two treatment groups for either learner performance or learner satisfaction; thus, making it impossible to reject the null hypothesis for either of the two primary research questions. The conclusion of this study was that the presence or absence of scrolling alone is not a significant factor either in how well a person performs in a WBT program or how satisfied they are with the learning experience . However, while analysis of the post-study session interview data supported this conclusion, the fact that a large majority of the interviewees stated a preference for the full-page, non-scrolling WBT interface design suggests that some elements inherent in the full-page design might warrant further consideration and/or study.

<p>he focus of this research is to establish whether there is a difference in the way the genders perceive the visualization of mathematics, with specific reference to set theory. The influence of the computing experience of students on their perceptions was also investigated. Interfaces were created for the teaching of set theory for learners in the first class of secondary school. Since the mother tongue of most the pupils is Dari the interface was made available in both Dari and English. The interfaces were used to gather the data for the researc</p>

This research concerns the information design and visual design of graphical user interfaces (GUI) in the condition monitoring and condition-based maintenance (CBM) of production equipment. It also concerns various communicative aspects of a GUI, which is used to monitor the condition of assets. It applies to one Swedish vendor and its intentions to design information. In addition, it applies to the interaction between the GUI and its individual visual elements, as well as the communication between the GUI and the users (in four Swedish paper mills). The research is performed as a single case study. Interviews and observations have been the main methods for data collection. Empirical data is analyzed with methods inferred to semiotics, rhetoric and narratology. Theories in information science and regarding remediation are used to interpret the user interface design. The key conclusion is that there are no less than five different forms of information, all important when determining the conditions of assets. These information forms include the words, images and shapes in the GUI, the machine components and peripherals equipment, the information that takes form when personnel communicate machine conditions, the personnel’s subjective associations, and the information forms that relate to the personnel's actions and interactions. Preventive technicians interpret the GUI-information individually and collectively in relation to these information forms, which influence their interpretation and understanding of the GUI information. Social media in the GUI makes it possible to represent essential information that takes form when employees communicate a machine’s condition. Photographs may represent information forms as a machine’s components, peripherals, and local environment change over time. Moreover, preventative technicians may use diagrams and photographs in the GUI to change attitudes among the personnel at the mills and convince them, for example, of a machine’s condition or the effectiveness of CBM as maintenance policy.

This research examines situated behaviours and perceptions around textual navigation as it is practiced in situ by professionals working in various domains. In its investigation of interactions between human cognition and mediating artifacts, this research relies heavily on the resources of cognitive ethnography, including both observation and in-depth interviews with participants. Relevant contributions from the fields of information studies, book history, digital humanities, and human-computer interaction are presented to further elucidate the findings of this study. The findings reveal several emergent, interrelated navigational strategies, such as the use of annotations as navigational aids, reliance on automated interface actions, and the navigational value of interface metaphors. In further addressing the practice of textual navigation, this research also describes the creation of a prototype interface reflecting the study’s findings. This research proposes new ways of conceptualizing textual navigation and designing interfaces that support emergent textual interaction.

The venerable desktop metaphor is beginning to show signs of strain in supporting modern knowledge work. Traditional desktop systems were not designed to support the sheer number of simultaneous windows, information resources, and collaborative contexts that have become commonplace in contemporary knowledge work. Even though the desktop has been slow to evolve, knowledge workers still consistently manage multiple tasks, collaborate effectively among colleagues or clients, and manipulate information most relevant to their current task by leveraging the spatial organization of their work area. The potential exists for desktop workspaces to better support these knowledge work practices by leveraging the unifying construct of activity. Semantically-meaningful activities, conceptualized as a collection of tools (applications, documents, and other resources) within a social and organizational context, offer an alternative orientation for the desktop experience that more closely corresponds to knowledge workers' objectives and goals. In this research, I unpack some of the foundational assumptions of desktop interface design and propose an activity-centered model for organizing the desktop interface based on empirical observations of real-world knowledge work practice, theoretical understandings of cognition and activity, and my own experiences in developing two prototype systems for extending the desktop to support knowledge work. I formalize this analysis in a series of key challenges for the research and development of activity-based systems. In response to these challenges, I present the design and implementation of a third research prototype, the Giornata system, that emphasizes activity as a primary organizing principle in GUI-based interaction, information organization, and collaboration. I conclude with two evaluations of the system. First, I present findings from a longitudinal deployment of the system among a small group of representative knowledge workers; this deployment constitutes one of the first studies of how activity-based systems are adopted and appropriated in a real-world context. Second, I provide an assessment of the technologies that enable and those that pose barriers to the development of activity-based computing systems.

This thesis examines the role of intuition in the way that people operate unfamiliar devices, and the importance of this for designers. Intuition is a type of cognitive processing that is often　non-conscious and utilises stored experiential knowledge. Intuitive interaction involves the use of knowledge gained from other products and/or experiences. Therefore, products that people use intuitively are those with features they have encountered before. This position has been supported by two initial experimental studies, which revealed that prior exposure to products employing similar features helped participants to complete set tasks more quickly and intuitively, and that familiar　features were intuitively used more often than unfamiliar ones. Participants who had a higher level of familiarity with similar technologies were able to use significantly more of the　features intuitively the first time they　encountered them, and were significantly quicker at doing the tasks. Those who were less familiar with relevant technologies required more　assistance. A third experiment was designed to test four different interface designs on a remote control in order to establish which of two variables - a feature's appearance or its location - was more important in making a design intuitive to use. As with the previous experiments, the findings of Experiment 3 suggested that performance is　affected by a person's level of familiarity with similar technologies. Appearance (shape, size and labelling of buttons) seems to be the variable that most affects time spent on a task and intuitive uses. This suggests that the cues that people store in memory about a product's features depend on how the features look, rather than where on the product they are placed. Three principles of intuitive interaction have been developed. A conceptual tool has also been devised to guide designers in their planning for intuitive interaction. Designers can work with these in order to make interfaces intuitive to use, and thus help users to adapt more easily to new products and product types.

Interface colour scheme design is complex, but important. Most software allows users to choose the colours of single items individually and out of context, but does not acknowledge colour schemes or aid in their design. Creating colour schemes by picking individual colours can be time-consuming, error-prone, and frustrating, and the results are often mediocre, especially for those without colour design skills. Further, as colour harmony arises from the interactions between all of the coloured elements, anticipating the overall eff ect of changing the colour of any single element can be difficult. This research explores the feasibility of extending artistic colour harmony models to include factors pertinent to user interface design. An extended colour harmony model is proposed and used as the basis for an objective function that can algorithmically assess the colour relationships in an interface colour scheme. Its assessments have been found to agree well with human evaluations and have been used as part of a process to automatically create harmonious and usable interface colour schemes. A three stage process for the design of interface colour schemes is described. In the fi rst stage, the designer speci es, in broad terms and without requiring colour design expertise, colouring constraints such as grouping and distinguishability that are needed to ensure that the colouring of interface elements reflects their semantics. The second stage is an optimisation process that chooses colour relationships to satisfy the competing requirements of harmonious colour usage, any designer-specified constraints, and readability. It produces sets of coordinates that constitute abstract colour schemes: they de fine only relationships between coloured items, not real colours. In the third and fi nal stage, a user interactively maps an abstract scheme to one or more real colour schemes. The colours can be fi ne-tuned as a set (but not altered individually), to allow for such "soft" factors as personal, contextual and cultural considerations, while preserving the integrity of the design embodied in the abstract scheme. The colours in the displayed interface are updated continuously, so users can interactively explore a large number of colour schemes, all of which have readable text, distinguishable controls, and conform to the principles of colour harmony. Experimental trials using a proof-of-concept implementation called the Colour Harmoniser have been used to evaluate a method of holistic colour adjustment and the resulting colour schemes. The results indicate that the holistic controls are easy to understand and eff ective, and that the automatically produced colour schemes, prior to fi ne-tuning, are comparable in quality to many manually created schemes, and after fi ne-tuning, are generally better. By designing schemes that incorporate colouring constraints specifi ed by the user prior to scheme creation, and enabling the user to interactively fi ne-tune the schemes after creation, there is no need to specify or incorporate the subtle and not well understood factors that determine whether any particular set of colours is "suitable". Instead, the approach used produces broadly harmonious schemes, and defers to the developer in the choice of the fi nal colours.