Computer Numerically Controlled (CNC) machines are common pieces of equipment in manufacturing plants. In recent years, CNC-user interfaces have been evolving from CNC command languages to menu based and direct manipulation interfaces. However, there have been few efforts to evaluate CNC-user interfaces and to identify those interface features that have major effects on the usability of CNC machines. Thus, an objective assessment of the improvement achieved from different user interface technologies is needed. Two experiments compared the effectiveness of two types of CNC-user interfaces: command-language and direct manipulation interfaces. Two command language interfaces and one object oriented interface were designed and evaluated in terms of human performance and preferences. Experiment 1 compared two command-language interfaces: Layout 1 was a simulation of the original control panel of a CNC-Dyna machine, and Layout 2 was a modified user interface based on the analysis of the Dyna control language. Four factors were manipulated: (1) users’ level of expertise, (2) layouts, (3) tasks, and (4) trials. It was found that both groups of subjects completed the tasks faster using Layout 2 than Layout 1. Modification tasks were performed faster than copy tasks. Subjects’ responses to a questionnaire indicated that Layout 2 was preferred over Layout 1 in several categories. In Experiment 2 subjects used a command-language interface and a direct-manipulation interface. Four factors were manipulated: (1) experimental sessions (two sessions with a one-week interval between them), (2) users’ level of expertise, (3) tasks, and (4) trials. The interval between sessions had a significant effect on task completion time when the command-language interface was used, but there was not a significant effect of this factor when the direct-manipulation interface was used. Subjects’ subjective responses indicated a stable preference for the direct-manipulation interface in several categories of usability. / Ph. D.

A common concern for people using computer databases is becoming "lost" within the complex hierarchy of entries. Most direct manipulation interface design guidelines suggest designers should include a feature for “undoing” user inputs (Smith and Mosier, 1986). In the case of a database, undo translates to backtracking support. The first purpose of this research was to confirm that computer-supported backtracking tools reduce navigation time over manual backtracking. The second purpose was to compare navigation times among a subset of backtracking tools. The third purpose was to determine if users prefer to use one or more backtracking tools significantly more than others. Four backtracking tools were developed by crossing two factors: History (history list vs no history list) and Level (component vs entry). History list indicates the user may view a chronological listing of nodes that have been viewed and directly select a destination node. No history list means the user must backtrack through each visited node with no shortcuts. Component indicates the backtracking tools operate only at the lowest level, or smallest definable node, of the tree-like database structure. Entry means that backtracking occurs at the higher parent node. Thus, multiple components make up an entry . In addition to the four computer backtracking tools, overall navigating and manual backtracking was done using a hierarchical Table of Contents. The tools were evaluated in an experimental, hierarchical, direct-manipulation database. Trials were conducted in the form of a multiple-choice information retrieval task. The independent variables included the backtracking tool (four-computer supported, one-manual) and the backtrack Task Length. The dependent measures included navigation time, the frequency with which the computer tool was used over manual backtracking (Table of Contents), and questionnaire responses. The results of this study provided some of the first solid support for the many guidelines that have been written recommending user recovery, or undo support. Backtracking with any of the four computer-supported tools resulted in a significantly smaller navigation time than manual backtracking using the Table of Contents. Subjects using either of the entry tools had consistent backtracking times across trials regardless of backtrack task length. When provided with a history list, subjects in the entry condition had significantly smaller navigation times than subjects in the component condition. Users did not show any differences between computer tools in rated efficiency, ease of use, or objective preference measures. / Master of Science

A systems engineering life-cycle approach is used to design the Facilities Automated Scheduling Tool (FAST) for the Facilities Branch of the ABC Company. The emphasis of the proposed design is the human factors criteria that are used to optimize the human-computer interface (HCI). The need identified by the Facilities Branch is that the current manual project tracking system takes three weeks to gather the information required to initiate a request for change (RFC). Paperwork is cumbersome, data files are difficult to locate, and the Facilities Specialists are inundated with fragmented reports filed away in cabinets that are taking up what little free space the office has left. Therefore, the requirements for the system are established, options considered, and a recommended design is achieved which will reduce the number of file cabinets by 80%, enable a project to be input into the system in fifteen minutes, and reduce the number of data input specialists from three to one, saving the company time and money. FAST is essential to the Facilities Branch for optimal efficiency and cost-effective performance. Furthermore, many different operators need the system to track their specific projects. Most of these Facilities Specialists are not "regular" computer users, therefore, user-friendliness is of critical importance. Analyzing human factors options and presenting trade-offs is of utmost importance to ensure FAST will be used properly. If the user becomes frustrated with the system, the tool will no longer be useful to the operator or the Facilities Branch. Both the hardware and software configurations of FAST are examined for user-friendliness and efficiency. The ABC Company has a service contract with IBM, where all the hardware equipment is bought. Therefore, an IBM platform is assumed for FAST. However, various screen designs and workstation arrangements are examined in order to produce a safe. comfortable, reliable, and efficient system that will save the ABC Company time and money. / Master of Science

Computer graphics is an important tool for engineering visualization and computer aided design systems. The use of this tool to create graphical user interfaces (GUIs) for engineering applications is growing dramatically owing to the almost real-time response to creative thinking which allows engineers to quickly visualize many potential solutions to a problem. This thesis describes the creation of a GUI for a software system which is capable of predicting the surface temperatures generated at the contact between two sliding bodies. This GUI uses the ISO standard PHIGS for 3D graphics support. The use of PHIGS and the standard programming language C renders this system device-independent and hence, portable. Although PHIGS supports the creation of graphics-based engineering applications, many basic functions required for a GUI (e.g. functions for menus, templates, etc.) need to be created from scratch. During the creation of the GUI described in this thesis, special attention was paid to functions which could be created as re-usable, high-level functions. These functions can be made available to other programmers who wish to create similar GUIs for other engineering applications. The design and creation of these high-level functions and the use of these high-level functions in the creation of the GUI for the surface temperature prediction software are described in this thesis. / Master of Science

The user interface for a proposed alternative emergency service was conceived and designed for a standard touch-tone telephone. The service would allow a user to activate an automated, pre-recorded message containing information to aid emergency responders. The user must only press a few specified keys on the telephone key-pad, avoiding the need for verbal interaction with a dispatcher. The interface was designed in terms of providing the necessary instructions for activation and considering various input strategies and feedback. Icons, written instructions, and voice feedback were employed in the development of a successful and effective interface between the user and the system. Because the system is expected to attract elderly users and families with young children, the performance and attitudes of these two age groups in regard to a system prototype were examined to determine if the interface was suitable. A two and eight second initial system response time were imposed upon users to determine any effect these delays might have on user response time, error rate, and subjective attitudes. Additionally, a secondary task, designed to increase cognitive loading was employed to determine if the system is usable while the user is engaged in a dual-task environment. The dependent variables used to gauge the effects of the manipulated variables include the objective measures of user response time and error rate and subjective questionnaire responses. The results of the study indicate that the elderly adults and young children were able to activate the system successfully. System response time and cognitive loading had no significant effect on user performance or subjective attitudes. Distinct practice effects were observed. Attitude scales indicated satisfaction with the service and its interface. Finally, a significant effect of age was observed on average user response time, with the elderly activating the system quicker than the children. / Master of Science

Much of the hypermedia literature instructs developers to "Use a map to prevent users from becoming lost." However, there is very little empirical evidence that maps are effective. In addition, no one has examined how to design the maps to make them most helpful to the users. This research evaluates both issues for information retrieval tasks with a fairly small hypermedia application (about 175 nodes). This study evaluates the overall effectiveness of maps by comparing the subjects' performance using hypermedia without a map to performance with one of four maps. Then, it reveals the relative effectiveness of the different types of maps by comparing the results of the subjects' performance with four variations of a map. In addition, this research evaluates (1) the effects of the experimental conditions on the subjects' mental models of the application and (2) the effects of the subjects' spatial abilities on their performance with hypermedia. The results reveal that there is generally no difference between the subjects' performance with a map and performance without a map. In addition, users who had to navigate using the links within the application rather than selecting nodes from the map (using a "passive" map) viewed more extra nodes, but spent less time on each node and completed the tasks in less time than those who could select nodes directly from the map (using an "active" map). However, many of the subjects using the passive map would have preferred to use an active map. Also, subjects who always had a map available to them (using a "present" map) performed as well as subjects who had to call up a map to use it (a "called" map). In addition, there is no difference in the accuracy of the subjects' mental models. All the subjects understood the application fairly well. A few of the spatial abilities test results are correlated with performance, and all of significant correlations indicate that higher spatial abilities leads to improved performance with hypermedia. It is believed that the lack of differences among the conditions is due to a number of factors, including the simplicity of the application the subjects used and the tasks they performed. / Master of Science

This thesis presents Taskmaster.2, a graphical environment for interactive task specification, execution and monitoring. Problem solving in the Taskmaster environment can be accomplished with top-down programming, bottom-up programming, or a mixture of the two. The use of top-down programming permits the user to start with a high level task and refine this task into successively lower level subtasks until, at the lowest level, each subtasks represents a software tool. Bottom-up programming is accomplished by beginning with the lowest level subtasks, software tools, and then combining these tools into successively higher level subtasks until, at the highest level, the high level subtask represents the original problem task. These programming methods provide the user with abstraction capabilities. Another abstraction capability within the Taskmaster.2 environment is the network tools. The user creates network tools by selecting several software tools that, combined, provide a certain functionality. These network tools can then be reused in solving other problem tasks. In fact, these tools appear no different to the user than the low level software tools: they are both single indivisible units. Providing complete abstraction capabilities, i.e., mixing programming styles (top-down and bottom-up) and network tools, maintains the consistency of the Taskmaster.2 environment. This makes the environment an easy one to learn, as well as remember. / Master of Science

User interface design and development for ubiquitous software applications is challenged by the presence of varying contexts. Context comprises of user'­s computing platform, the environment in which the user is interacting with the application and user characteristics which comprise of user's behavior during interaction and user preferences for interface display and interaction. We present a framework for adaptive user interface generation where adaptation occurs when context changes. This framework introduces three new concepts. First, formalization for representing context is introduced. Our design of context specification is unique since it reflects the association of context with level and nature of user interface adaptation. Secondly, user interface generation life cycle is studied and we define a context model on top of task model to introduce the contextual conditions into user interface generation process. Using the context model, user interface designer can specify contextual requirements and its effect on the user interface. Third, context aware adaptation of user interfaces is achieved by mapping context specifications to various levels of user interface generation life cycle. We designed a specification language called rule specification using which the user interface designer can specify the mapping. With the new design of context representation, context model, and rule specification, we demonstrate how changes in contexts adapts task model which in turn adapts the user interface. / Master of Science

[EN] Considering the importance of games and new technologies for learning, in this thesis, two different systems that use Natural User Interfaces (NUI) for learning about a period of history were designed and developed. One of these systems uses autostereoscopic visualization, which lets the children see themselves as a background in the game, and that renders the elements with 3D sensation without the need for wearing special glasses or other devices. The other system uses frontal projection over a large-size tabletop display for visualization. The two systems have been developed from scratch. A total of five studies were carried out to determine the efficacy of games with NUI interaction with regard to acquiring knowledge, ease of use, satisfaction, fun and engagement, and their influence on children. In the first study, a comparison of the autostereoscopic system with the frontal projected system was carried out. 162 children from 8 to 11 years old participated in the study. We observed that the different characteristics of the systems did not influence the children's acquired knowledge, engagement, or satisfaction; we also observed that the systems are specially suitable for boys and older children (9-11 years old). The children had the depth perception with the autostereoscopic system. The children considered the two systems easy to use. However, they found the frontal projection to be easier to use. A second study was performed to determine the mode in which the children learn more about the topic of the game. The two modes were the collaborative mode, where the children played with the game in pairs; and the individual mode, where the children played with the game solo. 46 children from 7 to 10 years old participated in this study. We observed that there were statistically significant differences between playing with the game in the two modes. The children who played with the game in pairs in the collaborative mode got better knowledge scores than children who played with the game individually. A third study comparing traditional learning with a collaborative learning method (in pairs and in large groups) using the game was carried out. 100 children from 8 to 10 years old participated in this study. The results are in line with the second study. The children obtained higher score when collaborated in large groups or in pairs than attending to a traditional class. There were no statistically significant differences between playing in large groups and playing in pairs. For personalized learning, a Free Learning Itinerary has been included, where the children can decide how to direct the flow of their own learning process. For comparison, a Linear Learning Itinerary has also been included, where the children follow a determined learning flow. A fourth study to compare the two different learning itineraries was carried out. 29 children from 8 to 9 years old participated in this fourth study. The results showed that there were no statistically significant differences between the two learning itineraries. Regarding the online formative assessment and multiple-choice questions, there is usually a question and several possible answers in questionnaires of this kind in which the student must select only one answer. It is very common for the answers to be just text. However, images could also be used. We have carried out a fifth study to determine if an added image that represents/defines an object helps the children to choose the correct answer. 94 children from 7 to 8 years old participated in the study. The children who filled out the questionnaires with imaged obtained higher score than the children who filled out the text-only questionnaire. No statistically significant differences were found between the two questionnaire types with images. The results from the studies suggest that games of this kind could be appropriate educational games, and that autostereoscopy is a technology to exploit in their development. / [ES] Teniendo en cuenta la importancia de los juegos y las nuevas tecnologías en el aprendizaje, en esta tesis se han diseñado y desarrollado dos sistemas diferentes que utilizan interfaces de usuario naturales (NUI) para aprender los periodos de la historia. Uno de estos sistemas utiliza visión autoestereoscópica, la cual permite a los niños verse a ellos mismos dentro del juego y muestra los elementos del juego en 3D sin necesidad de llevar gafas especiales u otros dispositivos. El otro sistema utiliza proyección frontal como método de visualización. Los dos sistemas han sido desarrollados desde cero. Se han llevado a cabo un total de cinco estudios para determinar la eficacia de los juegos con NUI en cuanto al aprendizaje, facilidad de uso, satisfacción, diversión y su influencia en los niños. En el primer estudio, se ha comparado el sistema autoestereoscópico con el sistema de proyección frontal. Un total de 162 niños de 8 a 11 años han participado en este estudio. Observamos que las diferentes características de los sistemas no han influido en el aprendizaje, en la usabilidad o en la satisfacción; también observamos que los sistemas son especialmente apropiados para chicos y niños mayores (de 9 a 11 años). Los niños tienen percepción de profundidad con el sistema autoestereoscópico. Los niños consideraron los dos sistemas fáciles de usar. Sin embargo, encontraron el sistema de proyección frontal más fácil de usar. En el segundo estudio, se determina el modo con el que los niños pueden aprender en mayor medida el tema del juego. Los dos modos comparados han sido el modo colaborativo, en el que los niños jugaban por parejas; y el modo individual, en el que los niños jugaban solos. 46 niños de 7 a 10 años han participado en este estudio. Observamos que existen diferencias estadísticas significativas entre jugar al juego de un modo o de otro. Los niños que jugaron al juego en parejas en el modo colaborativo obtuvieron un mejor resultado que los niños que jugaron al juego en el modo individual. El tercer estudio compara el aprendizaje tradicional con el aprendizaje colaborativo (en parejas y en grupos grandes) utilizando el juego desarrollado. 100 niños de 8 a 10 años han participado en este estudio. Los resultados son similares al segundo estudio. Los niños obtuvieron una mejor puntuación jugando en colaboración que en el método tradicional en clase. No hubo diferencias estadísticas significativas entre jugar en grupos grandes y jugar en parejas. Teniendo en cuenta el aprendizaje personalizado se ha incluido un itinerario libre de aprendizaje, en el cual los niños pueden elegir cómo quieren dirigir su propio proceso de aprendizaje. A modo de comparación, se ha incluido también un itinerario lineal de aprendizaje, donde los niños siguen un flujo predeterminado. En este cuarto estudio han participado 29 niños de 8 a 9 años. Los resultados han mostrado que no hubo diferencias estadísticas significativas entre los dos itinerarios de aprendizaje. En cuanto a la evaluación online con preguntas de test, normalmente, hay una pregunta y varias opciones de respuesta, donde se debe seleccionar solo una de ellas. Es muy común que la respuesta esté formada únicamente por texto. Sin embargo, también se pueden utilizar imágenes. En este quinto estudio se ha llevado a cabo una comparación para determinar si las imágenes que representan las respuestas son de ayuda para elegir la correcta. 94 niños de 7 a 8 años han participado en este estudio. Los niños que rellenaron los cuestionarios con imágenes obtuvieron una mejor puntuación que los niños que rellenaron los cuestionarios en los que solo había texto. No se encontraron diferencias estadísticas significativas entre los dos tipos de cuestionarios con imágenes. Los resultados de estos estudios sugieren que los juegos de este tipo podrían ser apropiados para utilizarlos como juegos educativos, y que la autoestereoscopía es una te / [CA] Tenint en compte la importància dels jocs i les noves tecnologies en l'aprenentatge, en aquesta tesi s'han dissenyat i desenvolupat dos sistemes diferents que utilitzen interfícies naturals d'usuari per aprendre els períodes de la història. Un d'aquests sistemes utilitza visió autoestereoscòpica, la qual permet als xiquets veure's a ells mateixos dins del joc i mostra els elements del joc en 3D sense necessitat de portar ulleres especials o altres dispositius. L'altre sistema utilitza projecció frontal com a mètode de visualització. Els dos sistemes han sigut desenvolupats des de zero. S'han dut a terme un total de cinc estudis per a determinar l'eficàcia dels jocs amb interfícies d'usuari naturals quant a l'aprenentatge, facilitat d'ús, satisfacció, diversió i la seua influència en els xiquets. En el primer estudi, s'ha comparat el sistema autoestereoscòpic amb el sistema de projecció frontal. 162 xiquets de 8 a 11 anys han participat en aquest estudi. Pels resultats, observem que les diferents característiques dels sistemes no han influït en l'aprenentatge, en la usabilitat o en la satisfacció; també observem que els sistemes són especialment apropiats per a xics i xiquets majors (de 9 a 11 anys). Els xiquets tenen percepció de profunditat amb el sistema autoestereoscòpic. Els xiquets van considerar els dos sistemes fàcils d'usar. No obstant açò, van trobar el sistema de projecció frontal més fàcil d'usar. En el segon estudi es determina la manera amb el qual els xiquets poden aprendre en major mesura el tema del joc. Les dues maneres comparades han sigut la manera col·laborativa, en la qual els xiquets jugaven per parelles; i la manera individual, en la qual els xiquets jugaven sols. 46 xiquets de 7 a 10 anys han participat en aquest estudi. Pels resultats, observem que existeixen diferències estadístiques significatives entre jugar al joc d'una manera o d'una altra. Els xiquets que van jugar al joc en parelles en la manera col·laborativa van obtindre un millor resultat que els xiquets que van jugar al joc en la manera individual. El tercer estudi compara l'aprenentatge tradicional amb l'aprenentatge col·laboratiu (en parelles i en grups grans). 100 xiquets de 8 a 10 anys ha participat en aquest estudi. Els resultats són similars al segon. Els xiquets van obtindre una millor puntuació jugant en col·laboració que en el mètode tradicional en classe. No va haver-hi diferències estadístiques significatives entre jugar en grups grans i jugar en parelles. Tenint en compte l'aprenentatge personalitzat s'ha inclòs un itinerari lliure d'aprenentatge, en el qual els xiquets poden triar com volen dirigir el seu propi procés d'aprenentatge. A manera de comparació, s'ha inclòs també un itinerari lineal d'aprenentatge, on els xiquets segueixen un flux predeterminat. En aquest quart estudi han participat 29 xiquets de 8 a 9 anys. Els resultats han mostrat que no va haver-hi diferències estadístiques significatives entre els dos itineraris d'aprenentatge. Quant a l'avaluació online amb preguntes de test, normalment, hi ha una pregunta i diverses opcions de resposta, on s'ha de seleccionar solament una d'elles. És molt comú que la resposta estiga formada únicament per text. No obstant açò, també es poden utilitzar imatges. En aquest cinquè estudi s'ha dut a terme una comparació per a determinar si les imatges que representen les respostes són d'ajuda per a triar la correcta. 94 xiquets de 7 a 8 anys han participat en aquest estudi. Els xiquets que van emplenar els qüestionaris amb imatges van obtindre una millor puntuació que els xiquets que van emplenar els qüestionaris en els quals solament hi havia text. No es van trobar diferències estadístiques significatives entre els dos tipus de qüestionaris amb imatges. Els resultats d'aquests estudis suggereixen que els jocs d'aquest tipus podrien ser apropiats per a utilitzar-los com a jocs educatius, i que l'autoestereoscòpia és / Martín San José, JF. (2015). USING NATURAL USER INTERFACES TO SUPPORT LEARNING ENVIRONMENTS [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/55845

System control—the issuing of commands—is a critical, but largely unexplored task in 3D user interfaces (3DUIs) for immersive virtual environments (IVEs). System control techniques are normally encompassed by complex interfaces that define how these interaction techniques fit together, which we call system control interfaces (SCIs). Creating a testbed to evaluate these SCIs would be beneficial to researchers and would lead to guidelines for choosing a SCI for particular application scenarios. Unfortunately, a major problem in creating such a testbed is the lack of a standard task sequence—the order of operations in a system control task. In this research, we identify various task sequences, such as the Action-Object and Object- Action task sequences, and evaluate the effects that these sequences have on usability, in hopes of establishing a standard task sequence. Two studies were used to estimate the cognitive effort induced by task sequences and, hence, the effects that these sequences have on user performance. We found that sequences similar to the Object-Action task sequence induce less cognitive time than sequences similar to the Action-Object task sequence. A longitudinal study was then used to analyze user preferences for task sequences as novices became experienced users with using an interior design application. We found that novices and experienced users alike prefer sequences like the Object-Action over sequences like the Action-Object task sequence. / Master of Science