BRIDGE: uma ferramenta para o Design de Interfaces de Usu��rio baseada em especifica����es IMML

With hardware and software technologies advance, it s also happenning modifications in the development models of computational systems. New methodologies for user interface specification are being created with user interface description languages (UIDL). The UIDLs are a way to have a precise description in a language with more abstraction and independent of how will be implemented. A great problem is that even using these nowadays methodologies, we still have a big distance between the UIDLs and its design, what means, the distance between abstract and concrete. The tool BRIDGE (Interface Design Generator Environment) was created with the intention of being a linking bridge between a specification language (the Interactive Message Modeling Language IMML) and its implementation in Java, linking the abstract (specification) to the concrete (implementation). IMML is a language based on models, that allows the designer works in distinct abstraction levels, being each model a distinct abstraction level. IMML is a XML language, that uses the Semiotic Engineering concepts, that deals the computational system, with the user interface and its elements like a metacommunicative artifact, where these elements must to transmit a message to the user about what task must to be realized and the way to reach this goal. With BRIDGE, we intend to supply a lot of support to the design task, being the user interface prototipation the greater of them. BRIDGE allows the design becomes easier and more intuitive coming from an interface specification language

Gera����o de interfaces de usu��rio de sistemas Web para m��ltiplos dispositivos com o uso de componentes de IU

This work presents an User Interface (UI) prototypes generation process to the softwares that has a Web browser as a plataform. This process uses UI components more complex than HTML elements. To described this components more complex this work suggest to use the XICL (eXtensinble User Interface Components Language). XICL is a language, based on XML syntax, to describe UI Components and IUs. XICL promotes extensibility and reusability in the User Interface development process. We have developed two compiler. The first one compiles IMML (Interactive Message Modeling Language) code and generates XICL code. The second one compiles XICL code and generates DHTML code

Interfaces culturais de Mallarm�� �� World Wide Web

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Usabilidade na web: o usu��rio como agente-facilitador no desenvolvimento de interfaces de home pages

P��s-gradua����o em Design - FAAC

Online Shopping Websites: An Evaluation of User Experience and Interface Ergonomic Criteria from the Perspective of Older Users

This paper presents a user experience evaluation of two online shopping websites from the perspective of older users (those aged 50 and older). Two online shopping websites were evaluated using methodological procedures established in prior research [1]. The methodology consists of four steps: (1) heuristic interface evaluation using an ergonomic criteria checklist, (2) online identification and experience questionnaire, (3) evaluation of user experience and interface interaction, and (4) satisfaction questionnaire. Results of the study revealed the analyzed websites are not suitable for older users, who find it difficult to interact with these interfaces.

Ergonomics and interfaces of traditional information systems: packaging

The contemporary world is characterized, among other factors, by the influence of the new computer information systems on the behavior of individuals. However, traditional information systems still have interaction problems with users. The aim of this study was to determine whether the interaction aspects between user versus traditional information systems (particularly the graphics) have been fully studied. To do so, the ergonomic aspects and usability of such systems were reviewed, with emphasis on the problems of visibility, legibility and readability. From that criteria, the evolution of ergonomic studies of information systems was reviewed (bibliometrics technique); and examples of ergonomic and usability problems in packaging were demonstrated (case study). The results confirm that traditional information systems still have problems of interaction between human X system, hindering the effective perception of information.

Interfaces de not��cias t��teis em conte��dos gamificados contempor��neos

The construction methods of information lean on in variable models in the contemporary, especially by the diversity of languages and platforms offered. Among the innovations we find a growth of the gamification effect in the representation or reinforcement of the news, seizing the moment entertainment to increase user engagement. This research presents, from a case study published by The New York Times on the information complement referring to the World Cup Brazil 2014, studies of the importance of the interface in the broadcasting of informative contents, especially in a society where the tactile sensation is growing.

Desarrollo de interfaces de usuario para una herramienta de telecontrol y automatizaci��n industrial

[ES] Este proyecto de fin de carrera aborda la actualizaci��n y refactorizaci��n de la aplicaci��n Hecaton. Esta aplicaci��n permite la monitorizaci��n y actuaci��n en instalaciones industriales de manera remota a trav��s de un interfaz web. Para ello hace uso de sensores y actuadores que, conectados a trav��s de un equipo de adquisici��n de datos a un sistema inform��tico servidor, permiten obtener, manipular y almacenar los datos y eventos recibidos. Hecaton ha sido desarrollado enteramente utilizando software libre. Adem��s, el sistema permite ser personalizado, lo que posibilita su uso en todo tipo de escenarios, siendo el usuario qui��n define las reglas de funcionamiento. Este trabajo se trata del cuarto ciclo de desarrollo, pues la aplicaci��n ha sido crea y ampliada en otros tres proyectos. En este ��ltimo desarrollo se han actualizado las tecnolog��as y herramientas que forman parte de la aplicaci��n. Se ha puesto especial ��nfasis en el redise��o de la interfaz web, adoptando el uso de las ��ltimas tecnolog��as web que permiten un funcionamiento din��mico de la misma. Por otro lado se han corregido algunos errores de dise��o e introducido el uso de nuevas herramientas para la gesti��n del proyecto software. Se trata por lo tanto de un ejercicio de refactorizaci��n software donde se ha puesto especial atenci��n en conseguir un proyecto actualizado y que utilice metodolog��as de desarrollo actuales y que posibilite que sea actualizado en un futuro.

Brain-Computer Interfaces for augmented communication: Asynchronous and adaptive algorithms and evaluation with end users

This thesis aimed at addressing some of the issues that, at the state of the art, avoid the P300-based brain computer interface (BCI) systems to move from research laboratories to end users��� home. An innovative asynchronous classifier has been defined and validated. It relies on the introduction of a set of thresholds in the classifier, and such thresholds have been assessed considering the distributions of score values relating to target, non-target stimuli and epochs of voluntary no-control. With the asynchronous classifier, a P300-based BCI system can adapt its speed to the current state of the user and can automatically suspend the control when the user diverts his attention from the stimulation interface. Since EEG signals are non-stationary and show inherent variability, in order to make long-term use of BCI possible, it is important to track changes in ongoing EEG activity and to adapt BCI model parameters accordingly. To this aim, the asynchronous classifier has been subsequently improved by introducing a self-calibration algorithm for the continuous and unsupervised recalibration of the subjective control parameters. Finally an index for the online monitoring of the EEG quality has been defined and validated in order to detect potential problems and system failures. This thesis ends with the description of a translational work involving end users (people with amyotrophic lateral sclerosis-ALS). Focusing on the concepts of the user centered design approach, the phases relating to the design, the development and the validation of an innovative assistive device have been described. The proposed assistive technology (AT) has been specifically designed to meet the needs of people with ALS during the different phases of the disease (i.e. the degree of motor abilities impairment). Indeed, the AT can be accessed with several input devices either conventional (mouse, touchscreen) or alterative (switches, headtracker) up to a P300-based BCI.

Innovative Man Machine Interfaces In Aeronautics

The research activity focused on the study, design and evaluation of innovative human-machine interfaces based on virtual three-dimensional environments. It is based on the brain electrical activities recorded in real time through the electrical impulses emitted by the brain waves of the user. The achieved target is to identify and sort in real time the different brain states and adapt the interface and/or stimuli to the corresponding emotional state of the user. The setup of an experimental facility based on an innovative experimental methodology for ���man in the loop" simulation was established. It allowed involving during pilot training in virtually simulated flights, both pilot and flight examiner, in order to compare the subjective evaluations of this latter to the objective measurements of the brain activity of the pilot. This was done recording all the relevant information versus a time-line. Different combinations of emotional intensities obtained, led to an evaluation of the current situational awareness of the user. These results have a great implication in the current training methodology of the pilots, and its use could be extended as a tool that can improve the evaluation of a pilot/crew performance in interacting with the aircraft when performing tasks and procedures, especially in critical situations. This research also resulted in the design of an interface that adapts the control of the machine to the situation awareness of the user. The new concept worked on, aimed at improving the efficiency between a user and the interface, and gaining capacity by reducing the user���s workload and hence improving the system overall safety. This innovative research combining emotions measured through electroencephalography resulted in a human-machine interface that would have three aeronautical related applications: ��� An evaluation tool during the pilot training; ��� An input for cockpit environment; ��� An adaptation tool of the cockpit automation.

Organic Interfaces; or, How Human Beings Augment Their Digital Devices

It is a central premise of the advertising campaigns for nearly all digital communication devices that buying them augments the user: they give us a larger, better memory; make us more ���creative��� and ���productive���; and/or empower us to access whatever information we desire from wherever we happen to be. This study is about how recent popular cinema represents the failure of these technological devices to inspire the enchantment that they once did and opens the question of what is causing this failure. Using examples from the James Bond films, the essay analyzes the ways in which human users are frequently represented as the media connecting and augmenting digital devices and NOT the reverse. It makes use of the debates about the ways in which our subjectivity is itself a networked phenomenon and the extended mind debate from the philosophy of mind. It will prove (1) that this represents an important counter-narrative to the technophilic optimism about augmentation that pervades contemporary advertising, consumer culture, and educational debates; and (2) that this particular discourse of augmentation is really about technological advances and not advances in human capacity.

Assessing Electromyographic Interfaces

Electronic apppliances are increasingly a part of our everyday lives. In particular, mobile devices, with their reduced dimensions with power rivaling desktop computers, have substantially augmented our communication abilities offering instant availability, anywhere, to everyone. These devices have become essential for human communication but also include a more comprehensive tool set to support productivity and leisure applications. However, the many applications commonly available are not adapted to people with special needs. Rather, most popular devices are targeted at teenagers or young adults with excellent eyesight and coordination. What is worse, most of the commonly used assistive control interfaces are not available in a mobile environment where user's position, accommodation and capacities can vary even widely. To try and address people with special needs new approaches and techniques are sorely needed. This paper presents a control interface to allow tetraplegic users to interact with electronic devices. Our method uses myographic information (Electromyography or EMG) collected from residually controlled body areas. User evaluations validate electromyography as a daily wearable interface. In particular our results show that EMG can be used even in mobility contexts.

IDT-3D: Identification and tracking in controlled environments using a 3D unified user interface

Identification and tracking of objects in specific environments such as harbors or security areas is a matter of great importance nowadays. With this purpose, numerous systems based on different technologies have been developed, resulting in a great amount of gathered data displayed through a variety of interfaces. Such amount of information has to be evaluated by human operators in order to take the correct decisions, sometimes under highly critical situations demanding both speed and accuracy. In order to face this problem we describe IDT-3D, a platform for identification and tracking of vessels in a harbour environment able to represent fused information in real time using a Virtual Reality application. The effectiveness of using IDT-3D as an integrated surveillance system is currently under evaluation. Preliminary results point to a significant decrease in the times of reaction and decision making of operators facing up a critical situation. Although the current application focus of IDT-3D is quite specific, the results of this research could be extended to the identification and tracking of targets in other controlled environments of interest as coastlines, borders or even urban areas.

User-centric need-driven affect modeling for spoken conversational agents: design and evaluation

It is easy to get frustrated at spoken conversational agents (SCAs), perhaps because they seem to be callous. By and large, the quality of human-computer interaction is affected due to the inability of the SCAs to recognise and adapt to user emotional state. Now with the mass appeal of artificially-mediated communication, there has been an increasing need for SCAs to be socially and emotionally intelligent, that is, to infer and adapt to their human interlocutors��� emotions on the fly, in order to ascertain an affective, empathetic and naturalistic interaction. An enhanced quality of interaction would reduce users��� frustrations and consequently increase their satisfactions. These reasons have motivated the development of SCAs towards including socio-emotional elements, turning them into affective and socially-sensitive interfaces. One barrier to the creation of such interfaces has been the lack of methods for modelling emotions in a task-independent environment. Most emotion models for spoken dialog systems are task-dependent and thus cannot be used ���as-is��� in different applications. This Thesis focuses on improving this, in which it concerns computational modeling of emotion, personality and their interrelationship for task-independent autonomous SCAs. The generation of emotion is driven by needs, inspired by human���s motivational systems. The work in this Thesis is organised in three stages, each one with its own contribution. The first stage involved defining, integrating and quantifying the psychological-based motivational and emotional models sourced from. Later these were transformed into a computational model by implementing them into software entities. The computational model was then incorporated and put to test with an existing SCA host, a HiFi-control agent. The second stage concerned automatic prediction of affect, which has been the main challenge towards the greater aim of infusing social intelligence into the HiFi agent. In recent years, studies on affect detection from voice have moved on to using realistic, non-acted data, which is subtler. However, it is more challenging to perceive subtler emotions and this is demonstrated in tasks such as labelling and machine prediction. In this stage, we attempted to address part of this challenge by considering the roles of user satisfaction ratings and conversational/dialog features as the respective target and predictors in discriminating contentment and frustration, two types of emotions that are known to be prevalent within spoken human-computer interaction. The final stage concerned the evaluation of the emotional model through the HiFi agent. A series of user studies with 70 subjects were conducted in a real-time environment, each in a different phase and with its own conditions. All the studies involved the comparisons between the baseline non-modified and the modified agent. The findings have gone some way towards enhancing our understanding of the utility of emotion in spoken dialog systems in several ways; first, an SCA should not express its emotions blindly, albeit positive. Rather, it should adapt its emotions to user states. Second, low performance in an SCA may be compensated by the exploitation of emotion. Third, the expression of emotion through the exploitation of prosody could better improve users��� perceptions of an SCA compared to exploiting emotions through just lexical contents. Taken together, these findings not only support the success of the emotional model, but also provide substantial evidences with respect to the benefits of adding emotion in an SCA, especially in mitigating users��� frustrations and ultimately improving their satisfactions. Resumen Es relativamente f��cil experimentar cierta frustraci��n al interaccionar con agentes conversacionales (Spoken Conversational Agents, SCA), a menudo porque parecen ser un poco insensibles. En general, la calidad de la interacci��n persona-agente se ve en cierto modo afectada por la incapacidad de los SCAs para identificar y adaptarse al estado emocional de sus usuarios. Actualmente, y debido al creciente atractivo e inter��s de dichos agentes, surge la necesidad de hacer de los SCAs unos seres cada vez m��s sociales y emocionalmente inteligentes, es decir, con capacidad para inferir y adaptarse a las emociones de sus interlocutores humanos sobre la marcha, de modo que la interacci��n resulte m��s afectiva, emp��tica y, en definitiva, natural. Una interacci��n mejorada en este sentido permitir��a reducir la posible frustraci��n de los usuarios y, en consecuencia, mejorar el nivel de satisfacci��n alcanzado por los mismos. Estos argumentos justifican y motivan el desarrollo de nuevos SCAs con capacidades socio-emocionales, dotados de interfaces afectivas y socialmente sensibles. Una de las barreras para la creaci��n de tales interfaces ha sido la falta de m��todos de modelado de emociones en entornos independientes de tarea. La mayor��a de los modelos emocionales empleados por los sistemas de di��logo hablado actuales son dependientes de tarea y, por tanto, no pueden utilizarse "tal cual" en diferentes dominios o aplicaciones. Esta tesis se centra precisamente en la mejora de este aspecto, la definici��n de modelos computacionales de las emociones, la personalidad y su interrelaci��n para SCAs aut��nomos e independientes de tarea. Inspirada en los sistemas motivacionales humanos en el ��mbito de la psicolog��a, la tesis propone un modelo de generaci��n/producci��n de la emoci��n basado en necesidades. El trabajo realizado en la presente tesis est�� organizado en tres etapas diferenciadas, cada una con su propia contribuci��n. La primera etapa incluy�� la definici��n, integraci��n y cuantificaci��n de los modelos motivacionales de partida y de los modelos emocionales derivados a partir de ��stos. Posteriormente, dichos modelos emocionales fueron plasmados en un modelo computacional mediante su implementaci��n software. Este modelo computacional fue incorporado y probado en un SCA anfitri��n ya existente, un agente con capacidad para controlar un equipo HiFi, de alta fidelidad. La segunda etapa se orient�� hacia el reconocimiento autom��tico de la emoci��n, aspecto que ha constituido el principal desaf��o en relaci��n al objetivo mayor de infundir inteligencia social en el agente HiFi. En los ��ltimos a��os, los estudios sobre reconocimiento de emociones a partir de la voz han pasado de emplear datos actuados a usar datos reales en los que la presencia u observaci��n de emociones se produce de una manera mucho m��s sutil. El reconocimiento de emociones bajo estas condiciones resulta mucho m��s complicado y esta dificultad se pone de manifiesto en tareas tales como el etiquetado y el aprendizaje autom��tico. En esta etapa, se abord�� el problema del reconocimiento de las emociones del usuario a partir de caracter��sticas o m��tricas derivadas del propio di��logo usuario-agente. Gracias a dichas m��tricas, empleadas como predictores o indicadores del grado o nivel de satisfacci��n alcanzado por el usuario, fue posible discriminar entre satisfacci��n y frustraci��n, las dos emociones prevalentes durante la interacci��n usuario-agente. La etapa final corresponde fundamentalmente a la evaluaci��n del modelo emocional por medio del agente Hifi. Con ese prop��sito se llev�� a cabo una serie de estudios con usuarios reales, 70 sujetos, interaccionando con diferentes versiones del agente Hifi en tiempo real, cada uno en una fase diferente y con sus propias caracter��sticas o capacidades emocionales. En particular, todos los estudios realizados han profundizado en la comparaci��n entre una versi��n de referencia del agente no dotada de ning��n comportamiento o caracter��stica emocional, y una versi��n del agente modificada convenientemente con el modelo emocional propuesto. Los resultados obtenidos nos han permitido comprender y valorar mejor la utilidad de las emociones en los sistemas de di��logo hablado. Dicha utilidad depende de varios aspectos. En primer lugar, un SCA no debe expresar sus emociones a ciegas o arbitrariamente, incluso aunque ��stas sean positivas. M��s bien, debe adaptar sus emociones a los diferentes estados de los usuarios. En segundo lugar, un funcionamiento relativamente pobre por parte de un SCA podr��a compensarse, en cierto modo, dotando al SCA de comportamiento y capacidades emocionales. En tercer lugar, aprovechar la prosodia como veh��culo para expresar las emociones, de manera complementaria al empleo de mensajes con un contenido emocional espec��fico tanto desde el punto de vista l��xico como sem��ntico, ayuda a mejorar la percepci��n por parte de los usuarios de un SCA. Tomados en conjunto, los resultados alcanzados no s��lo confirman el ��xito del modelo emocional, sino xv que constituyen adem��s una evidencia decisiva con respecto a los beneficios de incorporar emociones en un SCA, especialmente en cuanto a reducir el nivel de frustraci��n de los usuarios y, en ��ltima instancia, mejorar su satisfacci��n.

User Experience in Human-Technology Interaction. Communication, context and evaluation methodology

En esta Tesis se presentan dos l��neas de investigaci��n relacionadas y que contribuyen a las ��reas de Interacci��n Hombre-Tecnolog��a (o M��quina; siglas en ingl��s: HTI o HMI), ling����stica computacional y evaluaci��n de la experiencia del usuario. Las dos l��neas en cuesti��n son el dise��o y la evaluaci��n centrada en el usuario de sistemas de Interacci��n Hombre-M��quina avanzados. En la primera parte de la Tesis (Cap��tulos 2 a 4) se abordan cuestiones fundamentales del dise��o de sistemas HMI avanzados. El Cap��tulo 2 presenta una panor��mica del estado del arte de la investigaci��n en el ��mbito de los sistemas conversacionales multimodales, con la que se enmarca el trabajo de investigaci��n presentado en el resto de la Tesis. Los Cap��tulos 3 y 4 se centran en dos grandes aspectos del dise��o de sistemas HMI: un gestor del di��logo generalizado para tratar la Interacci��n Hombre-M��quina multimodal y sensible al contexto, y el uso de agentes animados personificados (ECAs) para mejorar la robustez del di��logo, respectivamente. El Cap��tulo 3, sobre gesti��n del di��logo, aborda el tratamiento de la heterogeneidad de la informaci��n proveniente de las modalidades comunicativas y de los sensores externos. En este cap��tulo se propone, en un nivel de abstracci��n alto, una arquitectura para la gesti��n del di��logo con influjos heterog��neos de informaci��n, apoy��ndose en el uso de State Chart XML. En el Cap��tulo 4 se presenta una contribuci��n a la representaci��n interna de intenciones comunicativas, y su traducci��n a secuencias de gestos a ejecutar por parte de un ECA, dise��ados espec��ficamente para mejorar la robustez en situaciones de di��logo cr��ticas que pueden surgir, por ejemplo, cuando se producen errores de entendimiento en la comunicaci��n entre el usuario humano y la m��quina. Se propone, en estas p��ginas, una extensi��n del Functional Mark-up Language definido en el marco conceptual SAIBA. Esta extensi��n permite representar actos comunicativos que realizan intenciones del emisor (la m��quina) que no se pretende sean captadas conscientemente por el receptor (el usuario humano), pero con las que se pretende influirle a ��ste e influir el curso del di��logo. Esto se consigue mediante un objeto llamado Base de Intenciones Comunicativas (en ingl��s, Communication Intention Base, o CIB). La representaci��n en el CIB de intenciones ���no claradas��� adem��s de las expl��citas permite la construcci��n de actos comunicativos que realizan simult��neamente varias intenciones comunicativas. En el Cap��tulo 4 tambi��n se describe un sistema experimental para el control remoto (simulado) de un asistente dom��tico, con autenticaci��n de locutor para dar acceso, y con un ECA en el interfaz de cada una de estas tareas. Se incluye una descripci��n de las secuencias de comportamiento verbal y no verbal de los ECAs, que fueron dise��ados espec��ficamente para determinadas situaciones con objeto de mejorar la robustez del di��logo. Los Cap��tulos 5 a 7 conforman la parte de la Tesis dedicada a la evaluaci��n. El Cap��tulo 5 repasa antecedentes relevantes en la literatura de tecnolog��as de la informaci��n en general, y de sistemas de interacci��n hablada en particular. Los principales antecedentes en el ��mbito de la evaluaci��n de la interacci��n sobre los cuales se ha desarrollado el trabajo presentado en esta Tesis son el Technology Acceptance Model (TAM), la herramienta Subjective Assessment of Speech System Interfaces (SASSI), y la Recomendaci��n P.851 de la ITU-T. En el Cap��tulo 6 se describen un marco y una metodolog��a de evaluaci��n aplicados a la experiencia del usuario con sistemas HMI multimodales. Se desarroll�� con este prop��sito un novedoso marco de evaluaci��n subjetiva de la calidad de la experiencia del usuario y su relaci��n con la aceptaci��n por parte del mismo de la tecnolog��a HMI (el nombre dado en ingl��s a este marco es Subjective Quality Evaluation Framework). En este marco se articula una estructura de clases de factores subjetivos relacionados con la satisfacci��n y aceptaci��n por parte del usuario de la tecnolog��a HMI propuesta. Esta estructura, tal y como se propone en la presente tesis, tiene dos dimensiones ortogonales. Primero se identifican tres grandes clases de par��metros relacionados con la aceptaci��n por parte del usuario: ���agradabilidad ��� (likeability: aquellos que tienen que ver con la experiencia de uso, sin entrar en valoraciones de utilidad), rechazo (los cuales s��lo pueden tener una valencia negativa) y percepci��n de utilidad. En segundo lugar, este conjunto clases se reproduce para distintos ���niveles, o focos, percepci��n del usuario���. ��stos incluyen, como m��nimo, un nivel de valoraci��n global del sistema, niveles correspondientes a las tareas a realizar y objetivos a alcanzar, y un nivel de interfaz (en los casos propuestos en esta tesis, el interfaz es un sistema de di��logo con o sin un ECA). En el Cap��tulo 7 se presenta una evaluaci��n emp��rica del sistema descrito en el Cap��tulo 4. El estudio se apoya en los mencionados antecedentes en la literatura, ampliados con par��metros para el estudio espec��fico de los agentes animados (los ECAs), la auto-evaluaci��n de las emociones de los usuarios, as�� como determinados factores de rechazo (concretamente, la preocupaci��n por la privacidad y la seguridad). Tambi��n se eval��a el marco de evaluaci��n subjetiva de la calidad propuesto en el cap��tulo anterior. Los an��lisis de factores efectuados revelan una estructura de par��metros muy cercana conceptualmente a la divisi��n de clases en utilidad-agradabilidad-rechazo propuesta en dicho marco, resultado que da cierta validez emp��rica al marco. An��lisis basados en regresiones lineales revelan estructuras de dependencias e interrelaci��n entre los par��metros subjetivos y objetivos considerados. El efecto central de mediaci��n, descrito en el Technology Acceptance Model, de la utilidad percibida sobre la relaci��n de dependencia entre la intenci��n de uso y la facilidad de uso percibida, se confirma en el estudio presentado en la presente Tesis. Adem��s, se ha encontrado que esta estructura de relaciones se fortalece, en el estudio concreto presentado en estas p��ginas, si las variables consideradas se generalizan para cubrir m��s ampliamente las categor��as de agradabilidad y utilidad contempladas en el marco de evaluaci��n subjetiva de calidad. Se ha observado, asimismo, que los factores de rechazo aparecen como un componente propio en los an��lisis de factores, y adem��s se distinguen por su comportamiento: moderan la relaci��n entre la intenci��n de uso (que es el principal indicador de la aceptaci��n del usuario) y su predictor m��s fuerte, la utilidad percibida. Se presentan tambi��n resultados de menor importancia referentes a los efectos de los ECAs sobre los interfaces de los sistemas de di��logo y sobre los par��metros de percepci��n y las valoraciones de los usuarios que juegan un papel en conformar su aceptaci��n de la tecnolog��a. A pesar de que se observa un rendimiento de la interacci��n dialogada ligeramente mejor con ECAs, las opiniones subjetivas son muy similares entre los dos grupos experimentales (uno interactuando con un sistema de di��logo con ECA, y el otro sin ECA). Entre las peque��as diferencias encontradas entre los dos grupos destacan las siguientes: en el grupo experimental sin ECA (es decir, con interfaz s��lo de voz) se observ�� un efecto m��s directo de los problemas de di��logo (por ejemplo, errores de reconocimiento) sobre la percepci��n de robustez, mientras que el grupo con ECA tuvo una respuesta emocional m��s positiva cuando se produc��an problemas. Los ECAs parecen generar inicialmente expectativas m��s elevadas en cuanto a las capacidades del sistema, y los usuarios de este grupo se declaran m��s seguros de s�� mismos en su interacci��n. Por ��ltimo, se observan algunos indicios de efectos sociales de los ECAs: la ���amigabilidad ��� percibida los ECAs estaba correlada con un incremento la preocupaci��n por la seguridad. Asimismo, los usuarios del sistema con ECAs tend��an m��s a culparse a s�� mismos, en lugar de culpar al sistema, de los problemas de di��logo que pudieran surgir, mientras que se observ�� una ligera tendencia opuesta en el caso de los usuarios del sistema con interacci��n s��lo de voz. ABSTRACT This Thesis presents two related lines of research work contributing to the general fields of Human-Technology (or Machine) Interaction (HTI, or HMI), computational linguistics, and user experience evaluation. These two lines are the design and user-focused evaluation of advanced Human-Machine (or Technology) Interaction systems. The first part of the Thesis (Chapters 2 to 4) is centred on advanced HMI system design. Chapter 2 provides a background overview of the state of research in multimodal conversational systems. This sets the stage for the research work presented in the rest of the Thesis. Chapers 3 and 4 focus on two major aspects of HMI design in detail: a generalised dialogue manager for context-aware multimodal HMI, and embodied conversational agents (ECAs, or animated agents) to improve dialogue robustness, respectively. Chapter 3, on dialogue management, deals with how to handle information heterogeneity, both from the communication modalities or from external sensors. A highly abstracted architectural contribution based on State Chart XML is proposed. Chapter 4 presents a contribution for the internal representation of communication intentions and their translation into gestural sequences for an ECA, especially designed to improve robustness in critical dialogue situations such as when miscommunication occurs. We propose an extension of the functionality of Functional Mark-up Language, as envisaged in much of the work in the SAIBA framework. Our extension allows the representation of communication acts that carry intentions that are not for the interlocutor to know of, but which are made to influence him or her as well as the flow of the dialogue itself. This is achieved through a design element we have called the Communication Intention Base. Such r pr s ntation of ���non- clar ��� int ntions allows th construction of communication acts that carry several communication intentions simultaneously. Also in Chapter 4, an experimental system is described which allows (simulated) remote control to a home automation assistant, with biometric (speaker) authentication to grant access, featuring embodied conversation agents for each of the tasks. The discussion includes a description of the behavioural sequences for the ECAs, which were designed for specific dialogue situations with particular attention given to the objective of improving dialogue robustness. Chapters 5 to 7 form the evaluation part of the Thesis. Chapter 5 reviews evaluation approaches in the literature for information technologies, as well as in particular for speech-based interaction systems, that are useful precedents to the contributions of the present Thesis. The main evaluation precedents on which the work in this Thesis has built are the Technology Acceptance Model (TAM), the Subjective Assessment of Speech System Interfaces (SASSI) tool, and ITU-T Recommendation P.851. Chapter 6 presents the author���s work in establishing an valuation framework and methodology applied to the users��� experience with multimodal HMI systems. A novel user-acceptance Subjective Quality Evaluation Framework was developed by the author specifically for this purpose. A class structure arises from two orthogonal sets of dimensions. First we identify three broad classes of parameters related with user acceptance: likeability factors (those that have to do with the experience of using the system), rejection factors (which can only have a negative valence) and perception of usefulness. Secondly, the class structure is further broken down into several ���user perception levels���; at the very least: an overall system-assessment level, task and goal-related levels, and an interface level (e.g., a dialogue system with or without an ECA). An empirical evaluation of the system described in Chapter 4 is presented in Chapter 7. The study was based on the abovementioned precedents in the literature, expanded with categories covering the inclusion of an ECA, the users��� s lf-assessed emotions, and particular rejection factors (privacy and security concerns). The Subjective Quality Evaluation Framework proposed in the previous chapter was also scrutinised. Factor analyses revealed an item structure very much related conceptually to the usefulness-likeability-rejection class division introduced above, thus giving it some empirical weight. Regression-based analysis revealed structures of dependencies, paths of interrelations, between the subjective and objective parameters considered. The central mediation effect, in the Technology Acceptance Model, of perceived usefulness on the dependency relationship of intention-to-use with perceived ease of use was confirmed in this study. Furthermore, the pattern of relationships was stronger for variables covering more broadly the likeability and usefulness categories in the Subjective Quality Evaluation Framework. Rejection factors were found to have a distinct presence as components in factor analyses, as well as distinct behaviour: they were found to moderate the relationship between intention-to-use (the main measure of user acceptance) and its strongest predictor, perceived usefulness. Insights of secondary importance are also given regarding the effect of ECAs on the interface of spoken dialogue systems and the dimensions of user perception and judgement attitude that may have a role in determining user acceptance of the technology. Despite observing slightly better performance values in the case of the system with the ECA, subjective opinions regarding both systems were, overall, very similar. Minor differences between two experimental groups (one interacting with an ECA, the other only through speech) include a more direct effect of dialogue problems (e.g., non-understandings) on perceived dialogue robustness for the voice-only interface test group, and a more positive emotional response for the ECA test group. Our findings further suggest that the ECA generates higher initial expectations, and users seem slightly more confident in their interaction with the ECA than do those without it. Finally, mild evidence of social effects of ECAs was also found: the perceived friendliness of the ECA increased security concerns, and ECA users may tend to blame themselves rather than the system when dialogue problems are encountered, while the opposite may be true for voice-only users.