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FERRARI, AMBRA. "DIGITAL HUMANITY. Do Users' Gaming Habits Affect the Perceived Human-Likeness of Virtual Agents in a Simulated Human Interaction?" Doctoral thesis, Università degli Studi di Milano-Bicocca, 2021. http://hdl.handle.net/10281/315494.
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Gli agenti virtuali sono sempre più utilizzati come mentori nelle interazioni umane simulate che formano all’utilizzo di strategie di comunicazione efficaci. Tuttavia, replicare un livello di somiglianza umana soddisfacente rimane una sfida. In particolare, l'effetto Uncanny Valley si riferisce alla spiacevole sensazione provata dall’utente che interagisce con un Agente Virtuale dall’aspetto non del tutto realistico (Seyama & Nagayama, 2007). La letteratura ha descritto diversi fattori intervenienti, comprese le caratteristiche statiche e dinamiche dell'Agente, ma anche differenze individuali nel grado di predisposizione ad antropomorfizzare un Agente (ad esempio, Epley, Waytz, & Cacioppo, 2007; Kätsyri, Förger, Mäkäräinen e Takala, 2015). Negli ultimi decenni, i videogiochi hanno rappresentato una fonte di intrattenimento per un numero crescente di persone e l'obiettivo di questa tesi è stato quello di confermare se le abitudini di gioco potessero essere considerate tra i fattori intervenienti. L'industria dei videogiochi ha guidato l'innovazione tecnologica che consente la sintesi vocale e facciale ad alta fedeltà di Agenti Virtuali in prodotti di intrattenimento. Tali tecnologie spesso non sono disponibili per i laboratori di ricerca più piccoli che fanno affidamento su risorse limitate. Pertanto, la presente tesi ha esplorato anche la possibilità di individuare elementi essenziali che non richiedono interventi costosi in termini di denaro e tempo ma che possono aumentare la percezione della qualità dell’Agente Virtuale.
Oggetto principale di questa tesi è stato ENACT (Marocco, Pacella, Dell'Aquila, & Di Ferdinando, 2015), un'interazione umana simulata online per la formazione di strategie di negoziazione. In ENACT, i partecipanti hanno cinque turni di conversazione con un agente virtuale che comunica attraverso una combinazione di quattro diverse espressioni facciali, 24 gesti e 10 diverse posture del corpo e direzioni dello sguardo. La presente tesi comprende due studi sperimentali, che esplorano l'efficacia dell’implementazione di funzionalità a basso budget negli Agenti Virtuali, i.e., battiti di ciglia casuali (blinking) e una comunicazione vocale non semantica (gibberish) che accompagni la comunicazione scritta. Due campioni, rispettivamente, di 50 e 60 partecipanti maschi, tutti di età compresa tra i 18 ei 35 anni, sono stati reclutati e preliminarmente suddivisi in giocatori abituali e non abituali in base alle loro ore di gioco settimanali medie. Una volta assegnati in modo casuale al gruppo sperimentale o di controllo, i partecipanti hanno interagito con l'Agente virtuale e hanno completato i questionari relativi alla sua valutazione e alla qualità percepita di ENACT come prodotto educativo. I risultati indicano che la semplice introduzione di battiti di ciglia in momenti casuali dell'interazione con un agente virtuale sembra influenzare moderatamente la percezione dell'utente del realismo dell’Agente. Inoltre, nei casi in cui i moderni motori vocali di sintesi vocale non sono disponibili, sembra consigliabile fare affidamento su una forma di comunicazione di solo testo per gli agenti virtuali invece di una comunicazione basata su incomprensioni. I risultati suggeriscono anche che le abitudini di gioco potrebbero avere un ruolo di mediazione nella percezione delle qualità degli agenti virtuali. Tuttavia, le abitudini di gioco potrebbero non semplicemente imporre standard più elevati ai giocatori, i quali, invece, potrebbero sperimentare la zona del "troppo reale per il comfort" in modo diverso, assegnando di conseguenza diversi standard sociali attesi e aspettative normative agli agenti virtuali con cui interagiscono. Tali risultati confermano che la percezione della somiglianza umana di un Agente è una questione complessa e dimensionale, e quindi la necessità di includere la precedente alfabetizzazione di gioco nei fattori che intervengono nella percezione della stranezza.Virtual Agents have been increasingly used as deliverers of notions in Simulated Human Interactions training effective communication strategies. Nevertheless, replicating the level of human-likeness required to "convince users (…) that a virtual human is the real thing" (Ruhland et al., 2015) remains a challenge. In particular, the Uncanny Valley effect refers to the observer's unpleasant impression of a virtual being with an almost, but not entirely, realistic human form (Seyama & Nagayama, 2007). Previous literature has described several intervening factors in the perception of uncanniness, including the Agent's static and dynamic features, but also individual differences in the degree of predisposition to anthropomorphize an Agent (e.g., Epley, Waytz, & Cacioppo, 2007; Kätsyri, Förger, Mäkäräinen, & Takala, 2015). During the last decades, video games have been representing an entertainment source for a growing number of people, and this dissertation's objective has been to confirm whether game habits might be considered among intervening factors. The video game industry has been driving technological innovation allowing for high-fidelity face and voice synthesis of Virtual Agents in Entertainment products. Such technologies are often not available to smaller research laboratories relying on limited resources. Therefore, the present dissertation has also explored the possibility of identifying "easy wins" on the short development run, essential elements that do not require expensive interventions in terms of money and time but can increase the perception of the Virtual Agent's quality. ENACT (Marocco, Pacella, Dell'Aquila, & Di Ferdinando, 2015), an online Simulated Human Interaction for the training of Negotiation strategies, has been used as the main object of this dissertation. In ENACT, trainees take five conversation turns with a Virtual Agent that communicates through a combination of four different facial expressions, 24 gestures, and ten different body postures and gaze directions. The present dissertation includes two experimental studies, exploring the effectiveness of low budget implementations of Virtual Agent’s features, i.e., random eye blinks and spoken gibberish accompanying written communication. Two samples of, respectively, 50 and 60 male participants, all aged between 18 and 35, have been recruited and preliminarily divided into habitual video game players and non-habitual video game players according to their mean weekly gameplay hours. Once randomly assigned to the experimental or control group, participants interacted with the Virtual Agent and completed the questionnaires related to its uncanniness evaluation and ENACT's perceived quality as an educational product. Results indicate that the mere introduction of eye blinks in random moments of the interaction with a Virtual Agent seems to moderately affect the user's perception of the Agents' realism. Moreover, in cases when modern text-to-speech voice engines are not available, it seems advisable to rely on a text-only form of communication for Virtual Agents instead of a gibberish-based communication. Results also suggest that video game habits might have a mediating role in the perception of Virtual Agents' qualities. Nevertheless, game habits might not simply posit higher standards to players but, instead, they might experience the "too real for comfort" zone differently, consequently assigning different expected social standards and normative expectations to Virtual Agents they interact with. Such results confirm that the perception of an Agent's human-likeness is a complex and dimensional matter, therefore including previous gaming literacy into the factors intervening in the perception of uncanniness.
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Lala, Divesh. "The design and implementation of dynamic interactive agents in virtual basketball." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199434.
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Schanche, Anders. "Human - Virtual Agent Interaction." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-17181.
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This thesis was carried out at Imagination Studios in Uppsala. IMS is a motion capture studio that alsodoes animation. Motion capture is the capturing of (generally) human motions to make 3Danimations look more realistic. In motion capture, the actors have to imagine the scene. The goal ofthis thesis is to help the motion capture actor by creating a tool that lets the actor interact with avirtual agent that represents his acting partner. Scenarios and a video sketch were created todescribe how the interaction can work. The Microsoft Kinect is used to capture the motions of theactor and recognize gestures. These gestures are then responded to by a virtual agent that isdisplayed in a 3D environment created in the Unreal Development Kit. Programming was done in C++and UnrealScript to make this solution work. Motions were recorded and applied to the virtual agentto create realistic animations that are played in response to the actor's gestures. The final product isan interactive application that can be used to immerse a person in an acting scenario.
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Trescak, Tomás. "Intelligent Generation and Control of Interactive Virtual Worlds." Doctoral thesis, Universitat Autònoma de Barcelona, 2012. http://hdl.handle.net/10803/117675.
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Esta tesis aboga por el uso de los mundos virtuales como una tecnología de futuro en el dominio de
los mundos virtuales serios, en particular en aplicaciones e-‐* (e-‐learning, e-‐commerce, e-‐
government) y en simulaciones sociales. En estas aplicaciones, el entorno virtual 3D está poblado
por un gran número de habitantes que pueden ser humanos o avatares controlados por agentes
virtuales inteligentes que se involucran en interacciones complejas con su entorno y con los demás
participantes.
Un problema importante que impide la adopción generalizada de la tecnología de mundos virtuales
en estos dominios es que, en general, los mundos virtuales son difíciles de construir y se tiene que
emplear un gran esfuerzo en el diseño del entorno virtual 3D y en la programación de los agentes
virtuales; pero es aún más difícil asegurar la validez de las interacciones de forma que se prevengan
comportamientos no permitidos.
Para abordar este problema, hemos desarrollado una solución integral que automatiza el diseño de
estos mundos virtuales y de su población. Nuestro enfoque se basa en la utilización de las
instituciones virtuales, que son mundos virtuales que regulan las interacciones de sus participantes.
El enfoque principal de esta tesis está en explicar cómo los métodos existentes de especificación
formal de las instituciones virtuales se pueden extender para traducir automáticamente la
especificación institucional en un entorno interactivo 3D utilizando el enfoque de las gramáticas de
formas (Shape Grammars) y para poblar, de forma también automática, este tipo de entornos con
agentes virtuales.
Las gramáticas de formas son una técnica visual potente para la generación de diseños 2D y 3D,
pero el trabajo realizado hasta el momento en esta área no se adecua a las características de
nuestro problema. Por lo tanto, en esta tesis hemos extendido los trabajos realizados en este
campo y hemos desarrollado el framework “Shape Grammar Interpreter”, que se ocupa de las
limitaciones de las soluciones existentes. Hemos utilizado este framework para el desarrollo del
concepto de Virtual World Grammar, que es un subconjunto de las gramáticas de formas dirigido a
la generación automática de mundos virtuales normativos. Como resultado de esta tesis, la Virtual
World Grammar ha sido formalizada e implementada en un entorno de desarrollo que no sólo
permite la generación automática de mundos virtuales normativos, sino también su
implementación independiente de la plataforma (utilizando VIXEE, la infraestructura que se ha
desarrollado como una parte importante de esta tesis).
Otra contribución de esta tesis es el desarrollo de un mecanismo de generación automática de un
gran número de agentes de software. Estos agentes son capaces de realizar interacciones
inteligentes con objetos 3D dentro del entorno. Además, estos agentes son capaces de colaborar
con avatares controlados por humanos, facilitar la resolución de sus problemas y asegurar que
todas sus acciones se adhieren de forma estricta a las normas sociales de la institución.
Para ello, hemos desarrollado un modelo general de agente virtual que permite situar a un agente
en un mundo virtual normativo, generar sus propios objetivos en función de sus necesidades
fisiológicas y psicológicas, así como generar dinámicamente los planes para satisfacer estos
objetivos mediante la especificación institucional subyacente.
Para ilustrar la utilidad de los métodos y técnicas desarrolladas en esta tesis, hemos aplicado éstas
al campo de la simulación histórica, recreando la vida de la ciudad de Uruk. Hemos mostrado cómo
nuestro enfoque permite crear un gran número de agentes diversos tanto en aspectos visuales
como de comportamiento, así como la generación dinámica de los alimentos, herramientas y otros
elementos que se utilizan para satisfacer sus objetivos, mientras actúan de forma correcta,
históricamente hablando.This thesis advocates the use of non-‐gaming virtual worlds as a significant future technology for the domain of ``serious games’’ and in particular e-‐* applications (e-‐ learning, e-‐commerce, e-‐government) and social simulations. In such systems, a 3D virtual environment is populated by a large number of inhabitants that can be either human-‐ controlled avatars or intelligent virtual agents who engage in complex interactions with their virtual environment and other participants. One significant problem that impedes wide adoption of the virtual worlds technology for these problem domains is that virtual worlds in general are difficult to build, and significant effort has to be put into designing the 3D virtual environment and programming virtual agents; but it is even harder to ensure the validity of participant so that unauthorized behavior can be prevented. To address this problem, we have developed a comprehensive technological solution that automates the design of such virtual worlds and its population with virtual agents. Our approach is based on the utilization of virtual institutions, which are virtual worlds with normative regulation of participant interactions. The key focus of the thesis is on explaining how existing methods of formal specification of virtual institutions can be extended to automatically translate the institutional specification into an interactive 3D environment using the shape grammars approach and automatically populating such environments with virtual agents. Shape grammars represent a powerful visual technique for creating procedural 2D and 3D designs, but existing work was not immediately suitable for our problem. Thus, we have extended existing work and developed the Shape Grammar Interpreter framework, which addresses the limitations of existing solutions. This framework was further utilized for developing the concept of Virtual World Grammar, which is a sub-‐set of shape grammars targeting automatic generation of normative virtual worlds. As the result of this dissertation, Virtual Worlds Grammars constitute a strong formalization and a development environment not only enabling automatic generation of normative virtual worlds, but also their platform independent deployment (using the VIXEE infrastructure that has been developed as an important part of this dissertation). Another significant contribution of this thesis is developing a mechanism of automatic population of the generated environments with large numbers of software agents, which are capable of intelligent interactions with 3D objects placed in the environment. Moreover, these agents are able to collaborate with human-‐controlled avatars, facilitate their problem-‐solving and ensure that all their actions strictly adhere to social norms of the given institution. For this purpose, we have developed a general-‐purpose virtual agent model that enables an agent to be situated within any normative virtual world, generate its own goals based on its current physiological and psychological needs, as well as to dynamically generate plans for satisfying these goals using the underlying institutional specification. To illustrate the usefulness of the developed technology, we have applied it to the domain of historical simulation, where we show how virtual world grammars and automatically generated virtual agents can be used for re-‐enacting everyday life of ancient people in one of humanity's first cities, the city of Uruk. We showed how our approach allows to create a large number of visually and behaviorally diverse agents, as well as dynamically generating food, tools and other items that they can utilize to satisfy their goals, while acting in a historically correct way.
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Lebrun, Yoann. "Architecture multi-agent pour la gestion d'objets tangibles et virtuels sur Table Interactive." Phd thesis, Université de Valenciennes et du Hainaut-Cambresis, 2012. http://tel.archives-ouvertes.fr/tel-00718624.
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Les recherches menées par le travail de thèse visent à proposer une nouvelle architecture multi-agent pour la conception d'applications sur de nouvelles plateformes de communication telles que les tables interactives. Les systèmes Multi-Agents sont utilisés depuis de nombreuses années et peuvent répondre aux problématiques de telles plateformes. Dans notre contexte, nous avons défini les interactions et les comportements d'agents hétérogènes (virtuels et tangibles), qui évoluent simultanément sur une même surface interactive.Nous avons défini une typologie des agents, utilisés dans le cadre de plateformes interactives, en fonction d'un ensemble de critères permettant d'analyser les caractéristiques logicielles et technologiques (système de capture, affichage, etc.) employées sur ces nouveaux supports. Nous proposons de modéliser les comportements élémentaires nécessaires à la description du problème (interactions éventuelles de plusieurs utilisateurs, utilisation d'objets, visualisation de l'environnement et des agents simulés, traitement des messageséchangés, etc.), lesquels sont représentés par des rôles joués simultanément par un ou plusieurs agents selon un ensemble de prérequis. La réflexion proposée a conduit à la construction d'une architecture multi-agent, laquelle a été appliquée sur la table interactive TangiSense (intégrant une technologie RFID). Nous illustrons et nous validons notre propos à l'aide d'une application, un simulateur de trafic routier.
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Vinayagamoorthy, Vinoba. "Participant responses to virtual agents in immersive virtual environments." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1445140/.
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This thesis is concerned with interaction between people and virtual humans in the context of highly immersive virtual environments (VEs). Empirical studies have shown that virtual humans (agents) with even minimal behavioural capabilities can have a significant emotional impact on participants of immersive virtual environments (IVEs) to the extent that these have been used in studies of mental health issues such as social phobia and paranoia. This thesis focuses on understanding the impact on the responses of people to the behaviour of virtual humans rather than their visual appearance. There are three main research questions addressed. First, the thesis considers what are the key nonverbal behavioural cues used to portray a specific psychological state. Second, research determines the extent to which the underlying state of a virtual human is recognisable through the display of a key set of cues inferred from the behaviour of real humans. Finally, the degree to which a perceived psychological state in a virtual human invokes responses from participants in immersive virtual environments that are similar to those observed in the physical world is considered. These research questions were investigated through four experiments. The first experiment focused on the impact of visual fidelity and behavioural complexity on participant responses by implementing a model of gaze behaviour in virtual humans. The results of the study concluded that participants expected more life-like behaviours from more visually realistic virtual humans. The second experiment investigated the detrimental effects on participant responses when interacting with virtual humans with low behavioural complexity. The third experiment investigated the differences in responses of participants to virtual humans perceived to be in varying emotional states. The emotional states of the virtual humans were portrayed using postural and facial cues. Results indicated that posture does play an important role in the portrayal of affect however the behavioural model used in the study did not fully cover the qualities of body movement associated with the emotions studied. The final experiment focused on the portrayal of affect through the quality of body movement such as the speed of gestures. The effectiveness of the virtual humans was gauged through exploring a variety of participant responses including subjective responses, objective physiological and behavioural measures. The results show that participants are affected and respond to virtual humans in a significant manner provided that an appropriate behavioural model is used.
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Lucca, Ricardo Rodrigues. "MARO : um modelo de emoções usando ontologia." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/108987.
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Este trabalho apresenta um framework que permite a programação de agentes capazes de perceberem seus próprios estados emocionais. O framework foi desenvolvido em Java com base na plataforma multi-agente Jason, estendendo a base de crenças de agentes Jason a fim de utilizar a ontologia afetiva desenvolvida. Além disso, o ambiente foi construído a partir de uma base de conhecimento que descreve rotinas em ambientes simulados. Um mecanismo de avaliação das emoções baseando-se nas anotações dos objetos foi construído apoiado por uma ontologia de preferência sobre essas anotações. Dessa forma, aplicações de entretenimento poderiam utilizar o sistema ou as bases de conhecimento apresentadas para diferentes propósitos. A criação de um mapa onde os personagens atuam, e a criação da rotina de cada personagem e suas preferências são alguns exemplos de utilizações. Para validação do framework desenvolvido, dois exemplos foram construídos. O primeiro utilizou a maior parte dos grupos afetivos da ontologia proposta, com a finalidade principal de demonstrar o modelo implementado. Já o segundo usa apenas um grupo emotivo e serve para demonstrar a utilização conjunta de todas as ontologias apresentadas.This work presents a framework built on top of the Jason platform (BORDINI et al., 2004) to allow the development of software agents that have emotional states. The framework was developed in Java and extends the belief base of Jason agents so as to use an ontology for the OCC affective model (ORTONY; COLLINS; CLORE, 1988) that has been created as part of this work. The developed belief base allows an agent to perceive its own emotions throw inferring new beliefs based on the agent’s appraisal of the state of the environment. In addition, a model of agents’ routine tasks was defined, as was a model for agents’ preferences about aspects of environment, helping automate the ascription of emotional states. Finally, in order to validate the developed framework, two applications were developed. The first demonstrates the use of various different emotions from the affective model and the second uses in a single application all the ontologies and models developed as part of this work.
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Boukhris, Mehdi. "Modélisation et évaluation de la fidélité d'un clone virtuel." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS177/document.
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L'identification des visages est primordiale lors de nos interactions sociales. Ainsi, notre comportement change suite à l'identification de la personne avec laquelle nous interagissons. De plus, les travaux en psychologie et en neurosciences ont observé que le traitement cognitif face à un visage familier diffère de celui que nous avons face à un visage inconnu.D'une autre part, les dernières techniques de rendu 3D et les dernières avancées des scans 3D ont permis la création de visages virtuels photo-réalistes modélisant des personnes réelles existantes. La tendance actuelle pour modéliser des humains virtuels est de se baser sur des techniques d'acquisition de données réelles (issues de scans et de sessions de capture de mouvement). Par conséquent, les recherches et applications en humains virtuels ont connu un intérêt croissant pour ces clones virtuels (des agents ayant un aspect familier ou du moins reconnaissable). Les clones virtuels sont donc de plus en plus répandus dans des interfaces homme-machine et dans l'industrie audio-visuelle.L'étude de la perception et de l'interaction avec des clones virtuels est donc devenue nécessaire pour appréhender la conception et l'évaluation de cette technologie. En effet, très peu d'études se sont penchées sur l'évaluation de la fidélité de ces clones virtuels. L'objectif de cette thèse consiste à explorer cet axe de recherche en examinant le processus de perception de la fidélité d'un visage virtuel, clone d'une personne réelle (que l'on connait ou non).Nos travaux répondent à plusieurs questions de recherche: Quels sont les éléments qui nous permettent d'évaluer la ressemblance du clone virtuel avec son référent? Parmi les multiples possibilités de techniques de rendu, d'animation et d'acquisition de données qu'offre l'informatique graphique, quelle est la meilleure combinaison pour assurer le plus haut degré de fidélité perçue ? L'apparence visuelle n'est cependant qu'une des composantes qui interviennent dans la reconnaissance de personnes familières. Les autres composantes comprennent ainsi l'expressivité mais aussi le traitement des connaissances que nous avons sur cette personne (par exemple sa manière particulière d'évaluer une situation émotionnelle et de l'exprimer via son visage).Nos contributions apportent des éléments de réponse à ces questions à plusieurs niveaux. Nous avons défini un cadre conceptuel identifiant les principaux concepts pertinents pour l'étude de la fidélité d'un visage virtuel. Nous avons aussi étudié l'aspect visuel de la fidélité à travers l'exploration de différentes techniques de rendu. Nous avons étudié dans une autre étape l'impact de la familiarité dans le jugement de la fidélité. Finalement, nous avons proposé un modèle informatique individuel basé sur une approche cognitive des émotions qui permet de guider l'animation expressive du clone virtuel.Ces travaux de thèse ouvrent des perspectives pour la conception et l'amélioration de clones virtuels, mais aussi plus généralement des interfaces homme-machine basées sur des agents expressifsFace identification plays a crucial role in our daily social interactions. Indeed, our behavior changes according to the identification of the person with whom we interact. Moreover, several studies in Psychology and Neurosciences have observed that our cognitive processing of familiar faces is different from the cognitive processing of unfamiliar faces.Creating photorealistic an animated human-like face of a real person is now possible thanks to recent advances in Computer Graphics and 3D scan systems. Recent rendering techniques are challenging our ability to distinguish between computer generated faces and real human faces. Besides, the current trend to model virtual humans is to involve real data collected using scans and motion capture systems. Research and applications in virtual humans have experienced a growing interest in so-called virtual clones (agents with a familiar aspect or at least recognizable). Virtual clones are therefore increasingly used in human-machine interfaces and in the audiovisual industry. Studies about the perception and interaction with virtual clones are therefore required to better understand how we should design and evaluate this kind of technology. Indeed, very few studies have tried to evaluate virtual clones' fidelity with respect to the original human (hereafter called “the referent”). The main goal of this thesis is to explore this line of research. Our work rises several research questions: What are the features of the virtual clone that enable us to evaluate the resemblance between a virtual clone and its referent? Among several possibilities of rendering, animation and data acquisition techniques offered by Computer Graphics, what is the best combination of techniques to ensure the highest level of perceived fidelity?However, visual appearance is not the only component that is involved in recognizing familiar people. The other components include facial expressiveness but also the possible knowledge that we have about the referent (e.g. his particular way of assessing an emotional situation and expressing it through his face).Our contributions provide answers to these questions at several levels. We define a conceptual framework identifying the key concepts which are relevant for the study of the fidelity of a virtual face. We explore different rendering techniques. We describe an experimental study about the impact of familiarity in the judgment of fidelity. Finally, we propose a preliminary individual computational model based on a cognitive approach of emotions that could drive the animation of the virtual clone.This work opens avenues for the design and improvement of virtual clones, and more generally for the human-machine interfaces based on expressive virtual agents
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Berkovich, Aleksandr 1979. "IVAN : Integrated Virtual Agent Network." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87189.
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Thesis (M.Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2002.Includes bibliographical references (leaves 70-71).
by Aleksandr Berkovich.
M.Eng.and S.B.
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Rimkus, Edvardas. "ALGORITMŲ INTELEKTUALAUS PROGRAMINIO AGENTO BŪSENAI ATPAŽINTI TYRIMAS." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060614_101100-19191.
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In the context of adaptive intellectual learning environment (VLE) possibility of using conceptual clustering algorithms is analyzed, trying to accomplish the ability of software agent to "feel" the changing environment and recognise the states it is in. Agent environment is understood as interface between the user of VLE and the students model, which is stored in the VLE and is constantly changing. Agents ability to "feel" is understood as agents ability to classify students, based on their knowledge level, which changes in the learning process. Using conceptual clustering algorithms found in the literature, we are trying to choose one which is most suited for the problem area, modifying it to model real data.
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Wargnier, Pierre. "Technologies d'humains virtuels dans le soin aux personnes âgées atteintes de troubles cognitifs : les expériences LOUISE et Virtual Promenade." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLEM021/document.
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Les travaux présentés dans ce manuscrit portent sur l'utilisation des humains virtuels et, plus globalement, des technologies du jeu vidéo pour améliorer le soin aux personnes âgées atteintes de troubles cognitifs. Nos travaux s'articulent autour de deux cas d'utilisation des humains virtuels : comme non-soi et comme soi. Plus spécifiquement, nous avons conçu, implémenté et évalué un agent conversationnel animé, appelé LOUISE (LOvely User Interface for Servicing Elders), ayant pour but de servir d'interface utilisateur accessible dans les dipositifs de compensation cognitives à destination des personnes âgées attenteintes de troubles cognitifs, et un dispositif de thérapie psychologique par la réalité virtuelle pour traiter les conséquences des chutes, appelé Promenade virtuelle. Ces deux projets ont été menés suivant des principes de conception participative en living lab, implicant plusieurs parties prenantes dans le processus de conception (patients, aidants et professionnels de santé)The work presented in this manuscript investigates the use of virtual huamans, and, more broadly, of video game technologies to improve the care of older adults with cognitive impairment. Our work revolved around two use cases of virtual humans: as non-self and as self. More specifically, we have designed, implemented and evaluated an embodied conversational agent, called LOUISE (LOvely User Interface for Servicing Elders), meant to serve as an accessible user interface in cognitive compensation systems for older adults with cognitive impairment, and a system for virtual reality-based psychological therapy addressing the consequences of falls, called Virtual Promenade. These two projects have been conducted according to the principles of living lab participatory design, involving several stakeholders in the design process (patients, caregivers and healthcare professionals)
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Bogdanovych, Anton. "Virtual Institutions." Electronic version, 2007. http://hdl.handle.net/2100/536.
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University of Technology, Sydney. Faculty of Information Technology.This thesis establishes Virtual Institutions as a comprehensive software engineering technology for the development of 3D Virtual Worlds that require normative regulation of participants’ interactions (such as the commercially-oriented Virtual Worlds). 3D Virtual Worlds technology currently offers somewhat unregulated environments without means to enforce norms of behavior and interaction rules on their inhabitants. Furthermore, existing methodologies for Virtual Worlds development focus primarily on the design side of the “look-and-feel” of the inhabited space. Consequently, in current 3D Virtual Worlds it is difficult to keep track of the deviant behavior of participants and to guarantee a high level of security and predictable overall behavior of the system. The Virtual Institutions Methodology proposed by this dissertation is focused on designing highly secure heterogeneous Virtual Worlds (with humans and autonomous agents participating in them), where the participants behave autonomously and make their decisions freely within the limits imposed by the set of norms of the institution. It is supported by a multilayer model and representational formalisms, and the corresponding tools that facilitate rapid development of norm-governed Virtual Worlds and offer full control over stability and security issues. An important part of the Virtual Institutions Methodology is concerned with the relationship between humans and autonomous agents. In particular, the ways to achieve human-like behavior by learning such behavior from the humans themselves are investigated. It is explained how formal description of the interaction rules together with full observation of the users’ actions help to improve the human-like believability of autonomous agents in Virtual Institutions. The thesis proposes the concept of implicit training, which enables the process of teaching autonomous agents human characteristics without any explicit training efforts required from the humans, and develops the computational support for this new learning method. The benefits of using Virtual Institutions are illustrated through applying this technology to the domain of E-Commerce. It is demonstrated that providing shoppers with a normative environment that offers immersive experience and supports important real world attributes like social interaction, location awareness, advanced visualization, collaborative shopping and impulsive purchases can improve existing practices in E-Commerce portals.
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Orwick, Ogden Sherri L. "Agent for Interactive Student Assistance: A Study of an Avatar-Based Conversational Agent's Impact on Student Engagement and Recruitment at BGSU's College of Technology." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1319804597.
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Franzén, Daniel. "A Modular API for Intelligent Virtual Agents." Thesis, Linköping University, Department of Science and Technology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8508.
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This report proposes a modular Application Programmer's Interface (API) for handling the mental layer of intelligent virtual agents for a wide range of application types, with the aim of reducing the work required to program a completely new AI engine, and describes its implementation. One of the key elements and major difficulties in its design is the need to make it general enough to suit most types of applications, while preserving its usefulness and keeping it both efficient and reliable. A sample application interfacing with the API is created to demonstrate its capabilities, various AI algorithms are looked into and their respective suitability for the API is evaluated, and some techniques are implemented as modules in the API.
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Johansson, Anja. "Modelling Expectations and Trust in Virtual Agents." Thesis, Linköping University, Department of Science and Technology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-9704.
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Computer graphics has long been the foremost area of advancement in both the gaming and the motion picture industry. Nowadays, as computer graphics is getting difficult to advance any further, other areas begin to interest the developers. One of these areas is artificial intelligence. The gaming industry has begun to create far more intelligent virtual characters that no longer are as predictable as they used to be. Mixing character animation with intelligent agents techniques results in a vastly more interesting experience for the gamer as well as for the developer.
This project focuses on introducing expectational behaviour and trust in intelligent virtual characters. The area is highly interesting as it enables a vastly more complex emotional structure for virtual agents than that of reactive, rational behaviour. Although expectations can indeed be rational, often they are not when it comes to humans. This project studies the effects of expectations on the emotional state of agents and the effect that the emotions have on the reasoning abilities and the action selection mechanism. It also examines how trust influences emotions and vice versa and how trust influences the action selection mechanism.
One of the requirements of this work is that the computations concerning the triggering of emotions have to be done in real-time. While it is possible to do off-line computations for simulations (such as is often done for the movie industry), it is not what we desire here. It is our goal to create interesting virtual characters that can be interacted with in real-time. Therefore, also expectations and trust must be calculated and managed in real-time.
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Weiner, Giocondo E. "Constructing Virtual Internet Agents to Improve Learning." NSUWorks, 2001. http://nsuworks.nova.edu/gscis_etd/914.
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There has been extensive research on the design and development of software agents. However, little has been reported about educational applications involving agents or on how users interact with them in a multimedia learning environment. Furthermore, music departments in many school districts have a real need for instructional tools that would help students learn basic principles of ethnic wind musical instruments and music elements. Currently there are few, if any, music learning programs that offer personalized instruction to students. The investigator developed two programs: An interactive multimedia panpipe program (IMPP) and the same program with a virtual Internet agent (VIA) called a virtual Internet agent program (VIAP). She tested the hypothesis that a VIA improves the quality and effectiveness of online, interactive learning programs. The IMPP and the VIAP were designed and programmed based on accepted instructional and learning theories. The pentatonic panpipe program (PPP) has been demonstrated to be an excellent vehicle for teaching basic music elements. The IMPP and VIAP contain methodology for learning how to build and play the pentatonic panpipe. In order to assess the pedagogical value of VIAP, the researcher designed and developed two interactive Internet programs, one with agents (VIA), and the other without, '(or teaching basic principles on how to build and play the Andean pentatonic panpipe. The programs introduce basic units of learning on acoustics, Andean culture, and wind instruments. These programs helped to determine the effectiveness of VIA as a teaching enhancement. Results were validated using non-standardized pretests and posttests to both the experimental and control groups. There was also a survey questionnaire covering the IMPP and the VIAP and two additional instruments, a group appraisal form and a rating sheet, for collecting data not obtained from paper-and-pencil tests. Subjects were selected randomly from a population of 42 fifth grade children, attending an elementary school. These subjects were tested and observed in a computer lab environment. There were two sets of students, 20 in the experimental group, with VIA, and 22 in the control group, without VIA.
The findings showed that agent -based technologies vastly improved the quality and effectiveness of online instructional systems. Posttest scores revealed a greater gain made by the experimental group than the control group. The difference in the mean scores was significant. Since the results varied significantly, Q < .05, among the experimental and controls, the null hypothesis was rejected (A = B) and it was concluded that the mean score of the experimental group was significantly greater than the control group. This validated the original hypothesis that the use of VIA in online interactive learning environments improves knowledge acquisition, retention, and satisfaction in an uninitiated sample group. VIAP is an interactive teaching program with virtual Internet agents that was proven to be a highly effective pedagogical tool.
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Huang, Jing. "Modèles de rendu et animation émotionnelle en 3 D." Thesis, Paris, ENST, 2013. http://www.theses.fr/2013ENST0008/document.
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L'animation et le rendu sont deux domaines de recherche importants dans l'informatique graphique. L'occlusion ambiante (OA) est un moyen très répandu pour simuler l'éclairage indirect. Nous présentons une approche rapide et facile à mettre en œuvre pour l'approximation de l'occlusion ambiante de l'espace d'affichage. On calcule l'OA pour chaque pixel en intégrant les valeurs angulaires des échantillonneurs autour de la position du pixel qui pourrait bloquer l'éclairage ambiant. Nous appliquons une méthode séparable afin de réduire la complexité du calcul. La simulation des rides expressives du visage peut être estimée sans changer l'information géométrique. Nous avons construit un modèle de rides en utilisant une technique graphique qui effectue des calculs seulement dans l'espace d'affichage. Les animations faciales sont beaucoup plus réalistes avec la présence des rides. Nous présentons une méthode de cinématique inverse rapide et facile à mettre en œuvre qui s'appuie sur un modèle masse-ressort et qui repose sur les interactions de forces entre les masses. Les interactions de forces entre les masses peuvent être vues comme un problème de minimisation de l'énergie. Elle offre une très bonne qualité visuelle en haute performance de vitesse. En se basant sur notre méthode d'IK, nous proposons un modèle de synthèse des gestes corporels expressifs intégrés dans notre plateforme d'agents conversationnels. Nous appliquons l'animation de tout le corps enrichi par l'aspect expressif. Ce système offre plus de flexibilité pour configurer la cinématique expressive directe ou indirecte. De façon globale, cette thèse présente notre travail sur le rendu et l'animation en 3DAnimation and rendering are both important research domains in computer graphics. We present a fast easy-to-implement separable approximation to screen space ambient occlusion.We evaluate AO for each pixel by integrating angular values of samplers around the pixel position which potentially block the ambient lighting.We apply a separable fashion to reduce the complexity of the evaluation. Wrinkle simulation can also be approximated without changing geometry information.We built a wrinkles model by using a modern graphics technique which performs computations only in screen space.With the help of wrinkles, the facial animation can be more realistic. Several factors have been proved, and wrinkles can help to recognize action units with a higher rate. Inverse kinematics (IK) can be used to find the hierarchical posture solutions. We present a fast and easy-to-implement locally physics-based IK method. Our method builds upon a mass-spring model and relies on force interactions between masses. Our method offers convincing visual quality results obtained with high time performance. Base on our IK method, we propose our expressive body-gestures animation synthesis model for our Embodied Conversational Agent (ECA) technology. Our implementation builds upon a full body reach model using a hybrid kinematics solution. Generated animations can be enhanced with expressive qualities.This system offers more flexibility to configure expressive Forward and Inverse Kinematics (FK and IK). It can be extended to other articulated figures. Overall, this thesis presents our work in 3D rendering and animation. Several new approaches have been proposed to improve both the quality and the speed
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Rydell, Andreas. "Multi-agent swarm control in virtual worlds." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-104977.
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Flocking birds in a virtual world through adaption of Craig Reynolds, Boids algorithm. In this paper I will demonstrate how I adapted the Boids algorithm to an already existing code to create a flocking behaviour and discuss options to the solutions. I have been given a virtual world with existing birds that is moving around based on random elements that in a way mimics flying.
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Abdullah, Bashar. "Intelligent multi-agent-based virtual gauges (IMAGES)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ38731.pdf.
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Sathi, Pratap R. "Experienced agents with attitude in a virtual marketplace." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ62280.pdf.
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Nakhal, Bilal. "Generation of communicative intentions for virtual agents in an intelligent virtual environment : application to virtual learning environment." Thesis, Brest, 2017. http://www.theses.fr/2017BRES0156/document.
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La réalité virtuelle joue un rôle majeur dans le développement de nouvelles technologies de l’éducation, et permet de développer des environnements virtuels pour l’apprentissage, dans lesquels, des agents virtuels intelligents jouent le rôle de tuteur. Ces agents sont censés aider les utilisateurs humains à apprendre et appliquer des procédures ayant des objectifs d’apprentissage prédéfini dans différents domaines. Nous travaillons sur la construction d’un système temps-réel capable d’entamer une interaction naturelle avec un utilisateur dans un Environnement d’Apprentissage Virtuel (EAV). Afin d’implémenter ce modèle, nous proposons d’utiliser MASCARET (Multi-Agent System for Collaborative, Adaptive & Realistic Environments for Training) comme modèle d’Environnement Virtuel Intelligent (EVI) afin de représenter la base de connaissances des agents, et de modéliser la sémantique de l’environnement virtuel et des activités des utilisateurs. Afin de formaliser l’intention des agents, nous implémentons un module cognitif dans MASCARET inspiré par l’architecture BDI (Belief-Desire-Intention) qui nous permet de générer des intentions de haut-niveau pour les agents. Dans notre modèle, ces agents sont représentés par des Agents Conversationnels Animés (ACA), qui sont basés sur la plateforme SAIBA (Situation, Agent, Intention, Behavior, Animation). Les agents conversationnels de l’environnement ont des intentions communicatives qui sont transmises à l’utilisateur via des canaux de communication naturels, notamment les actes communicatifs et les comportements verbaux et non-verbaux. Afin d’évaluer notre modèle, nous l’implémentons dans un scénario pédagogique concret pour l’apprentissage des procédures d’analyse de sang dans un laboratoire biomédical. Nous utilisons cette application afin de réaliser une expérimentation et une étude pour valider les propositions de notre modèle. L’hypothèse de notre étude est de supposer que la présence d’un ACA dans un Environnement Virtuel (EV) améliore la performance du processus d’apprentissage (ou qu’au moins, ça ne le dégrade pas) dans le contexte de l’apprentissage d’une procédure spécifique. La performance de l’utilisateur est représentée par le temps requis pour l’exécution de la procédure, le nombre d’erreurs commises et le nombre de demande d’assistance. Nous analysons les résultats de cette évaluation, ce qui confirme partiellement l’hypothèse de l’expérience et affirme que la présence de l’ACA dans l’EV ne dégrade pas la performance de l’apprenant dans le contexte de l’apprentissage d’une procédureVirtual Reality plays a major role in developing new educational methodologies, and allows to develop virtual environments for learning where intelligent virtual agents play the role of tutors. These agents are expected to help human users to learn and apply domain-specific procedures with predefined learning outcomes. We work on building a real-time system able to sustain natural interaction with the user in a Virtual Learning Environment (VLE). To implement this model, we propose to use the Multi-Agent System for Collaborative, Adaptive & Realistic Environments for Training (MASCARET) as an Intelligent Virtual Environment (IVE) model that provides the knowledge base to the agents and model the semantic of the virtual environment and user’s activities. To formalize the intention of the agents, we implement a cognitive module within MASCARET inspired by BDI (Belief-Desire-Intention) architecture that permits us to generate high-level intentions for the agents. Furthermore, we integrate Embodied Conversational Agents (ECA), which are based on the SAIBA (Situation, Agent, Intention, Behavior, Animation) framework. The embodied agents of the environment have communicative intentions that are transmitted to the user through natural communication channels, namely the verbal and non-verbal communicative acts and behaviors of the ECAs. To evaluate our model, we implement it in a concrete pedagogical scenario for learning blood analysis procedures in a biomedical laboratory. We use this application to settle an experiment to validate the propositions of our model. The hypothesis of this experiment is to assume that the presence of anECA in a Virtual Environment (VE) enhances the learning performance (or at least does not degrade it) in the context of a learning procedure. The performance is represented by the time of execution, the number of committed errors and the number of requests for assistance. We analyze the results of this evaluation, which partially confirms the hypothesis of the experiment and assure that having an ECA in the VLE does not degrade the performance of the learner in the context of a learning procedure
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Silva, Tadeu Augusto de Almeida. "Uso de ambientes virtuais para a simulação de acidentes radiológicos." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=4118.
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Em um ambiente virtual, construído com o uso de tecnologia computacional,
encontram-se presentes entidades virtuais inseridas em um espaço tridimensional, que é
utilizado para a simulação de processos críticos, como os acidentes radiológicos. A
pronta detecção de um acidente radiológico e a determinação da sua possível extensão
são fatores essenciais para o planejamento de respostas imediatas e de ações de
emergência. A integração das representações georeferenciadas do espaço
tridimensional, com modelos baseados em agentes autônomos, com o objetivo de
construir ambientes virtuais que tenham a capacidade de simular acidentes radiológicos
é a proposta dessa tese. As representações georeferenciadas do espaço tridimensional
candidatas são: i)as representações espaciais usadas nos sistemas de informações
geográficas (SIG) e ii) a representação adotada pelo Google MapsTM. Com o uso deste
ambiente pode-se: quantificar as doses recebidas pelas pessoas; ter uma distribuição
espacial das pessoas contaminadas; estimar o número de indivíduos contaminados;
estimar o impacto na rede de saúde; estimar impactos ambientais; gerar zonas de
exclusão; construir cenários alternativos; treinar pessoal técnico para lidar com
acidentes radiológicos.In a virtual environment, built with the use of computer technology, there are virtual entities, inserted into a virtual three-dimensional space, which is used to simulate critical processes, such as radiological accidents. Early detection of a radiological accident and determining its possible extension are essential for planning an immediate response and emergency actions. The purpose of this thesis is to build virtual environments that have the ability to simulate radiological accidents. These virtual environments are based on the integration of georeferenced representations of the three dimensional space with autonomous agents-based models. The georeferenced representations candidates are: i) the spatial representation used in geographic information systems (GIS); ii) the representation adopted by Google MapsTM. Using these virtual environments, in case of occurrences of radiological accidents, it will be possible to quantify the doses received by people, have a spatial distribution of infected persons; estimate the number of infected individuals; estimate the impact on the health network, estimate environmental impacts, generate exclusion zones, building scenarios alternative; train staff for dealing with these accidents.
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Jaafar, Jafreezal. "Reactive behaviour for autonomous virtual agents using fuzzy logic." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/8317.
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One of the fundamental aspects of a virtual environment is the virtual agents that inhabit them. In many applications, virtual agents are required to perceive input information from their environment and make decisions appropriate to their task based on their programmed reaction to those inputs. The research presented in this thesis focuses on the reactive behaviour of the agents. We propose a new control architecture to allow agents to behave autonomously in navigation tasks in unknown environments. Our behaviour-based architecture uses fuzzy logic to solve problems of agent control and action selection and which can coordinate conflicts among different operations of reactive behaviours. A Fuzzy Associative Memory (FAM) is used as the process of encoding and mapping the input fuzzy sets to the output fuzzy set and to optimise the fuzzy rules. Our action selection algorithm is based on the fuzzy α-level method with the Hurwicz criterion. The main objective of the thesis was to implement agent navigation from point to point by a coordination of planning, sensing and control. However, we believe that the reactive architecture emerging from this research is sufficiently general that it could be applied to many applications in widely differing domains where real-time decision making under uncertainty is required. To illustrate this generality, we show how the architecture is applied to a different domain. We chose the example of a computer game since it clearly demonstrates the attributes of our architecture: real-time action selection and handling uncertainty. Experimental results are presented for both implementations which show how the fuzzy method is applied, its generality and that it is robust enough to handle different uncertainties in different environments. In summary, the proposed reactive architecture is shown to solve aspects of behaviour control for autonomous virtual agents in virtual environments and can be applied to various application domains.
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Wen, Zhigang. "Real time animated human agent in virtual environments." Thesis, University of Wolverhampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413437.
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Cony, Carlos Akcelrud. "Simulação de agentes virtuais dotados de percepção sintética em situações de emergência." Universidade do Vale do Rio do Sinos, 2008. http://www.repositorio.jesuita.org.br/handle/UNISINOS/2259.
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Este trabalho apresenta um modelo para prover habilidades perceptivas (visão, olfato e audição) aos agentes virtuais, focando em aplicações de simulação de multidões em situações de emergência. Os modelos visual e olfativo foram baseados em trabalhos já publicados por autores da literatura, enquanto que a audição virtual foi modelada com maiores detalhes. A modelagem do sistema auditivo baseou-se em características reais, tais como as atenuações do som em relação às perdas energéticas causadas pelas paredes (refrações) e distância percorrida pelo som. Além destas, foram estudados alguns comportamentos fisiológicos do ouvido humano, tais como a dificuldade em que um ser humano tem em ouvir determinadas bandas de freqüência, perdas auditivas decorrentes do envelhecimento, e ainda possíveis doenças auditivas. Ainda, aplicou-se um modelo de mascaramento sonoro, no qual alguns sons podem ser mascarados por outros com freqüências similares. O modelo perceptivo virtual foi avaliado em aplicações de simulação de
This work presents a model to provide perceptual abilities (vision, smelling and hearing) to virtual agents, focusing on applications of crowd simulation for emergency situations. The models for synthetic vision and hearing were based on papers published by known authors, while the virtual hearing was modeled in details. The synthetic hearing model was based on real characteristics, such as sound attenuation caused by walls and distance from the sound source. Also, some physiological behaviors of the human hear were considered, such as the natural diffculty of a human being to hear some frequency bands, and hearing losses due to aging. Finally, the hearing model also included masking effects, in which some sounds may be masked by others with similar frequencies. The proposed perceptual model was evaluated in applications of crowd simulation for emergency situations, in which an alarm was placed into different positions of the virtual environment, and the agents had to decide what to do based on their percept
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Ho, Wan Ching. "Computational memory architectures for autobiographic and narrative virtual agents." Thesis, University of Hertfordshire, 2005. http://hdl.handle.net/2299/7772.
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This thesis develops computational memory architectures for autobiographic and narrative virtual agents. Humans and many animals naturally possess a sophisticated memory system for reasoning, learning and also sharing information with others. However it has been a difficult challenge to model the characteristics of such a memory system in the research fields of both Artificial Intelligence and Artificial Life. We propose a framework for enhancing reactive autonomous agents to retrieve meaningful information from their dynamic memories in order to adapt and survive in their environments. Our approach is inspired by psychology research in human memory and autobiographic memory – through remembering the significance of episodic events that happened in the past, agents with autobiographic memory architectures are capable of reconstructing past events for the purpose of event re-execution and story-telling. The memory architectures that were developed are capable of organizing and filtering significant events which originate in agents’ own experiences as well as stories told by other agents. To validate our memory architectures, both simple and complex Artificial Life type of virtual environments with static as well as dynamic resources distribution were implemented that provide events with different levels of complexity and affect the internal variables of the agents. The performance of various types of agents with different memory control architectures are first compared in single-agent experiments. Each agent’s behaviour is observed and analysed quantitatively together with its lifespan and internal states measurements. Group performance with and without communication are measured in experiments with multiple autobiographic ii agents. Results confirm our research hypothesis that autobiographic memory can prove beneficial – resulting in increases in the lifespan of an autonomous, autobiographic, minimal agent. Furthermore, higher communication frequency brings better group performance for Long-term Autobiographic Memory agents in multi-agent experiments. An interface has been developed to visualise agents’ dynamic autobiographic memory to help human observers to understand the underlying memory processes. This research leads to insights into how bottom-up story-telling and autobiography reconstruction in artificial autonomous agents allow temporally grounded behaviour to emerge. This study therefore results in a contribution to knowledge in Artificial Life and Artificial Intelligence.
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Shulman, David Mark. "Investigating Wikis as Agents for Virtual Team Activity Awareness." NSUWorks, 2010. http://nsuworks.nova.edu/gscis_etd/358.
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Virtual team collaboration through the Internet has become a commonplace event for preparing and publishing collaboratively authored documents. While collaborative technologies are now ubiquitous through the advent of Web 2.0, there is still considerable work required to ensure that virtual team members are able to maintain a sufficient level of activity awareness about other members and their roles and contributions in the collaborative authoring of a document. The goal was to measure and evaluate wiki notification mechanisms as agents to significantly raise activity awareness for virtual teams engaged in collaborative authoring.
Virtual teams collaboratively authored a project over a sixteen-week term using team wikis. The participants were undergraduate students divided into groups of between 25 and 27 each in three online business courses. Attention focused on the significance of e-mail and RSS notifications as agents for raising activity awareness. Evaluation of the effect of notification mechanisms on activity awareness was done with a pretest-posttest control group design and a descriptive analysis of data, plus a posttest only design to test for significant academic achievement gains on projects.
The Activity Awareness Questionnaire with IRC Domains and Levels was used to measure activity awareness. Additionally, a pedagogical evaluation of student success based on treatment type was undertaken. The ANOVA was used for measuring virtual team academic success between the control and treatment groups.
In general the data analysis suggested that the use of RSS and e-mail notification did not have a significant impact on either activity awareness or virtual team academic performance.
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Fortes, Neto Amyr Borges. "Giving emotional contagion ability to virtual agents in Crowds." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2017. http://tede2.pucrs.br/tede2/handle/tede/7769.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
Modelos de simula??o de multid?es t?m tido um papel importante em ci?ncias da computa??o j? h? algumas d?cadas desde os trabalhos pioneiros. No in?cio, agentes simulados em multid?es comportavam-se todos da mesma maneira, e tal comportamento era controlado pelas mesmas regras em todos os agentes. Com o tempo, os modelos de simula??o evoluiram, e come?aram a agregar uma maior variedade de comportamentos nos agentes. Modelos de simula??o de multid?es que implementam diferentes comportamentos nos agentes s?o chamados modelos de Multid?es Heterog?neas, em oposi??o aos modelos de Multid?es Homog?neas precedentes. Modelos de simula??o de multid?es que buscam criar agentes com comportamentos humanos realistas exploram heterogeneidade nos comportamentos dos agentes, na tentativa de atingir tal realismo. Em geral, estudos em psicologia e comportamento humano s?o usados como conhecimento de base, e os comportamentos observados nestes estudos s?o simulados em agentes virtuais. Nesta dire??o, trabalhos recentes em simula??o de multid?es exploram caracter?sticas de personalidade e modelos de emo??es. No campo de emo??es em agentes virtuais, pesquisadores est?o tentando recriar fen?menos de cont?gio de emo??es em pequenos grupos de agentes, ou mesmo estudar o impacto de cont?gio de emo??o entre agentes virtuais e participantes humanos. Sob a cren?a de que cont?gio de emo??o em agentes virtuais possa levar a comportamentos mais realistas em multi?es, este trabalho foca em recriar modelos computacionais de cont?gio de emo??es destinados a pequenos grupos de agentes, adaptando estes modelos para um contexto de simula??o de multid?es.
Crowd simulation models have been playing an important role in computer sciences for a few decades now, since pioneer works. At the beginning, agents simulated on crowds behaved all the same way, such behaviour being controlled by the same set of rules. In time, simulation models evolved and began to incorporate greater variety of behaviours. Crowd simulation models that implement different agent behaviours are so-called Heterogeneous Crowd models, opposing to former Homogeneous Crowd models. Advances in crowd simulation models that attempt to make agents with more realistic human-like behaviours explore heterogeneity of agent behaviours in order to achieve overall simulation realism. In general, human behavioural and psychological studies are used as base of knowledge to simulate observed human behaviours within virtual agents. Toward this direction, later crowd simulation works explore personality traits and emotion models. Some other work in the field of emotional virtual agents, researchers are attempting to recreate emotion contagion phenomena in small groups of agents, and even studying emotion contagion impact between virtual agents and human participants. Under the belief that emotion contagion in virtual agents might lead to more realistic behaviours on crowds, this work is focused on recreating emotion contagion computational models designed for small groups of agents, and adapting it for crowd simulation context.
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Gu, Ning. "Dynamic Designs of Virtual Worlds Using Generative Design Agents." Thesis, The University of Sydney, 2006. http://hdl.handle.net/2123/984.
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This research aims at developing a different kind of virtual world that is dynamically designed and implemented as needed. Currently, most virtual world designs are considered static. Similar to the physical world, these worlds are pre-defined prior to their use. The resultant environments serve certain purposes but do not take into consideration possible changes to the purposes during their use, changes which often occur when the occupants interact with the environments and with each other. Virtual worlds as networked environments can be flexibly configured and programmed. This flexibility makes it possible to consider virtual world designs in terms of dynamics and autonomy, reflecting the changing needs of different moments. To achieve dynamic designs of virtual worlds, this study applies a computational approach using rational design agents. A Generative Design Agent (GDA) model is developed that specifies computational processes for reasoning and designing in virtual worlds. The GDAs serve as personal design agents to the virtual world occupants. Design formalisms for virtual worlds are also addressed. The design component of a GDA is supported by the application of a generative design grammar. On one hand, generative design grammars serve as the generative force to be applied by the GDAs for virtual world design automation. On the other hand, each grammar defines coherent stylistic characterisations shared by the virtual world designs it generates. The technical outcomes of the research consist of the GDA model and a generative design grammar framework. The framework provides guidelines and strategies to designers for developing generative design grammars that produce different design languages for virtual worlds, rather than predefine every detail of all possible virtual world designs. GDAs monitor the virtual worlds and the various activities that occur in the worlds, interpret the occupants’ needs in the virtual worlds and the state of the worlds based on these observations, hypothesise design goals in order to satisfy these needs, and finally apply generative design grammars to provide virtual world designs for the moment, or initiate other actions in the worlds, according to the current design goals, on behalf of the occupants. The development of the GDA model and the generative design grammar framework provides new perspectives for understanding and developing virtual worlds. The GDA model challenges the conventional way that virtual worlds are designed and implemented, and this leads to dynamic designs of virtual worlds. The generative design grammar framework provides a computational approach to formally defining design languages for virtual worlds.
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Gu, Ning. "Dynamic Designs of Virtual Worlds Using Generative Design Agents." Architecture, 2006. http://hdl.handle.net/2123/984.
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Doctor of Philosophy (PhD)This research aims at developing a different kind of virtual world that is dynamically designed and implemented as needed. Currently, most virtual world designs are considered static. Similar to the physical world, these worlds are pre-defined prior to their use. The resultant environments serve certain purposes but do not take into consideration possible changes to the purposes during their use, changes which often occur when the occupants interact with the environments and with each other. Virtual worlds as networked environments can be flexibly configured and programmed. This flexibility makes it possible to consider virtual world designs in terms of dynamics and autonomy, reflecting the changing needs of different moments. To achieve dynamic designs of virtual worlds, this study applies a computational approach using rational design agents. A Generative Design Agent (GDA) model is developed that specifies computational processes for reasoning and designing in virtual worlds. The GDAs serve as personal design agents to the virtual world occupants. Design formalisms for virtual worlds are also addressed. The design component of a GDA is supported by the application of a generative design grammar. On one hand, generative design grammars serve as the generative force to be applied by the GDAs for virtual world design automation. On the other hand, each grammar defines coherent stylistic characterisations shared by the virtual world designs it generates. The technical outcomes of the research consist of the GDA model and a generative design grammar framework. The framework provides guidelines and strategies to designers for developing generative design grammars that produce different design languages for virtual worlds, rather than predefine every detail of all possible virtual world designs. GDAs monitor the virtual worlds and the various activities that occur in the worlds, interpret the occupants’ needs in the virtual worlds and the state of the worlds based on these observations, hypothesise design goals in order to satisfy these needs, and finally apply generative design grammars to provide virtual world designs for the moment, or initiate other actions in the worlds, according to the current design goals, on behalf of the occupants. The development of the GDA model and the generative design grammar framework provides new perspectives for understanding and developing virtual worlds. The GDA model challenges the conventional way that virtual worlds are designed and implemented, and this leads to dynamic designs of virtual worlds. The generative design grammar framework provides a computational approach to formally defining design languages for virtual worlds.
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Zhang, Yi. "Simulation of emotional behaviours for virtual agents with personalities." Thesis, Curtin University, 2015. http://hdl.handle.net/20.500.11937/2023.
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We have proposed an improved emotion model based on the well-known PAD model in affective computing and the NEO PI-R personality model in psychology. A novel parameter Emotion Intensity (EI) is proposed to represent different strength of anger, disgust, fear, happiness and sadness. Another novel Resistant formulation is also proposed to effectively simulate the complicated negative emotions. Eight experiments are conducted to simulate different emotional responses under different stimuli with different personality traits.
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Taoum, Joanna. "MEMORIA, un Modèle de rEprésentation de la MémOire de l'appRenant pour les systèmes tutoriels Intelligents et Adaptatifs." Thesis, Brest, 2018. http://www.theses.fr/2018BRES0117/document.
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Dans cette thèse, nous présentons MEMORIA, un modèle de représentation de la mémoire de l’apprenant pour les systèmes tutoriels intelligents et adaptatifs. La contribution principale de ce modèle est une formalisation et une implémentation du modèle de l’apprenant sous forme de mémoires qui stockent les informations perçues par l’apprenant dans un environnement virtuel et les instructions émises par le tuteur. La conception de notre modèle est basée sur les quatre composantes classiques d’un système tutoriel intelligent. Le modèle du domaine est représenté par les connaissances métiers formalisées à l'aide de MASCARET. Afin de rendre naturelles les interactions entre le tuteur et l'apprenant, nous représentons le modèle de l'interface par l'intermédiaire d'un agent conversationnel animé à l'aide de la plate-forme Greta. Le modèle de l'apprenant est constitué de l'ensemble des connaissances acquises par l'apprenant en cours de simulation. Ces connaissances sont organisées dans trois mémoires : la mémoire sensorielle, la mémoire de travail et la mémoire à long terme. Notre enjeu majeur porte sur la formalisation de l'encodage des informations dans ces mémoires, ainsi que le flux de données entre celles-ci. Cette formalisation est basée sur la théorie de la mémoire humaine proposée par Atkinson et Shiffrin et inspirée de l'architecture cognitive ACT-R. Le modèle de tuteur que nous proposons est centré sur la réalisation d'un comportement qui adapte l'exécution du scénario en fonction des connaissances de l'apprenant et de ses interactions avec le tuteur. Une étude expérimentale a été menée pour valider notre modèle. Nous avons comparé deux groupes de participants. Dans le premier groupe, nous avons intégré un tuteur adaptatif utilisant notre modèle, qui adapte l'exécution du scénario pédagogique et dans le second groupe, un tuteur non adaptatif qui réalise un scénario pédagogique figé. Les résultats de cette étude permettent de conclure quant à l'efficacité de notre modèle pour un apprentissage de procédureIn this thesis, we present MEMORIA, a model of the learner’s memory representation for adaptive and intelligent tutoring systems. The main contribution of this model is a formalization and an implementation of the learner's model using memories that store the information perceived by the learner in a virtual environment and the instructions given by the tutor. The design of our model is based on the four classic components of an intelligent tutorial system.The domain model is represented by the domain knowledge that is formalized using MASCARET. In order to make the interactions between the tutor and the learner natural, we represent the interface model through an embodied conversational agent using GRETA. The learner's model is made of all the knowledge acquired by the learner during the simulation. This knowledge is organized into three memories: sensory memory, working memory, and long-term memory. Our major challenge is to formalize the encoding of information in these memories, as well as the data flow between them.This formalization is based on the theory of human memory proposed by Atkinson and Shiffrin and inspired by the cognitive architecture ACT-R. Our proposed tutor model focuses on the realization of a behavior that adapts the execution of the pedagogical scenario according to the learner's knowledge and the interactions with the tutor. An experimental study was conducted to validate our model. We compared two groups of participants. In the first group, we integrated an adaptive tutor using our model which adapts the execution of the pedagogical scenario and in the second group, a non-adaptive tutor who applied a fixed pedagogical scenario. The results of this study allow us to conclude on the effectiveness of our model for procedural learning
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Le, Corre Frédéric. "CHRYSAOR : un Système Tutoriel Intelligent pour les Environnements Virtuels d'Apprentissage Humain. Application à la formation au matériel de laboratoire en hémostase : application à la formation au matériel de laboratoire en hémostase." Thesis, Brest, 2013. http://www.theses.fr/2013BRES0083/document.
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Ce travail de recherche s'inscrit dans le cadre des environnements virtuels pour la formation aux instruments de diagnostic biomédical. La simulation de la situation réelle seule ne suffisant pas, il convient d'incorporer un scénario pédagogique pour construire l'apprentissage. Le scénario s'applique pour tous les apprenants, il est donc important d'intégrer des possibilités d'individualisation. Pour cela, nous proposons de coupler l'environnement virtuel à un Système Tutoriel Intelligent (STI). Notre étude débute par une identification des systèmes existants qui nous semblent les mieux adaptés, sur lesquels baser notre proposition : le STI Pégase, le modèle de scénario pédagogique Poseïdon et le méta-modèle Mascaret. Ceci nous permet également d'identifier les limites de Pégase qui sont : le manque de lien avec le scénario pédagogique, le manque de modularité et le manque d'individualisation. Notre proposition, appelée Chrysaor, vise à combler ces faiblesses. Nous proposons ainsi qu'un scénario pédagogique soit une connaissance explicite et par conséquent exploitable par un STI. Les concepts proposés dans notre modèle permettent également au formateur de facilement modifier les comportements, les rôles et les affectations (humain ou agent autonome) : notre système devient ainsi modulaire. Nous illustrons ensuite l'utilisation de Chrysaor dans une application de formation par la réalité virtuelle à un instrument de diagnostic en hémostase utilisé en milieu hospitalier. Sur cette application, des expérimentations comparant les deux types de formation (traditionnelle et virtuelle) permettent de vérifier la qualité de l'apprentissage obtenu par une formation en réalité virtuelle, et de vérifier que ces connaissances sont transférables en environnement réelThis research focuses on the virtual environments for training in biomedical diagnostic devices. The simulation of the real situation only is not enough, we needs to incorporate a pedagogical scenario to build the learning. The scenario applies to all learners, so it is important to integrate individualization. For this we propose to couple the virtual environment with an Intelligent Tutoring System (ITS). Our study begins with an identification of existing systems that seem best suited, on which to base our proposal: the ITS Pegase, the pedagogical scenario model Poseidon and the meta-model Mascaret. This also allows us to identify the limits of Pegase : the lack of connection with the pedagogical scenario, the lack of modularity and lack of individualization. Our proposal, called Chrysaor, aims to provide the most complete ITS. Thus we propose that a pedagogical scenario is an explicit knowledge and therefore exploitable by an STI. The concepts proposed in our model also allow the instructor to easily modify the behavior, roles and assignments (human or autonomous agent): our system becomes modular. Then we illustrate the use of Chrysaor in an application of virtual reality training in a biomedical device used in hemostasis in hospital. We lead two experiments in order to compare the two types of training (traditional and virtual) to verify the quality of learning achieved by a virtual reality training, and to ensure that this knowledge are transferable in a real environment
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Barange, Mukesh. "Task-oriented communicative capabilities of agents in collaborative virtual environments for training." Thesis, Brest, 2015. http://www.theses.fr/2015BRES0013/document.
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Les besoins croissants en formation et en entrainement au travail d’équipe ont motivé l’utilisationd’Environnements de réalité Virtuelle Collaboratifs de Formation (EVCF) qui permettent aux utilisateurs de travailler avec des agents autonomes pour réaliser une activité collective. L’idée directrice est que la coordination efficace entre les membres d’une équipe améliore la productivité et réduit les erreurs individuelles et collectives. Cette thèse traite de la mise en place et du maintien de la coordination au sein d’une équipe de travail composée d’agents et d’humains interagissant dans un EVCF.L’objectif de ces recherches est de doter les agents virtuels de comportements conversationnels permettant la coopération entre agents et avec l’utilisateur dans le but de réaliser un but commun.Nous proposons une architecture d’agents Collaboratifs et Conversationnels, dérivée de l’architecture Belief-Desire-Intention (C2-BDI), qui gère uniformément les comportements délibératifs et conversationnels comme deux comportements dirigés vers les buts de l’activité collective. Nous proposons un modèle intégré de la coordination fondé sur l’approche des modèles mentaux partagés, afin d’établir la coordination au sein de l’équipe de travail composée d’humains et d’agents. Nous soutenons que les interactions en langage naturel entre les membres d’une équipe modifient les modèles mentaux individuels et partagés des participants. Enfin, nous décrivons comment les agents mettent en place et maintiennent la coordination au sein de l’équipe par le biais de conversations en langage naturel. Afin d’établir un couplage fort entre la prise de décision et le comportement conversationnel collaboratif d’un agent, nous proposons tout d’abord une approche fondée sur la modélisation sémantique des activités humaines et de l’environnement virtuel via le modèle mascaret puis, dans un second temps, une modélisation du contexte basée sur l’approche Information State. Ces représentations permettent de traiter de manière unifiée les connaissances sémantiques des agents sur l’activité collective et sur l’environnement virtuel ainsi que des informations qu’ils échangent lors de dialogues.Ces informations sont utilisées par les agents pour la génération et la compréhension du langage naturel multipartite. L’approche Information State nous permet de doter les agents C2BDI de capacités communicatives leur permettant de s’engager pro-activement dans des interactions en langue naturelle en vue de coordonner efficacement leur activité avec les autres membres de l’équipe. De plus, nous définissons les protocoles conversationnels collaboratifs favorisant la coordination entre les membres de l’équipe. Enfin, nous proposons dans cette thèse un mécanisme de prise de décision s’inspirant de l’approche BDI qui lie les comportements de délibération et de conversation des agents. Nous avons mis en oeuvre notre architecture dans trois différents scénarios se déroulant dans des EVCF. Nous montrons que les comportements conversationnels collaboratifs multipartites des agents C2BDI facilitent la coordination effective de l’utilisateur avec les autres membres de l’équipe lors de la réalisation d’une tâche partagéeGrowing needs of educational and training requirements motivate the use of collaborative virtual environments for training (CVET) that allows human users to work together with autonomous agents to perform a collective activity. The vision is inspired by the fact that the effective coordination improves productivity, and reduces the individual and team errors. This work addresses the issue of establishing and maintaining the coordination in a mixed human-agent teamwork in the context of CVET. The objective of this research is to provide human-like conversational behavior of the virtual agents in order to cooperate with a user and other agents to achieve shared goals.We propose a belief-desire-intention (BDI) like Collaborative Conversational agent architecture(C2BDI) that treats both deliberative and conversational behaviors uniformly as guided by the goal-directed shared activity. We put forward an integrated model of coordination which is founded on the shared mental model based approaches to establish coordination in a human-agent teamwork. We argue that natural language interaction between team members can affect and modify the individual and shared mental models of the participants. Finally, we describe the cultivation of coordination in a mixed human-agent teamwork through natural language conversation. In order to establish the strong coupling between decision making and the collaborative conversational behavior of the agent, we propose first, the Mascaret based semantic modeling of human activities and the VE, and second, the information state based context model. This representation allows the treatment of semantic knowledge of the collaborative activity and virtual environment, and information exchanged during the dialogue conversation in a unified manner. This knowledge can be used by the agent for multiparty natural language processing (understanding and generation) in the context of the CEVT. To endow the communicative capabilities to C2BDI agent, we put forward the information state based approach for the natural language processing of the utterances. We define collaborative conversation protocols that ensure the coordination between team members. Finally, in this thesis, we propose a decision making mechanism, which is inspired by the BDI based approach and provides the interleaving between deliberation and conversational behavior of the agent. We have applied the proposed architecture to three different scenarios in the CVET. We found that the multiparty collaborative conversational behavior of C2BDI agent is more constructive and facilitates the user to effectively coordinate with other team members to perform a shared task
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Chen, Jianrong. "An architecture for agent-oriented virtual inhabited call centres." Thesis, Oxford Brookes University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.250511.
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Back, David N. "Agent-based soldier behavior in dynamic 3D virtual environments." Thesis, Monterey, California. Naval Postgraduate School, 2002. http://hdl.handle.net/10945/6095.
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Human behavior in virtual environments is commonly implemented as a finite state machine. This programming approach can be effective and challenging against human players, but its ability to realistically simulate the behavior of cooperative groups of soldiers is limited. This thesis covers the development of an agent-based system to control the behavior of infantry in 3D virtual environments. The system design divides the cognitive process into four modules: perception, mental model, goal, decision, and action resolution. Each module attempts to simulate both strengths and weaknesses of human perception and cognition, including instinctive reactions, perceptual error, memory degradation, context-dependent decision-making, and inference. Additionally, the soldiers are influenced by the actions and decisions of the agents around them, enabling cooperation. The resultant agent system was incorporated into a game-like interface and compared to a similar commercial game with standard AI. Overall, 72% of the test subjects thought that the agent behaviors were Mostly Realistic or Totally Realistic, and 81% found them to be equal to or better than those in the commercial game.
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Henry, Joseph William Roger. "Interactive control of multi-agent motion in virtual environments." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/19580.
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With the increased use of crowd simulation in animation, specification of crowd motion can be very time consuming, requiring a lot of user input. To alleviate this cost, we wish to allow a user to interactively manipulate the many degrees of freedom in a crowd, whilst accounting for the limitation of low-dimensional signals from standard input devices. In this thesis we present two approaches for achieving this: 1) Combining shape deformation methods with a multitouch input device, allowing a user to control the motion of the crowd in dynamic environments, and 2) applying a data-driven approach to learn the mapping between a crowd’s motion and the corresponding user input to enable intuitive control of a crowd. In our first approach, we represent the crowd as a deformable mesh, allowing a user to manipulate it using a multitouch device. The user controls the shape and motion of the crowd by altering the mesh, and the mesh in turn deforms according to the environment. We handle congestion and perturbation by having agents dynamically reassign their goals in the formation using a mass transport solver. Our method allows control of a crowd in a single pass, improving on the time taken by previous, multistage, approaches. We validate our method with a user study, comparing our control algorithm against a common mouse-based controller. We develop a simplified version of motion data patches to model character-environment interactions that are largely ignored in previous crowd research. We design an environment-aware cost metric for the mass transport solver that considers how these interactions affect a character’s ability to track the user’s commands. Experimental results show that our system can produce realistic crowd scenes with minimal, high-level, input signals from the user. In our second approach, we propose that crowd simulation control algorithms inherently impose restrictions on how user input affects the motion of the crowd. To bypass this, we investigate a data-driven approach for creating a direct mapping between low-dimensional user input and the resulting high-dimensional crowd motion. Results show that the crowd motion can be inferred directly from variations in a user’s input signals, providing a user with greater freedom to define the animation.
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Ljunglöv, Robin. "Prestation, intresse, engagemang, uppskattning : Skillnader i upplevelse av en virtuell lärmiljö mellan matematiskt hög- och lågpresterande elever." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-69260.
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Digitala läromedel blir ett vanligare inslag i skolgången då ny teknologi erbjuder tidigare okända pedagogiska möjligheter. Denna uppsats undersöker hur elever som använder ett digitalt läromedel i form av en virtuell lärmiljö för matematiklärande upplever denna lärmiljö. Dessutom undersöks elevernas prestation i lärmiljöns matematiska uppgifter. Skillnader mellan elever i olika årskurser samt elever som är matematiskt låg- eller högpresterande studeras. Matematisk prestation beskrivs utifrån Goods (1981) passivitetsmodell som innebär att lågpresterande elever är mindre risktagande i klassrumsmiljön. Elevernas upplevelse av digitala läromedel studerades i en virtuell lärmiljö bestående av två moduler, en spelmodul och en modul för skriven dialog. Upplevelsen av lärmiljön undersöktes genom att studera hur intressant eleverna tyckte att spelet var, huruvida eleverna tyckte att agenten gjorde att de brydde sig mer när de spelade, samt om de gillade den skrivna dialogen. Tidigare insamlad data från elever i årskurs 6-8 som använt den virtuella lärmiljön undersöktes med kvasiexperimentell metod och analyserades med ANOVA. Analysen påvisade en skillnad mellan låg- och högpresterande elever i hur mycket de tycker att en pedagogisk virtuell agent engagerar dem i en virtuell lärmiljö. Matematiskt högpresterande elever anser att agenten gör dem mer engagerade än vad matematiskt lågpresterande elever anser. Detta kan tyda på att lågpresterande elevers passivitet utöver traditionell klassrumspedagogik också påverkar elevernas upplevelse av digitala läromedel. I vidareutvecklingen av den virtuella lärmiljön och skapandet av andra virtuella lärmiljöer är det viktigt att se till att elever både lär sig och engageras av lärmiljön. Utvecklare bör också ta hänsyn till de skillnader som finns mellan låg- och högpresterande elevers upplevelse av lärmiljön. Detta kan exempelvis ske genom att den virtuella lärmiljön görs anpassningsbar för att passa elever oberoende av prestationsnivå. Detta är en viktig målsättning för att se förbättra lågpresterande elevers möjligheter i skolan, något som virtuella lärmiljöer och digitala läromedel i allmänhet kan utgöra ett kraftfullt medium för.
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Conde, Toni. "Méthodes infographiques pour l'apprentissage des agents autonomes virtuels /." [S.l.] : [s.n.], 2005. http://library.epfl.ch/theses/?nr=3387.
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Pierce, Tyler. "Virtual Interactions with Real-Agents for Sustainable Natural Resource Management." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6002.
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Common pool resource management systems are complex to manage due to the absence of a clear understanding of the effects of users' behavioral characteristics. Non-cooperative decision making based on individual rationality (as opposed to group rationality) and a tendency to free ride due to lack of trust and information about other users' behavior creates externalities and can lead to tragedy of the commons without intervention by a regulator. Nevertheless, even regulatory institutions often fail to sustain natural common pool resources in the absence of clear understanding of the responses of multiple heterogeneous decision makers to different regulation schemes. While modeling can help with our understanding of complex coupled human-natural systems, past research has not been able to realistically simulate these systems for two major limitations: 1) lack of computational capacity and proper mathematical models for solving distributed systems with self-optimizing agents; and 2) lack of enough information about users' characteristics in common pool resource systems due to absence of reliable monitoring information. Recently, different studies have tried to address the first limitation by developing agent-based models, which can be appropriately handled with today's computational capacity. While these models are more realistic than the social planner's models which have been traditionally used in the field, they normally rely on different heuristics for characterizing users' behavior and incorporating heterogeneity. This work is a step-forward in addressing the second limitation, suggesting an efficient method for collecting information on diverse behavioral characteristics of real agents for incorporation in distributed agent-based models. Gaming in interactive virtual environments is suggested as a reliable method for understanding different variables that promote sustainable resource use through observation of decision making and behavior of the resource system beneficiaries under various institutional frameworks and policies. A review of educational or "serious" games for environmental management was undertaken to determine an appropriate game for collecting information on real-agents and also to investigate the state of environmental management games and their potential as an educational tool. A web-based groundwater sharing simulation game—Irrigania—was selected to analyze the behavior of real agents under different common pool resource management institutions. Participants included graduate and undergraduate students from the University of Central Florida and Lund University. Information was collected on participants' resource use, behavior and mindset under different institutional settings through observation and discussion with participants. Preliminary use of water resources gaming suggests communication, cooperation, information disclosure, trust, credibility and social learning between beneficiaries as factors promoting a shift towards sustainable resource use. Additionally, Irrigania was determined to be an effective tool for complementing traditional lecture-based teaching of complex concepts related to sustainable natural resource management. The different behavioral groups identified in the study can be used for improved simulation of multi-agent groundwater management systems.M.S.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Civil Engineering; Water Resources Engineering
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Nasman, James M. "Deployed virtual consulting : the fusion of wearable computing, collaborative technology, augmented reality and intelligent agents to support fleet aviation maintenance /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Mar%5FNasman.pdf.
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Thesis (M.S. in Information Technology Management)--Naval Postgraduate School, March 2004.Thesis advisor(s): Alex Bordetsky, Gurminder Singh. Includes bibliographical references (p. 49). Also available online.
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Tanner, Mark B. "Creating digital environments for multi-agent simulation." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03Dec%5FTanner.pdf.
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Thesis (M.S. in Modeling, Virtual Environments, and Simulation)--Naval Postgraduate School, December 2003.Thesis advisor(s): Wolfgang Baer, David W. Laflam. Includes bibliographical references (p. 61-63). Also available online.
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Wang, Anna, and Ingemar Weiner. "Kommer den fysiska resebyrån att överleva? : En undersökning om konkurrensen mellan den fysiska och virtuella resebyrån." Thesis, Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-30781.
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Syfte: Syftet med denna uppsats är att undersöka hur det kommer sig att den fysiska resebyrån finns kvar och hur framtiden ser ut hos dessa i och med teknologins snabba framväxt. Metod: Denna studie utgår ifrån en kvalitativ metod. För att samla in data till empirin har tio semistrukturerade intervjuer genomförts med olika resebyråer belägna i Stockholm, via personliga möten, telefon och e-post. De resebyråer som undersökts är Jade Travel, Lotus Travel, Resevaruhuset, Resecity, Apollo, Ving, Nygren & Lind, Jorden Resor, BIG Travel och Globetrotter. Teoretisk referensram: De teorier som använts i studien behandlar konsumentbeteende, distributionskanaler, servicescape, dynamiken av servicemötet och relationen mellan konsument och resebyrå. Slutsats: Den fysiska resebyrån har i och med teknologins framväxt förändrats på så sätt att dagens fysiska resebyråer värderar det fysiska servicemötet med kunden. En del fysiska resebyråer har minskat i antal men servicekvaliteten tillsammans med kompetens och kunskap hos de anställda i resebyråerna har blivit högre, detta föra att kunna konkurrera mot andra resebyråer och deras virtuella tjänster samt för att skapa en relation med konsumenterna.Purpose: The purpose of this essay is to examine why physical travel agencies still exist, and what the future looks like for those agencies since the technology's rapid growth. Method: This study is based on a qualitative methodology. Ten semi-structured interviews have been conducted for the empirical data. The interviews were held with various travel agencies located in Stockholm through personal meetings, telephone and e-mail. The travel agencies who participated in the interviews was; Jade Travel, Lotus Travel, Resevaruhuset, Resecity, Apollo, Ving, Nygren & Lind, Jorden Resor, BIG Travel and Globetrotter. Theoretical framework: The theories that have been used in this essay are consumer decision making, distribution channels, servicescape, the dynamics of the service encounter and the relationship between customer and travel agency. Conclusion: The physical travel agency has since the technology's development changed on a way that today's physical travel agencies evaluate the physical service meeting with the customer. Some physical agencies have decreased in number but the quality of service along with the skills and knowledge among employees of the travel agencies has increased, therefore to compete against other travel agencies and their virtual services, and to create a relationship with the consumers.
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Bahrammirzaee, Arash. "Contribution to study and design of intelligent virtual agents : application to negotiation strategies and sequences simulation." Phd thesis, Université Paris-Est, 2010. http://tel.archives-ouvertes.fr/tel-00587434.
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In this thesis, besides the developing a bilateral automated negotiation model between agents, in incomplete information state, integrating the personality effects of human on the negotiation process and outcomes, we proposed an architecture of such agents ("buyer" or "seller"). To do so, a new offer generation approach of three adaptive families of tactics has been proposed as follows : the time dependent tactics (time supposed as continuous), behavior dependent tactics, and time independent tactics.This thesis takes into consideration also the personality effects (of negotiator agent) on negotiation process and outcome. In fact, with regard to "Big five" personality model and introducing the cognitive orientations, we have developed a negotiator agent's architecture based on personality. This architecture is, mainly, inspired from the game theory. In fact, the artificial agent's cognition in terms of negotiation is considered as a certain negotiator's mental orientation favorising the concession of the negotiator agent towards one of following three equilibria (based on game theory) : Win-Lose, Lose-Win, and Win-Win According to the privileged orientation and the personality of negotiator, such a negotiator agent decides the adequate combination of tactics (models, etc) in order to modulate, consequently, the expected outcomes of negotiation
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Aguiar, Naomi. "The Biological, Psychological, and Social Properties Children and Adults Attribute to Virtual Agents." Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20690.
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For children, high quality friendships are associated with adaptive social, emotional and academic functioning. There is also evidence that children experience real and imaginary friendships in similar ways, and that imagined relationships could have an impact on development. However, less is known about the relationships made possible by virtual agents in digital media. This dissertation research was designed to provide preliminary data about children’s concepts of virtual agents, and the social opportunities they attribute to such entities.
In Studies 1 and 2 (combined N = 48), preschool aged children differentiated the social affordances of a stuffed dog and a virtual dog. Participants played a game in which they guessed whether a child in a video was referring to a stuffed dog or a virtual dog in a series of statements. Items designed to assess high quality friendships, such as comfort, protection and love, were attributed more to the stuffed dog than the virtual dog.
Studies 3 and 4 examined adult and child concepts of a virtual child, and how concepts of this entity might differ from a real child, a child on a video chat program (e.g., Skype™) and an inanimate doll. Adults and children attributed a range of properties to each child agent, including biological, psychological and social properties, as well as opportunities for relationships. In Study 3 (N = 144), adults did not differentiate between the virtual child and the doll on the social property; however, they favored the doll on opportunities for unilateral relationships. In Study 4 (N = 30), five to eight-year-old children indicated an overall preference for the doll on the social property, as well as on opportunities for reciprocal relationships. Children also favored the doll on opportunities for love, companionship, and intimate disclosure.
Altogether, these findings suggest that virtual agents afford more limited social opportunities than inanimate artifacts, and they are less likely to be loved by children and adults alike. These results raise important questions about the design goals for virtual agents, and the functions they are intended to serve in our everyday lives.
This dissertation includes both previously published and co-authored material.
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Almajano, Pablo. "Assisted Hybrid Structured 3D Virtual Environments." Doctoral thesis, Universitat de Barcelona, 2014. http://hdl.handle.net/10803/285805.
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The blending of digital technologies, such as artificial intelligence, interactive systems, 3D interfaces and the Internet is enabling new services for users. In particular, Hybrid Structured 3D Virtual Environments (VE) provide users with a collaborative space not only for entertainment and socialization but also for developing “serious” applications such as e-learning, e-government and e-commerce.
This thesis focuses on Hybrid Structured 3D VE, which are persistent multiuser systems where participants (both human users and software agents) develop “serious” activities. In these systems the 3D interface graphically represents the system and facilitates human participation, and an Organisation Centred Multi-Agent System (OCMAS) structures participants’ interactions. To do so, the OCMAS specifies the roles that participants can enact, the activities where complex tasks can be accomplished, and communication protocols that enable the prosecution of such tasks.
Nevertheless, participating in these systems is not a straight-forward process. Specifically, when the system speci.cation is complex, participants have to perform intricate reasoning processes to understand their applicable regulations at current system state; and they do not have access to information about what happened before they entered the system, neither can further process this information. Moreover, software agents speak a computer-based language, which is usually hard to use by human users. Then, as human users interact with staff agents (software agents devoted to support the system activities) to complete tasks, human-agent interaction style becomes a key issue.
In order to overcome these limitations, this work proposes Assisted Hybrid Structured 3D Virtual Environments, where both human users and software agents participation in the system is improved by both assistance and humanagent interaction mechanisms. The system is formalised as a two layered infrastructure. The Organisational Layer structures the interactions of participants, and the Assistance Layer is populated by a set of Personal Assistants in charge of providing with a set of Assistance services to a system participant. There are four types of Assistance services: i) an Information service that processes data about the organisation specification, the participant current state, and the organisational historical execution states; ii) a Justi.cation service that can be triggered once a participant tries to execute a non-valid or prohibited action; iii) an Estimation service that processes whether an action can be performed at current state prior to its execution or not and, if it is actually the case, then it also provides the next system state; and iv) an Advice service, which provides participants with a sequence of actions (i.e. plans) to achieve their goals.
Moreover, this work implements and evaluates v-mWater, a virtual market based on trading water, modelled as an Assisted Hybrid Structured 3D Virtual Environment. The usability evaluation results of v-mWater show that it is perceived as a useful and powerful application that could facilitate everyday tasks in the future. Users like its learnability, its immersiveness, and how scenario settings facilitate task accomplishment. In general, users completed the proposed task well and they were able to go to the right destination in the scenario. After doing the test, users improved their opinion about 3D virtual environments. In addition, the overall opinion of the human-agent interaction was positive. Nevertheless, those users less familiar with new technologies experimented problems when using a command-based system to interact with staff agents.
To support assistance services in the system, this work designs and evaluates an Assistance Architecture where the Information service is implemented for software agents; and the Justi.cation, Estimation and the planning Advice service for human users. Nonetheless, these four services could be offered interchangeably for both humans and software agents, since they all simplify the reasoning process as well as the cognitive load required to participate in these complex structured systems.
Speci.cally, the Information service has been extended to help sellers to set the price in their transactions. The tests performed compare the values that different agent satisfaction parameters and system goals take when agents request for different information services, using as a base-line a con.guration without enabling assistance services. The experiments show that system performance and agent satisfaction (and thus, the quality of assistance service) increase with the addition of the information service. Furthermore, individual agents following alternative strategies can request di.erent information as a useful decision support tool. The planning Advice service is the most sophisticated one and makes use of the rest of services to provide a plan that has into account other participants actions and, executed at current system state, will lead to the user’s goal. It is implemented as an extension of A*, namely Plan-eA. Evaluation results indicate that assistance impacts positively in usability measures of efficiency, efficacy and satisfaction.
Related to human-agent interaction, this work integrates a new conversational mechanism within VIXEE, an execution infrastructure for Hybrid Structured 3D Virtual Environments. This new mechanism includes a task-oriented conversational system, which allows staff agents to dialogue with human users using natural language conversations. To do so, this work proposes an extension of the well-known AIML language, namely Task-Oriented AIML, for dealing with task-oriented conversations, which are based on activities’ specification and current system state. Test results give good usability measures of efficiency, efficacy and user satisfaction for the conversational approach.
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Shen, Xiajun. "MAP: A mobile-agent-based platform for collaborative virtual environments." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/28964.
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With the enhanced performance of modern personal computer systems, the acceptance and distribution of 3D and virtual environment (VE) applications have become more common. The first VE systems were single user systems, but now we can see that distributed VE (DVE) and CSCW (Computer Supported Collaborative Work) can open new areas of applications. Currently one of the most challenging areas of research in Virtual Reality is Collaborative Virtual Environment (CVE). It adds new dimensions to human-factors, networking, synchronization, middleware, object model acquisition and representation.
Some international standards have been developed that are very likely to make a major impact on CVE technology: the Distributed Interactive Simulation (DIS) and the High Level Architecture (HLA). Deriving from military-purpose simulations, DIS and HLA, however, have limitations on building large-scale general-purpose CVE applications. For instance, HLA ownership management only allows single participant to manipulate objects at any given time while providing meaningful real-time manipulation of a single object among multiple geographically distant users is essential for users performing collaborative tasks.
The mobile agent technology that has received a rapidly growing attention over the last few years overcomes these limitations and could be an effective solution to building large-scale general-purpose CVE applications. This research addresses the software architecture and techniques necessary to apply the philosophy of mobile agents to collaborative virtual environments. For this purpose, a mobile agent system called MAP is designed and implemented. MAP supports general-purpose CVEs, enables object dynamic introduction, joint-manipulation management and maximizes system flexibilities such as dynamic composition and task coordination that are applied for building a workload balanced interest management system.
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Sause, William. "A Coordinated Reinforcement Learning Framework for Multi-Agent Virtual Environments." NSUWorks, 2013. http://nsuworks.nova.edu/gscis_etd/297.
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The growing popularity of online virtual communities such as Second Life and ActiveWorlds demands the presence of intelligent agents to assist users in their daily online activities (e.g., exploring, shopping, and socializing). As these virtual environments become more crowded, multiple agents are needed to support the increasing number of users. Multi-agent environments, however, can suffer from the problem of resource competition among agents. It is therefore necessary that agents within multi-agent environments include a coordination mechanism to prevent unrealistic behaviors. Moreover, it is essential that these agents exhibit some form of intelligence, or the ability to learn, to support realism as well as to eliminate the need for developers to write separate scripts for each task the agents are required to perform. This research presents a coordinated reinforcement learning framework which can be used to develop task-oriented intelligent agents in multi-agent virtual environments. The framework contains a combination of a "next available agent" coordination model and a reinforcement learning model consisting of existing temporal difference reinforcement learning algorithms. Furthermore, the framework supports evaluations of reinforcement learning algorithms to determine which methods are best suited for task-oriented intelligent agents in dynamic, multi-agent virtual environments.
To assess the effectiveness of the temporal difference reinforcement algorithms used in this study (Q-learning and Sarsa), experiments were conducted that measured an agent's ability to learn three tasks commonly performed by workers in a café environment. These tasks were basic sandwich making (BSM), complex sandwich making (CSM), and dynamic sandwich making (DSM). The BSM task consisted of four steps. The CSM and DSM tasks contained an additional fifth step. The agent learned the BSM and CSM tasks from scratch while the DSM task was learned after the agent became skillful in BSM. The measurements used to evaluate the efficiency of the Q-learning and Sarsa algorithms were the percentage of successful and optimally successful episodes performed by the agent and the average number of time steps taken by the agent to complete a successful episode. The experiments were run using both a fixed (FEP) and variable (VEP) ε-greedy probability rate. Results showed that the Sarsa reinforcement learning algorithm, on average, outperformed the Q-learning algorithm in almost all experiments except when measuring the percentage of successfully completed episodes using FEP for CSM and DSM, in which Sarsa performed almost equally as well as Q-learning. Overall, experiments utilizing VEP resulted in higher percentages of successes and optimal successes, and showed convergence to the optimal policy when measuring the average number of time steps per successful episode.
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Patel, Jigar. "A trust and reputation model for agent-based virtual organisations." Thesis, University of Southampton, 2006. https://eprints.soton.ac.uk/263318/.
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The aim of this research is to develop a model of trust that will endeavour to assure good interactions amongst autonomous software agents in complex, networked environments. In this context, we identify the following as key characteristics. Firstly, such environments are open, meaning that agents are free to enter and exit the system at their will, so an agent cannot be aware of all of its interaction partners. Furthermore, there is a possibility that these interaction partners may be malicious or colluding agents. Secondly, the openness and dynamism of these environments means agents will need to interact with other agents, with which they have had no past experience. Even in this context, an agent must be able to accurately assess the trustworthiness of another. Thirdly, the distributed and heterogeneous nature of these systems influences any model or application developed for such environments. Specifically, this often requires models and applications to be decentralised. Lastly, many of the interactions that occur between agents in such systems are in the context of a virtual organisation (VO). Here VOs are viewed as collections of agents belonging to different organisations, in which each agent has a specific problem solving capability which when combined provides a particular service to meet the requirements of an end user. Now, VOs are social structures, and the presence of certain inter-agent relationships may influence the behaviour of certain members. For this reason it is important to consider not only personal experiences with an individual to determine its behaviour, but to also examine the social relationships that it has with other agents. Against this background, we have developed TRAVOS (A Trust and Reputation Model for Agent-Based Virtual Organisations) which focuses, in particular, on providing a measure of trust for an agent to place in an interaction partner. This measure of trust is calculated by considering the past experiences between the agent and its interaction partner. In instances when there is no personal experience, the model substitutes past experience with reputation information gathered from other agents in the society or from special reputation broker agents. Reputation is gathered in a way that filters out biased or false opinions. In addition to this, the model is constrained by issues of scalability and decentralisation. Furthermore, by extending TRAVOS we developed a set of mechanisms (TRAVOS-R) related to learning and exploiting the social relationships present in VO-rich environments. More specifically, TRAVOS-R presents a novel approach to learning the type of relationship present between two agents, and uses this knowledge to adjust the opinions obtained from one agent about the other. The TRAVOS models have been tested empirically and have significantly outperformed other similar models. Moreover, to further evaluate the applicability of our approach a realistic system evaluation was also carried out, which involved applying our models in an industrial application of agent-based VOs. In undertaking this research, we have shown that trust is a key component of networked systems and that a computational trust model can be used by agents in large, dynamic, uncertain and open environments to account for the uncertainty inherent in their social decision-making processes. More specifically, we have shown that by using personal experience, opinions from others, and knowledge of social relationships, an agent is able to arrive at a more accurate trust value, and, as a consequence, that it can interact in a more effective manner.
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Rajagopal, Manoj Kumar. "Cloning with gesture expressivity." Phd thesis, Institut National des Télécommunications, 2012. http://tel.archives-ouvertes.fr/tel-00719301.
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Virtual environments allow human beings to be represented by virtual humans or avatars. Users can share a sense of virtual presence is the avatar looks like the real human it represents. This classically involves turning the avatar into a clone with the real human's appearance and voice. However, the possibility of cloning the gesture expressivity of a real person has received little attention so far. Gesture expressivity combines the style and mood of a person. Expressivity parameters have been defined in earlier works for animating embodied conversational agents.In this work, we focus on expressivity in wrist motion. First, we propose algorithms to estimate three expressivity parameters from captured wrist 3D trajectories: repetition, spatial extent and temporal extent. Then, we conducted perceptual study through a user survey the relevance of expressivity for recognizing individual human. We have animated a virtual agent using the expressivity estimated from individual humans, and users have been asked whether they can recognize the individual human behind each animation. We found that, in case gestures are repeated in the animation, this is perceived by users as a discriminative feature to recognize humans, while the absence of repetition would be matched with any human, regardless whether they repeat gesture or not. More importantly, we found that 75 % or more of users could recognize the real human (out of two proposed) from an animated virtual avatar based only on the spatial and temporal extents. Consequently, gesture expressivity is a relevant clue for cloning. It can be used as another element in the development of a virtual clone that represents a person