L'intelligence en essaim constitue désormais un domaine à part entière de l'intelligence artificielle distribuée. Les problématiques qu'elle soulève touchent cependant à de nombreux autres domaines ou questions scientifiques. En particulier le concept d'essaim trouve pleinement sa place au sein de la science dites des ``systèmes complexes''. Cette thèse présente ainsi la conception, les caractéristiques et les applications d'un modèle original, le système multi-agent logistique (SMAL), pour le domaine de l'intelligence en essaim. Le SMAL trouve son origine en modélisation des systèmes complexes : il est en effet issu des réseaux d'itérations logistiques couplées dont nous avons adapté le modèle de calcul au schéma ``influence-réaction'' des systèmes multi-agents. Ce modèle est fondé sur des principes communs à d'autres disciplines, comme la synchronisation et le contrôle paramétrique, que nous plaçons au coeur des mécanismes d'auto-organisation et d'adaptation du système. L'environnement à base de champs est l'autre aspect fondamental du SMAL, en permettant la réalisation des interactions indirectes des agents et en jouant le rôle d'une structure de données pour le système. Les travaux décrits dans cette thèse donnent lieu à des applications principalement en simulation et en optimisation combinatoire.L'intérêt et l'originalité du SMAL pour l'intelligence en essaim résident dans l'aspect générique de son schéma théorique qui permet de traiter avec un même modèle des phénomènes considérés a priori comme distincts dans la littérature : phénomènes de ``flocking'' et phénomènes stigmergiques ``fourmis'' à base de phéromones. Ce modèle répond ainsi à un besoin d'explication des mécanismes mis en jeu autant qu'au besoin d'en synthétiser les algorithmes générateurs. / Swarm Intelligence is from now on a full part of Distributed Artificial Intelligence. Its associated problematics meet many other fields and scientific questions. The concept of swarm in particular belongs to the science called the science of complex systems. This phd thesis shows the design and the characteristics and the applications of a novel type of model called the logistic multi-agent system (LMAS) dedicated to the Swarm Intelligence field. The LMAS has its foundations in complex system modeling: it is inspired from the coupled logistic map lattice model which has been adapted to the ``Influence-Reaction'' modeling of multi-agent systems. This model is based on universal principles such as synchronization and parametric control which are considered as the main mechanisms of self-organization and adaptation in the heart of the system. The field-layered based environment is the other important feature of the LMAS, since it enables indirect interactions and plays the part of a data structure for the whole system. The work of this thesis is put into practice for simulation and optimization.The novelty of the LMAS lies in its generic theoretical framework, which enables to tackle problems considered as distinct in the literature, in particular flocking and ant-like stigmergic behavior. This model meets the need of explaining basic mechanisms and the need of synthesizing generative algorithms for the Swarm Intelligence.

Les travaux présentés dans ce manuscrit portent sur la conduite de systèmes complexes critiques. Ils s'inscrivent dans le cadre du projet CONNEXION (Investissements d'Avenir, BGLE2) qui réunit les principaux acteurs de la filière nucléaire française autour de la conception des systèmes de contrôle-commande des centrales et de leur exploitation. Dans le domaine de la conduite, les actions développées par le projet concernent la phase d'ingénierie avec pour objectif d'intégrer le point de vue de l'exploitant au plus tôt dans la validation des architectures de contrôle de commande, et la phase d'exploitation avec pour objectif de fournir une aide à la préparation et à l'exécution des procédures de conduite. Dans ce contexte, la contribution présentée dans ce mémoire porte sur la génération et la vérification de séquences d'actions de conduite répondant à un objectif donné et pouvant être opérées en toute sécurité sur le procédé. L'approche proposée repose la vérification d'une propriété d'atteignabilité sur un réseau d'automates temporisés modélisant le comportement des architectures. L'originalité réside dans la définition d’un cadre formel de modélisation sous la forme de patrons favorisant la réutilisabilité des modèles ainsi que dans la proposition d'algorithmes d'abstraction et de recherche d'atteignabilité itératifs exploitant la hiérarchisation intrinsèque des architectures afin de permettre le passage à l'échelle de l'approche proposée. La contribution a été éprouvée sur la plate-forme d'expérimentation CISPI du CRAN puis sur un cas d'étude à échelle industrielle proposé dans le cadre du projet CONNEXION / The works presented in this manuscript deals with critical complex systems operation. They are part of the CONNEXION project (Investissements d'Avenir, BGLE2), which involves the main actors in the French nuclear industry around the design of control systems for power plants and their operation. In the operation field, the actions developed by the project concern the engineering phase with the aim of integrating the operator's point of view as soon as possible in the validation of control architectures, and the operation phase with the aim of providing assistance in the preparation and execution of operation procedures. In this context, the contribution presented in this manuscript deals with the generation and verification of action sequences that meet a given objective and that can be safely operated on the process. The proposed approach relies on verifying a reachability property on a network of timed automata modelling the behavior of architectures. The originality is in the definition of a formal modelling framework using patterns promoting the reusability of models, as well as in the proposition of abstraction and reachability iterative analysis algorithms exploiting the intrinsic hierarchization of architectures in order to scale-up of the proposed approach. The contribution was evaluated on the CISPI experimental platform of the CRAN, and on an industrial scale case study proposed within the framework of the CONNEXION project

Esta pesquisa trata do desenvolvimento de uma estrutura conceitual para um framework de maturidade, para o domínio de ecossistemas digitais de produção de software, utilizando a pesquisa-ação como paradigma de pesquisa. A estrutura de medição proposta tem como base o critério descrito no item 5 da Norma ISO/IEC 15504-2 Uma Estrutura de Medição para a capacidade de processo, com as adaptações necessárias para o domínio do Software Publico Brasileiro (SPB). O framework tem como objetivo o desenvolvimento de referências conceituais para um modelo de maturidade de um ecossistema público de software, considerando as referências do pensamento sistêmico. A abordagem do pensamento sistêmico permitiu identificar que o ecossistema evolui em ciclos de aprendizado que resultaram em um modelo de maturidade. Foi observado também que a mesma abordagem pode ser utilizada em outros ecossistemas. O objeto de pesquisa, o ecossistema do SPB, é uma experiência inovadora na administração pública, que combina características do modelo de produção de software livre com o conceito de bens públicos e é entregue por um portal que une pessoas e interesses diferentes. O portal do SPB é um espaço virtual para disseminação e aprimoramento de ferramentas de software. Em algumas comunidades acontecem atividades de desenvolvimento de novas funcionalidades ou mesmo de novas versões de ferramentas. Portanto, acontecem processos de desenvolvimento de software, porém ainda sem um processo de qualidade instituído. O desenvolvimento da pesquisa utilizou como referências teóricas frameworks de modelos de maturidade de processos, framework de métodos para construção de modelos, conceitos de sistemas complexos, pensamento sistêmico e ecossistemas digitais. A metodologia de pesquisa utilizada foi a pesquisa-ação e o trabalho de campo teve a duração de dois anos. / This research project addresses the development of a conceptual structure to measure the quality of software production in the digital ecosystem domain, using the action research paradigm. The proposed measurement framework is based on the criteria described in item 5 of ISO / IEC 15504-2 - A Measurement Framework for process capability, with the necessary adaptations to the Public Domain Software (PDS). Development of the structure aims to contribute to the creation of conceptual references for a maturity model for a public software development ecosystem, using the literature on Systems Thinking. The Systems Thinking Approach identified the ecosystem evolves in learning cycles that resulted in a maturity model. It was also observed that the same approach can be used in other ecosystems. The research object is the Brazilian Public Software Ecosystem (BPS), an innovative experience in public administration that combines features of the free software production model with the concept of public goods and is delivered by a portal that links different people and interests. The BPS portal is a virtual space for the development, dissemination and enhancement of software by software communities. These communities engage in activities involving the development of new functionality or even new versions of solutions. Thus they involve software development processes but without a minimum of quality assurance. The theoretical references for the research project ranged from frameworks for process maturity models and frameworks for model construction to concepts of complex systems, systemic thinking and digital ecosystems. The research methodology used was action research and the field work had duration of two years.

Submitted by Maicon Juliano Schmidt (maicons) on 2015-04-18T13:34:29Z No. of bitstreams: 1 Isis da Costa Pinho.pdf: 4020024 bytes, checksum: e23e8e48a9a7db1bd90be0d18227c6d8 (MD5) / Made available in DSpace on 2015-04-18T13:34:29Z (GMT). No. of bitstreams: 1 Isis da Costa Pinho.pdf: 4020024 bytes, checksum: e23e8e48a9a7db1bd90be0d18227c6d8 (MD5) Previous issue date: 2013-03-27 / Nenhuma / A pesquisa em educação mediada por computador sugere que a tecnologia tem um grande potencial para o ensino-aprendizagem de línguas dentro de uma perspectiva colaborativa, já que potencializa o uso da língua e da tecnologia como fatores de mediação de construção e compartilhamento do conhecimento. Nesse contexto, uma educação de línguas de qualidade deve explorar as potencialidades das ferramentas digitais na promoção da interação social, em que os aprendizes são desafiados a mobilizar e transformar seus recursos linguísticos para construir conhecimento sobre a língua enquanto se esforçam para fazer sentido na língua estrangeira (LE). Assim, esta pesquisa caracteriza-se por ser um estudo de caso que visa investigar a produção de estudantes de graduação em Letras em tarefas colaborativas em inglês como LE em ambiente virtual, focando a mediação no processo de aprendizagem. A fundamentação teórica utilizada consiste de princípios da teoria sociocultural vygotskiana, a teoria dos sistemas complexos, de estudos na área de informática na educação e a pesquisa na aquisição de segunda língua e língua estrangeira. Os participantes dessa pesquisa foram alunos de graduação de Letras/Inglês de uma universidade particular do sul do Brasil. A geração de dados ocorreu em três encontros no laboratório de informática realizados para complementar a disciplina de Inglês 3 com uma sequência de tarefas colaborativas de produção oral através de recursos multimídia e ferramentas digitais online. O espaço virtual utilizado foi o wiki online PBworks por permitir a interação colaborativa e o compartilhamento da produção entre todos seus usuários. As tarefas colaborativas envolveram discussões de vídeos curtos do Youtube em inglês como LE pelos aprendizes a partir de questões de interpretação através da ferramenta de conversa eletrônica Skype. Após cada tarefa, as duplas foram chamadas a ouvir a sua gravação e refletir sobre a sua produção no Skype, a tarefa e a sua aprendizagem, processo colaborativo que foi também gravado. Ainda, no final dos três encontros, os aprendizes responderam a um questionário que procurou investigar as suas percepções sobre as tarefas realizadas e a experiência de uso da tecnologia na aprendizagem da LE. A análise dos dados focou cinco fatores de mediação da aprendizagem de LE, quais sejam, a colaboração, o andaimento, a metafala, a tarefa e a tecnologia. Os resultados deste estudo apontam para os benefícios de tarefas colaborativas apoiadas pela tecnologia para a aprendizagem de inglês como LE ao promover um ambiente de intensa exploração, aplicação e modificação de língua apoiadas pela construção conjunta de conhecimento a partir do foco no erro como oportunidade de aprimoramento da produção. Além disso, observou-se que o uso da tecnologia para aprendizagem de línguas possibilitou que os estudantes visualizassem as possibilidades pedagógicas das ferramentas e recursos para a sua futura prática docente. Finalmente, esta pesquisa pretende prover dados e discussão para a melhoria da pesquisa em Linguística Aplicada, Aquisição de Segunda Língua e Língua Estrangeira e Aprendizagem de Línguas Mediada por Computador, somando-se a estudos sobre tarefas colaborativas sob a perspectiva da teoria sociocultural e da complexidade. / Research on computer-mediated education suggests that technology has a great potential for the teaching and learning of languages from a collaborative perspective, since it enhances the use of language and multimedia as mediational means of construction and sharing of knowledge. Within this context, a quality language education should exploit digital tools’ potentialities in fostering social interaction, in which the learners are challenged to mobilize and transform their linguistic resources to build knowledge about language while they struggle to make meaning in the foreign language. Thus, this research is a case study that aims to investigate the production of undergraduate students in collaborative tasks in English as a foreign language (EFL) in a virtual environment, focusing on the mediation in the learning process. The theoretical framework used in this study consists of vygotskian sociocultural theory principles of learning, complex systems theory, studies in the area of computers in education, and second language and foreign language acquisition reserch. Participants in this study were undergraduate students of Languages/English from a private university in southern Brazil. The data generation was carried out during three classes in the computer lab designed to complement the discipline of English 3 with a series of oral production collaborative tasks through online multimedia resources and digital tools. For the virtual space it was used PBworks wiki as it enables collaborative interaction and sharing of production among all its users. The collaborative tasks envolved EFL chat discussions of Youtube short videos by the learners in pairs based on comprehension questions over Skype. After each task, the dyads were asked to listen to their recordings and reflect on Skype upon their production, the task, and their learning, a collaborative process that was recorded too. Still, in the end of the three classes students answered a questionnaire designed to investigate their perception on the tasks done and the whole experience of using technology to learn a FL. Data analysis focused on five mediational factors of EFL learning, i. e. collaboration, scaffolding, metatalk, task and technology. The results of the present research point to the benefits of collaborative tasks for EFL learning as they fostered an environment of intense exploration, application and modification of language supported by the joint construction of knowledge from focus on error as an opportunity for production improvement. Moreover, it was observed that the use of technology for language learning allowed students to visualize the educational possibilities of tools and resources used for their future teaching practice. Finally, this research intends to provide data and discussion for the improvement of research in Applied Linguistics, Second and Foreign Language Acquisition and Computer-Mediated Language Learning, adding to studies on collaborative tasks from the perspectives of sociocultural and complex systems theory.

Large-scale and long-term planning imposes extensive requirements on governance efforts regardless of whether it involves public organisations, private organisations, or both. The proportions of such planning entangle many actors and stakeholders as system components within and around a complex system. These system components and conditions in a complex planning environment introduce a diverse variety of strategic objectives into the planning. This study investigates how strategic objectives can affect the governance of complex planning systems, particularly in the context of national critical infrastructure protection. For this purpose, this thesis concentrates on a national planning procedure, STYREL, which Sweden has recently implemented for the case of power shortages. This case involves various actors from the national, regional and local levels who act on behalf of both public and private organisations in a planning process with four-year intervals, and it thus constitutes a relevant subject for this study. The investigation entailed the collection of evidence from documents and interviews. First, publicly available Swedish documents regarding the case provided an understanding of the planning. Second, interviews with decision-makers who are entrusted with this planning at municipalities and county administrative boards as well as with a few planners from power grid providers offered a deeper comprehension of both the proceedings in practice and the strategic objectives involved in this complex system for planning of critical infrastructure protection. Particularly, the findings resulted in several conceptual models that demonstrate these understandings in more detail. A soft system model visualises the problem situation and contains several elements, such as the system components, interrelations and conditions. Moreover, a multi-level planning model specifies sources of uncertainty in the planning and decision-making process that are associated with an insufficient alignment of strategic objectives in the STYREL case. These decompositions of the Swedish planning environment – both horizontal and vertical – further enabled this study to identify significant parameters of the systemic conditions and strategic objectives involved in such complex planning environments that challenge their governance. The findings of this study suggest that the Swedish process is not yet fully developed. The investigation particularly indicates that a better alignment of strategic objectives is necessary to ensure a selection of adequate goals and means that advances the future usability of the produced plan, which in turn would legitimate and strengthen this complex planning process for critical infrastructure protection. / Storskalig och långvarig planering ställer höga krav på styrning. Detta gäller oavsett om offentliga eller privata organisationer, eller båda, är involverade. Omfattningen av en sådan planering engagerar många aktörer och intressenter som komponenter inom och omkring ett komplext system. Dessa komponenter samt deras villkor inbäddade i en komplex planeringsmiljö skapar en mångfald av strategiska målbilder som följer med in till planeringen. Denna studie undersöker därför hur strategiska målbilder kan påverka styrningen av komplexa planeringssystem, särskilt i kontexten av skyddet av kritisk infrastruktur i samhället. Undersökningen fokuserar på en nationell planeringsprocess, kallad STYREL, som avser beredskapsplanering för elbristsituationer och som implementerats i Sverige. Planeringsmiljön omkring STYREL är ett relevant studieobjekt eftersom den involverar många aktörer från nationell, regional och lokal nivå. Dessa aktörer representerar offentliga och privata organisationer i den planeringsprocess som genomförs med fyraårsintervaller. Under undersökningens gång har bevis samlats in från dokument och intervjustudier. Först har offentlig tillgängliga dokument om fallet skapat en förståelse om planeringen. Intervjuer med beslutsfattare som är ansvariga för STYREL-planeringen hos länsstyrelser, kommuner samt elnätsbolag har sedan genererat en ännu djupare förståelse. Detta gällande både förfaringssättet i praktiken och de strategiska målbilder som är involverade i detta komplexa system för planering av kritisk infrastruktur-skydd. Resultaten ledde i synnerhet till några konceptuella modeller vilka demonstrerar förståelserna på ett detaljerat sätt. En systemmodell visualiserar problemsituationen och innehåller flera element såsom systemkomponenter, relationer och villkor. En multinivå-planeringsmodell specificerar källor av osäkerhet i planerings- och beslutsprocessen vilka är associerade med en otillräcklig harmonisering av strategiska målbilder i STYREL fallet. Dekompositionerna av den svenska planeringsmiljön – både horisontellt och vertikalt – gjorde det möjligt att identifiera signifikanta parametrar av de systemiska villkor och strategiska målbilder som är involverade i dessa komplexa planeringsmiljöer och utmanar deras styrning. Resultaten av studien indikerar att den svenska processen inte är fullt utvecklat. Undersökningen visar att en bättre harmonisering av strategiska målbilder är nödvändig för att säkerställa ett urval av adekvata mål och medel som skulle utveckla den framtida användbarheten av den producerade planen. Denna skulle i sin tur legitimera och stärka den komplexa planeringsprocessen för skyddet av kritisk infrastruktur. Därtill kunde detta främja en målgruppsorienterad kommunikation om risker och relevanta åtgärder. / <p>Vid tidpunkten för framläggningen av avhandlingen var följande delarbeten opublicerade: delarbete 1 under granskning, delarbete 3 under granskning.</p><p>At the time of the defence the following papers were unpublished: paper 1 under review, paper 3 under review.</p>

Este trabalho está divido em duas partes. Na primeira apresentamos as funções logaritmo e exponencial generalizadas. A partir delas uma grande variedade de outras funções generalizadas pode ser obtida, permitindo uma formulação única dos comportamentos oscilatório, exponencial e lei de potência, característicos dos principais fenômenos físicos. Também mostramos que é possível generalizar a função densidade de probabilidade (pdf) exponencial estendida (stretched exponential) e, a partir dela, uma vasta gama de outras pdfs, que caracterizam os sistemas complexos em Física. As funções logaritmo e exponencial generalizadas também são úteis na generalização de vários modelos contínuos de crescimento em uma formulação única: o modelo de crescimento generalizado de Tsoullaris e Wallace. O mesmo pode ser feito para modelos discretos de crescimento, obtendo, como modelo mais geral, o -Ricker generalizado. Encerrando a primeira parte, mostramos que a pdf gaussiana generalizada (um caso particular da exponencial estendida generalizada) é a solução da equação de difusão não-linear, que caracteriza a caminhada determinista do turista. Na segunda parte deste trabalho é apresentada a caminhada do turista e suas duas versões originais: a determinista (CDT) e a estocástica (CET). A primeira delas é uma caminhada parcialmente autorrepulsiva, caracterizada por uma memória , em um meio desordenado multidimensional formado por N pontos. Em um ambiente unidimensional, ela apresenta uma transição entre uma exploração local e outra global, em um valor bem definido de memória 1 = log2N. Em sua versão estocástica (da qual a CDT é um caso particular), a dinâmica de movimentação é regida pela memória e pela temperatura T, responsável, em última instância, pelas probabilidades de deslocamento. Da mesma forma que a CDT, a CET também apresenta uma transição entre os regimes de exploração, caracterizada por uma memória e uma temperatura críticas e pela idade Np da caminhada (efeito de envelhecimento). Dada a dificuldade em tratar analiticamente a CET, introduzimos a caminhada estocástica modificada do turista (CEMT). Nesta versão, o parâmetro T passa a representar o alcance máximo de um passo da caminhada. Esta modificação permitiu tratar analiticamente a caminhada, sendo possível obter uma expressão analítica geral para a transição, em função dos parâmetros , T e Np. Estes resultados foram validados por experimentos numéricos. / The present work is splitted into two parts. In the first one we present the generalized logarithm and exponential functions. From them, a wide variety of other generalized functions can be obtained, that allow a unique formulation of oscillatory, exponential an power-law behaviors, that characterize physical phenomena. We also show that it is possible to generalize the stretched exponential probability density function (pdf) and, from there, a wide range of other pdfs that characterize complex systems in Physics. The generalized logarithm and exponential functions are also useful to generalize several continuous growth models into a single formulation: the generalized Tsoullaris and Wallace growth model. The same can be done for discrete growth models, getting, as more general model, the generalized -Ricker growth model. Concluding the first part, we show that the generalized Gaussian pdf (a special case of the generalized stretched exponential) is a solution of the nonlinear diffusion equation, which is a characteristic of deterministic tourist walk. In the second part we present the tourist walk and its two original versions: the deterministic one (DTW) and stochastic one (STW). The first one is a partially self-avoiding walk over a disordered multidimensional medium formed by N points and characterized by a memory . In a one-dimensional environment, it presents a transition from a local exploration to a global one at a well-defined memory value 1 = log2N. In its stochastic version (from which DTW is a particular case), the movement dynamics is ruled by the memory and a temperature T which is responsible by the displacement probabilities. Similar to DTW, STW also has a transition between exploration schemes, characterized by a critical memory and temperature and the walking age (Np) (aging effect). Due the difficulty on analytical treatment of the CET, we introduced the modified stochastic tourist walk (MSTW). In this version, the parameter T plays the role of a maximum distance of one walking step. This modification allowed us to treat analytically the walk, being possible to obtain a general analytical expression for the transition, as function to the parameters , T and Np. These results were validated by numerical experiments.

A evolução tecnológica das redes de telecomunicações sem fio permite que organizações de redes mais inteligentes sejam vislumbradas. É possível imaginar um sistema de telefonia formado por dispositivos móveis autônomos que não necessite de nenhuma infraestrutura pré-estabelecida para trocar informações com seus vizinhos, de acordo com o alcance do raio de transmissão. Assim, as informações poderiam ser repassadas de nó em nó, formando uma rede de múltiplos saltos. A ausência de uma entidade central também poderia melhorar a tolerância a falhas do sistema, principalmente por gerar uma redundância de caminhos possíveis entre os nós. Analisamos o desempenho desse sistema em diferentes cenários e a sensibilidade à variação de parâmetros como o raio de transmissão, interferências, a quantidade de nós e número de saltos máximo permitido (TTL), e testamos estratégias de comunicação com raio fixo, raio variável, número de vizinhos mínimo e etc., através de modelagem e simulação baseada em agentes. De maneira geral, a estratégia de transmissão com raio variável apresentou a melhor taxa de mensagens recebidas e a menor média de saltos até o destino, porém com maior nível de energia do sistema. A estratégia de raio fixo apresentou a menor energia total gasta pelo sistema para enviar as mensagens, porém, com uma taxa menor de mensagens recebidas. Além disso, avaliamos que as principais causas de perdas de pacotes estão associadas com o aumento da mobilidade, a redução do TTL e as interferências, sendo que cada uma contribui mais ou menos de acordo com o cenário estudado. / The technological development of Wireless Networks leads to more intelligent networks structures. One can imagine a mobile data system consisting of autonomous mobile devices that do not require any pre-established infrastructure to exchange information one with another, limited mainly by the transmission radius. Thus, data could be forwarded from node to node, forming a multihop network. The absence of a central entity could also improve fault tolerance by allowing redundant paths for nodes to communicate. We analyzed the performance of the system in different scenarios and system behavior regarding parameters variations such as transmission radius, interferences, the number of nodes and maximum allowed number of hops (TTL), and tested communication strategies with fixed radius, variable radius, minimum number of neighbors to transmit, etc., through modeling and simulation-based agents. In general, variable radius strategy had the best rate of incoming messages and the lowest average number of hops to the destination. However it presented the higher level of system energy. In one hand, fixed radius strategy presented the lowest total energy expended by the system to send messages, but, in the other hand, the rate of incoming messages was lower. Furthermore, we discovered the main causes of packet losses are associated with increased mobility, reducing the TTL and interference, each of which contributes more or less in accordance with the scenario.

Swarm robotics is the study of developing and controlling large groups of robots. Collectives of robots possess advantages over single robots such as being robust to mission failures due to single-robot errors. Experimental research in swarm robotics is currently limited by swarm robotic technology. Current swarm robotic systems are either small groups of sophisticated robots or large groups of simple robots due to manufacturing overhead, functionality-cost dependencies, and their need to avoid collisions, amongst others. It is therefore useful to develop a swarm robotic system that is easy to manufacture, that utilises its sensors beyond standard usage, and that allows for physical interactions. In this work, I introduce a new type of low-friction locomotion and show its first implementation in the HoverBot system. The HoverBot system consists of an air-levitation and magnet table, and a HoverBot agent. HoverBots are levitating circuit boards which are equipped with an array of planar coils and a Hall-effect sensor. HoverBot uses its coils to pull itself towards magnetic anchors that are embedded into a levitation table. These robots consist of a Printed Circuit Board (PCB), surface mount components, and a battery. HoverBots are easily manufacturable, robots can be ordered populated; the assembly consists of plugging in a battery to a robot. I demonstrate how HoverBot's low-cost hardware can be used beyond its standard functionality. HoverBot's magnetic field readouts from its Hall-effect sensor can be associated with successful movement, robot rotation and collision measurands. I build a time series classifier based on these magnetic field readouts, I modify and apply signal processing techniques to enable the online classification of the time-variant magnetic field measurements on HoverBot's low-cost microcontroller. This method allows HoverBot to detect rotations, successful movements, and collisions by utilising readouts from its single Hall-effect sensor. I discuss how this classification method could be applied to other sensors and demonstrate how HoverBots can utilise their classifier to create an occupancy grid map. HoverBots use their multi-functional sensing capabilities to determine whether they moved successfully or collided with a static object to map their environment. HoverBots execute an "explore-and-return-to-nest" strategy to deal with their sensor and locomotion noise. Each robot is assigned to a nest (landmark); robots leave their nests, move n steps, return and share their observations. Over time, a group of four HoverBots collectively builds a probabilistic belief over its environment. In summary, I build manufacturable swarm robots that detect collisions through a time series classifier and map their environment by colliding with their surroundings. My work on swarm robotic technology pushes swarm robotics research towards studies on collision-dependent behaviours, a research niche that has been barely studied. Collision events occur more often in dense areas and/or large groups, circumstances that swarm robots experience. Large groups of robots with collision-dependent behaviours could become a research tool to help invent and test novel distributed algorithms, to understand the dependencies between local to global (emergent) behaviours and more generally the science of complex systems. Such studies could become tremendously useful for the execution of large-scale swarm applications such as the search and rescue of survivors after a natural disaster.

Die Doktorarbeit untersucht, wie sich Mensch-Umwelt-Interaktionen am Beispiel von Abholzung und Landnutzungsänderungen im Amazonas analysieren und modellieren lassen. Die Abholzung tropischer Wälder bedroht die Stabilität artenreicher Ökosysteme, lokaler Wettergeschehen und des globalen Klimas. Drei Hauptteile erforschen das Thema mit Konzepten der theoretischen Physik und Netzwerktheorie. Der erste Teil gibt einen kritischen Überblick über Modellansätze, die Entscheidungen und menschliches Verhalten beschreiben. Agentenbasierte Netzwerkmodelle ergeben sich als vielversprechender Ansatz um sozial-ökologische Systeme zu modellieren. Der zweite Teil identifiziert Muster in satellitengestützten Landbedeckungsdaten im brasilianischen Amazonas. Basierend auf der Theorie der Markov-Ketten werden Übergangsraten zwischen verschiedenen Typen von Landbedeckung berechnet und Übergangsmatrizen für Teilgebiete mit Clusteralgorithmen verglichen. Angrenzende Teilgebiete weisen ähnliche Übergänge auf. Die identifizierten Cluster decken sich mit Erkenntnissen aus Feldstudien. Auf Grundlage der geschätzten Übergangsrate ergeben sich Projektionen für die Entwicklung der Landbedeckungsanteile. Der dritte Teil entwickelt ein agentenbasiertes Modell um zu untersuchen, unter welchen Bedingungen die Intensivierung der Viehhaltung im Amazonas die Abholzung reduzieren kann. Das Modell kombiniert ökologische, ökonomische und soziale Prozesse und modelliert Landnutzungsstrategien mit Heuristiken. Die Modellanalyse zeigt, dass eine Intensivierung die Abholzung nur dann verringert, wenn der lokale Viehmarkt saturiert. Unter anderen ökonomischen Bedingungen kann Intensivierung die Abholzung erhöhen. Die Arbeit demonstriert, dass eine Kombination von Methoden aus der Theorie komplexer Systeme mit sozialwissenschaftlichen Theorien zu einem besseren Verständnis der emergenten Dynamik sozial-ökologischer Systeme führen kann – eine Grundvoraussetzung, um solche Systeme nachhaltig zu bewirtschaften. / This thesis investigates how to model and analyze human-nature interactions using the example of deforestation and land-use change in the Brazilian Amazon. Deforestation of tropical forests threatens the stability of species-rich ecosystems, local weather patterns, and global climate. The three main parts of the thesis study different aspects of this topic using concepts from theoretical physics and network theory. The first part reviews modeling approaches to human decision making and behavior. From the review, networked agent-based models emerge as promising tools to capture the dynamics of social-ecological systems such as the land system. The second part of the thesis combines Markov-chain and cluster analyses to detect patterns in satellite-derived land-cover maps of the Brazilian Amazon. I compute transition rates between different land-cover types and apply clustering algorithms to find spatial patterns. The analysis shows that neighboring subregions undergo similar transitions and identifies clusters corresponding to findings from field surveys. Markov-chain models, parameterized with the transition rates, are used to compute land-cover projections. In the third part, I develop an agent-based model to investigate under which conditions the intensification of cattle ranching can reduce deforestation in the Amazon. The model captures stylized environmental, economic, as well as social processes, and uses heuristic decision theory to represent different land management strategies. A detailed analysis reveals that fast intensification can only lower deforestation rates if local cattle markets saturate. Under other economic conditions intensification may increase deforestation. The contributions of this thesis demonstrate that combining modeling tools from complexity science with social-science theories allow better understanding the emergent dynamics of social-ecological systems, which is a prerequisite for their sustainable management.

[Truncated abstract] The application of reductionism, breaking down problems to simpler components that can be solved and then aggregating the results, is one of the bases of classical science. However, living organisms, ecosystems, social and economic structures are complex systems, characterised by non-linear interactions between their elements and exhibit emergent properties that are not directly traceable to their components. Sustainability assessment frameworks oversimplify system interactions, achieving limited predictive capacity and causing managerial behavior that may reduce system's ability to adapt to external disturbance. Intrigued by the importance of complexity, we explore the central theme of how complex thinking can influence the understanding and progress towards sustainability. The purpose is to conceptualize the relationship of key terms (such as sustainability, functionality and resilience), and consecutively develop new or adjust existing sustainability frameworks to take into account complex systems interactions. We aim at developing theory and frameworks that can be used to raise awareness of the pitfalls of the growth paradigm and direct towards modest positions when managing complex systems. We seek to define the structural elements that influence system adaptive capacity, allowing identification of early signs of system rigidity or vulnerability and the development of knowledge and techniques that can improve our predictive and managerial ability. The focus has been on a variety of system scales and dynamics. At the collective community level, a number of stakeholder engagement practices and frameworks are currently available. However, there is limited awareness of the complexity challenges among stakeholders, who are commonly directed to a triple bottom line analysis aiming at maximizing a combination of outputs. An attempt is conducted to measure the functionality of the processes underlying a standing stock, in contrast to sustainability measures that only assess the variations of the standing stock itself. We develop the Index of Sustainable Functionality (ISF), a framework for the assessment of complex systems interactions within a large-scale geographic domain and apply it to the State of Western Australia. '...' Finally, we focus on smaller systems scales and develop a methodology for the calculation of Product Ecological Footprint (PEF) including elements from the accounting method of activity based costing. We calculate PEF for three apple production systems and identify significant differences from first stage calculations within the same industry. Cross-industry application will provide a practical way to link individuals' consumption with their ecological impact, reduce misperceptions of products' ecological impacts and develop a market-driven approach to internalizing environmental externalities. At the firm level PEF can be compared with investment costs, resulting in the opportunity to optimize both functions of financial cost and ecological impact in decision making. We have developed methods for incorporating complexity in sustainability assessment frameworks. Further work is required in testing and validating these methodologies at multiple system scales and conditions. Integrating such tools in decision making mechanisms will enhance long-term management of socioecological systems performance.