This dissertation examines human settlement-size variation through the lens of hunter-gatherer archaeology. Research article 1 presents an analysis of prehistoric hunter-gatherer settlement patterns from a wide range of environmental contexts and in the absence of socioeconomic complexity. Hunter-gather settlement size variation is found to exhibit heavy-tailed statistical structure that is consistent with the statistical structure of modern settlement-size variation, supporting claims that socioeconomic complexity is not requisite for the formation of so-called settlement-size hierarchies in human societies. Following insights from hunter-gatherer anthropology, complex systems research, and ecology, research article 2 proposes that the structure of hunter-gatherer site-size variation is an emergent property of obligate tool use among mobile hunter-gatherers. As materials are moved, modified, and deposited on the landscape, they effectively subsidize the costs of future land use at those locations, which results in additional material deposition, attracting future use, and so on. Using an agent-based model, it is demonstrated that this recursive niche-construction behavior is sufficient to generate the heavy-tailed property of hunter-gatherer site-size variation. The working model is then used to predict other dimensions of hunter-gatherer settlement structure related to artifact clustering and site occupation histories. Research articles 2 and 3 present test results based on Late Archaic Period (7,000-5,000 B.P.) settlement patterns in the Lake Titicaca Basin, Peru. Good agreement is found between the predictions and empirical observations suggesting that ecological niche construction may have played a significant role in structuring hunter-gatherer mobility and land use, which in turn may have created a context for emergent settlement hierarchies.

This research explores how individuals make sense of their own lived experiences of health through the sharing of their stories and how the collectively shared meaning can be used to identify core values fundamental to sustaining a flourishing Canadian health care system. This study considers health care to be a complex system with inherent unpredictability where ideas for values-based sustainability must be given freedom to emerge. At the Kelowna Dialogue on Health, 29 individuals with diverse health care experiences and perspectives participated in a one-day Appreciative Inquiry (AI) conversation. During the seven-hour dialogue, the affirmative topics of compassion, collaboration, and personal responsibility emerged and a full AI 4-D cycle of discovery, dream, design, and destiny was performed. The delivery of these affirmative topics into actionable ideas that will be communicated in the public sphere through digital media will hopefully empower the participants, both health care providers and recipients, to strive for personalized compassionate health care

Innovation is defined as the introduction of new things or methods. In the history of human society, progress and cultural evolution occurred as a consequence of innovation processes. Typically changes proposed by a restricted number of peoples became widely adopted innovations as soon as a broad consensus formed around their adoption. In this thesis, we explore the role of innovators as potentially influential individuals in our society. Studying their behaviour is crucial to understand what are the factors that drove their decision in the process of becoming influential. In particular, here we uncover the importance of cultural attractors as cities where strong akin communities are present. Our approach involves the use of Wikipedia as a source for historical mobility data to model the migration patterns of globally relevant innovators. While here we study mobility on a broad range of different disciplines where different innovators gave their contributions, we also focus on a smaller and more modern system. Historical innovators are easily identified and discerned from uninfluential ones thanks to the wisdom of the time. However, due to the scarce availability of individual historical data, we point our attention to more recent versions of innovators: code developer. The flourishment of the digital era made code developers at the very centre of our global economy. We study this coupled system as a representative example of the interaction between innovators and the economy. Indeed, a significant, non-trivial interaction is found among the two worlds. More in general, in this thesis we highlight the relevance of innovators in shaping human collective responses. Our results reveal that innovators play a major role both individually and collectively at different scales. We provide measures of these effects (i) by looking at how innovator communities construct the attractiveness of a city and (ii) by studying how individual contributions in the innovation domain can dramatically affect financial behaviour also at short time scales. Our result expands the evidence of the need for a new research dimension, where human behaviour is studied as a complex system moving over an intricate network of intertwined interactions.

Many who study complex systems believe that the complexity we observe in the world around us is frequently the product of a large number of interactions between components following a simple rule. However, the task of discerning the rule governing the evolution of any given system is often quite difficult, requiring intuition, guesswork, and a great deal of expertise in that domain. To circumvent this issue, researchers have considered the inverse problem where one searches among many candidate rules to reveal those producing interesting behavior. This approach has its own challenges because the search space grows exponentially and interesting behavior is rare and difficult to rigorously define. Therefore, the contribution of this work includes tools and techniques for searching for dimer automaton rules that exhibit self-organization (the transformation of disorder into structure in the absence of centralized control). Dimer automata are simple, discrete, asynchronous rewriting systems that operate over the edges of an arbitrary graph. Specifically, these contributions include a number of novel, surprising, and useful applications of dimer automata, practical methods for measuring self-organization, advanced techniques for searching for dimer automaton rules, and two efficient GPU parallelizations of dimer automata to make searching and simulation more tractable. / Ph. D.

There is a potential as well as a growing interest amongst researchers to utilise simulation in optimising maintenance systems. The state of the art in simulation-based optimisation of maintenance was established by systematically classifying the published literature and outlining main trends in modelling and optimising maintenance systems. In general, approaches to optimise maintenance varied significantly in the literature. Overall, these studies highlight the need for a framework that unifies the approach to optimising maintenance systems. Framework requirements were established through two main sources of published research. Surveys on maintenance simulation optimisation were examined to document comments on the approaches authors follow while optimising maintenance systems. In addition, advanced and future maintenance strategies were documented to ensure it can be accommodated in the proposed framework. The proposed framework was developed using a standard flowchart tool due to its familiarity and ability to depict decision structures clearly. It provides a systematic methodology that details the steps required to connect the simulation model to an optimisation engine. Not only it provides guidance in terms of formulating the optimal problem for the maintenance system at hand but it also provides support and assistance in defining the optimisation scope and investigating applicable maintenance strategies. Additionally, it considers current issues relating to maintenance systems both in research and in practice such as uncertainty, complexity and multi-objective optimisation. The proposed framework cannot be applied using existing approaches for modelling maintenance. Existing modelling approaches using simulation have a number of limitations: The maintenance system is modelled separately from other inter-related systems such as production and spare parts logistics. In addition, these approaches are used to model one maintenance strategy only. A novel approach for modelling maintenance using Discrete Event Simulation is proposed. The proposed approach enables the modelling of interactions amongst various maintenance strategies and their effects on the assets in non-identical multi-unit systems. Using the proposed framework and modelling approach, simulation-based optimisation was conducted on an academic case and two industrial cases that are varied in terms of sector, size, number of manufacturing processes and level of maintenance documentation. Following the structured framework enabled discussing and selecting the suitable optimisation scope and applicable maintenance strategies as well as formulating a customised optimal problem for each case. The results of the study suggest that over-looking the optimisation of maintenance strategies may lead to sub-optimal solutions. In addition, this research provides insights for non-conflicting objectives in maintenance systems.

The analysis of large disordered complex networks has recently received enormous attention motivated by both academic and commercial interest. The most important results in this discipline have come from the analysis of stochastic models which mimic the growth and evolution of real networks as they change over time. The purpose of this thesis is to introduce various novel processes which dictate the development of a network on a small scale, and use techniques learned from statistical physics to derive the dynamical and structural properties of the network on the macroscopic scale. We introduce each model as a set of mechanisms determining how a network changes over a small period in time, from these rules we derive several topological properties of the network after many iterations, most notably the degree distribution. 1. In the rst mechanism, nodes are introduced and linked to older nodes in the network in such a way as to create triangles and maintain a high level of clustering. The mechanism resembles the growth of a citation network and we demonstrate analytically that the mechanism introduced su ces to explain the power-law form commonly found in citation distributions. 2. The second mechanism involves edge rewiring processes - detaching one end of an edge and reattaching it, either to a random node anywhere in the network or to one selected locally. 3. We analyse a variety of processes based around a novel fragmentation mechanism. 4. The nal model concerns the problem of nding the electrical resistance across a network. The network grows as a random tree, as it grows the distribution of resistance converges towards a steady state solution. We nd an application of the relatively recent concept of a random Fibonacci sequence in deriving the rate of convergence of the mean.

<p align="justify">Ce travail consiste à étudier des systèmes constitués par un grand nombre de grains, auxquels de l’énergie cinétique est fournie, et à étudier leurs similarités et leurs différences avec des fluides traditionnels. Je me concentre principalement sur la nature de non-équilibre de ces fluides granulaires, en montrant que, même si les méthodes de méchanique statistique y sont applicables, leurs propriétés sont très différentes de celles de systèmes à l’équilibre ou proches de l’équilibre :</p> <ul><li>Les fluides granulaires présentent des phénomènes de transport qui n’ont pas d’équivalent dans des fluides moléculaires, tels qu’un couplage spécifique entre flux de chaleur et gradient de densité. <li>Leur distribution de vitesse est en général différente de la distribution de Maxwell-Boltzmann, et présente une surpopulation pour les grandes vitesses. <li>Dans le cas de mélanges, différentes espèces de grains sont en général caractérisées par des énergies cinétiques différentes, i.e. ces systèmes sont sujet à une non-equipartition de leur énergie. <li>Ces fluides ont tendance à former des inhomogénéités spatiales spontanément. Cette propriété est illustrée en étudiant l’expérience du Demon de Maxwell appliquée aux systèmes granulaires.</ul> <p align="justify">Chacune de ces particularités est discutée en détail dans des chapitres distincts, où l’on applique différentes méthodes de méchanique statistique (équation de Boltzmann, transition de phase, mean field models…) et où l’on vérifie les prédictions théoriques par simulations numériques (MD, Monte Carlo…).</p>

O presente trabalho explora como duas abordagens gerais da complexidade - ciências da complexidade e pensamento complexo - estão influenciando e podem vir a influenciar a gestão de sistemas organizacionais produtivos. Constata-se um aumento de publicações que relacionam a Complexidade à Gestão. Por meio de análise de conteúdo de trabalhos acadêmicos internacionais e nacionais identifica-se uma diminuição na ênfase inicial sobre teoria do caos e fractais e uma tendência recente na exploração da dinâmica de redes, ao mesmo tempo em que modelos baseados em agentes são cada vez mais explorados (associados à idéia de sistemas adaptativos complexos - SAC). Na produção nacional nota-se também a presença de idéias de cunho mais filosófico relacionadas à complexidade, notoriamente as do pensamento complexo do francês Edgar Morin. Com base na história do pensamento científico são identificados fundamentos do paradigma mecanicista dominante e fatores que estão contribuindo para transição de fase desse paradigma, relacionados ao aumento de complexidade na ciência e ao surgimento das ciências da complexidade. Estas ciências são caracterizadas como um processo evolutivo da Teoria Geral de Sistemas e possuem uma diversidade de contribuições em evolução, as quais têm sido utilizadas como referência para teorias e modelos de gestão de sistemas organizacionais produtivos. Explora-se a importância do desenvolvimento de um pensamento \'mais\' complexo e sua relação com a gestão. Apresenta-se uma discussão crítica sobre o uso de conceitos relacionados à complexidade, ressaltando-se que não existe um modelo de uma \'Teoria Geral da Complexidade\'. Avalia-se como esses conceitos são e podem vir a ser aplicados na Engenharia de Produção, por meio de: estudo de caso sobre o desenvolvimento e implementação de um sistema auto-organizado de solução de problemas em uma empresa de Agrobusiness; análise crítica, sob a ótica da complexidade, de trabalhos da área; e apresentação de propostas teóricas para aplicação do pensamento complexo. Conclui-se que as perspectivas da complexidade estão diretamente relacionadas a uma mudança de paradigma - na abrangência de um supra-paradigma, nos moldes de Kuhn - que passou do seu ponto de retorno, e que tais perspectivas afetarão cada vez mais a gestão de sistemas produtivos. / The present work explores how two general approaches of complexity - complexity sciences and complex thought - are influencing and may come to influence productive organizational systems management. An increase in publications relating Complexity to Management can be observed. By analyzing the content of international and Brazilian academic works, a decrease in the initial emphasis on the chaos theory and fractals is identified as well as a recent trend in the exploration of networks dynamics, at the same time at which models based on agents are more and more explored (associated to the idea of complex adaptative systems - CAS). In the Brazilian production, also noticed is the presence of ideas of a more philosophical characteristic related to complexity, notoriously those of complex thought by the French Edgar Morin. Based on the history of scientific thought, foundations of the dominant mechanicist paradigm are identified as well as factors that are contributing to this paradigm phase transition, concerning the increase in complexity in science and to the emergence of complexity sciences. These sciences are characterized as an evolutive process of the General Theory of Systems and count on a wide range of contributions in evolution, which have been used as a reference for theories and models of productive organizational systems management. The importance of the development of a \'more\' complex thought and its relationship with management are explored. A critical discussion is presented on the use of concepts related to complexity, pointing out that there is not a model for a \'General Theory of Complexity\'. How these concepts are and may come to be applied in Production Engineering is evaluated, by means of: case study on the development and implementation of a problem-solving self-organized system in an Agribusiness company; critical analysis, under the complexity view, of works in the area; and presentation of theoretical proposals for applying complex thought. It is concluded that the perspectives of complexity are directly related to a change in paradigm - in the comprehensiveness of a supra-paradigm, following Kuhn\'s models - which went beyond its turning point, and that these perspectives will more and more affect productive systems management.

Tourism does not operate in a predictable and mechanistic environment and is influenced by unpredictable circumstances. Influences include underlying values and perceptions keeping the system unpredictable and dynamic. Tourism that utilises natural resources is exposed to the additional unpredictability of natural changes and activities and/or decisions of other stakeholders. Tourism research generally adopts reductionist approaches and has not effectively understood tourism as a stakeholder within a complex system of stakeholders. Reductionist approaches have led to interpretations of sustainable tourism development being highly focused and sector specific limiting understanding of the complex systems in which tourism operates and resulting in narrow perspectives. To understand underlying elements influencing the system, a new paradigm is required.

Any computation is facilitated by some physical process, and the observable quantities of any physical process can be viewed as a computation. These close ties suggest that the study of what universal computers are capable of may lead to additional insight about the physical universe, and vice versa. In his thesis, we explore three lines of research that are linked to this central theme. The first partition shows how notions of non-computability and undecidability eventually led to evidence of emergence, the concept that even if a ‘theory of everything’ governing all microscopic interactions were discovered, the understanding of macroscopic order is likely to require additional insights. The second partition proposes a physically motivated model of computation that relates quantum complexity, quantum optimal control, and Riemannian geometry. Thus insights in any one of these disciplines could also lead to insights in the others. The remainder of this partition explores a simple application of these relations. The final partition proposes a model of quantum computation that generalizes measurement based computation to continuous variables. We outline its optical implementation, whereby any computation can be performed by single mode measurements on a resource state that can be prepared by passing a collection of squeezed states through a beamsplitter network.