The ability to probe many-particle systems on a microscopic level has revolutionized the way we do statistical physics. As computational capabilities continue to grow exponentially, larger and more complex systems come within reach of microscopic analysis. In the field of network growth, the classical model has given way to competitive processes, in which networks are guided by some criteria at every step of their formation. We develop and analyze a new competitive growth process that permits intervention on growing networks using only local properties of the network when evaluating how to add new connections. We establish the critical behavior of this new method and explore potential uses in guiding the development of real-world networks. The classical system of electrons diffusing within a conductor similarly permits a microscopic analysis where, to date, studies of the macroscopic properties have dominated the literature. In order to extend our understanding of the theory that governs this diffusion—the fluctuation-dissipation theorem—we construct a physical model of the Johnson-Nyquist system of electrons embedded in the bulk of a conductor. Constructing the model involves deriving how the motion of each individual electron comes about via scattering processes in the conductor, then connecting this collective motion to the macroscopic observables of voltage and current that define Johnson-Nyquist noise. Once the equilibrium properties have been fully realized, an external perturbation can be applied in order to probe the behavior of the model as it deviates away from equilibrium. In much the same way that competitive network growth revolutionized classical network theory, we aim to establish a model which can guide future research into nonequilibrium fluctuation-dissipation by providing a method for interacting with the system in a precise and well-controlled manner as it evolves over time. This model is presented in its present form in Chapter 3. Chapter 2, which covers this work, has been published in Physical Review E as a Rapid Communication [1]. The writing and analysis were performed by me as the primary author. Eric Corwin and Georgios Tsekenis are listed as co-authors for their contribution to the analysis and for advisement on the work. This dissertation includes previously published and unpublished co-authored material.

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Today's supply chains face increasing volatility on many fronts. From the shop-floor where machines break and suppliers fail to the boardrooms where unanticipated price inflation erodes profi tability. Turbulence is the new normal. To remain competitive and weather these (daily) storms, supply chains need to move away from an effi ciency mindset towards a resilience mindset. For over a little more than a decade industry and academia have awakened to this reality. Academic literature and case studies show that there is no longer a shortage of resilience strategies and designs. Unfortunately, industry still lacks the tools with which to assess and evaluate the effectiveness of such strategies and designs. Without the ability to quantify the benefi t it is impossible to motivate the cost. This thesis adds one piece to the puzzle of quantifying supply chain vulnerability. Speci fically, it focussed on supply chains within urban areas. It addresses the question: "How does a supply chain's network design (internal con figuration) and its dependence on the underlying road network (external circumstances) make it more or less vulnerable to disruptions of the road network?" Multilayered Complex Network Theory (CNT) held promise as a modelling approach that could capture the complexity of the dependence between a logical supply chain network and the physical road network that underpins it. This approach addressed two research gaps in complex network theory applications. In the supply chain arena CNT applications have reaped many benefi ts but the majority of studies regarded single-layer networks that model only supply chain relations. There were no studies found where the dependence of supply chain layers on underlying physical infrastructure was modelled in a multilayered manner. Road network applications offered many more multilayered applications but these primarily focussed on passenger transport, not freight transport. The first artefact developed in the thesis was a multilayered complex network formulation representing a logical (supply chain) layer placed on a physical (road infrastructure) layer. The individual layers had predefi ned network characteristics and on their own could not hint at the inherent vulnerability that the system as a whole might have. From the multilayered formulation, the collection of shortest paths emerged. This is the collection of all shortest path alternatives within a network. The collection of shortest paths is the unique fingerprint of each multilayered network instance. The key to understanding vulnerability lies within the characteristics of the collection of shortest paths. Three standard supply chain network archetypes were de fined namely the Fully Connected (FC), Single Hub (SH) and Double Hub (DH) archetypes. A sample of 500 theoretical multilayered network instances was generated for each archetype. These theoretical instances were subjected to three link-based progressive targeted disruption simulations to study the vulnerability characteristics of the collection of shortest paths. Two of the simulations used relative link betweenness to prioritise the disruptions while the third used the concept of network skeletons as captured by link salience. The results from these simulations showed that the link betweenness strategies were far more effective than the link salience strategy. From these results three aspects of vulnerability were identifi ed. Redundancy quantifi es the number of alternative shortest paths available to an instance. Overlap measures to what degree the shortest path sets of an instance overlap and have road segments in common. Effi ciency step-change is a measure of the magnitude of the "shock" absorbed by the shortest paths of an instance during a disruption. For each of these aspects one or more metrics were defi ned. This suite of vulnerability metrics is the second artefact produced by the thesis. The design of the artefacts itself, although novel, was not considered research. It is the insights derived during analysis of the artefacts' performance that contributes to the body of knowledge. Link-based progressive random disturbance simulations were used to assess the ability of the vulnerability metrics to quantify supply chain vulnerability. It was found that none of the de fined vulnerability aspects are good stand-alone predictors of vulnerability. The multilayered nature and random disturbance protocol result in vulnerability being more multi-faceted than initially imagined. Nonetheless, the formulation of the multilayered network proved useful and intuitive and even though the vulnerability metrics fail as predictors they still succeed in capturing shortest path phenomena that would lead to vulnerability under non-random protocols. To validate the fi ndings from the theoretical instances, link-based random disturbance simulations were executed on 191 case study instances. These instances were extracted from real-life data in three urban areas in South Africa, namely Gauteng Province (GT), City of Cape Town (CoCT) and eThekwini Metropolitan Municipality (ET). The case study instances showed marked deviations from the assumptions underlying the theoretical instances. Despite these differences, the multilayered formulation still enables the quanti fication of the relationship between supply chain structure and road infrastructure. The performance of the vulnerability metrics in the case study corroborates the findings from the theoretical instances. Although the suite of vulnerability metrics was unsuccessful in quantifying or predicting vulnerability in both the theoretical and case study instances, the rationale behind their development is sound. Future work that will result in more effective metrics is outlined in this thesis. On the one hand the development of a more realistic disruption strategy is suggested. Road network disruptions are neither completely random nor specifi cally targeted. Important segments with greater tra ffic loads are more likely to be disrupted, but the reality is that disruptions such as accidents, equipment failure or road maintenance could really occur anywhere on the network. A more realistic disruption strategy would lie somewhere on the continuum between targeted and random disruptions. Other future work suggests the refi nement of both artefacts by incorporating link weights in both the logical and physical layers. An unanticipated fi nding from this thesis is that future research in the fi eld may be expedited if theory-building emanates from real-life empirical networks as opposed to theoretically generated networks. Expanding the scope of the case study, characterising the true network archetypes found in practice and increasing the number of case study samples is a high priority for future work. / Thesis (PhD)--University of Pretoria, 2018. / National Research Foundation of South Africa (Grant UID: 105519). Partial funding of doctoral research. / Industrial and Systems Engineering / PhD / Unrestricted

Conserving biodiversity in human-dominated landscapes requires protecting networks of ecological reserves and managing the intervening matrix to maintain the potential for species to move among them. This dissertation provides original insights towards (1) identifying areas for protection in reserves that are critical to maintain biodiversity and (2) assessing the potential for species' movements among habitat patches in a reserve network. I develop and test methods that will facilitate conservation planning to promote viable, resilient populations through time. The first part of this dissertation tests and develops reserve selection strategies that protect either a single focal species in a dynamic landscape or multiple interacting species in a static landscape. Using a simulation model of boreal forest dynamics, I test the effectiveness of static and dynamic reserves to maintain spatial habitat requirements of a focal species, American Marten (Martes americana). Dynamic reserves improved upon static reserves but re-locating reserves was constrained by fragmentation of the matrix. Management of the spatial and temporal distribution of land-uses in the matrix will therefore be essential to retain options for re-locating reserves in the future. Additionally, to include essential consumer-resource interactions into reserve selection, a new algorithm is presented for American marten and its two primary prey species. The inclusion of their interaction had the benefit t of producing spatially aggregated reserves based on functional species requirements. The second part of this dissertation evaluates and synthesizes the network-theoretic approach to quantify connectivity among habitat patches or reserves embedded within spatially heterogeneous landscapes. I conduct a sensitivity analysis of network-theoretic connectivity analyses that derive least-cost movement behavior from the underlying cost surface which describes the relative ecological costs of dispersing through different landcover types. Landscape structure is shown to aff ect how sensitive least-cost graph connectivity assessments are to the quality (relative cost values) of landcover types. I develop a conceptual framework to classify network connectivity statistics based on the component of habitat connectivity that they quantify and the level within the network to which they can be applied. Together, the combination of reserve design and network connectivity analyses provide complementary insights to inform spatial planning decisions for conservation.

Conserving biodiversity in human-dominated landscapes requires protecting networks of ecological reserves and managing the intervening matrix to maintain the potential for species to move among them. This dissertation provides original insights towards (1) identifying areas for protection in reserves that are critical to maintain biodiversity and (2) assessing the potential for species' movements among habitat patches in a reserve network. I develop and test methods that will facilitate conservation planning to promote viable, resilient populations through time. The first part of this dissertation tests and develops reserve selection strategies that protect either a single focal species in a dynamic landscape or multiple interacting species in a static landscape. Using a simulation model of boreal forest dynamics, I test the effectiveness of static and dynamic reserves to maintain spatial habitat requirements of a focal species, American Marten (Martes americana). Dynamic reserves improved upon static reserves but re-locating reserves was constrained by fragmentation of the matrix. Management of the spatial and temporal distribution of land-uses in the matrix will therefore be essential to retain options for re-locating reserves in the future. Additionally, to include essential consumer-resource interactions into reserve selection, a new algorithm is presented for American marten and its two primary prey species. The inclusion of their interaction had the benefit t of producing spatially aggregated reserves based on functional species requirements. The second part of this dissertation evaluates and synthesizes the network-theoretic approach to quantify connectivity among habitat patches or reserves embedded within spatially heterogeneous landscapes. I conduct a sensitivity analysis of network-theoretic connectivity analyses that derive least-cost movement behavior from the underlying cost surface which describes the relative ecological costs of dispersing through different landcover types. Landscape structure is shown to aff ect how sensitive least-cost graph connectivity assessments are to the quality (relative cost values) of landcover types. I develop a conceptual framework to classify network connectivity statistics based on the component of habitat connectivity that they quantify and the level within the network to which they can be applied. Together, the combination of reserve design and network connectivity analyses provide complementary insights to inform spatial planning decisions for conservation.

Thesis (Ph.D.) - University of St Andrews, April 2009.

Hierarkier har funnits under en lång tid och är för många en självklarhet inom organisationer. Vi vill i denna uppsats undersöka tre organisationer i Sverige, som menar att de utmanar den hierarkiska strukturen genom att de inte har några chefer. Syftet med uppsatsen är att öka kunskapen om dessa organisationer genom att undersöka hur beslut tas och färdas. Vi undersöker även vad det är som påverkar beslut och beslutsfattande i dessa organisationer. Tidigare forskning behandlar dels organisationsutveckling ur ett historiskt perspektiv och hur beslut kommer till, olika beslutsmodeller, hur beslut färdas och implementeras och kopplingen mellan beslut och ansvar. Det teoretiska perspektivet är Actor- Network Theory, ANT. Empirin har samlats in genom nio stycken kvalitativa intervjuer. Den har kodats och analyserats utifrån teorins begrepp aktör-nätverk, performativitet, handlingsnät och översättning. Beslut har analyserats som en symbol, vilken kan skapas och färdas inom organisationen med hjälp av olika aktörer. Studien visar på att begreppet beslut är starkt kopplat till ett agerande. Beslut som något performativt blir en översättningskedja som består av många detaljer som lättare beskrivs med ett sammanfattande beskrivande begrepp, beslut, för att kunna begripliggöra vad det är. Vi har även hittat faktorer i materialet som visar på hur beslut är kopplat till den decentraliserade strukturen samt att medarbetaren som individ blir viktig. Slutligen förs en diskussion av resultatet i förhållande till frågeställningar, tidigare forskning, teori och metod samt ger implikationer för vidare forskning inom ämnet.

Within the public sector great change efforts are currently made to meet future challenges. In the area of health care, change initiatives are implemented to enhance quality and efficiency. To this end, a lean change programme is being widely introduced in Sweden as well as internationally. The overriding aim of this study is to increase knowledge of what happens when change programmes, CP, such as lean are implemented in a healthcare organisation, HCO. Previous research has shown that the main obstacle to implementing CP in HCO:s is their complexity. However, the complexity has often been reduced, as different factors such as management, professions, organisation and control have been studied separately. To fully capture the complexity of the HCO the Actor Network Theory, ANT, was used in this study. In line with ANT, introducing lean can be described in terms of a translation process in which human and non-human actors are woven into a network. This approach allows for the incorporation of various factors in the study of a change process in a complex organisation. Drawing on ANT, this thesis explores how network constructions enable or impede change programmes. The approach is based on ethnographic monitoring of the implementation of lean in the Värmland county council public healthcare organisation. As a result of the holistic perspective, the study provides detailed descriptions of how complexity impacts on the implementation. It displays the relations enabling or impeding the implementation of CP and the methods actors use to establish and defend the relations. The contribution of the study is threefold. Empirically, the study monitors a HCO aiming to implement full-scale lean as philosophy, principle and tool. Methodologically, the study evaluates ANT as a methodological theory to study CP in a HCO. Finally, the domain-specific contribution of the study is its identification of the relations and methods that impact on lean deployment. / Kan förändringsprogram från den japanska bilindustrin lösa framtidens utmaningar inom hälso- och sjukvården? Ja, tycks svaret på frågan vara. Allt fler hälso- och sjukvårdsorganisationer väljer nämligen att införa och tillämpa lean i hopp om att öka kvalitet och effektivitet. I denna bok följer Stefan Hellman införandet av lean i ett av Sveriges landsting.   Tidigare forskning visar att förändringsprogram som lean kan resultera i positiva effekter när det införs i hälso- och sjukvården. Införandet är emellertid förknippat med problem. Hellman visar att det både finns anhängare och motståndare till lean. Han intervjuar och observerar anhängarna och motståndarna och identifierar därigenom hur de går tillväga för att underlätta respektive försvåra införandet av lean. Därigenom ger Hellman en inblick i hälso- och sjukvårdens komplexitet och visar vilka konsekvenser den ger när förändringsprogram införs i praktiken.

This thesis, based on a methodology borrowed from Science and Technologies Studies (STS), studies the implications of using energy modeling software for code compliance in the architectural design process. Specifically, the careful study of the development and use the of the software itself, including the assumptions and frameworks of its developers and users, is required to accurately examine the implications and practical effectiveness of using energy modeling to aid in reducing the environmental consequences of the built environment. I argue that the value in studying energy modeling software is not primarily to improve the scientific accuracy of the software. Rather, the value is to demonstrate how the assumptions used in the software’s calculation methodology can adversely influence the technological decisions made by building designers when using the software to demonstrate compliance with energy codes. To develop this hypothesis I have employed both historical and empirical methods. In my historical analysis, I find that the origins of modern building energy modeling software date back to the beginning of the air conditioning industry at the start of the 20th century. One consequence of this history is that assumptions built into the software measure the relative efficiency of building components under static and assumed average conditions, but not the dynamic rates of consumption caused by inhabitation. This, in-turn, prescribes the problem-at-hand of energy code compliance as primarily technical. However, as others have argued, dynamic social and circumstantial issues also influence energy consumption (Guy & Shove, 2000). Therefore as means to examine potential conflicts between the static and technical method of analysis employed by code compliance energy modeling software and the dynamic and circumstantial context in which buildings are designed, my empirical analysis is of a design process for a net-zero energy subdivision in Austin, Texas in which energy modeling was required and used extensively. The case study is designed to demonstrate how the problems-at-hand for each distinct group of stakeholders involved in the design process was varied and did not necessarily conform to the technical solution advocated by the energy modeling process. A primary conclusion of my analysis is that all mature technologies come to us with embedded assumptions that may subvert our intentions. A secondary conclusion is that the competing assumptions and problem definitions of building scientists and building designers tend to frustrate the goal of sustainable development. My hope in studying energy modeling, in relation to practice and code compliance, is to discover ways to better use the analytical power of energy modeling that is more directly responsive to the dynamic and contextual conditions of architectural production and real world resource consumption. / text

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