Matching Items (7)

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Commons governance for robust systems: irrigation systems study under a multi-method approach

Description

Sustainability depends in part on our capacity to resolve dilemmas of the commons in Coupled Infrastructure Systems (CIS). Thus, we need to know more about how to incentivize individuals to

Sustainability depends in part on our capacity to resolve dilemmas of the commons in Coupled Infrastructure Systems (CIS). Thus, we need to know more about how to incentivize individuals to take collective action to manage shared resources. Moreover, given that we will experience new and more extreme weather events due to climate change, we need to learn how to increase the robustness of CIS to those shocks. This dissertation studies irrigation systems to contribute to the development of an empirically based theory of commons governance for robust systems. I first studied the eight institutional design principles (DPs) for long enduring systems of shared resources that the Nobel Prize winner Elinor Ostrom proposed in 1990. I performed a critical literature review of 64 studies that looked at the institutional configuration of CIS, and based on my findings I propose some modifications of their definitions and application in research and policy making. I then studied how the revisited design principles, when analyzed conjointly with biophysical and ethnographic characteristics of CISs, perform to avoid over-appropriation, poverty and critical conflicts among users of an irrigation system. After carrying out a meta-analysis of 28 cases around the world, I found that particular combinations of those variables related to population size, countries corruption, the condition of water storage, monitoring of users behavior, and involving users in the decision making process for the commons governance, were sufficient to obtain the desired outcomes. The two last studies were based on the Peruvian Piura Basin, a CIS that has been exposed to environmental shocks for decades. I used secondary and primary data to carry out a longitudinal study using as guidance the robustness framework, and different hypothesis from prominent collapse theories to draw potential explanations. I then developed a dynamic model that shows how at the current situation it is more effective to invest in rules enforcement than in the improvement of the physical infrastructure (e.g. reservoir). Finally, I explored different strategies to increase the robustness of the system, through enabling collective action in the Basin.

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Created

Date Created
  • 2017

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Robustness of social-ecological system under global change: insights from community irrigation and forestry systems

Description

Social-ecological systems (SES) are replete with hard and soft human-made components (or infrastructures) that are consciously-designed to perform specific functions valued by humans. How these infrastructures mediate human-environment interactions is

Social-ecological systems (SES) are replete with hard and soft human-made components (or infrastructures) that are consciously-designed to perform specific functions valued by humans. How these infrastructures mediate human-environment interactions is thus a key determinant of many sustainability problems in present-day SES. This dissertation examines the question of how some of the designed aspects of physical and social infrastructures influence the robustness of SES under global change. Due to the fragility of rural livelihood systems, locally-managed common-pool resource systems that depend on infrastructure, such as irrigated agriculture and community forestry, are of particular importance to address this sustainability question. This dissertation presents three studies that explored the robustness of communal irrigation and forestry systems to economic or environmental shocks. The first study examined how the design of irrigation infrastructure affects the robustness of system performance to an economic shock. Using a stylized dynamic model of an irrigation system as a testing ground, this study shows that changes in infrastructure design can induce fundamental changes in qualitative system behavior (i.e., regime shifts) as well as altered robustness characteristics. The second study explored how connectedness among social units (a kind of social infrastructure) influenced the post-failure transformations of large-N forest commons under economic globalization. Using inferential statistics, the second study argues that some attributes of the social connectedness that helped system robustness in the past made the system more vulnerable to undesirable transformations in the current era. The third study explored the question of how to guide adaptive management of SES for more robustness under uncertainty. This study used an existing laboratory behavioral experiment in which human-subjects tackle a decision problem on collective management of an irrigation system under environmental uncertainty. The contents of group communication and the decisions of individuals were analyzed to understand how configurations of learning-by-doing and other adaptability-related conditions may be causally linked to robustness under environmental uncertainty. The results show that robust systems are characterized by two conditions: active learning-by-doing through outer-loop processes, i.e., frequent updating of shared assumptions or goals that underlie specific group strategies, and frequent monitoring and reflection of past outcomes.

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Date Created
  • 2015

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From policy instruments to action arenas: toward robust fisheries and adaptive fishing households in southwest Nova Scotia

Description

The coastal fishing community of Barrington, Southwest Nova Scotia (SWNS), has depended on the resilience of ocean ecosystems and resource-based economic activities for centuries. But while many coastal fisheries have

The coastal fishing community of Barrington, Southwest Nova Scotia (SWNS), has depended on the resilience of ocean ecosystems and resource-based economic activities for centuries. But while many coastal fisheries have developed unique ways to govern their resources, global environmental and economic change presents new challenges. In this study, I examine the multi-species fishery of Barrington. My objective was to understand what makes the fishery and its governance system robust to economic and ecological change, what makes fishing households vulnerable, and how household vulnerability and system level robustness interact. I addressed these these questions by focusing on action arenas, their contexts, interactions and outcomes. I used a combination of case comparisons, ethnography, surveys, quantitative and qualitative analysis to understand what influences action arenas in Barrington, Southwest Nova Scotia (SWNS). I found that robustness of the fishery at the system level depended on the strength of feedback between the operational level, where resource users interact with the resource, and the collective-choice level, where agents develop rules to influence fishing behavior. Weak feedback in Barrington has precipitated governance mismatches. At the household level, accounts from harvesters, buyers and experts suggested that decision-making arenas lacked procedural justice. Households preferred individual strategies to acquire access to and exploit fisheries resources. But the transferability of quota and licenses has created divisions between haves and have-nots. Those who have lost their traditional access to other species, such as cod, halibut, and haddock, have become highly dependent on lobster. Based on regressions and multi-criteria decision analysis, I found that new entrants in the lobster fishery needed to maintain high effort and catches to service their debts. But harvesters who did not enter the race for higher catches were most sensitive to low demand and low prices for lobster. This study demonstrates the importance of combining multiple methods and theoretical approaches to avoid tunnel vision in fisheries policy.

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Created

Date Created
  • 2014

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Diffusion in Networks: Source Localization, History Reconstruction and Real-Time Network Robustification

Description

Diffusion processes in networks can be used to model many real-world processes, such as the propagation of a rumor on social networks and cascading failures on power networks. Analysis of

Diffusion processes in networks can be used to model many real-world processes, such as the propagation of a rumor on social networks and cascading failures on power networks. Analysis of diffusion processes in networks can help us answer important questions such as the role and the importance of each node in the network for spreading the diffusion and how to top or contain a cascading failure in the network. This dissertation consists of three parts.

In the first part, we study the problem of locating multiple diffusion sources in networks under the Susceptible-Infected-Recovered (SIR) model. Given a complete snapshot of the network, we developed a sample-path-based algorithm, named clustering and localization, and proved that for regular trees, the estimators produced by the proposed algorithm are within a constant distance from the real sources with a high probability. Then, we considered the case in which only a partial snapshot is observed and proposed a new algorithm, named Optimal-Jordan-Cover (OJC). The algorithm first extracts a subgraph using a candidate selection algorithm that selects source candidates based on the number of observed infected nodes in their neighborhoods. Then, in the extracted subgraph, OJC finds a set of nodes that "cover" all observed infected nodes with the minimum radius. The set of nodes is called the Jordan cover, and is regarded as the set of diffusion sources. We proved that OJC can locate all sources with probability one asymptotically with partial observations in the Erdos-Renyi (ER) random graph. Multiple experiments on different networks were done, which show our algorithms outperform others.

In the second part, we tackle the problem of reconstructing the diffusion history from partial observations. We formulated the diffusion history reconstruction problem as a maximum a posteriori (MAP) problem and proved the problem is NP hard. Then we proposed a step-by- step reconstruction algorithm, which can always produce a diffusion history that is consistent with the partial observations. Our experimental results based on synthetic and real networks show that the algorithm significantly outperforms some existing methods.

In the third part, we consider the problem of improving the robustness of an interdependent network by rewiring a small number of links during a cascading attack. We formulated the problem as a Markov decision process (MDP) problem. While the problem is NP-hard, we developed an effective and efficient algorithm, RealWire, to robustify the network and to mitigate the damage during the attack. Extensive experimental results show that our algorithm outperforms other algorithms on most of the robustness metrics.

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Created

Date Created
  • 2018

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Dynamic programming algorithm for computing temporal logic robustness

Description

In this thesis we deal with the problem of temporal logic robustness estimation. We present a dynamic programming algorithm for the robust estimation problem of Metric Temporal Logic (MTL) formulas

In this thesis we deal with the problem of temporal logic robustness estimation. We present a dynamic programming algorithm for the robust estimation problem of Metric Temporal Logic (MTL) formulas regarding a finite trace of time stated sequence. This algorithm not only tests if the MTL specification is satisfied by the given input which is a finite system trajectory, but also quantifies to what extend does the sequence satisfies or violates the MTL specification. The implementation of the algorithm is the DP-TALIRO toolbox for MATLAB. Currently it is used as the temporal logic robust computing engine of S-TALIRO which is a tool for MATLAB searching for trajectories of minimal robustness in Simulink/ Stateflow. DP-TALIRO is expected to have near linear running time and constant memory requirement depending on the structure of the MTL formula. DP-TALIRO toolbox also integrates new features not supported in its ancestor FW-TALIRO such as parameter replacement, most related iteration and most related predicate. A derivative of DP-TALIRO which is DP-T-TALIRO is also addressed in this thesis which applies dynamic programming algorithm for time robustness computation. We test the running time of DP-TALIRO and compare it with FW-TALIRO. Finally, we present an application where DP-TALIRO is used as the robustness computation core of S-TALIRO for a parameter estimation problem.

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Agent

Created

Date Created
  • 2013

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Robustness of Latent variable interaction methods to nonnormal exogenous indicators

Description

For this thesis a Monte Carlo simulation was conducted to investigate the robustness of three latent interaction modeling approaches (constrained product indicator, generalized appended product indicator (GAPI), and latent moderated

For this thesis a Monte Carlo simulation was conducted to investigate the robustness of three latent interaction modeling approaches (constrained product indicator, generalized appended product indicator (GAPI), and latent moderated structural equations (LMS)) under high degrees of nonnormality of the exogenous indicators, which have not been investigated in previous literature. Results showed that the constrained product indicator and LMS approaches yielded biased estimates of the interaction effect when the exogenous indicators were highly nonnormal. When the violation of nonnormality was not severe (symmetric with excess kurtosis < 1), the LMS approach with ML estimation yielded the most precise latent interaction effect estimates. The LMS approach with ML estimation also had the highest statistical power among the three approaches, given that the actual Type-I error rates of the Wald and likelihood ratio test of interaction effect were acceptable. In highly nonnormal conditions, only the GAPI approach with ML estimation yielded unbiased latent interaction effect estimates, with an acceptable actual Type-I error rate of both the Wald test and likelihood ratio test of interaction effect. No support for the use of the Satorra-Bentler or Yuan-Bentler ML corrections was found across all three methods.

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Agent

Created

Date Created
  • 2010

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The semiotic nature of power in social-ecological systems

Description

Anderies (2015); Anderies et al. (2016), informed by Ostrom (2005), aim to employ robust

feedback control models of social-ecological systems (SESs), to inform policy and the

design of institutions guiding resilient resource

Anderies (2015); Anderies et al. (2016), informed by Ostrom (2005), aim to employ robust

feedback control models of social-ecological systems (SESs), to inform policy and the

design of institutions guiding resilient resource use. Cote and Nightingale (2012) note that

the main assumptions of resilience research downplay culture and social power. Addressing

the epistemic gap between positivism and interpretation (Rosenberg 2016), this dissertation

argues that power and culture indeed are of primary interest in SES research.

Human use of symbols is seen as an evolved semiotic capacity. First, representation is

argued to arise as matter achieves semiotic closure (Pattee 1969; Rocha 2001) at the onset

of natural selection. Guided by models by Kauffman (1993), the evolution of a symbolic

code in genes is examined, and thereon the origin of representations other than genetic

in evolutionary transitions (Maynard Smith and Szathmáry 1995; Beach 2003). Human

symbolic interaction is proposed as one that can support its own evolutionary dynamics.

The model offered for wider dynamics in society are “flywheels,” mutually reinforcing

networks of relations. They arise as interactions in a domain of social activity intensify, e.g.

due to interplay of infrastructures, mediating built, social, and ecological affordances (An-

deries et al. 2016). Flywheels manifest as entities facilitated by the simplified interactions

(e.g. organizations) and as cycles maintaining the infrastructures (e.g. supply chains). They

manifest internal specialization as well as distributed intention, and so can favor certain

groups’ interests, and reinforce cultural blind spots to social exclusion (Mills 2007).

The perspective is applied to research of resilience in SESs, considering flywheels a

semiotic extension of feedback control. Closer attention to representations of potentially

excluded groups is justified on epistemic in addition to ethical grounds, as patterns in cul-

tural text and social relations reflect the functioning of wider social processes. Participatory

methods are suggested to aid in building capacity for institutional learning.

Contributors

Agent

Created

Date Created
  • 2017