Matching Items (3)
Description
Motor-respiratory coordination is the synchronization of movement and breathing during exercise. The relation between movement and breathing can be described using relative phase, a measure of the location in the movement cycle relative to the location in the breathing cycle. Stability in that relative phase relation has been identified as important for aerobic efficiency. However, performance can be overly attracted to stable relative phases, preventing the performance or learning of more complex patterns. Little research exists on relative phase dynamics in motor-respiratory coordination, although those observations underscore the importance of learning more. In contrast, there is an extensive literature on relative phase dynamics in interlimb coordination. The accuracy and stability of different relative phases, transitions between patterns, and asymmetries between components are well understood. Theoretically, motor-respiratory and interlimb coordination may share dynamical properties that operate in their different physiological substrates. An existing model of relative phase dynamics in interlimb coordination, the Haken, Kelso, Bunz model, was used to gain an understanding of relative phase dynamics in the less-researched motor-respiratory coordination. Experiments 1 and 2 were designed to examine the interaction of frequency asymmetries between movement and breathing with relative phase and frequency, respectively. In Experiment 3, relative phase stability and transitions in motor-respiratory coordination were explored. Perceptual constraints on differences in stability were investigated in Experiment 4. Across experiments, contributions relevant to questions of coordinative variability were made using a dynamical method called cross recurrence quantification analysis. Results showed much consistency with predictions from an asymmetric extension of the Haken, Kelso, Bunz model and theoretical interpretation in the interlimb coordination literature, including phase wandering, intermittency, and an interdependence of perception and action. There were, however, notable exceptions that indicated stability can decrease with more natural frequency asymmetries and the connection of cross recurrence measures to categories of variability needs further clarification. The complex relative phase dynamics displayed in this study suggest that movement and breathing are softly-assembled by functional constraints and indicate that motor-respiratory coordination is a self-organized system.
ContributorsHessler, Eric Edward (Author) / Amazeen, Polemnia G (Thesis advisor) / Amazeen, Eric L (Committee member) / Glenberg, Arthur M. (Committee member) / Gray, Rob (Committee member) / Arizona State University (Publisher)
Created2010
Description
Management of emergency or crisis events relies on the collaborative efforts of a wide range of organizations. How to coordinate their efforts becomes a pressing challenge for public administration. This three-essay dissertation informs our understanding of public agencies’ inter-organizational coordination in preparation for and response to emergencies and disasters. The first essay provides an overview of emergency coordination research by systematically reviewing the fragmented inter-disciplinary literature on the topic for the past two decades. Through the analyses of 64 articles, the essay maps major theoretical traditions of emergency coordination research and identifies the need for further theoretical explorations. The syntheses of findings from the literature provide empirical strategies for improving response coordination effectiveness. The review reveals that current research predominantly focuses on response coordination with little understanding of coordination at other emergency management phases. Building upon the first essay, the second essay examines coordination in the preparedness phase. By introducing the configurational approach to emergency management research, the study explores which configurations of organizational attributes – and environmental characteristics – lead to active emergency preparedness coordination. A configurational model for preparedness coordination is proposed along with three propositions. The study conducts a large-N fuzzy-set qualitative comparative analysis (QCA) to analyze U.S. public transit agencies’ inter-organizational coordination in preparation for extreme weather events. Findings demonstrate the value of configurational thinking and suggest the importance of managerial commitment. The third essay extends the current inquiry on response coordination by reorienting the focus to the role of human agency. Drawing from institutional logic theory, the study identifies the systems of cultural elements (i.e., institutional logic) that affect inter-organizational response coordination actions. Influential managerial practices are also specified. The empirical context of this study is the local government's response to the Covid-19 pandemic in Arizona. Findings demonstrate that coordination actions are under the influence of professional and community logics. Empirical evidence also corroborates the importance of management practices for coordination. Taken together, the dissertation contributes to emergency management research by engaging novel theoretical perspectives and diverse methodological approaches. It provides actionable strategies for public managers to improve coordination effectiveness.
ContributorsXiang, Tianyi (Author) / Gerber, Brian (Thesis advisor) / Howitt, Arnold (Committee member) / Mossberger, Karen (Committee member) / Welch, Eric (Committee member) / Arizona State University (Publisher)
Created2022
Description
Agricultural supply chains are complex systems which pose significant challenges beyond those of traditional supply chains. These challenges include: long lead times, stochastic yields, short shelf lives and a highly distributed supply base. This complexity makes coordination critical to prevent food waste and other inefficiencies. Yet, supply chains of fresh produce suffer from high levels of food waste; moreover, their high fragmentation places a great economic burden on small and medium sized farms.
This research develops planning tools tailored to the production/consolidation level in the supply chain, taking the perspective of an agricultural cooperative—a business model which presents unique coordination challenges. These institutions are prone to internal conflict brought about by strategic behavior, internal competition and the distributed nature of production information, which members keep private.
A mechanism is designed to coordinate agricultural production in a distributed manner with asymmetrically distributed information. Coordination is achieved by varying the prices of goods in an auction like format and allowing participants to choose their supply quantities; the auction terminates when production commitments match desired supply.
In order to prevent participants from misrepresenting their information, strategic bidding is formulated from the farmer’s perspective as an optimization problem; thereafter, optimal bidding strategies are formulated to refine the structure of the coordination mechanism in order to minimize the negative impact of strategic bidding. The coordination mechanism is shown to be robust against strategic behavior and to provide solutions with a small optimality gap. Additional information and managerial insights are obtained from bidding data collected throughout the mechanism. It is shown that, through hierarchical clustering, farmers can be effectively classified according to their cost structures.
Finally, considerations of stochastic yields as they pertain to coordination are addressed. Here, the farmer’s decision of how much to plant in order to meet contracted supply is modeled as a newsvendor with stochastic yields; furthermore, options contracts are made available to the farmer as tools for enhancing coordination. It is shown that the use of option contracts reduces the gap between expected harvest quantities and the contracted supply, thus facilitating coordination.
This research develops planning tools tailored to the production/consolidation level in the supply chain, taking the perspective of an agricultural cooperative—a business model which presents unique coordination challenges. These institutions are prone to internal conflict brought about by strategic behavior, internal competition and the distributed nature of production information, which members keep private.
A mechanism is designed to coordinate agricultural production in a distributed manner with asymmetrically distributed information. Coordination is achieved by varying the prices of goods in an auction like format and allowing participants to choose their supply quantities; the auction terminates when production commitments match desired supply.
In order to prevent participants from misrepresenting their information, strategic bidding is formulated from the farmer’s perspective as an optimization problem; thereafter, optimal bidding strategies are formulated to refine the structure of the coordination mechanism in order to minimize the negative impact of strategic bidding. The coordination mechanism is shown to be robust against strategic behavior and to provide solutions with a small optimality gap. Additional information and managerial insights are obtained from bidding data collected throughout the mechanism. It is shown that, through hierarchical clustering, farmers can be effectively classified according to their cost structures.
Finally, considerations of stochastic yields as they pertain to coordination are addressed. Here, the farmer’s decision of how much to plant in order to meet contracted supply is modeled as a newsvendor with stochastic yields; furthermore, options contracts are made available to the farmer as tools for enhancing coordination. It is shown that the use of option contracts reduces the gap between expected harvest quantities and the contracted supply, thus facilitating coordination.
ContributorsMason De Rada, Andrew Nicholas (Author) / Villalobos, Jesus R (Thesis advisor) / Griffin, Paul (Committee member) / Kempf, Karl (Committee member) / Wu, Teresa (Committee member) / Arizona State University (Publisher)
Created2015