Transportation Environments: The Politics, Ecology, and Infrastructure of the Panama Canal

Many of us think of the Panama Canal as an excavated channel between the Atlantic Ocean and Pacific Ocean that was finished nearly a century ago. Open nearly any historical work on the canal and you will read about a monumental engineering project completed in 1914 by virtue of political will, technological innovation, and migrant labor. The protagonists of these accounts - typically politicians, engineers, and thousands of laborers - overcame significant obstacles and united the oceans, fulfilling a colonial dream of interoceanic transit and cementing a modern vision of global connection. I argue that this narrative, which might be called the big ditch story, is not inaccurate, but is too restrictive. This is to say that a focus on historical excavation elides the ongoing political, ecological, and infrastructural work across the region around the waterway that makes interoceanic transportation possible. My dissertation, which draws on ethnographic fieldwork and archival research conducted in Panama and the United States, reveals a constantly changing canal in which concrete and steel forms are bound up with water, soil, forests, and social life. This built environment is highly politicized, given shape through the diverse, sometimes oppositional projects that have been pursued by United States and Panamanian state institutions, capitalists, scientists, and people whose livelihoods depend directly on the land. The four main body chapters of the dissertation each examine a different aspect of changing political, ecological, and infrastructural relationships around the Panama Canal. Each chapter focuses on an object (water, bananas, concrete, and forests) and a related theme (control/excess, governance/margins, politics/mobility, nature/infrastructure). Through these case studies, I develop an analytical framework that I call the political ecology of infrastructureDoctor of Philosoph

Deep reinforcement learning for multi-domain dialogue systems

Standard deep reinforcement learning methods such as Deep Q-Networks (DQN) for multiple tasks (domains) face scalability problems. We propose a method for multi-domain dialogue policy learning---termed NDQN, and apply it to an information-seeking spoken dialogue system in the domains of restaurants and hotels. Experimental results comparing DQN (baseline) versus NDQN (proposed) using simulations report that our proposed method exhibits better scalability and is promising for optimising the behaviour of multi-domain dialogue systems

Scaling up deep reinforcement learning for multi-domain dialogue systems

Standard deep reinforcement learning methods such as Deep Q-Networks (DQN) for multiple tasks (domains) face scalability problems due to large search spaces. This paper proposes a three-stage method for multi-domain dialogue policy learning—termed NDQN, and applies it to an information-seeking spoken dialogue system in the domains of restaurants and hotels. In this method, the first stage does multi-policy learning via a network of DQN agents; the second makes use of compact state representations by compressing raw inputs; and the third stage applies a pre-training phase for bootstraping the behaviour of agents in the network. Experimental results comparing DQN (baseline) versus NDQN (proposed) using simulations report that the proposed method exhibits better scalability and is promising for optimising the behaviour of multi-domain dialogue systems. An additional evaluation reports that the NDQN agents outperformed a K-Nearest Neighbour baseline in task success and dialogue length, yielding more efficient and successful dialogues

Poverty and maternal mortality in Nigeria: towards a more viable ethics of modern medical practice

Poverty is often identified as a major barrier to human development. It is also a powerful brake on accelerated progress toward the Millennium Development Goals. Poverty is also a major cause of maternal mortality, as it prevents many women from getting proper and adequate medical attention due to their inability to afford good antenatal care. This Paper thus examines poverty as a threat to human existence, particularly women's health. It highlights the causes of maternal deaths in Nigeria by questioning the practice of medicine in this country, which falls short of the ethical principle of showing care

An Infrastructural Event: Making Sense of Panama’s Drought

Droughts are often characterised as meteorological events: periodic precipitation deficits associated with atmospheric disruption. However, the droughts that concern our societies are typically socioeconomic events: instances in which water demand approaches or exceeds a supply diminished due to low precipitation. This article analyses a 2015-16 drought in Panama, typically among the world’s rainiest countries, to argue that some droughts might be usefully conceptualised as infrastructural events. This analytic complements research on climatic and socioeconomic dynamics by opening up lines of inquiry that might reframe drought events. When, for example, does a drought begin and end? Where do droughts come from? Who and what are (in)visible in drought explanations and responses? The article is organised around three key dimensions of the infrastructural event, each responding to one of the questions above. The first, momentum, makes the case for a deeper temporal understanding of drought that attends to the inertia of water-intensive sociotechnical systems. The second, interconnection, examines how linkages between these systems and regional-to-global infrastructure networks can amplify situated water demands. The third, visibility, explores the mechanisms through which infrastructure frames understandings of and responses to drought, including the normalisation of water distribution politics

Trees and trade-offs : perceptions of eucalyptus and native trees in Ecuadorian highland communities

In the northern Ecuadorian Andes, the land area covered in native forests has diminished in recent decades while that covered in forest plantations - planted primarily with Eucalyptus species - has increased rapidly. Between October 2003 and March 2004, the author conducted forty semi-structured interviews with inhabitants of two indigenous Quichua communities near Cotacachi, Ecuador, seeking perceptions of eucalyptus and native trees. These tree types are thought to have distinct ecological and economic costs and benefits and are thus valued for different reasons in the study communities. While many community members recognize the potential ecological dangers of monocultures of Eucalyptus species, they appreciate the trees\u27 accessibility, utility, and monetary value. Native trees, by contrast, are considered to be very important ecologically and to provide economic benefits distinct from those of plantation species, but are also seen as less accessible due to diminished quantities

Trees and trade-offs : perceptions of eucalyptus and native trees in Ecuadorian highland communities

In the northern Ecuadorian Andes, the land area covered in native forests has diminished in recent decades while that covered in forest plantations - planted primarily with Eucalyptus species - has increased rapidly. Between October 2003 and March 2004, the author conducted forty semi-structured interviews with inhabitants of two indigenous Quichua communities near Cotacachi, Ecuador, seeking perceptions of eucalyptus and native trees. These tree types are thought to have distinct ecological and economic costs and benefits and are thus valued for different reasons in the study communities. While many community members recognize the potential ecological dangers of monocultures of Eucalyptus species, they appreciate the trees\u27 accessibility, utility, and monetary value. Native trees, by contrast, are considered to be very important ecologically and to provide economic benefits distinct from those of plantation species, but are also seen as less accessible due to diminished quantities