Knowledge discovery in multi-relational graphs

Ante el reducido abanico de metodologías para llevar a cabo tareas de aprendizaje automático relacional, el objetivo principal de esta tesis es realizar un análisis de los métodos existentes, modificando u optimizando en la medida de lo posible algunos de ellos, y aportar nuevos métodos que proporcionen nuevas vías para abordar esta difícil tarea. Para ello, y sin nombrar objetivos relacionados con revisiones bibliográficas ni comparativas entre modelos e implementaciones, se plantean una serie de objetivos concretos a ser cubiertos: 1. Definir estructuras flexibles y potentes que permitan modelar fenómenos en base a los elementos que los componen y a las relaciones establecidas entre éstos. Dichas estructuras deben poder expresar de manera natural propiedades complejas (valores continuos o categóricos, vectores, matrices, diccionarios, grafos,...) de los elementos, así como relaciones heterogéneas entre éstos que a su vez puedan poseer el mismo nivel de propiedades complejas. Además, dichas estructuras deben permitir modelar fenómenos en los que las relaciones entre los elementos no siempre se dan de forma binaria (intervienen únicamente dos elementos), sino que puedan intervenir un número cualquiera de ellos. 2. Definir herramientas para construir, manipular y medir dichas estructuras. Por muy potente y flexible que sea una estructura, será de poca utilidad si no se poseen las herramientas adecuadas para manipularla y estudiarla. Estas herramientas deben ser eficientes en su implementación y cubrir labores de construcción y consulta. 3. Desarrollar nuevos algoritmos de aprendizaje automático relacional de caja negra. En aquellas tareas en las que nuestro objetivo no es obtener modelos explicativos, podremos permitirnos utilizar modelos de caja negra, sacrificando la interpretabilidad a favor de una mayor eficiencia computacional. 4. Desarrollar nuevos algoritmos de aprendizaje automático relacional de caja blanca. Cuando estamos interesados en una explicación acerca del funcionamiento de los sistemas que se analizan, buscaremos modelos de aprendizaje automático de caja blanca. 5. Mejorar las herramientas de consulta, análisis y reparación para bases de datos. Algunas de las consultas a larga distancia en bases de datos presentan un coste computacional demasiado alto, lo que impide realizar análisis adecuados en algunos sistemas de información. Además, las bases de datos en grafo carecen de métodos que permitan normalizar o reparar los datos de manera automática o bajo la supervisión de un humano. Es interesante aproximarse al desarrollo de herramientas que lleven a cabo este tipo de tareas aumentando la eficiencia y ofreciendo una nueva capa de consulta y normalización que permita curar los datos para un almacenamiento y una recuperación más óptimos. Todos los objetivos marcados son desarrollados sobre una base formal sólida, basada en Teoría de la Información, Teoría del Aprendizaje, Teoría de Redes Neuronales Artificiales y Teoría de Grafos. Esta base permite que los resultados obtenidos sean suficientemente formales como para que los aportes que se realicen puedan ser fácilmente evaluados. Además, los modelos abstractos desarrollados son fácilmente implementables sobre máquinas reales para poder verificar experimentalmente su funcionamiento y poder ofrecer a la comunidad científica soluciones útiles en un corto espacio de tiempo

Provenance Management for Collaborative Data Science Workflows

Collaborative data science activities are becoming pervasive in a variety of communities, and are often conducted in teams, with people of different expertise performing back-and-forth modeling and analysis on time-evolving datasets. Current data science systems mainly focus on specific steps in the process such as training machine learning models, scaling to large data volumes, or serving the data or the models, while the issues of end-to-end data science lifecycle management are largely ignored. Such issues include, for example, tracking provenance and derivation history of models, identifying data processing pipelines and keeping track of their evolution, analyzing unexpected behaviors and monitoring the project health, and providing the ability to reason about specific analysis results. We address these challenges by ingesting, managing, and analyzing rich provenance information generated during data science projects, and using it to enable users to easily publish, share, and discover data analytics projects. We first describe the design of our unified provenance and metadata management system, called ProvDB. We adopt a schema-later approach and use a flexible graph-based provenance representation model that combines the core concepts in version control and provenance management. We describe several ingestion mechanisms for this provenance model and show how heterogeneous data analysis environments can be served with natural extensions to this framework. We also describe a set of novel features of the system including graph queries for retrospective provenance, fileviews for data transformations, introspective queries for debugging, and continuous monitoring queries for anomaly detection. We then illustrate how to support deep learning modeling lifecycle via the extensibility mechanism in ProvDB. We describe techniques to compactly store and efficiently query the rich set of data artifacts generated during deep learning modeling lifecycle. We also describe a high-level domain specific language that helps raise the abstraction level during model exploration and enumeration and accelerate the modeling process. Lastly, we propose graph query operators and develop efficient evaluation techniques to address the verbose and evolving nature of such provenance graphs. First, we introduce a graph segmentation operator, which queries the provenance of a collection of user-given vertices (e.g., versioned files, author names) via flexible boundary criteria. Second, we propose a graph summarization operator to aggregate the results of multiple segmentation operations, and allow multi-resolution interaction with the aggregation result to understand similar and abnormal behaviors in those segments

Smart Urban Water Networks

This book presents the paper form of the Special Issue (SI) on Smart Urban Water Networks. The number and topics of the papers in the SI confirm the growing interest of operators and researchers for the new paradigm of smart networks, as part of the more general smart city. The SI showed that digital information and communication technology (ICT), with the implementation of smart meters and other digital devices, can significantly improve the modelling and the management of urban water networks, contributing to a radical transformation of the traditional paradigm of water utilities. The paper collection in this SI includes different crucial topics such as the reliability, resilience, and performance of water networks, innovative demand management, and the novel challenge of real-time control and operation, along with their implications for cyber-security. The SI collected fourteen papers that provide a wide perspective of solutions, trends, and challenges in the contest of smart urban water networks. Some solutions have already been implemented in pilot sites (i.e., for water network partitioning, cyber-security, and water demand disaggregation and forecasting), while further investigations are required for other methods, e.g., the data-driven approaches for real time control. In all cases, a new deal between academia, industry, and governments must be embraced to start the new era of smart urban water systems

METROPOLITAN ENCHANTMENT AND DISENCHANTMENT. METROPOLITAN ANTHROPOLOGY FOR THE CONTEMPORARY LIVING MAP CONSTRUCTION

We can no longer interpret the contemporary metropolis as we did in the last century. The thought of civil economy regarding the contemporary Metropolis conflicts more or less radically with the merely acquisitive dimension of the behaviour of its citizens. What is needed is therefore a new capacity for imagining the economic-productive future of the city: hybrid social enterprises, economically sustainable, structured and capable of using technologies, could be a solution for producing value and distributing it fairly and inclusively. Metropolitan Urbanity is another issue to establish. Metropolis needs new spaces where inclusion can occur, and where a repository of the imagery can be recreated. What is the ontology behind the technique of metropolitan planning and management, its vision and its symbols? Competitiveness, speed, and meritocracy are political words, not technical ones. Metropolitan Urbanity is the characteristic of a polis that expresses itself in its public places. Today, however, public places are private ones that are destined for public use. The Common Good has always had a space of representation in the city, which was the public space. Today, the Green-Grey Infrastructure is the metropolitan city's monument that communicates a value for future generations and must therefore be recognised and imagined; it is the production of the metropolitan symbolic imagery, the new magic of the city

Improvements to the functionality of the mycanesim® irrigation scheduling advice system for sugarcane.

Master of Science in Bioresources Engineering. University of KwaZulu-Natal, Pietermaritzburg 2016.MyCanesim® is a web-based crop simulation system that can be used for irrigation scheduling and yield estimation. Two shortcomings of the system identified were that 1) advised irrigation amounts could exceed seasonal water limitations imposed on farmers and 2) simulations are only accurate if farmers follow the recommended irrigation actions and if simulated and actual available soil water content are similar. These can be addressed by incorporating algorithms for optimal scheduling of limited water, and by making use of soil water content measurements in model simulations. The objectives of this study were to 1) evaluate the performance of different optimization algorithms that schedule limited water and 2) determine the accuracy of irrigation scheduling advice and cane yield estimates with and without adjustment of simulations with soil water content records. Four irrigation scheduling algorithms were tested against a baseline algorithm, using 960 hypothetical scenarios consisting of different water supply, climate and cropping situations. These were: (a) Crop stage, which accounts for the yield sensitivity to water deficit as it varies with growth stage; (b) Stress level, which evaluates different soil water depletion levels for determining irrigation dates; (c) Prorata, which reduces irrigation throughout the growing season in proportion to the seasonal allocation shortfall; and (d) Water satisfaction, which iteratively schedules irrigation events on the day with the largest water demand. Algorithms increased simulated yields over the baseline by between 4.7 and 8.6 t/ha on average and operated at computational running times of between 1 and 40 s. The stress level algorithm was recommended for inclusion into MyCanesim®, since it had both a high yield improvement (8.5 t/ha) and quick operational time (2.5 s). Soil water measurements from capacitance probes for thirteen fields in Mpumalanga were integrated through an automated process into the MyCanesim® system. The improvements in the accuracy of irrigation scheduling advice and yield estimates by the integrated system were assessed retrospectively. The integrated system resulted in more accurate irrigation scheduling advice (by 2 days) than weather-based scheduling alone. These two improvements to MyCanesim® should allow sugarcane farmers to achieve higher irrigated water use efficiency and yields because of more accurate irrigation scheduling advice and yield estimates for full and restricted irrigation water supply

Migrant Ecologies

<p>Migrant Ecologies: Environmental Histories of the Pacific World is the first volume explicitly dedicated to the environmental history of Earth’s largest ocean. Covering nearly one-third of the planet, the Pacific Ocean is remarkable for its diverse human and non-human inhabitants, their astounding long-distance migrations over time, and their profound influences on other parts of the world. This book creates an understanding of the past, present, and futures of the lands, seas, peoples, practices, microbes, animals, plants, and other natural forces that shape the Pacific. It effectively argues for the existence of an interconnected Pacific World environmental history, as well as for the Pacific Ocean as a necessary framework for understanding that history.<br><br>The fifteen chapters in this comprehensive collection, written by leading experts from across the globe, span a vast array of topics, from disease ecology and coffee cultivation to nuclear testing and whaling practices. They explore regions stretching from the Tuamotu Archipelago in the south Pacific to the Kamchatka Peninsula in the far north, resisting the depiction of the Pacific as isolated and uninhabited. What unites these diverse contributions is a concern for how the people, places, and non-human beings of the Pacific World have been shaped by, and have in turn modified, their oceanic realm. Building on a recent renaissance in Pacific history, these chapters make a powerful argument for the importance of the Pacific World as a coherent unit of analysis and a valuable lens through which to examine past, ongoing, and emerging environmental issues. By showcasing surprising and innovative perspectives on the environmental histories of the peoples and ecosystems in and around the Pacific Ocean, this work adds to current conversations and debates about the Pacific World and offers myriad opportunities for further discussions, both inside and outside of the classroom.</p&gt

Migrant Ecologies

<p>Migrant Ecologies: Environmental Histories of the Pacific World is the first volume explicitly dedicated to the environmental history of Earth’s largest ocean. Covering nearly one-third of the planet, the Pacific Ocean is remarkable for its diverse human and non-human inhabitants, their astounding long-distance migrations over time, and their profound influences on other parts of the world. This book creates an understanding of the past, present, and futures of the lands, seas, peoples, practices, microbes, animals, plants, and other natural forces that shape the Pacific. It effectively argues for the existence of an interconnected Pacific World environmental history, as well as for the Pacific Ocean as a necessary framework for understanding that history.<br><br>The fifteen chapters in this comprehensive collection, written by leading experts from across the globe, span a vast array of topics, from disease ecology and coffee cultivation to nuclear testing and whaling practices. They explore regions stretching from the Tuamotu Archipelago in the south Pacific to the Kamchatka Peninsula in the far north, resisting the depiction of the Pacific as isolated and uninhabited. What unites these diverse contributions is a concern for how the people, places, and non-human beings of the Pacific World have been shaped by, and have in turn modified, their oceanic realm. Building on a recent renaissance in Pacific history, these chapters make a powerful argument for the importance of the Pacific World as a coherent unit of analysis and a valuable lens through which to examine past, ongoing, and emerging environmental issues. By showcasing surprising and innovative perspectives on the environmental histories of the peoples and ecosystems in and around the Pacific Ocean, this work adds to current conversations and debates about the Pacific World and offers myriad opportunities for further discussions, both inside and outside of the classroom.</p&gt

Great river wood dynamics in northern Canada

2016 Summer.Includes bibliographical references.Downed wood is a resource easily utilized by plants and animals from the forests to the sea and is essential for many ecosystems. The diverse benefits that wood brings to streams and riparian corridors are well documented by river scientists and wood re-introduction is commonly used as a river restoration tool. However, much of the existing work investigates the short-term impact of wood rather than its variability through time and legacy on the landscape. In this dissertation, I use the Slave River (water discharge=2-7 x103 m3 s −1 , channel widths=300-2000 m, drainage area=6x105 km2 ), and its receiving sedimentary basin, the Great Slave Lake (surface area=273 km2 , depths 20-600 m, volume 1000-2000 km3 ), in northern Canada to better understand wood transport dynamics of a major river basin across varied timescales from minutes to centuries and the influence of driftwood on shoreline landscape evolution. The four primary contributions of this work are: a comprehensive literature review and synthesis of wood transport in rivers worldwide (Chapter 1), new methods for monitoring and quantifying wood flux with timelapse cameras (Chapter 2), description of processes among driftwood, sediment, and vegetation that result in shoreline features that I have coined "driftcretions" (Chapter 3), and expansion of wood transport research into multiple timescales with a focus on how flow history impacts magnitude of wood flux (Chapter 4). In Chapter 1, I: qualitatively summarize existing transport research around flow, wood and reach characteristics, quantitatively consolidate and analyze wood mobility field data in relation to increasing channel size, identify disconnects between driving processes and how mobility is measured, and constrain and conceptualize thresholds between wood dynamic ii regimes. In Chapter 2, I introduce a cheap, useful and fast way to monitor and estimate wood flux with timelapse photography through the use of the metric p, the probability of seeing wood within a timeframe, and I provide statistical methods to estimate appropriate sampling intervals to minimize bias and variance. In Chapter 3, I describe processes and rates by which pulsed driftwood export are delivered and accreted to shorelines and I discuss how these processes influence rates of carbon sequestration, sediment storage and habitat formation. In Chapter 4, I use a variety of methods centered around repeat photography and anecdotes to assess temporal variability of pulsed driftwood flux through the Slave River in the past century. Findings in this dissertation provide useful information for understanding pulsed wood flux, shoreline dynamics and landforms in marine and terrestrial water bodies before widespread historical deforestation, damming of rivers, and wood removal along major waterways. I not only synthesize and link existing work on wood mobilization, transport and deposition to an intriguing case study, but challenge existing wood transport premises, provide new conceptual models describing processes of wood transport through drainage networks, and present new approaches and methods for quantifying and analyzing the variability in wood flux and influence of wood deposits on landforms. My descriptions of wood transport and shoreline processes prior to development of river corridors will be an invaluable resource to groups who seek to identify environmental impacts of dams and to scientists who are investigating the impact that past and future development of river corridors has had or will have on ecosystems