26 research outputs found

    Machine learning approaches for considering decentralized EVB pre-processing facilities with respect to end-use sectors and a potential second-use location

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    Lithium-Ion Batteries (LIBs) at End-of-Life (EoL) pose several safety risks, as LIBs have the potential to self-ignite during transportation, release toxic compounds during incineration, and can leach contaminants into landfills. To reduce these safety risks in US, LIBs are labeled Class 9 hazardous materials under the Code of Federal Regulations. This causes LIBs to be subject to numerous policies, including the requirement of certified personnel and companies to pack and ship the items, and regulatory processing with government agencies involved in transport. Efforts to improve LIB recycling focus on reducing costs to make recycling economically lucrative. Hence, there is a significant emphasis on improving recycling processes; however, transport cost alone has been identified to be on average 41% of the total cost of LIB recycling. This thesis aims to provide a methodology for choosing a Spatially Constrained Multivariate Clustering Analysis (SCMCA) heuristic which could be implemented in a variety of applications. A case study is analyzed which investigates network optimization for potential decentralized pre-processing facility locations of Electric Vehicle Batteries (EVBs) in California. The decentralized facilities aim to minimize the transportation distance and costs of shipping intact EVBs between end-use sectors, the facilities, and potential seconduse locations. The methodology consists of a clustering analysis comparison of unsupervised SCMCA Machine Learning heuristics followed by location analyses of potential pre-processing facilities. The freight capacity of the solutions under different transportation scenarios is utilized as the primary criteria to determine an appropriate SCMCA heuristic for the case study. Following this, a sensitivity analysis is implemented to evaluate the volatility of the solutions presented by the various heuristics. Finally, a staged development scenario is proposed for the construction and expansion of facilities in California to manage the increasing rate of EoL EVBs from 2024 to 2030.M.S

    Big Data Computing for Geospatial Applications

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    The convergence of big data and geospatial computing has brought forth challenges and opportunities to Geographic Information Science with regard to geospatial data management, processing, analysis, modeling, and visualization. This book highlights recent advancements in integrating new computing approaches, spatial methods, and data management strategies to tackle geospatial big data challenges and meanwhile demonstrates opportunities for using big data for geospatial applications. Crucial to the advancements highlighted in this book is the integration of computational thinking and spatial thinking and the transformation of abstract ideas and models to concrete data structures and algorithms

    Geomatics Applications to Contemporary Social and Environmental Problems in Mexico

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    Trends in geospatial technologies have led to the development of new powerful analysis and representation techniques that involve processing of massive datasets, some unstructured, some acquired from ubiquitous sources, and some others from remotely located sensors of different kinds, all of which complement the structured information produced on a regular basis by governmental and international agencies. In this chapter, we provide both an extensive revision of such techniques and an insight of the applications of some of these techniques in various study cases in Mexico for various scales of analysis: from regional migration flows of highly qualified people at the country level and the spatio-temporal analysis of unstructured information in geotagged tweets for sentiment assessment, to more local applications of participatory cartography for policy definitions jointly between local authorities and citizens, and an automated method for three dimensional (3D) modelling and visualisation of forest inventorying with laser scanner technology

    Can We `Feel' the Temperature of Knowledge? Modelling Scientific Popularity Dynamics via Thermodynamics

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    Just like everything in the nature, scientific topics flourish and perish. While existing literature well captures article's life-cycle via citation patterns, little is known about how scientific popularity and impact evolves for a specific topic. It would be most intuitive if we could `feel' topic's activity just as we perceive the weather by temperature. Here, we conceive knowledge temperature to quantify topic overall popularity and impact through citation network dynamics. Knowledge temperature includes 2 parts. One part depicts lasting impact by assessing knowledge accumulation with an analogy between topic evolution and isobaric expansion. The other part gauges temporal changes in knowledge structure, an embodiment of short-term popularity, through the rate of entropy change with internal energy, 2 thermodynamic variables approximated via node degree and edge number. Our analysis of representative topics with size ranging from 1000 to over 30000 articles reveals that the key to flourishing is topics' ability in accumulating useful information for future knowledge generation. Topics particularly experience temperature surges when their knowledge structure is altered by influential articles. The spike is especially obvious when there appears a single non-trivial novel research focus or merging in topic structure. Overall, knowledge temperature manifests topics' distinct evolutionary cycles

    Análise de redes da paisagem submarina de canhão : implicações para o planeamento e gestão da biodiversidade

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    Submarine canyons are complex and heterogeneous geomorphologic structures highly relevant for the biodiversity and productivity of continental margins. These marine ecosystems play a key role providing invaluable goods and services for human well-being but are also increasingly subjected to the effects of anthropogenic pressure and climate change. The natural isolation of canyons may act synergistically with these changes with implications for population connectivity and the maintenance of biodiversity. The understanding of the causes and ecological consequences of such changes requires holistic and interdisciplinary approaches. I mapped the landscape of submarine canyon research based on a comprehensive bibliographic data set and using data mining techniques and network analysis. The existing knowledge clusters, historical trends, emergent topics and knowledge gaps in canyon research were identified and characterized. Topics such as “Geology & Geophysics”, “Oceanographic Processes” and “Biology & Ecology” were among the most studied while, for instance, “Biogeochemistry” and ecological modelling were among the less explored. Topics regarding anthropogenic impacts and climate-driven processes were only detected on publication of the last decade. The knowledge network reflects a latent interdisciplinarity in canyon research that developed mostly in the new millennium, supported by a well implemented and international collaboration network. The research efforts have been mainly directed towards only a few canyon systems and a thematic bias was identified, with specific topics addressed preferentially in particular canyons. This spatial and thematic bias, together with the paucity of truly inter-disciplinary studies, may be the most important limitation to the integrated knowledge and development of canyon research and hinders a global, more comprehensive understanding of canyon patterns and processes. The scientific landscape mapping and the complementary results are made available online as an open and interactive platform. In order to assess the importance of submarine canyons for the conservation and management on the deep sea, a study area and a modelling species were selected: the Mediterranean Sea and Lophelia pertusa, a cold-water coral species. The Mediterranean Sea encompasses several submarine canyon systems and L. pertusa is an ecosystem engineering species that occurs frequently in these geomorphological features and provides refuge, nursery grounds and physical support for a remarkable diversity of other life forms. Considering that the distribution of L. pertusa in the Mediterranean Sea is probably underestimated and that this information is crucial to assess the relevance of canyons in the Mediterranean seascape, I estimated the habitat suitability and draw uncertainty maps for this region based on environmental predictors and an ensemble approach of three machine-learning algorithms. The results suggest that in the Mediterranean Sea, L. pertusa encounters environmental settings close to its physiological limits but, despite the highly variable quality of the seascape, submarine canyons were identified as high suitability areas, especially across the Western and Central Mediterranean margins. In addition to the environmental suitability, the ecosystem connectivity determines the species distribution, the metapopulation dynamics and population resilience. I simulated the transport of L. pertusa larvae in the Mediterranean Sea using a biophysical model to estimate their potential dispersal as well as a network analysis to evaluate the habitat availability based on parameters such as suitability, spatial configuration of the seascape and the oceanographic conditions variability. The results suggest that connectivity among Mediterranean ecoregions is weak and that the intensification of climate-driven events (e.g., dense shelf water cascading) may worsen this scenario. However, the potential exchange of larvae between colonies within the same ecoregion was significant, favoring population resilience to local disturbances. Habitat areas with high quality and larval flux were identified as a priority for the conservation of L. pertusa, and subsequently also for their associated fauna. Once again, I showed that habitat areas on submarine canyons may play an important role in the connectivity of L. pertusa Mediterranean populations. However, these habitat areas are subjected to intense anthropogenic pressures, which allied to the effects of climate change, may impose greater challenges to their conservation. Apart from three French marine protected areas in the Gulf of Lion, the development of conservation efforts considering submarine canyon in the Mediterranean Sea is negligible. The knowledge produced in this thesis provides scientific evidence to support decision-making in conservation and planning of marine protected areas networks in the Mediterranean Sea and illustrates the relevance of submarine canyon for the management and conservation of deep-sea biodiversity.Os canhões submarinos são estruturas geomorfológicas complexas localizadas nas margens continentais. São reconhecidos como zonas importantes de biodiversidade no mar profundo onde os níveis de produtividade biológica são de modo geral superiores às áreas adjacentes. Estes ecossistemas marinhos desempenham um papel fundamental na prestação de bens e serviços essenciais ao bem-estar humano. Não obstante, estes ecossistemas estão cada vez mais sujeitos a efeitos nefastos que advêm de ações diretas das atividades humanas, mas também, resultantes de alterações climáticas. O isolamento natural dos canhões submarinos em conjunto com estas mudanças, pode ter implicações para a conectividade das populações biológicas que os habitam, bem como para a manutenção da biodiversidade associada. Avaliar as causas e efeitos ecológicos de tais mudanças só será possível através de uma abordagem holística e interdisciplinar. Partindo de uma base de dados bibliográfica abrangente de publicações dedicadas ao estudo de canhões submarinos, usei técnicas de data mining e de análise de redes para mapear o conhecimento reunido até agora. Foram identificados clusters de conhecimento, a evolução histórica da investigação em canhões submarinos, bem como, os tópicos emergentes e lacunas no conhecimento sobre estas estruturas. Os tópicos mais desenvolvidos dizem respeito a áreas associadas à “Geologia e Geofísica”, “Processos Oceanográficos” e “Biologia e Ecologia”. Por outro lado, temas como “Biogeoquímica” e modelação ecológica estão entre os menos explorados. Estudos referentes a impactos antropogénicos nestes ecossistemas e alterações induzidas por processos climáticos foram detetados apenas em publicação datadas da última década. A rede de tópicos gerada reflete uma interdisciplinaridade latente na investigação associada a canhões que se desenvolveu principalmente durante o século XXI, apoiada por colaborações internacionais da comunidade científica. No entanto, a investigação científica em canhões submarinos apresenta uma tendência clara direccionada para determinados temas e áreas geográficas. Tópicos específicos são abordados preferencialmente em determinados canhões, enquanto que um número muito pequeno destas estruturas concentra a maior parte dos trabalhos desenvolvidos. Este resultado juntamente com o número reduzido de estudos interdisciplinares, foi a mais importante limitação detetada que poderá dificultar a integração do conhecimento já reunido sobre estas estruturas, impedido uma compreensão mais abrangente dos padrões e processos associados aos canhões submarinos. Os resultados alcançados foram disponibilizados numa plataforma online aberta para exploração interativa e direcionada dos conteúdos. No sentido de avaliar a importância dos canhões para a conservação e gestão da biodiversidade no mar profundo, foi definida como área de estudo o Mar Mediterrâneo e selecionada como espécie modelo, um coral de água fria: Lophelia pertusa. O Mar Mediterrâneo engloba vários sistemas de canhões submarinos enquanto que L. pertusa é uma espécie engenheira de ecossistemas que cria refúgio, áreas de berçário e habitat para uma panóplia de outras espécies, ocorrendo frequentemente em canhões. Uma vez que a distribuição de L. pertusa no Mar Mediterrâneo está provavelmente subestimada e que esta informação é fundamental para avaliar a relevância dos canhões na área de estudo, desenvolvi um modelo de nicho ecológico baseado em variáveis ambientais e uma abordagem conjunta de três algoritmos. Os resultados obtidos foram mapas de adequação ambiental, bem como, de avaliação da capacidade de previsão do modelo. Os resultados sugerem que no mar Mediterrâneo, esta espécie de coral encontra condições ambientais próximas dos seus limites fisiológicos. Apesar disso, áreas com condições favoráveis à ocorrência de L. pertusa foram detetadas em canhões submarinos, principalmente no Mediterrâneo Ocidental e Central. A par da qualidade dos habitats, a distribuição dos organismos, a dinâmica metapopulacional e a resiliência das populações a perturbações estão fortemente relacionadas com a conectividade dos ecossistemas. Neste contexto, simulei o transporte de larvas de L. pertusa no Mar Mediterrâneo usando um modelo biofísico para estimar o seu potencial de dispersão. Com os resultados do modelo e usando análises de rede, avaliei a disponibilidade de habitat com base em parâmetros como a qualidade, configuração espacial da paisagem marinha e variabilidade oceanográfica. Os resultados sugerem que a conectividade entre as eco-regiões do Mar Mediterrâneo é baixa e que a intensificação de eventos impulsionados por condições climáticas (por exemplo, dense shelf water cascading) pode agravar este cenário. No entanto, a potencial troca de larvas entre colónias dentro da mesma eco-região foi significativa, podendo favorecer a resiliência das populações a perturbações locais. Áreas de habitat com boa qualidade e com fluxo de larvas foram identificadas como prioritárias para a conservação de L. pertusa, com benefícios eventuais também para a fauna associada a este coral. Mais uma vez, áreas de habitat incluídas em canhões submarinos foram identificadas como as mais relevantes no Mar Mediterrâneo, devendo desempenhar um papel importante na conectividade de populações desta espécie. Contudo, estas áreas estão igualmente sujeitas de forma intensa a atividades humanas com efeitos prejudiciais nos ecossistemas, e que, aliadas aos efeitos das alterações climáticas, podem dificultar a implementação de medidas de conservação eficazes. Com a exceção de três áreas marinhas protegidas francesas no Golfo do Leão, o desenvolvimento de esforços de conservação no Mar Mediterrâneo que incluam áreas com canhões submarinos é ainda negligenciável. Os resultados apresentados nesta tese fornecem evidências científicas que poderão apoiar medidas de conservação e gestão com vista à criação de redes de áreas marinhas protegidas no Mar Mediterrâneo. Neste sentido, proponho os canhões submarinos como áreas prioritárias para a conservação da biodiversidade de mar profundo na área de estudo.PEst-C/MAR/LA0017/2013 e UID/AMB/50017/2013Programa Doutoral em Biologia e Ecologia das Alterações Globai

    Data analytics 2016: proceedings of the fifth international conference on data analytics

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    LIPIcs, Volume 277, GIScience 2023, Complete Volume

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    LIPIcs, Volume 277, GIScience 2023, Complete Volum

    SIS 2017. Statistics and Data Science: new challenges, new generations

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    The 2017 SIS Conference aims to highlight the crucial role of the Statistics in Data Science. In this new domain of ‘meaning’ extracted from the data, the increasing amount of produced and available data in databases, nowadays, has brought new challenges. That involves different fields of statistics, machine learning, information and computer science, optimization, pattern recognition. These afford together a considerable contribute in the analysis of ‘Big data’, open data, relational and complex data, structured and no-structured. The interest is to collect the contributes which provide from the different domains of Statistics, in the high dimensional data quality validation, sampling extraction, dimensional reduction, pattern selection, data modelling, testing hypotheses and confirming conclusions drawn from the data

    12th International Conference on Geographic Information Science: GIScience 2023, September 12–15, 2023, Leeds, UK

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    Decadal development of CREST hydrological model family: review, improvements, applications, and outlook

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    A hydrological model is an indispensable tool in Earth system science and engineering operations to understand, predict, and manage water resources on Earth. The Coupled Routing and Excess Storage (CREST) model, released in 2011, is one such to simulate distributed hydrologic states and fluxes at variable scales. Over the last decade, CREST model has been actively under development and applied by different sectors to tackle water-related problems worldwide. This dissertation is dedicated to expanding the capacity of CREST model from three main fronts: (1) hydrologic data, (2) model development, and (3) applications. To start, the decadal development and applications of CREST model family were reviewed to lay the foundation for my contribution (Chapter 1). First, uncertainties in hydrologic input data were evaluated comprehensively for three state-of-the-science precipitation datasets derived from in-situ instruments, ground weather radar, and satellites during extreme events (Chapter 2); then a 120-year CONUS-wide flood database was compiled into a unified format as a validation source for models and hydroclimatic research (Chapter 3). From the model development front, a Hydrologic&Hydraulic (H&H) framework was developed to empower flood inundation mapping capacity for CREST (Chapter 4); furthermore, the re-infiltration, an important yet often ignored hydrologic process during the flooding period, was incorporated to improve the more realistic rainfall-runoff modeling representation (Chapter 5). To further improve the model efficiency, a vector-based CREST model was developed that can achieve 10x speedup for a continental-scale simulation, as well as improved model accuracy (Chapter 6). Finally on the model application, the high-resolution CREST model was applied in quantifying future US floods in a warmer climate: flood flashiness is becoming 7.9% higher for the continent (Chapter 7); and extreme rainfall and floods are becoming more frequent, widespread, and less seasonal (Chapter 8). The final Chapter 9 summarizes the contributions to the CREST model family development, outlooks, and general remarks for advancing our understanding of hydrologic science and engineering
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