5 research outputs found

    Modeling of soil weathering on hillslopes : coping with nonlinearity and coupled processes using a data-driven approach

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    Orientadores: Carlos Roberto de Souza Filho, Michael James FriedelTese (doutorado) - Universidade Estadual de Campinas, Instituto de GeociênciasResumo: Esta tese de doutorado tem como objetivo aprofundar o conhecimento sobre as relações das propriedades físico-quimicas do solo com a morfometria do relevo, buscando quantificar essas relações para a construção de modelos conceituais e preditivos. Mapas auto-organizáveis e modelos de sistemas de informação geográfica foram utilizados para investigar as relações não lineares associadas ao intemperismo químico e físico, fatores associados a fenômenos hidrológicos e à evolução dos solos. Três estudos de caso são apresentados: o intemperismo químico de solo no estado do Paraná (22 variáveis e 304 amostras), o transporte físico de sedimentos em Poços de Caldas (9 variáveis e 29 amostras), e hidroquímica de aqüíferos na Formação Serra Geral no Estado do Paraná (27 variáveis e 976 amostras). O método combinando simulação estocástica e mineração de dados permitiu explorar as relações entre relevo, granulometria e geoquímica dos solos. Regiões mais elevadas e com morfometria convexa apresentaram alta denudação de elementos móveis (e.g., Ca) e baixa de elementos pouco móveis (e.g., Al). O mesmo padrão foi observado para granulometria de solos, ou seja, alta proporção de areia em áreas altas e convexas da bacia e altos teores de argila, com baixa condutividade hidráulica, em regiões convexas próximas aos canais de drenagem. O comportamento espacial da hidroquímica das águas do aqüífero Serra Geral apontou áreas de potencial conectividade entre aqüíferos, áreas de recarga recente e de alto tempo de residência. Foram construídos modelos preditivos não tendenciosos das propriedades do solo em subsuperfície partindo da premissa de que o intemperismo e a morfometria se relacionam através de um processo duplamente dependente, onde a denudação física e química atua no delineamento do relevo e a morfometria do terreno é um fator que caracteriza as condições físico-químicas do soloAbstract: This Doctoral thesis aims to explore the relationship between soil physical-chemical properties and relief morphometry, and quantifying these relationships to build conceptual and predictive models. Self-organizing maps and Geographic Information Systems modeling are here used to investigate nonlinear correlations associated with chemical and physical denudation; which are factors connected with hydrological phenomena and soil evolution. Three study cases are presented: soil chemical weathering within the limits of the Parana State, southern Brazil (22 variables and 304 samples), physical transport of sediments in the alkaline intrusive complex of Poços de Caldas, southeastern Brazil (9 variables and 29 samples), and hydrochemistry of Serra Geral aquifers also in the Parana State (27 variables and 976 samples). The method combining stochastic simulation and data mining allows exploring the relationships between topography, soil texture and soil geochemistry. In the Parana State, higher regions and areas with convex morphometry shows, respectively, higher and lower denudation rates of mobile (e.g., Ca) and less mobile (e.g., Al) elements. The same pattern is observed for soil particle size. In this case, high proportion of sand is found in highlands and convex areas inside the basin, and high clay content, with low hydraulic conductivity, occurs in convex regions, near drainage channels. The spatial behavior of the Serra Geral aquifer?s hydrochemistry pointed out to areas with potential connectivity with the Guarani aquifer system, recent recharge areas, and long-standing waters. Predictive, unbiased models are built for soil properties on the premise that weathering and morphology are related through a two-way dependent process, where the physical and chemical denudation delineates the elevations of the land surface, and terrain morphometry is a factor that characterizes the physical-chemical conditions of the soilDoutoradoGeologia e Recursos NaturaisDoutor em Ciência

    Visual and Camera Sensors

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    This book includes 13 papers published in Special Issue ("Visual and Camera Sensors") of the journal Sensors. The goal of this Special Issue was to invite high-quality, state-of-the-art research papers dealing with challenging issues in visual and camera sensors

    Progress in Landslide Research and Technology, Volume 1 Issue 2, 2022

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    This open access book provides an overview of the progress in landslide research and technology and is part of a book series of the International Consortium on Landslides (ICL). It gives an overview of recent progress in landslide research and technology for practical applications and the benefit for the society contributing to understanding and reducing landslide disaster risk

    BIM and Knowledge Based Risk Management System

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    The use of Building Information Modelling (BIM) for construction project risk management has become a growing research trend. However, it was observed that BIM-based risk management has not been widely used in practice and two important gaps leading to this problem are: 1) very few theories exist that can explain how BIM can be aligned with traditional techniques and integrated into existing processes for project risk management; and 2) current BIM solutions have very limited support on risk communication and information management during the project development process. To overcome these limitations, this research proposes a new approach that two traditional risk management techniques, Risk Breakdown Structure (RBS) and Case-based Reasoning (CBR), can be integrated into BIM-based platforms and an active linkage between the risk information and BIM can be established to support the project lifecycle. The core motivations behind the proposed solution are: 1) a tailored RBS could be used as a knowledge-based approach to classify, store and manage the information of a risk database in a proper structure and risk information in RBS could be linked to BIM for review, visualisation and communication; and 2) knowledge and experience stored in past risk reports could contribute to avoiding similar risks in new situations and the most relevant cases can be linked to BIM to support decision making during the project lifecycle. The scope of this research is limited to bridge projects; however, the basic methods and principles could be also applied to other types of projects. This research is in three phases. In the first stage, this research analysed the conceptual separation of BIM and the linkage rules between different types of risk and BIM. Specifically, an integrated bridge information model was divided into four Level of Contents (LOCs) and six technical systems based on the analysis of the Industry Foundation Classes (IFC) specification, a critical review of previous studies and the author’s project experience. Then a knowledge-based risk database was developed through an extensive collection of risk data, a process of data mining, and further assessment and translation of the data. Built on the risk database, a tailored RBS was developed to categorise and manage this risk information and a set of linkage rules between the tailored RBS and the four LOCs and six technical systems of BIM was established. Secondly, to further implement the linkage rules, a novel method to link BIM, RBS, and Work Breakdown Structure (WBS) to be a risk management system was developed. A prototype system was created based on Navisworks and the Microsoft SQL Server to support the implementation of the proposed approach. The system allows not only the storage of risk information in a central database but also to link the related risk information in the BIM model for review, visualisation and simulation. Thirdly, to facilitate the use of previous knowledge and experience for BIM-based risk management, the research proposed an approach of combining the use of two Natural Language Processing (NLP) techniques, i.e. Vector Space Model (VSM) and semantic query expansion, and outlined a new framework for the risk case retrieval system. A prototype was developed using the Python programming language to support the implementation of the proposed method. Preliminary testing results show that the proposed system is capable of retrieving relevant cases automatically and to return, for example, the top 10 similar cases. The main contribution of this research is the approach of integrating RBS and CBR into BIM through active linkages. The practical significance of this research is that the proposed approach enables the development of BIM-based risk management software to improve the risk identification, analysis, and information management during the project development process. This research provides evidence that traditional techniques can be aligned with BIM for risk management. One significant advantage of the proposed method is to combine the benefits of both traditional techniques and BIM for lifecycle project risk management and have the minimum disruption to the existing working processes

    Landslide analysis and early warning

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    In jüngerer Vergangenheit aufgetretene gravitative Massenbewegungen verdeutlichen die Notwendigkeit die Vorhersagemöglichkeiten von und die Frühwarnung vor gravitativen Massenbewegungen zu verbessern, um die damit verbundenen Risiken zu reduzieren und Menschenleben zu schützen. Die vorliegende Arbeit beschäftigt sich mit lokalen und regionalen Analysen der auslösenden Bedingungen gravitativer Massenbewegungen an der Schwäbischen Alb, und der Entwicklung von Frühwarnsystem Prototypen. Im lokalen Untersuchungsgebiet wurde ein extensives hydrologisches und Hangbewegungsmonitoringsystem auf einem saisonal reaktivierten Hangrutschungskörper in Lichtenstein-Unterhausen installiert. Basierend auf der Analyse von Monitoringdaten wurde der Einfluss von Niederschlag und Schneeschmelze auf die Grundwasserbedingungen und die Initiierung von Hangbewegungen untersucht. Das kombinierte Hydrologie und Stabilitätsmodell CHASM wurde verwendet, um Hangbereiche auszuweisen, für die ein Versagen wahrscheinlich ist, und die Auswirkungen einer Vielzahl von Einflussfaktoren auf die Hangstabilität zu simulieren. Auf den Ergebnissen aufbauend wurden zwei Internet-basierte Anwendungen entwickelt. Die erste Applikation stellt ein technisches Frühwarnsystem dar, in dem die Hangstabilität unter Verwendung von gemessenem Niederschlag, hydrologischen Monitoringdaten und Wettervorhersagen fortlaufend simuliert wird. Die zweite Anwendung dient der Entscheidungsunterstützung und erlaubt eine schnelle Berechnung der Hangstabilität für frei wählbare Profile. Auf der regionalen Ebene wurden verfügbare Inventare gravitativer Massenbewegungen analysiert und hinsichtlich einer Bewertung von Niederschlagsschwellenwerte anderer Studien ausgewertet. Adäquate gravitative Massenbewegungen wurden ausgewählt und deren auslösende Niederschlags- und Schneeschmelzekonditionen mit Intensität-Dauer und kumulativen Schwellenwerten verglichen. Aufbauend auf den Ergebnissen wurde ein regionales Frühwarnsystem für gravitative Massenbewegungen entwickelt und als Internet-basiertes Anwendung implementiert. Die entwickelten lokalen und regionalen Frühwarnsysteme sind Teil einer holistischen und integrativen Frühwarnkette, welche durch das ILEWS Project implementiert wurde, und können auch auf andere von gravitativen Massenbewegungen betroffene Gebiete übertragen werden.Recent landslide events demonstrate the need to improve landslide forecasting and early warning capabilities in order to reduce related risks and protect human lives. In this thesis, local and regional investigations were carried out to analyse landslide characteristics in the Swabian Alb region, and to develop prototypic landslide early warning systems. In the local study area, an extensive hydrological and slope movement monitoring system was installed on a seasonally reactivated landslide body located in Lichtenstein-Unterhausen. Monitoring data was analysed to assess the influence of rainfall and snow-melt on groundwater conditions, and the initiation of slope movements. The coupled hydrology-slope stability model CHASM was applied to detect areas most prone to slope failures, and to simulate slope stability using a variety of input data. Subsequently, CHASM was refined and two web-based applications were developed: a technical early warning system to constantly simulate slope stability integrating rainfall measurements, hydrological monitoring data and weather forecasts; and a decision-support system allowing for quick calculation of stability for freely selectable slope profiles. On the regional scale, available landslide inventory data were analysed for their use in evaluation of rainfall thresholds proposed in other studies. Adequate landslide events were selected and their triggering rainfall and snow-melting conditions were compared to intensity-duration and cumulative thresholds. Based on the results, a regional landslide early warning system was developed and implemented as a web-based application. Both, the local and the regional landslide early warning systems are part of a holistic and integrative early warning chain developed by the ILEWS project, and could easily be transferred to other landslide prone areas
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