Blockchain technology emerged in 2009 together with the introduction of Bitcoin, the first virtual currency which enabled nodes in a network, that do not necessarily trust each other, to exchange digital value without the use of trusted intermediaries. Since then, the idea of disintermediation and decentralization has gained traction in a large number of applications outside the world of finance and virtual currencies. This thesis is written in collaboration with Scania, an automotive industry manufacturer, with the purpose of gaining a better understanding of blockchain technology and how it can be used in the transportation industry. This thesis proposes five potential blockchain use cases that aim to either enhance Scania’s existing services or to create new services. Out of these five use cases, one is deemed inappropriate in regards to the use of blockchain technology while the other four have potentials benefits. The common denominator among these use cases is that they are decentralized in nature meaning that the use of intermediaries is mitigated. It is recognized that all use cases could be implemented using traditional, centralized databases and that the use of blockchain boils down to a technology choice with its own trade-offs relative to other potential choices. This thesis concludes that blockchain technology offers a new kind of database architecture, the main benefit of which is that it lets several non-trusting entities agree on a common set of facts, without having a trusted intermediary establishing these facts.

O registro sedimentar do final do Neoproterozóico tem sido alvo de intensas pesquisas desde a retomada dos modelos de glaciação extrema e rápidas mudanças climáticas, com destaque para a hipótese Snowball Earth. Esses modelos baseiam-se na identificação, em todos os continentes, de sucessões neoproterozóicas que compreendem diamictitos sobrepostos por carbonatos, interpretados, respectivamente, como depósitos glaciais e pós-glaciais. A fim de explicar o caráter global da distribuição dos diamictitos e sua aparente transição rápida para carbonatos, alguns autores propuseram hipóteses de que o planeta teria sofrido mudanças climáticas extremas, e de que estas teriam ocorrido na forma de três eventos glaciais durante o Criogeniano e o Ediacarano (Sturtian, Marinoan e Gaskiers). Outros autores consideram que a correlação global destes depósitos pode ser explicada pelo modelo Zipper-rift, que considera a existência de geleiras de altitude, condicionadas pelo soerguimento das ombreiras de sistemas de rifts, supostamente abertos durante a fragmentação do supercontinente Rodínia. Apesar de intensos esforços para correlacionar estas sucessões, ainda persistem dúvidas a esse respeito. Isto se deve, em parte, à ênfase dada ao estudo das sucessões carbonáticas sobrejacentes, em detrimento das pesquisas nos próprios diamictitos. Dentro desse contexto, o presente estudo tem como alvo a sucessão sedimentar inferior do Grupo Una, interpretada como representativa do evento Sturtian, localizada na porção norte do Cráton do São Francisco, Bahia, Brasil. Foram realizadas análises de fácies, de associações de fácies e de proveniência sedimentar com o objetivo de testar os modelos de dinâmica glacial propostos para o período e avaliar localmente o caráter da transição entre diamictitos e carbonatos. O Grupo Una apresenta área de afloramento de aproximadamente 16.000 km2 e compreende depósitos sedimentares isentos de metamorfismo, que se encontram distribuídos em três sinclinais (Salitre, Irecê e Una-Utinga). Na base, compreende arenitos, diamictitos e pelitos com clastos esparsos da Formação Bebedouro, interpretada em termos das associações de fácies (1) Transicional marinha influenciada por banquisas e/ou icebergs e (2) Marinha de plataforma continental. A passagem para a unidade de topo ocorre de forma brusca, em contato plano com dolomitos maciços a laminados com pseudomorfos de aragonita, sobrepostos por ritmitos de calcarenitos e calcilutitos com laminação planoparalela, laminação cruzada cavalgante, estromatólitos e slumps, dividos nas associações de fácies de (3) Plataforma carbonática rasa influenciada por ondas e (4) Rampa carbonática influenciada por escorregamentos. Dados de contagem de litotipos em clastos e seções delgadas indicam variação lateral de proveniência, com fontes particulares para cada uma das áreas investigadas. Essa variação é interpretada como resultado de aporte de geleiras de vale ou do tipo outlet na margem glacio-marinha, indicando a presença de altos topográficos. A datação U-Pb SHRIMP de seixos revelou predomínio de fontes próximas, com contribuição local de fontes mais distantes, sugerindo alguma deposição a partir de icebergs provenientes da margem oposta da bacia, talvez a mais de 150 km à leste, sobre os Blocos Jequié ou Itabuna-Salvador- Curaçá. Datações de cristais de zircão detrítico da matriz dos diamictitos confirmam os dados obtidos a partir de seixos, e permitem a identificação de uma fonte jovem, de fora do cráton, com cerca de 850 Ma. Esse dado limita a idade máxima da unidade. Ainda que a proveniência da Formação Bebedouro indique a existência de altos topográficos adjacentes à bacia, a ausência de controles tectônicos na sedimentação, evidenciada pela grande persistência lateral de sistemas deposicionais com pouca variação de espessura, não corrobora o modelo de desenvolvimento das geleiras neoproterozóicas em margens de sistemas de rifts. / The sedimentary record of Neoproterozoic age has become a major subject of research since the rebirth of the models of extreme glaciation and rapid climatic changes for the period, including the Snowball Earth hypothesis. These models are founded on the identification, in all continents, of Neoproterozoic diamictites directly overlain by carbonates, which are interpreted respectively as glacial and post-glacial deposits. In order to explain the global distribution of diamictites and their apparently rapid transition to carbonates, some authors have proposed hypothesis of extreme climatic change related to three glacial episodes during the Cryogenian and the Ediacaran (Sturtian, Marinoan e Gaskiers). On the other hand, some authors consider that the global correlation of these deposits is the consequence of altitude-nucleated glaciers formed on the shoulders of rift systems during the breakup of the Rodinia Supercontinent, in what is called the Zipper-rift model. Despite the efforts to establish a chronological correlation among the several successions, many questions still persist, in part due to the great emphasis on the study of the carbonate successions and the scarce work on the diamictites. The present work aims at studding the lower section of the Una Group, interpreted as related to the Sturtian glacial event and located in the northern region of the São Francisco Craton, Bahia, Brazil. Facies, facies associations and clastic provenance analysis were performed in order to test the current models on the Neoproterozoic glacial dynamics and to locally evaluate the passage from diamictites to carbonates. The Una Group crops out in a area of approximately 16,000 km2 and is composed of sedimentary deposits without metamorphism, preserved in three synclinal folds (Salitre, Irece e Una-Utinga). At its base, the unit comprises sandstones, diamictites and mudstones with dropstones grouped into the Bebedouro Formation. This formation comprises two facies associations: (1) Marine transitional deposits influenced by ice-shelves and/or icebergs and (2) Continental platform marine deposits. The passage to the upper unit is marked by a sharp planar surface above which lay two facies associations: (3) Wave influenced shallow carbonatic platform deposits, comprising massive to laminated dolomites, locally with aragonite pseudomorph crystals, overlain by (4) Carbonatic ramp influenced by slumps, composed of calcareous grainstones and mudstones with plane-parallel lamination, climbing ripples, slump structures and locally stromatolites. Pebble lithology and thin section compositional data indicate great spatial variation of provenance, with specific sources for each of the investigated areas. This variation is interpreted as the consequence of valley or outlet glaciers feeding the glaciomarine margin, thus indicating the presence of topographically elevated areas near the basin. U-Pb SHRIMP dating of selected pebbles reveals the dominance of nearby sources, with the local contribution of far-traveled clasts, suggesting mixing with sediments deposited from icebergs which came from the opposite basin margin, as far as 150 km to the east. U-Pb SHRIMP dating of detrital zircon grains from the matrix of the diamictites confirmed this model and lead to the identification of a source from outside the craton with approximately 850 Ma. This data constraints the maximum depositional age of the Bebedouro Formation. Despite provenance from the Bebedouro Formation indicates the presence of topographically elevated areas near the basin, the absence of tectonic controls on the sedimentation, evidenced by the great lateral continuity of the depositional systems and their small thickness variation, does not confirm the model of development of neoproterozoic glaciers over the shoulders of rift systems.

This work presents new method for determination of geological provenance based on the statistical analysis of cathodoluminescence spectra of marbles and carbonate rocks from various localities in the Bohemian Massif. Analysis is based on the combination of data from seven different measures of spectral similarity and provides results that are more robust than those obtained by approach based only on a single measure of similarity. These results may be further improved by employing meta-analysis that evaluates behaviour of spectra during the individual steps of analysis. Analysis was performed on the original cathodoluminescence spectra, as well as on the residual spectra in which relative variability was amplified by the subtraction of Gaussian trend present in all spectra of carbonates. By combining results from analysis and meta-analysis of both original and residual spectra it was possible to almost unambiguously determine provenance of samples from all studied localities. Agglomerative hierarchical clustering was employed as a supplementary method for classification of spectra. Out of 72 different methods for clustering, one was selected for both original and residual data based on the number of correctly classified spectra. Second part of this work presents analysis of cathodoluminescence...

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>Magister Scientiae - MSc / Southern offshore basins of South Africa are well known as potential provinces of hydrocarbon exploration and production. The complex nature of the Bredasdorp sub-basin’s syn-rift architecture (transform fault system) can have adverse effects on reservoir distribution due to periodic local and regional uplift of horsts and grabens. This present investigation focusses on an integrated approach of the 1AT1-V horizon or early Cretaceous sediments in the Bredasdorp sub-basin to identify the depositional environment and provenance of these sediments as well as their role in regionally complex compositional heterogeneities associated with the late stage rifting of Gondwana break-up. An integrated seismic, sedimentological (including petrography and geochemistry) and ichnologic analysis of the 1AT1-V horizon sediments showed an overall lower regressive element complex assemblage set and an upper transgressive element complex assemblage set that occurred as a >120m thick succession. The analysis identified a mixed-energy deltaic succession followed by an estuarine succession. The 1AT1-V interval (late syn-rift) consisted of nine sedimentary facies associations (and associated petrofacies) on a dipslope setting with variations occurring along the strike and the downdip depositional slope areas. Two overall sequences were identified as a lower regressive and upper transgressive sequence (Element complex assemblage sets). The regressive sequence consisted of middle to distal delta front lobe fringes, hyperpycnal event beds (sourced from basement highs), offshore migrating tidal bars (and associated inter-bar regions), distal mouth bars, terminal distributary channels (and associated inter-terminal distributary regions). The distal delta plain to proximal delta front consisted of interdistributary bays, distributary channels, crevasse splay sub-deltas, mouth bars, tidal flats and offshore embayments. In the laterally isolated depocenter, these deposits also consisted of basement high slopes with upliftment of the basement highs leading to proximal/central embayment to regressive shoreface/foreshore environments. These sequences consisted generally of low diversity and intensities (impoverished abundances) of trace fossils. The paleoclimate inference from this sequence indicates a humid climate with intermediate degrees of weathering intensities (possibly fluctuating arid-humid conditions). The transgressive sequence consisted of estuarine sedimentation with the occurrence of tidal sand ridges and compound dune fields, embayment facies and tidal bars. These sequences consisted of relatively higher ichnodiversities and intensities than their relative regressive sequences. The paleoclimate inference during these times consisted of more arid to semi-arid settings with low degrees of weathering in the source terrain. Local tectonic upliftment and subsidence, with exposed basement highs, gave rise to differential process regimes (tidal, wave and fluvial) and hence depositional facies in the diachronous updip/downdip areas (spatial) and within-stratigraphic (temporal) variations. There are several modern analogues that are similar to the 1AT1-V horizon sequence and they are the Mahakam, Ganges-Brahmaputra, Po, Burdekin deltaic and Satpara lake environments Compaction and dissolution diagenetic features as well as transportation were responsible for the major compositional heterogeneities concerning the reservoir quality and distribution. Proximal and distal sources were identified with first cycle and polycyclic sediments being deposited in the northern and southern part of the basin during the late stages of rifting in the Bredasdorp sub-basin. The provenance lithology has been identified as recycled sedimentary rocks (and their meta-equivalents) with an ultimate source terrain that was largely felsic in nature (Cape granite suite). The northern part of the studied section is suggested to have received sediments from the main metasedimentary rocks of the Cape fold belt (including the Table Mountain Group and Bokkeveld Group) whereas the southern sections received more sediments from the basement highs (recycled Malmesbury Group (and Pre-Cape sediments) and Cape granite suite), which is further supported by seismic data. Provenance analysis revealed that the Cape Fold belt (most recent collision) was possibly a provenance terrain but overprinting of several collisions are also acknowledged. The tectonic setting was envisaged to be of a rifted margin during the break-up of Gondwana. This compositional heterogeneity due to facies and provenance-related terrains had major consequences to the reservoir quality and distribution from the northern part to the southern part of the studied section

Science is changing. Computers, fast communication, and  new technologies have created new ways of conducting research.  For  instance, researchers from different disciplines are processing and  analyzing scientific data that is increasing at an exponential rate.  This kind of research requires that the scientists have access to  tools that can handle huge amounts of data, enable access to vast  computational resources, and support the collaboration of large  teams of scientists. This thesis focuses on tools that help support  scientific collaboration. Workflows and provenance are two concepts that have proven useful in  supporting scientific collaboration.  Workflows provide a formal  specification of scientific experiments, and provenance offers a  model for documenting data and process dependencies.  Together, they  enable the creation of tools that can support collaboration through  the whole scientific life-cycle, from specification of experiments  to validation of results.  However, existing models for workflows  and provenance are often specific to particular tasks and tools.  This makes it hard to analyze the history of data that has been  generated over several application areas by different tools.  Moreover, workflow design is a time-consuming process and often  requires extensive knowledge of the tools involved and collaboration  with researchers with different expertise. This thesis addresses  these problems. Our first contribution is a study of the differences between two  approaches to interoperability between provenance models: direct  data conversion, and mediation. We perform a case study where we  integrate three different provenance models using the mediation  approach, and show the advantages compared to data conversion.  Our  second contribution serves to support workflow design by allowing  multiple users to concurrently design workflows. Current workflow  tools lack the ability for users to work simultaneously on the same  workflow.  We propose a method that uses the provenance of workflow  evolution to enable real-time collaborative design of workflows.  Our third contribution considers supporting workflow design by  reusing existing workflows. Workflow collections for reuse are  available, but more efficient methods for generating summaries of  search results are still needed. We explore new summarization  strategies that considers the workflow structure. <img src="data:image/png;base64,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%3D" />

This thesis describes a data provenance framework and other associated frameworks for utilizing provenance for data quality and reproducibility. We first identify the requirements for the design of a comprehensive provenance framework which can be applicable to various applications, supports a rich set of provenance metadata, and is interoperable with other provenance management systems. We then design and develop a provenance framework, called SimP, addressing such requirements. Next, we present four prominent applications and investigate how provenance data can be beneficial to such applications. The first application is the quality assessment of access control policies. Towards this, we design and implement the ProFact framework which uses provenance techniques for collecting comprehensive data about actions which were either triggered due to a network context or a user (i.e., a human or a device) action. Provenance data are used to determine whether the policies meet the quality requirements. ProFact includes two approaches for policy analysis: structure-based and classification-based. For the structure-based approach, we design tree structures to organize and assess the policy set efficiently. For the classification-based approach, we employ several classification techniques to learn the characteristics of policies and predict their quality. In addition, ProFact supports policy evolution and the assessment of its impact on the policy quality. The second application is workflow reproducibility. Towards this, we implement ProWS which is a provenance-based architecture for retrieving workflows. Specifically, ProWS transforms data provenance into workflows and then organizes data into a set of indexes to support efficient querying mechanisms. ProWS supports composite queries on three types of search criteria: keywords of workflow tasks, patterns of workflow structure, and metadata about workflows (e.g., how often a workflow was used). The third application is the access control policy reproducibility. Towards this, we propose a novel framework, Polisma, which generates attribute-based access control policies from data, namely from logs of historical access requests and their corresponding decisions. Polisma combines data mining, statistical, and machine learning techniques, and capitalizes on potential context information obtained from external sources (e.g., LDAP directories) to enhance the learning process. The fourth application is the policy reproducibility by utilizing knowledge and experience transferability. Towards this, we propose a novel framework, FLAP, which transfer attribute-based access control policies between different parties in a collaborative environment, while considering the challenges of minimal sharing of data and support policy adaptation to address conflict. All frameworks are evaluated with respect to performance and accuracy.

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Petrographic and age analysis of sandstones, detailed structural analysis and gravity modeling were conducted to investigate the origin of the Gondwana Sequence in the Timor Region, and to better constrain the tectonic evolution of the active Banda Arc. Our field studies and U/Pb zircon age analysis helped assign most units to either Asian or Australian affinity. Detrital zircon from uplifted Banda forearc units (Asian affinity) have U/Pb ages as young as 80 Ma (Standley and Harris, in press). In contrast, analysis of detrital zircon from Gondwana Sequence sandstones accreted to the Banda Arc from Savu to East Timor are no younger than 234.6 ± 4.0 Ma, and have peak ages at 301 Ma and 1873 Ma with some Archean ages. These age constraints provide a reliable new application for distinguishing rocks units as Asian or Australian affinity. Petrographic and provenance analysis of Triassic Australian affinity greywacke units yield QFL abundances consistent with a proximal, syn-rift, intracratonic or recycled orogen source, from the northeast. The Mount Isa region to the east has the most similar peak U/Pb zircon ages to the Gondwana Sequence. However an extension of this terrane to the west, which would have rifted away during Jurassic breakup, is required to account for the immaturity of the sandstones. Structural measurements of Gondwana Sequence units accreted to the Banda Arc show a northwest - southeast paleo and current maximum stress direction, and vergence mostly to the southeast. Individual thrust sheets are 3 km thick and account for 50% total shortening. The deformational grain of Timor is a hybrid of the east-west strike of Banda Arc and northeast-southwest strike of incoming Australian continental margin structures. The Banda forearc, which is 200 km wide north of Savu, progressively narrows towards East Timor. In order to constrain the location of the forearc, three area-balanced structural models were tested against the gravity field of the Banda Arc. The best fit model requires internal shortening and under-stacking of the forearc beneath the arc, which may account for the cessation of volcanism and uplifted coral terraces north of East Timor.