A probabilistic reasoning and learning system based on Bayesian belief networks

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Developing a hierarchical Digital Core Analysis workflow for petro-physical characterisation of cross-laminated reservoir rocks at pore scales

The study presented in this thesis addresses a critical shortfall of Digital Core Analysis (DCA) in the petro-physical characterisation of natural rock samples that exhibit complex and spatially non-separable multi-scale arrangements of mineral grains of variable sizes and chemical compositions. Since those multi-scale arrangements define non-stationary (heterogeneous) grain-pore distributions, they must be characterised on sufficiently large sample volumes for sample reconstruction at pore and grain scales, to simulate the fluid flow processes for predicting petro-physical properties. Such characterisations can only be done in a multi-stage manner at multi-scales and multi-locations on a sample, due to the mutual constraints of the imaging field of view and resolution. Typical multi-scale approaches fuse images from various sources based on shared features (e.g. disproportionately large grains) as cross-scale references, but have limited application when the shared features are less obvious (non-separable) across multi-scale images. For common cross-lamination in sandstone rocks that exhibit hierarchical structures controlling grain-pore distribution and are demarcated by physical features such as inter/intra-lamina (set) bounding surfaces, a multi-scale DCA workflow would be ideally suited for the petro-physical characterisation but would be challenging to apply when the visibility of cross-scale shared features (bounding surfaces) is weak. This work argues that the workflow needs to have the following elements: 1) a multiscale spatial sampling/characterisation procedure; 2) a way to maintain correct cross-scale spatial correlation among individual sampled datasets through shared features, as reference to the same sample, and 3) a stochastic reconstruction procedure that honours the multiscale structures identified in 1) and correlated in 2), and reconstructs the poregrain-scale non-stationarity they expressed across the correlated datasets. The work presented in this thesis focuses on cross-lamination in sandstone rocks to identify challenges arising to multi-scale characterisation and to develop a suitable hierarchical DCA workflow. For this purpose, an outcrop tight Aeolian cross-laminated sandstone sample of 6x6x6 cm3 that includes representative hierarchical structures was chosen. The key achievements are: 1) a suitable imaging-based exploratory and recursive sampling and characterisation procedure to maximise correlation between datasets. Analysis on the resultant multi-scale datasets showed that sharp and gradual grain compositions change between adjacent laminasets (inter-laminaset) and laminae (intra-laminaset), respectively, to form thin but finite-thickness bounding surfaces, which are ideally suited as shared physical features. However, challenges are identified including a) the inter-laminaset bounding surfaces are obscured by “artefacts” and cannot be enhanced by existing techniques and b) intra-laminaset bounding surfaces are hard to be even observed because of gradual composition variation. 2) To identify the two types of bounding surfaces as shared features to help registration, two new techniques were developed by exploring geological knowledge on structural morphology and mineral compositions, respectively, and were shown to be able to successfully identify and extract shared inter- and intra-laminaset bounding surfaces. 3) For a pair of realisations of sampled inter- and intra-laminaset bounding surfaces and estimated grain-pore distribution information, a non-stationary index map of grain texture (size and orientation) on the whole sample domain can be constructed to define the mean of affinity transformations for stochastically populating stationary (homogeneous) grain and pore structures by a reconstruction method which is implemented based on Multiple Points Statistics (MPS). One reconstructed pore-grain model was obtained in this work and contains 11900x11900x11900 voxels at a voxel resolution of 4 µm. This model was verified to capture key pore-grain variations associated with the characterised lamination structures

Three social science disciplines in Central and Eastern Europe: handbook on economics, political science and sociology (1989-2001)

Content: Ulrike Becker, Max Kaase, Gabor Klaniczay, and Vera Sparschuh: Social Sciences in Central and Eastern Europe on the Verge of EU Enlargement (7-10); Andrei Plesu: Financing Difference. Fostering the Social Sciences in the Field of Tension Between Homogenization and Differentiation (12-16); Elemer Henkiss: Brilliant Ideas or Brilliant Errors? (17-24); Janos Matyas Kovacs: Business as (Un)usual (26-33); Mitko Dimitrov: Bulgaria (34-49); Frantisek Turnovec: Czech Republic (50-64); Tiia Püss: Estonia (65-82); Laszlo Csaba: Hungary (83-101); Raita Karnite: Latvia (102-120); Linas Cekanavicius: Lithuania (121-134); Tadeusz Kowalik: Poland (135-151); Paul Dragos Aligica: Romania (152-167); Julius Horvath: Slovakia (168-186); Joze Mencinger: Slovenia (187-194); Hans-Jürgen Wagener: Demand and Supply of Economic Knowledge in Transition Countries (195-203); Hans-Dieter Klingemann: Political Science in Central and Eastern Europe: National Development and International Integration (206-212); Georgi Karasimeonov: Bulgaria (213-225); Jan Holzer and Pavel Pseja: Czech Republic (226-245); Raivo Vetik: Estonia (246-257); Mate Szabo: Hungary (258-274); Andris Runcis: Latvia (275-285); Algis Krupavicius: Lithuania (286-305); Stanislaw Gebethner and Radoslaw Markowski: Poland (306-321); Daniel Barbu: Romania (322-342); Darina Malova and Silvia Mihalikova: Slovakia (343-357); Danica Fink-Hafner: Slovenia (358-374); Pal Tamas: Followers or Activists? Social Scientists in the Reality Shows of Transformation (376-385); Nikolai Genov: Bulgaria (386-404); Michal Illner: Czech Republic (405-424); Mikk Titma: Estonia (425-436); Denes Nemedi and Peter Robert: Hungary (437-451); Aivars Tabuns: Latvia (452-466); Anele Vosyliute: Lithuania (467-483); Janusz Mucha and Pawel Zalecki: Poland (484-501); Maria Larionescu: Romania (502-517); Zuzana Kusa, Bohumil Buzik, Ludovit Turcan and Robert Klobucky: Slovakia (518-535); Frane Adam and Matej Makarovic: Slovenia (536-547); Piotr Sztompka: The Condition of Sociology in East-Central Europe (548-556); Mihaly Sarkany: Cultural and Social Anthropology in Central and Eastern Europe (558-566); Thomas Kucera and Olga Kucerova: Population science in Central and Eastern Europe: Implications for Research and Practice (567-577); Marie-Claude Maurel: Central European Geography and the Post-Socialist Transformation. A Western Point of View (578-587); Grazyna Skapska: Law and Society in a Natural Laboratory: the Case of Poland in the Broader Context of East-Central Europe (588-603)

University Catalog 1988-1990

This catalog is published for students and other persons who want to know more about the University of Northern Iowa. Its purpose is to communicate as objectively and completely as possible what the university is and what it does. The catalog is presented in sections to give a general view of the university as well as the detailed information required for informed decision making.https://scholarworks.uni.edu/uni_catalogs/1017/thumbnail.jp

Aspects of Rational Structural Design of SWATH Ships

The aim of the work described herein is to provide the background, underlying assumptions and considerations, as well as describe the tools necessary for the development of reliability-based strength criteria for the design of the structural components of fast, multi-hulled ships (Chapters 1-4) in general, and SWATH ships in particular. An overall view of the current state and future prospects of the fast marine transportation market, highlighting the limitations and advantages of the application of such advanced marine concepts is provided in Chapter 1. The challenges, both strategic and technological, that would have to be overcome before these concepts enjoy a more widespread acceptance from the passengers, operators, and governments, are identified and form the background within which the work described herein develops. It has been inevitable that a large number of topics had to be covered in order to provide the reader with the overall picture of the structural design problems expected and their solutions in this novel form of transportation. As a result, no claim for completeness is made herein, but instead an 'in width' study of the topic was felt as most appropriate for establishing the degree of interrelation and interaction of the various aspects of structural design, and has therefore been actively pursued. The problem of estimation of both primary and secondary loads on SWATH ships is tackled in Chapter 2, by reviewing the options and methods available to the designer. Of the secondary loads, the question of slamming load prediction on the underdeck of SWATH ships has been given some attention, via two sets of drop tests (one by the author) carried out at the Department of Naval Architecture and Ocean Engineering, University of Glasgow and the main results described herein. Current approaches for the determination of fatigue damage loading are also described. Chapter 3 concentrates on the strength modelling aspects and the associated uncertainty as applicable to the fatigue design of both monohull and multi-hull vessels. A brief description of the sources of fatigue strength reduction in welded structures and the possible repair measures, the background to the major steel and aluminium fatigue design codes is presented, coupled with a comparison of the major aluminium fatigue design codes. The probabilistic derivation of partial safety factors for fatigue strength expressions is also presented but not demonstrated. In Chapter 4, the work has concentrated mainly in the area of strength modelling for the various structural components of the SWATH ship under all possible load combinations they might be expected to withstand. Although it stops just short of deriving appropriate partial safety factors for the various structural components and failure modes in a multi-hull structure, detailed guidance on how to do so is provided. The reliability-based design procedure to the structural optimisation, with respect to cost, weight and safety, of an example SWATH ship, the M.V. Patria is applied and described instead in Chapter 5. The conclusions of the research, recommendations on the most appropriate strength formulations and the areas which may benefit from further research are all finally identified in Chapter 6. Note: Description of the various parameters used in individual Chapters is adequately covered in the Notation Section, unless otherwise presented in the text