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Structural Mapping of Paper Towels: Comparison of Twin Laser Profilometry and Synchrotron X-ray Micro-computed TomographyHuang, Yan 17 August 2010 (has links)
No description available.
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Analysis of retinal vessel networks using quantitative descriptors of vascular morphologyJoshi, Vinayak Shivkumar 01 July 2012 (has links)
Abnormalities in the vascular pattern of a retina, such as morphologic changes in vessel shape, branching pattern, width, tortuosity, or the appearance of retinal lesions, may be associated with the occurrence of retinopathies or cardiovascular diseases. Thus, an automated quantitative analysis of changes in vessel morphology may help indicating the clinical signs of aforementioned retinopathies, describing their early occurrence or severity. The responses obtained from different types of retinal vessels, i.e., arteries and veins, may be variable to retinopathies and their measurement may lead to a more precise diagnosis compared to that by the average response accounted for the entire vessel network.
I propose a set of automated methods in order to analyze the retinal vessel network and to quantify its morphologic properties with respect to arteries and veins, in two-dimensional color fundus images. The analytical methods include; 1) Forma- tion of a well connected vessel network, 2) Structural mapping of a vessel network, 3) Artery-venous classification, and 4) Blood vessel hemorrhage detection. The quan- tification methods include vessel morphology analysis based on the measurement of tortuosity, width, branching angle, branching coefficient, and fractal dimension. The aforementioned morphologic parameters are measured with respect to arteries and veins separately in a vessel network. The methods are validated with the manually annotated retinal fundus images as a ground truth.
The major contribution of this thesis includes the development of automated methods for; 1) Identification and separation of retinal vessel trees for individual vessel analysis, 2) Automated quantification of morphologic characteristics of retinal vessels for quick and precise measurement, 3) Automated quantification of vessel morphology with respect to arteries and veins, and 4) Analysis of two datasets, a) malarial retinopathy subject dataset, b) longitudinal study dataset. The ability of the automated methods to quantify the retinal vessel specific properties may enable the individual vessel analysis as an alternative to a time- consuming and subjective clinical evaluation, or to a quantitative morphology char- acterization averaged over the entire vessel network. The objective evaluation may indicate the progression of retinopathies precisely and may help characterizing nor- mal and abnormal vascular patterns with respect to arteries and veins. This may enable a quick diagnosis, treatment availability, prognosis, and facilitation of clinical health-care procedures in remote areas.
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L’identification des opportunités d’investissement en incertitude : le jugement intuitif des Business Angels dans le financement des firmes entrepreneuriales / Investment opportunity identification under uncertainty : the business angels’s intuiting in entrepreneurial firms financingOla, Abdel Malik 12 December 2016 (has links)
Nous analysons l’identification des opportunités d’investissement dans le cas spécifique du financement de l’amorçage des firmes porteuses d’innovation. L’absence d’informations pertinentes et objectives au démarrage remet en cause la capacité postulée des investisseurs à évaluer objectivement la rentabilité des firmes entrepreneuriales. Ainsi, nous étudions la vraie stratégie psycho-cognitive sous-jacente à la création du sens autour du potentiel des projets en se focalisant sur un acteur spécifique, le Business Angel (BA). Nous postulons que cet investissement suit un processus de jugement intuitif. L’analyse qualitative des notes d’observation et des entretiens permet de construire un modèle décrivant la manière dont le BA produit in situ de nouveaux construits utiles dans sa perception. Nous mettons aussi en évidence des comportements réflexifs réduisant l’erreur dans sa décision. Ainsi, l’intuition du BA doit être vue comme une réelle approche de transformation situationnelle d’indicateurs à travers des manipulations langagières. Nous offrons une nouvelle perspective dans la compréhension du comportement des capital-risqueurs qui sont susceptibles d’accompagner financièrement les firmes innovantes dès leur phase de démarrage. Nos résultats sont aussi généralisables à des contexte où l’aptitude intuitive devant une source d’efficience décisionnelle. Nous faisons des propositions théoriques qui orienteront les études futures. / We analyze the investment opportunities’s identification in the specific case of the innovative firm financing. The absence of relevant and objective informations at the early stage weaken the investor’s postulated ability inestimating objectively the profitability of the entrepreneurial firms. Then, we study the real cognitivestrategy underlying the sensemaking process around the potential of the projects by focusing on a specific actor, the Business angel (BA). We argue that this investment follows a process of intuitive judgment.The research design is a qualitative inductive approach with data collected by observation and interviews. We build a model of how the BA cognitively interpret the innovative firm’s potential in order to invest. We highlight also cognitive practices in reducting biais and errors during the sensemaking process. The BA’s intuition atearly stage must be viewed as a processus of meaning construction through labelling and speech articulation. This thesis contributes to a better understanding ofventure capitalist behaviors at early stage as well as a better comprehension of how meaning can be created intuitively in uncertain context. Theoretical propositions are made for future researchs.
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An Approach to Mapping of Shallow Petroleum Reservoirs Using Integrated Conventional 3D and Shallow P- and SH-Wave Seismic Reflection Methods at Teapot Dome Field in Casper, WyomingOkojie-Ayoro, Anita Onohuome 17 November 2007 (has links) (PDF)
Using the famous Teapot Dome oil field in Casper, Wyoming, USA as a test case, we demonstrate how high-resolution compressional (P) and horizontally polarized shear (SH) wave seismic reflection surveys can overcome the limitations of conventional 3D seismic data in resolving small-scale structures in the very shallow subsurface (< 100-200 m (~328-656 ft)). We accomplish this by using small CMP intervals (5 ft and 2.5 ft, respectively) and a higher frequency source. The integration of the two high-resolution seismic methods enhances the detection and mapping of fine-scale deformation and stratigraphic features at shallow depth that cannot be imaged by conventional seismic methods. Further, when these two high-resolution seismic methods are integrated with 3D data, correlated drill hole logs, and outcrop mapping and trenching, a clearer picture of both very shallow reservoirs and the relationship between deep and shallow faults can be observed. For example, we show that the Shannon reservoir, which is the shallowest petroleum reservoir at Teapot Dome (depth to the top of this interval ranging from 76-198 m (250-650 ft)) can only be imaged properly with high-resolution seismic methods. Further, northeast-striking faults are identified in shallow sections within Teapot Dome. The strike of these faults is approximately orthogonal to the hinge of Teapot Dome. These faults are interpreted as fold accommodation faults. Vertical displacements across these faults range from 10 to 40 m (~33 to 131 ft), which could potentially partition the Shannon reservoir. The integration of 3D and high-resolution P-wave seismic interpretation helped us determine that some of the northeast-striking faults relate to deeper faults. This indicates that some deeper faults that are orthogonal to the fold hinge cut through the shallow Shannon reservoir. Such an observation would be important for understanding the effect on fluid communication between the deep and shallow reservoirs via these faults. Furthermore, the high-resolution seismic data provide a means to better constrain the location of faults mapped from drill hole logs. Relocation of theses faults may require re-evaluation of well locations as some attic oil may have not been drained in some Shannon blocks by present well locations. Therefore our study demonstrates how conventional 3D seismic data require additional seismic acquisition at smaller scales in order to image deformation in shallow reservoirs. Such imaging becomes critical in cases of shallow reservoirs where it is important to define potential problems associated with compartmentalization of primary production, hazard mitigation, enhanced oil recovery, or carbon sequestration.
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Sedimentary, structural, and provenance record of the Cianzo basin, Puna plateau-Eastern Cordillera boundary, NW ArgentinaSiks, Benjamin Charles 15 July 2011 (has links)
The fault-bounded Cianzo basin represents a Cenozoic intermontane depocenter between the Puna plateau and Eastern Cordillera of the central Andean fold-thrust belt in northern Argentina. New characterizations of fold-thrust structure, nonmarine sedimentation, and sediment provenance for the shortening-induced Cianzo basin at 23°S help constrain the origin, interconnectedness, and subsequent uplift and exhumation of the basin, which may serve as an analogue for other intermontane hinterland basins in the Andes. Structural mapping of the Cianzo basin reveals SW and NE-plunging synclines within the >6000 m-thick, upsection coarsening Cenozoic clastic succession in the shared footwall of the N-striking, E-directed Cianzo thrust fault and transverse, NE-striking Hornocal fault. Growth stratal relationships within upper Miocene levels of the succession indicate syncontractional sedimentation directly adjacent to the Hornocal fault.
Measured stratigraphic sections and clastic sedimentary lithofacies of Cenozoic basin-fill deposits show upsection changes from (1) a distal fluvial system recorded by
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fine-grained, paleosol-rich, heavily bioturbated sandstones and mudstones (Paleocene‒Eocene Santa Bárbara Subgroup, ~400 m), to (2) a braided fluvial system represented by cross-stratified sandstones and interbedded mudstones with 0.3 to 8 m upsection-fining sequences (Upper Eocene–Oligocene Casa Grande Formation, ~1400 m), to (3) a distributary fluvial system in the distal sectors of a distributary fluvial megafan represented by structureless sheetflood sandstones, stratified pebble conglomerates and sandstones, and interbedded overbank mudstones (Miocene Río Grande Formation, ~3300 m), to (4) a proximal alluvial fan system with thick conglomerates interbedded with thin discontinuous sandstone lenses (upper Miocene Pisungo Formation, ~1600 m).
New 40Ar/39Ar geochronological results for five interbedded volcanic tuffs indicate distributary fluvial deposition of the uppermost Río Grande Formation from 16.31 ± 0.6 Ma to 9.69 ± 0.05 Ma. Sandstone petrographic results show distinct upsection trends in lithic and feldspar content in the Casa Grande, Río Grande, and Pisungo formations, potentially distinguishing western magmatic arc (Western Cordillera) sediment sources from evolving eastern thrust-belt sources (Puna‒Eastern Cordillera). In addition to growth stratal relationships and 40Ar/39Ar constraints, conglomerate clast compositions reflect distinct lithologic differences, constraining the activation of the Cianzo thrust and coeval movement on the reactivated Hornocal fault. Finally, U-Pb geochronological analyses of sandstone detrital zircon populations in conjunction with paleocurrent data and depositional facies patterns help distinguish localized sources from more distal sources west of the basin, revealing a systematic eastward advance of Eocene to Miocene fold-thrust deformation in the central Andes of northern Argentina. / text
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Property inference decision-making and decision switching of undergraduate engineers : implications for ideational diversity & fluency through movements in a Cartesian concept design spaceShah, Raza January 2017 (has links)
Design fixation is a phenomenon experienced by professional designers and engineering design students that stifles creativity and innovation through discouraging ideational productivity, fluency and diversity. During the design idea and concept generation phase of the design process, a reliance on perceptual surface feature similarities between design artefacts increases the likelihood of design fixation leading to design duplication. Psychologists, educators and designers have become increasingly interested in creative idea generation processes that encourage innovation and entrepreneurial outcomes. However, there is a notable lack of collaborative research between psychology, education and engineering design particularly on inductive reasoning of undergraduate engineering students in higher education. The data gathered and analysed for this study provides an insight into property inference decision-making preferences and decision switching (SWITCH) patterns of engineering undergraduates under similarity-based inductive judgements [SIM] and category-based inductive judgements [CAT]. For this psychology experiment, property induction tasks were devised using abstract shapes in a triad configuration. Participants (N = 180), on an undergraduate engineering programme in London, observed a triad of shapes with a target shape more similar-looking to one of two given shapes. Factors manipulated for this experiment included category alignment, category group, property type and target shape. Despite the cognitive development and maturation stage of undergraduate engineers (adults) in higher education, this study identified similarity-based inductive judgements [SIM] to play a significant role during inductive reasoning relative to the strength of category-based inductive judgements [CAT]. In addition to revealing the property inference decision-making preferences of a sample of undergraduate engineers (N = 180), two types of switch classification and two types of non-switch classification (SWITCH) were found and named SIM_NCC, SIM-Salient, Reverse_CAT and CAT_Switching. These different classifications for property inference switching and non-switching presented a more complex pattern of decision-making driven by the relative strength between similarity-based inductive judgements [SIM] and category-based inductive judgements [CAT]. The conditions that encouraged CAT_Switching is of particular interest to design because it corresponds to inference decision switching that affirms the sharing of properties between dissimilar-looking shapes designated as category members, i.e., in a conflicting category alignment condition (CoC). For CAT_Switching, this study found a significant interaction between a particular set of conditions that significantly increased the likelihood of property inference decisions switching to affirm the sharing of properties between dissimilar-looking shapes. Stimuli conditions that combined a conflicting category alignment condition (where dissimilar-looking shapes belong to the same category) with category specificity, a causal property and a target shape with merged (or blended) perceptual surface features significantly increased the likelihood of a property inference decision switching. CAT_Switching has important implications for greater ideational productivity, fluency and diversity to discourage design fixation within the conceptual design space. CAT_Switching conditions could encourage more creative design transformations with alternative design functions through inductive inferences that generalise between dissimilar artefact designs. The findings from this study led to proposing a Cartesian view of the concept design space to represent the possibilities for greater movements through flexible and expanding category boundaries to encourage conceptual combinations, greater ideational fluency and greater ideational diversity within a configuration design space. This study has also created a platform for further research into property inference decision-making, ideational diversity and category boundary flexibility under stimuli conditions that encourage designers and design students to make inductive generalisations between dissimilar domains of knowledge through a greater emphasis on causal relations and semantic networks.
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