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Comparative Study of the Chemostratigraphic and Petrophysical characteristics of Wells A-Al, A-Ll, A-Ul and A-Il in the Orange Basin, South Atlantic Margin, Offshore South Africa.Bailey, Carlynne January 2009 (has links)
>Magister Scientiae - MSc / Many hydrocarbon reservoirs are situated in barren sequences that display poor stratigraphic control. Correlation between the wells can become extremely difficult and traditional correlation techniques can prove to be inadequate. Past studies have shown that trace and
major element concentrations can be used as a correlation tool. This practice of using geochemical fingerprints to characterize between wells is called Chemostratigraphic analysis. (Pearce et al, 1999) Chemostratigraphy has been recognized as a very important correlation technique as it can be used for rocks of any age, in any geological setting as well as sequences that are traditionally defined as barren. Chemostratigraphic analyses can be used as a means of getting rid of ambiguities within data produced by traditional correlation methods such as Biostratigraphy, Lithostratigraphy and Geophysical Logging. In areas where stratigraphic data is not available it can be used to construct correlation frameworks for the sequences found in the area. The motivation behind this study is that the research is not only worthy of academic investigation, but can also provide the industry with new insights into areas that were previously misunderstood because traditional correlation methods were not adequate. The study area, the Orange basin, is located offshore South Africa and is largely underexplored. The basin, that hosts two gas field namely the Ibhubesi and the Kudu gas fields, has large potential but in the past has not been given due attention with only 34 wells being drilled in the area. The Orange basin has recently been the topic of investigation because of the belief that it may be hosts to more hydrocarbons. This study will utilise Chemostratigraphy to attempt to provide geological information on this relatively under-explored basin. The aim of this research study is to produce a chemostratigraphic framework -scheme for the Orange Basin in order to facilitate reservoir scale interwell correlation. The Objectives of this research study will be to identify
chemostratigraphic units or indices, to prove the adequate use of chemostratigraphy as an independent correlation technique and to integrate the chemostratigraphy and petrophysical characteristics of the four wells to facilitate lithological identification. Element distribution Analysis was done on the data. This brought to the fore. the dominance of Si02 across the samples for the four wells. Ah03 concentrations were relatively high across the wells and were indicative of the clay rich nature of the samples. This also indicated that the samples were relatively immature. Principal Component Analysis (PCA) plots were constructed for the purpose of identifying diametrical relationships between the elements or element clusters. These diametric relationships were in turn used to calculate the geochemical indices. The relative positions of the elements on the PCA plot highlighted the presence of alternating units of sandstone, feldspathic sandstone, calcareous clays and non calcareous clays within the samples. The PCA plots displayed diametric relationships between Si02 and the carbonate mineral clusters, Si02 and the clay mineral clusters, Nd and V, Nb nad Ni, Zr and Co, Nb and Zn. Si02 and Co, Y and Pb, Zr and Sr, and lastly Nb and Ra / Downhole plots were constructed to illustrate recognizable trends in the PCA plot and to relate this to the occurrence of various lithologies in the wells. Based on the element distribution patterns, PCA plots and Major and Trace element downhole profiles geochemical indices were calculated. They are grouped into three clusters, ratios indicative of the presence of clean sandstones (High Si02/Ah03, Si02/Co, Zr/Co, Zr/Sr, YlPb and low Nd/V values); ratios indicative of the presence of clays (Low Si02/Ah03, Fe203/Ah03, Si02/Co, Zr/Co, YlPb and high Rb/Zn values); thirdly those indicative of the presence of feldspathic sandstones (High Na201K20) and lastly those indicative of the presence of carbonates (low Zr/Sr). Using the geochemical Indices six units were identified in Well A_AI, nine in A-II and 8 iin
Well A-UI and A-LI. Four units (A-D) were found to correlate across the wells. I Well log interpretation for the Wells A-AI, A-II, A-Lland A-UI started with a general overview of the log responses. The log responses for the four wells highlighted the presence of sandstones, argillaceous sandstones, shales and shale components. Geophysical units were identified using the logs responses. Six units were identified in Well A-AI, nine in Well A-II and eight in Wells A-LI and A-UI. These units coincide with the units identified using Chemostratigraphic analysis. Neutron - Density cross plots were constructed for each unit across the four wells. The plotting of the points on the Neutron - Density cross plots for the wells A-AI, A-II, A-LI and A-UI indicated the presence of sandstones, shales or greywackes and either limestones and dolomites but from the geochemistry it is known that neither limestone nor dolomite is present in the wells and it was thus inferred that the points
plotting between the limestone and dolomite lithology curves indicated the presence of calcareous shales. M-N plots were constructed for each unit. The patterns exhibited by the points on the M-N plots for the wells was indicative of the presence calcareous clays, sandstones, greywacke and shales. The Chemostratigraphic and Petrophysical results produced accurate and comparable results, however, the Chemostratigraphic analysis provided finer details regarding the lithology of the units. Based on the well log responses no distinction could be made between highly feldspathic sandstone, arkosic and argillaceous sandstone, while these distinctions were possible when analyzing the samples using Chemostratigraphy. The geochemistry was capable of providing signatures in areas where the wireline tools malfunctioned. The logs, on the other hand, sheds light on properties such as porosity and permeability of the rocks which cannot be obtained accurately from the geochemistry. When comparing the correlation capabilities of these two techniques, the one based on
geochemical signatures and the other based on the responses obtained from wireline tools, it is important to acknowledge that both these techniques has strengths and weaknesses. The best of both these techniques can only be fully utilised when either technique is used in
conjunction with other techniques. With respect to the Orange Basin, located offshore South Africa, it can be concluded that the dominant lithologies in the basin are sandstones, argillaceous sandstones, shales, feldspathic and arkosic sandstones and clays. In terms of petroleum prospectivity the sandstones in Wells A-AI, A-II, A-UI and A-LI could possibly be considered to be reservoirs and the shales could be considered to be seals or source rocks, depending on the organic matter content. On the down side, the sandstones display relatively poor permeabilities and the porosities are variable. The density logs indicate that the sandstones are highly compacted and that could be an indication of poor porosities but more research needs to be done. Another factor highlighted from the research is the presence of alternating lithologies. This means that the reservoirs are compartmentalised and that the area has a high degree of heterogeneity.
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The Landscape of Food and Beverage Advertising to Children and Adolescents on Canadian TelevisionPinto, Adena 05 November 2020 (has links)
Background: Canadian youth obesity, and comorbidities, have paralleled trends in consuming nutrient-poor foods marketed by the food industry. In Canada, food marketing is largely self-regulated by the food industry under the Canadian Children’s Food and Beverage Advertising Initiative (CAI).
Methods: Public television programming records benchmarked the volume of food advertising targeted to preschoolers, children, adolescents, and adults on Canadian television. Food advertising rates and frequencies were compared by age group, television station, month, food category, and company, using regression modelling, chi-square tests and principal component analysis.
Results: Food advertising rates significantly differed by all independent variables. Fast food companies dominated advertising during adolescent-programming while food and beverage manufacturers dominated advertising during programming to all other age groups. CAI signatories contributed more advertising during children’s programming than non-signatories.
Conclusion: Failings of self-regulation in limiting food advertising to Canadian youth demonstrate the need for statutory restrictions to rectify youth’s obesogenic media environments and their far-reaching health effects.
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Multi-risk modeling for improved agriculture decision-support: predicting crop yield variability and gaps due to climate variability, extreme events, and diseaseLu, Weixun 15 September 2020 (has links)
The agriculture sectors in Canada are highly vulnerable to a wide range of inter-related weather risks linked to seasonal climate variability (e.g., El Ni ̃no Southern Oscillation(ENSO)), short-term extreme weather events (e.g., heatwaves), and emergent disease(e.g., grape powdery mildew). All of these weather-related risks can cause severe crop losses to agricultural crop yield and crop quality as Canada grows a wide range of farm products, and the changing weather conditions mainly drive farming practices. This dissertation presents three machine learning-based statistical models to assess the weather risks on the Canadian agriculture regions and to provide reliable risk forecasting to improve the decision-making of Canadian agricultural producers in farming practices. The first study presents a multi-scale, cluster-based Principal Component Analysis(PCA) approach to assess the potential seasonal impacts of ENSO to spring wheat and barley on agricultural census regions across the Canada prairies areas. Model prediction skills for annual wheat and barley yield have examined in multi-scale from spatial cluster approaches. The ’best’ spatial models were used to define spatial patterns of ENSO forcing on wheat and barley yields. The model comparison of our spatial model to non-spatial models shows spatial clustering and ENSO forcing have increase model performance of prediction skills in forecasting future cereal crop production. The second study presents a copula-Bayesian network approach to assess the impact of extreme high-temperature events (heatwave events) on the developments of regional crops across the Canada agricultural regions at the eco-district-scale. Relevantweather variables and heatwave variables during heatwave periods have identified and used as input variables for model learning. Both a copula-Bayesian network and Gaussian-based network modeling approach is evaluated and inter-compared. The copula approach based on ’vine copulas’ generated the most accurate predictions of heatwave occurrence as a driver of crop heat stress. The last study presents a stochastic, hybrid-Bayesian machine-learning approach to explore the complex causal relationships between weather, pathogen, and host for grape powdery mildew in an experimental farm in Quebec, Canada. This study explores a high-performance network model for daily disease risk forecast by using estimated development factors of pathogen and host from recorded daily weather variables. A fungicide strategy for disease control has presented by using the model outputs and forecasted future weather variability. The dissertation findings are beneficial to Canada’s agricultural sector. The inter-related weather risks explored by the three separate studies in multi-scales provide a better understanding of the interactions between changing weather conditions, extreme weather, and crop production. The research showcases new insights, methods, and tools for minimizing risk in agricultural decision-making / Graduate / 2021-08-19
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A Logistic regression analysis model for predicting the success of computer networking projects in ZimbabweMasamha, Tavengwa 02 1900 (has links)
Information and communication technology (ICT) greatly influence today’s business processes
be it in public or private sectors. Everything that is done in business requires ICT in one way or
the other. Research in ICTs is therefore critical. So much research was and is still carried out in
projects that develop or enhance ICT but it is still apparent that the success rate of these projects
is still very low. The extensive coverage of ICTs implies that if the success rate is still that low,
many resources are being wasted in the failed projects; therefore, more research is needed to
improve the success rate. Previous research has focussed on factors which are critical for the
success of ICT projects, assuming that all ICT projects are the same. As a result, literature is full
of different suggestions and guidelines of the factors critical to ICT projects’ success. This
scenario brings challenges to project managers who end up using their own personal judgement
to select which factors to consider for any project at hand. The end result is the high failure rate
of ICT projects since there is a very high chance of applying the same critical success factors to
different types of ICT projects. This research answered the question: which factors are critical
to the success of computer networking projects in Zimbabwe and how these factors could be
used for building a model that determines in advance the success of such projects?
Literature reviewed indicated that most CSFs were not focused on specific types of ICT projects,
hence were generalised. No literature was found on ICT projects’ CSFs in Zimbabwe. More so,
no CSFs were found for computer networking projects as a specific instance of ICT projects. No
model existed that predicts computer networking projects’ success. This study addressed the
gaps by developing a CSF framework for ICT projects in Zimbabwe, determining CSFs for
computer networking projects in Zimbabwe and the development of a logistic regression analysis
model to predict computer networking projects’ success in Zimbabwe.
Data was collected in Zimbabwe using a unique three-staged process which comprise metasynthesis analysis, questionnaire and interviews. The study was motivated by the fact that most
available research focused on CSFs for general ICT projects and that no research was found on
CSFs influencing projects in computer networking. Meta-synthesis analysis was therefore
conducted on literature in order to identify CSFs as given in literature. The approach was
appropriate since the researcher had noticed that there were extensive ICT projects’ CSFs and
that no such research has been carried out in Zimbabwe.
These CSFs formed the basis for the determination (using a questionnaire) of ICT projects CSFs
for Zimbabwe in particular. Project practitioners’ viewpoints were sought through
questionnaires. Once CSFs for ICT projects in Zimbabwe were determined, they formed the
basis for the determination of unique critical success factors for computer networking projects
in Zimbabwe. Interviews were used to get further information that would have been left out by
questionnaires. The interview questions were set to clarify some unclear or conflicting responses
from the questionnaire and providing in-depth insights into the factors critical to computer
networking projects in Zimbabwe. The data i.e. critical success factors for computer networking
projects guided the development of the logistic regression analysis model for the prediction of
computer networking projects’ success in Zimbabwe.
Data analysis from the questionnaire was analysed using SPSS Version 23.0. Factor analysis and
principal component analysis were some of the techniques used in the analysis. Interview data
was analysed through NVivo Version 10.0. From the results it was deduced that factors critical
to ICT project management in Zimbabwe were closely related to those found in the literature.
The only apparent difference was that CSFs for ICT projects in Zimbabwe were more specific
thereby enhancing their applicability. Computer networking projects had fewer CSFs than
general ICT projects. In addition, CSFs for general ICT projects were different from those
critical to computer networking projects in Zimbabwe.
The development of a comprehensive set of general ICT projects’ CSFs was the first contribution
of this study. This was achieved through meta-synthesis analysis. The other contribution was the
development of a CSF framework for ICT projects specific to Zimbabwe and those specific to
computer networking projects in Zimbabwe. The major contribution was the development of the
logistic regression analysis model that predicts computer networking projects’ success in
Zimbabwe. These contributions will provide literature on ICT project management in Zimbabwe
which will subsequently assist ICT project managers to concentrate on specific factors. The
developed prediction model can be used by project managers to determine possible success or
failure of ICT projects; thereby possible reducing wastage of resource. / School of Computing
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Vyhledávání osob ve fotografii / Recognizing Faces within ImageSvoboda, Pavel January 2009 (has links)
The essence of face recognition within the image is generally computer vision, which provides methods and algorithms for the implementation. Some of them are described just in this work. Whole process is split in to three main phases. These are detection, aligning of detected faces and finally its recognition. Algorithms which are used to applied in given issue and which are still in progress from todays view are mentioned in every phase. Implementation is build up on three main algorithms, AdaBoost to obtain the classifier for detection, method of aligning face by principal features and method of Eigenfaces for recognizing. There are theoretically described except already mentioned algorithms neural networks for detection, ASM - Active Shape Models algorithm for aligning and AAM - Active Appearance Model for recognition. In the end there are tables of data retrieved by implemented system, which evaluated the main implementation.
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Data Mining the Effects of Storage Conditions, Testing Conditions, and Specimen Properties on Brain BiomechanicsCrawford, Folly Martha Dzan 10 August 2018 (has links)
Traumatic brain injury is highly prevalent in the United States yet there is little understanding of how the brain responds during injurious loading. A confounding problem is that because testing conditions vary between assessment methods, brain biomechanics cannot be fully understood. Data mining techniques were applied to discover how changes in testing conditions affect the mechanical response of the brain. Data were gathered from literature sources and self-organizing maps were used to conduct a sensitivity analysis to rank considered parameters by importance. Fuzzy C-means clustering was applied to find any data patterns. The rankings and clustering for each data set varied, indicating that the strain rate and type of deformation influence the role of these parameters. Multivariate linear regression was applied to develop a model which can predict the mechanical response from different experimental conditions. Prediction of response depended primarily on strain rate, frequency, brain matter composition, and anatomical region.
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The impact of Environmental, Social and Corporate Governance (ESG) practices on the financial performance of companies in emerging and frontier markets / Environmental, Social and Corporate Governance (ESG) påverkan på företags finansiella resultat i frontier och tillväxtmarknaderKulakova, Iuliana January 2018 (has links)
In this thesis, we explore the proprietary Environmental, Social and Corporate Governance (ESG) scores and analyze their impacts on firm valuation using the sample of 166 companies operating in 35 emerging and frontier markets. Three methods of ESG scores, Principal Component Analysis and regression analysis are used. The results indicate an economically significant relationship between the overall ESG measure and firm value mainly driven by the “Environmental” and “Capital allocation” sub-scores. An exploratory principal component analysis and an extensive list of firm characteristics is also employed in our regression analysis to address problems identified in previous studies - construct validity and endogeneity. The PCA revealed dominance of Environmental and Social components in the variance of the total ESG score. Finally, the strengths and weaknesses of proprietary ESG score and PCAderived index are recognized based on sector- and region level comparison and the opportunities to improve the ESG scorecard framework are identified. / In den uppsatsen, forskning går på Environmental, Social and Corporate Governance (ESG) poäng och analyserar deras påverkan på företagsvärdering genom att använda ett urval av 166 företag som verkar i 35 frontier och tillväxtmarknader. Tre metoder av ESG mätning, Principal Component Analysis och regressionsanalyser tillämpades. Resultat tyder på ett ekonomiskt signifikant förhållande mellan totala ESG mätning och företagsvärdering vilket drivs av miljö och kapitalallokering delpoäng. Principalkomponentanalys och en utförlig lista av företagsegenskaper tillämpades också i våra regressionsanalyser för att adressera problem identifierade i tidigare studier - begreppsvaliditet och endogenitetsproblem. PCA tydde på dominans av miljöoch sociala aspekter i varians av den totala ESG poängen. Avslutningsvis, styrkor och svagheter av ESG-poäng och PCA-härlett index baserat på bransch- samt regionaljämförelser och möjligheterna för förbättring av ESG-mätning ramverk identifierades.
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Using a social registry to assess household social vulnerability to natural hazards in MalawiSundqvist, Petter January 2023 (has links)
Social factors moderate the impacts of natural hazards, which means that households are affected differently when exposed to the same hazard. This differential impact of hazards can be explained by the concept of social vulnerability, which is commonly assessed to inform disaster preparedness and response action. Most of these assessments, however, focus their analyses on large administrative units and, consequently, neglect the heterogeneity of households within these units. This thesis leverages data from Malawi’s social registry (the UBR) to construct a Household Social Vulnerability Index for Nsanje – one of the most disaster-prone districts in Malawi. In Nsanje, geocoded socio-economic data was collected using a census-sweep approach with the goal of registering 100% of the district’s residents. From this dataset, indicators are deductively selected and analyzed using Principal Component Analysis to produce a social vulnerability score for each household. These index scores are mapped at a spatial resolution of 0,01°. By repurposing a social registry to inform a new set of actors, including humanitarian and disaster risk management practitioners, the thesis highlights the considerable scope for collaboration within the realm of data and information by actors and policy fields that traditionally largely have operated in isolation from one another.
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Risikoprämien von Unternehmensanleihen: Eine theoretische und empirische UntersuchungLu, Yun 10 July 2013 (has links)
Die Risikoprämie einer Unternehmensanleihe dient prinzipiell der wirtschaftlichen Kompensation für die Übernahme zusätzlicher Risiken gegenüber den Risiken der Benchmark. Allerdings findet sich in der bisher veröffentlichen Literatur eine Vielzahl von den praktischen Messkonzepten, die in vielen Fällen nicht fehlerfrei und problemlos zustande gekommen sind. Daher ist die präzise und quantitative Messung der Risikoprämien von Unternehmensanleihen eine betriebswirtschaftliche Notwendigkeit. In der vorliegenden Arbeit werden im Hinblick auf die Erreichbarkeit drei alternative Messkonzepte bezüglich der Risikoprämien von Unternehmensanleihen vorgestellt und miteinander verglichen.
Einige bisherige Studien sind der Auffassung, dass die Risikoprämien von Unternehmensanleihen zumeist von den Nicht-Kreditkomponenten beeinflusst werden. Um diese Marktanomalien zu erklären, verwenden die vorliegenden Untersuchungen das statistische lineare Faktor-Modell. In diesem Zusammenhang wird die Untersuchung von LITTERMAN/SCHEINKMAN (1991) auf die risikobehafteten Unternehmensanleihen übertragen. Im Kern steht die Frage, welche Risikoarten bzw. wie viele Einflussfaktoren wirken sich auf die Risikoprämien von Unternehmensanleihen in wieweit aus. Das Ziel ist ein sparsames lineares Faktor-Modell mit wirtschaftlicher Bedeutung aufzubauen. Somit leistet diese Dissertationsschrift einen wesentlichen Beitrag zur Gestaltung der Anleiheanalyse bzw. zur Portfolioverwaltung.
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Daily Profit Decomposition from Fluctuations in Interest Rates and Exchange Rates Extended with InventoryTörnquist, Jonathan, Zylfijaj, Rinor January 2022 (has links)
Multinational companies have consistently not been able to explain the impact currency and interest rates fluctuations have on their profits. To be able to account for these effects, thorough visibility is required. Epiroc Örebro is a global supplier of products and services within mining and infrastructure, with sales in more than 150 countries. The largest markets are Europe, North and South America and Asia. Naturally, with exposure to many different currencies and interest rates, it lies in the company’s interest to fully grasp and visualize the effects of these risk factors. The aim of this study is to provide and apply a performance attribution model to Epiroc Örebro, in order to fully grasp and visualize, how foreign exchange rates and interest rates affect the profits of the company’s operations on a daily basis. Main focus is on incorporating inventory into the performance attribution model. To fulfill the purpose of this thesis, literature studies on performance attribution models, foreign exchange risk, and interest rate risks were conducted. Epiroc Group and Epiroc Örebro were studied to get the full picture of their risk exposures. Consequently, a generic framework for performance attribution was extended, established and provided to their daily operations. The rigorous framework describes profit decomposition (ΔNPVt) with respect to risk factors. In summary, this mathematical model comprises of: a Taylor approximation for changes in price with several error terms, terms accounting for holding foreign currencies and assets, purchasing and sales of currencies and assets and lastly, a term accounting for currency fluctuations. See eq. (4.25) to eq. (4.35). The focus of this report is the addition of inventory into the existing performance attribution model. Inventory is valued to last purchase price and the value of inventory is only affected by price changes and exchange rate fluctuations. The main result of this study is that inventory can be incorporated into the performance attribution model. The model is comprehensive and fully explains the company’s NPV changes on a daily basis in detail. Furthermore, the conclusion is that the model can be extended to handle inventory, but several additions and adjustments are still to be added. Work regarding data extraction and cash flow prognosis will be required to scale the model and to enable real time use. / <p>Examensarbete i Finans från Civilingenjörsprogrammet i Industriell Ekonomi.</p>
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