Дисертації з теми "Oil spots"
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1
Oliveira, Leonardo Mendonça Tenório de Magalhães. "Modelagem e simulação da recuperação secundária em reservatórios de petróleo utilizando configuração Five-Spots." Universidade Federal de Alagoas, 2015. http://www.repositorio.ufal.br/handle/riufal/1215.
Повний текст джерелаАнотація:
The decline of oil reserves has been observed in recent years and generates interest in developing new technologies that can make the most of existing wells and reservoirs in order to increase oil recovery. For this purpose, methods and enhanced secondary recovery of oil are used, which consist of injecting fluids targeting a certain pressure increase in the tank or changes in physical properties of oil to a larger and more efficient production. The method of secondary recovery that stands out, and the most common is the water injection. This method has proved effective for recovery of heavy oil, though the challenge of the pre-salt environment has promoted further research aimed at removing light oils. This study, then, aims to make the fluid dynamics simulation of a reservoir of oil quadratic dimensions of 80.4 mx 80.4 mx 20 m with injection model five spots (five points) using as guns fluids primarily water and later natural gas and hot water, to observe the evolution of their volume fractions inside the shell, its oil recovery factor, recovery efficiency as a whole and a qualitative analysis of useful life of the producing wells. The developed model is based on two-phase oilwater model and the simulations were carried out in commercial fluid dynamic packet ICEM CFD and ANSYS CFX 13.0 respectively. Thus, a greater than 65% recovery factor for the process of injection water was observed and an overall efficiency of 38% recovery, allowing the case to the oil basins of the pre-salt. Other methods enabled to validate the model because the profiles and characteristics found are plausible and phenomenologically similar to those in the literature.O declínio das reservas petrolíferas vem sendo observado nos últimos anos e gera interesse no desenvolvimento de novas tecnologias capazes de aproveitar ao máximo os poços e reservatórios existentes de modo a elevar a recuperação de óleo. Para tanto, são utilizados métodos de recuperação secundária e avançada de petróleo, que consistem em se injetar determinados fluidos visando um aumento do diferencial de pressão no reservatório ou modificações nas propriedades físicas do óleo para uma produção maior e mais eficiente. O método de recuperação secundária que mais se destaca, e também o mais comum é a injeção de água. Tal método já se mostrou eficiente para recuperação de óleos pesados, entretanto o desafio do ambiente pré-sal tem promovido novas pesquisas voltadas para a remoção de óleos leves. O presente trabalho, então, tem como objetivo fazer a simulação fluidodinâmica de um reservatório de petróleo de dimensões quadráticas de 80,4 m x 80,4 m x 20 m com modelo de injeção five spots (cinco pontos) utilizando como fluidos injetores primeiramente a água e posteriormente o gás natural e água quente, para observar a evolução de suas frações volumétricas no interior do reservatório, seu fator de recuperação de óleo, a eficiência da recuperação como um todo e uma análise qualitativa de tempo de vida útil dos poços produtores. A modelagem desenvolvida baseou-se no modelo Água-Óleo bifásico e as simulações foram desenvolvidas nos pacotes fluidodinâmicos comerciais ICEM CFD e ANSYS CFX 13.0 respectivamente. Desse modo, foi constatado um fator de recuperação acima de 65% para o processo de injeção de água, bem como uma eficiência total de recuperação de 38%, viabilizando o processo para o óleo de bacias do pré-sal. Os outros métodos permitiram a validação da modelagem uma vez que os perfis e características encontrados foram fenomenologicamente plausíveis e similares àqueles da literatura.
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Pougy, Roberto. "Unconventional oil and natural gas supplies and the mitigation of climate change." Thesis, Paris, EHESS, 2017. http://www.theses.fr/2017EHES0075.
Повний текст джерелаАнотація:
Cette thèse en économie de l'énergie et de l'environnement étend le modèle de Hotelling du type exploration-extraction avec contraintes géologiques d’Okullo, Reynes et Hofkes (2015), afin de prendre en compte des trajectoires en forme de cloche pour l’ajout de réserves empiriquement observées par Laherrère (2003). Le modèle LOGIMA proposé (Images à Long terme sur le Pétrole et le Gaz) explique qu’elles sont la conséquence de « sweet spots » géologiques : des zones privilégiées où la concentration d’hydrocarbures est la plus élevée. Le modèle LOGIMA a été calibré sur une base de données issues couvrant les sept principaux bassins de pétrole et de gaz non-conventionnels du pays. Les résultats indiquent que la nécessité d’apprentissage par la pratique pour découvrir l’emplacement des sweet spots conduit à une mise en œuvre d’un effort d’exploration également en forme de cloche, ce qui permet de réduire le risque des activités d’exploration. Par conséquent, la réponse en termes des volumes offerts par les producteurs à des chocs sur les prix dévient fonction de l’ensemble des ressources mondiales antérieurement découvertes. Ensuite, nous appliquons le modèle LOGIMA pour étudier l’impact causé par l’offre de pétrole et de gaz naturel « non-conventionnels » aux États-Unis, sur les efforts mondiaux d’atténuation du changement climatique. Nous y parvenons en associant les scénarios à long-terme générés par LOGIMA avec le modèle d’évaluation intégrée, IMACLIM-R. Cette étude analyse comment des différentes cibles de prix de pétrole affecteraient son offre aux États-Unis. Nous estimons cette interaction au moyen de trois cadres de politiques en matière de climat : le cadre « business as usual » (BAU), les contributions décidées à l’échelle nationale (NDC) et les scénarios de 2°C (2DS). Les résultats de l’exercice indiquent que les approvisionnements non-conventionnels sont fortement susceptibles d’affecter les marchés énergétiques mondiaux, mais leur impact sur les émissions mondiales de gaz à effet de serre serait limité, car les différents effets déclenchés dans des différents secteurs viendraient les équilibrer approximativementThis thesis in energy and environmental economics extends the geological Hotelling-type extraction-exploration model from Okullo, Reynes and Hofkes (2015) in order to account for the bell-shaped reserve additions that were empirically observed by Laherrère (2003). The proposed model explains them as the result of geological “sweet spots”: premium areas within geological formations where the concentration of hydrocarbons is highest. The proposed theoretical formulation was programmed into the mathematical model LOGIMA – “Long-term Oil and Gas Images” – and calibrated on data covering the seven main unconventional oil and gas plays in the United States. Results indicate the need to learn the location of sweet spots through trial and error drillings leads to schedules of exploratory effort that allow the optimal “de-risking” of exploratory activities. As a result, the optimal response of producers to price shocks becomes contingent on the prevailing level of cumulative discoveries.We apply LOGIMA to investigate the impact, caused by the recent advent of large-scale supplies of unconventional oil and gas, in the United States, on the ongoing efforts to mitigate climate change. We do so by soft coupling long-term scenarios from LOGIMA with the integrated assessment model, IMACLIM-R, a recursive, computable general equilibrium model of integrated global energy, economy and environment systems. We analyze how different price targets, potentially pursued by the Organization of Petroleum Exporting Countries (OPEC), would affect supplies of unconventional oil and gas from the United States. We control this interplay under three climate policy frameworks: business as usual (BAU), nationally determined contributions (NDCs) and 2°C scenario (2DS). The results of the exercise show that, despite having a significant potential to affect global energy markets, unconventional oil and gas supplies would have a limited potential to affect global cumulative greenhouse gas emissions to 2040, as the different effects triggered in different sectors approximately balanced each other out
3
Melo, André de Souza. "Identificação de pontos quentes em transformadores de potência por meio de técnicas não invasivas." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-07112017-151817/.
Повний текст джерелаАнотація:
Esta pesquisa apresenta uma metodologia, baseada em duas técnicas não invasivas para identificação e diagnóstico de pontos quentes em transformadores de potência durante plena operação ou em fase de projeto. A primeira técnica é baseada na medição de radiação infravermelha, emitida pelo equipamento em funcionamento e registrada por meio de análise termográfica. A segunda técnica é possível a partir do conhecimento prévio das características construtivas do transformador, fazendo uso do Método dos Elementos Finitos (MEF). A segunda técnica pode ser validada a partir das medições realizadas utilizando a primeira técnica. A formação de gases no interior dos transformadores de potência, devido à elevação da temperatura do óleo isolante em função dos pontos quentes, é discutida em detalhes com base nas normas técnicas estabelecidas pelo IEEE e IEC. As técnicas e procedimentos abordados ao longo dessa pesquisa foram obtidos a partir de um transformador com potência nominal de 120 MVA e relação de tensão 13,8/230 kV, projetado para integrar uma fazenda eólica ao Sistema Interligado Nacional (SIN).This research presents a methodology based on two noninvasive techniques for identification and diagnostic of hot spots in power transformers during operation or project development. The first is based on measurements of infrared radiation from the equipment during operation and recording by thermography. The second technique is possible from the previous knowing of the constructive characteristics of the power transformer, by using the Finite Element Method (FEM). The second technique can be validated from measurements obtained using the first technique. The gas formation into the power transformers, because of the high temperatures in the insulating oil due to the hot spots, is discussed in details based on normative recommendations well established by the IEEE and IEC. All techniques and procedures to be approached in this research were obtained using a 120-MVA power transformer with voltage relationship of 13.8/230 kV that was projected to interconnect a wind farm to the Interconnected Brazilian System (Sistema Interligado Nacional - SIN).
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Лушнікова, Марія Віталіївна. "Прогнозування впливу техногенного забруднення на води Чорного моря". Master's thesis, КПІ ім. Ігоря Сікорського, 2020. https://ela.kpi.ua/handle/123456789/41751.
Повний текст джерелаАнотація:
Магістерська дисертація присвячена обґрунтуванню можливості створення нафтового бону який зможе ефективно фільтрувати нафтові плями в поверхневих водах акваторії Чорного моря. Проведено аналіз властивостей, характеристик і складу морської води. Запропоновано концепцію нафтового бону який буде складатись з синтетичних фільтрів, а також з природних матеріалів.
Встановлено залежності дії антропогенного впливу на води Чорного моря; залежності від дії синтетичних та природних матеріалів на фільтрацію нафтових плям на поверхні води.
Розроблено стартап-проект, основною ідеєю якого є виробництво нафтового бону який завдяки поеднанню двох матеріалів зможе ефективно очищувати воду. Розраховано, що для запуску проекту необхідно 697765 грн інвестицій.The master's dissertation is assigned to the structure of the mobility of the stem of the naphtha bon, which can effectively filter naphtha in the surface waters of the Black Sea. The analysis of authorities, characteristics and warehouse of sea water was carried out. The concept of a naphtha boom, which will be composed of synthetic filters, as well as natural materials, is proponated. Deposits of anthropogenic plants were established in the waters of the Black Sea; deposits of synthetic and natural materials on the filtration of naphtha beaches on the water surface. A start-up project has been broken up, the main idea of which is the production of a naphtha boom, which means that two materials can be eaten efficiently. Rozrakhovano, scho for the launch of the project needs: 697765 UAH investment.
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Lock, Lillie Marlén. "Future fuel for worldwide tankershipping in spot market." Thesis, KTH, Marina system, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-121509.
Повний текст джерелаАнотація:
Ship exhausts contain high levels of sulphur oxides, nitrogen oxides, carbon dioxide and particles dueto the heavy fuel oil, HFO, used for combustion and the combustion characteristics of the engine.As a result of upcoming stricter regulations for shipping pollution, as well as growing attentionto greenhouse gas emissions, air pollution and uncertainty of future petroleum oil supply, a shifttowards a cleaner burning fuel is needed.This work explores potential alternative fuels, both conventional and unconventional, and abatementtechnologies, to be used by tankers in the worldwide spot market to comply with upcomingenvironmental regulations in the near and coming future. As a reference the product tanker M/TGotland Marieann is used and recommendations for which fuel that shall be used by the referenceship in 2015 and 2020 are presented.The environmental assessment and evaluation of the fuels are done from a life cycle perspective usingresults from Life Cycle Assessment, LCA, studies.This study illustrates that, of the various alternatives, methanol appears to be the best candidatefor long-term, widespread replacement of petroleum-based fuels within tanker shipping. It does notemit any sulphur oxides nor particles and the nitrogen oxides are shown to be lower than those ofmarine gas oil, MGO. The global warming potential of the natural gas produced methanol is notlower than that of MGO, but when gradually switching to bio-methanol the greenhouse gas emissionsare decreasing and with methanol the vision of a carbon free society can be reached.For 2015 a switch towards methanol is not seen as realistic. Further research and establishment ofregulations and distribution systems are needed, however there are indications that a shift will bepossible sometime between 2015 and 2020. For 2015 a shift towards MGO is suggested as it involveslow investment costs and there is no need for infrastructure changes. As MGO is more expensivethan methanol, a shift is preferable as soon as the market, technology and infrastructure are ready.
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Okogu, B. E. "The spot market, inventory management and crude oil price behaviour : 1975-1983." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234327.
Повний текст джерела
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Nilsson, Mattias. "Is The Oil Market Efficient? : A Cointegration Study of Spot and Futures Prices." Thesis, Mid Sweden University, Department of Social Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-527.
Повний текст джерелаАнотація:
The oil market is arguably the most influential commodity market in the world, in that it has an effect on all economic variables in one way or another. Due to oil’s central role in the world economy, it is of the utmost importance that all parts of society strive to increase the understanding of how the market works. This study has analysed the efficiency of the oil market in the period 1986 to 2008, with the efficient market hypothesis as the theoretical framework. Data on the prices of spot and futures contracts on crude and heating oil has been collected from the New York Mercantile Exchange, and tested for cointegration, with the underlying assumption being that cointegration is a sign of weak form efficiency. The results implies that the spot and futures prices have not been cointegrated during the studied period, and thus we conclude that the oil market has not behaved in accordance with the weak form of the efficient market hypothesis.
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Milligan, Gemma. "Fitness standards for the Maritime and Coastguard Agency and the oil and gas industry." Thesis, University of Portsmouth, 2013. https://researchportal.port.ac.uk/portal/en/theses/fitness-standards-for-the-maritime-and-coastguard-agency-and-the-oil-and-gas-industry(7c9bd4fa-fdd5-4e6f-9299-6769189decd9).html.
Повний текст джерелаАнотація:
The studies presented in this thesis were conducted to develop two minimum fitness standards, one for the Maritime and Coastguard Agency and the second for the Oil and Gas Industry. This provided the opportunity to compare across the essential tasks and resultant standards. The following stages were used for both the Maritime and Coastguard Agency and Oil and Gas Industry: a. Review the tasks requiring a significant physical fitness component (Task Analysis); b. Determine the importance of the physically demanding tasks and identify those which are critical for success and safe work (Task Assessment); c. Establish the method of best practice (Technique) for undertaking the essential tasks; d. Establish and agree the minimum performance standard for the essential tasks (Task Performance) when performed using the method of best practice; e. Assess the physical and physiological demands of these tasks (Task Quantification); f. Design and validate a simple-to-administer minimum fitness standard. The essential tasks and fitness requirements of the Maritime and Coastguard Agency fell into three groups, these were: Group 1 (All Operations): achieve a maximum aerobic score of at least 31 mL.kg-¹.min-¹ based on the aerobic demand of 21.8 mL.kg-¹.min-¹ required to carry a stretcher at the head-end 200 m at a speed of 3.2 km.h-¹; continuously lift a 3 kg sledge hammer 10 times above shoulder height, based on hammering a stake into the ground; pull a rope, with a resistance of 35 kg, and maintain this load for 15 s based on manning a main rescue-line; carry a 19 kg hand-held load 200 m in 3 min 45 s allow 3 min 45 s rest, then carry a 25.5 kg hand held load, 200 m in 3 min 45 s, based on the ability to carry a stretcher (89 kg) as part of a four person team. Group 2 (Rope Technicians) should complete all the tasks as Group 1, plus pass all the technical competencies currently in place for Rope Technicians. Group 3 (Mud Technicians) as Group 1, plus achieve a predicted maximum aerobic score of at least 39 mL.kg- ¹.min-¹ based on the aerobic demand of 27.4 mL.kg-¹.min-¹ required to pull a stretcher across the mud at 0.8 km.h-¹, (this equates to covering 200 m in 15 minutes), prior to performing a simulated mud rescue. The essential tasks and the minimum fitness requirements of the Oil and Gas Industry were: Stair and Ladder-Climbing, achieve a predicted maximum aerobic score of at least 31 mL.kg-¹.min-¹ based on the aerobic demand of 23.4 mL.kg- ¹.min-¹ required to climb a flight of stairs at a rate of 80 steps.min-¹ and 23.6 mL.kg- ¹.min-¹ to climb a ladder at 24 rungs.min-¹; Manual Handling, based on the requirement to climb a flight of stairs at a rate of 80 steps.min-¹ for a minute carrying a load of 10 kg, 20 kg or 25 kg; Valve Turning, based on the requirement to continuously turn a medium size valve (25.4 cm diameter) set at a torque of 8.3 N.m, for 5 min; Emergency Response Team, achieve a predicted maximum aerobic score of at least 41 mL.kg-¹.min ¹, based on the aerobic demand of 30.7 mL.kg-¹.min-¹ required to pull a trailer/foam monitor at a speed of 5 km.h-¹. If trailer/foam monitors are not used achieve a predicted maximum aerobic score of at least 39 mL.kg-¹.min-¹ based on the aerobic demand of 28.9 mL.kg-¹.min-¹ required to climb a ladder at 34.5 rungs.min-¹. Stretcher carry 89 kg either in a two or four person lift (dependant on the facility), rope haul the heaviest anticipated load (10 kg first aid kit) up 10 m gantry, roll out a 23 m fire hose. There were no time constraints recommended for hauling kit and rolling out a hose. For those essential tasks that could not be assessed by a direct task measurement or a direct task simulation, a Predictive selection test was recommended and validated. Prediction intervals were used to take into account the inherent error between the predictive tests and the direct measurements, to determine “Pass”, “Borderline” and “Fail” categories. As a result of this work a modular approach was adopted in which individuals only undertake those test applicable to their job, with a combination of direct task measurements, direct task simulations, and Predictive selection tests recommended. It is suggested that, where possible, the use of a direct task measurement or simulation should either be progressive e.g. stretcher-carrying, or performed after a Predictive selection test, in order to reduce the risk of injury when the individuals proceed to undertake the direct task measurement or simulation e.g. manual handling. This approach has meant that consideration is given to the health and safety of the individuals undertaking the fitness standard whilst maintaining a high level of face validity.
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Ramberg, David J. (David John). "The relationship between crude oil and natural gas spot prices and its stability over time." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59566.
Повний текст джерелаАнотація:
Thesis (S.M. in Technology and Policy)--Massachusetts Institute of Technology, Engineering Systems Division, 2010.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student submitted PDF version of thesis.
Includes bibliographical references (p. 122-126).
The historical basis for a link between crude oil and natural gas prices was examined to determine whether one has existed in the past and exists in the present. Physical bases for a price relationship are examined. An econometric modeling exercise seeks to establish whether a stable price relationship exists and to define it through the use of a vector error correction model. The model identifies strong evidence of cointegration between the crude oil and natural gas spot price series in the United States. It conditions the predicted natural gas price volatility through exogenous variables related to weather and supply. Once identified, the relationship is clarified more efficiently through the implementation of a conditional error correction model. The model is then utilized to simulate the effects of weather shocks, seasonality, supply deviations and hurricane activity on the cointegrating relationship between crude oil and natural gas. Finally, an analysis is conducted to test whether the relationship shifts over time to new equilibria. The results of the series of exercises suggest that crude oil and natural gas prices have moved together historically and statistical analysis supports the assumption that the two price series continued to be cointegrated through the end of 2008. The analysis presents evidence that the relationship shifts over time to new equilibria, and the data suggest that these new eqilibria are likewise stable.
by David J. Ramberg.
S.M.in Technology and Policy
10
Karaca, Haldun. "Prediction Of Hot-spot And Top-oil Temperatures Of Power Transformers According To Ieee Standards C57.110-1998 And C57.91-1995." Master's thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12609140/index.pdf.
Повний текст джерелаАнотація:
In this thesis, the effects of Harmonics on the Top Oil and Hot Spot Temperatures of Power Transformers used in Turkish Electricity Transmission System have been investigated. Due to the solid state equipment, the harmonic levels increase. This effect raises the losses and temperatures in the transformer windings. None of the power transformers currently used in Turkey has measuring equipment suitable for measuring the Hot-Spot temperatures. In this study, a computer program is written in LABVIEW which measures the harmonics and calculates the temperatures in accordance with the methods recommended in IEEE Standards C57.110-1998 and C57.91-1995. Also for sample transformers the work has been verified by measuring the Top-Oil temperatures of the transformers and then comparing with the calculated results.
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Pradhan, Manoj Kumar. "Conformal Thermal Models for Optimal Loading and Elapsed Life Estimation of Power Transformers." Thesis, Indian Institute of Science, 2004. http://hdl.handle.net/2005/97.
Повний текст джерелаАнотація:
Power and Generator Transformers are important and expensive elements of a power system. Inadvertent failure of Power Transformers would cause long interruption in power supply with consequent loss of reliability and revenue to the supply utilities. The mineral oil impregnated paper, OIP, is an insulation of choice in large power transformers in view of its excellent dielectric and other properties, besides being relatively inexpensive.
During the normal working regime of the transformer, the insulation thereof is subjected to various stresses, the more important among them are, electrical, thermal, mechanical and chemical. Each of these stresses, appearing singly, or in combination, would lead to a time variant deterioration in the properties of insulation, called Ageing.
This normal and inevitable process of degradation in the several essential properties of the insulation is irreversible, is a non-Markov physico-chemical reaction kinetic process. The speed or the rapidity of insulation deterioration is a very strong function of the magnitude of the stresses and the duration over which they acted. This is further compounded, if the stresses are in synergy. During the processes of ageing, some, or all the vital properties undergo subtle changes, more often, not in step with the duration of time over which the damage has been accumulated. Often, these changes are non monotonic, thus presenting a random or a chaotic picture and understanding the processes leading to eventual failure becomes difficult. But, there is some order in this chaos, in that, the time average of the changes over short intervals of time, seems to indicate some degree of predictability.
The status of insulation at any given point in time is assessed by measuring such of those properties as are sensitive to the amount of ageing and comparing it with earlier measurements. This procedure, called the Diagnostic or nondestructive Testing, has been in vogue for some time now.
Of the many parameters used as sensitive indices of the dynamics of insulation degradation, temporal changes in temperatures at different locations in the body of the transformer, more precisely, the winding hot spots (HST) and top oil temperature (TOT) are believed to give a fairly accurate indication of the rate of degradation. Further, an accurate estimation of the temperatures would enable to determine the loading limit (loadability) of power transformer.
To estimate the temperature rise reasonably accurately, one has to resort to classical mathematical techniques involving formulation and solution of boundary value problem of heat conduction under carefully prescribed boundary conditions. Several complications are encountered in the development of the governing equations for the emergent heat transfer problems. The more important among them are, the inhomogeneous composition of the insulation structure and of the conductor, divergent flow patterns of the oil phase and inordinately varying thermal properties of conductor and insulation.
Validation and reconfirmation of the findings of the thermal models can be made using state of the art methods, such as, Artificial Intelligence (AI) techniques, Artificial Neural Network (ANN) and Genetic Algorithm (GA).
Over the years, different criteria have been prescribed for the prediction of terminal or end of life (EOL) of equipment from the standpoint of its insulation. But, thus far, no straightforward and unequivocal criterion is forth coming. Calculation of elapsed life in line with the existing methodology, given by IEEE, IEC, introduces unacceptable degrees of uncertainty. It is needless to say that, any conformal procedure proposed in the accurate prediction of EOL, has to be based on a technically feasible and economically viable consideration. A systematic study for understanding the dynamical nature of ageing in transformers in actual service is precluded for reasons very well known. Laboratory experiments on prototypes or pro-rated units fabricated based on similarity studies, are performed under controlled conditions and at accelerated stress levels to reduce experimental time. The results thereof can then be judiciously extrapolated to normal operating conditions and for full size equipment.
The terms of reference of the present work are as follows;
1. Computation of TOT and HST
Theoretical model based on Boundary Value Problem of Heat Conduction
Application of AI Techniques
2. Experimental Investigation for estimating the Elapsed Life of transformers
Based on the experimental investigation a semi-empirical expression has been developed to estimate the loss of life of power and station transformer by analyzing gas content and furfural dissolved in oil without performing off-line and destructive tests.
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Roubal, Christophe. "Tavelures du pommier et de l'olivier : réalisation de modèles épidémiologiques par des méthodes exploitant des observations biologiques acquises au verger." Thesis, Avignon, 2017. http://www.theses.fr/2017AVIG0694/document.
Повний текст джерелаАнотація:
La modélisation de la dynamique épidémiologique des ascomycètes parasites des arbres fruitiers présente deux aspects très importants : l’évaluation de la quantité d'inoculum et de son évolution, et l’identification des évènements climatiques donnant lieu à une contamination. Le travail présenté aborde ces deux aspects au travers de deux exemples : la tavelure du pommier, et la maladie de l’œil de paon de l’olivier, parasites majeurs pour les filières concernées.L’acquisition des connaissances sur la biologie des deux maladies a été abordée uniquement sur la base de données acquises sur le terrain, ce qui est original car généralement les modèles ont été réalisés sur la base de connaissances établies en conditions contrôlées.Dans le cas de Venturia inaequalis, agent de la tavelure du pommier, la vitesse de développement journalier de l’inoculum a été établie par optimisation numérique, sur la base d’observations réalisées en Provence. Un modèle de dynamique de projection des ascospores incluant la suspension de l’évolution de l’inoculum primaire lors des périodes sèches a été réalisé puis validé sur un jeu de données indépendantes. La transposabilité du modèle a été ensuite étudiée pour une autre région (Aquitaine). Dans le cas de Fusicladium oleagineum, agent de la maladie de l’oeil de paon, les conditions de contamination ont été établies en fonction de la température et de l’hygrométrie, d’une part par la réalisation d’un abaque sur la base de points sélectionnés par dires d’expert, et d’autre part de façon automatique à l’aide d’un système par apprentissage (réseau de neurones). Un modèle, liant la température moyenne après la contamination à l’apparition des symptômes a été ensuite réaliséApple scab, caused by Venturia inaequalis, and peacoq leaf spot, cause by Fusicladiumoleagineum, are key diseases respectively for apple and olive growers. These disease usuallyrequire a large number of treatments. Adequate protection need a good evaluation ofquantitative disponibility of inoculum, and estimation of infection conditions.In this thesis, these two problems were studied using only field data. This is an originalaprroach to obtain knowledge about biology of fungi : most previous works were realised byregression of laboratory data obtained under controled conditions.In the case of Venturia inaequalis, primary inoculum consists of pseudothecia present in leaflitter. Treatments agains ascospore release period is the cornerstone of the strategy againstapple scab. However, the existing forecasting models are not reliable, and are all based ondegree-day time scale, proposed in 1982.Here, using a corpus of data acquired between 1996 and 2013, including observations ofascospore release and weather data, we assessed the daily rate of development of primaryinoculum by fitting generic new time scale functions. Further improvements were then studiedto take into account elements reported in litterature about the incidence of rain or wetness.Different methods were tested and adapted for the parameterisation of models by numericaloptimisation. Some forcasting models were proposed and adapted to the area where the studywas conducted, with parameters including rain and temperature. The validity was tested, andfurther developements of the forecasting tool was then proposed.In the case of Fusicladium oleagineum, a field-operational model predicting disease outbreakswas established as a function of temperature and relative humidity. First with the help ofpoints selected by experts, Secondly automaticaly using a neural network. A model defininglatent period as a function of average temperature after contamination was then realised
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Wang, Yao-Chin, and 王瑤琴. "The Dynamic Relationship among the Returns of International Crude Oil Spots -Using BEKK Multivariate GARCH Model." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/76nr75.
Повний текст джерелаАнотація:
碩士淡江大學
財務金融學系碩士在職專班
95
In this study, we apply the BEKK multivariate GARCH model, proposed by Engle and Kroner (1995), to analyze the relationships among the Brent crude oil return, the West Texas Intermediate crude oil return and the Dubai crude oil return. The sample period is divided into before uptrend and during uptrend two sub-periods. First, we deeply analyze dynamic relationships of three crude oil returns. Moreover, we use impulse response function to analyze the dynamic effect when one variable’s innovation occurred. The results show that the return of Brent and WTI affect each other strongly especially during uptrend period. For spillover effect, the unexpected impulse occur positive effect to other markets before uptrend period. However, the result is inconsistent during up-trend period. Finally, for impulse response function, we found the impulse reflection period obviously extended when facing itself or other markets, during uptrend period. Thus, we prove that the dynamic relationships and impulse response function of three returns between oil price uptrend and during uptrend is obviously different.
14
Yao-Chin and 王瑤琴. "The Dynamic Relationship among the Returns of International Crude Oil Spots -Using BEKK Multivariate GARCH Model." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/n4rjvc.
Повний текст джерелаАнотація:
碩士淡江大學
財務金融學系碩士在職專班
95
In this study, we apply the BEKK multivariate GARCH model, proposed by Engle and Kroner (1995), to analyze the relationships among the Brent crude oil return, the West Texas Intermediate crude oil return and the Dubai crude oil return. The sample period is divided into before uptrend and during uptrend two sub-periods. First, we deeply analyze dynamic relationships of three crude oil returns. Moreover, we use impulse response function to analyze the dynamic effect when one variable’s innovation occurred. The results show that the return of Brent and WTI affect each other strongly especially during uptrend period. For spillover effect, the unexpected impulse occur positive effect to other markets before uptrend period. However, the result is inconsistent during up-trend period. Finally, for impulse response function, we found the impulse reflection period obviously extended when facing itself or other markets, during uptrend period. Thus, we prove that the dynamic relationships and impulse response function of three returns between oil price uptrend and during uptrend is obviously different.
15
CHEN, LI-SHIANG, and 陳立翔. "A Study on the Relationships between Return and Volatility in Crude Oil Futures Market and Spots Market." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/19696841569509770643.
Повний текст джерелаАнотація:
碩士高苑科技大學
經營管理研究所
97
This study looks to explore the link between two variables in order to understand the fluctuation in prices in the crude oil market. It analyzes both the WTI stock prices and Crude oil light futures prices traded on NYMEX, and whether there is a close interaction and mutual relationship between them, or whether they demonstrate price separation characteristics; using the single variable analysis model will not effectively offer us a joint explanation. What is needed is the multiple variable model, which takes into consideration variables from both sides in an attempt to derive at a most appropriate and complete analysis of the dynamic interaction between them. It is hoped that the findings can be useful as an important point of reference for both the investors and industries in deciding investment portfolio. The research subjects used in this study are the United States West Texas Intermediate Crude Oil (WTI) stock prices and Texas light crude oil (Crude oil futures right) futures prices, and the time of this study is the daily closing information between January 2nd 1986 and November 25th 2008. Using the BEKK-GARCH(1,1) model, this article looks to explore the effects of return fluctuations in both the crude oil futures and the stock market. The study showed that there is a “price-connectedness and fluctuation pass-on effect” and a close interaction between US WTI crude oil futures prices and Texas light crude oil futures prices. The study revealed the following results: (1) there is a cause and effect relationship between crude oil futures and stock market. This conclusion is in line with the theory that futures have a price-finding function. (2) Investors trading in crude oil stock market are strongly influenced by previous crude oil futures market prices, and this shows that investors have a habit to study past transactions on crude oil futures before transacting on crude oil stock market. (3) Crude oil futures is often greater than the spillover effects of crude oil stock market fluctuations. (4) As the daily returns of previous issue crude oil futures or stock market began to wane and prices showed a downward trend, this gives an indication that investors will soon be buying in very quickly for profits or for great deals, and as a result causing a short supply in Texas light crude oil futures and WTI crude oil stock market.
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Li, Shih-chi, and 李世琪. "An Empirical Study of the Impact of the U.S. Energy Independence and Security Act of 2007 on the Prices Interaction among Crude Oil Spots and Bio-fuel Crops Spots." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/93794261262972867918.
Повний текст джерелаАнотація:
碩士東海大學
管理碩士在職專班
96
With the weekly-data time series of crude oil spot price, and the spot prices of three kinds of bio-fuel crops, i.e. soybean, corn and wheat, as the endogenous variables, and the weekly-data time series of the U.S. dollar index as the exogenous variable, this thesis aims to empirically investigate the impact of the U.S. Energy Independence and Security Act of 2007 on the prices interaction among crude oil spots and the above three bio-fuel crops spots. All the data collected for investigation are from 01/03/2003 to 14/03/2008. The research results show that, before 2006, the crude oil spot price and the above three bio-fuel crops spot prices were not cointegrated; however, after 2006, they were cointegrated, meaning there was a long run equilibrium relationship among them. The author thinks it was the U.S. Energy Independence and Security Act of 2007 and people’s psychology of expecting the enforcement of that policy since 2006 that caused this long run equilibrium state among the above variables. By further using the Vector Error Correction Model(VECM) to analyze the short run interaction among the above variables, it is shown that, corn spot price will return to the long run equilibrium state promptly after a short run deviation from the long run equilibrium state, hinting the liquidity of corn spots seems slower than that of corn futures; while in the prices interaction among crude oil spots and bio-fuel crops spots, crude oil spot price apparently had a strong influence on the spot prices of soybean and corn, and a two-way effect between crude oil spot price and corn spot price was found; however, no evident prices interaction was found between wheat spots and crude oil spots. Interaction among the prices of soybean, corn, and wheat, was also found, whether the interaction was caused by the direct or cross effect of price variation of the previous periods of respective variables; it was found that soybean spot price has the highest effect, and next comes with wheat. In addition, the continued depreciation of U.S. dollar during the period investigated was the main reason that caused the uprising of soybean and wheat spot prices. The analysis results of impulse response functions show that after 2006, the impulse responses of the price rates of return of all the above variables descended quickly to zero within 2 to 3 periods(weeks), indicating a strong relationship of short run error correction among the price rates of return of all the above variables. Lastly, the analysis results of the forecasted variance decomposition show that after 2006, the price rates of return of soybean spots and crude oil spots had more power in self explanation, with a level of more than 90%; the exogeneity of the price rates of return of corn spots and wheat spots was relatively weaker; the price rate of return of crude oil spots was accounted by the price rates of return of soybean spots and corn spots to the extent with 1.62% and 4.28% respectively, indicating that the effect of adopting corn-based bio-fuel as an alternative of crude oil was higher than that of soybean-based bio-fuel.
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Huang, Min-Hua, and 黃敏華. "The Linkages among Oil Spot, Oil Future, and Stock Markets." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/72188065521882472425.
Повний текст джерелаАнотація:
碩士中原大學
國際貿易研究所
94
This study aims at finding out the linkages among oil spot, oil future, and stock markets. By using international oil spot, oil future, and market indices in different countries, and categorizing them into 3 separate models, the effects of price shocks originating from oil spot and oil futures markets on stock indices in different countries are examined. We use unite root test, cointegration test, VAR and VEC models to figure out the long- and short-term relationships among the variables of interest. The data are collected from July 21, 1999 to June 26, 2006. Our empirical results indicate that 1. According to unit root test, after first differences, the original variable series all became stationary ones. And the results of cointegration test show that there is a long-term equilibrium relationship among oil spot, oil future, and market indices in each country. Also, the long-term equilibrium relationship exists among oil spot, oil future, market indices, and market index futures in each country. 2. VEC model results indicate that short-term oil spot is overvalued and adjust to next session with a particular speed when oil spot is far away from long-term equilibrium. 3. According to the variance decomposition of forecast errors, in the model of market index and oil spot and futures, the most important factor is oil spot no matter there is a spontaneous interference of oil spot or oil futures. Up to 98% of market index can be explained by its spontaneous interference. In USA and Taiwan, no matter spontaneous interference exists in oil spot or oil futures, the most important factor is still the oil spot. However, in Japan, the essential factor is oil futures instead. 4. After observing the impact reactions among each variable when the spontaneous interference happens in oil futures, oil spot is influenced the most by oil future. Considering the market index futures while the spontaneous interference happens in market index, the impact of market index futures is affected most by the market index.
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Tzou, Yi-Pin, and 鄒易凭. "Impacts of Oil Spot on the Co-movements across Oil Sensitive Industries." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/27313262826626323668.
Повний текст джерелаАнотація:
碩士淡江大學
財務金融學系碩士班
95
The change of crude oil price has a great influence on all economies, also exert an influence on other economies. Other relevant industries, high oil sensitive transportation industries, and oil intensive manufacturing industries have more direct influences. In view of this, the fluctuation of crude oil spot price correlates with high oil sensitive industries, and integrates between high returns and low returns. In the oil price, the dynamic relation of sensitive industries. Empirical results show that the lower oil price has positive effects in prospecting industries. Airlines and transportation industries must constantly purchase oil for a long period of time in order to keep operating, hence they have already avoid the oil price volatility risk. High oil sensitive industries stock indices returns jump intensity and frequency are all time variant. In addition, applying impulse response function to examine high and low returns of oil spots, which indicates that Nasdaq transportation stock indices has an independent character. For this reason, oil sensitive industries and investors must consider oil price variation to relevant industries effect, in order to offer policymakers to make appropriate decisions.
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Wang, Yi-Wen, and 王怡文. "The Hedging Strategy of Crude Oil Spot." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/rch4h3.
Повний текст джерелаАнотація:
碩士淡江大學
財務金融學系碩士班
95
Because of the economic recession always comes with continuous rise in price of oil. Consequently, hedging of oil price becomes a crucial important issue. Although the GARCH model can capture the volatility of price and ARJI model can capture the jump component of price, it is not good enough to correct fat-tailed property of returns distribution. Base on the point, this paper employs the GARCH model, ARJI model and GARCH-NoVaS model that accommodate the heavy-tailed returns innovation proposed by Politis (2004) to further examine the hedge performance for crude oil commodity markets (WTI and Brent Crude Oil) under alternative hedging periods during the Gulf War in 1990. The empirical results show that hedging during high volatility period can reduce variance about 70%~80%. The ARJI model generates superior hedge performance to GARCH model. Moreover, the assumption of GARCH residual in heavy-tail distribution is more appropriate than normal distribution, so that models which accommodate with heavy-tail returns innovation have better hedge performance than traditional return specification. Overall, this paper suggests using the ARJI model to enhance the hedge performance for investors in WTI crude oil markets, while using the GARCH-NoVaS model to abate investment risk for them in Brent crude oil markets.
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Chen, Kung-Chang, and 陳恭誠. "how to make the glaze of oil-spot tenmuku." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/7ect7x.
Повний текст джерела
21
Chan, Shih Wei, and 詹世偉. "Detection of Oil Reservoir Bright Spot Using Back-propagation." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/838vz7.
Повний текст джерелаАнотація:
碩士國立交通大學
土木工程系所
96
he complexity of two-dimensional seismic data often leads to mistakes in discriminating oil reservoir. However, mis-drilling caused by these mistakes brings about thirty million loss in cost each time. Seismic data interpreters do recognition by rules and experiences. If we can use neural network in place of rules and experiences, then we can get rid of some chances of seismic data interpreters’ emotional discrimination or mislook. The past oil reservoir bright spot detections still can't be applied to practice for two reasons. First, target seismic data in past research to be detected is in perfect condition. Interpreters seldom deal with these kinds of seismic data in reality. There is a big difference between seismic data in perfect condition and seismic data in practice. Second, the seismic attributes that past research used differs from that interpreters used in oil companies. The primary goal of this research is to apply back-propagation neural network to pattern recognition of oil reservoir bright spot. By interviewing with Seismic data interpreters in the oil company, we propose five seismic attributes in common use including seismic signal, evelope, instantaneous frequency, instantaneous phase and inversion impedance. After five seismic attributes of feature extraction, we do pre-processing on extracted features including transformating .segy file into .mat file, elimination of blunder, elimination of outlier, normalization and building feature set matrixes. Then, we import feature set into neural network and train matrix by matrix. By tuning any possible neural network layer, hidden layer node, training function(Levenberg-Marquardt, Conjugate Gradient), we have summed up to 12480 times of neural network training. Finally, we propose a method of optimized-recognition rated oil reservoir bright spot detection.
22
Wang, Chi-Ming, and 王啟明. "A Study on Spot and Option of Globe Crude Oil." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/42685355869049888340.
Повний текст джерелаАнотація:
碩士大葉大學
國際企業管理學系碩士在職專班
95
The international crude oil price surges upward are one of the serious concerns that will directly impact on international economies. During 1970’s, international erupted by the Egyptian War and the Iranian coup detect, that caused the international crude oil supply contraction. Further on, the initiation also caused two times of international petroleum crisis. At the same time the global economy fell into immediately the stagnation inflation. Afterwards, the various countries start to launch the new policies by focusing on the new energy saving plan and trying to develop the new source of energy hence to replace the existing sources. Therefore the international oil price is beginning to fall back in the average prices. However in this research paper has been pointed out, in the recent years the international oil price starts to continue surges upward again, from January 1999 the average oil price was 12 US dollars per barrel. Not surprising in 2006, the international oil price has already risen upon 70 US dollars per barrel. The petroleum has been concerned as one of the most essential elements in relating to various every day’s human needs. For instance if the international oil price has been dramatic change, it is also making the greatest impact on one nation’s development. Those areas are such as political, economic, armed forces and every day’s human needs and so on. Not only has this, the changing on international oil price has leaded us into the difficult situation. Especially in Taiwan, our nation has heavily relied on crude oil by processing many other industrial activities. In this paper has also been examined the different strategies to avoid the risk by rising upwards of international oil price. In this research paper has also been focused on the areas of long term price re-evaluation. Therefore we may used the data been collected by looking the pervious average price and further on by establishing the general guide line to avoid the international oil price fluency. According to this paper, the author has also been examined the various risk management model such as Binomial Option Pricing Model (BOPM）. This model may help us by forecasting, comparing and contrasting the changed has been made previously. By using this particular model may also provide our government authority; public organization to execute their purchasing strategies.
23
Tsai, Chia-Lun, and 蔡佳倫. "The Price Correlation between Crude Oil Spot and Futures - Applying the Rank Test Method." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/73952373385722394124.
Повний текст джерелаАнотація:
碩士靜宜大學
財務金融研究所
98
Using the non-parametric rank tests proposed by Breitung (2001), we set out in this study to determine whether any non-linear long-run equilibrium relationship exists between the petroleum spot and futures prices. We then estimate the nonlinear and asymmetry Threshold Error-correction model (TECM) with Bivariate GJR-GARCH model to capture the short-run and long-run dynamic adjustments with the asymmetric price and volatility transmissions between the petroleum spot and futures prices. We find that the petroleum futures prices are cointegrated and nonlinear with spot prices in the long-run. This effectively confirms the expectation hypothesis and that asymmetric adjustment for the futures basis toward the long-run value display a positive basis from the long-run equilibrium level more persistently than a negative basis from that level. In the variance equations, we find that when bad news happens in the petroleum spot and futures markets, volatility will increase in its own market. Besides, asymmetric effects are also found in both the petroleum spot and futures markets in our conditional variance models.
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Chang, Wen-Te, and 張文德. "Analysis of Volatile Organic Compounds in Oil Spill and Sports Shoes using Gas Chromatograph / Mass Spectrometer." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/q2gtt9.
Повний текст джерела
25
Shu, Yuanming. "Dark Spot Detection from SAR Intensity Imagery with Spatial Density Thresholding for Oil Spill Monitoring." Thesis, 2010. http://hdl.handle.net/10012/5009.
Повний текст джерелаАнотація:
Since the 1980s, satellite-borne synthetic aperture radar (SAR) has been investigated for early warning and monitoring of marine oil spills to permit effective satellite surveillance in the marine environment.
Automated detection of oil spills from satellite SAR intensity imagery consists of three steps: 1) Detection of dark spots; 2) Extraction of features from the detected dark spots; and 3) Classification of the dark spots into oil spills and look-alikes. However, marine oil spill detection is a very difficult and challenging task. Open questions exist in each of the three stages.
In this thesis, the focus is on the first stage—dark spot detection. An efficient and effective dark spot detection method is critical and fundamental for developing an automated oil spill detection system. A novel method for this task is presented. The key to the method is utilizing the spatial density feature to enhance the separability of dark spots and the background. After an adaptive intensity thresholding, a spatial density thresholding is further used to differentiate dark spots from the background. The proposed method was applied to a evaluation dataset with 60 RADARSAT-1 ScanSAR Narrow Beam intensity images containing oil spill anomalies. The experimental results obtained from the test dataset demonstrate that the proposed method for dark spot detection is fast, robust and effective. Recommendations are given for future research to be conducted to ensure that this procedure goes beyond the prototype stage and becomes a practical application.
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Liao, Min-Ching, and 廖敏晴. "Using Data Mining Techniques to Investigate the Relationships Between International Oil Spot and Taiwan Financial Stock Price." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/25527186227194321698.
Повний текст джерелаАнотація:
碩士國立彰化師範大學
會計學系
104
The purposes of this study are to employ data mining techniques to find out the linkages among international oil spot and financial stock prices of Taiwan-listed shares. This study also investigates the influence factors of fluctuations in oil prices and the degree of direct or indirect effect on financial market of the world and international economy, and go a step further affecting financial stock prices and Taiwan economy. The subject of this research is Taiwan-listed financial shares, and the term of analyzing is from 2006 to the March in 2016. There are many factors cause the fluctuation in stock prices, the variables used in the analysis of this study include international oil spot, financial performances, and macroeconomics factors as main variables and control variables.Adopt decision tree and association rules techniques to analyse the relationships between variables, and adopt time series method to forecast the fluctuations in financial stock index, then verify the analysis results and the forecast. According to the research, the fluctuation in WTI oil spot is the more significant than Brent and Dubai oil spot, judged by 2.7% degree of fluctuations in WTI oil spot, if the drop of the price not exceeds 2.7%, or rise up, the financial stock prices are inclined to climbing up, but the drop of the price exceeds 2.7%, it requires the simultaneous analysis of short-term fluctuations in market rate to further estimate the trend, one of the short-term rate targets of money market: Inter-bank Call Loan Rate.
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ZUO, GUANGDONG, and 左廣東. "Volatility Spillovers and Causality of Carbon Emissions, Oil and Coal Spot and Futures for the EU and USA." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/57f52h.
Повний текст джерелаАнотація:
碩士國立清華大學
計量財務金融學系
106
Abstract Recent research shows that efforts to limit climate change should focus on reducing emissions of carbon dioxide over other greenhouse gases or air pollutants. Many countries are paying substantial attention to carbon emissions to improve air quality and public health. The largest source of carbon emissions from human activities in some countries in Europe and elsewhere is from burning fossil fuels for electricity, heat, and transportation. The prices of fuel and carbon emissions can influence each other. Owing to the importance of carbon emissions and their connection to fossil fuels, and the possibility of Granger (1980) causality in spot and futures prices, returns and volatility of carbon emissions, crude oil and coal have recently become very important research topics. For the USA, daily spot and futures prices are available for crude oil and coal, but there are no daily futures prices for carbon emissions. For the EU, there are no daily spot prices for coal or carbon emissions, but there are daily futures prices for crude oil, coal and carbon emissions. For this reason, daily prices will be used to analyse Granger causality and volatility spillovers in spot and futures prices of carbon emissions, crude oil, and coal. As the estimators are based on QMLE under the incorrect assumption of a normal distribution, we modify the likelihood ratio (LR) test to a quasi-likelihood ratio test (QLR) to test the multivariate conditional volatility Diagonal BEKK model, which estimates and tests volatility spillovers, and has valid regularity conditions and asymptotic properties, against the alternative Full BEKK model, which also estimates volatility spillovers, but has valid regularity conditions and asymptotic properties only under the null hypothesis of zero off-diagonal elements. Dynamic hedging strategies using optimal hedge ratios are suggested to analyse market fluctuations in the spot and futures returns and volatility of carbon emissions, crude oil and coal prices.
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Hsiao, Chinghuan, and 蕭敬桓. "The Time Trend and Unit Root Properties of Crude Oil Spot and Futures Prices with Multiple Structural Breaks." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/58335410885673298704.
Повний текст джерелаАнотація:
碩士國立暨南國際大學
國際企業學系
99
Minimum Lagrange multiplier (LM) unit root tests have two kinds, one is endogenous structural break with one and the other is two endogenous structural breaks proposed by Lee and Strazicich (2003) and Lee and Strazicich (2004), respectively. The research period concerned Brent and West Texas intermediate crude oil spot and futures prices from January 1995 to December 2010. The investigation adopted both approaches to estimate the possible trends, potential break points, as well as the stationarity of the spot and futures crude oil prices. In addition, the study considered different horizon and frequency characteristics of the data to examine whether there resulted in different situations. Moreover, we further utilize the concept of structural breaks to forecast the crude oil price. Under different kinds of data horizons, the empirical result indicated the eight crude oil prices series cannot be rejected the unit root hull hypothesis, and implying that even taking the structural breaks into consideration which still could not explain the stationary of the series. Consistent with the Maslyuk and Smyth (2008), the crude oil prices move as random walk process. No matter in one or two breaks models, the findings all pose significant time trends. The possible reason is the time trend has already altered, and the international specific events can explain this kind of change. Finally, we further employ weekly data to test WTI crude oil prices in ex-ante 2007 period, and the numerical result reveals that the oil prices are trend stationary. In the forecasting aspects, the study applied autoregressive models with one lag perform a satisfactory job than Random Walk in terms of forecasting accuracy.
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Pan, Chi-ching, and 潘子正. "RELATIONSHIP BETWEEN THE BASIS, OPEN INTERNET AND THE FUTURE TREND OF SPOT--AN IMPLICATION OF THE WEST TEXAS INTERMEDIATE CRUDE OIL." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/qu6c8r.
Повний текст джерелаАнотація:
碩士南華大學
財務金融學系財務管理碩士班
101
Based on the futures price discovery function ,we want to understand the relationship between the market information of futures and future trend of spot price. This study selects the West Texas intermediate crude oil as a sample. We organize the direction variables and the implied energy variables by the basis and open interest to study their influences on the future direction of future spot price movements by the logistic regression model. The selection period was from 2th of January 2009 to 12th of August 2012. The empirical analysis of this study revealed the following: (1) For studying the problem about the relationship of the market information of futures and future direction of future spot price movement, considering the momentum concept and average absolute value of basis are necessary. (2) Open interest can strengthen the effects of directional variables. (3) The future price discovery function caused by the direction variable only occurred when the implied energy variables are large enough.
30
劉守芬. "A Study on the Relationship among Brent Crude Oil Price, Balti Capsize Index, Iron Ore Spot Price, and Steel Price Index." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/34k65a.
Повний текст джерелаАнотація:
碩士國立高雄科技大學
國際企業系
107
This study took four variables which are the Baltic capsize index, the BRENT crude oil price, the iron ore spot price, and the global steel price index as our study object. The period is from week 1, 2014 to week 19, 2018 with 228 weekly data. Using ADF and PP unit root tests, Johansen co-integration test, Vector error correction model, Granger causality test, impulse response function, Variance decomposition to verify the relationship among all variables. Johansen co-integration test result found that there is a long-term equilibrium relationship among the variables. In short-term dynamic relationship verification, Vector error correction model results showed that the Baltic capsize index be affected by the BRENT crude oil price’s previous period. The iron ore spot price CME will be affected by its own previous period. Brent crude oil price be affected by the global steel price index’s previous period. Granger causality test results obtained the Brent crude oil price has one-way positive leading relationship to the Baltic capsize index. The steel price index has one-way positive leading relationship to the Brent crude oil price and the iron ore spot price. The error variability decomposition analysis found the Balti capsize index and the Brent crude oil price are exogenous explanatory variables, the iron ore spot price and the global steel price index are endogenous explanatory variables. Keywords: Balti Capsize Index, Granger causality test, Johansen Co-integration test, Vector error correction model
31
Wang, Chih-Hao, and 王植顥. "Dynamic Price Jump and Value-at-Risk for the Minimum Variance Hedging Portfolio: The Case of Brent Crude Oil Spot and Futures Price." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/27950233066762045411.
Повний текст джерелаАнотація:
碩士淡江大學
管理科學學系碩士班
100
How to reduce portfolio risk an very important issue based on diversification of investment products. A highly relationship was shown on futures and spot market, so making use of futures contracts to avoid the spot market changes in price shocks has become the key to investors to maintain the profit and loss. The study is to compute Value-at-Risk in the long trading position for the minimum variance hedging portfolio by using GARCH(1,1) model, bivariate GARCH (1,1) model and bivariate ARJI-GARCH(1,1) model at two significant levels. The sample daily data is Brent crude oil closing price in spot and furtures market. Moreover, the study is to evaluate the different models by using backtesting method based on likelihood ratio test proposed by Kupiec (1995) and Christoffersen(1998). The study showed that the bivariate ARJI-GARCH (1,1) model at the significance level of 5% and 1% are statistically significant, indicating that the bivariate ARJI-GARCH(1,1) model can accurately describe the discontinuous characteristics of the fat tail and price. This result can provide valuable information for financial institutions to assess the portfolio risk. It improves the estimated performace under the tail distribution and further forecast the financial asset return volatility, fat tail, and the discontinuous price.
32
Lin, Che-Yu, and 林哲宇. "Dynamic price jump and value-at-risk for the minimum variance hedging portfolio: The case of the WTI crude oil spot and futures prices." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/72972345034038334687.
Повний текст джерелаАнотація:
碩士淡江大學
管理科學學系碩士班
100
International crude oil prices of volatility severely make investors bear huge loss in recent years. Thus, crude oil futures become one of financial instruments of hedge. The crude oil prices bring out discontinuous phenomena, because of the rare events. In this study, it estimates the conditional value-at-risk of the minimum variance hedging portfolio by using the bivariate CBP-GARCH model proposed by Chan(2003). Moreover, this study is to evaluate the accuracy of the bivariate CBP-GARCH model by using backtesting method based on likelihood ratio test proposed by Kupiec(1995) and conditional coverage test proposed by Christoffersen(1998).The empirical results are as follows. The conditional value-at-risk model of the minimum variance hedging portfolio by using the bivariate CBP-GARCH model passes the backtesting; however, the conditional value-at-risk model of the minimum variance hedging portfolio by using non-hedge model and the bivariate DCC-GARCH model do not pass. The conditional value-at-risk model of the minimum variance hedging portfolio by using the bivariate CBP-GARCH model has high accuracy; it is because that it can capture dynamic jump process and jump correlation. Therefore, if we just consider the dynamic volatility process, it could underestimate risk and let investors bear the loss than expected. This result can be used as a hedge reference for investors.
33
Lee, Hung-Yuan, and 李宏遠. "Optimization of Manufacturing Parameters for Safe Part Spot-welding of Automobile Industry Using Lean Production and Six Sigma Methodology ―An Application to Car Cross member and oil tank parts." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/36271862476514807489.
Повний текст джерелаАнотація:
碩士元智大學
工業工程與管理學系
97
This study implements the lean and six-sigma DMAIC management tool to analyze and improve the loose problem of spot welding of auto cross member and the oil tank. In welding machine configuration, electric current, machine pressure, and welding time are critical factors of spot welding. The final welded part is verified by destructive tests to see if it conforms to the specification or standard. The auto cross member and the oil tank parts directly involve human safety and are considered the safety parts by auto manufacturer. If loose welding problem happens and causes injury or casualty of passengers, the manufacturer would face strong pressure for a recall. It not only harms manufacturer’s reputation, but the manufacturer may also incur huge liability for damages. Therefore, almost all auto manufacturers put high emphasis on the safety parts. The quality of spot welding of #3 cross member and the oil tank of certain auto type is studied. By the design of experiment, the optimal configuration is achieved to reduce the loose problem of spot welding.
34
Kwon, Tae-Jung. "SAR Remote Sensing of Canadian Coastal Waters using Total Variation Optimization Segmentation Approaches." Thesis, 2011. http://hdl.handle.net/10012/5893.
Повний текст джерелаАнотація:
The synthetic aperture radar (SAR) onboard Earth observing satellites has been acknowledged as an integral tool for many applications in monitoring the marine environment. Some of these applications include regional sea-ice monitoring and detection of illegal or accidental oil discharges from ships. Nonetheless, a practicality of the usage of SAR images is greatly hindered by the presence of speckle noises. Such noise must be eliminated or reduced to be utilized in real-world applications to ensure the safety of the marine environment. Thus this thesis presents a novel two-phase total variation optimization segmentation approach to tackle such a challenging task. In the total variation optimization phase, the Rudin-Osher-Fatemi total variation model was modified and implemented iteratively to estimate the piecewise smooth state by minimizing the total variation constraints. In the finite mixture model classification phase, an expectation-maximization method was performed to estimate the final class likelihoods using a Gaussian mixture model. Then a maximum likelihood classification technique was utilized to obtain the final segmented result. For its evaluation, a synthetic image was used to test its effectiveness. Then it was further applied to two distinct real SAR images, X-band COSMO-SkyMed imagery containing verified oil-spills and C-band RADARSAT-2 imagery mainly containing two different sea-ice types to confirm its robustness. Furthermore, other well-established methods were compared with the proposed method to ensure its performance. With the advantage of a short processing time, the visual inspection and quantitative analysis including kappa coefficients and F1 scores of segmentation results confirm the superiority of the proposed method over other existing methods.