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Application of the Continuous EUR Method to Estimate Reserves in Unconventional Gas ReservoirsCurrie, Stephanie M. 2010 August 1900 (has links)
Reserves estimation in unconventional (low/ultra-low permeability) reservoirs has become a topic of increased interest as more of these resources are being developed, especially in North America. The estimation of reserves in unconventional reservoirs is challenging due to the long transient flow period exhibited by the production data. The use of conventional methods (i.e., Arps' decline curves) to estimate reserves is often times inaccurate and leads to the overestimation of reserves because these models are only (theoretically) applicable for the boundary-dominated flow regime. The premise of this work is to present and demonstrate a methodology which continuously estimates the ultimate recovery during the producing life of a well in order to generate a time-dependent profile of the estimated ultimate recovery (EUR). The "objective" is to estimate the final EUR value(s) from several complimentary analyses.
In this work we present the "Continuous EUR Method" to estimate reserves for unconventional gas reservoirs using a rate-time analysis approach. This work offers a coherent process to reduce the uncertainty in reserves estimation for unconventional gas reservoirs by quantifying "upper" and "lower" limits of EUR prior to the onset of boundary-dominated flow. We propose the use of traditional and new rate-time relations to establish the "upper" limit for EUR. We clearly demonstrate that rate-time relations which better represent the transient and transitional flow regimes (in particular the power law exponential rate decline relation) often lead to a more accurate "upper" limit for reserves estimates — earlier in the producing life of a well (as compared to conventional ("Arps") relations). Furthermore, we propose a straight line extrapolation technique to offer a conservative estimate of maximum produced gas which we use as the "lower" limit for EUR. The EUR values estimated using this technique continually increase with time, eventually reaching a maximum value.
We successfully demonstrate the methodology by applying the approach to 43 field examples producing from 7 different tight sandstone and shale gas reservoirs. We show that the difference between the "upper" and "lower" limit of reserves decreases with time and converges to the "true" value of reserves during the latter producing life of a well.
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Heavy-Tailed Innovations in the R Package stochvolKastner, Gregor January 2015 (has links) (PDF)
We document how sampling from a conditional Student's t distribution is implemented in stochvol. Moreover, a simple example using EUR/CHF exchange rates illustrates how to use the augmented sampler. We conclude with results and implications. (author's abstract)
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Χρήση γενετικού αλγόριθμου για βελτιστοποίηση δομής, παραμέτρων τεχνητών νευρωνικών δικτύων και εφαρμογή της υβριδικής μεθόδου σε προβλήματα από τον χώρο της οικονομίαςΑμοργιανιώτης, Θωμάς 24 January 2012 (has links)
Τα πολυεπίπεδα νευρωνικά δίκτυα έχουν εφαρμοστεί στο παρελθόν με μεγάλη επιτυχία στην πρόβλεψη χρονοσειρών από το χώρο της οικονομίας. Στην πράξη όμως παρουσιάζουν διάφορα προβλήματα όπως:
Εύρεση του βέλτιστου υποσυνόλου χαρακτηριστικών και χρησιμοποίησή τους σαν εισόδου.
Εύρεση της βέλτιστης δομής (επίπεδα κρυφών νευρώνων, αριθμός κρυφών νευρώνων).
Εύρεση των βέλτιστων τιμών των παραμέτρων του αλγορίθμου εκπαίδευσης των τεχνητών νευρωνικών δικτύων (παράμετρος μάθησης, παράμετρος ορμής κλπ.)
Σκοπός της διπλωματικής αυτής εργασίας είναι η δημιουργίας μιας υβριδικής μεθόδου γενετικών αλγορίθμων και νευρωνικών δικτύων. Ο γενετικός αλγόριθμος θα είναι υπεύθυνος στην εύρεση του βέλτιστου συνδυασμού των παραπάνω προς αναζήτηση παραμέτρων του νευρωνικού δικτύου.
Η υβριδική αυτή μέθοδος θα εφαρμοστεί στο πρόβλημα της πρόβλεψης του δείκτη ASE-20 του ελληνικού χρηματιστηρίου καθώς και στο πρόβλημα της πρόβλεψης της ισοτιμίας δολαρίου-Ευρώ. / In the present thesis we attempted to create a combination of genetic algorithms and neural networks. The proposed methodology was applied to the problem of predicting the exchange rate between EUR/USD and the Greek stock market ASE 20 index.
The idea of combining these two techniques for the solving of the above mentioned problems emerged by their innate ability of finding solutions where traditional methods fail. On one hand, neural networks imitate the human brain procedures and on the other, genetic algorithms imitate the physical evolution process. In fact, both techniques copy some of nature’s functions. Artificial neural networks, through educating and generalizing manage to learn a problem and provide solutions to it. Genetic algorithms, through the evolution circle can overcome local minima or maxima and reach global ones.
Due to their compact, parallel and distributed format and their ability of learning, neural networks make the solving of complicated problems possible, by dividing them in smaller projects, which are taken over by the neural networks according to their capabilities.
Due to the advantages of neural networks and genetic algorithms we created a combination of them to predict the exchange rate between EUR/USD and the Greek stock market ASE 20 index.
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Optimering utav antalet produkter på en EUR-pall genom framtagningav ny förpackningslåda / Optimization of the number of products on a EUR-pallet through development of a new packaging boxGustafsson, Filip January 2019 (has links)
Detta är en studie om hur en framtagning utav en transportlåda på företaget AstraZeneca utfördes. Syftet med studien var att transportlådan skulle ersätta tre olika transportlådor som användes för att paketera tre olika storlekar på en förpackning som innehåller samma produkt. Förpackningarna har samma höjd och bredd men har olika längdmått beroende på hur många produkter som ska in i samma förpackning. Den första förpackningen har 1 produkt i sig, den andra förpackningen har 2 produkter i sig och den tredje förpackningen har 3 produkter i sig. För att ta sig an problemet användes linjärprogrammering för att hitta största gemensamma längdmått som ligger inom dimensionerna för en standardiserad EUR-pall. Utöver framtagningen utav lådan utfördes en flödesanalys samt en kostnadsanalys för att hitta förbättringsområden och kostnadsreduceringar i flödet. Studien lyckades att ta fram en låda där all tre olika förpackningar fick plats i och utöver det medförde den framtagna lådan att antalet produkter på pall ökade med 20% för förpackningen med 1 produkt i sig, 12 % för förpackningen med 2 produkter i sig och den sista förpackningen har samma antal produkter på pall jämfört med föregående låda. Kostnadsanalysen visade en kostnadsreducering på 1,96 mkr per år på inköpspriset jämfört med inköpskostnader för de tre tidigare transportlådorna. Slutsatsen för denna studie blev därför att det är en förbättring att införa den framtagna lådan istället för att ha tre separata transportlådor för respektive förpackning. / This is a study to display the process of developing a transportation box for the pharmaceutical company AstraZeneca. The purpose of study is to develop a transportation box in such a way so it could replace three already existing transportation boxes and enable these products to use the same transportation box. The products contain the same pharmaceutical product but has different dimensions for their respective containers where the height and the width is the same on all containers but has different length measurements depending on the number of pharmaceutical products in them. The first container contains 1 product, the second container contains 2 products and the third container contains 3 products. The solution to this problem was to use linear programming to establish a common length that the three containers share but is not larger than the dimensions on a standard EUR-pallet. Furthermore, the study was using a valueflow analysis and a cost analysis to determine which areas this transportation box can improve different processes within the company’s material flow. The linear programming succeeded in finding a common length for the three containers and a prototype was constructed in collaboration with the supplier. With the developed transportation box the study managed to increase the quantity on each pallet for 2 out of the 3 containers. The first container increased the quantity for each pallet with 20% and the increased the quantity for the second container with 12%. The quantity for the third container on each pallet remained the same as before. Furthermore, the cost analysis showed a reduced cost for purchasing the transportation box by 1,96 million SEK. This number is a comparison of the cost for the three already existing transportation boxes and an estimated prize on the developed transportation box. The verdict for this study is to implement the developed box because of the reduced costs and the improvements in the material flow that the box provides.
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Cizí měna v účetnictví podnikatelů v ČR a jednotná měna Eurozóny na příkladu SR / Foreign currency in accounting czech entrepreneur and single currecncy illustrated by an example Slovak RepublicBerková, Eva January 2011 (has links)
The primary concentration of the diploma thesis is conversion from domestic currency to single currency (EURO) from an accounting point of view. On the one side the thesis deal with foreign currency and it`s effect on accounting of Czech entrepreneurs and on the economics profit and loss. On the other side thesis show the solution for the entrepreneurs, which mainly deal in euro. Conversion is described on the example of the Slovak Republic. The thesis gives an overview of conversion`s process and interpretive examples
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Fundamentální analýza měnového kurzu EUR/USD / Fundamental analysis of the exchange rate of EUR/USDŠevčík, Václav January 2009 (has links)
The aim of this thesis is empirical verification of the fundamental theory of exchange rate determination in the case of the currency pair EUR/USD. The theoretical part is devoted to the issue of exchange rate theory, with emphasis on the importance of the currency pair EUR/USD, and major characteristics of the fundamental theory of exchange rate determination. Attention is also paid to methods of analysis of time series, which will be used in the analytical part. The analytical part is devoted to an empirical verification of the underlying theories. On the basis of these theories are developed econometric models, which are then tested using the methods of linear regression and cointegration. The results of the models and their relevance are discussed in conclusion.
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Gas flow through shaleSakhaee-Pour, Ahmad 14 November 2013 (has links)
The growing demand for energy provides an incentive to pursue unconventional resources. Among these resources, tight gas and shale gas reservoirs have gained significant momentum because recent advances in technology allowed us to produce them at an economical rate. More importantly, they seem likely to contain a significant volume of hydrocarbon. There are, however, many questions concerning hydrocarbon production from these unconventional resources. For instance, in tight gas sandstone, we observe a significant variability in the producibilities of wells in the same field. The heterogeneity is even present in a single well with changes in depth. It is not clear what controls this heterogeneity. In shale gas, the pore connectivity inside the void space is not well explored and hence, a representative pore model is not available. Further, the effects of an adsorbed layer of gas and gas slippage on shale permeability are poorly understood. These effects play a crucial role in assigning a realistic permeability for shale in-situ from a laboratory measurement. In the laboratory, in contrast to in-situ, the core sample lacks the adsorbed layer because the permeability measurements are typically conducted at small pore pressures. Moreover, the gas slippages in laboratory and in-situ conditions are not identical. The present study seeks to investigate these discrepancies. Drainage and imbibition are sensitive to pore connectivity and unconventional gas transport is strongly affected by the connectivity. Hence, there is a strong interest in modeling mercury intrusion capillary pressure (MICP) test because it provides valuable information regarding the pore connectivity. In tight gas sandstone, the main objective of this research is to find a relationship between the estimated ultimate recovery (EUR) and the petrophysical properties measured by drainage/imbibition tests (mercury intrusion, withdrawal, and porous plate) and by resistivity analyses. As a measure of gas likely to be trapped in the matrix during production---and hence a proxy for EUR---we use the ratio of residual mercury saturation after mercury withdrawal (S[subscript gr]) to initial mercury saturation (S[subscript gi]), which is the saturation at the start of withdrawal. Crucially, a multiscale pore-level model is required to explain mercury intrusion capillary pressure measurements in these rocks. The multiscale model comprises a conventional network model and a tree-like pore structure (an acyclic network) that mimic the intergranular (macroporosity) and intragranular (microporosity) void spaces, respectively. Applying the multiscale model to porous plate data, we classify the pore spaces of rocks into macro-dominant, intermediate, and micro-dominant. These classes have progressively less drainage/imbibition hysteresis, which leads to the prediction that significantly more hydrocarbon is recoverable from microporosity than macroporosity. Available field data (production logs) corroborate the higher producibility of the microporosity. The recovery of hydrocarbon from micro-dominant pore structure is superior despite its inferior initial production (IP). Thus, a reservoir or a region in which the fraction of microporosity varies spatially may show only a weak correlation between IP and EUR. In shale gas, we analyze the pore structure of the matrix using mercury intrusion data to provide a more realistic model of pore connectivity. In the present study, we propose two pore models: dead-end pores and Nooks and Crannies. In the first model, the void space consists of many dead-end pores with circular pore throats. The second model supposes that the void space contains pore throats with large aspect ratios that are connected through the rock. We analyze both the scanning electron microscope (SEM) images of the shale and the effect of confining stress on the pore size distribution obtained from the mercury intrusion test to decide which pore model is representative of the in-situ condition. We conclude that the dead-end pores model is more representative. In addition, we study the effects of adsorbed layers of CH₄ and of gas slippage in pore walls on the flow behavior in individual conduits of simple geometry and in networks of such conduits. The network is based on the SEM image and drainage experiment in shale. To represent the effect of adsorbed gas, the effective size of each throat in the network depends on the pressure. The hydraulic conductance of each throat is determined based on the Knudsen number (Kn) criterion. The results indicate that laboratory measurements made with N₂ at ambient temperature and 5-MPa pressure, which is typical for the transient pulse decay method, overestimate the gas permeability in the early life of production by a factor of 4. This ratio increases if the measurement is run at ambient conditions because the low pressure enhances the slippage and reduces the thickness of the adsorbed layer. Moreover, the permeability increases nonlinearly as the in-situ pressure decreases during production. This effect contributes to mitigating the decline in production rates of shale gas wells. Laboratory data available in the literature for methane permeability at pressures below 7 MPa agree with model predictions of the effect of pressure. / text
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Kategorie determinace: strategie překladu španělských administrativně-právních textů do češtiny. / Category of Determination: Translation strategy of Spanish administrative-and-law texts into Czech.JANUŠOVÁ, Adéla January 2014 (has links)
The main theme of this thesis is the category of determination in the Spanish language. Considering that this category is very large in spanish language we have focused in detail on the article, especially the indefinite article. This work is devided into two parts, the theoretic and the practical part. The theoretic part has been devoted to definitions and main characterization of the article, primarily the indefinite article. This issue is looked upon from the point of different publications that discuss it more or less thoroughly. Considering that the category of determination itself does not exist in the Czech language we briefly draw other mediums to express this phenomenon, especially the word order. For the practical part the qualitative methods were used.In this part the use of determinants was analyzed in administrative and legal texts, specifically in two texts from the web page www.Eur-Lex.eu, in one text from Boletín Oficial del Estado and in one law of the Czech Ministry of Education.
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Analýza vlivu mediálně významných událostí na finanční trhy / Analysis of the Impact of Media Important Events on Financial MarketsSiuda, Vojtěch January 2017 (has links)
This thesis analyses the impact of announcements of macroeconomic indicators in United States on price development of the VIX Futures, S&P500 Futures and EUR/USD FX rate. Theoretical part contains construction and description of individual markets. Empirical part investigates the reaction of market prices after 1, 10 and 30 minutes after announcement of an individual indicator value on a market surprise demonstrated as a difference between reported value and analysts' expectations. We tried to find a systematic reaction of market participants and the pace of absorption of new information into the market price. There have been found minimum of situations, where we explained the market move as a linear combination of market surprise. However, there was a several cases, where the market did not adjust to announced information quickly and was inefficient in a short period. In the second part of empirical research we tested all significant models on an out-sample data. The goal was to determine whether the market inefficiencies persisted and stable profit could be achieved. We analysed the brutto performance, then netto performance including all transaction costs. Finally, we defined a simple trading rules with a purpose of profit stabilization and lowering the riskiness of trades. For VIX Futures and EUR/USD markets we achieved a low loss, respectively negligible profit. For S&P 500 Futures we obtained a profit strategies for all selected indicators, total profit was high with a very low volatility of invested capital.
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Projekt konverze měny SKK na EUR v ERP SAP / Project Conversion of SKK to EUR in ERP SAPKuročkin, Michal January 2008 (has links)
This diploma work is concerned about of euro conversion and its impact on information system ERP SAP in large multinational company. Theoretical part is focused on general scenarios of euro adoption and progress of adoption of euro in Slovakia. Next chapter is describing methods of project management, definitions, subjects and stakeholders, organizational structures and phases of the project. Theoretical parts ends with description of ERP functionality, basic functional modules and general information about ERP SAP. Second, practical part is dedicated to project of conversion of euro in ERP SAP itself. Practical part begins with describing of company, organizational structure and IS architecture. Next chapters are focused on analysis of particular subprojects defined on scope of general euro conversion project, their schedule and reasoning of the sequence of each subproject.
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