39 research outputs found
Verification of confinement impact on flow using a black oil simulator
No full textIncludes bibliographical references.2017 Spring.This research study for a Master of Science degree has been conducted under the Unconventional Reservoir Engineering Project (UREP) at the Marathon Center of Excellence for Reservoir Studies (MCERS) in the Petroleum Engineering Department of Colorado School of Mines. The main objective of the research is to verify the impact of confined PVT behavior (pore size impact) on flow in unconventional reservoirs by considering the impact of gas-oil drainage capillary pressure on oil and gas production (depletion) profiles. Unlike conventional oil and gas reservoirs, pore sizes in unconventional resources can be prohibitively small for the flow of hydrocarbon fluids. Moreover, extreme pore confinement causes deviations from conventional (bulk) fluid phase behavior. When confinement increases, capillary pressure between the phases occupying the pore system increases. Black oil simulators that are commonly used in the industry are not formulated to handle the impact of capillary pressure on phase behavior, and they do not evaluate fluid properties at corresponding gas- and oil-phase pressures. This may be a significant problem in simulation of nano-porous unconventional reservoirs where fluid phase equilibrium calculations are affected due to capillary forces in confinement. Studies have shown that the confinement manifests itself as suppression in bubble-point pressure which extends the under-saturated portion of the formation-volume-factor curve for oil. This study uses a black-oil simulator, COZSim, which was developed earlier under UREP to include the capillary-pressure impact on phase behavior. In COZSim, individual phase pressures are derived from the bulk pressure using the capillary pressure and the excess pressure, which is the additional pressure required for the two phase to be in a thermodynamic equilibrium. A correlation that represents the bubble-point suppression as a function of the solution gas-oil ratio () and capillary pressure () is used in the simulator. Sensitivity tests have been performed to show the impact of phase behavior due to confinement on fluid flow and production from wells in unconventional reservoirs. Various simulation models have been built to study the impact of single-, dual-, triple- and quintuple-porosity formulations on calculated oil and gas production profiles at different capillary pressure values. Results of the simulations show considerable dependence of oil and gas production not only on the magnitude of the confinement but also on the formulation that is used
Comparison of Lanczos Decomposition Method LDM and Conventional Implicit Time-Stepping Method ITSM for Numerical Reservoir Simulation
No full textA Black Oil Simulator that Includes the Impact of Capillary Pressure on Phase Behavior in Nano-Porous Unconventional Reservoirs
No full textUplift capacity of helical piles in thawing permafrost
No full textThis thesis focuses on the investigation of the effect of subsurface temperatures on the axial capacity of helical piles embedded in silty permafrost soils. The overall of goals of this thesis are (1) characterization of the impact of different environmental and loading conditions on the axial capacity of helical piles and (2) development of meaningful relationships on the physical processes in the subsurface, especially the interdependency of thermo-hydraulic behavior and the load-displacement behavior of piles. A balanced numerical and experimental campaign is carried out to understand the mechanisms that affect pile capacity with warming temperatures in a silt layer. A series of laboratory-scale pile experiments are performed, and the results are compared to predictions from theoretical methods. A numerical model is developed and validated against experimental results from the literature and is used to estimate load-displacement curves and uplift capacity of helical piles. The predictive numerical model is further used to probe more information about critical soil parameters that affect the capacity of piles in frozen soils.
The laboratory-scale model consists of a double-helix helical pile embedded in an unsaturated Bonny silt layer inside a tank instrumented with an array of dielectric sensors to measure temperature, volumetric water content, and suction. The pile-soil system is frozen then thawed to different temperatures. Then, the pile is subjected to pull-out loading at constant displacement rates. The experimental program included seven tests performed at soil temperatures of -8˚C, -6˚C, -2˚C, -0.2˚C, and 17˚C. The experiment performed at -6˚C was repeated to investigate the impact of strain rate, and the experiment at 17˚C was repeated to understand the effect of thaw rate on pile axial capacity. The helical pile experiences brittle failures at displacements of about 0.5D for soil temperatures below -2˚C, where D is the helix diameter. Ductile behavior is evident when soil temperature is above -0.2˚C, as the peak load is reached at larger displacements of about 1D.
Dielectric sensor measurements show that unfrozen water content decreases with temperature, with the most significant decrease occurring between 0 and -2˚C for the compacted silt. The axial capacity of helical piles increases linearly with decreasing temperatures below 0˚C, while it increases exponentially with decreasing degrees of saturation. For the experiments conducted at the same temperature but different strain rates, the slower pull-out rate results in higher axial capacity. Although the differences in pile capacity are very slight, this behavior is unexpected because viscous effects from the unfrozen water should increase the capacity at higher strain rates. Slight variations in temperature and unfrozen water content can explain this, indicating that those parameters may have a more significant effect on axial capacity. For the experiments conducted at the same strain rate but different thaw rates, the test with a faster thaw rate reaches a higher axial capacity. This may be due to more prevalent water migration in the test since slow thawing may lead to higher water contents at the center of the tank where the pile is located.
Axial capacities from experiments are compared with predictions from theoretical helical pile capacity equations. Estimates of undrained shear strength from existing temperature correlations are employed in the theoretical calculations. It was concluded that predicted axial capacities show a good match with experimental results at temperatures below 0°C, but not for the fully thawed condition at room temperature. It is possible that for unfrozen soil, the undrained shear strength could not be predicted using the existing linear correlation since it is governed by other parameters, i.e., particle shape, pore size distribution, and water content, when ice is not present.
The analyses and conclusions drawn from this study using the data sets from empirical observations, theoretical models, and numerical simulations will significantly contribute to design guidelines of helical piles installed in frozen soils and will be instrumental in adaptation strategies for sustainable development in cold regions.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2023-05-01The student, Sofia Fernandez Santoyo, accepted the attached license on 2021-04-28 at 09:08.The student, Sofia Fernandez Santoyo, submitted this Thesis for approval on 2021-04-28 at 09:27.This Thesis was approved for publication on 2021-04-28 at 13:44.DSpace SAF Submission Ingestion Package generated from Vireo submission #16597 on 2021-09-16 at 20:14:41Made available in DSpace on 2021-09-17T04:06:56Z (GMT). No. of bitstreams: 2
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Non-muscle invasive bladder cancer tissues have increased base excision repair capacity
No full textThe molecular mechanisms underlying the development and progression of bladder cancer (BC) are complex and have not been fully elucidated. Alterations in base excision repair (BER) capacity, one of several DNA repair mechanisms assigned to preserving genome integrity, have been reported to influence cancer susceptibility, recurrence, and progression, as well as responses to chemotherapy and radiotherapy. We report herein that non-muscle invasive BC (NMIBC) tissues exhibit increased uracil incision, abasic endonuclease and gap-filling activities, as well as total BER capacity in comparison to normal bladder tissue from the same patient (p<0.05). No significant difference was detected in 8-oxoG incision activity between cancer and normal tissues. NMIBC tissues have elevated protein levels of uracil DNA glycosylase, 8-oxoguanine DNA glycosylase, AP endonuclease 1 and DNA polymerase beta protein. Moreover, the fold increase in total BER and the individual BER enzyme activities were greater in high-grade tissues than in low-grade NMIBC tissues. These findings suggest that enhanced BER activity may play a role in the etiology of NMIBC and that BER proteins could serve as biomarkers in disease prognosis, progression or response to genotoxic therapeutics, such as Bacillus Calmette-Guerin.Muftuoglu, M (corresponding author), Acibadem Mehmet Ali Aydinlar Univ, Dept Med Biotechnol, TR-34752 Istanbul, Turkey ; Acibadem Mehmet Ali Aydinlar Univ, Dept Mol Biol & Genet, TR-34752 Istanbul, Turkey.
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TURKISH PRIMARY SCHOOL STUDENTS' INVOLVEMENT IN CLASSROOM ACTIVITIES
No full textMeasuring students' interest and involvement in classroom activities at all stages of education, from preschool to upper secondary school, provides a better understanding of learning processes that enable the acquisition of abilities specific to a certain field. The purpose of this cross -age study was to investigate primary school students' involvement level in classroom activities. The sample consisted of 560 students studying in the first, second, third, and fourth grades at primary schools affiliated with a city in Turkey's inner Aegean area. The data were collected through The Demographic Information Form and Leuven Involvement Scale. The research revealed that students in the 1st, 2nd, 3rd, and 4th grades in primary school had a moderate involvement level. It was found that there was a significant difference between the involvement levels of primary school students and the gender, course type, and professional experience of the teacher, but there was no significant difference between the grade levels of the students. It was recommended to use current methods and strategies to increase the level of involvement of students in classroom activities and to make arrangements to improve involvement in the learning environment.Scientific Research Projects Council of Afyon Kocatepe University; [19.SOS.BIdot;L.09]This research was published as a master's thesis by the first author under the supervision of the second author at Afyon Kocatepe University in 2021. This research is from the project (No 19.SOS.B & Idot;L.09) and funded by the Scientific Research Projects Council of Afyon Kocatepe University
EU democratic governance promotion towards Central Asia and illiberal regional powers
No full textThe EU's engagement with Central Asia has evolved significantly since the 1990s from being the region's largest donor, even if an invisible one, to a strategic partner with a more comprehensive policy framework. The steadily increasing geostrategic importance of the region has pushed the EU to search for new ways to regain its presence in a field characterised by the growing influence of illiberal powers such as Russia and China. At the time, transformative power discussions over the EU's actorness stemming from the successful transition of Central and Eastern European states to liberal democracies during their accession processes constitute a new impetus to shape its policies towards Central Asia by incorporating declared EU values, including democracy, human rights, and the rule of law. Yet, the EU's democratic governance promotion policies, handled as regional at the very beginning of relations, have started to show differences according to the individual country in question. This chapter addresses the idea that this differentiation in EU democratic governance promotion across Central Asian countries emanates not only due to the differences in their local contexts but also due to the presence and leverage of illiberal regional powers over such countries. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2022
Multi-zone optimisation of high-rise buildings using artificial intelligence for sustainable metropolises. Part 2: Optimisation problems, algorithms, results, and method validation
No full textHigh-rise building optimisation is becoming increasingly relevant owing to global population growth and urbanisation trends. Previous studies have demonstrated the potential of high-rise optimisation but have been focused on the use of the parameters of single floors for the entire design; thus, the differences related to the impact of the dense surroundings are not taken into consideration. Part 1 of this study presents a multi-zone optimisation (MUZO) methodology and surrogate models (SMs), which provide a swift and accurate prediction for the entire building design; hence, the SMs can be used for optimisation processes. Owing to the high number of parameters involved in the design process, the optimisation task remains challenging. This paper presents how MUZO can cope with an enormous number of parameters to optimise the entire design of high-rise buildings using three algorithms with an adaptive penalty function. Two design scenarios are considered for quad-grid and diagrid shading devices, glazing type, and building-shape parameters using the setup, and the SMs developed in part 1. The optimisation part of the MUZO methodology reported satisfactory results for spatial daylight autonomy and annual sunlight exposure by meeting the Leadership in Energy and Environmental Design standards in 19 of 20 optimisation problems. To validate the impact of the methodology, optimised designs were compared with 8748 and 5832 typical quad-grid and diagrid scenarios, respectively, using the same design parameters for all floor levels. The findings indicate that the MUZO methodology provides significant improvements in the optimisation of high-rise buildings in dense urban areas
The protection of AI-generated works under European copyright law : toward adoption of a neighbouring rights approach
No full textIndividuals today create works that outperform their qualitative and quantitative capacities, thanks to generative models such as DALL-E and Midjourney, and sometimes even win awards with these works. These intelligent technologies – incorporated by many into their creative endeavours – throw into question the boundaries of copyright law, built as it is upon human creativity.
The unpredictability and autonomous behaviour of AI technologies challenge many of the traditional paradigms of legal systems. The European Union has reacted to these fractures by publishing two Proposals for the AI Act and the AI Liability Directive. The Proposals sketch out a proportionate and future-proof framework for the legal protection of these technologies; but also leave many questions with respect to copyright law unaddressed. This thesis helps to fill this legal gap by analyzing the position of AI-generated works in the EU copyright system, and in so doing, contributes to the European policy-making process.
This research comprises five chapters. Chapter One begins with the introduction to the research question. Chapters Two and Three outline the relevant aspects of AI technologies and Union law, respectively. Chapter Four assesses the compatibility of a number of protection models for AI-generated works within the EU copyright system, analyzing whether these technologies can dethrone the human creator, who is at the center of this system, and discard her from the creative process. Under the European copyright system, the author stamps the works with her personal touch, the protection period is based on her life duration, and moral rights are extensions of her personality. This chapter interrogates how the ‘author’, the protagonist of copyright law, can disappear in the creative process, as well as how the concepts of ownership and neighbouring rights could correspondingly evolve. Chapter Five, finally, highlights the need for reform in the legal framework for AI-generated works. It suggests that a sui generis neighbouring right regime would provide much needed transparency and proportionality for AI-generated works, which are, in fact, already a part of copyright systems without explicit acknowledgment of the AI contribution.Law, Peter A. Allard School ofGraduat
Imaginary structures with an experimental grammar for the island of San Giacomo in Paludo: extracting an alphabet from Saverio Muratori, Luchino Visconti and a syntax from Philippe Sollers
No full textLAUREA MAGISTRALEQuesta tesi si concentra su un approccio sperimentale che costituisce la base sia per le tecniche di rappresentazione che per il progetto architettonico esplorato in questa ricerca. Il tema scelto è “Il rapporto interno-esterno a Venezia,” analizzato attraverso la creazione di disegni sperimentali. Per raggiungere questo obiettivo, sono state considerate tre diverse discipline di indagine: 1. Cinema: “Morte a Venezia” di Luchino Visconti, 2. Pittura: Tancredi, Bellini, Zecchin e 3. Il libro di disegni architettonici: “Studi per una Operante Storia Urbana di Venezia” di Saverio Muratori. Queste tre discipline offrono prospettive uniche e servono da lente attraverso cui la città viene riesaminata e riletta: Venezia. I disegni sperimentali creati sulla base di queste discipline sono soggettivi e unici per l’autore, ma possiedono un proprio linguaggio e una propria logica interna.
Come seconda fase del progetto architettonico, è stata derivata una regola specifica: un nuovo “alfabeto” è ottenuto dai disegni sperimentali della prima fase, utilizzando una sintassi tratta dal “Dictionnaire Amoureux de Venise” di Philippe Sollers. Per creare possibili scenari spaziali architettonici, vengono inoltre utilizzate le tecniche di montaggio e collage per proiettare elementi bidimensionali nello spazio tridimensionale, incorporando lo stesso mondo visivo e concettuale dei disegni di Muratori e del film di Visconti. Come parte di questo esperimento progettuale, “la griglia” viene introdotta come strumento e posizionata sul sito sperimentale scelto, l’isola di San Giacomo di Paludo nella laguna veneziana. Come risultato di questa intera catena, il mondo tridimensionale viene costruito con infinite possibilità, attraverso le visioni di Visconti, Muratori e dell’Autore. Come risultato finale della ricerca complessiva, viene realizzato un unico progetto architettonico specifico tra queste possibilità infinite.This thesis is centered around an experimental approach that forms the foundation for both the representation techniques and the architectural project explored in this research. The selected research theme is “Inside-Outside Relationship in Venice,” explored through the creation of experimental drawings. To achieve this, three different disciplines of inquiry were considered: 1. Film: Death in Venice by Luchino Visconti, 2. Paintings: Tancredi, Bellini, Zecchin and 3. The book of Architectural Drawings: “Studi per una Operante Storia Urbana di Venezia” by Saverio Muratori. These three disciplines offer unique perspectives and serve as a lens through which the city is re-examined and re-read: Venice. The experimental drawings created based on the disciplines are subjective and unique to the author, yet they possess their own internal language and logic.
As a second phase for the architectural project, a certain rule was derived; a new “alphabet” is obtained upon the experimental drawings from the first phase with a syntax of the “Dictionnaire Amoureux de Venise” by Philippe Sollers. For creating possible architectural space scenarios, additionally, the techniques of montage and collage are used to project two-dimensional elements into three-dimensional space, incorporating the same visual and conceptual world as Muratori’s drawings and Visconti’s film. As part of this design experiment, “the grid” is introduced as a tool and placed on the chosen experimental site, which is the Island of San Giacomo di Paludo in the Venetian lagoon. As a result of this entire chain, the three-dimensional world is thus constructed with countless possibilities, with the visions of Visconti, Muratori, and the Author. As the final result of the overall research, just one specific architectural project is carried out, among these infinite possibilities
