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2018

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Regression Models For Analyzing Clustered Multinomial And Continuous Outcomes Under The Assumption Of Exchangeability, Peter Ogutu Ngutu Jan 2018

Regression Models For Analyzing Clustered Multinomial And Continuous Outcomes Under The Assumption Of Exchangeability, Peter Ogutu Ngutu

Electronic Theses and Dissertations Archive

We derive an expression for the joint distribution of exchangeable multinomial randomvariables and continous random variables for the purpose of analyzing clusteredmultinomial and continous data. In the past such clustered discrete and continous datacould be analyzed with the use of quasi-likelihood procedures and generalized estimatingequations to estimate marginal mean response parameters. Recently, the idea ofexchangeability has been introduced to handle such data but research has focusedprimarily on analysis of clustered binary and continous outcomes. In applications to areassuch as developmental toxicity studies, where discrete and contionus measures arerecorded on each fetus, the discrete data may not necessarily be binary. For …


First Record Of The Yellowfin Soldierfish, Myripristis Chryseresjordan & Evermann, 1903, In The Easter Island Ecoregion, Erin E. Easton, Javier Sellanes, Matthias Gorny Jan 2018

First Record Of The Yellowfin Soldierfish, Myripristis Chryseresjordan & Evermann, 1903, In The Easter Island Ecoregion, Erin E. Easton, Javier Sellanes, Matthias Gorny

School of Earth, Environmental, & Marine Sciences Faculty Publications

Myripristis chryseres Jordan & Evermann, 1903, is recorded for the first time in the Easter Island Ecoregion. Two specimens were observed swimming along a rock cliff and entering a cavern at ∼163 m depth near the peak of Pukao seamount, located ∼85 km (46 nm) west of Easter Island. This report expands the geographic range of M. chryseres eastward by ∼3,800 km and is the first report of the species for the eastern Pacific. It is unclear whether this new record is indicative of a relatively recent range expansion or a lack of visual surveys in the region, which …


Preliminary Multivariate Comparison Of Coral Assemblages On Carbonate Banks In The Western Gulf Of Mexico, Rebekah E. Rodriguez, Erin E. Easton, Thomas C. Shirley, John W. Tunnell, David Hicks Jan 2018

Preliminary Multivariate Comparison Of Coral Assemblages On Carbonate Banks In The Western Gulf Of Mexico, Rebekah E. Rodriguez, Erin E. Easton, Thomas C. Shirley, John W. Tunnell, David Hicks

School of Earth, Environmental, & Marine Sciences Faculty Publications

Hermatypic corals flourished on reefs in the Gulf of Mexico (GOM) in the late Pleistocene and early Holocene. Today, many of these relict reefs are mesophotic banks that have unique coral assemblages and provide critical habitat; however, the South Texas Banks (STB) lack quantitative surveys. Therefore, we used a remotely operated vehicle to conduct quantitative surveys of 5 banks: Baker, Aransas, Dream, Blackfish Ridge, and Harte. Coral communities, based on estimated coral densities (colonies/m2), significantly differed among banks for terraces, slopes, and overall (combined terrace and slope) communities for most banks examined. Within banks, terrace and slope communities significantly differed …


Presenting A Hybrid Processing Mining Framework For Automated Simulation Model Generation, Susan Mckeever, Mohammad Messabah Jan 2018

Presenting A Hybrid Processing Mining Framework For Automated Simulation Model Generation, Susan Mckeever, Mohammad Messabah

Conference papers

Recent advances in information technology systems have enabled organizations to store tremendous amounts of business process data. Process mining offers a range of algorithms and methods to analyze and extract metadata for these processes. This paper presents a novel approach to the hybridization of process mining techniques with business process modelling and simulation methods. We present a generic automated end-to-end simulation framework that produces unbiased simulation models using system event logs. A conceptual model and various meta-data are derived from the logs and used to generate the simulation model. We demonstrate the efficacy of our framework using a business process …


Ball Family Papers - Accession 774, Ball Family Jan 2018

Ball Family Papers - Accession 774, Ball Family

Manuscript Collection

The Ball Family Papers consists of 52 microfiche that covers the operation of several plantations on the Cooper River in the Berkeley County area in South Carolina. The Ball Family Papers consist of correspondence, legal documents, wills and estate papers, plantation papers and slave records, accounts, receipts, genealogical material, plats, and other items pertaining to the Ball family and related families. The collection also includes the papers of John Ball (1760-1817), William James Ball (1787-1808), Ann Simons Ball (1776-1840), John Ball (1782-1834), and William James Ball (1821-1891), as well as the journal (1715-1716) of Captain George Chicken (d. 1727). Also …


Pathways To The Cosmos:The Alignment Of Megalithic Tombs In Ireland And Atlantic Europe, Frank Prendergast, Gabriel Cooney Jan 2018

Pathways To The Cosmos:The Alignment Of Megalithic Tombs In Ireland And Atlantic Europe, Frank Prendergast, Gabriel Cooney

Articles

Gabriel Cooney and Frank Prendergast present the context of and outline the approach to this one-day conference organised by Archaeology Ireland on behalf of the National Monuments Service at the Department of Culture, Heritage and the Gaeltacht and the Office of Public Works to mark the European Year of Cultural Heritage 2018. The event will take place at Dublin Castle on 15 September 2018.


Survivability Strategies For Emerging Wireless Networks With Data Mining Techniques: A Case Study With Netlogo And Rapidminer, Ivan Garcia-Magarino, Geraldine Gray, Raquel Lacuesta, Jaime Lloret Jan 2018

Survivability Strategies For Emerging Wireless Networks With Data Mining Techniques: A Case Study With Netlogo And Rapidminer, Ivan Garcia-Magarino, Geraldine Gray, Raquel Lacuesta, Jaime Lloret

Articles

Emerging wireless networks have brought Internet and communications to more users and areas. Some of the most relevant emerging wireless technologies are Worldwide Interoperability for Microwave Access, Long-Term Evolution Advanced, and ad hoc and mesh networks. An open challenge is to ensure the reliability and robustness of these networks when individual components fail. The survivability and performance of these networks can be especially relevant when emergencies arise in rural areas, for example supporting communications during a medical emergency. This can be done by anticipating failures and finding alternative solutions. This paper proposes using big data analytics techniques, such as decision …


Generating Diverse And Meaningful Captions: Unsupervised Specificity Optimization For Image Captioning, Annika Lindh, Robert J. Ross, Abhijit Mahalunkar, Giancarlo Salton, John D. Kelleher Jan 2018

Generating Diverse And Meaningful Captions: Unsupervised Specificity Optimization For Image Captioning, Annika Lindh, Robert J. Ross, Abhijit Mahalunkar, Giancarlo Salton, John D. Kelleher

Conference papers

Image Captioning is a task that requires models to acquire a multi-modal understanding of the world and to express this understanding in natural language text. While the state-of-the-art for this task has rapidly improved in terms of n-gram metrics, these models tend to output the same generic captions for similar images. In this work, we address this limitation and train a model that generates more diverse and specific captions through an unsupervised training approach that incorporates a learning signal from an Image Retrieval model. We summarize previous results and improve the state-of-the-art on caption diversity and novelty.

We make our …


On The Structure Of Dense Graphs, And Other Extremal Problems, Richard Snyder Jan 2018

On The Structure Of Dense Graphs, And Other Extremal Problems, Richard Snyder

Electronic Theses and Dissertations Archive

Extremal combinatorics is an area of mathematics populated by problems that are easy to state, yet often difficult to resolve. The typical question in this field is the following: What is the maximum or minimum size of a collection of finite objects (e.g., graphs, finite families of sets) subject to some set of constraints? Despite its apparent simplicity, this question has led to a rather rich body of work. This dissertation consists of several new results in this field.The first two chapters concern structural results for dense graphs, thus justifying the first part of my title. In the first chapter, …


Attaining Scientific Literacy Through A Rhetoric Of Science Composition Pedagogy, Stephen C. Smith Jan 2018

Attaining Scientific Literacy Through A Rhetoric Of Science Composition Pedagogy, Stephen C. Smith

Electronic Theses and Dissertations Archive

For the past sixty years, acquiring scientific literacy has proven to be a daunting task in education, especially for undergraduate nonscience majors. Although some education scholars have recognized the importance and use of arguments to teach science, these pedagogical practices often are aimed at primary school children rather than college students or involve reporting science experiments rather than actually studying or constructing arguments about issues related to science.However, in this dissertation, I contend that educators often neglect a more available tool that not only examines arguments concerning scientific issues but also demonstrates the very heart of scientific literacy: critical thinking. …


Principals Attitudes Toward The Inclusion Of Students With Disabilities In The General Education Classroom, Kendale Marquis White Jan 2018

Principals Attitudes Toward The Inclusion Of Students With Disabilities In The General Education Classroom, Kendale Marquis White

Electronic Theses and Dissertations Archive

The purpose of this study was to examine the attitudes of principals as it relates to the inclusion of students with disabilities in the general education setting. This study replicates and extends research in relation to principals and their attitudes toward inclusion. In addition, the researcher determined whether a relationship, if any, exists between demographic variables and their attitudes regarding the most appropriate placement for students with disabilities. A self-reporting survey entitled the Principals and Inclusion Survey was used to collect the data from 105 principals. Results revealed principals training and experience were limited, principals supported inclusive placements for students …


Statistical Analysis Of Seismicity Catalog Of Alaska: The Mysteries Of The Timeseries, Shima Azizzadehroodpish Jan 2018

Statistical Analysis Of Seismicity Catalog Of Alaska: The Mysteries Of The Timeseries, Shima Azizzadehroodpish

Electronic Theses and Dissertations Archive

Abstract:This dissertation presents the results of applying three independent statistical techniques on the seismic catalog of Alaska and Aleutian subduction zone. I perform Visibility Graph Analysis and Multifractal Detrended Fluctuation Analysis respectively on the seismic catalogs of several defined seismogenic zones in surface and depth. Forecasting earthquake hazard is based on the assumption that the Gutenberg-Richter relation represents the size distribution of future earthquakes and we show that the series produced by these methods have properties with close correlation with the b-value of the Gutenberg-Richter law. Visibility graph analysis basically maps a time series into the networks of nodes and …


Automated Artifact Removal And Detection Of Mild Cognitive Impairment From Single Channel Electroencephalography Signals For Real-Time Implementations On Wearables, Saleha Khatun Jan 2018

Automated Artifact Removal And Detection Of Mild Cognitive Impairment From Single Channel Electroencephalography Signals For Real-Time Implementations On Wearables, Saleha Khatun

Electronic Theses and Dissertations Archive

Electroencephalogram (EEG) is a technique for recording asynchronous activation of neuronal firing inside the brain with non-invasive scalp electrodes. EEG signal is well studied to evaluate the cognitive state, detect brain diseases such as epilepsy, dementia, coma, autism spectral disorder (ASD), etc. In this dissertation, the EEG signal is studied for the early detection of the Mild Cognitive Impairment (MCI). MCI is the preliminary stage of Dementia that may ultimately lead to Alzheimers disease (AD) in the elderly people. Our goal is to develop a minimalistic MCI detection system that could be integrated to the wearable sensors. This contribution has …


Middle School Teachers Perceptions Of The Factors That Support Or Impede The Inclusion Of Reading Strategies Into Classroom Instruction, Angelica S. Burks-Henley Jan 2018

Middle School Teachers Perceptions Of The Factors That Support Or Impede The Inclusion Of Reading Strategies Into Classroom Instruction, Angelica S. Burks-Henley

Electronic Theses and Dissertations Archive

This interpretive case study took place in an urban middle school where content area math and science teachers engaged in content area reading instruction designed to promote students reading development in their content area classes. Participants included eight teachers across grade levels six, seven and eight. Teachers participated in a Background Information Questionnaire designed to obtain their perceptions, literacy beliefs and literacy practices; focus group interviews created to explore their perceptions related to the key themes in the literature regarding content area reading instruction; structured one-on-one interviews to corroborate researcher interpretations of the initial data analysis and to collect individual …


Understanding Why Women Stay: Examining Persistence Factors Of Women Majoring In Science And Technology Programs In Public Ethiopian Universities Using A Mixed Methods Design, Meseret Hailu Jan 2018

Understanding Why Women Stay: Examining Persistence Factors Of Women Majoring In Science And Technology Programs In Public Ethiopian Universities Using A Mixed Methods Design, Meseret Hailu

Electronic Theses and Dissertations

Amongst African nations, Ethiopia is a unique case in many respects. The country has the second largest population on the continent, is currently experiencing an economic boom, and is a relatively stable nation in the geopolitically volatile "Horn of Africa" region. In the past two decades, the higher education sector in Ethiopia has experienced rapid growth, as evidenced by an increase in both student enrollment and the number of universities. Amongst the various types of higher education institutions, public universities are especially important because they receive the greatest financial support from the Ministry of Education. Moreover, science and technology programs …


Investigating Inquiry-Based Learning: Teachers Perspectives At A K-12 School, Rezaul Chowdhury Jan 2018

Investigating Inquiry-Based Learning: Teachers Perspectives At A K-12 School, Rezaul Chowdhury

Electronic Theses and Dissertations Archive

Inquiry-based learning (IBL) is receiving a lot of attention and consideration as a modern instructional method. Teaching strategies that actively involve students in the learning process through inquiry instructions are more likely to increase conceptual understanding than of strategies that rely on more passive techniques. The purpose of this study is to better understand how a selected group of five teachers perceive and practice inquiry-based learning (IBL) as an instructional method in their classrooms across all disciplines at one K-12 school. This study employed a case study methodology to better understand teachers perceptions, practices, and technology integration, while using IBL …


Commencement 2018 (Program And Video), Illinois Wesleyan University Jan 2018

Commencement 2018 (Program And Video), Illinois Wesleyan University

Commencement Ceremonies

The recording embedded here was posted to YouTube by University Communications without the remarks of Kirk S. Schroeder '84, honorary doctorate recipient. A recording of that portion of the ceremony is available in the University Archives.


Earthquake Early Warning System (Eews) For The New Madrid Seismic Zone, Luke Philip Ogweno Jan 2018

Earthquake Early Warning System (Eews) For The New Madrid Seismic Zone, Luke Philip Ogweno

Electronic Theses and Dissertations Archive

Part 1: Research in the last decade on Earthquake Early Warning Systems (EEWSs) has undergone rapid development in terms of theoretical and methodological advances in real time data analysis, improved telemetry, and computer technology and is becoming a useful tool for practical real time seismic hazard mitigation. The main focus of this study is to undertake a feasibility study of an EEWS for the New Madrid Seismic Zone (NMSZ) from the standpoint of source location. Magnitude determination is addressed in a separate paper. The NMSZ covers a wide area with several heavily populated cities, vital infrastructures, and facilities located within …


Decoupled, Linear, And Energy Stable Finite Element Method For The Cahn-Hilliard-Navier-Stokes-Darcy Phase Field Model, Yali Gao, Xiaoming He, Liquan Mei, Xiaofeng Yang Jan 2018

Decoupled, Linear, And Energy Stable Finite Element Method For The Cahn-Hilliard-Navier-Stokes-Darcy Phase Field Model, Yali Gao, Xiaoming He, Liquan Mei, Xiaofeng Yang

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we consider the numerical approximation for a phase field model of the coupled two-phase free flow and two-phase porous media flow. This model consists of Cahn—Hilliard—Navier—Stokes equations in the free flow region and Cahn—Hilliard—Darcy equations in the porous media region that are coupled by seven interface conditions. The coupled system is decoupled based on the interface conditions and the solution values on the interface from the previous time step. A fully discretized scheme with finite elements for the spatial discretization is developed to solve the decoupled system. In order to deal with the difficulties arising from the …


Failure Of The Alexander Dam Embankment And Reconstruction Using Drainage Mitigation On Kauai, Hawaii, 1930-1932, Kerry D. Cato, J. David Rogers Jan 2018

Failure Of The Alexander Dam Embankment And Reconstruction Using Drainage Mitigation On Kauai, Hawaii, 1930-1932, Kerry D. Cato, J. David Rogers

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Alexander Dam is a hydraulic fill earth dam and the second-highest embankment dam in Hawaii, having been built in 1929-1932 on the south side of the Hawaiian island of Kauai to provide irrigation for McBryde Sugar Company Ltd. It was constructed across Wahiawa Stream mauka (Hawaiian for "stream that comes from the mountains," literally "toward the mountains"), upstream of Kalaheo, to store 800 million gallons (5 million m3) of water to irrigate sugarcane fields. The embankment dam was intended to have a maximum height of 125 ft (38 m), a crest length of 620 ft (189 m), and a maximum …


An Integrated Method For Forecasting Well Deliverability In Gas Condensate Reservoirs With Bottom Aquifer Drive, Abdulaziz Ellafi, Ralph E. Flori, Shari Dunn-Norman Jan 2018

An Integrated Method For Forecasting Well Deliverability In Gas Condensate Reservoirs With Bottom Aquifer Drive, Abdulaziz Ellafi, Ralph E. Flori, Shari Dunn-Norman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Gas condensate reservoirs constitute a significant portion of global hydrocarbon reserves. In these reservoirs, liquids develop in the pore space once bottomhole pressure falls below dew point. This results in the formation of a liquid bank near the wellbore region which decreases gas mobility, which then reduces gas inflow. In such complex reservoirs, it is important to correctly describe PVT impacts, adjustments to well test analysis and inflow performance, and then combine all effects in the reservoir analysis. The literature contains many references to individual adjustments of PVT analysis, well testing, or inflow performance for gas condensate reservoirs, but few …


Testing And Evaluation Of Shale Stability For Zubair Shale Formation, Ahmed K. Abbas, Ralph E. Flori, Ahmed Al-Anssari, Mortadha Alsaba Jan 2018

Testing And Evaluation Of Shale Stability For Zubair Shale Formation, Ahmed K. Abbas, Ralph E. Flori, Ahmed Al-Anssari, Mortadha Alsaba

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Zubair Formation consists of approximately 55% shale, which causes almost 70% of wellbore problems due to incompatibilities of drilling fluids and shale formations. The most common and effective solution to shale instability is through the design and selection of drilling fluids. Understanding the interaction between drilling fluids and shale has been a challenge due to the complexity of both physical and chemical variations in shale formations. This paper presents some of the important laboratory and well-site testing techniques that are often used by mud engineers for characterizing and remediating drilling fluids and shale interaction. Well-preserved shale samples were analyzed to …


Advanced Ion Management To Improve Oil Recovery In Oil-Wet Carbonate-Sandstone Composite Reservoirs, Ali K. Alhuraishawy, Baojun Bai, Mingzhen Wei, Waleed H. Al-Bazzaz Jan 2018

Advanced Ion Management To Improve Oil Recovery In Oil-Wet Carbonate-Sandstone Composite Reservoirs, Ali K. Alhuraishawy, Baojun Bai, Mingzhen Wei, Waleed H. Al-Bazzaz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Waterflooding with different ionic composition called advanced ion management which play a role with ionic composition of injected water to enhance the oil production. In the last decade, many studies pointed out that the composition of injected water could changes rock wettability during waterflooding. The main purpose of this study is to evaluate the effects of SO4 and low salinity water on improving oil recovery in oil-wet carbonate reservoirs. Sulfate ion concentration, low salinity water, rock composition, porosity, and permeability were examined using a designed model. Typical seawater, increase SO4, two and three times in the seawater, and …


Miscible Gases Based Eor In Unconventional Liquids Rich Reservoirs: What We Can Learn, Dheiaa Alfarge, Mortadha Alsaba, Mingzhen Wei, Baojun Bai Jan 2018

Miscible Gases Based Eor In Unconventional Liquids Rich Reservoirs: What We Can Learn, Dheiaa Alfarge, Mortadha Alsaba, Mingzhen Wei, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Over the last decade, Unconventional Liquids Rich Reservoirs (ULR) have become the main target for oil and gas investors as conventional formations started to deplete and diminish in numbers. These unconventional plays have a huge oil reserve; however, the primary oil recovery factor is predicted to be less than 10%. Unconventional Improved Oil Recovery (UIOR) techniques are still a new concept in the oil industry since there is no commercial project reported for any IOR technique yet. Miscible gas based EOR technique might be the most potential strategy to improve oil recovery in such complex plays. In this study, a …


New Insights Of Low Salinity Water Flooding In Low Permeability-Low Porosity Clay Rich Sandstone Reservoir, Ali K. Alhuraishawy, Baojun Bai, Mingzhen Wei, Waleed H. Al-Bazzaz Jan 2018

New Insights Of Low Salinity Water Flooding In Low Permeability-Low Porosity Clay Rich Sandstone Reservoir, Ali K. Alhuraishawy, Baojun Bai, Mingzhen Wei, Waleed H. Al-Bazzaz

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

One of the EOR technologies is low-salinity water flooding (LSWF) is an EOR method that operates at a lower cost than other EOR methods, which makes it a preferred area of interest for oil industry economists, who continue to call for EOR costs to come down. The aim is to minimize the possible cost to recover as much oil as possible. The performance of low salinity waterflooding in decreasing residual oil saturation in low permeability-porosity clay-rich sandstone reservoir. Porosity test, core flooding test, XRD and scanning electron microscopy (SEM) tests were achieved in this study. Salinity effect on the porosity, …


Application Of Integrated Reservoir Geomechanics For Well Planning Of High-Angled Wells In A Mature Oil Field, Ahmed K. Abbas, Ralph E. Flori, Yousif M.B. Al-Asadi, Mortadha Alsaba, Nasser A. Al-Hamad Jan 2018

Application Of Integrated Reservoir Geomechanics For Well Planning Of High-Angled Wells In A Mature Oil Field, Ahmed K. Abbas, Ralph E. Flori, Yousif M.B. Al-Asadi, Mortadha Alsaba, Nasser A. Al-Hamad

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Zubair oil reservoir has a significant potential to contribute to the petroleum supply in Iraq. Drilling highly deviated wells is a commonly used approach to enhance the production in mature fields. Drilling these wells in the Zubair Formation has been a challenge due to severe wellbore instability issues. This study presents how integrated reservoir geomechanics was used for efficient well planning and safe drilling of nearly horizontal wells (75° Inclination) through Zubair depleted sandstone oil reservoir. In this study, an integrated workflow was implemented mainly to build a geomechanical model using offset well data. The in-situ principal stresses and their …


Learning From Experience: An Automatic Ph Neutralization System Using Hybrid Fuzzy System And Neural Network, Ethar H.K. Alkamil, Seaar Al-Dabooni, Ahmed K. Abbas, Ralph Flori, Donald C. Wunsch Jan 2018

Learning From Experience: An Automatic Ph Neutralization System Using Hybrid Fuzzy System And Neural Network, Ethar H.K. Alkamil, Seaar Al-Dabooni, Ahmed K. Abbas, Ralph Flori, Donald C. Wunsch

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

In oil and gas industry, the pH level is one of the most important indicators of mud contamination while drilling. Although the process has simple components, the pH neutralization process is complicated in the mud circulation system. This difficulty is due to the high nonlinearity of the process. In this paper, the fuzzy neural network (FNN) is integrated to the fuzzy logic controller (FLC) to create a system which identifies pH fluctuation into a drilling mud system, assesses and signals its severity. And then, it automatically actuates a chemical treating fluids valve (CTFV), such as Caustic Soda (CS), for neutralizing …


Using Managed Pressure Drilling To Reduce Stuck Pipe Problem, Ethar H.K. Alkamil, Husam R. Abbood, Ralph E. Flori, George Medley, Sagar Nauduri, Mortadha Alsaba Jan 2018

Using Managed Pressure Drilling To Reduce Stuck Pipe Problem, Ethar H.K. Alkamil, Husam R. Abbood, Ralph E. Flori, George Medley, Sagar Nauduri, Mortadha Alsaba

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Differences between mud pressure in a wellbore and pore pressure in high permeability rocks can lead to differential sticking, particularly when drilling deviated wells and encountering mud losses. Several solutions, all challenging, can be used to address this problem, where the conventional mitigation method of managing the mud weight (MW) is often used. However, managed pressure drilling (MPD) offers a promising solution with a positive risk-adjusted cost and other benefits. Wells in the E oilfield in southern Iraq are typically drilled overbalanced and therefore often experience a high percentage of non-productive time (NPT) due to differential sticking. This study evaluates …


Computational Modeling Of Heat Transport And Volatile Extraction From Asteroid Materials, Joel C. Sercel, Mark A. Crawford, Christopher Dreyer, Egboche Unobe, Robert Jedicke, Stanley Love, Leslie S. Gertsch Jan 2018

Computational Modeling Of Heat Transport And Volatile Extraction From Asteroid Materials, Joel C. Sercel, Mark A. Crawford, Christopher Dreyer, Egboche Unobe, Robert Jedicke, Stanley Love, Leslie S. Gertsch

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

This paper presents the results of a program of computational modeling focused on elucidating the physics and chemical processes associated with the extraction of volatile materials from asteroid feedstocks with an eye toward use of the extracted materials for propulsion, radiation shielding, and replenishment of mission consumables. We present a math model of conductive heat transport, chemical processes, and gas escape by Darcian diffusion. Chemical processes in the model include pyrolysis of organic chemical constituents and thermal dehydration and decarbonization of hydrates and carbonates. The model is implemented in a spherical finite difference computational engine that predicts time histories of …


A Novel Ultra-Low Interfacial Tension Nanofluid For Enhanced Oil Recovery In Super-Low Permeability Reservoirs, Derong Xu, Baojun Bai, Ziyu Meng, Qiong Zhou, Zhe Li, Yao Lu, Hairong Wu, Jirui Hou, Wanli Kang Jan 2018

A Novel Ultra-Low Interfacial Tension Nanofluid For Enhanced Oil Recovery In Super-Low Permeability Reservoirs, Derong Xu, Baojun Bai, Ziyu Meng, Qiong Zhou, Zhe Li, Yao Lu, Hairong Wu, Jirui Hou, Wanli Kang

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The exploration and development of super-low permeability reservoirs have become a global focus in recent years. However, conventional flooding systems commonly face problems of high injection pressure and poor displacement efficiency in super-low permeability reservoirs. Thus, it is imperative to find new flooding agents that tackle such problems. In this study, a novel ultra-low interfacial tension (IFT) nanofluid was formulated, consisting of surfactants to achieve ultra-low IFT and silica nanoparticles to reduce injection pressure. The compatibility test between the surfactants and silica nanoparticles in 10,000 mg/L NaCl solution at 90 °C was conducted to ensure their adaption to harsh reservoir …