Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Physical Sciences and Mathematics (1401)
- Chemistry (456)
- Engineering (431)
- Education (195)
- Applied Mathematics (188)
-
- Social and Behavioral Sciences (146)
- Computer Sciences (145)
- Oceanography and Atmospheric Sciences and Meteorology (135)
- Environmental Sciences (115)
- Physics (111)
- Earth Sciences (109)
- Civil and Environmental Engineering (108)
- Chemical Engineering (102)
- Arts and Humanities (94)
- Life Sciences (86)
- Electrical and Computer Engineering (83)
- Mathematics (75)
- Mechanical Engineering (66)
- Business (61)
- Music (58)
- Psychology (57)
- Engineering Science and Materials (48)
- Petroleum Engineering (45)
- Human Resources Management (44)
- Analytical Chemistry (38)
- Curriculum and Instruction (37)
- Quantum Physics (36)
- Physical Chemistry (34)
- Organic Chemistry (31)
- Astrophysics and Astronomy (29)
- Keyword
-
- Louisiana (25)
- Machine learning (25)
- Optimization (22)
- Microfluidics (21)
- Nanoparticles (21)
-
- Synthesis (20)
- Molecular dynamics (17)
- Gulf of Mexico (14)
- Machine Learning (14)
- Modeling (14)
- Gravitational waves (13)
- Mass spectrometry (13)
- Simulation (13)
- GUMBOS (12)
- LIGO (12)
- Quantum (12)
- Retention (12)
- Catalysis (11)
- Fluorescence (11)
- Knot theory (11)
- Optics (11)
- Spectroscopy (11)
- Wetlands (11)
- Atomic force microscopy (10)
- Capillary electrophoresis (10)
- Hurricane (10)
- Intermetallics (10)
- NMR (10)
- Remote sensing (10)
- Cancer (9)
Articles 2221 - 2250 of 2326
Full-Text Articles in Entire DC Network
The Impact Of Louisiana's School And District Accountability System On Students' Performance On The State Mandated Criterion Referenced Test, Linda B. Tolbert
The Impact Of Louisiana's School And District Accountability System On Students' Performance On The State Mandated Criterion Referenced Test, Linda B. Tolbert
LSU Doctoral Dissertations
This study is aimed at determining the impact of Louisiana’s School and District Accountability System on students’ performance on the state mandated criterion-referenced test (LEAP 21). The study was designed to determine the extent to which teachers in Title I schools in a large urban district in southwest Louisiana have turned to instructionally unsound practices in response to a high-stakes accountability system. The specific objectives addressed in this study were to: 1) Explore if test scores have changed beyond what would be expected given the cohort design of the accountability model. 2) Explore if test scores have changed and determine …
Design And Synthesis Of Handles For Solid-Phase Peptide Synthesis And Convergent Peptide Synthesis, Jose Giraldes
Design And Synthesis Of Handles For Solid-Phase Peptide Synthesis And Convergent Peptide Synthesis, Jose Giraldes
LSU Doctoral Dissertations
The recent popularity of methods for solid-phase peptide synthesis that use the 9-fluorenylmethyloxycarbonyl (Fmoc) group for Nα-amino protection has created a need for compatible anchoring linkages and handles. In an effort to develop mild new methods for use in solid-phase peptide synthesis (SPPS), a new ferrocene containing linker or “handle”, the 1’1-ferrocenyl carboxaldehyde handle was designed, synthesized, characterized and tested. This linker is analogous to those commercially available and developed by Barany. The ferrocenyl amine linker(FAL) releases C-terminal peptide amides upon acidolysis. Since the FAL handle is acid labile it is compatible with Fmoc and Nα-dithiasuccinoyl …
Characterization Of Native And Bypass Human Coronary Artery Plaque Deposits From The Same Heart: Investigation Of The Chemical Form Of Calcium In Human Coronary Artery Plaque Deposits, Serigne Thiam
LSU Doctoral Dissertations
Gradual deposits of lipids, proteins, and calcium on the coronary arterial walls cause atherosclerosis, leading to blockage of the blood flow and possible heart attack. Despite many studies, the mechanism underlying these processes remains unclear. In this research, differences between native and bypass plaque deposits from the same heart were examined. In addition, the crystalline and the amorphous plaques within these native and bypass vessels were characterized. The techniques used to characterize the deposits included inductively coupled plasma mass spectrometry (ICPMS), solid-state nuclear magnetic resonance (NMR), high performance liquid chromatography (HPLC), etc. The results from the ICPMS technique showed that …
Synchrotron Radiation As A Probe Of Chemical Information Using Novel Experimental Configurations, George Farquar
Synchrotron Radiation As A Probe Of Chemical Information Using Novel Experimental Configurations, George Farquar
LSU Doctoral Dissertations
Determination of chemical information with synchrotron radiation is an area of great scientific interest, and expanding the range of available techniques is the topic of this dissertation. The experimental methods described herein allows for a significant advancement of the availability of subtle chemical information. This dissertation uses ionizing radiation to study three chemical systems. First, the l=3 shape resonance in CO is investigated using a cryogenically cooled gas jet. Shape resonant effects have been studied for many years. Previously, this was accomplished on the vibrational structure of molecules with a limited ability to determine the rotational substructure effects. A dramatic …
Uncovering Strata: An Investigation Into The Graphic Innovations Of Geologist Henry T. De La Beche, Renee M. Clary
Uncovering Strata: An Investigation Into The Graphic Innovations Of Geologist Henry T. De La Beche, Renee M. Clary
LSU Doctoral Dissertations
An historical investigation into the types of illustrations in the Golden Age of Geology (1788-1840) revealed the nature and progression of graphic representation at the dawning of geology as a science. Exhaustive sampling of geology texts published in the period of focus proceeded until saturation was achieved. Qualitative analysis and evaluation of early illustrations were accomplished with Edward R. Tufte's theory of graphic design. Hypothesis testing around a correlation coefficient revealed significance at the 99% confidence level for relationships between publication year and number of included graphics, and publication year and the graphic density of texts. Henry T. De la …
Atomic And Electronic Structure Of Bulk Intermetallic And Heteroepitaxially Grown Surface Alloys, Orhan Kizilkaya
Atomic And Electronic Structure Of Bulk Intermetallic And Heteroepitaxially Grown Surface Alloys, Orhan Kizilkaya
LSU Doctoral Dissertations
It has been well documented that the surfaces of solids may differ from their bulk counterpart. The symmetry that a bulk possesses is broken at the surface. Due to this broken symmetry in the reduced dimension of the surface, the energetic of the surface also differs from the bulk counterpart. Reconstruction, charge redistribution, and surface alloying are phenomena that minimize the surface free energy. Surface properties of scientifically and technologically important bimetallic systems are the main focus of this dissertation. Specifically, surfaces of bulk alloy or heteroepitaxially grown metal-on-metal systems have been investigated primarily with two indispensable surface techniques, scanning …
Self-Efficacy, Motivation, And Outcome Expectation Correlates Of College Students' Intention Certainty, Carol Couvillion Landry
Self-Efficacy, Motivation, And Outcome Expectation Correlates Of College Students' Intention Certainty, Carol Couvillion Landry
LSU Doctoral Dissertations
This study explored relationships between Self-Efficacy, Motivation, and Outcome Expectations and Intention Certainty. Intention Certainty is a new variable created for this study and comprised of existing conceptions of intention and decision certainty. The purpose of this study was fourfold. This study attempted to expand our understanding of the college retention dropout issue by exploring relationships between psychologically rich variables. Second, this study provided information considered useful for framing future research on retention from a different perspective that focuses on characteristics of individuals who stay, rather than those who leave higher education with the consideration of psychological constructs. Further, this …
Diffusion Of A Rodlike Virus In Complex Solutions, Randall Charles Cush
Diffusion Of A Rodlike Virus In Complex Solutions, Randall Charles Cush
LSU Doctoral Dissertations
Entanglement phenomena in concentrated polymer solutions remain an interesting and challenging problem. It is still unclear how entanglement onset affects polymer chain motion at small distance scales. One way to study such motion is to follow the diffusion of a probe particle while increasing the concentration of the polymer. Many such studies have been done using probes ranging from linear and star polymers to various colloidal particles; however, relatively few studies have used rodlike probes. Rodlike probes are potentially more interesting due to the added information that may be gained by following rotational as well as translational diffusion. The anisotropic …
Design Of Optimal Equalizers And Precoders For Mimo Channels, Lijuan Li
Design Of Optimal Equalizers And Precoders For Mimo Channels, Lijuan Li
LSU Doctoral Dissertations
Channel equalization has been extensively studied as a method of combating ISI and ICI for high speed MIMO data communication systems. This dissertation focuses on optimal channel equalization in the presence of non-white observation noises with unknown PSD but bounded power-norm. A worst-case approach to optimal design of channel equalizers leads to an equivalent optimal H-infinity filtering problem for the MIMO communication systems. An explicit design algorithm is derived which not only achieves the zero-forcing (ZF) condition, but also minimizes the RMS error between the transmitted symbols and the received symbols. The second part of this dissertation investigates the design …
Massively Parallel Molecular Dynamics Simulations Of Crack-Front Dynamics And Morphology In Amorphous Nanostructured Silica, Cindy Lynn Rountree
Massively Parallel Molecular Dynamics Simulations Of Crack-Front Dynamics And Morphology In Amorphous Nanostructured Silica, Cindy Lynn Rountree
LSU Doctoral Dissertations
Atomistic aspects of dynamic fracture in amorphous and nanostructured silica are herein studied via Molecular dynamics (MD) simulations, ranging from a million to 113 million atom system. The MD simulations were performed on massivelly parallel computers using highly efficient multi-resolution algorithms. Crack propagation in these systems is accompanied by nucleation and growth of nanometer scale cavities up to 20 nm ahead of the crack front. Cavities coalesce and merge with the advancing crack to cause mechanical failure. Recent AFM studies in silica glasses confirm this scenario of fracture [1]. The morphology of the fracture surfaces is studied by calculating the …
The Extinction Properties Of Reddened Galactic Ob Sightlines, Lynne Angela Valencic
The Extinction Properties Of Reddened Galactic Ob Sightlines, Lynne Angela Valencic
LSU Doctoral Dissertations
A solid understanding of dust grains and their extinction properties is needed to better remove the effects of extinction from data and to comprehend the nature of the processes which modify grains. This requires a large sample of Galactic sightlines, extending far beyond the solar neighborhood, sampling not only a large volume of space but also a wide variety of environments. To fulfill this requirement, a database of sightlines toward 426 young, reddened stars was constructed using extinction curves based on IUE spectra. The curves were fit and the Fitzpatrick-Massa (FM) parameters were found. FM parameters allow for a quantitative …
The Influence Of Selected Factors On Burnout Among Faculty In Higher Education, Ronald R. Rush
The Influence Of Selected Factors On Burnout Among Faculty In Higher Education, Ronald R. Rush
LSU Doctoral Dissertations
The purpose of this study was to explore demographic variables and job satisfaction and the relationship with burnout among higher education faculty. The sample included 248 tenured professors selected through simple random sampling techniques. A three-part instrument was used: the Maslach Burnout Inventory (MBI-ES), which measured levels of burnout based on subscales of Emotional Exhaustion, Depersonalization, and Personal Accomplishment; the Job Descriptive Index (JDI) and Job in General (JIG) scales, which indicated job satisfaction in areas of: Work on Present Job, Present Pay, Opportunities for Promotion, Supervision on Present Job, People in Present Job, and Job in General; and, a …
Block-Level Discrete Cosine Transform Coefficients For Autonomic Face Recognition, Willie L. Scott, Ii
Block-Level Discrete Cosine Transform Coefficients For Autonomic Face Recognition, Willie L. Scott, Ii
LSU Doctoral Dissertations
This dissertation presents a novel method of autonomic face recognition based on the recently proposed biologically plausible network of networks (NoN) model of information processing. The NoN model is based on locally parallel and globally coordinated transformations. In the NoN architecture, the neurons or computational units form distributed networks, which themselves link to form larger networks. In the general case, an n-level hierarchy of nested distributed networks is constructed. This models the structures in the cerebral cortex described by Mountcastle and the architecture based on that proposed for information processing by Sutton. In the implementation proposed in the dissertation, the …
Electrodeposition Of Nickel-Copper Alloys And Nickel-Copper-Alumina Nanocomposites Into Deep Recesses For Mems, Amrit Panda
Electrodeposition Of Nickel-Copper Alloys And Nickel-Copper-Alumina Nanocomposites Into Deep Recesses For Mems, Amrit Panda
LSU Doctoral Dissertations
Electrodeposition is an important component in the fabrication of micro electro mechanical systems (MEMS). Nickel is the most commonly used material to produce three dimensional microstructures and few material alternatives have been demonstrated. In this dissertation, electrodeposited Ni-Cu alloys and nanocomposites are investigated as possible replacements for nickel in microsystems. Ni-Cu alloys are attractive for their corrosion resistance, magnetic and thermophysical properties. Alumina nanoparticulates included into metal matrices improve hardness and tribology of deposits. The Ni-Cu alloys and Ni-Cu-g-Al2O3 nanocomposites were electrodeposited from a citrate electrolyte, both at low and high pH. Electrodeposition experiments were performed in recessed microelectrodes 500 …
Design And Implementation Of An Ocean Observing System: Wavcis (Wave-Current-Surge Information System) And Its Application To The Louisiana Coast, Xiongping Zhang
Design And Implementation Of An Ocean Observing System: Wavcis (Wave-Current-Surge Information System) And Its Application To The Louisiana Coast, Xiongping Zhang
LSU Doctoral Dissertations
WAVCIS (Wave-Current-Surge Information System for Coastal Louisiana) was designed to measure meteorological and hydrodynamic phenomena along the Louisiana coast. The information measured includes waves, currents, water depth, surge, turbidity, salinity and meteorological conditions. WAVCIS collects data and transfers it back to the data processing laboratory at LSU through wireless communication. The data undergo post-processing and archiving. Users can access the real-time or archived information through the World Wide Web. This dissertation utilized the information provided by WAVCIS stations and NDBC buoys during Hurricane Lili and Tropical Storm to examine temporal and spatial variations of storm induced meteorological and oceanographic dynamics. …
Psychosocial Predictors Of Visceral Adiposity, Paula C. Rhode
Psychosocial Predictors Of Visceral Adiposity, Paula C. Rhode
LSU Doctoral Dissertations
Psychosocial factors are thought to influence health through primarily direct physiological mechanisms or the alteration of health related behaviors. Three factors hypothesized to negatively impact health include arousal, life stress, and depressive symptomatology. One recent theorist suggests that the interaction between psychological stress and stress hormones on the neuroendocrine system may result in adverse changes to body composition, most notably the increased deposition of visceral adipose tissue (Bjorntorp, 1993). The current study prospectively examined the relationship between self-reported stressful life events, depressive symptoms and trait arousal on the deposition of visceral fat, as measured by computerized tomography (CT). Subjects were …
Manufacturing And Analysis Of A Liga Heat Exchanger For The Surface Of A Tube: A Cooling Simulation Of The Leading Edge Region Of A Turbine Blade, Christophe Marques
Manufacturing And Analysis Of A Liga Heat Exchanger For The Surface Of A Tube: A Cooling Simulation Of The Leading Edge Region Of A Turbine Blade, Christophe Marques
LSU Doctoral Dissertations
Fabricating nickel micro heat exchangers directly on planar or non-planar metal surfaces has been demonstrated using the LIGA micromachining process. These heat exchangers can effectively control the temperature of surfaces in high heat flux applications. Of particular interest is the temperature control of gas turbine engine components. The locations in the gas turbine engine where improved, efficient cooling is required includes gas turbine blades, stator vanes, the turbine disk, and the combustor liner. In this dissertation, the primary application of interest is the use of such heat exchangers to cool airfoils such as turbine blades. In the first part of …
The Ecology Of Two Estuarine-Dependent Tonguefishes, The Blackcheek Tonguefish (Symphurus Plagiusa) And The Offshore Tonguefish (S. Civitatium), In Coastal Louisiana, Theodore Scott Switzer
The Ecology Of Two Estuarine-Dependent Tonguefishes, The Blackcheek Tonguefish (Symphurus Plagiusa) And The Offshore Tonguefish (S. Civitatium), In Coastal Louisiana, Theodore Scott Switzer
LSU Doctoral Dissertations
The pattern and process of wetland loss in coastal Louisiana has the potential to influence the distribution and abundance of fishes and macroinvertebrates that utilize inshore estuarine habitat as nurseries during their early life histories. Current management plans designed to stabilize marsh elevations, such as freshwater diversions, may also influence the distribution and abundance of estuarine-dependent nekton. Given the importance of nursery function of inshore estuaries in coastal Louisiana, it is of interest to explore the response of estuarine-dependent organisms to environmental gradients. To this end I examined the ecology of two sympatric tonguefishes, the blackcheek tonguefish (Symphurus plagiusa) and …
On The Geometry And Topology Of Moduli Spaces Of Multi-Polygonal Linkages, Michael Edward Holcomb
On The Geometry And Topology Of Moduli Spaces Of Multi-Polygonal Linkages, Michael Edward Holcomb
LSU Doctoral Dissertations
The geometric, topological, and symplectic properties of moduli spaces (spaces of configurations modulo rotations and translations) of polygonal linkages have been studied by Kapovich, Millson, and Kamiyama, et. al. One can form a polygonal linkage by taking two free linkages and identifying initial and terminal vertices. This can be generalized so that one takes three free linkages and identifies initial and terminal vertices. Then one obtains a linkage which contains multiple polygons, any two of which have shared edges. The geometric and topological properties of moduli spaces of these multi-polygonal linkages are studied. These spaces turn out to be compact …
The Relationship Between Elementary School Foreign Language Study In Grades Three Through Five And Academic Achievement On The Iowa Tests Of Basic Skills (Itbs) And The Fourth-Grade Louisiana Educational Assessment Program For The 21st Century (Leap 21) Test, Carolyn Joyce Taylor-Ward
LSU Doctoral Dissertations
The passage of the federal educational legislation, No Child Left Behind Act of 2001, established foreign languages as a core curricular content area. Nonetheless, educational policy makers at the state and local levels often opt to allocate greater resources and give instructional priority to content areas in which students, and ultimately the school systems themselves, are held accountable through high-stakes testing. Although foreign languages are designated as a core content area, instructional emphasis continues to be placed on curricular areas that factor into state educational accountability programs. The present study employed a mixed-methodology design. The primary goal was to explore …
Off Road Vehicle Soil Suitability Analysis Within The Kisatchie National Forest, Jacqueline Avellanoza Prudente
Off Road Vehicle Soil Suitability Analysis Within The Kisatchie National Forest, Jacqueline Avellanoza Prudente
LSU Doctoral Dissertations
Soil degradation due to improper use of off road vehicle (ORV) is among the major problems in the Kisatchie National Forest (KNF), especially in Catahoula (CRD), Evangeline Unit, Calcasieu (ERD), and Kisatchie Ranger (KRD) districts. The USDA-Forest Service (USFS) maintains designated trails within the forest, but many ORV users create their own trails. To address this issue, a research project was initiated in 2001 to assess the suitability of KNF soils for ORV traffic using Geographical Information System (GIS) software. The objectives were achieved by utilizing soil properties, rainfall events, soil trafficability ratings, Keetch-Byram Drought Index (KBDI), and infiltration parameters. …
The Perceptions Of Effects Of A Study Skills Course, "Dynamics Of Effective Study," On The Academic Achievement Of African American Students At A Dedicated Academic Magnet High School, Josephine Ann Allen
The Perceptions Of Effects Of A Study Skills Course, "Dynamics Of Effective Study," On The Academic Achievement Of African American Students At A Dedicated Academic Magnet High School, Josephine Ann Allen
LSU Doctoral Dissertations
The purpose of this study was to examine the perceptions of students, teachers, and administrators on the effectiveness of a study skills course, "Dynamics of Effective Study," on the academic achievement of African American students at a dedicated academic magnet high school. Qualitative research methods were utilized in this study. Fifteen African American students who completed the study skills course, fifteen African American students who did not take or complete the study skills course, five former study skills teachers, and three administrators from the dedicated academic magnet high school volunteered to participate in the study. Open-ended interviews were conducted with …
Large Eddy Simulations Of Complex Turbulent Flows, Mayank Tyagi
Large Eddy Simulations Of Complex Turbulent Flows, Mayank Tyagi
LSU Doctoral Dissertations
In this dissertation a solution methodology for complex turbulent flows of industrial interests is developed using a combination of Large Eddy Simulation (LES) and Immersed Boundary Method (IBM) concepts. LES is an intermediate approach to turbulence simulation in which the onus of modeling of “universal” small scales is appropriately transferred to the resolution of “problem-dependent” large scales or eddies. IBM combines the efficiency inherent in using a fixed Cartesian grid to compute the fluid motion, along with the ease of tracking the immersed boundary at a set of moving Lagrangian points. Numerical code developed for this dissertation solves unsteady, filtered …
Constraint Preserving Boundary Conditions For The Linearized Einstein Equations, Gioel Calabrese
Constraint Preserving Boundary Conditions For The Linearized Einstein Equations, Gioel Calabrese
LSU Doctoral Dissertations
The successful construction of long time convergent finite difference schemes approximating highly gravitating systems in general relativity remains an elusive task. The presence of constraints and the introduction of artificial time-like boundaries contribute significantly to the difficulty of this problem. Whereas in the absence of boundaries the Bianchi identities ensure that the constraints vanish during evolution provided that they are satisfied initially, this is no longer true when time-like boundaries are introduced. In this work we consider the linearization around the Minkowski space-time in Cartesian coordinates of the generalized Einstein-Christoffel system and analyze different kinds of boundary conditions that are …
Genome Analysis: Mutation Analysis Using Near Infrared Laser-Induced Fluorescence (Nir-Lif) And Single Molecule Detection In Microfluidic Devices, Musundi Ben Wabuyele
Genome Analysis: Mutation Analysis Using Near Infrared Laser-Induced Fluorescence (Nir-Lif) And Single Molecule Detection In Microfluidic Devices, Musundi Ben Wabuyele
LSU Doctoral Dissertations
A number of genotyping methods have been developed for mutation analysis, each of which has its own unique advantage. DNA amplification via polymerase chain reaction (PCR) provides an unlimited supply of material for subsequent genetic analysis even in case where only a single copy of the DNA molecule is present in the sample. Research presented in this dissertation first examines the efficiency of in vitro amplification of single copy DNA with subsequent sequencing analysis of PCR product. The PCR products (amplicons) were investigated for possible alteration, distortions or mutations due to the amplification process. The sequencing data for single copy …
Group Theoretical Approach To Pairing And Non-Linear Phenomena In Atomic Nuclei, Kristina D. Launey
Group Theoretical Approach To Pairing And Non-Linear Phenomena In Atomic Nuclei, Kristina D. Launey
LSU Doctoral Dissertations
The symplectic sp(4) algebra provides a natural framework for studying proton-neutron (pn) and like-nucleon pairing correlations as well as higher-J pn interactions in nuclei when protons and neutrons occupy the same shell. While these correlations manifest themselves most clearly in the binding energies of 0+ ground states, they also have a large effect on the spectra of excited isobaric analog 0+ states. With a view towards nuclear structure applications, a fermion realization of sp(4) is explored and its q-deformed extension, sp(4)q, is constructed for single and multiple shells. The su(2)(q) substructures that enter are associated with isospin symmetry and with …
Influences Of Selected Demographic Variables On The Career Decision-Making Self-Efficacy Of College Seniors, Mary Edith Whitehead Stacy
Influences Of Selected Demographic Variables On The Career Decision-Making Self-Efficacy Of College Seniors, Mary Edith Whitehead Stacy
LSU Doctoral Dissertations
The study was designed (1) to describe college seniors demographically, (2) to assess college seniors perceived level of career-decision making self-efficacy (CDMSE), (3) to examine the relationship between the participant’s CDMSE scores, as measured by the subscales of the Career Decision Self-Efficacy Scale – Short Form© (CDSE-SF), and selected demographic characteristics, and; (4) to determine if a model existed to explain a significant portion of variance in CDMSE based on the selected demographic characteristics. The sample consisted of 382 college seniors attending a four-year public university completing the application for graduation process in the 2002 fall semester. Along with the …
Finite-Horizon Operations Planning For A Lean Supply Chain System, Ahmad Diponegoro
Finite-Horizon Operations Planning For A Lean Supply Chain System, Ahmad Diponegoro
LSU Doctoral Dissertations
This dissertation studies an operational policy for a lean supply chain system consisting of a manufacturer, multiple suppliers and multiple buyers. The manufacturer procures raw materials from the suppliers and converts them into finished products, which are then shipped in batches to the buyers at certain intervals of times. Three distinct but inseparable problems are addressed: single supplier and single buyer with fixed delivery size (FD), multiple suppliers and multiple buyers with individual delivery schedule (MD), and time dependent delivery quantity with trend demand (TD). The mathematical formulations of these supply systems are categorized as mixed-integer, nonlinear programming problems (MINLAP) …
Improved Bottomhole Pressure Control For Underbalanced Drilling Operations, Carlos Perez-Tellez
Improved Bottomhole Pressure Control For Underbalanced Drilling Operations, Carlos Perez-Tellez
LSU Doctoral Dissertations
Maintaining underbalanced conditions from the beginning to the end of the drilling process is necessary to guarantee the success of jointed-pipe underbalanced drilling (UBD) operations by avoiding formation damage and potential hazardous drilling problems such as lost circulation and differential sticking. However, maintaining these conditions is an unmet challenge that continues motivating not only research but also technological developments. This research proposes an UBD flow control procedure, which represents an economical method for maintaining continuous underbalanced conditions and, therefore, to increase well productivity by preventing formation damage. It is applicable to wells that can flow without artificial lift and within …
Hydrodynamic And Sediment Transport Modeling Of Deltaic Sediment Processes, Hassan Shahid Mashriqui
Hydrodynamic And Sediment Transport Modeling Of Deltaic Sediment Processes, Hassan Shahid Mashriqui
LSU Doctoral Dissertations
This dissertation tests the hypothesis that the early phases of deltaic bar and distributary channel formation and sediment transport on an adverse slope could be simulated with a 2D finite element sediment transport model. The models used were RMA2 and SED2D modules of the TABS-MD model suite. A finite element mesh of the lower Atchafalaya River and the delta was developed, using the Surface Water Modeling System (SMS) software package. Calibration and validation of the model were performed, using data collected during field surveys and from available Atchafalaya River archived flow, suspended sediment, and dredging records. In a test simulation …