Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Computer Sciences (1513)
- Environmental Sciences (1353)
- Physics (1038)
- Chemistry (951)
- Life Sciences (894)
-
- Engineering (866)
- Mathematics (789)
- Social and Behavioral Sciences (704)
- Earth Sciences (686)
- Statistics and Probability (427)
- Oceanography and Atmospheric Sciences and Meteorology (425)
- Education (306)
- Astrophysics and Astronomy (298)
- Applied Mathematics (285)
- Natural Resources and Conservation (282)
- Computer Engineering (275)
- Natural Resources Management and Policy (244)
- Electrical and Computer Engineering (221)
- Business (214)
- Databases and Information Systems (207)
- Arts and Humanities (202)
- Science and Mathematics Education (197)
- Sustainability (191)
- Environmental Health and Protection (180)
- Geology (168)
- Physical Chemistry (160)
- Water Resource Management (156)
- Law (154)
- Medicine and Health Sciences (152)
- Institution
-
- University of Nebraska - Lincoln (765)
- Selected Works (403)
- University of Wollongong (349)
- TÜBİTAK (214)
- Utah State University (208)
-
- Wright State University (201)
- Singapore Management University (198)
- University of Nevada, Las Vegas (194)
- SelectedWorks (185)
- Missouri University of Science and Technology (161)
- Louisiana State University (158)
- Old Dominion University (139)
- Technological University Dublin (124)
- Brigham Young University (115)
- Portland State University (115)
- Clemson University (102)
- Wayne State University (95)
- William & Mary (95)
- University of South Florida (94)
- Chinese Chemical Society | Xiamen University (87)
- University of Kentucky (87)
- Western Kentucky University (86)
- University of Massachusetts Amherst (85)
- Air Force Institute of Technology (81)
- California Polytechnic State University, San Luis Obispo (80)
- Embry-Riddle Aeronautical University (75)
- Virginia Commonwealth University (72)
- Dartmouth College (67)
- Syracuse University (67)
- COBRA (66)
- Keyword
-
- Climate change (43)
- Sustainability (38)
- Mathematics (34)
- Education (31)
- Research and Technical Reports (30)
-
- CMMB (29)
- Chemistry (29)
- Western Australia (29)
- GeoQUEST (28)
- West (28)
- 2009 (26)
- Management (25)
- Nanoparticles (25)
- Human–wildlife conflicts (24)
- Australia (23)
- Water (23)
- Water policy (23)
- Water quality (23)
- Western water law (23)
- College for Professional Studies (22)
- School of Computer & Information Science (22)
- Simulation (22)
- Water law (22)
- GIS (21)
- Security (21)
- Data (20)
- Galaxies: evolution (20)
- Groundwater (20)
- Algorithms (19)
- Colorado (19)
- Publication
-
- Research Collection School Of Computing and Information Systems (194)
- Theses and Dissertations (194)
- Faculty of Informatics - Papers (Archive) (158)
- Faculty of Science - Papers (Archive) (156)
- Faculty Publications (143)
-
- Computer Science & Engineering Syllabi (100)
- United States Department of Agriculture Wildlife Services: Staff Publications (95)
- Electronic Theses and Dissertations (94)
- Journal of Electrochemistry (87)
- Turkish Journal of Chemistry (82)
- Physics Faculty Publications (79)
- Nebraska Tractor Tests (75)
- LSU Doctoral Dissertations (67)
- Physics Faculty Research & Creative Works (66)
- Journal of Modern Applied Statistical Methods (64)
- Open Access Theses & Dissertations (63)
- Sci-Tech News (62)
- Dissertations (59)
- School of Natural Resources: Faculty Publications (54)
- UNLV Theses, Dissertations, Professional Papers, and Capstones (54)
- All Dissertations (52)
- LSU Master's Theses (52)
- Doctoral Dissertations (50)
- Publications (49)
- Dartmouth Scholarship (47)
- Articles (45)
- Chemistry Faculty Publications (45)
- Master's Projects (45)
- Chemistry Faculty Research and Publications (43)
- The Mathematics Enthusiast (43)
- Publication Type
Articles 7141 - 7170 of 7616
Full-Text Articles in Physical Sciences and Mathematics
Adaptive Nonparametric Distribution-Free Procedures In Factorial Data Analysis, Richard Nzagong Ferim
Adaptive Nonparametric Distribution-Free Procedures In Factorial Data Analysis, Richard Nzagong Ferim
Mathematics Dissertations
Many statisticians have questioned the basic assumptions about underlying models which might dominate the analysis of the data in many cases. The assumption of normality without much thought is of concern to a growing group of statisticians. If wrongly assumed, the assumption of normality can lead in serious flaws in the analysis of data. It therefore becomes important to consider distribution-free procedures that don't have to rely on the normality assumption. This is where the adaptive procedures come into play. When data is skewed or light tailed, these adaptive methods produce better results than the regular Wilcoxon and parametric methods. …
A Globally Convergent Numerical Method For Coefficient Inverse Problems, Natee Pantong
A Globally Convergent Numerical Method For Coefficient Inverse Problems, Natee Pantong
Mathematics Dissertations
In our terminology "globally convergent numerical method" means a numerical method, whose convergence to a good approximation for the correct solution is independent of the initial approximation. A new numerical imaging algorithm of reconstruction of optical absorption coefficients from near infrared light data with a continuous-wave has been purposed to solves a coefficient inverse problem for an elliptic equation with the data generated by the source running along a straight line. A regularization process, so-called "exterior forward problem", for preprocessing data with noise on the boundary has also been purpose for the problem related to matching fluid in experiment. A …
Projection Methods Require Black Border Removal, George Nagy, Sharad C. Seth, Mahesh Viswanathan
Projection Methods Require Black Border Removal, George Nagy, Sharad C. Seth, Mahesh Viswanathan
School of Computing: Faculty Publications
A persistent flaw in the evaluation of page segmentation algorithms is examined.
Testing Of Gdcl3 Doping In Water Cherenkov Antineutrino Detectors, William Fitzgerald Coleman
Testing Of Gdcl3 Doping In Water Cherenkov Antineutrino Detectors, William Fitzgerald Coleman
LSU Doctoral Dissertations
Improved neutron and neutrino detection using water Cherenkov detectors loaded with gadolinium has been proposed for potential application in both large and small volume detectors. In this thesis, work performed to determine the effect on transparency resulting from use of GdCl3 in stainless steel constructed water Cherenkov detectors is presented. In addition, results of an experiment performed using a small volume water Cherenkov de- tector are reported. This was the first use of gadolinium loaded water to detect reactor antineutrinos.
Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren
Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren
Department of Agronomy and Horticulture: Faculty Publications
Farmers’ attitudes towards viability of specific conservation practices or actions strongly impact their decisions on adoption and change. This review of ‘attitude’ information reveals a wide range of perceptions about what conservation means and what the impacts of adoption will mean in economic and environmental terms. Farmers operate in a tight financial situation, and in parts of the world they are highly dependent on government subsidies, and cannot afford to risk losing that support. Use of conservation practices is most effective when these are understood in the context of the individual farm, and decisions are rooted in land and resource …
Farming Systems Education: Case Study Of Swedish Test Pilots, Lennart Salomonsson, Anna Nilsson, Sofia Palmer, Adam Roigart, Charles A. Francis
Farming Systems Education: Case Study Of Swedish Test Pilots, Lennart Salomonsson, Anna Nilsson, Sofia Palmer, Adam Roigart, Charles A. Francis
Department of Agronomy and Horticulture: Faculty Publications
We describe and analyze a pedagogical experiment that introduced a broad and holistic perspective on complete farming systems, systemic learning tools, and a participatory learning strategy at an early stage in agronomy education. The paper describes the adventure of three students, who came from a conventional agronomy program at the Swedish University of Agricultural Sciences (SLU), who were frustrated with the lack of integrated approaches to the study of agricultural systems and a strong focus on molecular-level processes in their first year of education. They encountered a narrow focus in most courses and the overall curricula of agricultural education that …
Interpreting Surface-Wave Data For A Site With Shallow Bedrock, Daniel W. Casto, Barbara Luke, Carlos Calderon-Macias, Ronald Kaufmann
Interpreting Surface-Wave Data For A Site With Shallow Bedrock, Daniel W. Casto, Barbara Luke, Carlos Calderon-Macias, Ronald Kaufmann
Civil and Environmental Engineering and Construction Faculty Research
The inversion of dispersive Rayleigh-wave data has been shown to be successful in providing reliable estimated shear-wave velocities within unconsolidated materials in the near surface. However, in a case where the multi-channel analysis of surface waves method was applied to a site consisting of clay residuum overlying basalt bedrock, inversion for the fundamental-mode Rayleigh wave resulted in shear-wave velocities within the rock that are less than half of expected values. Forward modeling reveals that the fundamental-mode dispersion curve is hardly sensitive to bedrock velocity perturbations over a practical range of wavelengths, leading to poorly constrained solutions. Standard surface-wave methods can …
Optimal Tracking Control Of Affine Nonlinear Discrete-Time Systems With Unknown Internal Dynamics, Travis Dierks, Sarangapani Jagannathan
Optimal Tracking Control Of Affine Nonlinear Discrete-Time Systems With Unknown Internal Dynamics, Travis Dierks, Sarangapani Jagannathan
Electrical and Computer Engineering Faculty Research & Creative Works
In this paper, direct dynamic programming techniques are utilized to solve the Hamilton Jacobi-Bellman equation forward-in-time for the optimal tracking control of general affine nonlinear discrete-time systems using online approximators (OLA's). the proposed approach, referred as adaptive dynamic programming (ADP), is utilized to solve the infinite horizon optimal tracking control of affine nonlinear discrete-time systems in the presence of unknown internal dynamics and a known control coefficient matrix. the design is implemented using OLA's to realize the optimal feedback control signal and the associated cost function. the feedforward portion of the control input is derived and approximated using an additional …
The Kalman Filter On Time Scales, Nicholas J. Wintz
The Kalman Filter On Time Scales, Nicholas J. Wintz
Doctoral Dissertations
"In this work, we study concepts in optimal control for dynamic equations on time scales, which unfies the discrete and continuous cases. After a brief introduction of dynamic equations on time scales, we will examine controllability and observability for linear systems. Then we construct and solve the linear quadratic regulator for arbitrary time scales. Here, we seek to find an optimal control that minimizes a given cost function associated with a linear system. We will find such an input under two different settings; when the final state is fixed and when it is free. Later, we extend these results to …
Triple Differential Measurements Of Single And Multiple Ionization Of Argon By Electron And Positron Impact, Jared M. Gavin
Triple Differential Measurements Of Single And Multiple Ionization Of Argon By Electron And Positron Impact, Jared M. Gavin
Doctoral Dissertations
"Singly, doubly, and triply differential measurements of single and multiple ionization of Ar by 1 keV positron and electron impact have been measured for projectile energy losses from 0 to 200 eV, scattering angles of 0° to ±5°, and electron emission angles from 45° to 135°. For single ionization, both projectiles show similar overall energy loss distributions but differ with respect to varying scattering angles. Triply differential yields for the electron emission demonstrate the binary and recoil features but the lobes are distorted because of extraction field effects plus variations in grid transmission and solid angle as a function of …
The Potential Of The Synergistic Use Of Passive And Active Remote Sensing Measurements For The Validation Of A Regional Dust Model, V. Amiridis, Menas Kafatos, M. Perez, S. Kazadzis, E. Gerasopoulos, R. E. Mamouri, A. Papayannis, P. Kokkalis, E. Giannakaki, S. Basart, I. Daglis, C S. Zerefos
The Potential Of The Synergistic Use Of Passive And Active Remote Sensing Measurements For The Validation Of A Regional Dust Model, V. Amiridis, Menas Kafatos, M. Perez, S. Kazadzis, E. Gerasopoulos, R. E. Mamouri, A. Papayannis, P. Kokkalis, E. Giannakaki, S. Basart, I. Daglis, C S. Zerefos
Mathematics, Physics, and Computer Science Faculty Articles and Research
A long-lasting Saharan dust event affected Europe on 18–23 May 2008. Dust was present in the free troposphere over Greece, in height ranges between the surface and approximately 4–5 km above sea level. The event was monitored by ground-based CIMEL sunphotometric and multi-wavelength combined backscatter/Raman lidar measurements over Athens, Greece. The dust event had the maximum of its intensity on 20 May. Three-dimensional dust spatial distribution over Greece on that day is presented through satellite synergy of passive and active remote sensing using MODIS and CALIPSO data, respectively. For the period under study, the ground-based measurements are used to characterize …
On-Road Motor Vehicle Emissions Including Ammonia, Sulfur Dioxide And Nitrogen Dioxide (Presentation), Donald H. Stedman, Gary A. Bishop, Allison Peddle
On-Road Motor Vehicle Emissions Including Ammonia, Sulfur Dioxide And Nitrogen Dioxide (Presentation), Donald H. Stedman, Gary A. Bishop, Allison Peddle
Fuel Efficiency Automobile Test Publications
No abstract provided.
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 1, 2008, Gary A. Bishop, Nicolas E. Holubowitch, Donald H. Stedman
Remote Measurements Of On-Road Emissions From Heavy-Duty Diesel Vehicles In California; Year 1, 2008, Gary A. Bishop, Nicolas E. Holubowitch, Donald H. Stedman
Fuel Efficiency Automobile Test Publications
No abstract provided.
Portable Emission Measurements Of Yellowstone Park Snowcoaches And Snowmobiles, Gary A. Bishop, Ryan Stadtmuller, Donald H. Stedman, John D. Ray
Portable Emission Measurements Of Yellowstone Park Snowcoaches And Snowmobiles, Gary A. Bishop, Ryan Stadtmuller, Donald H. Stedman, John D. Ray
Fuel Efficiency Automobile Test Publications
As part of the National Park Service’s Temporary Winter Use Plans Environmental Assessment, the University of Denver has been collecting in-use tailpipe emissions data from snowcoaches and snowmobiles in Yellowstone National Park. During the winter of 2006, using a portable emissions monitoring system, tailpipe data were collected from 10 snowcoaches and 2 four-stroke snowmobiles. These vehicles were operated over a standard route within the park, and the snowcoaches all carried identical passenger loads. These snowcoaches were newer in age with more advanced fuel management technology than those studied earlier, and average emissions were lower as a result (120, 1.7, and …
Studies In Statistical Inference, Sampling Techniques And Demography, Florentin Smarandache, Rajesh Singh, Jayant Singh
Studies In Statistical Inference, Sampling Techniques And Demography, Florentin Smarandache, Rajesh Singh, Jayant Singh
Branch Mathematics and Statistics Faculty and Staff Publications
This volume is a collection of five papers. Two chapters deal with problems in statistical inference, two with inferences in finite population, and one deals with demographic problem. The ideas included here will be useful for researchers doing works in these fields. The following problems have been discussed in the book: Chapter 1. In this chapter optimum statistical test procedure is discussed. The test procedures are optimum in the sense that they minimize the sum of the two error probabilities as compared to any other test. Several examples are included to illustrate the theory. Chapter 2. In testing of hypothesis …
Groups As Graphs, Florentin Smarandache, W.B. Vasantha Kandasamy
Groups As Graphs, Florentin Smarandache, W.B. Vasantha Kandasamy
Branch Mathematics and Statistics Faculty and Staff Publications
Through this book, for the first time we represent every finite group in the form of a graph. The authors choose to call these graphs as identity graph, since the main role in obtaining the graph is played by the identity element of the group. This study is innovative because through this description one can immediately look at the graph and say the number of elements in the group G which are self-inversed. Also study of different properties like the subgroups of a group, normal subgroups of a group, p-sylow subgroups of a group and conjugate elements of a group …
Strong Field Effects On Pulsar Arrival Times: General Orientations, Yan Wang, Teviet Creighton, Richard H. Price, Fredrick A. Jenet
Strong Field Effects On Pulsar Arrival Times: General Orientations, Yan Wang, Teviet Creighton, Richard H. Price, Fredrick A. Jenet
Physics and Astronomy Faculty Publications and Presentations
A pulsar beam passing close to a black hole can provide a probe of very strong gravitational fields even if the pulsar itself is not in a strong field region. In the case that the spin of the hole can be ignored, we have previously shown that all strong field effects on the beam can be understood in terms of two \"universal\" functions: F(φin) and T(φin) of the angle of beam emission φin; these functions are universal in that they depend only on a single parameter, the pulsar/black hole distance from which the beam is emitted. Here we apply this …
Search For Gravitational Waves From Low Mass Binary Coalescences In The First Year Of Ligo’S S5 Data, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, R. Grosso, K. Hayama, H. Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano, Robert Stone, Lappoon R. Tang
Search For Gravitational Waves From Low Mass Binary Coalescences In The First Year Of Ligo’S S5 Data, B. P. Abbott, R. Abbott, Matthew Benacquista, Teviet Creighton, Mario C. Diaz, R. Grosso, K. Hayama, H. Lei, Soumya Mohanty, Soma Mukherjee, Malik Rakhmanov, Joseph D. Romano, Robert Stone, Lappoon R. Tang
Physics and Astronomy Faculty Publications and Presentations
We have searched for gravitational waves from coalescing low mass compact binary systems with a total mass between 2M⊙ and 35M⊙ and a minimum component mass of 1M⊙ using data from the first year of the fifth science run of the three LIGO detectors, operating at design sensitivity. Depending on the mass, we are sensitive to coalescences as far as 150 Mpc from the Earth. No gravitational-wave signals were observed above the expected background. Assuming a population of compact binary objects with a Gaussian mass distribution representing binary neutron star systems, black hole–neutron star binary systems, and binary black hole …
Investigation Of A Neutrosophic Group, A. Elrawy, Florentin Smarandache, Ayat A. Temraz
Investigation Of A Neutrosophic Group, A. Elrawy, Florentin Smarandache, Ayat A. Temraz
Branch Mathematics and Statistics Faculty and Staff Publications
We use a neutrosophic set, instead of an intuitionistic fuzzy because the neutrosophic set is more general, and it allows for independent and partial independent components, while in an intuitionistic fuzzy set, all components are totally dependent. In this article, we present and demonstrate the concept of neutrosophic invariant subgroups. We delve into the exploration of this notion to establish and study the neutrosophic quotient group. Further, we give the concept of a neutrosophic normal subgroup as a novel concept.
Infrared Spectroscopy Of H2 Trapped In Metal Organic Frameworks, Jesse Bennett Hopkins
Infrared Spectroscopy Of H2 Trapped In Metal Organic Frameworks, Jesse Bennett Hopkins
Honors Papers
In this thesis we examine the hydrogen storage properties of four different materials. Because of the global climate crisis and the growing realization that petroleum resources are limited, there has been a strong push to find alternative means of energy storage. At the forefront of this push is the hydrogen economy, the idea that hydrogen gas is a bountiful, clean, alternative means of energy storage. One step towards realizing the hydrogen economy is finding a practical means of hydrogen storage.
The conventional methods of hydrogen storage are in high-pressure gas cylinders or as a liquid. Both of these methods are …
Topology And Infinite Graphs, Nicholas Blackburn Lowery
Topology And Infinite Graphs, Nicholas Blackburn Lowery
Honors Papers
The main focus of this paper will be on two very different areas in which topology is relevant to the study of infinite graphs. The first is the mechanics of compactness proofs, which use a particular group of lemmas to extend results about finite subgraphs to apply to an entire infinite graph. We will explore these results by using them to prove a result of de Bruijn and Erdos, that an infinite graph is k-colorable if its finite subgraphs are k-colorable, in several different ways.
The second area is a relatively new area of study pioneered by Diestel which redefines …
The Use Of A Lock-In Amplifier To Stabilize The Frequency Of A Laser Diode, Jose M. Juarez
The Use Of A Lock-In Amplifier To Stabilize The Frequency Of A Laser Diode, Jose M. Juarez
College Honors Program
We have designed, constructed, and tested a lock-in amplifier with readily available electronic components and homebuilt analog circuits. Its performance is comparable to that of a commercial unit, but it costs significantly less and is much more compact. The various components of our lock-in amplifier are discussed and the basic principles behind the function and operation of this versatile device are explained. We have also assembled a laser system and used the output signal of our lock-in amplifier in a negative feedback loop to stabilize the frequency of our laser to an atomic reference frequency.
Derivatization Of Porphyrins For Dna And Metal Ion Binding, Especially By Employing Secondary Sulfonamide Links, Janet Manono
Derivatization Of Porphyrins For Dna And Metal Ion Binding, Especially By Employing Secondary Sulfonamide Links, Janet Manono
LSU Doctoral Dissertations
Porphyrins are of exceptional importance in nature, science and technology: For instance, as ligands for metals in supramolecular synthesis, as photosenstizers in photodynamic therapy (PDT), and as building blocks for electronic devices. In addition to their application in cancer therapy, porphyrin species also exhibit antiviral activity. New meso-tetraarylporphyrins (TArP, Ar = -C6H4-) of the general formula, T(R1R2NSO2Ar)P, with R1 = N-py-n-CH2 (n = 2, 3 or 4) or SO3- and R2 = H or CH3 were synthesized. These groups were linked to the …
Computational Studies Of The Properties Of Copper Oxide Clusters And The Reactions Of Phenol And Chlorinated Phenols With Copper Oxide Clusters, Gyun-Tack Bae
LSU Doctoral Dissertations
We used ab initio simulations and calculations to study the structures and stabilities of copper oxide clusters, CunOn (n=1-8) and CuOn (n=1-6). The lowest energy structures of neutral and charged copper oxide clusters were determined using primarily the B3LYP/LANL2DZ model chemistry. In CunOn clusters with n=1-8, a transition from planar to nonplanar geometries occurs at n=4. In CuOn clusters with n=1-6, all geometries of neutral, positively, and negatively charged clusters are planar or near planar structures. Selected electronic properties, including binding energies, ionization energies, and electronic affinities, were calculated and examined as a function of n. Stabilities were examined by …
Bottom Boundary Layer Physics And Sediment Transport Along A Transgressive Sand Body, Ship Shoal, South-Central Louisiana: Implications For Fluvial Sediments And Winter Storms, Daijiro Kobashi
LSU Doctoral Dissertations
Ship Shoal, a shore-parallel sand body, was recently recognized as having a unique physical and biological environment and also as a potential sand resource for coastal restoration in coastal Louisiana. Little is known regarding such dynamics, in concert with fluvial sediments and winter storms, influenced in unique ecosystems, and likely in future potential sand mining. This dissertation addresses such the morphodynamics and sedimentary processes and their implications for the mining from the shoal using field measurements and numerical modeling studies. During the winter-spring season, fluvial sediment plumes shifted from the prevailing west to southeast during the post-frontal phases, resulted in …
Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri
Peptide Targeting Of Platinum Anti-Cancer Drug And Synthesis Of Water Soluble Monofunctional Pt(Ii) Complexes Useful For Biological Labeling, Margaret W. Ndinguri
LSU Doctoral Dissertations
Platinum has been used as an inorganic medicinal agent with various applications such as anti cancer agents. Several new targeted Pt(II) conjugates were synthesized having the NGR and LHRH targeting motif. The platinum conjugates bearing the NGR motif revealed selective delivery and destruction of cancer cells that had CD13 receptors compared to untargeted carboplatin drug. The development of targeted chemotherapeutic has opened a new approach for efficient delivery of antitumor toxins with minimal exposure to normal cells. Several peptide sequences are known to have the ability to target tumors, for instance NGR motif which home specifically in solid tumors and …
On-Line Laser Desorption/Ionization Mass Spectrometry, Damien A. Narcisse
On-Line Laser Desorption/Ionization Mass Spectrometry, Damien A. Narcisse
LSU Doctoral Dissertations
Interfaces for on-line laser desorption/ionization mass spectrometry are presented in this dissertation. An on line laser desorption interface allows samples to be introduced directly into the mass spectrometer for high-throughput applications. For this research, a linear time of flight mass spectrometer was constructed with an ionization source designed to accept various laser desorption interfaces. A ball inlet interface was used for continuous analyte deposition at atmospheric pressure and vacuum ionization. A solvent-based cleaning system and a separate capillary for MALDI matrix delivery was utilized for continuous on line sampling with the ball inlet interface. Microfluidic devices were brought into contact …
Algorithms Related To Subgroups Of The Modular Group, Constantin Cristian Caranica
Algorithms Related To Subgroups Of The Modular Group, Constantin Cristian Caranica
LSU Doctoral Dissertations
Classifying subgroups of the modular group PSL_2{Z} is a fundamental problem with applications to modular forms, in addition to its group-theoretic interest. While a lot of research has been done on the congruence subgroups of PSL_2{Z}, very little is known about noncongruence subgroups. The purpose of this thesis is to find and characterize small-index noncongruence subgroups of the modular group PSL_2{Z}. We use the concept of Farey symbol to describe the subgroups of PSL_2{Z}. The first part contains results concerning the geometry of subgroups of PSL_2{Z}. The second part describes a graph-theoretical approach to finding all subgroups of a given …
Unavoidable Minors In Graphs And Matroids, Carolyn Barlow Chun
Unavoidable Minors In Graphs And Matroids, Carolyn Barlow Chun
LSU Doctoral Dissertations
It is well known that every sufficiently large connected graph G has either a vertex of high degree or a long path. If we require G to be more highly connected, then we ensure the presence of more highly structured minors. In particular, for all positive integers k, every 2-connected graph G has a series minor isomorphic to a k-edge cycle or K_{2,k}. In 1993, Oxley, Oporowski, and Thomas extended this result to 3- and internally 4-connected graphs identifying all unavoidable series minors of these classes. Loosely speaking, a series minor allows for arbitrary edge deletions but only allows edges …
Global Positioning System In Curved Space-Time And Other Applications Of General Relativity, Argenis Daniel Da Silva
Global Positioning System In Curved Space-Time And Other Applications Of General Relativity, Argenis Daniel Da Silva
LSU Doctoral Dissertations
In this work, we present some applications of the theory of General Relativity. First, we show a numerical scheme to account for relativistic effects in the Global Positioning System. Then, a couple of applications of astrophysical interest are worked out. These are the study of the gravitational collapse of stars and the dynamical evolution of a three-dimensional Einstein-Klein-Gordon field.