Physical Sciences and Mathematics Commons^™

Phosphorus Transport In The Bronx River: Qualitative And Quantitative Analysis, Jingyu Wang

Dissertations, Theses, and Capstone Projects

Phosphorus (P) is the primary limiting nutrient for algal growth in freshwater systems. Excessive P from external inputs and release from sediments could accelerate primary productivity leading to eutrophication in the water column, and consequently degrading water quality. The objectives of this study were to predict P bioavailability and estimate spatial and temporal variations in P transport in the Bronx River, New York, USA. The Bronx River originates from the Westchester Davis Brook and Kensico Dam, flowing south through Westchester County (WC) and Bronx to the estuary area where it joins the East River. The total length is about 20 …

Holomorphic Motions And Extremal Annuli, Zhe Wang

Dissertations, Theses, and Capstone Projects

Holomorphic motions, soon after they were introduced, became an important subject in complex analysis. It is now an important tool in the study of complex dynamical systems and in the study of Teichmuller theory. This thesis serves on two purposes: an expository of the past developments and a discovery of new theories.

First, I give an expository account of Slodkowski's theorem based on the proof given by Chirka. Then I present a result about infinitesimal holomorphic motions. I prove the |ε log ε| modulus of continuity for any infinitesimal holomorphic motion. This proof is a very well application of Schwarz's …

Subsurface Compaction A Guide For Wa Farmers And Consultants, Stephen Davies, Alison Lacey

Bulletins 4000 -

For plants to grow in agricultural soils, roots and emerging shoots must be able to force their way through the soil. In soils of high strength, this growth is physically restricted. High strength soils may be due to natural soil characteristics and conditions or develop as a result of agricultural practices and may be in layers or throughout the soil profile.

In agriculture, high strength soils commonly occur as a result of compaction. Compaction of agricultural soils can be in the surface (often caused by stock trampling or rain drop splatter) or in the subsurface (usually in a layer at …

Spitzer 24Μm Survey For Dust Disks Around Hot White Dwarfs, You-Hua Chu, Kate Y.L. Su, Jana Bilikova, Robert A. Gruendl, Orsola De Marco, Martin A. Guerrero, Adria Updike, Kevin Volk, Thomas Rauch

Arts & Sciences Faculty Publications

No abstract provided.

The Swift/Fermi Grb 080928 From 1 Ev To 150 Kev, A. Rossi, S. Schulze, S. Klose, D. A. Kann, A. Rau, H. A. Krimm, G. Jóhannesson, A. Panaitescu, F. Yuan, P. Ferrero, T. Krühler, J. Greiner, P. Schady, S. B. Pandey, L. Amati, P. M.J. Afonso, C. W. Akerlof, L. A. Arnold, C. Clemens, R. Filgas, D. H. Hartmann, A. Küpcü Yoldas, S. Mcbreen, T. A. Mckay, A. Nicuesa Guelbenzu, F. E. Olivares, B. Paciesas, E. S. Rykoff, G. Szokoly, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

We present the results of a comprehensive study of the gamma-ray burst 080928 and of its afterglow. GRB 080928 was a long burst detected by Swift/BAT and Fermi/GBM. It is one of the exceptional cases where optical emission had already been detected when the GRB itself was still radiating in the gamma-ray band. For nearly 100 s simultaneous optical, X-ray and gamma-ray data provide a coverage of the spectral energy distribution of the transient source from about 1 eV to 150 keV. In particular, we show that the SED during the main prompt emission phase agrees with synchrotron radiation.We constructed …

The Two-Component Jet Of Grb 080413b, R. Filgas, T. Krühler, J. Greiner, A. Rau, E. Palazzi, S. Klose, P. Schady, A. Rossi, P. M.J. Afonso, L. A. Antonelli, C. Clemens, S. Covino, P. D’Avanzo, A. Küpcü Yoldas, M. Nardini, A. Nicuesa Guelbenzu, F. Olivares, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

Aims. The quick and precise localization of GRBs by the Swift telescope allows the early evolution of the afterglow light curve to be captured by ground-based telescopes. With GROND measurements we can investigate the optical/near-infrared light curve of the afterglow of gamma-ray burst 080413B in the context of late rebrightening. Methods. Multi-wavelength follow-up observations were performed on the afterglow of GRB 080413B. X-ray emission was detected by the X-ray telescope onboard the Swift satellite and obtained from the public archive. Optical and near-infrared photometry was performed with the seven-channel imager GROND mounted at the MPG/ESO 2.2 m telescope and additionally …

Grb 090426: Discovery Of A Jet Break In A Short Burst Afterglow, A. Nicuesa Guelbenzu, S. Klose, A. Rossi, D.A. Kann, T. Krühler, J. Greiner, A. Rau, F. Olivares E., P.M.J. Afonso, R. Filgas, A. Küpcü Yoldas, S. Mcbreen, M. Nardini, P. Schady, S. Schmidl, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

Context. The link between the duration of GRBs and the nature of their progenitors remains disputed. Short bursts (with durations of less than ∼2 s) are less frequently observed, technically more difficult to localize, and exhibit significantly fainter afterglows. Aims. It is of critical importance to establish whether the burst duration can reliably distinguish the different GRB population models of collapsars and compact stellar mergers. The Swift GRB 090426 provides an unique opportunity to address this question. Its duration (T90 = 1.28 s) places GRB 090426 firmly in the short burst population, while the high redshift (z = 2.609), host …

The Seds And Host Galaxies Of The Dustiest Grb Afterglows, T. Krühler, J. Greiner, P. Schady, S. Savaglio, P. M.J. Afonso, C. Clemens, J. Elliott, R. Filgas, D. Gruber, D. A. Kann, S. Klose, A. Küpcü-Yoldas, S. Mcbreen, F. Olivares, D. Pierini, A. Rau, A. Rossi, M. Nardini, A. Nicuesa Guelbenzu, V. Sudilovsky, Adria Updike

Arts & Sciences Faculty Publications

No abstract provided.

Grb071028b, A Burst Behind Large Amounts Of Dust In An Unabsorbed Galaxy, C. Clemens, J. Greiner, T. Krühler, D. Pierini, S. Savaglio, S. Klose, P.M.J. Afonso, R. Filgas, F.E. Olivares, A. Rau, P. Schady, A. Rossi, A. Küpcü Yoldas, Adria Updike, A. Yoldas

Arts & Sciences Faculty Publications

No abstract provided.

The Nature Of “Dark” Gamma-Ray Bursts, J. Greiner, T. Krühler, S. Klose, P. Afonso, C. Clemens, R. Filgas, D. H. Hartmann, A. Küpcü Yoldas, M. Nardini, F. Olivares E., A. Rau, A. Rossi, P. Schady, Adria Updike

Arts & Sciences Faculty Publications

Context. Thirteen years after the discovery of the first afterglows, the nature of dark gamma-ray bursts (GRB) still eludes explanation: while each long-duration GRB typically has an X-ray afterglow, optical/NIR emission is only seen for 40–60% of them. Aims. Here we use the afterglow detection statistics of the systematic follow-up observations performed with GROND since mid-2007 in order to derive the fraction of “dark bursts” according to different methods, and to distinguish between various scenarios for “dark bursts”. Methods. Observations were performed with the 7-channel “Gamma-Ray Optical and Near-infrared Detector” (GROND) at the 2.2 m MPI/ESO telescope. We used the …

Blow-Up Time For A Semilinear Parabolic Equation With Variable Reaction, Theodore Kouassi Boni, Remi Kouadio Kouakou

Turkish Journal of Mathematics

In this paper, we address the solution of a semilinear heat equation with variable reaction subject to Dirichlet boundary conditions and nonnegative initial datum. Under some assumptions, we show that the solution of the above problem blows up in a finite time, and its blow-up time goes to that of the solution of a certain differential equation. Finally, we give some numerical results to illustrate our analysis.

Homology With Respect To A Kernel Transformation, Seyed Naser Hosseini, Mohammad Zaher Kazemi Baneh

Turkish Journal of Mathematics

In this article we first give the relations between commonly used images of a morphism in a category. We then investigate d-homology in a category with certain properties, for a kernel transformation d. In particular, we show that, in an abelian category, d-homology, where d is induced by the subtraction operation, is the standard homology and that in more general categories the d-homology for a trivial d is zero. We also compute through examples the d-homology for certain kernel transformations d in such categories as R-modules, abelian groups and short exact sequences of R-modules. Finally, we characterize kernel transformations in …

Explicit Constructions Of Rip Matrices And Related Problems, Jean Bourgain, S J. Dilworth, Kevin Ford, Sergei Konyagin, Denka Kutzarova

Faculty Publications

We give a new explicit construction of n×N matrices satisfying the Restricted Isometry Property (RIP). Namely, for someε > 0, largeN, and any n satisfyingN1−ε ≤ n ≤ N, we construct RIP matrices of order k ≥ n1/2+ε and constant δ = n−ε. This overcomesthe natural barrier k = O(n1/2) for proofs based on small coherence, which areused in all previous explicit constructions of RIP matrices. Key ingredients in ourproof are new estimates for sumsets in product sets and for exponential sums with theproducts of sets possessing special additive structure. We also give a construction ofsets of n complex numbers whose …

Predictive Model For Bigheaded Carps In Mississippi River, Jitendra K. Shrestha

Mathematics Theses

Bigheaded carps refer to two species of fish called Silver carp and Bigheaded carp which have invaded the Upper Mississippi River System and are causing nuisance to the native fish like catfish, paddlefish and gizzard Shad by encroaching their habitat. The exponential growth of their population due to their overwhelming reproduction capability and adaptation features calls for a careful study of their population dynamics. In this study, we offer a mathematical model with artificial excessive fishing effort to reduce the population of Bigheaded carps. We numerically observe the correlation among growth rate, fishing rate and the future population of the …

Predicting The Geographic Distribution Of Ancient Soils With Special Reference To The Cretaceous, Arghya Goswami

Earth & Environmental Sciences Dissertations

Different kinds of soils form in different climatic regimes. Soils closely match climatic conditions. Therefore, they are one of the best indicators of past climates. This study uses the "climate envelope" technique developed by Moore (2007) to build a "paleo-soil prediction program". Though factors controlling soil formation are complex (Retallack, 1990), the best fit between a given soil type (Zobler 1999) and the annual range of rainfall and temperature (Legates and Wilmott 1990) are thought to be the primary factors. Each modern soil type has a unique climatic "fingerprint" or "climate envelope" defined by the range of rainfall and temperature …

New Perspectives On Identification And Fostering Mathematically Gifted Students: Matching Research And Practice, Viktor Freiman, Ali Rejali

The Mathematics Enthusiast

This special section of vol8,nos1&2 of The Montana Mathematics Enthusiast is a result of tremendous enthusiastic team work of many outstanding mathematics educators worldwide who are concerned with the issues related to mathematical giftedness and devoted to share with the international community their ideas, research results and best practices. The idea of the special issue on mathematical giftedness arose during the Topic Study Group 6 (TSG6) meeting at the 11th International Congress on Mathematics Education (ICME-11) in Monterrey, Mexico, in 2009 led by Viktor Freiman and Ali Rejali in collaboration with Mark Applebaum, Pablo Dartnell, and Arne Mogensen. More than …

Characterization And Prototyping Of The Rotating Modulator Hard X-Ray/Gamma-Ray Telescope, Brent Budden

LSU Doctoral Dissertations

A hard x-ray/gamma-ray telescope with high sensitivity and wide field of view would be capable of performing an all-sky census of black holes over a wide range of obscuration and accretion rates. As an example, NASA's Black Hole Finder Probe mission was designed to provide a 5-sigma flux sensitivity in a 1-year observation of ~0.02 mCrab in the 10 - 150 keV energy range and 0.5 mCrab in the 150 - 600 keV energy range with 3 - 5 minutes of arc angular resolution. These are significantly higher sensitivity and resolution goals than those of current instruments. The design focus …

Proteomic Analysis Of The Blood Of Alligator Mississippiensis, Lancia Nadinia Fallen Darville-Bowleg

LSU Doctoral Dissertations

My research focus was to investigate alligator blood using mass spectrometry-based proteomics methods to understand their innate immune systems. The first goal was to sequence peptides and proteins from the blood serum and leukocytes using tandem mass spectrometry and de novo sequencing. The second goal was to determine the function of these biological molecules and their relationship to the immune system. One- and two-dimensional gel electrophoresis was used to separate proteins from alligator leukocytes, which were enzymatically digested. The peptides were measured using reversed phase nano-high performance liquid chromatography coupled with tandem mass spectrometry (nano-HPLC-MS/MS) followed with de novo sequencing. …

Simulation Of Storage Time Versus Reverse Bias Current For P^+N And Pin Diodes, Mehmet Serhat Keserli̇oğlu, Hasan Hüseyi̇n Erkaya

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, the reverse-recovery behaviors of pin and p^+n diodes were simulated as a function of the reverse current and carrier lifetime. For this purpose, a 1-D simulation program was written to solve the semiconductor equations. MatLab partial differential equation solver was used. The reverse recovery response of pin and p^+n diodes was obtained for various values of a resistor in series and of carrier lifetime. The transient response for voltage and current was determined.

A New Lvi Assisted Psfb Dc-Dc Converter, Ahmet Faruk Bakan

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a new Phase Shifted Full Bridge (PSFB) Pulse Width Modulated (PWM) isolated dc-dc converter is proposed. In the proposed converter, resonant inductor is replaced with Linear Variable Inductor (LVI) that is controlled by output current. The soft switching operation range is increased and the dependency of ZVS operation on the load current is decreased. The required energy for ZVS operation at low current levels is obtained by means of the high value of the LVI. The value of LVI decreases approximately linearly with increasing current. At high current levels parasitic resonance and duty cycle loss are decreased. …

Godel's Incompleteness Theorems, Jessica Dickson

EWU Masters Thesis Collection

"Incompleteness or inconsistency? Kurt Godel shocked the mathematical community in 1931 when he proved any effectively generated, sufficiently complex, and sound axiomatic system could not be both consistent and complete. This thesis will explore two formal languages of logic and their associated mechanically recursive proof methods with the goal of proving Godel's Incompleteness Theorems. This, in combination with an assignment of a natural number to every string of an axiomatic system, will be used to show a consistent system contains a true statement of the form "This sentence is unprovable," and a complete system contains a proof of its own …

Searching The Protein Structure Database For Ligand-Binding Site Similarities Using Cpass V.2, Robert Powers, Jennifer C. Copeland, Jaime L. Stark, Adam Caprez, Ashu Guru, David R. Swanson

Robert Powers Publications

Background: A recent analysis of protein sequences deposited in the NCBI RefSeq database indicates that ~8.5 million protein sequences are encoded in prokaryotic and eukaryotic genomes, where ~30% are explicitly annotated as “hypothetical” or “uncharacterized” protein. Our Comparison of Protein Active-Site Structures (CPASS v.2) database and software compares the sequence and structural characteristics of experimentally determined ligand binding sites to infer a functional relationship in the absence of global sequence or structure similarity. CPASS is an important component of our Functional Annotation Screening Technology by NMR (FAST-NMR) protocol and has been successfully applied to aid the annotation of a number …

Lessons Learned From Comprehensive Deployments Of Multiagent Cscl Applications I-Minds And Classroomwiki, Nobel Khandaker, Leen-Kiat Soh, L.D. Miller, Adam D. Eck, Hong Jiang

School of Computing: Faculty Publications

Recent years have seen a surge in the use of intelligent computer-supported collaborative learning (CSCL) tools for improving student learning in traditional classrooms. However, adopting such a CSCL tool in a classroom still requires the teacher to develop (or decide on which to adopt) the CSCL tool and the CSCL script, design the relevant pedagogical aspects (i.e., the learning objectives, assessment method, etc.) to overcome the associated challenges (e.g., free riding, student assessment, forming student groups that improve student learning, etc). We have used a multiagent-based system to develop a CSCL application and multiagent frameworks to form student groups that …

Electromagnetic Scattering From Layered Strip Geometries: The Method Of Moments Study With The Sinc Basis, Taner Oğuzer, Fadil Kuyucuoğlu, İbrahi̇m Avgin

Turkish Journal of Electrical Engineering and Computer Sciences

Electromagnetic scattering from strips of layers is analyzed using the method of moments (MoM) for both polarizations in spatial domain with the sinc-type orthogonal sets as basis and testing functions. We exploited the sinc function's properties of exponential convergence, the orthogonality, easy convolution and better handling of singular kernels in MoM procedure resulting in fast performance and reasonable accuracy even in ordinary MoM treatment. We transferred the integral of the Hankel function multiplied by sinc functions to Hankel function introducing a slight error with large band width. We proved that this relative error during the generation of the main matrix …

Vibrations Control Of Light Rail Transportation Vehicle Via Pid Type Fuzzy Controller Using Parameters Adaptive Method, Muzaffer Meti̇n, Rahmi̇ Güçlü

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, a conventional PID type fuzzy controller and parameter adaptive fuzzy controller are designed to control vibrations actively of a light rail transport vehicle which modeled as 6 degree-of-freedom system and compared performances of these two controllers. Rail vehicle model consists of a passenger seat and its suspension system, vehicle body, bogie, primary and secondary suspensions and wheels. The similarity between mathematical model and real system is shown by comparing uncontrolled simulation results and vibration measurements. For carrying a comfortable travel, rail vehicle body and passenger seat vibrations are minimized by adding a controller between rail vehicle body …

A Stationary, Variable Dof Flight Control System For An Unmanned Quadrocopter, Vasfi̇ Emre Ömürlü, Ahmet Kirli, Utku Büyükşahi̇n, Şeref Naci̇ Engi̇n, Sedat Kurtoğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Unmanned air vehicles (UAV) and especially quadrocopters have drawn great attention in recent years because of their maneuverability and nonlinear control problem. Most of the related research concentrate on control; yet, design and communication are also some sub-topics. In this paper, a stationary, four rotor air vehicle with limited/controlled degree of freedom is constructed so that various control algorithms and their changing effects with varying vehicle dynamics can be studied on the ground for safety purposes. Ascending/descending, pitch/yaw/roll motions can be limited by setting the vehicle's degree of freedom mechanically, resulting better net observability of the control algorithms on the …

A Luenberger-Sliding Mode Observer With Rotor Time Constant Parameter Estimation In Induction Motor Drives, Mustafa Gürkan Aydeni̇z, İbrahi̇m Şenol

Turkish Journal of Electrical Engineering and Computer Sciences

The performance and efficiency of an induction motor drive system can be enhanced by online estimation of critical parameters such as rotor time constant. A novel Luenberger-sliding mode observer with a parameter adaptation algorithm is proposed in this paper to compensate for the parameter variation effects. The observer is comparably simple and robust relative to the previously developed observers, and yet suitable for online implementation. Simulation studies for the proposed method were conducted in a MATLAB environment. Observer constants and the control parameters were tuned during the simulation studies and used during the experimental study stage. Experimental verification of the …

Investigation Of Luhn's Claim On Information Retrieval, İlker Kocabaş, Beki̇r Taner Di̇nçer, Bahar Karaoğlan

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, we show how Luhn's claim about the degree of importance of a word in a document can be related to information retrieval. His basic idea is transformed into z-scores as the weights of terms for the purpose of modeling term frequency (tf) within documents. The Luhn-based models represented in this paper are considered as the TF component of proposed TF \times IDF weighing schemes. Moreover, the final term weighting functions appropriate for the TF \times IDF weighting scheme are applied to TREC-6, -7, and -8 databases. The experimental results show relevance to Luhn's claim by having high …

Semi-Direct Galois Covers Of The Affine Line, Linda Gruendken, Laura L. Hall-Seelig, Bo-Hae Im, Ekin Ozman, Rachel Pries, Katherine Stevenson

Mathematics Faculty Publications

Let k be an algebraically closed field of characteristic p > 0. Let G be a semi-direct product of the form (Z/`Z) b o Z/pZ where b is a positive integer and ` is a prime distinct from p. In this paper, we study Galois covers ψ : Z → P 1 k ramified only over ∞ with Galois group G. We find the minimal genus of a curve Z which admits a covering map of this form and we give an explicit formula for this genus in terms of ` and p. The minimal genus occurs when b equals the …

The Carbon Footprint Associated With Water Management Policy Options In The Las Vegas Valley, Nevada, Eleeja Shrestha, Sajjad Ahmad, Walter Johnson, Jacimaria R. Batista

Civil and Environmental Engineering and Construction Faculty Research

A system dynamics model was developed to estimate the carbon dioxide (CO₂) emissions associated with conveyance of water from the water source to the distribution laterals of the Las Vegas Valley. In addition, the impact of several water management policies, including water conservation, reuse, and population growth rate change was evaluated. The results show that, at present, nearly 0.53 million metric tons of CO₂ emissions per year are released due to energy use for water conveyance in distribution laterals of the Valley from Lake Mead, located 32.2 km (20 miles) southeast of the Las Vegas at an …