Physical Sciences and Mathematics Commons^™

Greedy Methods For Approximate Graph Matching With Applications For Social Network Analysis, Partha Basuchowdhuri

LSU Master's Theses

In this thesis, we study greedy algorithms for approximate sub-graph matching with attributed graphs. Such algorithms find one or multiple copies of a sub-graph pattern from a bigger data graph through approximate matching. One intended application of sub-graph matching method is in Social Network Analysis for detecting potential terrorist groups from known terrorist activity patterns. We propose a new method for approximate sub-graph matching which utilizes degree information to reduce the search space within the incremental greedy search framework. In addition, we have introduced the notion of a “seed” in incremental greedy method that aims to find a good initial …

Convolution Semigroups, Kevin W. Zito

LSU Doctoral Dissertations

In this dissertation we investigate, compute, and approximate convolution powers of functions (often probability densities) with compact support in the positive real numbers. Extending results of Ursula Westphal from 1974 concerning the characteristic function on the interval $[0,1]$, it is shown that positive, decreasing step functions with compact support can be embedded in a convolution semigroup in $L^1(0,infty)$ and that any decreasing, positive function $pin L^1(0,infty)$ can be embedded in a convolution semigroup of distributions. As an application to the study of evolution equations, we consider an evolutionary system that is described by a bounded, strongly continuous semigroup ${T(t)}_{tgeq0}$ in …

Cbod₅ Treatment And Nitrogen Transformations Of The Marshland Upwelling System In Intermediate And Saltwater Marshes, Lorna Anne Putnam

LSU Doctoral Dissertations

The marshland upwelling system (MUS) was designed to treat domestic wastewater from coastal dwellings where conventional methods are inadequate due to high water tables, poor hydraulic soil conditions, anaerobic soils, and saline groundwater. Currently there is no adequate treatment system available and coastal dwellings are contributing to water quality problems. This study focused on determining the treatment effectiveness of the MUS for organic matter and understanding the specific processes involved in nitrogen treatment.

The treatment of organic matter, measured as five-day carbonaceous biological oxygen demand (CBOD₅), was effective in field tests for both saltwater and intermediate marshes. Global …

Remediating Impacts Of Global Climate Change-Induced Submergence On Salt Marsh Ecosystem Functions, Camille Lafosse Stagg

LSU Doctoral Dissertations

Impacts of global climate change, such as sea level rise and severe drought, have altered the hydrology of coastal salt marshes resulting in submergence and subsequent degradation of ecosystem function. A potential method of rehabilitating these systems is the addition of sediment-slurries to increase the elevation of the marsh surface, thus ameliorating the effects of excessive inundation. Although this technique is growing in popularity, the successful restoration of ecological function after sediment addition has received little attention. The purpose of this research was to determine if sediment subsidized salt marshes are functionally equivalent to natural marshes and whether salt marshes …

Regional Characterisation Of Hard-Bottom Nursery Habitat For Juvenile Caribbean Spiny Lobster (Panulirus Argus) Using Rapid Assessment Techniques, Rodney D. Bertelsen, Mark J. Butler Iv, William F. Herrnkind, John H. Hunt

Biological Sciences Faculty Publications

Shallow, hard-bottom habitat constitutes approximately 30% of the coastal waters of south Florida, United States, yet it is a chronically understudied feature of the marine seascape in this region. In this study, we characterised the general biogeographic and structural features of shallow benthic hard-bottom communities in the Florida Keys, and related those to the abundance of juvenile Caribbean spiny lobster (Panulirus argus), the target of one of Florida's most economically valuable fisheries. We used rapid assessment techniques to survey more than 100 hard-bottom sites in the Florida Keys to estimate the percentage bottom coverage of vegetation (seagrass and …

Is Seagrass An Important Nursery Habitat For The Caribbean Spiny Lobster, Panulirus Argus, In Florida?, Donald C. Behringer, Mark J. Butler Iv, William Herrnkind, John H. Hunt, Charles A. Acosta, William C. Sharp

Biological Sciences Faculty Publications

Caribbean spiny lobster (Panulirus argus) settle preferentially in macroalgal-covered hard-bottom habitat, but seagrass is more prevalent in Florida (United States) and the Caribbean, so even low settlement of lobsters within seagrass could contribute substantially to recruitment if post-settlement survival and growth were high. We tested the role of seagrass and hard-bottom habitats for P. argus recruitment in three ways. We first explored possible density-dependent regulation of early benthic juvenile lobster survival within cages deployed in seagrass and hard-bottom habitats. Second, we compared settlement and survival of P. argus in both habitats, by comparing the recovery of microwire-tagged early …

Phytoplankton Blooms: Their Occurence And Composition Within Virginia's Tidal Tributaries, Harold G. Marshall, Todd A. Egerton

Biological Sciences Faculty Publications

Sporadic algal bloom development within a 10 year monitoring program in Virginia tidal tributaries of Chesapeake Bay is reviewed. These blooms were common events, characteristically producing a color signature to the surface water, typically short lived, occurring mainly from spring into autumn throughout different salinity regions of these rivers, and were produced primarily by dinoflagellates. The abundance threshold levels that would identify bloom status from a non-bloom presence were species specific, varied with the taxon's cell size, and ranged from ca. 10 to 10(4) cells mL(-1). Among the most consistent sporadic bloom producers were the dinoflagellates Akashiwo sanguinea, Cochlodinium …

Laser Desorption From A Room Temperature Ionic Liquid, Peter Ronald Harris

Dissertations, Theses, and Masters Projects

We report laser desorption from a Room Temperature Ionic Liquid (RTIL) as a novel source for time of flight mass spectrometry. We use the 2nd harmonic of an Nd:YAG laser to deposit intensities of 1-50 MW/cm2 via backside illumination onto our RTIL desorption sample. A microstructured metal grid situated on top of a glass microscope slide coated with RTIL serves as our desorption sample. The RTIL we use, 1-Butyl, 3-Methylimidazolium Hexafluorophosphate, remains liquid at pressures below 10-8 torr. The use of liquid desorption sample allows for improved surface conditions, homogeneity and sample life as compared to Matrix Assisted Laser Desorption …

Mathematics Grade 8 Leap Scores: A Predictor Of Student Success In Dimensional Analysis?, Martha Lauren Baggett

LSU Master's Theses

This study investigates whether the Mathematics Grade 8 LEAP score can be used to predict student success in a key concept of chemistry, dimensional analysis. Mathematics Grade 8 LEAP scores of 106 ninth grade students enrolled in physical science during the 2008-09 school year were tested for correlations with student performance on a pre-test of dimensional analysis, a post-test of dimensional analysis, and student learning gain. Significant, positive correlations were observed between the Mathematics Grade 8 LEAP scores and the pre-test scores of dimensional analysis scores, the post-test scores of dimensional analysis scores, and the dimensional analysis student learning gain. …

Multiple Positive Solutions For Nonlinear Third-Order Boundary Value Problems In Banach Spaces, Feng Wang, Hai-Hua Lu, Fang Zhang

Turkish Journal of Mathematics

This paper deals with the positive solutions of nonlinear boundary value problems in Banach spaces. By using fixed point index theory, some sufficient conditions for the existence of at least one or two positive solutions to boundary value problems in Banach spaces are obtained. An example illustrating the main results is given.

Stability Of An Euler-Lagrange Type Cubic Functional Equation, Abbas Najati, Fridoun Moradlou

Turkish Journal of Mathematics

In this paper, we will find out the general solution and investigate the generalized Hyers-Ulam-Rassias stability problem for an Euler-Lagrange type cubic functional equation 2mf(x+my)+2f(mx-y)=(m^3+m)[f(x+y)+f(x-y)]+2(m^4-1)f(y) in Banach spaces and in left Banach modules over a unital Banach *-algebra for a fixed integer m with m\neq0,\pm1.

Strong Convergence Theorems By An Extragradient Method For Solving Variational Inequalities And Equilibrium Problems In A Hilbert Space, Poom Kumam

Turkish Journal of Mathematics

In this paper, we introduce an iterative process for finding the common element of the set of fixed points of a nonexpansive mapping, the set of solutions of an equilibrium problem and the set of solutions of the variational inequality for monotone, Lipschitz-continuous mappings. The iterative process is based on the so-called extragradient method. We show that the sequence converges strongly to a common element of the above three sets under some parametric controlling conditions. This main theorem extends a recent result of Yao, Liou and Yao [Y. Yao, Y. C. Liou and J.-C. Yao, ''An Extragradient Method for Fixed …

On Symmetric Monomial Curves In P^3, Mesut Şahi̇n

Turkish Journal of Mathematics

In this paper, we give an elementary proof of the fact that symmetric arithmetically Cohen-Macaulay monomial curves are set-theoretic complete intersections. The proof is constructive and provides the equations of the surfaces cutting out the monomial curve.

Modules With Unique Closure Relative To A Torsion Theory Ii, Semra Doğruöz, Abdullah Harmanci, Patrick F. Smith

Turkish Journal of Mathematics

We study modules M over a general ring R such that every submodule has a unique closure with respect to a hereditary torsion theory \tau on Mod-R using the fact that the module M satisfies a certain transitivity property on \tau-closed submodules.

Modified Szász-Mirakjan-Kantorovich Operators Preserving Linear Functions, Oktay Duman, Mehmet Ali̇ Özarslan, Biancamaria Della Vecchia

Turkish Journal of Mathematics

In this paper, we introduce a modification of the Szász-Mirakjan-Kantorovich operators, which preserve the linear functions. This type of operator modification enables better error estimation on the interval [1/2,+\infty) than the classical Szász-Mirakjan-Kantorovich operators. We also obtain a Voronovskaya-type theorem for these operators.

Equi-Statistical Extension Of The Korovkin Type Approximation Theorem, Sevda Karakuş, Kami̇l Demi̇rci̇

Turkish Journal of Mathematics

In this paper using equi-statistical convergence, which is stronger than the usual uniform convergence and statistical uniform convergence, we obtain a general Korovkin type theorem. Then, we construct examples such that our new approximation result works but its classical and statistical cases do not work.

Local Fourier Bases And Ultramodulation Spaces, Salti Samarah, Fady Hasan

Turkish Journal of Mathematics

It was proved that local Fourier bases are unconditional bases for modulation spaces M_{p.q}^w. We prove that the local Fourier bases are unconditional bases for ultramodulation spaces M_p^{w_{\gamma}}=M_{p.p}^{w_{\gamma}}, where 0

Some Properties Of Gr-Multiplication Ideals, Hani Khashan

Turkish Journal of Mathematics

In this paper, we study some of the properties of gr-multiplication ideals in a graded ring R. We first characterize finitely generated gr-multiplication ideals and then give a characterization of gr-multiplication ideals by using the gr-localization of R. Finally we determine the set of gr-P-primary ideals of R when P is a gr-multiplication gr-prime ideal of R.

Q-Modules, C. Jayaram, Ünsal Teki̇r

Turkish Journal of Mathematics

In this paper we characterize Q-modules and almost Q-modules. Next we estblish some equivalent conditions for an almost Q-module to be a Q-module. Using these results, some characterizations are given for Noetherian Q-modules.

Strong Differential Subordination, Georgia Irina Oros, Gheorghe Oros

Turkish Journal of Mathematics

The concept of differential subordination was introduced in [4] by S. S. Miller and P. T. Mocanu and the concept of strong differential subordination was introduced in [1] by J. A. Antonino and S. Romaguera. This last concept was applied in the special case of Briot-Bouquet strong differential subordination. In this paper we study the strong differential subordinations in the general case, following the general theory of differential subordinations presented in [4].

Oscillation Of Higher-Order Nonlinear Delay Differential Equations With Oscillatory Coefficients, Başak Karpuz, Özkan Öcalan, Mustafa Kemal Yildiz

Turkish Journal of Mathematics

A criterion is established on the bounded solutions of type higher-order nonlinear neutral differential equations of type oscillatory or tending to zero at infinity [a(t) [x(t)+r(t)x(\kappa(t))]^{(n-1]' +p(t)F(x(\tau(t)))+q(t)G(x(\sigma(t)))= \phi(t), where t\geq t_0, n\geq 2, a,p are positive, r,q,\phi are allowed to alternate in sign infinitely many times, F,G are continuous functions, and \kappa,\tau,\sigma are strictly increasing unbounded continuous delay functions.

On The Geometry Of Null Curves In The Minkowski 4-Space, Recep Aslaner, A. İhsan Boran

Turkish Journal of Mathematics

In this paper, we study the basic results on the general study of null curves in the Minkowski 4-space R_1^4. A transversal vector bundle of a null curve in R_1^4 is constructed using a frenet Frame consisting of two real null and two space-like vectors. The null curves are characterized by using the Frenet frame.

Integral And Homothetic Indecomposability With Applications To Irreducibility Of Polynomials, Fati̇h Koyuncu, Ferruh Özbudak

Turkish Journal of Mathematics

Being motivated by some methods for construction of homothetically indecomposable polytopes, we obtain new methods for construction of families of integrally indecomposable polytopes. As a result, we find new infinite families of absolutely irreducible multivariate polynomials over any field F. Moreover, we provide different proofs of some of the main results of Gao [2].

Partial Open Book Decompositions And The Contact Class In Sutured Floer Homology, Tolga Etgü, Burak Özbağci

Turkish Journal of Mathematics

We demonstrate how to combinatorially calculate the EH-class of a compatible contact structure in the sutured Floer homology group of a balanced sutured three manifold which is associated to an abstract partial open book decomposition. As an application we show that every contact three manifold (closed or with convex boundary) can be obtained by gluing tight contact handlebodies whose EH-classes are nontrivial.

Uniqueness For Meromorphic Functions And Differential Polynomials, Chao Meng

Turkish Journal of Mathematics

In this article, we deal with the uniqueness problems on meromorphic functions concerning differential polynomials and prove the following result: Let f and g be two transcendental meromorphic functions, \alpha be a meromorphic function such that T(r,\alpha)=o(T(r,f)+T(r,g)) and \alpha \not\equiv 0,\infty. Let a be a nonzero constant. Suppose that m,n are positive integers such that n>m+10. If \Psi_f' and \Psi_g' share ``(0,2)", then (i) if m\geq 2, then f(z)\equiv g(z); (ii) if m=1, either f(z)\equiv g(z) or f and g satisfy the algebraic equation R(f,g)\equiv 0, where R(\varpi_1,\varpi_2)=(n+1)(\varpi_1^{n+2}-\varpi_2^{n+2})-(n+2)(\varpi_1^{n+1} -\varpi_2^{n+1}). The results in this paper improve the results of Xiong-Lin-Mori …

Oscillation Of Nonlinear Neutral Delay Differential Equations Of Second-Order With Positive And Negative Coefficients, Mustafa Kemal Yildiz, Başak Karpuz, Özkan Öcalan

Turkish Journal of Mathematics

Some oscillation criteria for the following second-order neutral differential equation [x(t)\pm r(t) f( x(t-\gamma))]''+p(t) g(x(t-\alpha)) -q(t) g(x(t-\beta )) = s(t) where t\geq t_0, \gamma,\alpha,\beta \in R^+ with \alpha \geq \beta, r \in C^2([t_0,\infty ), R^+) , p,q\in C([t_0,\infty ),R^+) and f,g\in C(R,R), s\in C([ t_0,\infty),R) have been obtained. Our results are not restricted with boundedness of solutions.

Solutions For 2n^{Th} Order Lidstone Bvp On Time Scales, Erbi̇l Çeti̇n, S. Gülşan Topal

Turkish Journal of Mathematics

In this paper, we prove the existence of solutions for nonlinear Lidstone boundary value problems by using the monotone method on time scale and also we show the existence of at least one positive solution if f is either superlinear or sublinear by the fixed point theorem in a Banach space.

A Perturbation Of M-Order Derivations On Banach Algebras, Yong-Soo Jung, Kyoo-Hong Park

Turkish Journal of Mathematics

Let \A be a unital Banach algebra and let m, 1 \leq m \leq 4, be an integer. If f: \A \to \A is an approximate m-order derivation in the sense of Hyers-Ulam-Rassias, then f: \A \to \A is an exact m-order derivation.

On Completeness Of Elementary Generalized Solutions Of A Class Of Operator-Differential Equations Of A Higher Order, Rovshan Z. Gumbataliev

Turkish Journal of Mathematics

In this paper we give definition of m-fold completeness and prove a theorem on completeness of elementary generalized solution of corresponding boundary value problems at which the equation describes the process of corrosive fracture of metals in aggressive media and the principal part of the equation has multiple characteristics.

Review Of Hard Road West: History And Geology Along The Gold Rush Trail By Keith Heyer Meldahl, Harmon D. Maher Jr.

Geography and Geology Faculty Publications

The dust jacket of Hard Road West promises familiar pleasures to John McPhee lovers, and so I picked the book up with great anticipation. McPhee’s works have greatly heightened the interest of writers and readers in the genre of creative nonfiction, and while for me, Keith Meldahl’s work does not quite reach McPhee’s stratospheric heights, for the right audience it is definitely a very good read.