Physical Sciences and Mathematics Commons^™

On F_S-Supplemented Primary Subgroups Of Finite Groups, Lujin Zhu, Long Miao

Turkish Journal of Mathematics

Let G be a finite group and F a formation of finite groups. A subgroup H of G is called F_s-supplemented in G if there exists a subnormal subgroup T of G such that G = HT and (H \cap T)H_G/H_G is contained in the F-hypercenter Z^F_{\infty}(G/H_G) of G/H_G. In this paper, we study the structure of finite groups by using F_s-supplemented subgroups.

On Cosets In Coxeter Groups, Sarah B. Hart, Peter J. Rowley

Turkish Journal of Mathematics

In this paper the notion of Coxeter length for a subset of a Coxeter group, as introduced in [9], is investigated for various subsets of a Coxeter group. Mostly cosets of various subgroups are examined as well as the associated idea of X-posets, which is a vast generalization of the Bruhat order.

On The Order Of Weighted Approximation By Positive Linear Operators, Tüli̇n Coşkun

Turkish Journal of Mathematics

An estimation of approximation of continuous functions by positive linear operators in weighted norm using the weighted modulus of continuity is established. Application of the main result to the known Gadjiyev-Ibragimov operators is given.

Banach Limit And Some New Spaces Of Double Sequences, Mohammad Mursaleen, Syed Abdul Mohiuddine

Turkish Journal of Mathematics

In this paper, we define and study the Banach limit for double sequences and introduce some new spaces related to the concept of almost and strong almost convergence for double sequences. We characterize these spaces through some sublinear functionals and we also establish some inclusion relations.

C^*-Convexity And C^*-Faces In *-Rings, Ali Ebrahimi Meymand, Gholam Hossein Esslamzadeh

Turkish Journal of Mathematics

Existence of rich algebraic, geometric and topological structures on self-adjoint operator algebras raises the general question that, for a particular theorem which of these structures have made the result work. The present paper is an effort toward the answer of this question, by investigating the role of algebraic structure in the subject of C^*-convexity. In this paper, we extend the notions of C^*-convexity, C^*-extreme point and C^*-face to *-rings and we study some of their properties. We introduce the notion of C^*-convex map on C^*-convex subsets of a *-ring. Moreover we identify optimal points of some unital *-homomorphisms on some …

Small Covers Over Products Of A Polygon With A Simplex, Yanying Wang, Yanchang Chen

Turkish Journal of Mathematics

The equivariant homeomorphism class of an (orientable) small cover over a simple convex polytope P^n bijectively corresponds to the equivalence class of its (orientable) coloring under the action of automorphism group of face poset of P^n. By calculating the number of orbits of group actions we determine the number of equivariant homeomorphism classes of small covers over products of a polygon with a simplex. Moreover, we calculate the number of equivariant homeomorphism classes of all orientable small covers over the product.

On Injective And Subdirectly Irreducible S-Acts Over Left Zero Semigroups, Gholamreza Moghaddasi

Turkish Journal of Mathematics

The aim of this paper is to characterize subdirectly irreducible S-acts over left zero semigroups. Also we compute the number of such acts and specify cogenerators acts over left zero semigroups. To do these we first take another look at the description of injective hulls of the separated S-acts over left zero semigroups.

L^P Regularity Of Some Weighted Bergman Projections On The Unit Disc, Yunus Ergi̇n Zeytuncu

Turkish Journal of Mathematics

We show that weighted Bergman projections, corresponding to weights of the form M(z)(1- z ^2)^\alpha, where \alpha > -1 and M(z) is a radially symmetric, strictly positive and at least C^2 function on \overline{D}, are L^p regular.

Superinjective Simplicial Maps Of The Complexes Of Curves On Nonorientable Surfaces, Elmas Irmak

Turkish Journal of Mathematics

We prove that each superinjective simplicial map of the complex of curves of a compact, connected, nonorientable surface is induced by a homeomorphism of the surface, if (g, n) \in {(1, 0), (1, 1), (2, 0), (2, 1), (3, 0)} or g + n \geq 5, where g is the genus of the surface and n is the number of the boundary components.

Simultaneous Proximinality Of Vector Valued Function Spaces, Mona Khandaqji, Fadi Awawdeh, Jamila Jawdat

Turkish Journal of Mathematics

A characterization of best simultaneous approximation of Köthe spaces of vector-valued functions is given. This characterization is a generalization of some analogous theorems for Orlicz Bochner spaces.

Generalization Of Some Properties Of Banach Algebras To Fundamental Locally Multiplicative Topological Algebras, Ali Zohri, Ali Jabbari

Turkish Journal of Mathematics

In this article we generalized some properties of Banach algebras, to a new class of topological algebras namely fundamental and fundamental locally multiplicative topological algebras (abbreviated by FLM). Also the new notion of sub-multiplicatively metrizable topological algebra is given and some well known spectral properties of Banach algebras are generalized to such kind of algebras.

Hypercyclic Tuples Of The Adjoint Of The Weighted Composition Operators, Rahmat Soltani, Bahram Khani Robati, Karim Hedayatian

Turkish Journal of Mathematics

An n-tuple of commuting operators, (T_1,T_2,...,T_n) on a Hilbert space \cal H is said to be hypercyclic, if there exists a vector x \in \cal H such that the set {T_1^{k_1} T_2^{k_2}... T_n^{k_n}x : k_i \geq 0, i=1,2,...n} is dense in \cal H. In this paper, we give sufficient conditions under which the adjoint of an n-tuple of a weighted composition operator on a Hilbert space of analytic functions is hypercyclic.

Generalized Berwald Metrics, Esmaeil Peyghan, Akbar Tayebi

Turkish Journal of Mathematics

In this paper, we consider a class of Finsler metrics called generalized Berwald metrics which contains the class of Berwald metrics as a special case. We prove that every generalized Berwald metrics with non-zero scalar flag curvature or isotropic Berwald curvature is a Randers metric. Then we prove that on generalized Berwald metrics, the notions of generalized Landsberg and Landsberg curvatures are equivalent.

Bruhat-Chevalley Order On The Rook Monoid, Mahi̇r Bi̇len Can, Lex E. Renner

Turkish Journal of Mathematics

The rook monoid R_n is the finite monoid whose elements are the 0-1 matrices with at most one nonzero entry in each row and column. The group of invertible elements of R_n is isomorphic to the symmetric group S_n. The natural extension to R_n of the Bruhat-Chevalley ordering on the symmetric group is defined in [1]. In this paper, we find an efficient, combinatorial description of the Bruhat-Chevalley ordering on R_n. We also give a useful, combinatorial formula for the length function on R_n.

Lower Bounds For The Maximum Genus Of 4-Regular Graphs, Ding Zhou, Rongxia Hao, Weili He

Turkish Journal of Mathematics

This paper investigates the maximum genus and upper embeddability of connected 4-regular graphs. We obtain lower bounds on the maximum genus of connected 4-regular simple graphs and connected 4-regular graphs without loops in terms of the Betti number. The definition of the Betti number is referred to [Gross and Tucker, Topological Graph Theory, New York, 1987]. Furthermore, we give examples that show that these lower bounds are tight.

Multiplication Modules With Krull Dimension, Mahmood Behboodi, Maryam Molakarimi

Turkish Journal of Mathematics

In ring theory, it is shown that a commutative ring R with Krull dimension has classical Krull dimension and satisfies k.dim(R)=cl.k.dim(R). Moreover, R has only a finite number of distinct minimal prime ideals and some finite product of the minimal primes is zero (see Gordon and Robson [9, Theorem 8.12, Corollary 8.14, and Proposition 7.3]). In this paper, we give a generalization of these facts for multiplication modules over commutative rings. Actually, among other results, we prove that if M is a multiplication R-module with Krull dimension, then: (i) M is finitely generated, (ii) R has finitely many minimal prime …

Essential Normality For Certain Weighted Composition Operators On The Hardy Space H^2, Mahsa Fatehi, Bahram Khani Robati

Turkish Journal of Mathematics

We characterize the essentially normal weighted composition operators C_{\psi,\varphi} on the Hardy space H^2, whenever \varphi is a linear-fractional transformation and \psi \in A(D). Also we investigate the essential normality problem for some other weighted composition operators on H^2.

On Similarity Of Powers Of Shift Operators, Masoumeh Faghih Ahmadi, Karim Hedayatian

Turkish Journal of Mathematics

Let M_z and B denote, respectively, the multiplication operator and the backward shift operator on a weighted Hardy space. We present sufficient conditions so that M_{z^n} is similar to \bigoplus_1^nM_z, and B^n is similar to \bigoplus_1^nB. The first part generalizes a result obtained by Yucheng Li.

An Identity Between The M-Spotty Weight Enumerators Of A Linear Code And Its Dual, İrfan Şi̇ap

Turkish Journal of Mathematics

The m-spotty byte error control codes provide a good source for detecting and correcting errors in semiconductor memory systems using high density RAM chips with wide I/O data (e.g. 8, 16, or 32 bits). m-spotty byte error control codes are very suitable for burst correction. Here, we introduce the m-spotty weights and m-spotty weight enumerator of linear codes over the ring F_2+uF_2 and prove a MacWilliams type identity.

Terrestrial Heat Flow And An Assessment Of Enhanced Geothermal System Resources In Minnesota, Robert Carl Lloyd Klenner

Theses and Dissertations

Low heat flow has been previously reported in Minnesota (406 mW m-2) and the Superior Province of the Canadian Shield (42 ± 8 mW m-2). Low heat flow in Minnesota is due to heat flow measurements made in the mafic rocks of the Mid-Continent Rift System (MCRS) and attributed to the lack of correction for post-glacial climate fluctuations. Radioactivity is a critical heat flow component, particularly in Minnesota where all published heat flow sites are located within the MCRS, creating a bias in the data. The rift is a massive mafic intrusive complex that extends from Moho to the surface, …

Robust Execution Strategy For Scheduling Under Uncertainity, Na Fu

Dissertations and Theses Collection (Open Access)

Resource Constrained Project Scheduling Problems with minimum and maximum time lags (RCPSP/max) provides a general model for resource scheduling in many real-world problems (such as manufacturing and construction engineering). Due to its practical importance and generality, providing effective algorithms and scalable solutions for RCPSP/max is a topic of growing research. Traditional methods have addressed deterministic models with all parameters known with certainty. In this thesis, we are concerned with RCPSP/max problems in an uncertain environment where durations of activities are stochastic and resource availabilities are subject to unforeseen breakdowns. We propose methods for generating robust execution strategy to protect against …

A New Phase Speciation Leaching Procedure For The Determination Of Metals In Oxic And Anoxic Sediments, Brandon R. Gipson

OES Theses and Dissertations

Toxic trace elements such as cadmium, lead, chromium, and arsenic released by human activities can accumulate in marine and estuarine sediments, where these metals are often sequestered until local environmental changes (e.g., redox, salinity, and/or pH) allow these elements to be reintroduced into the food web. In order to assess the extent of toxic trace element contamination in sediment, numerous leaching schemes have been developed that separate sediment-bound trace metals into operationally defined geochemical phases. These "phase speciation" leaching schemes are typically designed with the purpose of being used on either oxic or anoxic sediments. However, natural sediments often contain …

Eukaryotic Microbes In The Deep Sea: Abundance, Diversity, And The Effect Of Pressure, Danielle Morgan-Smith

OES Theses and Dissertations

The dark ocean is vast, high in pressure, cold, and scarce in resources, but has been shown to support a diverse and active microbial community wherever it is studied. Such studies, however, are scarce due to the difficulty of sampling at such depths, and are difficult to interpret due to compounding effects of pressure and temperature on physiology. Protists, functionally defined as the microbial portion of the domain Eukarya, are particularly neglected in studies of deep-sea microbiology. Here, I present three studies on microbial eukaryotes in the deep sea: first, a study of the abundance of microbial eukaryotes in the …

Grazing On Synechococcus Spp. By The Red-Tide Dinoflagellate Karenia Brevis: Implications For Bloom Dynamics In The Gulf Of Mexico, Leo A. Procise

OES Theses and Dissertations

Karenia brevis, the toxic dinoflagellate responsible for massive red tides in the Gulf of Mexico (GOM), causes fish kills, shellfish poisoning, and acute respiratory irritation in humans. Bloom initiation and maintenance have been linked to the physical environment as well as various nutrient input mechanisms. To date, efforts to quantify nitrogen (N) sources fueling K. brevis blooms in the GOM have not included mixotrophic grazing although many dinoflagellates, including K. brevis, are known to be capable of mixotrophy. This dissertation reports field and laboratory results demonstrating that natural bloom populations and K. brevisisolates from the West Florida …

Partitioning Method For Emergent Behavior Systems Modeled By Agent-Based Simulations, O. Thomas Holland

Computational Modeling & Simulation Engineering Theses & Dissertations

Used to describe some interesting and usually unanticipated pattern or behavior, the term emergence is often associated with time-evolutionary systems comprised of relatively large numbers of interacting yet simple entities. A significant amount of previous research has recognized the emergence phenomena in many real-world applications such as collaborative robotics, supply chain analysis, social science, economics and ecology. As improvements in computational technologies combined with new modeling paradigms allow the simulation of ever more dynamic and complex systems, the generation of data from simulations of these systems can provide data to explore the phenomena of emergence.

To explore some of the …

Population Estimate Of Chinese Mystery Snail (Bellamya Chinensis) In A Nebraska Reservoir, Noelle M. Chaine, Craig R. Allen, Kent A. Fricke, Danielle M. Haak, Michelle L. Hellman, Robert A. Kill, Kristine T. Nemec, Kevin L. Pope, Nicholas A. Smeenk, Bruce J. Stephen, Daniel R. Uden, Kody M. Unstad, Ashley E. Vanderham

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The Chinese mystery snail (Bellamya chinensis) is an aquatic invasive species in North America. Little is known regarding this species’ impacts on freshwater ecosystems. It is believed that population densities can be high, yet no population estimates have been reported. We utilized a mark-recapture approach to generate a population estimate for Chinese mystery snail in Wild Plum Lake, a 6.47-ha reservoir in southeast Nebraska. We calculated, using bias-adjusted Lincoln-Petersen estimation, that there were approximately 664 adult snails within a 127 m² transect (5.2 snails/m²). If this density was consistent throughout the littoral zone (depth) of …

Tensor Products Of Vector Seminormed Spaces, John William Dever

Electronic Theses and Dissertations

A vector seminormed space is a triple consisting of a vector space, a Dedekind complete Riesz space, and a vector valued seminorm, called a vector seminorm, defined on the vector space and taking values in the Riesz space. The collection of vector seminormed spaces with suitably defined morphisms is shown to be a category containing finite products. A theory of vector seminorms on the tensor products of vector seminormed spaces is developed in analogy with the theory of tensor products of Banach spaces. Accordingly, a reasonable cross vector seminorm, or simply tensor seminorm, is defined such that a vector seminorm …

Analysis Of Discrete Choice Probit Models With Structured Correlation Matrices, Bhaskara Ravi

Mathematics & Statistics Theses & Dissertations

Discrete choice models are very popular in Economics and the conditional logit model is the most widely used model to analyze consumer choice behavior, which was introduced in a seminal paper by McFadden (1974). This model is based on the assumption that the unobserved factors, which determine the consumer choices, are independent and follow a Gumbel distribution, widely known as the Independence of irrelevant Alternatives (IIA) assumption. Alternate models that relax IIA assumption are the Generalized Extreme Value (GEV) models, which allow dependency between unobserved factors. However, GEV models do not incorporate all dependency patterns, other choice behaviors such as …

Holocene Arroyo Cut And Fills Cycles, South-Central Washington, Matthew Ian Durkee

All Master's Theses

Ephemeral streams have cut deeply incised arroyos into alluvial and eolian sediments in many of the watersheds within the Yakima Training Center (YTC) military reservation, south-central Washington. The most recent channel incision episode along Selah Creek is primarily attributed to multiple failures of an irrigation reservoir dam during the winters of 1909 and 1910. The modern arroyo exposed evidence of at least one previous episode of arroyo incision to a depth of ~4 m that occurred just prior to 1530- 1340 cal yr BP. Filling of this paleo-arroyo with fine to coarse grained sand ceased between 650-103 cal yr BP. …

An Ssvep Brain-Computer Interface: A Machine Learning Approach, Fei Teng

Electronic Theses and Dissertations

A Brain-Computer Interface (BCI) provides a bidirectional communication path for a human to control an external device using brain signals. Among neurophysiological features in BCI systems, steady state visually evoked potentials (SSVEP), natural responses to visual stimulation at specific frequencies, has increasingly drawn attentions because of its high temporal resolution and minimal user training, which are two important parameters in evaluating a BCI system. The performance of a BCI can be improved by a properly selected neurophysiological signal, or by the introduction of machine learning techniques. With the help of machine learning methods, a BCI system can adapt to the …