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Proposed Problems Of Mathematics (Vol. Ii), Florentin Smarandache 2010 University of New Mexico

Proposed Problems Of Mathematics (Vol. Ii), Florentin Smarandache

Mathematics and Statistics Faculty and Staff Publications

The first book of “Problèmes avec et sans … problèmes!” was published in Morocco in 1983. I collected these problems that I published in various Romanian or foreign magazines (amongst which: “Gazeta Matematică”, magazine which formed me as problem solver, “American Mathematical Monthly”, “Crux Mathematicorum” (Canada), “Elemente der Mathematik” (Switzerland), “Gaceta Matematica” (Spain), “Nieuw voor Archief” (Holland), etc. while others are new proposed problems in this second volume.

These have been created in various periods: when I was working as mathematics professor in Romania (1984-1988), or co-operant professor in Morocco (1982-1984), or emigrant in the USA (1990-1997). I thank to the ...


Survival Of Grasshopper Sparrows (Ammodramus Savannarum) During Two Important Life Stages In Grassland Managed With Fire And Grazing, Torre James Hovick 2010 Iowa State University

Survival Of Grasshopper Sparrows (Ammodramus Savannarum) During Two Important Life Stages In Grassland Managed With Fire And Grazing, Torre James Hovick

Graduate Theses and Dissertations

Patch-burn grazing (PBG) is a management practice intended to benefit grassland-dependent wildlife. This practice relies on a fire-grazing interaction to create a habitat mosaic that is heterogeneous in terms of structure and composition, mimicking historic conditions. To assess effects of this, we studied nesting and postfledging survival of Grasshopper Sparrows (Ammodramus savannarum), in pastures under two treatments: PBG (grazed, 1/3 burned annually) or graze-and-burned (grazed, entire pasture burned every third year).The study was conducted in Ringgold County, Iowa, on public and private lands. We found 332 Grasshopper Sparrow nests in 2008 and 2009. In 2009 we attached 50 ...


Probabilistic Studies Of Different Investment Strategies, Ling Huang 2010 Iowa State University

Probabilistic Studies Of Different Investment Strategies, Ling Huang

Graduate Theses and Dissertations

Lump Sum (LS), Dollar Cost Averaging (DCA), and Value Averaging (VA) are among the most popular investment strategies. However, conflicting conclusions on their relative performances have been given in the literature due to the use of different time periods of data and simulations. We propose an alternative investment strategy called Threshold Control (TC) based on statistical process monitoring. The idea is that the investor only makes portfolio moves when its market value is far above or below the target value set by the investor. TC can be viewed as a generalization of both LS and VA, and provides more flexibility ...


Solving Distance Geometry Problems For Protein Structure Determination, Atilla Sit 2010 Iowa State University

Solving Distance Geometry Problems For Protein Structure Determination, Atilla Sit

Graduate Theses and Dissertations

A well-known problem in protein modeling is the determination of the structure of a protein with a given set of interatomic distances obtained from either physical experiments or theoretical estimates. A more general form of this problem is known as the distance geometry problem in mathematics, which can be solved in polynomial time if a complete set of exact distances is given, but is generally intractable for a general sparse set of distance data. We investigate the solution of the problem within a geometric buildup framework. We propose a new geometric buildup algorithm for solving the problem using special least-squares ...


Hidden Markov Models For Simultaneous Testing Of Multiple Gene Sets And Adaptive And Dynamic Adaptive Procedures For False Discovery Rate Control And Estimation, Kun Liang 2010 Iowa State University

Hidden Markov Models For Simultaneous Testing Of Multiple Gene Sets And Adaptive And Dynamic Adaptive Procedures For False Discovery Rate Control And Estimation, Kun Liang

Graduate Theses and Dissertations

This dissertation explored important issues of adaptive multiple testing problems. In Chapter 2, we showed that a class of dynamic adaptive procedures provides conservative point estimations for the proportion of true null hypotheses and FDR. These procedures are truly adaptive procedures because of their ability to adapt to the data when estimating null proportion. Thus, the dynamic adaptive procedures offer a solution to the problem of choosing the tuning parameters for adaptive procedures. In Chapter 3, we discussed important issues of gene set testing, which are commonly used in biological research, and the related multiple testing problems. We developed new ...


Analysis Of Variable Vhe Gamma-Ray Emission From The Hard Spectrum Blazar 1es 1218+304, Asif Imran 2010 Iowa State University

Analysis Of Variable Vhe Gamma-Ray Emission From The Hard Spectrum Blazar 1es 1218+304, Asif Imran

Graduate Theses and Dissertations

This thesis is a study of the very high energy gamma-ray emission from the hard spectrum blazar 1ES 1218+304. The data were collected during the 2008/09 observing season by the VERITAS observatory, an array of four atmospheric Cherenkov telescopes in Southern Arizona. This work describes the development of a set of analysis tools suitable for the extraction of the energy spectra of astrophysical objects. Initially, the tools are applied to the Crab nebula data to optimize and calibrate the analysis. Afterwards, the analysis is applied to the high energy observations of the blazar 1ES 1218+304. We report ...


Determination Of Saccharides And Ethanol From Biomass Conversion Using Raman Spectroscopy: Effects Of Pretreatment And Enzyme Composition, Chien-ju Shih 2010 Iowa State University

Determination Of Saccharides And Ethanol From Biomass Conversion Using Raman Spectroscopy: Effects Of Pretreatment And Enzyme Composition, Chien-Ju Shih

Graduate Theses and Dissertations

This thesis focuses on developing quantitative spectroscopic methods to determine products from hydrolysis and fermentation reaction. A dispersive Raman spectrometer with 785 nm incident light is used to measure saccharides and ethanol in complex matrices. An appropriate pretreatment step is critical prior to hydrolysis reaction for reducing spectra interference. Different pretreatment methods are compared systematically and the glucose detection limits in hydrolysates are calculated.

Multipeak fitting model is also constructed in order to analyze two main sugars produced from cellulose and hemicellulose. Different ratios of sugar mixtures are used to examine the model's accuracy. Ammonia-pretreated corn stover is hydrolyzed ...


Understanding The J/Psi Production Mechanism At Phenix, Todd Kempel 2010 Iowa State University

Understanding The J/Psi Production Mechanism At Phenix, Todd Kempel

Graduate Theses and Dissertations

The large mass of the charm quark, along with the abundance of J/ψ mesons observed from proton-proton collisions at PHENIX, allow for new measurements which are sensitive to basic properties of QCD. Two measurements are presented in this document: a transverse single-spin asymmetry (SSA) of J/ψ production and the angular distribution for decay leptons in various reference frames. The decay distribution is directly sensitive to the J/ψ production mechanism, while the transverse SSA is also sensitive to the distribution of gluons in a transversely polarized proton. Taken together, the two measurements provide a wealth of information about ...


Survivability Schemes For Optical Backbone And Access Networks, Taiming Feng 2010 Iowa State University

Survivability Schemes For Optical Backbone And Access Networks, Taiming Feng

Graduate Theses and Dissertations

Network survivability, reflecting the ability of a network to maintain an acceptable level of service during and after failures, is an important requirement for WDM optical networks due to the ultra-high capacity. The most common network failure is the link failure which could cause enormous data loss and lots of service disruption to Internet users. Although single-link failures are the most common failure scenarios, double-link failures can occur in some cases and cause more severe problem. Compared to unicast sessions, multicast sessions suffer more seriously from link failures because a link may carry traffic to multiple destinations rather than to ...


Mechanistic Photochemistry: From Reactive Intermediates To Environmental Remediation, Erin M. Rockafellow 2010 Iowa State University

Mechanistic Photochemistry: From Reactive Intermediates To Environmental Remediation, Erin M. Rockafellow

Graduate Theses and Dissertations

This dissertation exemplifies the utility of light in chemical research and technology, specifically focusing on oxene generation and environmental remediation.

The first study compares direct and sensitized photolysis of dibenzothiophene-S-oxide (DBTO) and dibenzoselenophene-Se-oxide (DBSeO). Quantum yield and solvent oxidation data are used to separate the direct irradiation conditions, plus benzophenone-sensitized and anthraquinone-sensitized irradiation of DBSeO, into one mechanistic class. Acridine-sensitized photolysis of DBSeO and triplet sensizitization of DBTO result in deoxygenation, but go by different mechanisms than the direct irradations. The two sensitized cases that appear mechanistically linked to direct DBTO photolysis are ones in which the spectroscopic triplet of ...


Enabling Knowledge Management Of Organizational Memory For Groups Through Shared Topic Maps, Alok Sharma 2010 Iowa State University

Enabling Knowledge Management Of Organizational Memory For Groups Through Shared Topic Maps, Alok Sharma

Graduate Theses and Dissertations

An Organization's success and growth are increasingly becoming dependent upon how efficiently the Business Processes are managed. Knowledge Management and Organizational Memory have become critical components in the management of Business Processes. As, the Business Process Managers, Participants and End Users are dependent upon information and knowledge from myriad sources, thus their ability to proficiently access, use and generate new knowledge from existing knowledge has become quite vital. Organizations today work as an interconnected web of their Business Processes. Thus to ensure success, to garner the enhanced organizational capabilities and to have sustain performance improvements, they should incorporate knowledge-sharing ...


Mineralogical, Petrological, Stable Isotope, And Fluid Inclusion Studies Of The Palea Kavala Reduced Intrusion-Related And The Transitional Fakos Porphyry Cu-Mo To Epithermal Au-Te Ore Systems, Andrew Fornadel 2010 Iowa State University

Mineralogical, Petrological, Stable Isotope, And Fluid Inclusion Studies Of The Palea Kavala Reduced Intrusion-Related And The Transitional Fakos Porphyry Cu-Mo To Epithermal Au-Te Ore Systems, Andrew Fornadel

Graduate Theses and Dissertations

Reduced intrusion-related gold systems are generally characterized by a Au-Bi-Te-W metal assemblage genetically linked to the emplacement of granitoids. The Palea Kavala ore system, Greece, consists of ~150 minor Fe-Mn (PbyZnyAg), Fe-Mn-Au, Fe-As-Au, Fe-Cu-Au, and Bi-Te-Au ore occurrences that occur primarily in quartz-calcite-sulfide veins (hypogene mineralization), or as supergene bodies, in overlapping zones centered on the ~21-22 Ma granodioritic Kavala pluton, which intrudes metamorphic rocks of the Paleozoic Rhodope metamorphic core complex. The pluton consists mostly of granodiorite with lesser amounts of diorite, tonalite and monzodiorite, which was emplaced along the regional E-W trending Kavala-Komotini fault.

The recently discovered, ~4 ...


Design And Synthesis Of Mixed Oxides Nanoparticles For Biofuel Applications, Senniang Chen 2010 Iowa State University

Design And Synthesis Of Mixed Oxides Nanoparticles For Biofuel Applications, Senniang Chen

Graduate Theses and Dissertations

The work in this dissertation presents the synthesis of two mixed metal oxides for biofuel applications and NMR characterization of silica materials. In the chapter 2, high catalytic efficiency of calcium silicate is synthesized for transesterfication of soybean oil to biodisels. Chapter 3 describes the synthesis of a new Rh based catalyst on mesoporous manganese oxides. The new catalyst is found to have higher activity and selectivity towards ethanol. Chapter 4 demonstrates the applications of solid state Si NMR in the silica materials.


Origin Of The 610Th Avenue Moraine Of The Des Moines Lobe, Story County, Iowa, Suzanne Marie Ankerstjerne 2010 Iowa State University

Origin Of The 610Th Avenue Moraine Of The Des Moines Lobe, Story County, Iowa, Suzanne Marie Ankerstjerne

Graduate Theses and Dissertations

The late-glacial (<∼>15 kyr B.P.) advance of the soft-bedded Des Moines Lobe, the marginal portion of an ice stream of the Laurentide Ice Sheet, deposited regularly-spaced, transverse moraines. These so-called washboard moraines have relief of 1-5 m, an average spacing of <∼>105 m, and are distributed over the footprint of the Des Moines Lobe. Determining the processes responsible for the formation of these moraines may help illuminate aspects of Des Moines Lobe dynamics and origins of submarine transverse ridges adjacent to modern ice sheets.

Washboard moraines may have formed as a result of weak basal sediments extruding into transverse ...


Characterization Of Proton Exchange Materials For Fuel Cells By Solid State Nuclear Magnetic Resonance, Xueqian Kong 2010 Iowa State University

Characterization Of Proton Exchange Materials For Fuel Cells By Solid State Nuclear Magnetic Resonance, Xueqian Kong

Graduate Theses and Dissertations

Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated.

The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by ...


Lipid Biomarker Analysis And Stable Carbon Isotope Studies Of Biofilms In The Green Valley Acid Mine Drainage Site, Indiana, U.S.A., Shamik Das Gupta 2010 Iowa State University

Lipid Biomarker Analysis And Stable Carbon Isotope Studies Of Biofilms In The Green Valley Acid Mine Drainage Site, Indiana, U.S.A., Shamik Das Gupta

Graduate Theses and Dissertations

Lipids were extracted in order to explore the microbial communities in eleven biofilms and four layers of two stromatolite samples, from the Green Valley acid mine drainage site in western Indiana. The high concentrations of phytadiene, polyunsaturated fatty acids, phytol, phytanol, and monounsaturated fatty acid 18:1Δ9 in the biofilms indicated the abundance of phototrophs, including microeukaryotes, algae (mainly diatoms), and fungi. Wax esters in the hydrocarbon fraction possibly suggested the presence of localized anaerobic zones within the biofilms, where the microeukaryotes synthesized the esters by an unusual reverse β-oxidation pathway. Other microbial communities in the biofilms mainly included ...


Coloring And Extremal Problems In Combinatorics, Jacob Manske 2010 Iowa State University

Coloring And Extremal Problems In Combinatorics, Jacob Manske

Graduate Theses and Dissertations

Coloring problems concern partitions of structures. The classic problem of partitioning the set of integers into a finite number of pieces so that no one piece has an arithmetic progression of a fixed length was solved in 1927. Van der Waerden's Theorem shows that it is impossible to do so. The theorem states that if the set of positive integers is partitioned into finitely many pieces, then at least one of the pieces contains arbitrarily long arithmetic progressions.

Extremal problems focus on finding the largest (or smallest) structures which exhibit a certain property. For instance, we may wish to ...


The Rainfall Over Tropical South America Generated By Multiple Scale Processes, Carlos Mauricio Carrillo 2010 Iowa State University

The Rainfall Over Tropical South America Generated By Multiple Scale Processes, Carlos Mauricio Carrillo

Graduate Theses and Dissertations

The rainfall regime over Central America and tropical South America is the most important hydro-meteorological event in the tropics after the Asian-Australian monsoon system. Therefore, in this study we analyzed how the tropical rainfall over tropical South America is developed using a multiple time and space scale approach.

It was found that the rainfall regime is affected mainly by the ENSO, showing two opposite phases not only in the precipitation, but also in the dynamics terms. Although, there is an advance understanding of the role of the intraseasonal mode of the global tropical precipitation, documentation of the role of the ...


Structural And Functional Study Of Multidrug Transporters, Feng Long 2010 Iowa State University

Structural And Functional Study Of Multidrug Transporters, Feng Long

Graduate Theses and Dissertations

Active efflux of antimicrobial agents is one of the most important strategies that bacteria use to ensure their survival in a toxic extracellular environment. Our interest is to elucidate the structural and functional relationships of bacterial multidrug efflux transporters that give rise to antibiotic resistance. In this dissertation, I focus on studying two specific groups, the multidrug and toxic compound extrusion (MATE) family and the resistance-nodulation-division (RND) family, of multidrug efflux transporters. The functions of the two MATE efflux pumps, NorM of Neisseria gonorrhoeae and YdhE of Escherichia coli, are characterized using a variety of biochemical assays, including drug susceptibility ...


A Study Of Synchronization Of Nonlinear Oscillators: Application To Epileptic Seizures, Daisuke Takeshita 2010 Missouri University of Science and Technology

A Study Of Synchronization Of Nonlinear Oscillators: Application To Epileptic Seizures, Daisuke Takeshita

Doctoral Dissertations

"This dissertation focuses on several problems in neuroscience from the perspective of nonlinear dynamics and stochastic processes. The first part concerns a method to visualize the idea of the power spectrum of spike trains, which has an educational value to introductory students in biophysics. The next part consists of experimental and computational work on drug-induced epileptic seizures in the rat neocortex. In the experimental part, spatiotemporal patterns of electrical activities in the rat neocortex are measured using voltage-sensitive dye imaging. Epileptic regions show well-synchronized, in-phase activity during epileptic seizures. In the computational part, a network of a Hodgkin-Huxley type neocortical ...


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