Physical Sciences and Mathematics Commons^™

A Note On Computing The Generalized Inverse A^(2)_{T,S} Of A Matrix A, Xiezhang Li, Yimin Wei

Mathematical Sciences: Faculty Publications

The generalized inverse A T,S (2) of a matrix A is a {2}-inverse of A with the prescribed range T and null space S. A representation for the generalized inverse A T,S (2) has been recently developed with the condition σ (GA| T)⊂(0,∞), where G is a matrix with R(G)=T andN(G)=S. In this note, we remove the above condition. Three types of iterative methods for A T,S (2) are presented if σ(GA|T) is a subset of the open right half-plane and they are extensions of existing computational procedures of A T,S (2), including special cases such as the weighted Moore-Penrose …

On Inequalities And Partial Orderings For Weighted Reliability Measures, Broderick O. Oluyede

Mathematical Sciences: Faculty Publications

Inequalities, relations and partial ordering for weighted reliability measures are presented. Inequalities for Lévy distance measure for weighted distributions are obtained in terms of the parent distributions. Reliability inequalities and stability results are established for weighted distributions with monotone hazard and mean residual life functions.

Branch, Crown, Tree And Stand Water Flux In An 180-Year-Old Loblolly Pine Plantation After Thinning, Fertilization, And Throughfall Exclusion Treatments, Shufang Yu

LSU Doctoral Dissertations

Branch and tree sap flux density (SFD) was measured to evaluate the effects of thinning, fertilization, and throughfall exclusion treatments on water use by loblolly pine (Pinus taeda L.) trees. Variations in SFD at different radial xylem depths were also examined to improve estimates of tree water use from sap flux density measured in the outer sapwood. This study was conducted in an 18-year-old loblolly pine plantation in central Louisiana in 1999. The results revealed that SFD was higher in the outer xylem than in the inner xylem and large trees had higher SFD than small trees. Thinning increased daily …

Explicit Multiplicative Relations Between Gauss Sums, Brian J. Murray

LSU Doctoral Dissertations

H.Hasse conjectured that all multiplicative relations between Gauss sums essentially follow from the Davenport-Hasse product formula and the norm relation for Gauss sums. While this is known to be false, very few counterexamples, now known as sign ambiguities, have been given. Here, we provide an explicit product formula giving an infinite class of new sign ambiguities and resolve the ambiguous sign in terms of the order of the ideal class of quadratic primes.

Quantum Gravitational Corrections To Black Hole Geometries, Marco Cavaglia, A. Fabbri

Physics Faculty Research & Creative Works

We calculate perturbative quantum gravity corrections to eternal two-dimensional black holes. We estimate the leading corrections to the AdS₂ black hole entropy and determine the quantum modification of N-dimensional Schwarzschild spacetime.

Effect Of Oxygen Vacancies On The Magnetic Structure Of The La₀.₆Sr₀.₄Feo3-Δ Perovskite: A Neutron Diffraction Study, Zili Chu, William B. Yelon, Jinbo Yang, William Joseph James, Harlan U. Anderson, Yixiang Xie, Satish K. Malik

Physics Faculty Research & Creative Works

Magnetic interactions in perovskite compounds of the type La_1-xSr_xMO_3-δ (M=3d transition such as Mn and Fe) are presumed to arise through a super exchange between 3d electrons of the magnetic ions via oxygen orbitals. The magnetic structure of La_0.6Sr_0.4FeO_3-δ has been studied with neutron diffraction. Oxygen vacancies were created by annealing samples under various gases including N₂, air and mixtures of CO/CO₂. All La_0.6Sr_0.4FeO_3-δ compounds maintain the rhombohedral structure (space group R3̄c). The air- or oxygen-annealed samples have almost no oxygen …

Electrical And Magnetotransport Properties Of Canted Antiferromagnet Dy₅Si₂Ge₂, R. Nirmala, V. Sankaranarayanan, K. Sethupathi, Zili Chu, William B. Yelon, V. Prasad, A. V. Morozkin, Satish K. Malik, S. V. Subramanyam

Physics Faculty Research & Creative Works

Summary form only given. Since the giant magnetocaloric effect is encountered in a ferromagnetic Gd5Si2Ge2 alloy near room temperature it is considered as a suitable material for magnetic refrigerator applications. Also a commensurate structural transition occurs at the magnetic transition temperature and there is a good correlation between the crystal structure and magnetic properties. Such observations have triggered numerous experimental studies on similar rare earth alloys and compounds. We have synthesized its Dy- analogue, namely, Dy5Si2Ge2 and have characterized it by means of room temperature X-ray diffraction, ac magnetic susceptibility (15 K - 300 K), electrical resistivity (at zero field …

Large Enhancement Of Spontaneous Emission Rates Of Inas Quantum Dots In Gaas Microdisks, W. Fang, Alexey Yamilov, Yinfa Ma, J. Y. Xu, S. T. Ho, G. S. Solomon, Hui Cao

Physics Faculty Research & Creative Works

Control of spontaneous emission in a microcavity has many important applications, e.g. improvement of the efficiency of light emitting devices. InAs quantum dots (QDs) embedded in microdisks are ideal systems for spontaneous emission control. The whispering gallery (WG) modes of microdisks have low volume and high quality factor. The homogeneous linewidth of InAs quantum dots is smaller than the spectral width of WG modes. Thus, a large enhancement of the spontaneous emission rates should be expected for QDs coupled to WG modes. However, large inhomogeneous broadening of the QD energy levels and random spatial distribution of the QDs in a …

Analytically Continued Hypergeometric Expression Of The Incomplete Beta Function, Jack C. Straton

Physics Faculty Publications and Presentations

The Incomplete Beta Function is rewritten as a Hypergeometric Function that is the analytic continuation of the conventional form, a generalization of the finite series, which simpifies the Stieltjes transform of powers of a monomial divided by powers of a binomial.

Time-Dependent Current-Density-Functional Theory For The Linear Response Of Weakly Disordered Systems, Carsten A. Ullrich, G. Vignale

Physics Faculty Research & Creative Works

Time-dependent density-functional theory (TDFT) provides a way of calculating, in principle exactly, the linear response of interacting many-electron systems, and thus allows one to obtain their excitation energies. For extended systems, there exist excitations of a collective nature, such as bulk and surface plasmons in metals or intersubband plasmons in doped semiconductor quantum wells. This paper develops a quantitatively accurate first-principles description for the frequency and the linewidth of such excitations in inhomogeneous weakly disordered systems. A finite linewidth in general has intrinsic and extrinsic sources. At low temperatures and outside the region where electron-phonon interaction occurs, the only intrinsic …

Intercomparison Of Number Concentration Measurements By Various Aerosol Particle Counters, A. Ankilov, A. Baklanov, M. Colhoun, K. H. Enderle, J. Gras, Yu Julanov, D. Kaller, A. Lindner, A. A. Lushnikov, R. Mavliev, F. Mcgovern, T. C. O'Connor, Josef Podzimek, O. Preining

Physics Faculty Research & Creative Works

Total aerosol particle number concentrations, as measured by means of 16 different measurement systems, have been quantitatively compared during an international workshop at the Institute for Experimental Physics of the University of Vienna, Austria, which was coordinated within the Committee on Nucleation and Atmospheric Aerosols (ICCP-IUGG). The range of measuring instruments includes Pollak counters (PCO) in use already for several decades, presently available commercial particle counters, as well as laboratory prototypes. The operation of the instruments considered was based on different measurement principles: (1) adiabatic expansion condensation particle counter, (2) flow diffusion condensation particle counter, (3) turbulent mixing condensation particle …

Particle Size Dependent Response Of Aerosol Counters, A. Ankilov, A. Baklanov, M. Colhoun, K. H. Enderle, J. Gras, Yu Julanov, D. Kaller, A. Lindner, A. A. Lushnikov, R. Mavliev, F. Mcgovern, T. C. O'Connor, Josef Podzimek, O. Preining

Physics Faculty Research & Creative Works

During an international workshop at the Institute for Experimental Physics of the University of Vienna, Austria, which was coordinated within the Committee on Nucleation and Atmospheric Aerosols (IAMAS-IUGG), 10 instruments for aerosol number concentration measurement were studied, covering a wide range of methods based on various different measuring principles. In order to investigate the detection limits of the instruments considered with respect to particle size, simultaneous number concentration measurements were performed for monodispersed aerosols with particle sizes ranging from 1.5 to 50 nm diameter and various compositions. The instruments considered show quite different response characteristics, apparently related to the different …

The Fringing Halophytic Vegetation Of Lake Austin: A Study Of Mining Impacts And Vegetation Dynamics, Simone Vellekoop

Theses : Honours

Mining operations in arid regions of Western Australia are faced with many environmental management issues. One such issue is the disposal of mine water to the environment. Mine water is commonly discharged to nearby salt lakes under licence by the Department of Environmental Protection. Licence conditions dictate that the discharge water and the receiving environment be monitored to allow impacts on the environment to be detected. Salt lakes are associated with vegetation communities dominated by halophytic members of the Chenopodiaceae, While these plants are tolerant of salinity extremes, the germination stage of many species requires periods of lowered salinity. There …

Comparative Development And Population Growth Of An Exotic Stemborer, Chilo Partellus (Swinhoe), And An Ecologically Similar Congener, C. Orichalcociliellus (Strand) (Lepidoptera: Crambidae), Jacob C. Mbapila, William A. Overholt, Hosea Y. Kayumbo

All Peer-Reviewed Publications

Studies were conducted to determine the effect of temperature and diet on the development of Chilo partellus (Swinhoe) and Chilo orichalcociliellus (Strand) (Lepidoptera: Crambidae). Developmental times of C. partellus and C. orichalcociliellus for the egg, larval and egg-adult life stages were inversely related to temperature. The larval developmental period of C. orichalcociliellus reared on artificial diet was longer than the developmental period on natural diet. Chilo partellus had a higher intrinsic rate of natural increase than C. orichalcociliellus at all diet/temperature combinations except natural diet at 31°C. © 2002 ICIPE.

Performance Modeling And Prediction For The Scalable Solution Of Partial Differential Equations On Unstructured Grids, Dinesh Kumar Kaushik

Computer Science Theses & Dissertations

This dissertation studies the sources of poor performance in scientific computing codes based on partial differential equations (PDEs), which typically perform at a computational rate well below other scientific simulations (e.g., those with dense linear algebra or N-body kernels) on modern architectures with deep memory hierarchies. We identify that the primary factors responsible for this relatively poor performance are: insufficient available memory bandwidth, low ratio of work to data size (good algorithmic efficiency), and nonscaling cost of synchronization and gather/scatter operations (for a fixed problem size scaling). This dissertation also illustrates how to reuse the legacy scientific and engineering software …

Storm Deposition Of Pisoids In The Humboldt Oolite Member Of The Gilmore City Formation (Mississippian), North-Central Iowa, Shawn C. Thomas, John R. Groves

Journal of the Iowa Academy of Science: JIAS

Pisoids (concentrically laminated carbonate grains, > 2 mm in diameter) are abundant in the upper Humboldt Oolite Member of the Gilmore City Formation (Mississippian). Their cortices are isopachous and nuclei include both intraclasts and fragments of preexisting

pisoids. They occur both as floating grams m a fine grainstone matrix and concentrated at the bases of distinct layers that may be crudely graded beds. Sorting characteristics and the presence of broken and abraded pisoids suggest not only their origin as primary free grams, but also storm influence in the deposition of local pisolite layers. Regionally, the upper Humboldt Oolite is characterized by …

Editorial Board & Iowa Academy Of Science Officers And Directors

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Effects Of Cattle Grazing On Woodlands In Central Iowa, Cathy Mabry

Journal of the Iowa Academy of Science: JIAS

Iowa's forests have undergone a dramatic decline in area since settlement by Europeans. Most of the remaining forests have been degraded by an assortment of human impacts, with cattle grazing the most prominent among them. Using a matched pairs study designed to control for environmental differences among plots, I examined the impact of cattle grazing on the forest understory, canopy trees, and tree regeneration. There were distinct groups of understory species associated with ungrazed and grazed plots. Species associated with ungrazed plots were all native and tended to be perennial herbs with fleshy roots. Ungrazed plots also had species preferring …

Ten Day Pre-Calc Syllabus, Douglas J. Shaw

Faculty Work

No abstract provided.

Fast Inner Product Computation On Short Buses, R. Lin, S. Olariu

Computer Science Faculty Publications

We propose a VLSI inner product processor architecture involving broadcasting only over short buses (containing less than 64 switches). The architecture leads to an efficient algorithm for the inner product computation. Specifically, it takes 13 broadcasts, each over less than 64 switches, plus 2 carry-save additions (t_csa) and 2 carry-lookahead additions (t_cla) to compute the inner product of two arrays of N = 2⁹ elements, each consisting of m = 64 bits. Using the same order of VLSI area, our algorithm runs faster than the best known fast inner product algorithm of Smith and Torng …

Using Simulated Annealing In Geostatistics, Wesley Wells

Theses : Honours

Simulation methods are now used extensively for estimation and prediction in mining and petroleum industries and also in environmental management. In this thesis we describe the method of simulated annealing and examine in detail the GSLIB implementation algorithm SASJM. In the context of two case studies involving both sample and exhaustive data sets, we demonstrate this algorithm and then investigate the effect on the outcome of varying the different algorithm parameters. We also consider the effect of varying the weighting given in the simulated annealing objective function to the reproduction of each of the sample histogram and semivariogram. For the …

Technical Assistance Providers' Guide To Extending Your Reach Through Local Economic Development, Iowa Waste Reduction Center

Iowa Waste Reduction Center Book Gallery

The Guide to Extending Your Reach through Local Economic Developers was prepared as a step-by-step work plan for technical assistance providers to extend their targeted promotional efforts through local economic developers. Building on existing relationships that the economic developers have with area businesses, the Guide provides advice, support material, and insight into the process of partnering with a local, trusted entity to build a strong foundation in the community with regard to utilizing the provider’s technical assistance program to fill the environmental niche in the business community.

Material Weights And Conversions, Iowa Waste Reduction Center, Iowa Waste Exchange

Iowa Waste Reduction Center Book Gallery

The reference information below is designed as a guide for the listing of materials on the Iowa Waste Exchange database. All materials need to be listed in pounds. This information is intended for estimation purposes when the material’s weight is unavailable.

Call Parameters And Facial Features In Bats: A Surprising Failure Of Form Following Function, Amanda Goudy-Trainor, Patricia W. Freeman

School of Natural Resources: Faculty Publications

We attempted to correlate echolocation call parameters to a comprehensive array of ear and nose measurements from 12 families of bats. Surprisingly, we failed to find any significant relationships. We did find consistent differences between nasal and oral emitters such as: (a) nasal emitters have higher frequencies with maximum energy for their size than oral emitters, (b) nasal emitting bats tend to have longer, narrower skulls, and (c) nasal emitters have a shorter distance from the nostril to the eye (muzzle length).

Stable Isotopes Of Carbon As An Invaluable Stratigraphic Tool: An Example From The Cambrian Of The Northern Appalachians, Usa, Bosiljka Glumac, Malkah L. Spivak-Birndorf

Geosciences: Faculty Publications

This study illustrates the usefulness of carbon isotopes in stratigraphic interpretations of poorly fossiliferous strata beyond the resolution possible by biostratigraphy. The Upper Cambrian strata of the lower Gorge Formation in northwestern Vermont have been interpreted as highly condensed continental-slope deposits with a hiatus bracketed by the trilobite fauna of the Dunderbergia zone (Steptoean) and the Saukia zone (upper Sunwaptan). This interpretation was based on information from two thin fossiliferous intervals, the occurrence of one of them being unconfirmed in a recent study. Carbon isotopes provide a means for testing this interpretation because marine carbonate rocks deposited during the Steptoean …

The Role Of Size Exclusion Chromatography-Flame Atomic Absorption Spectrometry In The Treatment Chemistry Of Potable Water, Marina C. Koether

Faculty Articles

The percentage composition of Al₁₃, [AlO₄Al₁₂(OH)₂₄(H₂O)₁₂]⁷⁺, in water treatment coagulants is an important criterion in the development and use of polymeric coagulants. Polymeric coagulants are generally used in cold climates or with highly turbid waters. Size exclusion chromatography–flame atomic absorption spectrometry (SEC-FAAS) can separate Al₁₃ and monomeric Al within 6 min. The percentage composition of Al₁₃ and monomeric Al is determined by solving two simultaneous equations. Due to overlapping peaks, a 10% error is associated with this method of quantification. This method can be …

Influence Of Some Agroforestry Practices On The Temporal Structures Of Nematodes In Western Kenya, Serigne T. Kandji, Callistus K.P.O. Ogol, Alain Albrecht

All Peer-Reviewed Publications

The influence of agroforestry practices on the temporal fluctuation of nematodes was studied in western Kenya. The experiment comprised a fallow phase, which had the following treatments: (1) maize/beans intercropping; (2) maize/beans intercropping with rock phosphate; (3) Crotalaria fallow; (4) Crotalaria fallow with rock phosphate; (5) Crotalaria fallow with rock phosphate (+ Calliandra and napier hedges); and a cultivation phase when all plots were planted to maize and beans. There were strong seasonal fluctuations in the abundance of both free-living and plant-parasitic nematodes. The abundance of plant-parasitic nematodes did not vary among cropping systems during the fallow phase, but varied …

The Classification Of Low Dimensional Nilpotent Lie Algebras, Kimberli C. Tripp

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Nilpotent Lie algebras are the fundamental building blocks for generic (not semi-simple) Lie algebras. In particular, the classification of nilpotent algebras is the first step in classifying and identifying solvable Lie Algebras. The problem of classifying nilpotent Lie algebras was first studied by Umlauf [9] in 1891. More recently, classifications have been given up to dimension six using different techniques by Morosov (1958) [7], Skjelbred and Sund (1977) [8], and up to dimension five by Dixmier (1958) [2]. Using Morosov's method of classification by maximal abelian ideals, Winternitz reproduced the Morosov classification obtaining different canonical forms for the algebras. The …

A Recommendation For Determining The Efficacy Of Weight Removal Estimates For The Pacific Cod Longline Cdq Fishery, Anna L. Furniss

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

In January 2000, the Alaska Department of Community and Economic Development contacted the National Marine Fisheries Service (NMFS) regarding concerns over the methods used to determine catch estimates for the Pacific Cod Community Development Quota (CDQ) fishery. Currently, NMFS determines catch estimates for the Pacific Cod CDQ fishery based on the data collected by observers from the North Pacific Groundfish Observer Program (NPGOP).

Observer estimates for catch are based on the random sampling methods for a longline fishing vessel as described in the North Pacific Groundfish Observer Manual. These sampling methods provide an official total catch (OTC) estimate for each …

Salinity In The Classrom, A Resource For Western Australian Schools, Department Of Agriculture, Western Australia, Department Of Education, Western Australia, State Salinity Council, Western Australia

Books & book chapters

A Western Australian educational resource for teachers and students of the early, middle and early adolescent phases of learning.

Work is sponsored by Alcoa, Shell, State Salinity Council, Department of Agriculture, Water Rivers Commission.

Contributing authors from the Department of Agriculture are: Gale Bell, David Bicknell, Bruce Radys, Kirsty Chandler and Anne Jones.
Contributing authors from Department of Education WA; Kevin Brady, Michael Burke.
Contributing authors from State Salinity Council; Don Crawford.