Physical Sciences and Mathematics Commons^™

Measurements Of K-Shell Fluorescence Yields For Ti, V, Cr, Fe, Co, Ni And Cu Elements And Their Halogen Compounds, Eli̇f Baydaş, Eli̇f Orhan Öz, Mehmet Büyükyildiz

Turkish Journal of Physics

K-shell fluorescence yields \omega_K were measured for the elements Ti, V, Cr, Fe, Co, Ni, Cu and F and Cl compounds of these elements. Measurements were carried out at 10 keV excitation energy using secondary excitation method. K x-rays emitted by samples were counted by a Si(Li) detector with 160 eV resolution at 5.9 keV. Measurement of K-shell fluorescence yields \omega_K for these elements are compared with earlier experimental results obtained by other methods.

Tau Sleptons And Tau Sneutrino Decays In Mssm Under The Cosmological Bounds, Levent Selbuz, Z. Zekeri̇ya Aydin

Turkish Journal of Physics

We present a numerical investigation of the fermionic two-body decays of tau sleptons \tilde \tau_{1,2} and \tau sneutrino in the Minimal Supersymmetric Standard Model with complex parameters. In the analysis we particularly take into account the cosmological bounds imposed by WMAP data. We plot the CP-phase dependences for each fermionic two-body channel of \tilde \tau_{1,2} and \tau sneutrino and speculate about the branching ratios and total (two-body) decay widths. We find that the phase dependences of the decay widths of the third family sleptons are quite significant which can provide viable probes of additional CP sources. We also draw attention …

Conversion Efficiency Calculations For Euv Radiation Emitted From Laser-Produced Tin Plasmas, Betül Atalay, Necla Kenar, Ari̇f Demi̇r

Turkish Journal of Physics

Ni-like and Co-like EUV radiation between 11--17 nm emitted from laser produced tin plasmas was modelled by using the hydrodynamic/atomic physics code EHYBRID. The atomic data were obtained using the Cowan code. The effects of driving laser pulse duration and the laser intensity with different wavelengths were investigated. The maximum conversion efficiency was calculated as 13.4% for a 266 nm Nd:YAG laser with 1 \times 10^{13} W/cm^2 pulse intensity and 5 ns pulse duration.

Garbage On The Green - Public Waste Audit/Recycle Education Event - University Of North Florida, 2009, Colleen Herms, April Moore

Garbage on the Green Reports

Garbage on the Green is an event organized to provide education and awareness of recycling practices on campus at UNF while performing a public waste audit. The purpose of the waste audit is to supply faculty and staff with a representative analysis of waste and recycling practices of representative buildings through the efforts of the Environmental Center and Physical Facilities. Students, faculty and staff are involved in the waste audit process to ensure campus community integration during the event.

Towards Solving Similarity Search Problems Using Fuzzy Concept For Multi-Dimensional Data, Yong Shi

Faculty Articles

In this paper, we present continuous research on data analysis based on our previous work on similarity search problems. PanKNN[13] is a novel technique which explores the meaning of K nearest neighbors from a new perspective, redefines the distances between data points and a given query point Q, and efficiently and effectively select data points which are closest to Q. It can be applied in various data mining fields. In this paper, we applied the Fuzzy concept to improve the performance of PanKNN, targeting the better decision making for the calculation of the distance between a data …

Holocene Carbon Burial By Lakes In Sw Greenland, N. J. Anderson, W. D'Andrea, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

The role of the Arctic in future global change processes is predicted to be important because of the large carbon (C) stocks contained in frozen soils and peatlands. Lakes are an important component of arctic landscapes although their role in storing C is not well prescribed. The area around Kangerlussuaq, SW Greenland (66–68°N, 49–54°W) has ex¬tremely high lake density, with ~20 000 lakes that cover about 14% of the land area. C accumulation rates and standing stock (kg C m⁻²), representing late- to mid-Holocene C burial, were calculated from AMS ¹⁴C-dated sediment cores from 11 lakes. Lake …

Paleolimnological Evidence Of The Effects On Lakes Of Energy And Mass Transfer From Climate And Humans, Peter R. Leavitt, Sherilyn C. Fritz, N. J. Anderson, P. A. Baker, T. Blenckner, L. Bunting, J. Catalan, D. J. Conley, W. O. Hobbs, E. Jeppesen, A. Korhola, S. Mcgowan, K. Rühland, J. A. Rusak, G. L. Simpson, N. Solovieva, J. Werne

Department of Earth and Atmospheric Sciences: Faculty Publications

The premise of this article is that climate effects on lakes can be quantified most effectively by the integration of process-oriented limnological studies with paleolimnological research, particularly when both disciplines operate within a common conceptual framework. To this end, the energy (E)–mass (m) flux framework (Em flux) is developed and applied to selected retrospective studies to demonstrate that climate variability regulates lake structure and function over diverse temporal and spatial scales through four main pathways: rapid direct transfer of E to the lake surface by irradiance, heat, and wind; slow indirect effects of E via changes in …

Interannual Variations In The Opening Date Of The Prudhoe Bay Shipping Season: Links To Atmospheric And Surface Conditions, Sheldon D. Drobot, James A. Maslanik, Mark R. Anderson

Department of Earth and Atmospheric Sciences: Faculty Publications

This paper examines interannual variability in the opening date for the Prudhoe Bay shipping season (1953-2005), considers how variations in antecedent sea-ice and atmospheric conditions influence the opening date, and then develops a forecasting technique to predict whether the opening date will be early, normal, or late. Analysis of antecedent sea ice and atmospheric conditions indicates that there are significant differences in the Bering Sea ice cover as early as February in years preceding early versus late opening dates. In particular, prior to early opening years, the sea-ice cover in the southern Bering Sea is reduced in February, and as …

Obliquity-Paced Pliocene West Antarctic Ice Sheet Oscillations, T. Naish, R. D. Powell, R. Levy, G. Wilson, R. Scherer, F. Talarico, L. Krissek, F. Niessen, M. Pompilio, T. J. Wilson, L. Carter, R. Deconto, P. Huybers, R. Mckay, D. Pollard, J. Ross, D. Winter, P. Barrett, G. Browne, R. Cody, E. A. Cowan, J. Crampton, G. Dunbar, N. Dunbar, F. Florindo, C. Gebhardt, I. Graham, M. Hannah, D. Hansaraj, David M. Harwood, D. Helling, S. Henrys, L. Hinnov, G. Kuhn, P. Kyle, A. La¨Ufer, P. Maffioli, D. Magens, K. Mandernack, W. Mcintosh, C. Millan, R. Morin, C. Ohneiser, T. Paulsen, D. Persico, I. Raine, J. Reed, C. Riesselman, L. Sagnotti, D. Schmitt, C. Sjunneskog, P. Strong, M. Taviani, S. Vogel, T. Wilch, T. Williams

Department of Earth and Atmospheric Sciences: Faculty Publications

Thirty years after oxygen isotope records frommicrofossils deposited in ocean sediments confirmed the hypothesis that variations in the Earth’s orbital geometry control the ice ages¹, fundamental questions remain over the response of the Antarctic ice sheets to orbital cycles². Furthermore, an understanding of the behaviour of the marinebased West Antarctic ice sheet (WAIS) during the ‘warmerthan- present’ early-Pliocene epoch ( ~5–3Myr ago) is needed to better constrain the possible range of ice-sheet behaviour in the context of future global warming³. Here we present a marine glacial record from the upper 600mof the AND-1B sediment …

Towards The Standardization Of Sequence Stratigraphy, Octavian Catuneanu, V. Abreu, J. P. Bhattacharya, M. D. Blum, R. W. Dalrymple, P. G. Eriksson, Christopher R. Fielding, W. L. Fisher, W. E. Galloway, M. R. Gibling, K. A. Giles, J. M. Holbrook, R. Jordan, C. G. St.C. Kendall, B. Macurda, O. J. Martinsen, A. D. Miall, J. E. Neal, D. Nummedal, L. Pomar, H. W. Posamentier, B. R. Pratt, J. F. Sarg, K. W. Shanley, R. J. Steel, A. Strasser, M. E. Tucker, C. Winker

Department of Earth and Atmospheric Sciences: Faculty Publications

Sequence stratigraphy emphasizes facies relationships and stratal architecture within a chronological framework. Despite its wide use, sequence stratigraphy has yet to be included in any stratigraphic code or guide. This lack of standardization reflects the existence of competing approaches (or models) and confusing or even conflicting terminology. Standardization of sequence stratigraphy requires the definition of the fundamental model-independent concepts, units, bounding surfaces and workflow that outline the foundation of the method. A standardized scheme needs to be sufficiently broad to encompass all possible choices of approach, rather than being limited to a single approach or model.

A sequence stratigraphic framework …

Phytoplankton Productivity Across Prairie Saline Lakes Of The Great Plains (Usa): A Step Toward Deciphering Patterns Through Lake Classification Models, Courtney R. Sahm, Jasmine E. Saros, Sherilyn C. Fritz, Christopher L. Osburn, David M. Reineke

Department of Earth and Atmospheric Sciences: Faculty Publications

Abstract: We investigated patterns of primary production across prairie saline lakes in the central and northern Great Plains of the United States. Based on comparative lake sampling in 2004, seasonal predictors of algal primary productivity were identified within subsets of similar lakes using a combination of Akaike's information criterion (AIC) and classification and regression trees (CART). These models indicated complex patterns of nutrient limitation by nitrogen (N), phosphorus (P), and iron (Fe) within different lake groups. Nutrient enrichment assays (control, + Fe, + N, + P, + N + P) were performed in spring and summer of 2006 to determine …

Detecting Source Regions Of Wave Activities In The Tropical Atmosphere By Applying Beamforming To Interpolated Data Grids, Q. Steven Hu, Zhaoning Liang

Department of Earth and Atmospheric Sciences: Faculty Publications

Wave activities are primary sources of weather disturbances and cyclones in the tropical atmosphere. One such activity is the intraseasonal variations in wind, convection, and precipitation in the tropical Indian and western tropical Pacific region. These variations affect the intensity, break and reset, and rainfall in the Indian and the East Asian monsoons. Detecting the source regions of these wave activities is essential for understanding and for prediction of wave development. In this study, a fixed beamforming method is proposed to deduce source regions of some wave activities in the tropical atmosphere. This method is tested with simulations of single …

Does Sedimentary 231Pa/230Th From The Bermuda Rise Monitor Past Atlantic Meridional Overturning Circulation?, Jörg Lippold, Jens Grützner, Diane Winter, Yann Lahaye, Augusto Mangini, Marcus Christl

Department of Earth and Atmospheric Sciences: Faculty Publications

Ocean circulation may have undergone reductions and reinvigorations in the past closely tied to regional climate changes. Measurements of ²³¹Pa/²³⁰Th ratios in a sediment core from the Bermuda Rise have been interpreted as evidence that the Atlantic Meridional Overturning Circulation (AMOC) was weakened or completely eliminated during a period of catastrophic iceberg discharges (Heinrich-Event 1, H1). Here we present new data from the Bermuda Rise that show further ²³¹Pa/²³⁰Th peaks during Heinrich-2 (H2) and Heinrich-3 (H3). Additionally, a tight correlation between diatom abundances (biogenic silica) and ²³¹Pa/²³⁰Th is discovered in this …

The Dilemma Of Disappearing Diatoms: Incorporating Diatom Dissolution Data Into Paleoenvironmental Modeling And Reconstruction, David B. Ryves, Richard W. Battarbee, Sherilyn C. Fritz

Department of Earth and Atmospheric Sciences: Faculty Publications

Taphonomic issues pose fundamental challenges for Quaternary scientists to recover environmental signals from biological proxies and make accurate inferences of past environments. The problem of microfossil preservation, specifically diatom dissolution, remains an important, but often overlooked, source of error in both qualitative and quantitative reconstructions of key variables from fossil samples, especially those using relative abundance data. A first step to tackling this complex issue is establishing an objective method of assessing preservation (here, diatom dissolution) that can be applied by different analysts and incorporated into routine counting strategies. Here, we establish a methodology for assessment of diatom dissolution under …

Estimating Hydraulic Conductivity From Drainage Patterns Derived From Dem -- A Case Study In The Oregon Cascades, B. P. Grudzinski, W. Luo, Daryll Pederson

Department of Earth and Atmospheric Sciences: Faculty Publications

Hydraulic conductivity is an important parameter in hydrology which describes the ease with which water moves through porous media. This parameter is also important in understanding the hydrology of Mars. On Earth, this parameter can be measured by conducting controlled experiments in laboratories or conducting pumping tests in the field. This study introduces a new method of estimating hydraulic conductivity from drainage dissection pattern derived from digital elevation model (DEM). This method can be applied to Mars if it is robustly tested on Earth.

Inventories And Mobilization Of Unsaturated Zone Sulfate, Fluoride, And Chloride Related To Land Use Change In Semiarid Regions, Southwestern United States And Australia, Bridget R. Scanlon, David A. Stonestrom, Robert C. Reedy, Fred W. Leaney, John B. Gates, Richard G. Cresswell

Department of Earth and Atmospheric Sciences: Faculty Publications

Unsaturated zone salt reservoirs are potentially mobilized by increased groundwater recharge as semiarid lands are cultivated. This study explores the amounts of pore water sulfate and fluoride relative to chloride in unsaturated zone profiles, evaluates their sources, estimates mobilization due to past land use change, and assesses the impacts on groundwater quality. Inventories of water-extractable chloride, sulfate, and fluoride were determined from borehole samples of soils and sediments collected beneath natural ecosystems (N = 4), nonirrigated ("rain-fed") croplands (N = 18), and irrigated croplands (N = 6) in the southwestern United States and in the Murray Basin, …

Why Did Lagrange "Prove" The Parallel Postulate?, Judith V. Grabiner

Pitzer Faculty Publications and Research

In 1806, Joseph-Louis Lagrange read a memoir "proving" Euclid's parallel postulate to the Institut de France in Paris. The memoir still exists in manuscript, and we’ll look at what it says. We ask why he tried to prove the postulate, and why he attacked the problem in the way that he did. We also look at how the ideas in this manuscript are related to such things as Lagrange’s philosophy of mathematics, artists’ ideas about space, Newtonian mechanics, and Leibniz's Principle of Sufficient Reason. Finally, we reflect on how this episode changes our views about eighteenth-century attitudes toward geometry, space, …

On Fourier Parabolic And Wave Equation, Mekki Terbeche, Broderick O. Oluyede

Department of Mathematical Sciences Faculty Publications

This paper is devoted to a diffusion (heat) and wave equations for the function of two independent variables. We establish a criterion for existence and uniqueness of the solution of Fourier parabolic equation using Taylor series. A formal solution for a wave equation is investigated.

Gorenstein Flat Dimension Of Complexes, Alina Iacob

Department of Mathematical Sciences Faculty Publications

We define a notion of Gorenstein flat dimension for unbounded complexes over left GF-closed rings. Over Gorenstein rings we introduce a notion of Gorenstein cohomology for complexes; we also define a generalized Tate cohomology for complexes over Gorenstein rings, and we show that there is a close connection between the absolute, the Gorenstein and the generalized Tate cohomology.

Introducing Interior-Point Methods For Introductory Operations Research Courses And/Or Linear Programming Courses, Goran Lesaja

Department of Mathematical Sciences Faculty Publications

In recent years the introduction and development of Interior-Point Methods has had a profound impact on optimization theory as well as practice, influencing the field of Operations Research and related areas. Development of these methods has quickly led to the design of new and efficient optimization codes particularly for Linear Programming. Consequently, there has been an increasing need to introduce theory and methods of this new area in optimization into the appropriate undergraduate and first year graduate courses such as introductory Operations Research and/or Linear Programming courses, Industrial Engineering courses and Math Modeling courses. The objective of this paper is …

Establishment Of Weak Conditions For Darboux-Goursat-Beudon Theorem, Mekki Terbeche, Broderick O. Oluyede

Department of Mathematical Sciences Faculty Publications

This paper is devoted to the establishment of weak conditions for Darboux-Goursat-Beudon (DGB) theorem in order to improve analogous results in [1, 7]. By adapting a technique proposed by [7] in another setting [8] via majorant method, we obtain the generalization of DGB theorem.

Empirical Development Of An Instructional Product And Its Impact On Mastery Of Geometry Concepts, Donaldson Williams

Dissertations

Problem

Relatively poor levels of mathematical thinking among American school children have been identified as a major issue over the past half century. Many efforts have been made to increase the mathematics performance of children in schools. Additionally, out-of-school-time programs have attempted to address this issue as well. Holistic development is one of the distinguishing features of Seventh-day Adventist instructional programs. Yet, as of 2007, the Pathfinder program, an informal educational program operated by the world-wide Seventh-day Adventist church, had no instructional product designed to foster participants’ cognitive development in mathematics. This study focused on the empirical development of an …

Systems Chemistry And Parrondo’S Paradox: Computational Models Of Thermal Cycling, Daniel C. Osipovitch, Carl Barratt, Pauline M. Schwartz

Chemistry and Chemical Engineering Faculty Publications

A mathematical concept known as Parrondo’s paradox motivated the development of several novel computational models of chemical systems in which thermal cycling was explored. In these kinetics systems we compared the rates of formation of product under cycling temperature and steady-sate conditions. We found that a greater concentration of product was predicted under oscillating temperature conditions. Our computational models of thermal cycling suggest new applications in chemical and chemical engineering systems.

Raising Heart Rate With Dance Pad Based Computer Games, Martin Masek, Philip Hingston, Matthew Carrigy, Liam Collins, Kazunori Nosaka

Research outputs pre 2011

No abstract provided.

Fuel Characteristics And Dynamics In Shrublands Of The Transitional Rainfall Zone, Western Australia, Sarah Dalgleish

Theses : Honours

Within the Mediterranean shrublands, fires are particularly intensive and widespread. In the Transitional Rainfall Zone in Western Australia, these large fires bum in areas with high conservation value, and present risks to human lives and infrastructure on properties in the region. The concern for the effect fires have on anthropocentric and ecological values in these shrublands makes it a priority in management to reduce the risks. Of the environmental and biotic factors that influence a fire, fuel is one of the most significant as it has the capacity to determine fire prope1iies such as the intensity, extent, bum pattern within …

N- And C-Terminal Domains In Human Holocarboxylase Synthetase Participate In Substrate Recognition, Yousef I. Hassan, Hideaki Moriyama, Lars J. Olsen, Xin Bi, Janos Zempleni

Hideaki Moriyama Publications

Holocarboxylase synthetase (HCS) catalyzes the binding of the vitamin biotin to carboxylases and histones. Carboxylases mediate essential steps in macronutrient metabolism. For example, propionyl- CoA carboxylase (PCC) catalyzes the carboxylation of propionyl-CoA in the metabolism of oddchain fatty acids. HCS comprises four putative domains, i.e., the N-terminus, the biotin transfer/ATP binding domain, a putative linker domain, and the C-terminus. Both N- and C-termini are essential for biotinylation of carboxylases by HCS, but the exact functions of these two domains in enzyme catalysis are unknown. Here we tested the hypothesis that N- and C-termini play roles in substrate recognition by HCS. …

X-Ray Spectroscopy Of The Radiation-Driven Winds Of Massive Stars: Line Profile And Line Ratio Diagnostics, David H. Cohen

Physics & Astronomy Faculty Works

Massive stars drive powerful, supersonic winds via the radiative momentum associated with the thermal UV emission from their photospheres. Shock phenomena are ubiquitous in these winds, heating them to millions, and sometimes tens of millions, of degrees. The emission line spectra from the shock-heated plasma provide powerful diagnostics of the winds' physical conditions, which in turn provide constraints on models of wind shock heating. Here I show how x-ray line transfer is affected by photoelectric absorption in the partially ionized component of the wind and how it can be modeled to determine the astrophysically important mass-loss rates of these stellar …

Common Carp Abundance, Biomass, And Removal From Dewey And Clear Lakes On The Valentine National Wildlife Refuge: Does Trapping And Removing Carp Payoff?, Greg A. Wanner, Melvin P. Nenneman, Mark A. Kaemingk

National Invasive Species Council

Common carp Cyprinus carpio is a nonnative invasive nuisance species to North America. Many authors have documented the detrimental affects of common carp invasions on waterfowl habitats (Chamberlain 1948; Robel 1961), game fish habitat (Cahn 1929), and the overall decline in native fishes (Bernstein and Olson 2001; Koehn 2004). Common carp reduce water quality by mobilizing nutrients and increasing turbidity; therefore, increasing phytoplankton biomass and reducing zooplankton biomass and rooted aquatic vegetation (Lougheed et al. 1998). Common carp are capable of rapidly colonizing shallow lakes and altering a body of water from a clear stable state, dominated by submergent vegetation …

Refuge Update – January/February 2009, Volume 6, Number 1

RefugeUpdate (USFWS-NWRS)

Table of Contents:
Fresh Thinking About Climate Change, page 3
Meet the New Refuge Chief, page 5
Focus on . . . Research on Refuges, pages 8-13
Drive. Dial. Discover., page 14

Search For Resonant Diphoton Production With The D0 Detector, V. M. Abazov, Kenneth A. Bloom, Gregory Snow, D0 Collaboration

Kenneth Bloom Publications

We present a search for a narrow resonance in the inclusive diphoton final state using ~2.7 fb^-1 of data collected with the D0 detector at the Fermilab Tevatron pp Collider.We observe good agreement between the data and the background prediction, and set the first 95% C.L. upper limits on the production cross section times the branching ratio for decay into a pair of photons for resonance masses between 100 and 150 GeV. This search is also interpreted in the context of several models of electroweak symmetry breaking with a Higgs boson decaying into two photons.