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2006

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Articles 5311 - 5340 of 5872

Full-Text Articles in Physical Sciences and Mathematics

Quantifying The Effects Of Correlated Covariates On Variable Importance Estimates From Random Forests, Ryan Vincent Kimes Jan 2006

Quantifying The Effects Of Correlated Covariates On Variable Importance Estimates From Random Forests, Ryan Vincent Kimes

Theses and Dissertations

Recent advances in computing technology have lead to the development of algorithmic modeling techniques. These methods can be used to analyze data which are difficult to analyze using traditional statistical models. This study examined the effectiveness of variable importance estimates from the random forest algorithm in identifying the true predictor among a large number of candidate predictors. A simulation study was conducted using twenty different levels of association among the independent variables and seven different levels of association between the true predictor and the response. We conclude that the random forest method is an effective classification tool when the goals …

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Bayesian Analysis, Endogenous Data,And Convergence Of Beliefs, Andrew T. Foerster Jan 2006

Bayesian Analysis, Endogenous Data,And Convergence Of Beliefs, Andrew T. Foerster

Theses and Dissertations

Problems in statistical analysis, economics, and many other disciplines often involve a trade-off between rewards and additional information that could yield higher future rewards. This thesis investigates such a trade-off, using a class of problems known as bandit problems. In these problems, a reward-seeking agent makes decisions based upon his beliefs about a parameter that controls rewards. While some choices may generate higher short-term rewards, other choices may provide information that allows the agent to learn about the parameter, thereby potentially increasing future rewards. Learning occurs if the agent's subjective beliefs about the parameter converge over time to the parameter's …

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Historical Glacier And Climate Fluctuations At Mount Hood, Oregon, Karl Lillquist, Karen Walker Jan 2006

Historical Glacier And Climate Fluctuations At Mount Hood, Oregon, Karl Lillquist, Karen Walker

Geography Faculty Scholarship

Terminus fluctuations of five glaciers and the correspondence of these fluctuations to temperature and precipitation patterns were assessed at Oregon's Mount Hood over the period 1901–2001. Historical photographs, descriptions, and climate data, combined with contemporary GPS measurements and GIS analysis, revealed that each glacier experienced overall retreat, ranging from −62 m at the Newton Clark Glacier to −1102 m at the Ladd Glacier. Within this overall trend, Mount Hood's glaciers experienced two periods each of retreat and advance. Glaciers retreated between 1901 and 1946 in response to rising temperatures and declining precipitation. A mid-century cool, wet period led to glacier …

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A Comparison For Longitudinal Data Missing Due To Truncation, Rong Liu Jan 2006

A Comparison For Longitudinal Data Missing Due To Truncation, Rong Liu

Theses and Dissertations

Many longitudinal clinical studies suffer from patient dropout. Often the dropout is nonignorable and the missing mechanism needs to be incorporated in the analysis. The methods handling missing data make various assumptions about the missing mechanism, and their utility in practice depends on whether these assumptions apply in a specific application. Ramakrishnan and Wang (2005) proposed a method (MDT) to handle nonignorable missing data, where missing is due to the observations exceeding an unobserved threshold. Assuming that the observations arise from a truncated normal distribution, they suggested an EM algorithm to simplify the estimation.In this dissertation the EM algorithm is …

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The Aeolian Flux Of Calcium, Chloride And Nitrate To The Mcmurdo Dry Valleys Landscape: Evidence From Snow Pit Analysis, Rebecca A. Witherow, W. Berry Lyons, Nancy A. Bertler, Kathleen A. Welch, Paul A. Mayewski, Sharon B. Sneed, Thomas H. Nylen, Michael J. Handley, Andrew G. Fountain Jan 2006

The Aeolian Flux Of Calcium, Chloride And Nitrate To The Mcmurdo Dry Valleys Landscape: Evidence From Snow Pit Analysis, Rebecca A. Witherow, W. Berry Lyons, Nancy A. Bertler, Kathleen A. Welch, Paul A. Mayewski, Sharon B. Sneed, Thomas H. Nylen, Michael J. Handley, Andrew G. Fountain

Geography Faculty Publications and Presentations

We have determined the flux of calcium, chloride and nitrate to the McMurdo Dry Valleys region by analysing snow pits for their chemical composition and their snow accumulation using multiple records spanning up to 48 years. The fluxes demonstrate patterns related to elevation and proximity to the ocean. In general, there is a strong relationship between the nitrate flux and snow accumulation, indicating that precipitation rates may have a great influence over the nitrogen concentrations in the soils of the valleys. Aeolian dust transport plays an important role in the deposition of some elements (e.g. Caý?) into the McMurdo Dry …

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Limits Of Diagonalization And The Polynomial Hierarchy, Kyle Barkmeier '06 Jan 2006

Limits Of Diagonalization And The Polynomial Hierarchy, Kyle Barkmeier '06

Honors Projects

Determining the computational complexity of problems is a large area of study. It seeks to separate these problems into ones with "efficient" solutions, and those with "inefficient" solutions. Of course, the strata is much more fine-grain than this. Of special interest are two classes of problems: P and NP. These have been of much interest to complexity theorists for quite some time, because both contain many instances of important real-world problems, and finding efficient solutions for those in NP would be beneficial for computing applications. Yet with all this attention, there are still important unanswered questions about the two classes. …

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An Euler-Type Formula For Ζ(2k +1), Tian-Xiao He, Michael Dancs Jan 2006

An Euler-Type Formula For Ζ(2k +1), Tian-Xiao He, Michael Dancs

Scholarship

In this short paper, we give several new formulas for ζ(n) when n is an odd positive integer. The method is based on a recent proof, due to H. Tsumura, of Euler’s classical result for even n. Our results illuminate the similarities between the even and odd cases, and may give some insight into why the odd case is much more difficult.

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Numerical Approximation To Ζ(2n+1), Tian-Xiao He, Michael Dancs Jan 2006

Numerical Approximation To Ζ(2n+1), Tian-Xiao He, Michael Dancs

Scholarship

In this short paper, we establish a family of rapidly converging series expansions ζ(2n +1) by discretizing an integral representation given by Cvijovic and Klinowski [3] in Integral representations of the Riemann zeta function for odd-integer arguments, J. Comput. Appl. Math. 142 (2002) 435–439. The proofs are elementary, using basic properties of the Bernoulli polynomials.

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On The Convergence Of The Summation Formulas Constructed By Using A Symbolic Operator Approach, Tian-Xiao He, Leetsch Hsu, Peter Shiue Jan 2006

On The Convergence Of The Summation Formulas Constructed By Using A Symbolic Operator Approach, Tian-Xiao He, Leetsch Hsu, Peter Shiue

Scholarship

This paper deals with the convergence of the summation of power series of the form Σa ≤ k ≤ bf(k)xk, where 0 ≤ a ≤ b < ∞, and {f(k)} is a given sequence of numbers with k ∈ [a, b) or f(t) a differentiable function defined on [a, b). Here, the summation is found by using the symbolic operator approach shown in [1]. We will give a different type of the remainder of the summation formulas. The convergence of the corresponding power series will be determined consequently. Several examples such as the generalized Euler's transformation series will also be given. In addition, we will compare the convergence of the given series transforms.

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On The Generalized Möbius Inversion Formulas, Tian-Xiao He, Peter Shiue3, Leetsch Hsu Jan 2006

On The Generalized Möbius Inversion Formulas, Tian-Xiao He, Peter Shiue3, Leetsch Hsu

Scholarship

We provide a wide class of M¨obius inversion formulas in terms of the generalized M¨obius functions and its application to the setting of the Selberg multiplicative functions.

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Spirobicyclic Diamines 1: Synthesis Of Proline-Derived Spirolactams Via Thermal Intramolecular Ester Aminolysis, Fintan Kelleher, Sinead Kelly Jan 2006

Spirobicyclic Diamines 1: Synthesis Of Proline-Derived Spirolactams Via Thermal Intramolecular Ester Aminolysis, Fintan Kelleher, Sinead Kelly

Articles

Proline derived [4.4]-spirolactams have been synthesised in good yields by a reductive-amination reaction followed by thermal cyclisation of the resulting amine onto the proline ester group in refluxing toluene. The synthesis of the corresponding [4.5]-spirolactams by the same method gave much reduced yields.

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Spirobicyclic Diamines 2: Synthesis Of Homochiral Diastereoisomeric Proline Derived [4,4]-Spirolactams, Fintan Kelleher, Sinead Kelly Jan 2006

Spirobicyclic Diamines 2: Synthesis Of Homochiral Diastereoisomeric Proline Derived [4,4]-Spirolactams, Fintan Kelleher, Sinead Kelly

Articles

L-Proline derived diastereoisomeric [4.4]-spirolactams have been prepared by a reductive-amination reaction of (R)- or (S)-alanine methyl ester followed by thermal cyclisation of the resulting amine onto the proline ester group in refluxing toluene. Under similar conditions (R)- or (S)-phenylalanine methyl ester gave no cyclisation products, while R- or S-a-methylbenzylamine required treatment with NaNH2 in refluxing toluene to induce cyclisation giving diastereoisomeric [4.4]-spirolactams

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Plasma Emission Redistribution In A Single Cylce Of A Pulsed Dc Magnetron, W. Zhu, G. Buyle, J. Lopez, S. Shanmugmurthy, A. Belkind, K. Becker, R. De Gryse Jan 2006

Plasma Emission Redistribution In A Single Cylce Of A Pulsed Dc Magnetron, W. Zhu, G. Buyle, J. Lopez, S. Shanmugmurthy, A. Belkind, K. Becker, R. De Gryse

Physics Faculty Publications

Time-resolved images of the optical emissions from a pulsed dc titanium target planar rectangular sputtering magnetron plasma were taken using Argon spectral filters and a Roper Scientific ICCD camera with a time resolution of 0.05-0.2 μs. At the beginning of the 'on-time', when the power is turned on, the discharge initially starts preferentially in two opposite curved sections ('cross corners') of the magnetron race track, where it exhibits the most intense plasma emissions. During the rest of the 'on-time', the emissions from the straight sections of the race track of the magnetron are always slightly more intense than the emissions …

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Diffuse Light Scattering Dynamics Under Conditions Of Electromagnetically Induced Transparency, V. M. Datsyuk, I. M. Sokolov, D. V. Kupriyanov, M. D. Havey Jan 2006

Diffuse Light Scattering Dynamics Under Conditions Of Electromagnetically Induced Transparency, V. M. Datsyuk, I. M. Sokolov, D. V. Kupriyanov, M. D. Havey

Physics Faculty Publications

We show that under conditions of electromagnetically induced transparency (EIT) in an ultracold atomic sample in a magneto-optical trap, a significant portion of the incident probe pulse is transferred into Rayleigh and Raman scattering channels. The light scattered into the Rayleigh channel emerges from the sample with an EIT time delay. We show that a proper description of the probe light propagation in the sample should include, in the diffusion dynamics, a spin polariton generated by the two-photon EIT process. The results have important implications for studies of weak light localization and for manipulation of single and few photon states …

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Erratum: Η' Photoproduction On The Proton For Photon Energies From 1.527 To 2.227 Gev (Phys. Rev. Lett. 96, Pg 062001, 2006), H. Bagdasaryan, M. Bektasoglu, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, A. Klein, S. E. Kuhn, L. M. Qin, F. Sabatié, L. B. Weinstein, Et Al., Clas Collaboration Jan 2006

Erratum: Η' Photoproduction On The Proton For Photon Energies From 1.527 To 2.227 Gev (Phys. Rev. Lett. 96, Pg 062001, 2006), H. Bagdasaryan, M. Bektasoglu, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, A. Klein, S. E. Kuhn, L. M. Qin, F. Sabatié, L. B. Weinstein, Et Al., Clas Collaboration

Physics Faculty Publications

No abstract provided.

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Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay Jan 2006

Petrography And Geochemistry Of Paragneisses In The Çine Submassif Of The Menderes Massif, Western Anatolia, Firat Şengün, Osman Candan, O. Özcan Dora, O. Ersi̇n Koralay

Turkish Journal of Earth Sciences

The Menderes Massif, which covers a large area in western Turkey, is made up of Pan-African basement rocks and a Palaeozoic to Early Tertiary cover sequence. The study area is located in the Dalama and Hallaçlar (Aydın) area, in the northern and central parts of the Çine submassif of the Menderes Massif. The oldest units of the Pan-African basement are metaclastics, consisting of paragneisses and mica schists that gradually and conformably overlay paragneisses. Macroscopic appearances and mineralogical and textural data indicate that paragneisses can be subdivided into four subgroups. These are: (1) black spotted, (2) white spotted, (3) massive, grey-coloured …

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Investigation Of Water Masses In İzmir Bay, Western Turkey, Erdem Sayin, İdi̇l Pazi, Canan Eronat Jan 2006

Investigation Of Water Masses In İzmir Bay, Western Turkey, Erdem Sayin, İdi̇l Pazi, Canan Eronat

Turkish Journal of Earth Sciences

The main purpose of this paper is to explore seasonal variability of the local hydrography and investigate the water masses, their seasonal and regional variations in the vicinity of İzmir Bay based on data sets collected between 1994 and 2003. The general water movement characteristics in the bay are provided by CTD data analysis together with Killworth's general circulation model. In the bay, three distinct water masses exist: ASW (Aegean Sea water), IBW (İzmir Bay water) and IBIW (İzmir Bay inner water). Generally, vertically homogenous ASW enters the bay from the north, near Karaburun in winter, and horizontally homogeneous ASW …

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Contact Metamorphism Around The Eocene Saraycık Granodiorite, Eastern Pontides, Turkey, Gülteki̇n Topuz Jan 2006

Contact Metamorphism Around The Eocene Saraycık Granodiorite, Eastern Pontides, Turkey, Gülteki̇n Topuz

Turkish Journal of Earth Sciences

The Eocene Saraycık granodiorite, eastern Pontides, Turkey, is a small post-tectonic intrusive body (~11 km2), cross-cutting tectonically juxtaposed distinct metamorphic and non-metamorphic lithologies. A ~0.8 to 1-km-wide contact-metamorphic aureole has developed around the intrusion. Disequilibrium is prevalent in all lithologies, even in the inner zones of the contact aureole. Conditions of contact metamorphism are estimated by simple phase equilibria applied to microdomains in the metapelitic lithologies without obvious signs of disequilibrium: Shallow emplacement depths (0.21±0.05 GPa = ~5-8 km) are suggested by contact-metamorphic mineral assemblages (e.g., andalusite + corundum + K-feldspar), by Al-in-hornblende barometry on granodiorite and by partial melting …

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Stratigraphic And Palaeoenvironmental Significance Of Bartonian–Priabonian (Middle–Late Eocene) Microfossils From The Başçeşme Formation, Denizli Province, Western Anatolia, M. Serkan Akki̇raz, Funda Akgün, Sefer Örçen, Angela Bruch, Volker Mosbrugger Jan 2006

Stratigraphic And Palaeoenvironmental Significance Of Bartonian–Priabonian (Middle–Late Eocene) Microfossils From The Başçeşme Formation, Denizli Province, Western Anatolia, M. Serkan Akki̇raz, Funda Akgün, Sefer Örçen, Angela Bruch, Volker Mosbrugger

Turkish Journal of Earth Sciences

This study explains the stratigraphical and palaeoenvironmental significance of Bartonian-Priabonian (Middle-Late Eocene) fossils, the fauna and flora obtained from the Başçeşme formation of the Çardak-Tokça basin (western Anatolia). The studied sequence is an outcrop from the Başçeşme formation, deposited in a shallow-marine to coastal environment without stratigraphic breaks. Forty genera and 58 species have been recognized in the palynological assemblage of the Başçeşme formation. A well-preserved diverse palynomorph and foraminiferal assemblages yield the Middle-Late Eocene age for the Başçeşme formation. In western Anatolia, mangrove elements Nypa and Pelliciera have been first recorded in this study. The pollen of Mauritia and …

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Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari Jan 2006

Calcretized Ferricretes Around The Jaisalmer Area, Thar Desert, India: Their Chemistry, Mineralogy, Micromorphology And Genesis, D. Ramakrishnan, Krishna Chandra Tiwari

Turkish Journal of Earth Sciences

Ferricrete, an iron duricrust, caps Tertiary and Mesozoic rocks around Jaisalmer in the Indian desert. These ferricretes are associated with two distinct present-day landforms. The upper unit is a high-level dissected, rocky structural plain and the lower one a colluvial flat with soft ferricrete gravels. This study pertains to the first situation wherein field observations, micromorphological features and regolith chemistry suggest an in situ origin for the ferricretes, as in the case of the Walther profile. Subsequent tectonism and changes in base level resulted in a shift in processes from weathering to erosion. Episodes of erosion resulted in inversion of …

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Mineral-Chemical Constraints On The Miocene Calc-Alkaline And Shoshonitic Volcanic Rocks Of Western Turkey: Disequilibrium Phenocryst Assemblages As Indicators Of Magma Storage And Mixing Conditions, Ercan Aldanmaz Jan 2006

Mineral-Chemical Constraints On The Miocene Calc-Alkaline And Shoshonitic Volcanic Rocks Of Western Turkey: Disequilibrium Phenocryst Assemblages As Indicators Of Magma Storage And Mixing Conditions, Ercan Aldanmaz

Turkish Journal of Earth Sciences

Early to Middle Miocene (22 to 15 Ma) volcanic activity across western Turkey produced a series of lavas and pyroclastic deposits with calc-alkaline and shoshonitic affinities. The erupted magmas show a broad range of compositions from basaltic to rhyolitic (48-75 SiO2 wt%) and are composed of variable phenocryst assemblages. Petrographic and mineral-chemical characteristics suggest that the magmas underwent hydrous crystallization in deep crustal magma chambers that was dominated by plagioclase + pyroxene + pargasitic amphibole fractionation. Subsequent crystallization in shallower magma chambers followed two different trends: (1) anhydrous (pyroxene + plagioclase-dominated); and (2) hydrous (plagioclase + edenitic amphibole + pyroxene-dominated). …

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Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu Jan 2006

Geochemical Constraints On The Provenance, Mineral Sorting And Subaerial Weathering Of Lower Jurassic And Upper Cretaceous Clastic Rocks Of The Eastern Pontides, Yusufeli (Artvin), Ne Turkey, Abdurrahman Dokuz, Erkan Tanyolu

Turkish Journal of Earth Sciences

An integrated petrographic and geochemical study of the shales and sandstones of Early Jurassic and Late Cretaceous age in the Yusufeli area (Turkey) was carried out to obtain more information on their provenance, sedimentological history and tectonic setting, as well as to evaluate the influence of weathering, hydraulic sorting and recycling processes upon source-rock signature. Depending on their matrix and mineralogical content, the Lower Jurassic sandstones are identified as arkosic arenite and wacke, while the Upper Cretaceous sandstones are defined as lithic arenite and wacke. Elemental ratios such as La/Sc, Cr/Ni, Co/Th, Th/Sc and Cr/Th indicate a mafic source for …

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Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça Jan 2006

Palynomorph, Foraminifera, And Calcareous Nannoplankton Biostratigraphy Of Oligo–Miocene Sediments In The Muş Basin, Eastern Anatolia, Turkey, Recep Hayretti̇n Sancay, Zühtü Bati, Uğraş Işik, Sabri̇ Kirici, Ni̇hal Akça

Turkish Journal of Earth Sciences

Oligo-Miocene sediments have not been adequately studied biostratigraphically, and a detailed bio-chronostratigraphic framework has not yet been established in Eastern Anatolian basins. Palynomorphs have therefore been correlated with the biozonations of marine dinoflagellates, planktonic foraminifera and calcareous nannoplankton of similar latitudes in combined samples from the Ebulbahar and Kelereşdere measured stratigraphic sections, which are located in the northeastern part of Muş. Palynological (dinoflagellate), foraminiferal micropalaentological, and nannopalaeontological events, correlatable with worldwide defined biozonations, have been documented from uppermost Rupelian to Upper Miocene-Pliocene sediments. First occurrences (FOs) and and last occurrences (LOs) of selected dinoflagellates are important in establishing the biostratigraphic …

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Reply To Comment On ‘Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing’, Zafer Arslan Jan 2006

Reply To Comment On ‘Petrography And Petrology Of The Calc-Alkaline Sarıhan Granitoid (Ne Turkey): An Example Of Magma Mingling And Mixing’, Zafer Arslan

Turkish Journal of Earth Sciences

No abstract provided.

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Reply To Comment By Cristina Archer And Mark Jacobson On ‘‘Evaluation Of A Wind Power Parameterization Using Tower Observations’’, Steven Lazarus, Jennifer Bewley Jan 2006

Reply To Comment By Cristina Archer And Mark Jacobson On ‘‘Evaluation Of A Wind Power Parameterization Using Tower Observations’’, Steven Lazarus, Jennifer Bewley

Ocean Engineering and Marine Sciences Faculty Publications

The Lazarus and Bewley [2005] (hereinafter referred to as LB05) evaluation of the Archer and Jacobson [2003] (hereinafter referred to as AJ03) methodology was designed to examine various sensitivities of a wind power parameterization that was applied globally to estimate 80-m wind power. AJ03 has since been updated in a sequence of papers which has, in part, resulted in a reduction of their original power estimates due to some changes in their basic equations. The motivation for the LB05 work can be found in AJ03’s Figure 3 which indicates annual wind power estimates of class 6 and 7 effectively collocated …

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Transport Of Spring Floodwater From Rivers Under Ice To The Alaskan Beaufort Sea, Matthew B. Alkire, John H. Trefry Jan 2006

Transport Of Spring Floodwater From Rivers Under Ice To The Alaskan Beaufort Sea, Matthew B. Alkire, John H. Trefry

Ocean Engineering and Marine Sciences Faculty Publications

Spring floods carry Alaskan river water north to a frozen Beaufort Sea. A plume of water from the Sagavanirktok River (SR) was identified and traced by measuring salinity, d18O, and dissolved silica in discrete water samples collected beneath landfast ice in the coastal Alaskan Beaufort Sea from late May to early June 2004 during high river flow. An Optimum Multiparameter analysis was used to calculate the fractions of SR water from the measured geochemical parameters. The SR plume followed the northwestward flowing local circulation and moved ~17 km north and ~15 km west under ice from the river mouth. The …

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Plant Paleoecology Of The Late Devonian Red Hill Locality, North-Central Pennsylvania, An Archaeopteris-Dominated Wetland Plant Community And Early Tetrapod Site., Walter L. Cressler Iii Jan 2006

Plant Paleoecology Of The Late Devonian Red Hill Locality, North-Central Pennsylvania, An Archaeopteris-Dominated Wetland Plant Community And Early Tetrapod Site., Walter L. Cressler Iii

Earth & Space Sciences Faculty Publications

The Late Devonian Red Hill locality in north-central Pennsylvania contains an Archaeopteris-dominated plant fossil assemblage, a diverse fossil fauna, and an extensive sedimentary sequence ideal for investigating the landscapes and biotic associations of the earliest forest ecosystems. Sedimentological analysis of the main plantfossil bearing layer at Red Hill indicates that it was a fl ood-plain pond. A seasonal wet-and-dry climate is indicated by well-developed paleovertisols. The presence of charcoal interspersed with plant fossils indicates that fi res occurred in this landscape.Fires appear to have primarily affected the fern Rhacophyton. The specifi city of the fires, the distribution profi …

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Shuffle Up And Deal: Should We Have Jokers Wild?, Kristen Lampe Jan 2006

Shuffle Up And Deal: Should We Have Jokers Wild?, Kristen Lampe

Undergraduate Mathematics Day: Past Content

In the neighborhood poker games, one often hears of adding the Jokers as wild cards, or declaring deuces wild. In this talk, we’ll explore what happens mathematically when two Jokers are added to the deck. The probabilities for different hands change, in ways that might surprise you. Further, we will explore the mathematical consequences of playing poker with more or fewer than five cards. Finally, we will look at the historical beginnings of poker, and a mathematical anomaly that occurred along the way.

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Verification Of Direct Brachytherapy Dosimetry For A Single Seed Implant, Jabari Robinson Jan 2006

Verification Of Direct Brachytherapy Dosimetry For A Single Seed Implant, Jabari Robinson

LSU Master's Theses

A new technique using direct post-implant dosimetry, which does not depend explicitly on brachytherapy seed orientation or position, was explored for a prostate and a breast case. This technique, proposed by E Sajo and ML Williams (SW), uses trace amounts of positron emitters placed in the seed capsule and uses the positron emission tomography image in conjunction with a computed tomography image (PET-CT) to compute the therapeutic dose distribution in the patient. The SW technique could reduce errors in the post-implant dose computations associated with seed localization, seed shadowing and medium heterogeneity. Dose point kernels were obtained using Monte Carlo …

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Reliability Of Determining Adults From Juvenile Ducks By Presence Or Absence Of Notched Tail Feathers In Various Species Of North American Ducks, Thomas Michael Siwarski Jan 2006

Reliability Of Determining Adults From Juvenile Ducks By Presence Or Absence Of Notched Tail Feathers In Various Species Of North American Ducks, Thomas Michael Siwarski

LSU Master's Theses

I estimated when juvenile tail molt occurs for several commonly harvested duck species, mallards (Anas platyrhynchos), northern pintails (A. acuta) (hereafter referred to as pintails), gadwalls (A. strepera), lesser scaup (Aythya affinis), and redheads (A. americana). Tests showed that aging mallards by notched tail feathers became unreliable the earliest (early September), followed closely by pintails (mid-late September), with gadwalls being the latest of the dabbling ducks to lose reliability in aging by notched tail feathers (late November). Lesser scaup and redheads retained their notched tail feathers throughout January and the completion of hunting season. Based on initial banding and band …

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