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Articles 421 - 450 of 3876
Full-Text Articles in Physical Sciences and Mathematics
Development Of A Mechanistic Understanding Of High-Temperature Deformation Of Alloy Ep-823 For Transmutation Applications: Annual Progress Report (September 2002 – August 2003), Ajit K. Roy, Brendan O'Toole
Development Of A Mechanistic Understanding Of High-Temperature Deformation Of Alloy Ep-823 For Transmutation Applications: Annual Progress Report (September 2002 – August 2003), Ajit K. Roy, Brendan O'Toole
Transmutation Sciences Materials (TRP)
The purpose of this project is to evaluate the elevated temperature tensile properties of Alloy EP-823, a leading structural target material for accelerator-driven waste transmutation applications. This alloy has been proven to be an excellent structural material to contain the molten lead-bismuth-eutectic (LBE) nuclear coolant needed for fast spectrum operations. Very little data exist in the open literature on the tensile properties of this martensitic alloy. Three different heats of this material, produced by vacuum induction melting, were thermally treated to produce fully-tempered martensitic microstructure without any retained austenite (Table I). Cylindrical specimens were fabricated from the heat-treated round bars …
Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix, Spencer M. Steinberg, David W. Emerson, Gary Cerefice
Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix, Spencer M. Steinberg, David W. Emerson, Gary Cerefice
Separations Campaign (TRP)
The recovery of iodine released during the processing of used nuclear fuel poses a significant challenge to the transmutation of radioactive iodine. During the first year of this program we have examined the potential of Fullerene Containing Carbon compounds (FCC) developed by KRI, and natural organic matter (NOM) as sorbents for iodine released during the reprocessing of nuclear fuel. This work involved the development of bench-scale testing of the FCC and NOM material in a simulated process off-gas environment.
During the first two quarters of this program we explored various analytical methods available for measurement of iodine, iodide, and iodate. …
Statistical Inferences Based On Non-Smooth Estimating Functions, Lu Tian, Jun S. Liu, Mary Zhao, L. J. Wei
Statistical Inferences Based On Non-Smooth Estimating Functions, Lu Tian, Jun S. Liu, Mary Zhao, L. J. Wei
Harvard University Biostatistics Working Paper Series
No abstract provided.
Chemical Composition Of Asian Continental Outflow Over The Western Pacific: Results From Transport And Chemical Evolution Over The Pacific (Trace-P), R. S. Russo, R. Talbot, Jack E. Dibb, Eric Scheuer, Garry Seid, C. Jordan, H Fuelberg, G W. Sachse, M A. Avery, S Vay, D R. Blake, N J. Blake, E L. Atlas, A Fried, S T. Sandholm, D Tan, H B. Singh, J Snow, B J. Heikes
Chemical Composition Of Asian Continental Outflow Over The Western Pacific: Results From Transport And Chemical Evolution Over The Pacific (Trace-P), R. S. Russo, R. Talbot, Jack E. Dibb, Eric Scheuer, Garry Seid, C. Jordan, H Fuelberg, G W. Sachse, M A. Avery, S Vay, D R. Blake, N J. Blake, E L. Atlas, A Fried, S T. Sandholm, D Tan, H B. Singh, J Snow, B J. Heikes
Earth Sciences
We characterize the chemical composition of Asian continental outflow observed during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) mission during February–April 2001 in the western Pacific using data collected on the NASA DC-8 aircraft. A significant anthropogenic impact was present in the free troposphere and as far east as 150°E longitude reflecting rapid uplift and transport of continental emissions. Five-day backward trajectories were utilized to identify five principal Asian source regions of outflow: central, coastal, north-northwest (NNW), southeast (SE), and west-southwest (WSW). The maximum mixing ratios for several species, such as CO, C2Cl4, …
Large-Scale Ozone And Aerosol Distributions, Air Mass Characteristics, And Ozone Fluxes Over The Western Pacific Ocean In Late Winter/Early Spring, Edward V. Browell, Marta Fenn, Carolyn Butler, William B. Grant, Vincent G. Brackett, Jonathan Hair, Melody A. Avery, Yuanlong Hu, Reginald E. Newell, H Fuelberg, Daniel J. Jacob, Bruce E. Anderson, Elliot Atlas, D R. Blake, William H. Brune, Jack E. Dibb, A Fried, B J. Heikes, G W. Sachse, S T. Sandholm, Hanwant B. Singh, R. Talbot, S Vay, Rodney J. Weber, Karen B. Bartlett
Large-Scale Ozone And Aerosol Distributions, Air Mass Characteristics, And Ozone Fluxes Over The Western Pacific Ocean In Late Winter/Early Spring, Edward V. Browell, Marta Fenn, Carolyn Butler, William B. Grant, Vincent G. Brackett, Jonathan Hair, Melody A. Avery, Yuanlong Hu, Reginald E. Newell, H Fuelberg, Daniel J. Jacob, Bruce E. Anderson, Elliot Atlas, D R. Blake, William H. Brune, Jack E. Dibb, A Fried, B J. Heikes, G W. Sachse, S T. Sandholm, Hanwant B. Singh, R. Talbot, S Vay, Rodney J. Weber, Karen B. Bartlett
Earth Sciences
Large-scale measurements of ozone (O3) and aerosol distributions were made from the NASA DC-8 aircraft during the Transport and Chemical Evolution over the Pacific (TRACE-P) field experiment conducted in February–April 2001. Remote measurements were made with an airborne lidar to provide O3 and multiple-wavelength aerosol backscatter profiles from near the surface to above the tropopause along the flight track. In situ measurements of O3, aerosols, and a wide range of trace gases were made onboard the DC-8. Five-day backward trajectories were used in conjunction with the O3 and aerosol distributions on each flight to …
Reactive Nitrogen In Asian Continental Outflow Over The Western Pacific: Results From The Nasa Transport And Chemical Evolution Over The Pacific (Trace-P) Airborne Mission, R. Talbot, Jack E. Dibb, Eric Scheuer, Garry Seid, R. S. Russo, S T. Sandholm, D Tan, H B. Singh, D R. Blake, N J. Blake, Elliot Atlas, G W. Sachse, C. Jordan, Melody A. Avery
Reactive Nitrogen In Asian Continental Outflow Over The Western Pacific: Results From The Nasa Transport And Chemical Evolution Over The Pacific (Trace-P) Airborne Mission, R. Talbot, Jack E. Dibb, Eric Scheuer, Garry Seid, R. S. Russo, S T. Sandholm, D Tan, H B. Singh, D R. Blake, N J. Blake, Elliot Atlas, G W. Sachse, C. Jordan, Melody A. Avery
Earth Sciences
We present here results for reactive nitrogen species measured aboard the NASA DC-8 aircraft during the Transport and Chemical Evolution over the Pacific (TRACE-P) mission. The large-scale distributions total reactive nitrogen (NOy,sum = NO + NO2 + HNO3 + PAN + C1–C5alkyl nitrates) and O3 and CO were better defined in the boundary layer with significant degradation of the relationships as altitude increased. Typically, NOy,sum was enhanced over background levels of ∼260 pptv by 20-to-30-fold. The ratio C2H2/CO had values of 1–4 at altitudes up to 10 …
Summary Of Measurement Intercomparisons During Trace-P, Fred Eisele, Lee Mauldin, C A. Cantrell, M Zondlo, E C. Apel, A Fried, J Walega, R E. Shetter, Barry Lefer, F Flocke, Andrew Weinheimer, M A. Avery, S Vay, G W. Sachse, J Podolske, G S. Diskin, J D. Barrick, H B. Singh, William H. Brune, H Harder, M Martinez, A R. Bandy, D C. Thornton, B J. Heikes, Y Kondo, D Riemer, S T. Sandholm, R. Talbot, Jack E. Dibb
Summary Of Measurement Intercomparisons During Trace-P, Fred Eisele, Lee Mauldin, C A. Cantrell, M Zondlo, E C. Apel, A Fried, J Walega, R E. Shetter, Barry Lefer, F Flocke, Andrew Weinheimer, M A. Avery, S Vay, G W. Sachse, J Podolske, G S. Diskin, J D. Barrick, H B. Singh, William H. Brune, H Harder, M Martinez, A R. Bandy, D C. Thornton, B J. Heikes, Y Kondo, D Riemer, S T. Sandholm, R. Talbot, Jack E. Dibb
Earth Sciences
The NASA DC-8 and P-3B aircraft flew within about a kilometer or less of each other on three occasions during the Transport and Chemical Evolution Over the Pacific (TRACE-P) campaign in order to intercompare similar measurements on the two aircraft. The first and last intercomparisons were in relatively remote marine environments during transits to and from Asia. The first began with a boundary layer measurement followed by an ascent to 3 km. The second set of intercomparisons was at a fixed altitude of about 5.2 km off the coast of Japan, also in relatively clean air. Finally, the third measurement …
Late-Holocene Lake-Level Variation In West Greenland, Frank A. Aebly, Sherilyn C. Fritz
Late-Holocene Lake-Level Variation In West Greenland, Frank A. Aebly, Sherilyn C. Fritz
Department of Earth and Atmospheric Sciences: Faculty Publications
Situated between the North Atlantic and the Greenland ice sheet, the thousands of lakes in the Kangerlussuaq area of West Greenland (67°N) present excellent targets for paleoclimate studies. Paleoshorelines surrounding multiple closed-basin lakes in this area record fluctuations in lake level since deglaciation. Shorelines along two of these lakes, Hundeso and Lake E, were surveyed and trenched to reconstruct the history of lake-level change. The stratigraphies of the trenches were described, and a chronology has been developed using radiocarbon dating of organic material. Preliminary results indicate a highly variable hydrologic regime throughout the late Holocene.
Hundeso had high-stand lake levels …
Measurement Of Conductivity And Charge Storage In Insulators Related To Spacecraft Charging, A. R. Frederickson, Jr Dennison
Measurement Of Conductivity And Charge Storage In Insulators Related To Spacecraft Charging, A. R. Frederickson, Jr Dennison
Conference Proceedings
Several methods have been combined to measure conductivity and charge storage in insulating spacecraft materials. In order to avoid insulator problems, the motions of conducting electrons and holes must prevent the development of large electric fields exceeding 1E5 V/cm, where problems occur in spacecraft insulators. Approximate knowledge of the electric fields is important. One must consider generation of mobile electrons and holes, their trapping, thermal de-trapping, mobility and recombination.
Classical methods to measure thin film insulator conductivity apply a constant voltage to two electrodes on the sample and measure the resulting current for tens of minutes. Under constant voltage, a …
Elucidating The Mechanisms Of Double Ionization Using Intense Half-Cycle, Single-Cycle, And Double Half-Cycle Pulses, G. Lagmago Kamta, Anthony F. Starace
Elucidating The Mechanisms Of Double Ionization Using Intense Half-Cycle, Single-Cycle, And Double Half-Cycle Pulses, G. Lagmago Kamta, Anthony F. Starace
Department of Physics and Astronomy: Faculty Publications
We investigate the interaction of a two-active electron system (Li-) with intense single-cycle and double half-cycle pulses. The ‘‘intensity’’ and ‘‘frequency’’ considered correspond to the ‘‘multiphoton above-barrier regime.’’ For the single-cycle pulse (SCP), the electric field changes sign once, allowing electron wave packets created during the first half cycle to recollide with the parent ion when driven back by the field. For the double half-cycle pulse (DHP), however, the electric field does not change sign, and electron wave packets created during the first half cycle are not driven back to the parent ion. We find that both single …
Fading Characteristics For Indoor Wireless Channels At 5 Ghz Unlicensed Bands, M. Carroll, Tadeusz A. Wysocki
Fading Characteristics For Indoor Wireless Channels At 5 Ghz Unlicensed Bands, M. Carroll, Tadeusz A. Wysocki
Faculty of Informatics - Papers (Archive)
The paper reports on experiments undertaken at the University of Wollongong to characterise fading profiles of indoor wireless channels at the 5 GHz bands. The measurements were undertaken at different locations around the campus with results recorded for post-processing to calculate the Rician k-factor, the level crossing rate and the average fade duration.
Rust, Glue, And Molecules -- Understanding The Role Of Molecular Structure On Macroscopic Interfacial Properties, Mark Anderson
Rust, Glue, And Molecules -- Understanding The Role Of Molecular Structure On Macroscopic Interfacial Properties, Mark Anderson
Mark R. Anderson
No abstract is available at this time.
Measurement Of The Mass Difference M(DS+)–M (D+) At Cdf Ii, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Measurement Of The Mass Difference M(DS+)–M (D+) At Cdf Ii, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We present a measurement of the mass difference m(Ds+)– m (D+), where both the Ds+ and D+ are reconstructed in the Φπ+ decay channel. This measurement uses 11.6 pb-1 of data collected by CDF II using the new displaced-track trigger. The mass difference is found to be m(Ds+)–m (D+)=99.41±0.38(stat)±0.21(syst) MeV/c2.
On The Cox Model With Time-Varying Regression Coefficients, Lu Tian, David Zucker, L. J. Wei
On The Cox Model With Time-Varying Regression Coefficients, Lu Tian, David Zucker, L. J. Wei
Harvard University Biostatistics Working Paper Series
No abstract provided.
Pyridoxamine Traps Intermediates In Lipid Peroxidation Reactions In Vivo: Evidence On The Role Of Lipids In Chemical Modification Of Protein And Development Of Diabetic Complications, Thomas O. Metz, Nathan L. Alderson, Mark E. Chachich, Suzanne R. Thorpe, John W. Baynes
Pyridoxamine Traps Intermediates In Lipid Peroxidation Reactions In Vivo: Evidence On The Role Of Lipids In Chemical Modification Of Protein And Development Of Diabetic Complications, Thomas O. Metz, Nathan L. Alderson, Mark E. Chachich, Suzanne R. Thorpe, John W. Baynes
Faculty Publications
Maillard or browning reactions between reducing sugars and protein lead to formation of advanced glycation end products (AGEs) and are thought to contribute to the pathogenesis of diabetic complications. AGE inhibitors such as aminoguanidine and pyridoxamine (PM) inhibit both the formation of AGEs and development of complications in animal models of diabetes. PM also inhibits the chemical modification of protein by advanced lipoxidation end products (ALEs) during lipid peroxidation reactions in vitro. We show here that several PM adducts, formed in incubations of PM with linoleate and arachidonate in vitro, are also excreted in the urine of PM-treated animals. The …
Search For Lepton Flavor Violating Decays Of A Heavy Neutral Particle In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Search For Lepton Flavor Violating Decays Of A Heavy Neutral Particle In Pp̅ Collisions At √S =1.8 Tev, Darin Acosta, Kenneth A. Bloom, Collider Detector At Fermilab Collaboration
Kenneth Bloom Publications
We report on a search for a high mass, narrow width particle that decays directly to eµ, eτ, or µτ. We use approximately 110 pb-1 of data collected with the Collider Detector at Fermilab from 1992 to 1995. No evidence of lepton flavor violating decays is found. Limits are set on the production and decay of sneutrinos with R-parity violating interactions.
Ordering Tendencies In Octahedral Mgo-Zno Alloys, Gus L. W. Hart, Mahdi Sanati, Alex Zunger
Ordering Tendencies In Octahedral Mgo-Zno Alloys, Gus L. W. Hart, Mahdi Sanati, Alex Zunger
Faculty Publications
Isostrutural II-VI alloys whose components are either rocksalt stable (e.g., CaO-MgO) or zincblende stable (e.g., ZnS-ZnSe) are known to be thermodynamically unstable at low temperatures, showing a miscibility gap and no bulk ordering. In contrast, we show that heterostructural MgO-ZnO is stable, under certain conditions, in the sixfold-coordinated structure for Zn concentrations below 67%, giving rise to spontaneously ordered alloys. Using first-principles calculations, we explain the origin of this stability, the structures of their low-temperature ordered phases, short-range-order patterns, and their optical band-gap properties.
Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 August 2002 - 31 August 2003, Philip W. Sadler, Robert J. Latour, Robert E. Harris, Julia Ellis, John E. Olney
Evaluation Of Striped Bass Stocks In Virginia, Monitoring And Tagging Studies, 1999-2003 Annual Report, 1 August 2002 - 31 August 2003, Philip W. Sadler, Robert J. Latour, Robert E. Harris, Julia Ellis, John E. Olney
Reports
This report presents the results of striped bass (Marone saxatilis) tagging and monitoring activities in Virginia during the period 1 August 2002 through 31 August 2003. It includes an assessment ofthe biological characteristics of striped bass taken from the 2003 spring spawning run, estimates of annual survival based on annual spring tagging, and the results ofthe fall2002 directed mortality study that is cooperative with the Maryland Department of Natural Resources. The information contained in this report is required by the Atlantic States Marine Fisheries Commission and is used to implement a coordinated management plan for striped bass in Virginia, and …
Redox Scale For Assigning An Oxidizing/Reducing Potential To Groundwater: Method Development And Initial Results, Julie Bertoia, Vernon Hodge, Klaus J. Stetzenbach, Amy J. Smiecinski
Redox Scale For Assigning An Oxidizing/Reducing Potential To Groundwater: Method Development And Initial Results, Julie Bertoia, Vernon Hodge, Klaus J. Stetzenbach, Amy J. Smiecinski
Publications (YM)
This report outlines the progress on Task 33 of the Department of Energy's Yucca Mountain Cooperative Agreement with the University and Community College System of Nevada (UCCSN). The task is titled "The Experimental Determination of a "Redox Scale" for Assigning an Oxidizing/Reducing Potential to Groundwater from Wells in the Nye County Early Warning Drilling Program: A Scale for Predicting the Solubility and Mobility of Elements Commonly Found in Nuclear Wastes". The purpose of the research was to determine the concentrations of the various electrochemical oxidation states or redox species of eleven elements in groundwater samples collected from the Nye County …
Hygroscopic Growth Of Ammonium Sulfate/Dicarboxylic Acids, Matthew E. Wise, Jason D. Surratt, Daniel B. Curtis, John E. Shilling, Margaret A. Tolbert
Hygroscopic Growth Of Ammonium Sulfate/Dicarboxylic Acids, Matthew E. Wise, Jason D. Surratt, Daniel B. Curtis, John E. Shilling, Margaret A. Tolbert
CUP Faculty Research
Recent studies have shown that tropospheric sulfate aerosols commonly contain 50% by mass organic species. The influence of these organics on the chemical and physical properties of sulfate aerosols is not fully established. We have measured the water activity of pure dicarboxylic acids and eutonic mixtures of ammonium sulfate/dicarboxylic acids at 25°C and have calculated van't Hoff factors for each individual system. We have also used the vapor pressure data to determine the hygroscopic growth curves for pure dicarboxylic acids and eutonic mixtures and provide power law fits to the data. For the systems studied we find that the presence …
Electrochemical Preparation Of Chitosan/Hydroxyapatite Composite Coatings On Titanium Substrates, Jody G. Redepenning, Guhanand Venkataraman, Jun Chen, Nathan Stafford
Electrochemical Preparation Of Chitosan/Hydroxyapatite Composite Coatings On Titanium Substrates, Jody G. Redepenning, Guhanand Venkataraman, Jun Chen, Nathan Stafford
Jody Redepenning Publications
Composite coatings containing brushite (CaHPO4 • 2H2O) and chitosan were prepared by electrochemical deposition. The brushite/chitosan composites were converted to hydroxyapatite/chitosan composites in aqueous solutions of sodium hydroxide. The coatings ranged from 1 to 15% chitosan by weight. Qualitative assessment of the coatings showed adhesion signifi cantly improved over that observed for electrodeposited coatings of pure HA.
Sylvester: Ushering In The Modern Era Of Research On Odd Perfect Numbers, Steven Gimbel, John Jaroma
Sylvester: Ushering In The Modern Era Of Research On Odd Perfect Numbers, Steven Gimbel, John Jaroma
Philosophy Faculty Publications
In 1888, James Joseph Sylvester (1814-1897) published a series of papers that he hoped would pave the way for a general proof of the nonexistence of an odd perfect number (OPN). Seemingly unaware that more than fifty years earlier Benjamin Peirce had proved that an odd perfect number must have at least four distinct prime divisors, Sylvester began his fundamental assault on the problem by establishing the same result. Later that same year, he strengthened his conclusion to five. These findings would help to mark the beginning of the modern era of research on odd perfect numbers. Sylvester's bound stood …
Maximum Likelihood Estimation Of Ordered Multinomial Parameters , Nicholas P. Jewell, Jack Kalbfleisch
Maximum Likelihood Estimation Of Ordered Multinomial Parameters , Nicholas P. Jewell, Jack Kalbfleisch
The University of Michigan Department of Biostatistics Working Paper Series
The pool-adjacent violator-algorithm (Ayer et al., 1955) has long been known to give the maximum likelihood estimator of a series of ordered binomial parameters, based on an independent observation from each distribution (see, Barlow et al., 1972). This result has immediate application to estimation of a survival distribution based on current survival status at a set of monitoring times. This paper considers an extended problem of maximum likelihood estimation of a series of ‘ordered’ multinomial parameters pi = (p1i, p2i, . . . , pmi) for 1 < = I < = k, where ordered means that pj1 < = pj2 < = .. . < = pjk for each j with 1 < = j < = m-1. The data consist of k independent observations X1, . . . ,Xk where Xi has a multinomial distribution with probability parameter pi and known index ni > = 1. By making use of variants of the pool adjacent violator algorithm, …
On Textured Image Analysis Using Wavelets., Mausumi Acharyya Dr.
On Textured Image Analysis Using Wavelets., Mausumi Acharyya Dr.
Doctoral Theses
In image processing and computer vision research, we aim to derive better tools that give us different perspectives on the same image, allowing us to understand not only its content, but also its meaning and significance. Image processing can not compete with the human eye in terms of accuracy but it can outperform the latter easily on observational consistency, and ability to carry out detailed mathematical estimations. With time, image processing research has broadened from the basic pixel-based low- level operations to high-level analysis, that now includes the use of artificially intelligent techniques for image interpretation and understanding. These new …
Coastal Observatory Investigates Energetic Current Oscillations On Southeast Florida Shelf, Alexander Soloviev, Rebekah J. Walker, Robert H. Weisberg, Mark E. Luther
Coastal Observatory Investigates Energetic Current Oscillations On Southeast Florida Shelf, Alexander Soloviev, Rebekah J. Walker, Robert H. Weisberg, Mark E. Luther
Marine & Environmental Sciences Faculty Articles
Coastal circulation along the southeast Florida shelf is strongly related to the dynamics of the Florida Current. The current follows the steep bottom terrain along the shelf break separating the deep ocean from the coastal zone (Figure 1 a, b). Energetic and complex flow regimes arise along the current's western edge, causing transient features such as sub-meso-scale eddies [Lee and Mayer, 1977; Shay et al., 2000] and energetic internal oscillations [Mooers, 1975; Soloviev et al., 2003], which affect mixing between the shelf and deeper ocean waters. Understanding of these regimes is important for modeling and prediction of the …
Using Fecal Glucocorticoids For Stress Assessment In Mourning Doves, Brian E. Washburn, Joshua J. Millspaugh, John H. Schulz, Susan B. Jones, Tony Mong
Using Fecal Glucocorticoids For Stress Assessment In Mourning Doves, Brian E. Washburn, Joshua J. Millspaugh, John H. Schulz, Susan B. Jones, Tony Mong
United States Department of Agriculture Wildlife Services: Staff Publications
Fecal glucocorticoid assays provide a potentially useful, noninvasive means to study physiological responses of wildlife to various stressors. The objective of our study was to validate a method for measuring glucocorticoid metabolites in Mourning Dove (Zenaida macroura) feces. We validated the assay using standard procedures (e.g., parallelism, recovery of exogenous corticosterone) to demonstrate that the assay accurately and precisely measured glucocorticoid metabolites in Mourning Dove fecal extracts. We conducted adrenocorticotropin (ACTH) challenge experiments to validate the assay’s ability to determine biologically important changes in fecal glucocorticoids. Fecal glucocorticoid levels increased significantly approximately 2–3 hr after administration of ACTH …
Effects Of Radio-Transmitters On Fecal Glucocorticoid Levels In Captive Dickcissels, Kimberly M. Suedkamp Wells, Brian E. Washburn, Joshua J. Millspaugh, Mark R. Ryan, Michael W. Hubbard
Effects Of Radio-Transmitters On Fecal Glucocorticoid Levels In Captive Dickcissels, Kimberly M. Suedkamp Wells, Brian E. Washburn, Joshua J. Millspaugh, Mark R. Ryan, Michael W. Hubbard
United States Department of Agriculture Wildlife Services: Staff Publications
We determined the effects of a leg-harness transmitter on fecal glucocorticoid levels of wild male Dickcissels (Spiza americana) in captivity. During the post-breeding season of 2001, we captured 10 male Dickcissels in central Missouri and housed them in individual pens of an outdoor aviary. We radio-tagged five birds; the other five were captured and handled, but were not radio-tagged. We collected fecal samples every other day prior to attachment (31 July– 21 August) and after attachment (24 August–20 September). Body condition and morphology were similar between control and transmitter-equipped birds. We observed a significant interaction between transmitter attachment …
Nonparametric Estimation Of The Bivariate Recurrence Time Distribution, Chiung-Yu Huang, Mei-Cheng Wang
Nonparametric Estimation Of The Bivariate Recurrence Time Distribution, Chiung-Yu Huang, Mei-Cheng Wang
Johns Hopkins University, Dept. of Biostatistics Working Papers
This paper considers statistical models in which two different types of events, such as the diagnosis of a disease and the remission of the disease, occur alternately over time and are observed subject to right censoring. We propose nonparametric estimators for the joint distribution of bivariate recurrence times and the marginal distribution of the first recurrence time. In general, the marginal distribution of the second recurrence time cannot be estimated due to an identifiability problem, but a conditional distribution of the second recurrence time can be estimated non-parametrically. In literature, statistical methods have been developed to estimate the joint distribution …
Clustering Of Galaxies At Z ∼ 3 Around The Probable Damped Lyα Absorber Toward Qso Apm 08279+5255, Nicolas Bouché, James D. Lowenthal
Clustering Of Galaxies At Z ∼ 3 Around The Probable Damped Lyα Absorber Toward Qso Apm 08279+5255, Nicolas Bouché, James D. Lowenthal
Astronomy: Faculty Publications
We present results on the clustering of Lyman break galaxies (LBGs) around a probable damped Lyα absorption line cloud (DLA) at z = 2.974 from deep UBVI images of the field containing the quasar APM 08279+5255 (z = 3.91). The large area covered by our images, 0.31 deg or ∼40 × 40 Mpc comoving at redshift z = 3, and their depth, μ (sky) ≃ 27.6 mag arcsec , allow us to identify ∼450 LBG candidates brighter than I = 24.80 at 2. 75 < z < 3.25 both close (50 kpc) to the DLA line of sight and up to 20 Mpc (comoving) from the DLA, i.e., physically unrelated. LBG candidates were identified using photometric redshift techniques that include the I magnitude as a prior estimate in addition to the colors. The two are combined using Bayes's theorem. This helps to break the degeneracies that occur in a pure spectral template fitting scheme. The overall rms is σ ≃ 0.15 at z ∼ 3 based on our analysis of photometric redshifts in the HDF-N. From the redshift likelihood distributions, we selected LBG galaxies within a redshift slice of width W = 0.15(≃ σ ) centered on the redshift of the DLA z . Within that redshift slice, we find an enhancement of galaxies near the DLA using both the surface density (Σ/Σ ≃ 3) and an estimator of the three-dimensional spatial overdensity (n/n̄ ∼ 5 ± 3). The surface overdensity Σ/Σ is significant at the more than 95% significance level on scales 2.5 < r < 5 Mpc comoving. The overdensity cannot be related to the QSO environment since the QSO is at z = 3.91. These results imply that some DLA could reside in high-density regions. We search within 45″ from the line of sight for galaxies responsible for the DLA and find one candidate with Z = 3.03 that is 26″ (145 kpc physical) away. From its magnitude I = 24.65 ± 0.2, its luminosity is M = -21.35. Due to its large impact parameter, however, this galaxy is not a likely candidate for the absorber. abs em I,AB AB z z z abs g g g θ em phot I,AB 2 -2
Performance Measurement Of Watermark Embedding Patterns, R. Scealy, R. Safavi-Naini, N. P. Sheppard
Performance Measurement Of Watermark Embedding Patterns, R. Scealy, R. Safavi-Naini, N. P. Sheppard
Faculty of Informatics - Papers (Archive)
Segmented watermarking is an approach to multiple watermarking that can be used to acknowledge the contribution of multiple authors or to embed a fingerprint code-word, but is susceptible to cropping attacks that discard portions of the watermarked media. Careful selection of the watermark embedding pattern can increase the resilence of a segmented watermark in the presence of cropping attacks. In this paper, we consider performance measures for embedding patterns and compare the performance of several proposed embedding patterns using these measures.