• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 864
  • 412
  • 156
  • 84
  • 79
  • 35
  • 27
  • 16
  • 16
  • 14
  • 13
  • 10
  • 9
  • 8
  • 8
  • Tagged with
  • 2082
  • 2082
  • 547
  • 431
  • 430
  • 382
  • 380
  • 202
  • 190
  • 165
  • 162
  • 157
  • 150
  • 147
  • 146
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Data-based statistical methods

Young, G. A. January 1986 (has links)
No description available.
2

Time series analysis of compositional data

Brunsdon, T. M. January 1987 (has links)
No description available.
3

Bayesian Data Analysis For The Sovenian Plebiscite

Padhy, Budhinath 28 April 2011 (has links)
Slovenia became an independent republic with its own constitution passed on December 23, 1991. The important step that led to the independence of Slovenia was the December 1990 plebiscite. It was at this plebiscite that the citizens of Slovenia voted for a sovereign and independent state. A public survey called Slovenian Public Opinion (SPO) survey was taken by the government of Slovenia for the plebiscite. The plebiscite counted `YES voters' only those voters who attended and who voted for independence. Non-voters were counted as `NO voters' and `Don't Know' survey responses that could be thought of as missing data that was treated as `YES' or `NO'. Analysis of survey data is done using non-parametric fitting procedure, Bayesian ignorable nonresponse model and Bayesian nonignorable nonresponse model. Finally, a sensitivity analysis is conducted with respect to the different values of a prior parameter. The amazing estimates of the eventual plebiscite outcome show the validity our underlying models.
4

Analýza intranetu společnosti Sprinx Systems, a.s. a návrhy na jeho zlepšení. / Analysis of the intranet Sprinx Systems, a.s. and suggestions for its improvement

Perná, Lucie January 2011 (has links)
This diploma thesis devote to design a search of intranets questions and analysis of the current state of the corporate intranet Sprinx Systems, a.s. Intranet can be as useful for small and big company. A well-functioning intranet secures the know-how of company and helps its users at work. The first part of this diploma thesis is focused on design a search of intranet questions, which contains for example historical development of intranets, the basic functions of intranets, create intranet plan, planning intranet content etc. The second part of diploma thesis is focused on the analysis of the current intranet, which was performed using our own experience, structured interview with managers and a questionnaire survey, evaluation and recommendation of proposals to improve the company`s intranet for the future.
5

Estimating the parameters of the truncated normal distribution

Akhter, A. S. January 1987 (has links)
No description available.
6

Analysis and application of polarisation diversity radar data

McGuinness, R. January 1984 (has links)
No description available.
7

High Precision Cosmology with CMB Data

Farhang, Marzieh 07 August 2013 (has links)
In this thesis we investigate the two cosmic epochs of inflation and recombination, through their imprints on the temperature and polarization anisotropies of the cosmic microwave background radiation. To probe the early universe we develop a map-based maximum-likelihood estimator to measure the amplitude of inflation-induced gravity waves, parametrized by $r$, from the cosmic microwave background (CMB) polarization maps. Being optimal by construction, the estimator avoids $E$-$B$ mixing, a possible source of contamination in the tiny $B$-mode detection, the target of many current and near future CMB experiments. For various observational cases, we probe the dependence of $r$ measurement on the signal from different scales of $E$ and $B$ polarization. We make forecasts for Spider-like and Planck-like experimental specifications and to investigate the sky-coverage optimization of the Spider-like case. We also use a novel information-based framework to compare how different generations of CMB experiments reveal information about the early universe, through their measurements of $r$. We also probe the epoch of recombination by investigating possible fluctuations in the free electron fraction $\Xe$ around the fiducial model of the standard recombination scenario. Though theoretically well studied, the detailed assumptions in the recombination history, based on standard atomic physics, have never been directly tested. However, for our CMB-based cosmological inferences to be reliable, the recombination scenario needs to be observationally verified. We approach this problem in a model-independent way and construct rank-ordered parameter eigen-modes with the highest power to probe $\Xe$. We develop an information-based criterion to truncate the eigen-mode hierarchy, which can be used in similar hierarchical model selections as well. The method is applied to simulations of Planck+ACTPol and a cosmic variance limited survey with differing simulated recombination histories and recovered $\Xe$ trajectories are constructed. We apply the method to currently available CMB datasets, WMAP9+ACT/SPT. The first constructed eigen-mode turns out to be a direct measure of the damping envelope. Its current measurement with SPT slightly indicates a damping tail anomaly, while ACT data agree well with the standard scenario. High resolution Planck data will resolve this tension with high significance.
8

High Precision Cosmology with CMB Data

Farhang, Marzieh 07 August 2013 (has links)
In this thesis we investigate the two cosmic epochs of inflation and recombination, through their imprints on the temperature and polarization anisotropies of the cosmic microwave background radiation. To probe the early universe we develop a map-based maximum-likelihood estimator to measure the amplitude of inflation-induced gravity waves, parametrized by $r$, from the cosmic microwave background (CMB) polarization maps. Being optimal by construction, the estimator avoids $E$-$B$ mixing, a possible source of contamination in the tiny $B$-mode detection, the target of many current and near future CMB experiments. For various observational cases, we probe the dependence of $r$ measurement on the signal from different scales of $E$ and $B$ polarization. We make forecasts for Spider-like and Planck-like experimental specifications and to investigate the sky-coverage optimization of the Spider-like case. We also use a novel information-based framework to compare how different generations of CMB experiments reveal information about the early universe, through their measurements of $r$. We also probe the epoch of recombination by investigating possible fluctuations in the free electron fraction $\Xe$ around the fiducial model of the standard recombination scenario. Though theoretically well studied, the detailed assumptions in the recombination history, based on standard atomic physics, have never been directly tested. However, for our CMB-based cosmological inferences to be reliable, the recombination scenario needs to be observationally verified. We approach this problem in a model-independent way and construct rank-ordered parameter eigen-modes with the highest power to probe $\Xe$. We develop an information-based criterion to truncate the eigen-mode hierarchy, which can be used in similar hierarchical model selections as well. The method is applied to simulations of Planck+ACTPol and a cosmic variance limited survey with differing simulated recombination histories and recovered $\Xe$ trajectories are constructed. We apply the method to currently available CMB datasets, WMAP9+ACT/SPT. The first constructed eigen-mode turns out to be a direct measure of the damping envelope. Its current measurement with SPT slightly indicates a damping tail anomaly, while ACT data agree well with the standard scenario. High resolution Planck data will resolve this tension with high significance.
9

Statistical analysis of multivariate interval-censored failure time data

Chen, Man-Hua, January 2007 (has links)
Thesis (Ph.D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 6, 2009) Includes bibliographical references.
10

Fundamental parameters of the Milky Way galaxy

Camarillo, Tia January 1900 (has links)
Master of Science / Department of Physics / Bharat Ratra / Over three-quarters of observed galaxies are spiral galaxies, and of those spirals roughly two-thirds are barred. The Milky Way, a barred spiral galaxy, is naturally a great foundation to studying the structure of other barred spiral galaxies. Two important fundamental constants are used to describe the Milky Way, R₀ (the radial distance from the Sun to the Galactic center) and θ₀ (the Galactic rotational velocity at R₀). These two constants are also crucial for developing the rotation curve of the Galaxy, which helps to understand the mass distribution of the Galaxy and may be able to lend insight to the dark matter mass contribution. This work presents new, independently calculated values for R₀ and θ₀. The error distributions of a compilation of 28 (since 2011) independent measurements of R₀ are wider than a standard Gaussian and best fit by an n=4 Student's t probability density function. Given this non-Gaussianity, the results of our median statistics analysis, summarized as R₀ = 8.0 ± 0.3 kpc (2σ error), probably provides the most reliable estimate of R₀. The unsymmetrized value for R₀ is R₀ = 7.96+0.24-0.30 kpc (2σ error). A complete collection of 18 recent (since 2000) measurements of θ0 indicates a median statistics estimate of θ₀ = 220 ± 10 km/s ⁻¹ (2σ error) as the most reliable summary for most practical purposes, at R0 = 8.0 ± 0.3 kpc (2σ error). The resulting error distribution of this data set is only mildly non-Gaussian, much more so than that of R₀. These measurements use tracers that are believed to more accurately reflect the systematic rotation of the Milky Way. Unlike other recent compilations of R₀ and θ₀, our collections includes only independent measurements. This work concludes with a new set of Galactic constants (with 1σ error bars) of θ₀ = 222 ± 6 km s⁻¹, R₀ = 7.96 ± 0.17 kpc, and ω₀ = θ₀/ R₀ = 27.9 ± 1.0 km s⁻¹ kpc⁻¹ as probably the most reliable to date.

Page generated in 0.0737 seconds