• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 336
  • 39
  • 30
  • 12
  • 10
  • 10
  • 10
  • 10
  • 10
  • 10
  • 6
  • 1
  • 1
  • Tagged with
  • 449
  • 449
  • 122
  • 120
  • 47
  • 47
  • 45
  • 43
  • 42
  • 36
  • 35
  • 34
  • 32
  • 31
  • 30
  • 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.
381

Alleviating ecological bias in generalized linear models and optimal design with subsample data /

Glynn, Adam. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (p. 105-107).
382

Reconstruction from projections based on detection and estimation of objects

January 1983 (has links)
pt.1. Performance analysis--pt.2. Robustness analysis. / David J. Rossi, Alan S. Willsky. / Includes bibliographies. / Caption title. "13 July 1983." / National Science Foundation grant ECS-8012668
383

Combining and updating of local estimates and regional maps along sets of one-dimensional tracks

January 1979 (has links)
Alan S. Willsky ... [et al.]. / Microfiche copy available in Barker Engineering Library. / Also available on microfiche. "AD-A080034." / Bibliography: leaves 56-57. / Interim report. / Air Force Office of Scientific Research Grant AFOSR-77-3281B Office of Naval Research Contract ONR/N00014-76-C-0346 Task 61102F 2304/A1
384

Reconstruction from projections based on detection and estimation of objects

January 1983 (has links)
David J. Rossi, Alan S. Willsky. / Caption title. "Presented at the 1983 International Conference on Acoustics, Speech and Signal Processing." / Bibliography: leaf [3] / National Science Foundation Grant ECS-8012668
385

Dual estimation of the poles and zeros of an ARMA(p,q) process

January 1985 (has links)
M. Isabel Ribeiro, Jose M.F. Moura. / "September 1985." / Bibliography: p. 33-34. / Army Research Office Contract DAAG-29-84-K-0005
386

Fundamental Limits on Performance for Cooperative Radar-Communications Coexistence

January 2018 (has links)
abstract: Spectral congestion is quickly becoming a problem for the telecommunications sector. In order to alleviate spectral congestion and achieve electromagnetic radio frequency (RF) convergence, communications and radar systems are increasingly encouraged to share bandwidth. In direct opposition to the traditional spectrum sharing approach between radar and communications systems of complete isolation (temporal, spectral or spatial), both systems can be jointly co-designed from the ground up to maximize their joint performance for mutual benefit. In order to properly characterize and understand cooperative spectrum sharing between radar and communications systems, the fundamental limits on performance of a cooperative radar-communications system are investigated. To facilitate this investigation, performance metrics are chosen in this dissertation that allow radar and communications to be compared on the same scale. To that effect, information is chosen as the performance metric and an information theoretic radar performance metric compatible with the communications data rate, the radar estimation rate, is developed. The estimation rate measures the amount of information learned by illuminating a target. With the development of the estimation rate, standard multi-user communications performance bounds are extended with joint radar-communications users to produce bounds on the performance of a joint radar-communications system. System performance for variations of the standard spectrum sharing problem defined in this dissertation are investigated, and inner bounds on performance are extended to account for the effect of continuous radar waveform optimization, multiple radar targets, clutter, phase noise, and radar detection. A detailed interpretation of the estimation rate and a brief discussion on how to use these performance bounds to select an optimal operating point and achieve RF convergence are provided. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2018
387

Aspectos matematicos do Filtro de Kalman discreto / Mathematical aspects of the Discrete Kalman's Filter

Gonçalves, Dimas José 21 February 2005 (has links)
Orientador: Raymundo Luiz de Alencar / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matematica, Estatistica e Computação Cientifica / Made available in DSpace on 2018-08-04T11:13:34Z (GMT). No. of bitstreams: 1 Goncalves_DimasJose_M.pdf: 1368395 bytes, checksum: 8fae1804e08750be7d9fe13ae39638d5 (MD5) Previous issue date: 2005 / Resumo: Neste trabalho, agrupamos um mínimo de conteúdo matemático para desenvolver uma prova do Teorema do Filtro de Kalman (discreto). A teoria de integração de Lebesgue e alguns elementos ( Teorema da Projeção) da teoria dos espaços de Hilbert são as principais ferramentas matemáticas incluídas, além de um estudo das principais propriedades da esperança condicional / Abstract: In this work we set a minimum of mathematical background to develop a proof of the (discrete) Kalman Filter Theorem.The lebesgue integration theory and some elements (the projection theorem) of the Hilbert space theory are the main mathematical tools included, besides a study of the main properties of the conditional expectation / Mestrado / Analise Funcional / Mestre em Matemática
388

Maximization of power in randomized clinical trials using the minimization treatment allocation technique

Marange, Chioneso Show January 2010 (has links)
Generally the primary goal of randomized clinical trials (RCT) is to make comparisons among two or more treatments hence clinical investigators require the most appropriate treatment allocation procedure to yield reliable results regardless of whether the ultimate data suggest a clinically important difference between the treatments being studied. Although recommended by many researchers, the utilization of minimization has been seldom reported in randomized trials mainly because of the controversy surrounding the statistical efficiency in detecting treatment effect and its complexity in implementation. Methods: A SAS simulation code was designed for allocating patients into two different treatment groups. Categorical prognostic factors were used together with multi-level response variables and demonstration of how simulation of data can help to determine the power of the minimization technique was carried out using ordinal logistic regression models. Results: Several scenarios were simulated in this study. Within the selected scenarios, increasing the sample size significantly increased the power of detecting the treatment effect. This was contrary to the case when the probability of allocation was decreased. Power did not change when the probability of allocation given that the treatment groups are balanced was increased. The probability of allocation { } k P was seen to be the only one with a significant effect on treatment balance. Conclusion: Maximum power can be achieved with a sample of size 300 although a small sample of size 200 can be adequate to attain at least 80% power. In order to have maximum power, the probability of allocation should be fixed at 0.75 and set to 0.5 if the treatment groups are equally balanced.
389

Informação quântica com estados coerentes comprimidos da luz / Quantum information with squeezed coherent states of the light

Souza, Douglas Delgado de, 1987- 28 August 2018 (has links)
Orientador: Antonio Vidiella Barranco / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-28T00:18:27Z (GMT). No. of bitstreams: 1 Souza_DouglasDelgadode_D.pdf: 6011689 bytes, checksum: b920d0dfb23c23b599d6bf1a254285ec (MD5) Previous issue date: 2015 / Resumo: Na primeira parte deste trabalho seguimos os estudos de Hirota e colaboradores e definimos quatro estados quase-Bell baseados em estados coerentes comprimidos da luz. Dois desses estados são maximamente emaranhados, enquanto o emaranhamento dos outros dois depende apenas da sobreposição entre os estados coerentes comprimidos que os compõem. A partir destes estados quase-Bell, definimos novos estados interpolados cujo emaranhamento é também governado por um parâmetro de interpolação adicional e estudamos algumas das propriedades destes estados (emaranhamento e eficiência energética). Por fim, usamos estes estados e definimos alguns estados de Werner, com os quais analisamos de forma simples uma possível influência de um ambiente dissipativo parametrizado pela probabilidade de o estado de Werner estar em sua forma emaranhada ou misturada. Para esta análise usamos os conceitos de separabilidade e emaranhamento. Na segunda parte estudamos a estimativa de fase quântica usando estados gaussianos puros (estados coerentes comprimidos). Iniciamos com a estimativa da fase introduzida por um operador unitário em cujo hamiltoniano está presente uma perturbação linear nos operadores de criação e aniquilação, além do operador de número de fótons responsável pela evolução de fase (perturbação linear unitária). Obtemos quais são os estados gaussianos ótimos para a estimativa desta fase e analisamos a optimalidade da detecção homódina. A seguir, consideramos o parâmetro de perturbação como uma variável aleatória que obedece a uma distribuição gaussiana de probabilidades (perturbação linear aleatória) e novamente obtemos os estados de sonda ótimos e analisamos a optimalidade da detecção homódina. Por fim, estudamos a estimativa de fase com perturbação linear unitária utilizando os estados quase-Bell interpolados definidos na primeira parte deste trabalho e verificamos que a utilização de emaranhamento permite uma melhor estimativa de fase para uma mesma energia disponível / Abstract: In the first part of this work we follow the studies of Hirota and collaborators and we define four quasi-Bell states based on squeezed coherent states of light. Two of these states are maximally entangled, while the entanglement of the other two depends only on the overlap between the squeezed coherent states that were combined. From these quasi-Bell states we define new interpolated states for which the entanglement is also governed by an additional interpolation parameter, and we study some of the properties of these states (entanglement and energy efficiency). Finally, we use these states to define some Werner states, which we use to study in a simple way the possible influence of some dissipative environment parameterized by the probability that the Werner state is entangled or mixed. For this analysis we use the concepts of separability and entanglement. In the second part, we study the quantum phase estimation using pure Gaussian states (squeezed coherent states). We begin with the estimation of the phase introduced by a unitary operator whose Hamiltonian also contains a disturbance that is linear in the creation and annihilation operators in addition to the photon number operator responsible for the phase evolution (unitary linear disturbance). We find what are the optimal Gaussian states for this phase estimation and we also analyze the optimality of the homodyne detection. Next, we consider the disturbance parameter to be a random variable submitted to a Gaussian distribution (random linear disturbance) and again we find what are the optimal probe states and analyze the optimality of the homodyne detection. Finally we study the phase estimation with unitary linear disturbance using the interpolated quasi-Bell states defined in the first part of this work and we verify that the use of entanglement leads to a better phase estimation for the same amount of available energy / Doutorado / Física / Doutor em Ciências / 2011/00220-5 / FAPESP
390

Spectral estimation for sensor arrays

Lang, Stephen William January 1981 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaves 74-76. / by Stephen W. Lang. / Ph.D.

Page generated in 0.1034 seconds