Sökning: "Inverse theory"

Visar resultat 21 - 25 av 151 avhandlingar innehållade orden Inverse theory.

1. 21. Network models with applications to genomic data: generalization, validation and uncertainty assessment

   Författare :José Sánchez; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Inverse covariance matrix; precision matrix; graphical models; high-dimension; low-sample; networks; sparsity; fused lasso; elastic net; cancer; TCGA pan cancer analysis; online resource; discriminant analysis; classification; networks;

   Sammanfattning : The aim of this thesis is to provide a framework for the estimation and analysis of transcription networks in human cancer. The methods we develop are applied to data collected by The Cancer Genome Atlas (TCGA) and supporting simulations are based on derived models in order to reflect real data structure. LÄS MER

3. 22. Some Aspects of Propensity Score-based Estimators for Causal Inference

   Författare :Ronnie Pingel; Johan Lyhagen; Theis Lange; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; correlation; treatment effect; inverse probability weighting; local linear estimator; matching; multicollinearity; observational study.; Statistics; Statistik;

   Sammanfattning : This thesis consists of four papers that are related to commonly used propensity score-based estimators for average causal effects.The first paper starts with the observation that researchers often have access to data containing lots of covariates that are correlated. LÄS MER

4. 23. Satistical Modelling Of CO2 Exchange Between Land And Atmosphere : Using Stochastic Optimisation And Gaussian Markov Random Fields

   Författare :Unn Dahlén; Spatio-Temporal Stochastic Modelling Group; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gaussiska Markovfält; Stokastisk optimering; CO2-flöden; Spatial statistik; Stochastic Optimisation; Gaussian Markov Random Fields; Atmospheric inverse modelling; Spatial statistics; Computational statistics;

   Sammanfattning : This thesis focuses on the development and application of efficient mathematicaltools for estimating and modelling the exchange of carbon dioxide (CO2) between the Earth and its atmosphere; here referred to as the global CO2 surface flux.There are two main approaches for estimating the CO2 flux: Processed based(bottom-up) modelling and atmospheric inversion (top-down) modelling. LÄS MER

5. 24. Relativistic theory of laser-induced magnetization dynamics

   Författare :Ritwik Mondal; Peter M. Oppeneer; Jan Rusz; Olle Eriksson; Paul-Antoine Hervieux; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Relativistic quantum electrodynamics; magneto-optics; spin-orbit coupling; ultrafast demagnetization; inverse Faraday effect; magnetic inertia; Gilbert damping; Fysik; Physics;

   Sammanfattning : Ultrafast dynamical processes in magnetic systems have become the subject of intense research during the last two decades, initiated by the pioneering discovery of femtosecond laser-induced demagnetization in nickel. In this thesis, we develop theory for fast and ultrafast magnetization dynamics. LÄS MER

7. 25. Titchmarsh-Weyl M-function asymptotics and some results in the inverse spectral theory for vector-valued Sturm-Liouville equations and a certain higher order ordinary differential equation

   Författare :Erik Andersson; Matematik (naturvetenskapliga fakulteten); []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Functions; differential equations; Funktioner; differentialekvationer; Paley-Wiener.; The generalized Fourier transform; A certain higher order ordinary differential equation; Borg-Marchenko theorems; Vector-valued Sturm-Liouville equations; Inverse spectral theory; Titchmarsh-Weyl M-function asymptotics; Asymptotics of solutions; Spectral measure;

   Sammanfattning : This discourse is constituted by two separate reprots, where the first one offers an elementary deduction of the leading order term asymptotics for the Titchmarsh-Weyl M-function corresponding to a vector-valued Sturm-Liouville equation of the form -(PU')'+QU=zu, xin[0,b), with P^{-1},W,Q being hermitean with locally integrable entries; and under some additional conditions on P^{-1} and W. In the special case of P=W=I, we give some further asymptotic results for the same M-function. LÄS MER