Maximum crosstalk estimation and modeling of electromagnetic radiation from PCB/high-density connector interfaces

This dissertation explores two topics pertinent to electromagnetic compatibility research: maximum crosstalk estimation in weakly coupled transmission lines and modeling of electromagnetic radiation resulting from printed circuit board/high-density connector interfaces. Despite an ample supply of literature devoted to the study of crosstalk, little research has been performed to formulate maximum crosstalk estimates when signal lines are electrically long. Paper one illustrates a new maximum crosstalk estimate that is based on a mathematically rigorous, integral formulation, where the transmission lines can be lossy and in an inhomogeneous media. Paper two provides a thorough comparison and analysis of the newly derived maximum crosstalk estimates with an estimate derived by another author. In paper two the newly derived estimates in paper one are shown to be more robust because they can estimate the maximum crosstalk with fewer and less restrictive assumptions. One current industry challenge is the lack of robust printed circuit board connector models and methods to quantify radiation from these connectors. To address this challenge, a method is presented in paper three to quantify electromagnetic radiation using network parameters and power conservation, assuming the only losses at a printed circuit board/connector interface are due to radiation. Some of the radiating structures are identified and the radiation physics explored for the studied connector in paper three. Paper four expands upon the radiation modeling concepts in paper three by extending radiation characterization when material losses and multiple signals may be present at the printed circuit board/connector interface. The resulting radiated power characterization method enables robust deterministic and statistical analyses of the radiated power from printed circuit board connectors. Paper five shows the development of a statistical radiated power estimate based on the radiation characterization method presented in paper four. Maximum radiated power estimates are shown using the Markov and Chebyshev inequalities to predict a radiated power limit. A few maximum radiated power limits are proposed that depend on the amount of known information about the radiation characteristics of a printed circuit board connector --Abstract, page iv

Evolution of genes and genomes on the Drosophila phylogeny

Affiliations des auteurs : cf page 216 de l'articleInternational audienceComparative analysis of multiple genomes in a phylogenetic framework dramatically improves the precision and sensitivity of evolutionary inference, producing more robust results than single-genome analyses can provide. The genomes of 12 Drosophila species, ten of which are presented here for the first time (sechellia, simulans, yakuba, erecta, ananassae, persimilis, willistoni, mojavensis, virilis and grimshawi), illustrate how rates and patterns of sequence divergence across taxa can illuminate evolutionary processes on a genomic scale. These genome sequences augment the formidable genetic tools that have made Drosophila melanogaster a pre-eminent model for animal genetics, and will further catalyse fundamental research on mechanisms of development, cell biology, genetics, disease, neurobiology, behaviour, physiology and evolution. Despite remarkable similarities among these Drosophila species, we identified many putatively non-neutral changes in protein-coding genes, non-coding RNA genes, and cis-regulatory regions. These may prove to underlie differences in the ecology and behaviour of these diverse species

Evolution of genes and genomes on the Drosophila phylogeny

Comparative analysis of multiple genomes in a phylogenetic framework dramatically improves the precision and sensitivity of evolutionary inference, producing more robust results than single-genome analyses can provide. The genomes of 12 Drosophila species, ten of which are presented here for the first time (sechellia, simulans, yakuba, erecta, ananassae, persimilis, willistoni, mojavensis, virilis and grimshawi), illustrate how rates and patterns of sequence divergence across taxa can illuminate evolutionary processes on a genomic scale. These genome sequences augment the formidable genetic tools that have made Drosophila melanogaster a pre-eminent model for animal genetics, and will further catalyse fundamental research on mechanisms of development, cell biology, genetics, disease, neurobiology, behaviour, physiology and evolution. Despite remarkable similarities among these Drosophila species, we identified many putatively non-neutral changes in protein-coding genes, non-coding RNA genes, and cis-regulatory regions. These may prove to underlie differences in the ecology and behaviour of these diverse species