Search for dissertations about: "non linearity"

Showing result 1 - 5 of 100 swedish dissertations containing the words non linearity.

2. 1. Acoustic source characterisation for non-linear in-duct sources

   Author : Fredrik Albertson; KTH; []
   Keywords : in-duct source; source characterisation; non-linear source; linearity test; hybrid method; IC-engine; muffler; coupling method;

   Abstract : Different ways to model acoustic in-duct sources have beenanalysed. Measurements were conducted on two diesel truckengines. It was found that for steady state oscillations, onecould linearise in the neighbourhood of a given linearisationpoint, i.e. READ MORE

4. 2. Improvement and Assessment of Two-Dimensional Resistivity Models Derived from Radiomagnetotelluric and Direct-Current Resistivity Data

   Author : Thomas Kalscheuer; Laust B. Pedersen; Christopher Juhlin; Roland Roberts; Heinrich Brasse; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Electromagnetic geophysics; radiomagnetotellurics; direct-current resistivity; displacement currents; dielectric effect; non-linearity; inversion; regularization; two-dimensional model; model variance; model resolution; data resolution; Geophysics; Geofysik;

   Abstract : Two-dimensional (2-D) models of electrical resistivity are improved by jointly inverting radiomagnetotelluric (RMT) and direct-current resistivity (DCR) data or by allowing for displacement currents in the inversion of RMT data collected on highly resistive bedrock. Uniqueness and stability of the 2-D models are assessed with a model variance and resolution analysis that allows for the non-linearity of the inverse problem. READ MORE

5. 3. Active Vibration Control of Multibody Systems : Application to Automotive Design

   Author : Claes Olsson; Alexander Medvedev; Stephen Elliott; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Active Vibration Control; Vibration Isolation; Feedback Control; Adaptive Filtering; Saturation; Limit Cycles; Multi Body Systems; Modelling; Simulation; Non-linearity; Gain Scheduling; Structure Flexibility; Automatic control; Reglerteknik;

   Abstract : Active vibration control to reduce vibrations and structure borne noise is considered using a powerful multi-disciplinary virtual design environment which enables control system design to be considered as an integral part of the overall vehicle design. The main application studied is active automotive engine vibration isolation where, first, the potential of large frequency band multi-input multi-output H2 feedback control is considered. READ MORE

6. 4. Laser-Induced Phosphor Thermometry - Feasibility and Precision in Combustion Applications

   Author : Johannes Lindén; Förbränningsfysik; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Laser-Induced Phosphorescence; Laser Combustion Diagnostics; Non-linearity; Image Intensifier; Two-color Ratio; Lifetime Decay; Precision; Thermographic Phosphors; Temperature measurements; Fysicumarkivet A:2012:Lindén;

   Abstract : Temperature is one of the most fundamental parameters to be measured in many research disciplines. In combustion science, a thorough knowledge of temperature is essential for improving and optimizing combustion processes. READ MORE

7. 5. Characterization and Compensation of Hardware Impairments in Transmitters for Wireless Communications

   Author : Zain Ahmed Khan; Peter Händel; Magnus Isaksson; Mikko Valkama; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power amplifier; RF transmitters; SISO; MIMO; crosstalk; Volterra series; Volterra kernels; behavioral modeling; DPD; Ramanujan sums; multitone signals; I Q Imbalance; non-linearity; memory polynomial; density estimation; hardware impairments; Electrical Engineering; Elektro- och systemteknik;

   Abstract : Increasing demands for data rate, energy efficiency and reliability in wireless communications have resulted in the introduction of radio frequency (RF) multiple input multiple output (MIMO) transmitters. However, MIMO transmitters suffer from additional crosstalk impairments along with the power amplifier (PA) and I/Q imbalance distortions observed in single input single output (SISO) transmitters. READ MORE