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Showing result 1 - 5 of 8 swedish dissertations matching the above criteria.

2. 1. Studies of flow duct acoustics with applications to turbocharged engines

   Author : Hans Rämmal; Hans Boden; Mats Åbom; Antonio Torregrosa; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; IC-engine; turbocharger; duct termination; flow duct; exhaust system; inlet system; acoustic source; one-port; two-port; source model; transmission loss; two-port matrix; reflection coefficient; source strength; multi-load method; Acoustics; Akustik;

   Abstract : A number of experimental and theoretical studies, performed in the field of technical flow duct acoustics are presented in this thesis. The acoustical methods treated are implemented on turbocharged IC-engines and engine gas exchange system components. A new method based on the well-known two-load technique has been developed. READ MORE

4. 2. Noise Aspects of some Si-based One Port Devices and Carbon Nanotubes

   Author : Hassan Ouacha; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; etching; Schottky contacts; noise; fluctuations; generation; mobility; noise spectroscopy; recombination; p-n diodes; carbon nanotubes; thermal reaction; junction; defects; co-sputtering; irradiation; interface states; low frequency noise;

   Abstract : The p-n junctions and Schottky diodes based on Si1-xGex and SiC are of great importance in modern electronic applications, such as microwave detectors and mixers. Carbon nanotubes (CNTs) have appeared recently as an attractive new class of materials with a reduced dimensionality, and proposed as building blocks for nanoelectronic technology. READ MORE

5. 3. Integration of Surface Acoustic Wave and Microfluidic Technologies for Liquid-Phase Sensing Applications

   Author : Kiryl Kustanovich; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; IDE; Resonator; SH-SAW; Impedance Spectroscopy; Surface Acoustic Wave; PDMS; LiNbO3; Microfluidics; Sensor;

   Abstract : This thesis discusses a new concept for construction of a novel SAW in-liquid sensor employing surface acoustic wave resonance (SAR) in a one-port configuration. In this concept, the reflective gratings of a one-port SAW resonator are employed as mass loading-sensing elements, while the SAW transducer is protected from the measurement environment, reducing power losses significantly. READ MORE

6. 4. Methods for Modelling and Characterization of In-Duct Sources

   Author : Hans Rämmal; Hans Bodén; Mats Åbom; Antonio Torregrosa; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : Methods to characterize acoustic sources in flow ducts have been investigated. In the first part of this thesis a measurement procedure to characterize an air terminal device using an acoustic one-port source model based on the two microphone technique has been tested and validated. READ MORE

7. 5. Estimation of line properties in the copper access network

   Author : Fredrik Lindqvist; Institutionen för elektro- och informationsteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Abstract : The copper access-network operators face the challenge of developing and maintaining cost-effective digital subscriber line (DSL) services that are competitive to other broadband access technologies. The way forward is dictated by the demand of ever increasing data rates on the twisted-pair copper lines. READ MORE