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Visar resultat 1 - 5 av 81 avhandlingar som matchar ovanstående sökkriterier.

1. 1. AlN Thin Film Electroacoustic Devices

   Författare :Gonzalo Fuentes Iriarte; I.V. Katardjiev; G.F. Iriarte; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; Elektroteknik; elektronik och fotonik; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik; elektronik; Electronics;

   Sammanfattning : Recently, the enormous growth in personal communications systems (PCS), satellite communication and various other forms of wireless data communication has made analogue frequency control a key issue as the operation frequency increases to the low/medium GHz range. Surface acoustic wave (SAW) and bulk acoustic wave (BAW) electroacoustic devices are widely used today in a variety of applications both in consumer electronics as well as in specialized scientific and military equipment where frequency control is required. LÄS MER

3. 2. Acoustic and afterload evaluation of left ventricular assist devices

   Författare :Per Sundbom; Henrik Casimir Ahn; Laila Hübbert; Fredrik Gustafsson; Daniel M. G. Karlsson; Michael Broomé; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Afterload; Electronic stethoscope; Flow; HeartMate II; HeartMate 3; iOS-devices; Sound Analysis;

   Sammanfattning : Background: Heart Failure is a serious condition with consequences not only for the individual patient but also for the society with a 5-year mortality rate of 45-60%, and a substantial economic burden. The estimated prevalence in Sweden is 2.2% and the age adjusted prevalence increases with higher age. LÄS MER

4. 3. Computational analysis and design optimization for acoustic devices

   Författare :Abbas Mousavi; Eddie Wadbro; Martin Berggren; Niels Aage; Umeå universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Design optimization; computational analysis; viscothermal acoustics; material distribution topology optimization; acoustic black holes; finite element method;

   Sammanfattning : This thesis focuses on material distribution topology optimization for acoustic waveguides. The limitations of the material distribution approach are discussed in the context of acoustic waveguides with extensive viscous and thermal boundary losses. LÄS MER

5. 4. Studies of acoustic waves, noise and charge pumping using single-electron devices

   Författare :Martin Gustafsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; single-electron pump; single-electron transistor; surface acoustic wave; single-electron devices; charge pumping; TLF; SINIS turnstile; electrometer; two-level fluctuator; single-photon detector; noise; SAW; SET;

   Sammanfattning : This thesis covers a range of experiments on single-electron devices, electrical circuits that utilize the discreetness of the electron charge. The Single-Electron Transistor (SET) is of special importance among these, being the most sensitive electrometer demonstrated, and sufficiently mature to serve as a building block in sensors and detectors for physical phenomena that can be transformed into charge signals. LÄS MER

7. 5. Studies of the Reactive Sputtering Process and its Application in Electro-Acoustic Devices

   Författare :Daniel Rosén; Sören Berg; Ilia Katardjiev; Claes Nender; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Sputtering; Reactive Sputtering; Electro Acoustic Devices; Materialvetenskap; Materials science; Teknisk materialvetenskap;

   Sammanfattning : Electro-acoustic devices such as surface acoustic wave (SAW) and bulk acoustic wave (BAW) devices have been in commercial use for over 60 years and can be found in applications ranging from specialised scientific and military equipment to consumer products, such as mobile telephones, TV and radio receivers, etc. Today by far the largest market for electro-acoustic devices is the telecommunication industry which annually consumes approximately three billion acoustic wave filters for frequency control alone. LÄS MER