Sökning: "Linear arrays"

Visar resultat 1 - 5 av 63 avhandlingar innehållade orden Linear arrays.

1. 1. Multidimensional Piecewise Regular Arrays

   Författare :Toomas P. Plaks; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polytopes; commutativity; systolic arrays; associativity; space-time mapping; piecewise regular arrays;

   Sammanfattning : Regular arrays, particularly systolic arrays, have been the subject of continuous interest for the past 15 years. One reason is that they present an excellent example of the unity between hardware and software, especially for application-specific computations. LÄS MER

3. 2. Numerical and experimental modelling for wave energy arrays optimization

   Författare :Marianna Giassi; Malin Göteman; Jan Isberg; Gregorio Iglesias; Uppsala universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wave energy; Point absorber; Arrays; Parks; Farms; Optimization; Array layout; Genetic algorithm; Cost function; Wave tank experiment; Hydrodynamics; Economical model; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Sammanfattning : Many wave power conversion devices, especially point-absorbers, do not provide alone the necessary amount of converted electricity to be cost effective, instead they are designed to be deployed in arrays of many units. Such arrays, or parks, can satisfy a large-scale energy demand, reduce the costs of the produced electricity and improve the reliability of the system. LÄS MER

4. 3. Single and Accumulative Electron Transfer – Prerequisites for Artificial Photosynthesis

   Författare :Susanne Karlsson; Leif Hammarström; Hans-Christian Becker; Devens Gust; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Artificial photosynthesis; Photoinduced charge separation; Electron transfer; Energy transfer; Accumulative electon transfer; Donor-acceptor; Ruthenium; Linear arrays; Chemical physics; Kemisk fysik; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

   Sammanfattning : Photoinduced electron transfer is involved in a number of photochemical and photobiological processes. One example of this is photosynthesis, where the absorption of sunlight leads to the formation of charge-separated states by electron transfer. LÄS MER

5. 4. Characterisation and modelling of graphene FET detectors for flexible terahertz electronics

   Författare :Xinxin Yang; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sensors; arrays; scattering parameters; broadband characterisation; graphene; terahertz detectors; field-effect transistors; flexible electronics;

   Sammanfattning : Low-cost electronics for future high-speed wireless communication and non-invasive inspection at terahertz frequencies require new materials with advanced mechanical and electronic properties. Graphene, with its unique combination of flexibility and high carrier velocity, can provide new opportunities for terahertz electronics. LÄS MER

7. 5. On MIMO Systems and Adaptive Arrays for Wireless Communication : Analysis and Practical Aspects

   Författare :Mattias Wennström; Michael A. Jensen; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Systemteknik; antenna array; calibration; MIMO system; flat fading; non-linear amplifier; switched parasitic antenna; analog beamformer; adaptive antenna testbed; Systemteknik; Systems engineering; Systemteknik; Signal Processing; signalbehandling;

   Sammanfattning : This thesis is concerned with the use of multiple antenna elements in wireless communication over frequency non-selective radio channels. Both measurement results and theoretical analysis are presented. New transmit strategies are derived and compared to existing transmit strategies, such as beamforming and space-time block coding (STBC). LÄS MER