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Visar resultat 1 - 5 av 101 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Students' understandings of multiplication

   Författare :Kerstin Larsson; Kerstin Pettersson; Paul Andrews; Lieven Verschaffel; Stockholms universitet; []
   Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Multiplication; students’ understanding; connections; multiplicative reasoning; models for multiplication; calculations; arithmetical properties; matematikämnets didaktik; Mathematics Education;

   Sammanfattning : Multiplicative reasoning permeates many mathematical topics, for example fractions and functions. Hence there is consensus on the importance of acquiring multiplicative reasoning. LÄS MER

3. 2. Low Power and Low complexity Constant Multiplication using Serial Arithmetic

   Författare :Kenny Johansson; Lars Wanhammar; Oscar Gustafsson; Süleyman Demirsoy; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; FIR filters; Computer arithmetic; Multiplication; Addition; Low power; Switching activity; Electronics; Elektronik;

   Sammanfattning : The main issue in this thesis is to minimize the energy consumption per operation for the arithmetic parts of DSP circuits, such as digital filters. More specific, the focus is on single- and multiple-constant multiplication using serial arithmetic. The possibility to reduce the complexity and energy consumption is investigated. LÄS MER

4. 3. Low Power and Low Complexity Shift-and-Add Based Computations

   Författare :Kenny Johansson; Oscar Gustafsson; Lars Wanhammar; Izzet Kale; Linköpings universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; FIR filters; Function approximation; Digital circuits; Computer arithmetic; Constant multiplication; Addition; Low power; Switching activity estimation; Electronics; Elektronik;

   Sammanfattning : The main issue in this thesis is to minimize the energy consumption per operation for the arithmetic parts of DSP circuits, such as digital filters. More specific, the focus is on single- and multiple-constant multiplications, which are realized using shift-and-add based computations. The possibilities to reduce the complexity, i.e. LÄS MER

5. 4. Spatiotemporal carrier dynamics in graphene

   Författare :Roland Jago; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; spatiotemporal dynamics; density matrix formalism; graphene; relaxation dynamics; carrier multiplication; Bloch equations; photoconduction effect; bolometric effect;

   Sammanfattning : Graphene as an atomically thin material exhibits remarkable optical and electronic properties that suggest its technological application in novel optoelectronic devices, such as graphene-based photodetectors and lasers. To understand the properties of such devices on a microscopic level, we study the interplay of optical excitation, carrier-carrier, carrier-phonon, and carrierphoton scattering as well as diffusion processes. LÄS MER

7. 5. Electron dynamics in graphene in the presence of an electrical field

   Författare :Roland Jago; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bloch equations; density matrix formalism; graphene; relaxation dynamics; photoconduction effect; carrier multiplication;

   Sammanfattning : Graphene as atomically thin two-dimensional material exhibits remarkableoptical and electronic properties that suggest its technological applicationin novel optoelectronic devices, such as graphene-based lasers and photodetectors.The linear electronic bandstructure and the vanishing band gap atthe Dirac point open up new relaxation channels, such as Auger scattering. LÄS MER