Sökning: "present perfect"

Visar resultat 21 - 25 av 115 avhandlingar innehållade orden present perfect.

  1. 21. Millimeter-Waves Slot Array Antennas based on Gap Waveguide Technology

    Författare :Jinlin Liu; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Recently, gap waveguide technology is introduced as a promising guiding structure for millimeter-wave systems. The conception of gap waveguide technology can be modeled for theoretical analysis by two parallel plates, a top perfect electric conductor layer and a bottom perfect magnetic conductor layer. LÄS MER

  3. 22. Tense and aspect in Chichewa, Citumbuka and Cisena : A description and comparison of the tense-aspect systems in three southeastern Bantu languages

    Författare :Andrea Kiso; Östen Dahl; Eva Lindström; Bernd Heine; Stockholms universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; Tense; aspect; Chichewa; Citumbuka; Cisena; Bantu; Linguistics; lingvistik;

    Sammanfattning : This dissertation describes and compares the tense-aspect systems found in three southeastern Bantu languages, viz. Chichewa, Citumbuka and Cisena. LÄS MER

  4. 23. Theory of transformation optics and invisibility cloak design

    Författare :Pu Zhang; Sailing He; Hao Yang; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transformation optics; Maxwell’s equations; invisibility cloak; half-space cloak; reduced cloak; inverse transformation; carpet cloak; Electrical engineering; Elektroteknik;

    Sammanfattning : Research on metamaterials has been growing ever since the first experimental realization of double negative media. The theory of transformation optics provides people with a perfect tool to make use of vast possibilities of the constitutive parameters for metamaterials. LÄS MER

  5. 24. Ergonomics: An uncharted route to improved overall systems performance in shipping

    Författare :Cecilia Österman; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; Ergonomics; human factors; quality; safety.; productivity; shipping; efficiency;

    Sammanfattning : Continuously, improved design of hull, propulsion and cargo handling systems has increased speed, capacity and reliability of sea transports. Simultaneously, efforts have been made to perfect crew size and composition in order to optimize operations costs. LÄS MER

  7. 25. Transport phenomena in quantum wells and wires in presence of disorder and interactions

    Författare :Valeria Vettchinkina; Matematisk fysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; time-dependent density-functional theory; disorder; electron correlation; Lowdimensional semiconducting systems; transport phenomena; Fysicumarkivet F:2012:Vettchinkina;

    Sammanfattning : Present-day electronics employ circuits of smaller and smaller dimensions, and today the length scales are so small that the laws of physics which rule micro-cosmos, quantum mechanics, become directly important. This thesis reports on theoretical work on electron transport in different nanostructures. LÄS MER