Sökning: "density taper"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden density taper.

  1. 1. Aperiodic Array Synthesis for Telecommunications

    Författare :Carlo Bencivenni; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; PtP; mutual coupling; SATCOM; compressive sensing; aperiodic array; density taper; MU-MIMO; maximally sparse array; LoS-MIMO;

    Sammanfattning : Arrays of antennas offer important advantages over single-element antennas and are thus a key part of most advanced communication systems. The majority of current arrays are based on a classical regular layout, which offer simple design criteria despite some limitations. LÄS MER

  3. 2. Taper and volume equations for poplar trees growing on farmland in Sweden

    Författare :Birger Hjelm; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Effective management of poplar plantations for high yield production would be facilitated by the availability of improved equations for predicting the taper and volume of poplar stems. Therefore, this thesis is based upon a polynomial stem taper equation and two volume equations constructed for individual poplar trees growing on farmland. LÄS MER

  4. 3. Functional properties of silicon nitride based materials for joint applications

    Författare :Luimar N. Corrêa Filho; Cecilia Persson; Julia Shelton; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Silicon nitride; Coatings; Wear; Joint replacements; HiPIMS; Teknisk fysik med inriktning mot materialvetenskap; Engineering Science with specialization in Materials Science;

    Sammanfattning : Total hip and total knee replacements are generally successful procedures for patients suffering with pain due to bone fracture or diseases affecting the joints. However, the materials that are commonly used still have limitations. In particular, corrosion products and wear debris may give rise to negative body reactions. LÄS MER

  5. 4. Fracture and stress in powder compacts

    Författare :Pär Jonsén; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : In the field of powder metallurgy (PM), the production methods are constantly developed and improved to produce components with high precision and strength. Cold uniaxial pressing of powder into a green body is a common process in PM. LÄS MER

  7. 5. Modelling and simulation of powder pressing with consideration of residual stresses

    Författare :Pär Jonsén; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Hållfasthetslära; Solid Mechanics;

    Sammanfattning : In powder metallurgy (PM), production methods are constantly developed and improved to produce component with high precision and strength. Cold uniaxial pressing of powder into a green body is a common process in PM. LÄS MER