Sökning: "directional problem"

Visar resultat 16 - 20 av 43 avhandlingar innehållade orden directional problem.

  1. 16. Fluid Power Systems for Mobile Applications : with a Focus on Energy Efficiency and Dynamic Characteristics

    Författare :Mikael Axin; Petter Krus; Birgitta Lantto; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis studies an innovative working hydraulic system design for mobile applications. The purpose is to improve the energy efficiency and the dynamic characteristics compared to load sensing systems without increasing the complexity or adding additional components.The system analysed in this thesis is referred to as flow control. LÄS MER

  3. 17. Novel Hessian approximations in optimization algorithms

    Författare :Erik Berglund; Mikael Johansson; Pontus Giselsson; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : There are several benefits of taking the Hessian of the objective function into account when designing optimization algorithms. Compared to using strictly gradient-based algorithms, Hessian-based algorithms usually require fewer iterations to converge. LÄS MER

  4. 18. Multiple Antenna Terminals in Realistic Environments - A Composite Channel Modeling Approach

    Författare :Fredrik Harrysson; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Channel model; MIMO; multiple antennas terminal; propagation; user interaction; vehicular channel; diversity; spatial multiplexing; channel measurement;

    Sammanfattning : For evaluation of specific antenna arrangements in wireless communication systems we need physical channel models that take into account also the directional domain of the propagation channel. In this thesis we investigate, validate and propose a practical approach to wireless channel modeling and, particularly, to mobile communication systems. LÄS MER

  5. 19. Modeling of the wet-out process in composites manufacturing

    Författare :Da Wu; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; process modeling; liquid composite molding; fiber preform deformation; free surface flow; porous media theory;

    Sammanfattning : The fiber reinforced polymer composites (FRPCs) are carving out a niche amid the keen market competition to replace the other material counterparts, e.g., metals. Due to the low weight and corrosion resistance, the FRPCs are wildly utilized from aviation to automobile industries; both in the sectors of civilian and defense. LÄS MER

  7. 20. Wave Splitting and Effective Boundary Conditions for Structural Elements

    Författare :Martin Johansson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; approximate boundary condition; Mindlin plate; Timoshenko beam; thin plates; cylindrical coordinates; series approximation; wave splitting; dispersion; fluid-loaded plate; Biot;

    Sammanfattning : The subject of this thesis is twofold. The first part concerns the wave splitting of structural elements. The second part concerns approximate boundary conditions for fluid-loaded thin plates. Wave splitting is a mathematical tool for the formulation of scattering problems in the time domain that aims at solving inverse problems, e. LÄS MER