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Visar resultat 1 - 5 av 12 uppsatser som matchar ovanstående sökkriterier.

  1. 1. LoRa Based Moisture Sensing System

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Signaler och system

    Författare :Rasha Badran; [2023]
    Nyckelord :LoRa; moisture sensor; capacitive sensor;

    Sammanfattning : Water is an important parameter for crop growth, and the information about the moisture content in soil at different depths is very useful for farmers to determine the best time to water the soil and to irrigate farmland so as to maximize their yield. This thesis project aims to develop a prototype of a multi-depth moisture sensor probe that is part of a large sensing system used in agriculture. LÄS MER

  3. 2. Study of different methodologies to determine relative dielectric constant of given substrate using fabrication, modelling and measurement strategies

    Uppsats för yrkesexamina på avancerad nivå, Luleå tekniska universitet/Institutionen för system- och rymdteknik

    Författare :Anders Lundberg; [2021]
    Nyckelord :Relative dielectric constant; relative permittivity; PCB substrate material;

    Sammanfattning : In this thesis, different methods for measuring the relative dielectric constant is investigated using simulations and experimental approaches. The first method is known as the S-parameter inversion method. In this method formulae is used to calculate the characteristic impedance of the microstrip line from measured S-parameters. LÄS MER

  4. 3. Measurements of resistivity in transformer insulation liquids

    Uppsats för yrkesexamina på avancerad nivå, Uppsala universitet/Institutionen för elektroteknik

    Författare :Jonathan Hägerbrand; [2020]
    Nyckelord :transformer oil; resistivity; ions; ion drift model; HVDC; contact resistance;

    Sammanfattning : This thesis focuses on measuring techniques and results of resistivity in four commercially available insulating transformer oils: mineral oil, ester oil and two isoparaffin oils. Two measuring techniques, the industrially used diagnostic system for electrical insulation IDA and the Labview implemented Triangular Method, are used for resistivity measurements and the techniques are compared, a correction algorithm to the triangular method is suggested. LÄS MER

  5. 4. Ferroelectricity in nanocrystalline Hf0.5Zr0.5O2 thin films

    Master-uppsats, Lunds universitet/Fasta tillståndets fysik; Lunds universitet/Fysiska institutionen

    Författare :Lun Sang; [2018]
    Nyckelord :ferroelectricity; Hf0.5Zr0.5O2; GIXRD; XRR; Technology and Engineering; Physics and Astronomy;

    Sammanfattning : Hafnium dioxide (HfO_2) based thin films doped with various dopants (Si, Ge, Al, Gd, Sr, Zr) have been found to exhibit ferroelectricity. These dopants were found to stabilize the III orthorhombic phase in the hafnium oxide based thin films. LÄS MER

  7. 5. Design, Fabrication and Validation of High-permittivity Low-loss Microwave Material for Biomedical Sensor

    M1-uppsats, Uppsala universitet/Fasta tillståndets elektronik

    Författare :Jasmin Gasi; [2018]
    Nyckelord :Biomedical; high dielectric constant; low loss dielectric; sensors; sin-tering; open ended coaxial probe; open ended circular waveguide; tita-nium dioxide;

    Sammanfattning : Abstract The purpose of this task is to synthesize a dielectric substrate material through a sintering process, which can be used for non-invasive physiological sensor development. Low loss, high dielectric constant ceramic material is used. LÄS MER