Search for dissertations about: "Audible frequency"

Showing result 1 - 5 of 28 swedish dissertations containing the words Audible frequency.

  1. 1. Magneto-sensitive rubber in the audible frequency range

    Author : Peter Blom; Leif Kari; Luigi Bregant; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Magneto-sensitivity; Rubber; Audible frequency range; Amplitude dependence; Vibration isolator; Fletcher-Gent effect; Stiffness; Acoustics; Akustik;

    Abstract : The dynamic behaviour in the audible frequency range of magneto-sensitive (MS) rubber is the focus of this thesis consisting of five papers A-E. Paper A presents results drawn from experiments on samples subjected to different constant shear strains over varying frequencies and magnetic fields. READ MORE

  2. 2. On dynamic properties of rubber isolators

    Author : Mattias Sjöberg; KTH; []
    Keywords : Rubber isolator; Dynamic stiffness; Nonlinear; Payne effect; Audible frequency; Fractional derivative; Mittag-Leffler function; Thermo-rheologically simple; Neo-Hooke;

    Abstract : This work aims at enhancing the understanding and to provideimproved models of the dynamic behavior of rubber vibrationisolators which are widely used in mechanical systems.Initially, a time domainmodel relating compressions tocomponent forces accounting for preload effects, frequency anddynamic amplitude dependence is presented. READ MORE

  3. 3. Reduction of Audible Noise of a Traction Motor at PWM Operation

    Author : Hanna Amlinger; Ines Lopez Arteaga; Siv Leth; Wolfgang Kropp; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; electromagnetic noise; pulse width modulation PWM ; switching frequency; traction motor; Vehicle and Maritime Engineering; Farkostteknik;

    Abstract : A dominating source for the radiated acoustic noise from a train at low speeds is the traction motor. This noise originates from electromagnetic forces acting on the structure resulting in vibrations on the surface and thus radiated noise. It is often perceived as annoying due to its tonal nature. READ MORE

  4. 4. Modelling and Interference Analysis of AC-DC Converters for Immunity to Voltage Disturbances up to 150 kHz

    Author : Selcuk Sakar; Sarah Rönnberg; Math Bollen; Sjef Cobben; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; AC-DC power converters; electromagnetic compatibility EMC ; high frequency disturbances; supraharmonics; switching converters; interharmonics; conducted disturbances; Electric Power Engineering; Elkraftteknik;

    Abstract : The function of electrical and electronic equipment is challenged by the high frequency emission originated from the more use of switching-based power electronic equipment and Power line communication (PLC) signaling. Investigations have shown that interferences occur in the frequency range between 2 kHz and 150 kHz, e.g. READ MORE

  5. 5. Propagation of Supraharmonics in Low-Voltage Networks

    Author : Angela Espin Delgado; Sarah Rönnberg; Math Bollen; Jos Knockaert; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; supraharmonics; waveform distortion; low-voltage; high-frequency harmonics; Electric Power Engineering; Elkraftteknik;

    Abstract : The need for measures towards a sustainable use of energy has incited the proliferation of devices and systems for the efficient use of electricity. Energy-efficient appliances, equipment for the electrification of transportation, electricity generators from renewable energy sources, and communication protocols, e.g. READ MORE