Sökning: "Impact test"

Visar resultat 16 - 20 av 1063 avhandlingar innehållade orden Impact test.

  1. 16. Towards improved motorcycle helmet test methods for head impact protection : Using experimental and numerical methods

    Författare :Shiyang Meng; Svein Kleiven; Peter Halldin; Mazdak Ghajari; KTH; []
    Nyckelord :Head Injuries; Helmet; Injury Prevention; Motorcycle; Test Standard; Finite Element Method; Applied Medical Technology; Tillämpad medicinsk teknik;

    Sammanfattning : Head injury is the leading cause of death and major trauma for users of powered two-wheelers (PTWs). Helmet use can prevent and reduce head injuries when a crash is inevitable. However, today’s motorcycle helmets do not protect equally against all types of head injuries. LÄS MER

  3. 17. Extensions of the kernel method of test score equating

    Författare :Gabriel Wallin; Marie Wiberg; Jenny Häggström; Anton A. Béguin; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Test equating; Nonequivalent groups; Standard error of equating; bandwidth selection; log-linear models; item response theory; Statistics; statistik;

    Sammanfattning : This thesis makes contributions within the area of test score equating and specifically kernel equating. The first paper of this thesis studies the estimation of the test score distributions needed in kernel equating. LÄS MER

  4. 18. Testing for Periodicity and Trend in Long-Memory Processes

    Författare :Abdullah Almasri; Statistiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Statistics; temperature data.; sunspots data; wind speed data; varve data; Siegel’s test; Fisher’s test; periodogram; Fractional difference process; Discrete wavelet transform; operations research; programming; actuarial mathematics; Statistik; operationsanalys; programmering; aktuariematematik; Wavelets; Statistik;

    Sammanfattning : This thesis presents methods of testing the periodicity and trend for the time series, which exhibit dependence over long periods of time. Many such processes can be modeled by a class of models called fractionally differenced processes. LÄS MER

  5. 19. Hydrological Modeling for Climate Change Impact Assessment : Transferring Large-Scale Information from Global Climate Models to the Catchment Scale

    Författare :Claudia Teutschbein; Jan Seibert; Chris Kilsby; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Bias Correction; Climate Change; Climate Models; Ensembles; GCM; HBV; Hydrological Modeling; Precipitation; RCM; Split Sample Test; Streamflow; Sweden; Temperature; Uncertainty; Physical Geography; naturgeografi;

    Sammanfattning : A changing climate can severely perturb regional hydrology and thereby affect human societies and life in general. To assess and simulate such potential hydrological climate change impacts, hydrological models require reliable meteorological variables for current and future climate conditions. LÄS MER

  7. 20. Drum sound from floor coverings - objective and subjective assessment

    Författare :Ann-Charlotte Johansson; Teknisk akustik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vakuumteknik; vibrationer; akustik; hydraulik; Maskinteknik; vacuum technology; vibration and acoustic engineering; hydraulics; acoustic standard; Mechanical engineering; tapping machine; veneer flooring; parquet flooring; binaural recording; foot impact; loudness; sound quality; listening test; paired comparisons; walking sound; drum sound; building acoustics; psychoacoustics; laminate flooring;

    Sammanfattning : Drum sound is the sound produced when an object, such as a foot, hits the flooring in the room in which the receiving ear is located. Drum sound has attracted interest in recent years, particularly due to an increased use of thin floating floor constructions, such as veneer or laminate flooring, which can produce loud and sharp walking sound. LÄS MER