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8755 Uppsatser om Acoustic analysis - Sida 1 av 584

Perception of human acoustic communication in the domestic dog (Canis familiaris)

For most dog owners today it is natural to use acoustic stimuli such as talking to communicate with their pets. Words are used both to ask the dogs to perform tricks, as well as to hold ?conversations? with the dog. This literature review looks at how dogs perceive human acoustical communication and how this can influence the behaviour of the dog. This information could be used e.g.

Går det att mäta blodtryck med fotopletysmografi och bioakustisk sensor i kombination?

The aim of the work was to investigate the possibility to combine information from PPG and bio-acoustic technology to extract information that is related to the blood pressure. The measurements have been carried out with several different configurations. First the relation between arterial sounds and the PPG-signal was studied. After those measurements with both PPG and the bio- acoustic technique was concluded on people in different positions and after riding a bike. The goal was to vary the blood pressure.

Perceptuell och akustisk bedo?mning av ro?stfunktion hos barn med tonsillhypertrofi : Effekter av kirurgi

In Sweden over 10.000 patients annually, mostly children, undergo tonsillar surgery. The most common surgical method is total removal of the tonsil, tonsillectomy (TE). During the last decade partial tonsil resection, tonsillotomy (TT), has been reintroduced and is associated with lower primary morbidity and less postoperative pain. The aim of the present study was to evaluate if and to what extent 4-5 year old children?s voice function are affected by tonsillar hypertrophy compared to controls and to study the effects of the two surgical techniques on vocal function.

Tuftade ljudabsorbenter ? väggpaneler för rumsliga och akustiska egenskaper

It is a well-known fact that textiles and carpets have benign sound-absorbing properties. It is desirable to have quantified values of these properties ? especially for architects and interior designers. They often need to be able to giveaccount for the acoustic properties of their designs at a relatively early stage and sometimes have strict acoustic classifications imposed upon them by their contractor. A product with documented acoustic properties would aid when prescribing interior elements.The purpose of this thesis is to develop a wall-mounted panel in hand-tufted material ? aesthetically pleasing and versatile but also having documented and quantified acoustic properties.

Akustisk mätning av U-värde

This pre-study investigates the possibility of U-value measurements through an acoustic method. A hypothesis about an acoustic model built on acoustic theories combined with U-value theories is presented to answer the questions: ? Can U-value theory be combined with acoustic theories? ? Can the coefficient of heat be affirmed trough an acoustic measurement? The idea for this dissertation begun with a logical idea in mathematical similarity, between the coefficient of heat transmission units and sound intensity units. The U-value theory is based on assumptions such as initial resistance for inner walls and initial resistance for outer walls. The resistance in the material is interpreted through sound intensity theory. The argument is built upon mass law theory, which means if the frequency or thickness of the material layer doubles it implies an increase of sound reduction by 6 dB.

Passive acoustic diver detection

This report discusses a method to detect divers in harbour environments usingpassive acoustic detection. The goal was to achieve as high detection as possiblewithout having too high false alarm rate. A short execution time was also desirable.By using the characteristic of an inhalation a band-pass filter was applied to the signalto improve the signal to noise ratio. After the filtering an energy estimation of thesignal was made. This energy estimation was later used in a frequency analysis, whichcould tell us if there were enough energy in the frequencies that correspond to adivers breathing frequency.

Akustiskt åtgärdsprojekt av en rockmusikklubb där live-musik spelas. Vad kan en audionom bidra med?

Introduction: The number of hearing impairments in Sweden is increasing. The largest increase is seen in ages 25-44. There are reasons to believe that these impairments are noise induced. Leisure time noise is not controlled in the same manner that industrial noise is. An ongoing conflict between city council officials and rock club owners, musicians and music event organizers about sound levels at smaller live music clubs exceeding the national sound level restrictions created the need for an acoustic intervention project.

Kommunikation mellan två medium

The aim of this project is to find a concept solution for a wireless transmitting system, installed to transmit data from a hydrophone of the ocean floor down by a wave power generator to the office on shore. The project is a literature review in which previous observations and tests are analyzed and put together to find a solution. The result was a comprehensive solution that includes an acoustic modem to transfer captured information from the bottom to the surface, wirelessly through the water. The information is then sent fron the surface on radio waves through the GSM network to the office on land. Between under and over water there are components to convert information between acoustic waves and radio waves, but also various types of modulation, such as amplitude and frequency modulation is required..

Analys av Svartlut med Aktiv Akustisk Spektrometri : Analysis of Black Liquor with Active Acoustic Spectrometry

Vid kemisk massatillverkning finns behov av mättekniker som möjliggör ytterligare optimering av processen. Möjligheten att analysera svartlut med hjälp av aktiv akustisk spektrometri utreddes genom att ett online instrument konstruerdes och installerdes på ett pappersbruk. Analyser med multivariata metoder utfördes på resultaten. På grund av yttre omständigheter försenades arbetet, och ett tillräckligt dataunderlag för en definitiv slutsats erhölls ej. En rad vidare arbeten föreslås..

Åtgärder för att minimera trafikbullers påverkan på ett rekreationsområde

The aim of this inquiry was to investigate the most appropriate measures to reduce noise impacts from road traffic on the Nydala recreational area in Umeå municipality due to the planned re-routing of the E4 motorway to an existing road along this area. The sound environment is an important part in the experience when we are visiting recreational areas. Noise is not only disturbing; the liberty from unwanted sounds also allows us to perceive natural sounds that are a benefit for the cultural experience. Therefore it is important to take actions to protect this well used area from traffic noise. The reasonable options to avoid noise impact in this case are to lower the speed limit, using a noise reducing coating or use noise protection screens and walls.

Analys av ljudspektroskopisignaler med artificiella neurala eller bayesiska nätverk

Vid analys av fluider med akustisk spektroskopi finns ett behov av att finna multivariata metoder för att utifrån akustiska spektra prediktera storheter såsom viskositet och densitet. Användning av artificiella neurala nätverk och bayesiska nätverk för detta syfte utreds genom teoretiska och praktiska undersökningar. Förbehandling och uppdelning av data samt en handfull linjära och olinjära multivariata analysmetoder beskrivs och implementeras. Prediktionsfelen för de olika metoderna jämförs och PLS (Partial Least Squares) framstår som den starkaste kandidaten för att prediktera de sökta storheterna..

Barnröstens förändring under dagen i en anpassad röstinspelning och spontantal : En experimentell studie av perceptuella och akustiska parametrar

A controlled recording in a studio is the basis of all voice treatment. However, this controlled way of recording voice patients' voices can be questioned. The voice use may be different in a natural environment. In children noise related voice problems are investigated in a study about voice and its development (BUG ? Child voice and noise).

Skogens Eko

Naturen inspirerar mig, i detta projekt jobbar jag med strukturen hos trädstammar och bark, och översätter det jag ser till vävda textiler. När jag befinner mig i naturen känner jag mig ofta lugn och kan koppla bort allt annat i min omgivning. Det lugnet vill jag återskapa och föra in i en rumslighet. I barkens olika strukturer såg jag intressanta varierande ytor som jag ville jobba med i textil. I mitt examensarbete har jag designat textilier med uppmätt akustiska egenskaper för offentlig miljö.

Röst och hörselnedsättning : Akustisk analys av röst hos sju hörapparatsanvändare

A number of studies have been made to examine several aspects of voice production in individuals with different types of hearing impairments. Most of the studies were made to explore the impact that hearing aids have for people with severe or congenital hearing impairment. So far it has been confirmed that there are changes regarding voice production in these individuals. A group that has not been investigated regarding voice production to a larger extent are hearing aid users with an acquired hearing impairment. In the present study the voice production of seven individuals, four men and three women, with a moderate acquired hearing impairment is examined.

Optimering av informationsinsamlingvid prototyptillverkning

This report discusses a method to detect divers in harbour environments usingpassive acoustic detection. The goal was to achieve as high detection as possiblewithout having too high false alarm rate. A short execution time was also desirable.By using the characteristic of an inhalation a band-pass filter was applied to the signalto improve the signal to noise ratio. After the filtering an energy estimation of thesignal was made. This energy estimation was later used in a frequency analysis, whichcould tell us if there were enough energy in the frequencies that correspond to adivers breathing frequency.

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