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2707 Uppsatser om Background-noise - Sida 2 av 181
Vi hör inte läraren! ? En enkätundersökning i årskurs sex om upplevd ljudmiljö i skolan
Noise in schools can have negative effect on the teaching environment and speech perception. The national Child Environmental Health Surveys (BMHE) conducted in 2003 and 2011 studied how 12-year olds experience their sound environment in school. Results showed that the number of pupils that experience annoyance from noise increased from 2003 to 2011.Aim: The aim of this study was to study how 12-year olds perceive their sound environment in school.Methodology and material: A quantitative questionnaire survey was conducted in the sixth grade at two schools. The questionnaire used included questions from BMHE and self-produced questions. Sixtynine students answered the questionnaire.Results: Over 50 % of the respondents experience annoyance from noise in school several times a week.
Vegetation och ljudmiljö
Landscape architecture is a visual profession, but other senses also affect our interpretation of a place. Sounds can give us a lot of information about an environment, and they are often perceived as positive. Despite this, research about outdoor sounds most often focus on the reduction of unwanted sounds ? noise ? but the absence of noise does not result in a good soundscape. To accomplish this, sounds we appreciate are needed.
Design of a Direct-conversion Radio Receiver Front-end in CMOS Technology
In this Master's thesis, a direct-conversion receiver front-end has been designed in a 0.18um CMOS technology. Direct-conversion receivers (DCR) have obvious advantages over the heterodyne counterpart. Since the intermediate frequency (IF) is zero, the problem of image is circumvented. As a result, no front-end image reject filter is required and the channel selection requires only a low-pass filter, which makes it easy to integrate directly on chip. However, the DCR also suffers from several drawbacks such as extreme sensitivity to DC offsets, 1/f noise, local oscillator (LO) leakage/radiation, front-end nonlinearity and I/Q mismatch.
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).
Värdet av tystnad : en värderingsstudie över Upplands Väsbybornas betalningsvilja för reducerat flygbuller
Since the spring 2003 the tenant-owner home association the Terrace in Upplands Väsby municipality lies straight under the approach route to Arlanda Airport?s new third landing chute. Noise levels of over 70 dB have been measured in the area, which exceeds National Board of Housing?s, values for traffic noise at a terrace in connection to housing.
By using the method of hedonisk pricing the essay tries to find out if there exists a willingness to pay to reduce the noise in the area.
Dämpning av ljud i Shift-by-Wire växelväljare : Noise damping in a Shift-by-Wire gear shifter
Constantly growing demands from the costumers in the Automotive industry forces the subcontractors to seek alternative ways to compete. One parameter of quality is the components tolerance against NVH(Noise, Vibraion & Harshness) aspects. Kongsbergs Automotive has developed a new gear shifter platform (Shift-by-Wire) that is sold to Alfa Romeo and used in of their car models. However, the company is not pleased with the components sound quality, therefore the main purpose of this thesis is to develope a number of concepts that is supposed to enhance these NVH-aspects.To get an understanding of the problem an analysis of the causes of the emitted sound has been done parallell to a product decomposition, function decomposition and a Ishikawa-diagram. Together with these methods has a litterature study been performed to get familiar with the physics of an impact and especially the emittment of noise.
Strömkontroll till aktiva magnetlager med noggrann och störningsreducerad strömmätning
There is always a need for more effective ways to store energy in order to reduce the human impact on the environment. One step on the way can be the use of flywheels as kinetic energy storage devices. Low frictional losses are essential for a flywheel to be effective. To minimize these losses active magnetic bearings (AMB) can be used to keep the shaft centered instead of the more conventional ball-bearings. AMBs use actuators and a fast control system that needs correct and noise-free measurement data of the shaft position and the current in the actuators to work properly.This thesis explains the process of constructing power electronics and a current measurement system for active magnetic bearings (AMB).
VÄGTRAFIKBULLRETS INVERKAN PÅ UTFORMNINGEN AV BOSTADSBYGGNADER I STADSMILJÖ
The public interest in central living in today?s cities has led to an increasing effect of traffic noise pollution, and today 20% of the inhabitants in Sweden suffer from noise a level that exceeds the limits. At the same time the traffic keeps increasing, and recent researches shows that traffic noise pollution and several of today?s most common health issues are connected, for example, reduction of performance, sleeping issues and cardiovascular diseases. For this cause rules, guidelines and environmental goals has been developed, as well as software?s which calculates the levels of pollution, all this to investigate and improve the environment.
Bil- och järnvägstrafikens inverkan på inomhusmiljön med avseende på ljud och luft : - I planerade bostäder på Haga
NCC has given us a commission to investigate a planned housing area in Haga, Karlstad, situated close to the traffic route Hagaleden and the railway. The housing area consists of one hundred apartments in five different houses. The houses are linked to each other by balconies with glass panels. A long carport is situated between Hagaleden and the housing area to absorb part of the noise from the road. The design of the housing area is creating a silent backyard.
Bilar eller blåmesar? : rehabiliteringsvärdet i Umeås tätortsnära skogar
Nature´s healing capacity is well known and is today an important asset in the protection against stress. Noise problems in cities and it´s green spaces are increasing which in turn provokes stress and in the long term can lead to cardiovascular diseases. To promote people?s health it is important that natural environments have good soundscapes, research show that visiting natural surroundings and listening to sounds of nature promote rehabilitation and relief stress. The purpose of this essay is to determine the value of rehabilitation in forests in Carlshem and Röbäck.
Läsflöde eller läsmöda? : Ett arbete om hur la?sning pa?verkas (och inte pa?verkas) av olika element pa? en webbplats fo?rstasida.
The purpose of this project was to find out how reading is affected, and not affected, by different elements on a start page. The site I was studied belongs to the magazine Fitness Magazine, and the current site has a problem. The editorial texts and articles don?t reach out to the visitors. The goal was to make a proposal for a new first page of the web site that highlights the texts and the reading.With the help of interviews, user testing and textual analysis, I studied if the texts were in itself that caused the problem or if it was the design.
Belastningsregister : En balansgång med den personliga integriteten
At the time of the study, there is no law to prevent an employer from doing criminal background checks. Employers for School and childcare have to do criminal background checks before hiring but the background checks have increased significantly in other industries as well. The aim of this thesis is to analyze and explain what interest employers may have in jobseekers history and how it can affect people?s privacy. To do this I have used right dogmatic approach combined with four interviews with different employers to get their perspective on the subject.
Ljud eller oljud? : planering av goda ljudmiljöer
In our everyday life we are constantly affected by sound; at home, on our way to and from work, when taking a walk through the woods and when we sleep. In discussions about sound one often talk about noise and to what degree a certain noise disturbs us. The positive qualities of a sound and what sounds contribute to the experience of a good environment is rarely discussed.
The question of sound and the quality of sound is given more attention through the expansion of Stockholm, the city is becoming both bigger and more crowded. This raises new questions concerning the planning of the city e.g. should the changes of the sound quality in a place be one of the aspects taken into consideration when planning new buildings, are there ways to improve the sound quality in new building projects? Can we even improve the quality of sound in existing places by simple means?
I have chosen to study four different areas in Stockholm; Hötorget, Mariatorget, Berzeliipark and Norrmalmstorg.
Filter och kapsling för IR-givare
This paper describes the work done trying to diminish the noise present in the signal from an IR-detector. The project was aiming towards two different kinds of applications; heat protection and presence detection. The hypothesis was that the signal-noise ratio would decrease if a filter and a proper installation were used for the detector. Some experiments were executed to determine what kind of filter were the most suitable for each application and how these could be installed. After executing the experiments and evaluate the results we recommend to use a specific filter for each application.
Hörapparatnyttan hos dem som ordinerats hörapparat med öppen anpassning ? En utvärdering
An open fitting is suitable for persons with sloping hearing loss and relatively good low fre-quency hearing. Sensory neural hearing losses often have this type of configuration. A large ventilation canal gives a greater feeling of comfort and less occlusion. The purpose of this study was to look at the hearing aid benefit of open fitted hearing aids. Self report question-naires were sent out to 102 patients who were given ReSound AIR during the year of 2006 in Uddevalla.