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852 Uppsatser om Noise reduction - Sida 2 av 57

Induktiv provning av ferritiskt rostfritt stå

The report examines the factors which may be a contributing cause to the problems that are present when ferritic stainless steel are eddy current tested in a warm condition. The work is carried out at Fagersta Stainless AB in Fagersta which manufactures stainless steel wire. In the rolling mill there is an eddy current equipment for detection of surface defects on the wire. The ferritic stainless steels cause a noise when testing and this noise complicates the detection of defects.Because of this, a study was made of how the noise related to factors such as steel grade, temperature, size and velocity. By observing the signal and with the possibilities to change the equipment settings the capability to let a signal filter reduce the noise level were evaluated.

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.

Bulleremissioner från vertikalaxlade vindkraftverk

Wind power in Sweden is expanding in response to the government's decision that 49% of Sweden's power should originate from renewable energy sources by the year 2020. Problems with noise and sound emissions related to wind turbines are a constant argument against the wind power expansion and this paper means to examine if vertical axis wind turbines might be a viable alternative to the conventional horizontal design for noise sensitive areas. In order to determine factors like difference in frequency, noise propagation and noise emission level, measurements of both horizontal and vertical axis wind turbines have been completed and the data analyzed with MATLAB. It is shown that there is a difference in how the noise from the two types of turbines propagates due to avariation in the frequency spectra of the emitted sound. It is also shown that vertical axis wind turbines generate a lower sound emission with less intensity inthe lower frequencies..

Ungdomars ljudupplevelser i vardagsmiljön

Noise is a growing health problem. People are not always aware of the injuries that noise can cause. The media culture of today has a big influence on teenagers. This is caused by portable music players, computers, concerts etc. The schools are having larg classes and that can cause a lot irrelevant speech during lessons.

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.

Ljudskapande ur ett begränsat perspektiv

The Swedish social insurance agency provides financial support for families and children, but also for people with work injury, illness and at old age. During 2012 they saw the amount of notifications of insurance increasing in Sweden, which is a development that cost our society a great deal of money. With the aim to pursue a sustainable development I have therefore devoted this project to wellness and stress management within preschool.The employees of preschool are often dealing with a lot of stress, due to the big groups of children that causes high noise and sound levels. The high noise and sound levels is a contributor to stress which additionally can damage the health and cause impaired hearing loss. About half of the people around their forties until the age of retirement have difficulties understanding speech in large groups.The purpose of this project has been to investigate the causes of negative stress for my target group, women between 30-60 years old who works in preschool.

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.

Solel från ljudbarriär : längs Annetorpsvägen i Hyllie, Malmö

City of Malmö has ambitions for the district Hyllie to become a demonstrative area ofsustainable urban development. As a part of this the following report aims to investigate the potential in using noise barriers combined with photovoltaics along Annetorpsvägen to generate solar electricity. To quantify the losses that shadows from buildings along the roadmight cause, a 3D-model of the area was constructed in SketchUp. This digital model made it possible to simulate shadows and how they change over the year. A reference model of a photovoltaic noise barrier (PVNB) was constructed and used to find the dates on which the solar cells are shadowed depending on building heights and positioning of the barrier.The results show that two lengths with a total distance of 400 meters is appropriate for applying photovoltaic noise barriers.

Bakgrund - No?t - Lycka : en genomga?ng av musikens betydelse i mitt liv samt arbetsprocessen fo?r musikskapandet

The Swedish social insurance agency provides financial support for families and children, but also for people with work injury, illness and at old age. During 2012 they saw the amount of notifications of insurance increasing in Sweden, which is a development that cost our society a great deal of money. With the aim to pursue a sustainable development I have therefore devoted this project to wellness and stress management within preschool.The employees of preschool are often dealing with a lot of stress, due to the big groups of children that causes high noise and sound levels. The high noise and sound levels is a contributor to stress which additionally can damage the health and cause impaired hearing loss. About half of the people around their forties until the age of retirement have difficulties understanding speech in large groups.The purpose of this project has been to investigate the causes of negative stress for my target group, women between 30-60 years old who works in preschool.

Vad ha?ller da?ren vaken om na?tterna? : utforskande av det ogripbara

The Swedish social insurance agency provides financial support for families and children, but also for people with work injury, illness and at old age. During 2012 they saw the amount of notifications of insurance increasing in Sweden, which is a development that cost our society a great deal of money. With the aim to pursue a sustainable development I have therefore devoted this project to wellness and stress management within preschool.The employees of preschool are often dealing with a lot of stress, due to the big groups of children that causes high noise and sound levels. The high noise and sound levels is a contributor to stress which additionally can damage the health and cause impaired hearing loss. About half of the people around their forties until the age of retirement have difficulties understanding speech in large groups.The purpose of this project has been to investigate the causes of negative stress for my target group, women between 30-60 years old who works in preschool.

En skrivarstuga, en inspelning och en film : skriftlig reflektion inom sja?lvsta?ndigt, konstna?rligt arbete

The Swedish social insurance agency provides financial support for families and children, but also for people with work injury, illness and at old age. During 2012 they saw the amount of notifications of insurance increasing in Sweden, which is a development that cost our society a great deal of money. With the aim to pursue a sustainable development I have therefore devoted this project to wellness and stress management within preschool.The employees of preschool are often dealing with a lot of stress, due to the big groups of children that causes high noise and sound levels. The high noise and sound levels is a contributor to stress which additionally can damage the health and cause impaired hearing loss. About half of the people around their forties until the age of retirement have difficulties understanding speech in large groups.The purpose of this project has been to investigate the causes of negative stress for my target group, women between 30-60 years old who works in preschool.

Taluppfattningstest med enstaviga ord i brus: Normalvärden för barn i åldrarna 7, 10 och 13 år

Background: Phonemically balanced word lists are used when obtaining speech recognition scores in noise. These lists are designed for adults, but are still used for children. To properly obtain speech recognition scores in noise for children, normative data is needed to show what differences there are to be expected between children of different ages. Purpose: The main purpose is to obtain normative data for children in the ages of 7, 10 and 13 years for speech recognition scores in noise using words and to compare these with each other and with normative data of adults. A further purpose is to examine if there is any practice- or exhaustion effect to be seen when obtaining speech recognition scores in noise for children in the ages of 7, 10 and 13 years.Material: The participants were ten 7-year-olds, ten 10-year-olds and ten 13-year-olds.

Design och medveten närvaro : Ljusets förmåga till stressreducering och uppmuntran till medveten närvaro i förskolan.

The Swedish social insurance agency provides financial support for families and children, but also for people with work injury, illness and at old age. During 2012 they saw the amount of notifications of insurance increasing in Sweden, which is a development that cost our society a great deal of money. With the aim to pursue a sustainable development I have therefore devoted this project to wellness and stress management within preschool.The employees of preschool are often dealing with a lot of stress, due to the big groups of children that causes high noise and sound levels. The high noise and sound levels is a contributor to stress which additionally can damage the health and cause impaired hearing loss. About half of the people around their forties until the age of retirement have difficulties understanding speech in large groups.The purpose of this project has been to investigate the causes of negative stress for my target group, women between 30-60 years old who works in preschool.

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.

Kärnkraft : Ett arbete för drifttekniker?

The gas turbines in the Swedish secondary reserve are reaching the end of their technical lifetime, hence alternative solutions need to be considered. One of the solutions thought to have the greatest potential is the use of so called consumptionreduction. By entering contracts with large consumers, agreements are made to reduce consumption in the event of major disturbances in the power system and thus being used as a secondary reserve. This thesis investigates the feasibility of consumption reduction as part of the secondary reserve. This has been achieved by developing a requirement specification for the disturbance reserve and by studying the technical and economic potential for consumption reduction among a range of consumers.The technical potential for consumption reduction that fulfils the requirements for participating in the secondary reserve are on average 750 MW in SE 3 and 98 MW in SE 4.

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