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313 Uppsatser om Cabin noise - Sida 12 av 21
Avblås för torkning av kabel
This report is written on the assignment by Nexans IKO Sweden AB in Grimsås which is a cable manufacturing company. Nexans IKO Sweden AB was in need of help to examine possibilities for saving energy by saving compressed air, in first place by using the compressed air more efficient. The task was to determine the present situation, making the airwipe stations more efficient by reducing the consumption of the compressed air and in turn save money. Even the aspects of the working environment were discussed as the noise levels from the pneumatic systems and engines are usually high. A schedule over the airflow in the factory and the inventory over current airwipessituation was made.
Passivhus med prefabelement : En jämförelse mellan en platstillverkad konstruktion och prefabelement från Masonite Lättelement AB
This thesis conducted at the University of Uppsala investigateshow well a prefabricated building component from the manufacturerMasonite Lättelement AB can be incorporated into ahouse projected to accomplish the demanding criteria of a passivehouse. The thesis is organized as a comparison betweenthe prefabricated elements and an on-site built component fromthe passive house area of Oxtorget in Värnamo, Sweden. Theaspects investigated were air leakage, energy, moisture, economyand noise conditions.Results of the comparative analyzes shows that the prefabricatedproducts were capable of accomplishing the requirementsof passive houses and therefore this thesis should beviewed as a basis to confirm that the technology of prefabricatedbuilding components today in Sweden are mature enoughto be a significant part of the passive houses that are to be builtin the near future. The development of prefabricated technologyis of crucial significance if we are to accomplish the goalsof reduced energy consumption by the year 2020..
Effektiv betong för småhusproduktion : Betong med högt luftinnehåll för platta på mark
This Masters thesis work describes a comparison between two different methods for estimation of the down channel (base station to mobile subscriber) in Wide-band Code Division Multiple Access (WCDMA). The first estimation method, Optimal Feed-forward Channel Estimation (OFCE), is a conventional method that bases the estimates on data that is known to both sender and receiver, so called pilots. The second method, Decision Directed Channel Estimation (DDCE), is an elaboration of OFCE. It also uses user data for estimation. Simulations show that DDCE, in comparison to OFCE, does not attain an improvement in signal-to-noise-ratio (SNR) for high bit error rates (BER).
Går det att säkerställa ljudmiljön i en träningslokal? - en studie om ljudnivåövervakare på träningslokaler i Göteborg
In Sweden, exercise takes a great part in people?s lives. Health and a good conditioned body go hand in hand. Many Swedes exercise in groups, with aerobics or a similar form of workout at a training facility. A regular workout lasts for about an hour and is accompanied by music.
Delta X : Utveckling av värmeväxlare
Stockholms vattenskärning AB in Kungsängen has through the acquisition of a company begun to design and produce aircraft heaters whose origin is early 1970s which follows a high inefficiency in terms of energy consumption and size.The aircraft heater, which is sold worldwide, serves its purpose for customer satisfaction and has done so ever since it was developed in the 70s.Stockholms vattenskärning AB is now investigating the possibility in making the aircraft heaters more efficient, both in terms of energy consumption but also on a more efficient design with the belief that it would lead them to an edge in the market. The aircraft heater consists of several main components whose function altogether is to keep passenger aircrafts warm while they are on the ground.This project has been limited to the further development of the heat exchanger package which accounts for the conversion of the hot medium to the fresh air being carried in to the aircraft cabin. Work has been divided into different phases in order to create a better understanding of the project range and to make it easier to divide the various elements in the time available, 10 weeks. These phases are literature review, situation analysis, concept generation, CAD, concept comparison and writing reports.After the initial literature review was made, a fundamental theory was written which is essential in understanding the remaining parts of the project.With the theoretical part as support, measurements and calculations were made on the current heat exchange package in a situation analysis to ensure its operation and efficiency.In the concept generation phase, the collected facts from the literature review was used as the basis for creating a matrix. The purpose of the matrix was to indicate the two most suitable types of heat exchangers to develop four new concepts out of.In the CAD phase the four concepts was drawn up and then described with text and images.The last phase is the concept comparison where a concept selection matrix is used to function as a decision basis for further production at Stockholms vattenskärning AB. The four concepts have been developed based on the current heat exchanger and is gradually changed into a design of a cross-flow heat exchanger constructed out of stainless sections. The purpose of this is to have gradual upgrading of the heat exchanger as an option, in order not to saturate the market..
Betongbjälklag med limmad matta : olika behandlingars effekt på alkalitet, fukthalt och emissionsbildning
This Masters thesis work describes a comparison between two different methods for estimation of the down channel (base station to mobile subscriber) in Wide-band Code Division Multiple Access (WCDMA). The first estimation method, Optimal Feed-forward Channel Estimation (OFCE), is a conventional method that bases the estimates on data that is known to both sender and receiver, so called pilots. The second method, Decision Directed Channel Estimation (DDCE), is an elaboration of OFCE. It also uses user data for estimation. Simulations show that DDCE, in comparison to OFCE, does not attain an improvement in signal-to-noise-ratio (SNR) for high bit error rates (BER).
De akustiska skillnaderna mellan två städer i Sverige
Studien bygger på två 24 timmars ljudinspelningar utförda från två olika städer iSverige. Syftet med undersökningen var att se om det gick att urskilja akustiskaskillnader mellan två olika städer i Sverige. Studien har tagit mycket inspiration av R.Murray Schafer arbeten inom soundscaping, samt Pijanowskij, et al., (2011) ramverkför att kunna kategorisera ljuden utifrån dess ursprung och funktion. Olikaundersökningar har genomförts med hjälp av kvalitativa intervjuer, samtfrekvensanalyser av det inspelade materialet. Båda metoderna användes tillsammansvid utvärderandet av ljudmaterialet för att se hur vida informanternas svaröverrensstämde med den frekvensanalys som genomförts.
Dämpning av fläktljud i diskmaskin
Detta examensarbete omfattar akustiska undersökningar utav en desinficerande diskmaskin av typ Getinge 8666/8668 och har utförts på Getinge Desinfection AB i Växjö. Vi har undersökt hur man med enkla medel kan sänka ljudtrycksnivån i maskinens närhet. Mätningar har utförts på diskmaskinens torkprogram, där torkfläktarna är de mest dominerande ljudkällorna och ljudet främst är luftburet. En systematisk analysmetod bestående av införandet av successiva dämpningsåtgärder visade att de dominerande ljudvägarna går via taket, golvet samt till viss del spalter i maskinens väggar. Genom att isolera både tak, golv och spalter kunde ljudtrycksnivån sänkas med totalt hela 5,9 dB.
Estimering av GPS pålitlighet och GPS/INS fusion
The global Positioning System (GPS) provides location and time information as long as there are unobstructed lines of sight to four or more GPS satellites. However, when this is not the case the signal may be inaccurate or sometimes even completely blocked. In these situations the Inertial Navigation System (INS) is an appropriate choice for positioning. An INS has already been proposed in a previous thesis by Erik Andersson and the objective of this thesis is to fuse the GPS with the INS in a proper way. A part of this project is to decide the reliability of the GPS.Three methods for GPS reliability detection have been proposed. One method based on the statistical properties of each of the separate systems, and two methods based on the statistical properties of the residuals between the GPS and INS.
Den ljudlösa bilen : En underso?kning om buller, ba?ng och brummande bilar
Examensarbetet kommer underso?ka aktiv ljuddesign fo?r tysta personbilar. Utifra?n tidigare forskning om hur elbilen utsa?tter ma?nniskor i ta?tomra?den fo?r fara pa? grund av avsaknaden av auditiv information, ska vi utveckla fo?rslag pa? dynamiska billjud som fo?rha?ller sig till trafiksa?kerhet, design och minskade ljudfo?roreningar. Den totala ljudniva?n i sta?der a?r la?ngt o?ver rekommendationen och fo?ljden blir ett ha?lsoproblem i sto?rre sta?der.
Den sista vilan : vad kännetecknar en rofylld begravningsplats?
This essay examines the criteria for a peaceful cemetery. First there is a short history of the Swedish funeral place. After that follows the definitions of a peaceful place according to environmental psychology. From these definitions an analysis method is constructed for identifying a peaceful cemetery. The analysis method contains six criteria, shape of the entrances, existence of sound, vegetation character, the cemetery?s demarcation, the cemetery?s management and what feeling the cemetery mediates.The analysis method is put into practice on three cemeteries, Överklinten cemetery, Stockholm forest cemetery and the old cemetery in Malmö.
Hur påverkar byggnadsmaterial av stål en induktiv hörslingas fältstyrka samt frekvensgång?
This research analyzed differences in measurements of magnetic field strength and frequency response in five audio induction loops installed in rooms of wooden construction materials and five audio inductive loops installed in rooms of steel reinforced concrete constructions. The inductive loops were installed at floor level and the measurements were made at the listening height of 1.2m. Measurements of background noise, field strength and frequency response were made at fifteen different measurement points across the room. The research measurements showed that there are differences in field strength and frequency response between these two conditions, whether the audio induction loop is installed in a wooden construction or the audio induction loop is installed in a reinforced concrete construction. The results had a significance level of p=0,05..
Undersökning av mätsystem och regulatorstrukturer för industriella tillämpningar
This thesis is divided in to two different parts. The first part includes examination of the measurementsystem of an industrial robot using a resolver sensor. The main focus is on methods for suppressing noise in the angularvelocity signal without increasing timedelay. Five different methods are investigated. Three of these are based on oversampling: burstsamplingmethod, meanvaluemethod and correlationmethod.
Skolans utformning, ett hinder för lärares eget lärande? : En studie av den fysiska arbetsmiljöns påverkan på lärares eget lärande
This essay is written about how the physical environment affects teachers? own learning. The purpose is to see how the teachers? work is affected by various factors, such as the uses and placement of the teachers? offices, common room, or any other places where a meeting may occur. The survey was conducted using both interviews and observations of the teacher?s office.
Kan man minska bilåkandet i staden? : sett ur ett stadsplanerarperspektiv
The reason why this essay is written can be parted in two, whereas one would be the global trend of urbanization that occurs to this moment and forward, whereas the other would be the debate of how motorism has come to be an issue of sustainable management of our cities and our environment. In purpose to deliver a thorough understanding of how the car and its capacity has come to shape the society of today, and to emphasize the problems it´s brought, a historical survey has been made, followed by the report of problems to the society formed by the needs of the car, discussed in several environmental issues, such as jamming, noise and air pollution. This is followed by the discussion of potential solutions for how city planning could return to the focus of the human scale and perspective, in purpose to correspond with the issue of ways to decrease the car use in towns. In conclusion, the given solutions are discussed, where examples like shared space, investment in public transport, mobility management and the theory of the assembled city are included, with aid from literature, to finally conclude the essay with personal thoughts of how the planning of today, or the given solutions, really are the result of sustainability for city planning from a human perspective.