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245 Uppsatser om Acoustic signals - Sida 3 av 17

Design av stimuligenerator för radarmålsökare

During the development of microwave based sensors such as radar target seekers, input signals are needed to verify the performance of the system. Therefore, a channel board has been developed by previous thesis projects at Saab Bofors Dynamics. It uses a technique called Digital Radio Frequency Memory (DRFM). The purpose of this board is to sample and digitally store radio frequency signals in order to reconstruct them after a certain delay.The aim of this thesis project was to use the channel board named above to construct a portable instrument for generation of stimuli signals. This assignment has been divided into two tasks: firstly, to construct and put together the hardware components and secondly, to implement a graphical user interface for the instrument.

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).

Adaptiv temperaturreglering av bostadshus

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.

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.

Fysiska strukturer i Umeälvens gamla älvfåra och dess inverkan på laxsmoltens utvandringsframgång

The survival of hatchery reared smolts is generally low after release. To get a better understanding of what variables affecting migration success, Atlantic salmon smolts were studied during their out-migration in the old river channel in the lower part of river Umeälven. The area consists of shifting habitat and complex structures which causes difficulties for smolt on their migration out to sea. The aim of this study was to try to determine the effects of feed restriction, fin conditions and different physical barriers in the river, on the migratory behavior of Atlantic salmon smolts in the river Umeälven. The river was divided into six different sections using acoustic receivers strategically deployed along the river. Two-year old hatchery-reared smolts (n=150), in three different weight classes, were tagged with acoustic transmitters.

Synsätt på barn och barnboken. Vilka signaler har barnbiblioteken fått under 1900-talet?

The aim of this masters thesis is to examine what intentions handbooks, laws and regulations have had about children and childrens literature, as we think that they can serve as guiding principles for childrens libraries in Sweden. The questions are: what signals have the childrens libraries got from the documents concerning the view of children and childrens literature during the 20th century? What has the social opinion about children been during the 20th century? How have children been seen during the 20th century? The method we used is a qualitative source analysis of mention above documents seen from a hermeneutical point of view. This analysis is woven together with the social opinion on children during the 20th century. Our results show that the aim of childrens literature before 1945 was a pedagogic and moral one.

Image follows structure

Background: The business market today is characterized by tough competition amongst the competitors to capture consumers? interest and money. One marketing tool companies can use to achieve this is the company?s image. The customer buys not only a product, but also the image that the company or the product is associated with.

Kattens naturliga beteende och hantering av katt på klinik

This literature study investigates the natural behaviour of the cat and handling of cats in the clinic. A presentation of tactile, olfactory, visual and acoustic communication is given. The reproductive behaviour of the cat is explained and the development of kittens is described. The study highlights hunting behaviour, territory structures and social life of cats. The report also includes practical instructions to how the environment and handling of cats in clinics can be improved..

Könsstereotyper i reklam, Gender stereotypes in commercials : En analys av genus i ICAs och H&Ms reklam, gender analysis of the commercials from ICA and H&M

We are constantly being fed information. Everything and everyone we come into contact with may somehow make a new impression on us, whether we are aware of it or not. One of the ways that people in today?s society in Sweden are being given information is via different types of media, for example through commercials. Whether it?s a video clip or a still-frame picture, a commercial is an effective way for a company to reach out to potential customers.However, it is not only the messages or signals that may appear obvious that these companies send out when advertising with commercials.

Konstruktion av datainsamlingskort för mätsystemet COMET

During test flights SAAB uses the data acquisition system COMET 16. The part of the system that receives the signals from the sensors and converts them is called KSM 15. The purpose of this thesis is to develop a data acquisition module on stacked PC/104 modules with a lower production cost. Our work has been divided into one part about analog signal conditioning and a second part with digital filtering and memory management of the sampled data. The analog part, designed of regular components like instrument amplifiers, voltage references, operational amplifiers and multiplexers, adjusts the sensors signal levels for the ADC?s that converts the signals.

Modellbaserad prediktiv reglering av en dieselmotor med variabel geometriturbin och återcirkulering av avgaser

Control of a diesel engine equipped with Variable Geometry Turbine (VGT) and Exhaust Gas Recirculation (EGR) requires a multivariable control method. One problem is that the engine system is non-linear. Furthermore there are strong cross-connections between inputs and outputs and the inputs have alsoboundaries. To be able to manage these control problems, MPC has been used that is a multivariable method. The MPC-controller consists of an optimization problem and therefore MPC can find the optimum control signals in an easy way.

Analog-to-Digital Converter Design for Non-Uniform Quantization

The thesis demonstrates a low-cost, low-bandwidth and low-resolution Analog-to- Digital Converter(ADC) in 0.35 um CMOS Process. A second-order Sigma-Delta modulator is used as the basis of the A/D Converter. A Semi-Uniform quantizer is used with the modulator to take advantage of input distributions that are dominated by smaller-amplitude signals e.g. Audio, Voice and Image-sensor signals. A Single-bit feedback topology is used with a multi-bit quantizer in the modulator.

Ledningsarbetet hos ett krisföretag : en analys av ledningens hantering av en ekonomisk kris

Almost every company sooner or later ends up in a more or less difficult economical situation. The reason for the economical crisis varies for each individual case but common for them all is that it is the management group that has failed in their work to guide the organisation to avoid a negative result. The next common denominator is that it is the management group that has to handle the changes in the company's environment and lead the company out of the crisis. But how can they do this and take decisions in a rational and effective way and is there warnings signals that the management group missed before the crisis was a fact? This is some of the questions that this study is going to discuss and analyze. The aim of the study is from a management perspective chart the strategic work of the company's management work when handling an economical crisis.

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..

Radiolänk med GNU Radio

At the Department of Technology and Built environment at the University of Gävle there was an interest to study GNU Radio, which is an "open source radio project. The project is based on that most of the radio signal processing is made in an ordinary PC. The idea behind this degree project was that in a laptop there are several radio transmitters/receivers that takes space, generates heat and transmit in varied frequency band etcetera. All these radio transmitters/receivers could be replaced with a Software Defined Radio system. It means that one common, general radio hardware is used to different communications such as: WLAN, Bluetooth, GPRS, 3G etcetera. The waveform is generated in the software, which makes the system very flexible.

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