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1072 Uppsatser om Audio Frequency Track Circuit - Sida 23 av 72
Undersökning av vissa beläggningars påverkan på antenners effektivitet i tågmiljö
For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.
Tuta i lurendrejeri
Purpose: Exploring the relatively new technology of convolution reverb, to gather knowledge on its limitations when used practically in the production of pop music, and from these findings to learn about applications in other performing arts and sound design.
Methodology: This is a case study of creating convolution reverb by doing impulse responses (IR) and then applying them to studio recorded pop music. The empirical data consists of the final song results, notes and journals from during the process and the comparisons, as well as established litterature on acoustics, psycho-acoustics and music production.
Results: Convolution reverb can widely and freely be used in the production of music and other audio-based art forms, since our study shows that the result of a well-made impulse response from a particular room is indistinguishable from music that is actually played and recorded in the same space..
Implementering av Patientsimulator för Anestesimaskiner
In order to facilitate testing of anesthesia machines a patient simulator has been required by Maquet Critical Care AB. A patient simulator has been developed to reduce expensive and time consuming animal experiments and temporary lab arrangements. The patient simulator has been developed and designed to simulate human lungs with regards to anesthetic uptake, production of carbon dioxide and heating and moisturizing exhaled air.The system comprises a container and a test lung to simulate the volume and the dynamic of the human lung. The simulation of uptake of anesthetics has been implemented by pumping a fraction of the gas from the container through a bypass circuit with an active charcoal filter that adsorbs volatile anesthetics. The flow through the bypass circuit is generated by a pump and is controlled by a linear valve.The resulting performance of the patient simulator has fulfilled the requirements.
Aktiv bullerdämpning i ventilationssystem
Active headsets have been on the market for years and now it is time for something else to enter the stage. The technology of active noise reduction can for exmple also be used in ventilation systems for reducing ventilation noise. An active control system principally consists of four important components, namely the downstream error microphone, the upstream detection or reference microphone, the digital signal processor (DSP) and a loudspeaker. The upstream reference microphone listen to the primary ventilation noise and sends it to the DSP which makes a phase shift to the signal and sends it to the loudspeaker. The loudspeaker sends out the opposite waveform of the incoming one and reduce the primary ventilation noise.
Analys av skillnader mellan internationell och svensk rapportering av inträffade händelser på kärnkraftverk
Report of diploma work conducted at the Swedish Radiation Safety Authority (SSM) as part of the bachelors program in Nuclear Engineering at Uppsala University.All nuclear power plants in Sweden are obliged to report any deficiency in their barriers or the defense in depth in obedience to SSM?s regulations concerning safety in nuclear facilities. In addition, there is an international system for reporting such events. The purpose of this thesis is to study the Swedish report system and to analyze the differences between Swedish and international event reporting.In the Swedish system, SSM?s regulations are effectuated by means of event reports classified as category 1-3, designed individually at each Swedish facility.
Animerad kortfilmsproduktion
Arbetet är uppdelat i två delar. Den första handlar om min egen medverkan i kortfilmen O Trovão och hur organisationen och planeringen runt filmen är upplagd. Den andra delen handlar om animationsbranschen och olika landers marknader for animerad film och tv. Den innefattar också två intervjuer med kortfilmskapare. I kortfilmsproduktionen har jag tillsammans med teamet gått igenom de första faserna i produktionen, från planering och research, till koncept och modellering.
Ägande/ övertagande av IKN-nät : fördelar, nackdelar, för industri och nätbolag
Syftet med detta examensarbete var att underso?ka MEMS och elektretmikrofoner fo?r att finna vilken typ som la?mpar sig ba?st fo?r fo?retaget Comfort Audio AB och deras ho?rselhja?lpmedelsprodukter. Uto?ver detta underso?ktes mo?jligheter att kontrollera upptagningskarakteristik med hja?lp av en teknik vid namn end-fire.Resultaten har erha?llits genom att underso?ka ett antal elektroakustiska egenskaper hos olika mikrofoner, som sedan har ja?mfo?rts med respektive tillverkares tekniska specifikationer. Upptagningskarakteristiken har underso?kts genom konstruktion av en mikrofonuppsa?ttning da?r den summerade signalen underso?kts.
Mätningar och analys av elnätet hos FHP, Basproduktion
This report is a degree project performed at Freudenberg Household Products AB, (FHP). The degree project comprises measurement and analysis of the power net at FHP Basproduction. The content is divided between one theory-part, one document- part with measurements and also conclusions and a list of measures to be taken. During the project the purpose and restriction change from a quality investigation to only concentrate on harmonics and finding the reason why they exist, and also to find a solution to the problem with harmonics. The measurements shows that the power net contains harmonics of different order and intensity.
Bedömning av utländsk brytning och förståelighet hos personer med svenska som andraspråk före och efter en kurs i svenskt uttal
There is a lot of research made on second language (L2) learning (Jesney, 2004). However the relationship between foreign accent, intelligibility and acoustics within pronunciation tutoring is quite an unresearched area (Thorén, 2008). The aim of the study was to analyze how a course in Swedish pronunciation affected foreign accent, intelligibility and acoustics among L2-learners of Swedish. A total of 41 people participated in the study: 16 L2-learners, 4 native Swedish speakers consisting a control group and 21 perceptual assessors with Swedish as native language. The L2-learners foreign accent and intelligibility were rated by the listeners before and after a course in Swedish pronunciation on an eight-point Likert-scale.
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.
Interaktiv skrivtavla i undervisning : En multimodal fallstudie av en lärares användning av interaktiv skrivtavla i läs- och skrivundervisning
The aim of the study is to investigate how a teacher uses multimodal resources with an interactive whiteboard while teaching reading and writing. The aim is also to investigate what view the teacher has on using an interactive whiteboard while teaching reading and writing. Video-recorded observations and audio-recorded interviews are the methods used to collect data. The analysis was performed from a multimodal perspective and is also inspired by interaction analysis. The result of the analysis showed that the teacher uses several multimodal sign systems in combination with those found on the interactive whiteboard.
Aktiv bullerdämpning i ventilationssystem
Active headsets have been on the market for years and now it is time for
something else to enter the stage. The technology of active noise reduction can
for exmple also be used in ventilation systems for reducing ventilation noise.
An active control system principally consists of four important components,
namely the downstream error microphone, the upstream detection or reference
microphone, the digital signal processor (DSP) and a loudspeaker.
The upstream reference microphone listen to the primary ventilation noise and
sends it to the DSP which makes a phase shift to the signal and sends it to the
loudspeaker. The loudspeaker sends out the opposite waveform of the incoming
one and reduce the primary ventilation noise.
Mikrosensorer i nätverk
The purpose of this thesis is to investigate the possibility to make small, cheap and ultra low power sensor platforms, connected in wireless networks for monitoring of home and industrial environments. The concept is based on ideas from our supervisor, Jerry Lindblom. The developed system consists of a generic platform for different sensors, a receiver and software. A GPRS module from RO Rollytech AB and a database from Gema Industri AB have been modified and used to demonstrate an example of a complete system. To the platform, it is possible to connect any resistive sensor and any sensor that can act as a switch.
Effektiviseringspotential inom industrisektorn : Energibesparing vid frekvensstyrning av centrifugalpumpar ? en fallstudie
The project was performed at SiemensIndustry Drive Technologies with theobjective to provide actual values forthe energy savings potential withinSiemens scope of practice.In Sweden the electrical drives standfor about 30 % of the total electricityconsumption and about 60 % of theelectricity consumption within theindustry. During the pre-study phaseelectrical drives with pump applicationswere identified as large energy users.Because of this a case study at one ofSiemens customers, Stora Enso Fors wasperformed. The system that was evaluatedduring the case study was a throttledsystem with a centrifugal pump forpumping pulp.The results yielded that a saving ofover 50 % could be achieved by replacingthe throttle valve with a variable speeddrive, a frequency converter. Thepayback period was two years and twomonths and the present value for thetotal life cycle cost of the variablespeed system was 662.566 SEK lower thanfor the throttled system. As aconsequence, Stora Enso Fors is advisedto invest in a frequency converter forregulation of the system.The general conclusion is that a focuson system efficiency is the mostimportant factor in energy efficiencyprojects and that the system regulationmethod has a large impact on the overallsystem losses and hence its efficiency.Energy efficiency potential forthrottled systems with centrifugal pumpsis large and significant economicalsavings can be made through investmentswith short payback time..
Rösten : En ljudanalys av rösten i ljudböcker och vad den bär med sig
Undersökningen tar upp hur rösten används, närmare bestämt berättarröstens påverkan, när den tjänstgör som berättarverktyg för läsupplevelsen. Språket är inte bara förknippat med det mänskliga intellektet utan också med den mänskliga kroppen. Språket är bundet till kroppen via vår röst. Vi har analyserat röster från ljudböcker och har använt oss av en lyssningsmodell för att byta fokus var vi lyssnade. Rösten i ljudboken bär med sig orden från författaren men även en del av sig själv.