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1072 Uppsatser om Audio Frequency Track Circuit - Sida 12 av 72
Gruppmålföljning av markobjekt
This Masters Thesis considers tracking of ground targets. Since ground targets often are difficult to detect with sensors a track is easily lost in ground target tracking. The main question in this thesis is whether information on close targets and observations of them can be used to make the tracking more reliable. An algorithm using Kalman filters and JPDA-association to create a group track for vehicles travelling together has been implemented in Matlab. Using the state of the centre of the group the state of a vehicle in the group can be updated.
Peltierelement - spillvärme till el : Peltier element - waste heat into electricity
The purpose of this thesis has been to determine experimentally how good a peltierelement is to convert waste heat from wood burning. Three different peltier elementswere used in a comparison study. The comparison was mainly done to know howmuch power could be obtained from each element. Even, a circuit with a step-upfunction has been created to give a higher output voltage than the peltier elementitself. The result of the experiments was a low output power, the highest valuereached 2.18W.
Mätning av partikelmassa i avgaser från en dieselmotor
This master thesis was a continuation of a previous study in the diesel exhaust characterization, which is part of the academical work embedded in the EMIR-1 project. The main objective of this thesis work was to finish the installation and make the proper modifications of the particulate mass measuring system located in one of the engine test cells at KTH, in order to be able to measure the mass of the particles from the exhaust of diesel engines.This experiment requires a diluted flow sample from the exhaust that should be sent to the device that makes possible the measurement of particle mass, called TEOM. In the first stage of this project, the objective was to study and make the proper modifications in the existing KTH diluter because there were several problems to obtain a constant dilution ratio from it during tests.This modifications were made and it resulted in a great improvement in the maximum inlet and outlet flow that this diluter can handle. Therefore another modification is proposed for controlling the inlet exhaust flow so it will be possible to regulate the dilution ratio and make it constant along a wide range of engine loads and speeds.The second and most important stage was to make particulate mass measurements possible by analyzing the frequency signal from the TEOM device. The idea was to obtain the frequency of oscillation from the tapered element in the TEOM, and therefore with the proper correlations, be able to predict the particulate mass concentration in the exhaust flow from the engine.An electrical problem in the TEOM circuit was detected and corrected, so the signal that carries the frequency from the TEOM can be analyzed properly.
Utveckling och implementering av ett audiopejlsystem baserat på tidsdifferensmätning
The use of spread spectrum signals has increased dramatically in military applications. Finding methods for detecting and positioning of these signals have become interesting research areas for signal intelligence purposes. One method is to measure the time difference of arrival (TDOA) that occurs when two receivers are synchronous and spatially separated. Based on the TDOA-technique an audio-demonstrator has been developed and implemented. This report describes the theory for how sound received in microphones can be used to extract information about the transmitter?s position from the measured time difference.
Utvärdering av patientens postoperativa smärta, illamående och informationsbehov efter införandet av en ny dagkirurgisk modell
Introduktion: Fler och fler opereras inom den dagkirurgiska verksamheten i Sverige. Fo?r att bevara patientsa?kerheten och kvaliteten i va?rden, bo?r den sta?ndigt utva?rderas och vid behov fo?rba?ttras. Alternativ i detta fo?rba?ttringsarbete kan vara anva?ndandet av olika dagkirurgiska fast-track modeller, da?r den perioperativa omva?rdnaden, medicineringen och anestesimetoden anpassas efter individen och det kirurgiska ingreppet.
Ström- och temperaturkontroll
Storing kinetic energy in a flywheel allows for more efficient driving of electricvehicles. Research in this area is in progress at Uppsala University, where a flywheelwith magnetic bearings encased in a vacuum chamber is being constructed. To makethis possible methods for measuring the current through the electromagnets in thebearings and temperatures in the flywheel need to be developed. This has been thepurpose of this report. The current measurement resulted in a resistive method, andthe implementation of eight measurement circuits in the system.
Turbinkretspump system - Kraftvärmeverket i Borås
The Rya power plant in Borås produces district heating, district cooling and electricity. The plant is owned by Borås Energi och Miljö AB and is run by Dalkia Facility Management AB.In order to get the best heat exchange from the district hot water a pair of twin pumps and a turbine circuit pump are used as return pumps. Turbine circuit pumps are used to increase the pressure through the heat exchangers at the power plant. The pumps are in use when the flow is over 2 000 m3 h-1 and during the summer when re-cooling is used to improve the effectivens of the heat boilers.Since the pumps, that are parallel connected, rotating at a fixed rate per minute, the pressure is regulated with regulating valves. This report shows that during the 4,300 hours that the pumps where in use, energy corresponding to 590 MWh was wasted.
Ordfrekvens och ordinlärning: En analys av läromedlet Caminando för spanska steg 1 och 2
It is important that the language in textbooks for foreign language learners reflects the language that the learners would encounter in real life. For this reason, the presence of the thousand most common nouns in two Swedish textbooks in Spanish for upper secondary school is observed in this study. Furthermore, this study aims to examine how these nouns occur in order to determine if their pattern of occurence favours the learning and consolidation of words. The main materials that have been used are A Frequency Dictionary of Spanish by Davies (2006) and the word search program available in the digital versions of the textbooks. The results show that the presence of the thousand most common Spanish nouns does reflect the frequency information presented in the frequency dictionary but not all thousand nouns are included.
Utva?rdering av mikrofoner fo?r ho?rselhja?lpmedel
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.
Effektivisering av produktionsflöde : Införande av ny teststrategi
Ericsson AB in Katrineholm is a part of the Section Business Unit Network in the Ericsson Group. The plant's main task is to produce printed circuit boards in small volumes with a high product mix and focus on delivery and cost effectiveness. At the factory they produce printed circuit boards in the Module department.The Module department has for a long time had a high output of non-approved circuit boards in their production. This has led to a growing stock of non-approved circuit boards on the company?s repair department.The purpose of this thesis is to investigate how Ericsson in Katrineholm can increase the outflow of approved articles in their test process in the Module department.
Rotationsdämpare med integrerad fjäder
This final thesis is carried out at BAE Systems Hägglunds in Örnsköldsvik. The mission was to construct and integrate a new semi-active damping unit in the terrain vehicle BvS10. Questions that came up during the process, among others, was how to mount the damping unit to the vehicle in a flexible way without exposing it to unnecessary wears.A generation of the concept is made in 3D using CATIA V5 of a possible solution to the problem. The idea is to weld the unit to the skid girder which is one of the main constructions of the track system. In this way the damping unit will come closer to the track system, which will partly protect it from impacts from below and minimize current problems with breaking forces in the torsion shafts.The complete construction was then analyzed, first by theoretical calculations and then with the FEM-tools in CATIA V5.
Taggade bibliotek ? en studie av adoptionen av RFID på svenska folkbibliotek
The purpose of our research was to examine whether the acceptance and diffusion of RFID technology among the employees at public libraries in Sweden, follow the classic diffusion of innovation model. RFID or Radio Frequency Identification, is a technology that uses radio frequency and microchip technology to track items, in our case, library books and other library materials. Diffusion is the process by which, in our case, the RFID technology is adopted by the library staff. The purpose of this study was to examine what factors influenced the acceptance and adoption of RFID among the library staff. We used Everett Rogers' Diffusion of innovation theory as our framework.
Fördelning av resultat på den svenska börsen
This paper replicates a test performed by Burgstahler and Dichev (1997), which identifies a kink in the frequency distribution of earnings for companies listed on American stock exchanges. Their claim, that the kink is evidence of earnings management, has however been dismissed as a methodical consequence. To address this concern, this paper not only replicates the test in general, but also performs tests on a split sample, where founding family-owned companies are separated from the others, since earlier research has shown that founding family ownership is correlated with less earnings management. The results are in line with the findings of Burgstahler and Dichev, with a significant kink in the frequency distribution in the general test. The findings also show that the significance of the kink increases in the non-family-owned sample, while it disappears in the family-owned sample.
EAS-tagg med fuktsensor : Design och utvärdering av EAS-alarmteknologi för fuktdetektering
Electronic article surveillance (EAS) is widely used in shops and libraries together with an RF-tag attached to the goods or books in order to prevent shoplifting. By implementing the addition of a moisture sensor to the RF-tag, other functions become possible, including the ability to use as an alarm with regards to frozen goods, which have been shipped but which have melted and have, subsequently, refrozen. In- relation to care for the elderly, one time-consuming step involves checking whether there is the necessity for a change of diaper and this can, instead, be based on an RF-tag with an EAS-system alarm. A preliminary investigation was made using the moisture sensors, which involved how the resistance changes when liquid and/or heat is applied. A simulation of the LCCR circuit (RF-tag with the sensor) was conducted in order to determine how the resonance frequency changes for different resistances levels.
Digital videoregistrering
This Bachelor thesis examines the possibility of replacing an outdated, analog video recording system to a digital counterpart. It is key that the video and audio signals remain synchronized, generator locked and time stamped. It is up to nine different video sources and a number of audio sources to be recorded and treated in such a manner which enables synchronized playback. The different video sources do not always follow a universal standard, and differ from format as well as resolution. This thesis aims to compare a number of state of the art commercial of the shelf solutions with proprietary hardware.