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235 Uppsatser om Resonance Circuit - Sida 16 av 16
Förnyelsebar plast från rapshalm
Efterfrågan på förnyelsebara och miljövänliga produkter har ökat under de senaste åren. Biobaserade plaster anses vara en av de mest lovande innovationer. Det övergripande målet med examensarbetet var att undersöka möjligheterna att utvinna xylan och glukomannan ur rapshalm. Metoden som utnyttjades var en hydrotermisk extraktion. Inverkan av temperatur, pH och tid studerades genom att tillämpa ett faktorförsök på två nivåer.
Fosterdiagnostik vid MR-undersökningar - gravida kvinnors upplevleser och magnetkamerans påverkan på fostret.
Introduktion: Fosterdiagnostik med magnetkamerateknik (MR-teknik) har utvecklats mycket den senaste tiden och använts som en kompletterande metod till ultraljudsundersökning. Magnetkamera ger ingen joniserande strålning till patienterna, samt ger en mycket mer detaljerad bildinformation än vad andra metoder gör. I samband med MR kan de gravida kvinnorna uppleva olika psykiska påfrestningar genom både själva MR-undersökningen och oro för barnets hälsa. Även om MR-fosterdiagnostiken anses vara en säker undersökningsmetod för fostret föreligger det ändå en ovisshet angående de effekter som kan förekomma. Syfte: Syftet med examensarbetet är att genom publicerad forskning få kunskap som kan utveckla röntgensjuksköterskans möjlighet att ge optimalt stöd och information till gravida kvinnor vid fosterdiagnostik med MR-teknik utifrån följande aspekter: 1.
Utvärdering av VAV i nybyggt kontorshus
VAV (Variable Air Volume) system has been studied in a newly constructed office-building. The goal for the study has been to evaluate how the ventilations system work in practice, if adjustments can be made to achieve an more energy efficient system and to evaluate if other alternative ventilation systems is to be preferred in the further.The degree project has been executed at Helenius Engineering Firm who is working with the environment, media systems, HVAC and energy in buildings. The building that has been studied is owned and operated by Akademiska hus.Literature studies, visits at site, inventory, review of system documentation, energy analyses, interviews, key figures, LCC, sand energy- and indoor climate simulations has been made to study the building. Where appropriate some tools from Six Sigma have also been used.How to achieve an energy efficient system and a pleasant indoor climate is studied with human health and well-being as base for the indoor climate requirements. Technical support systems such as ventilation systems have to be designed so that an acceptable indoor climate can be achieved.
Introduktion av Open Source som arbetssätt
In early January 2010 the authors participated in a meeting with the chief engineer for a company in which a central part is manufacturing of printed circuit boards (PCB). At this meeting it emerged that the machinery and production methods have changed substantially since the early 1990's. The spreadsheet for preliminary production time calculations by the company is today based on conditions from almost 20 years ago. The company has over the years been trying to adjust the spreadsheet template. The result of these adjustments has filled it with historical residue, something which makes the template difficult and time consuming when the primary user tries to handle it.The purpose of this study was to help the company increase its accuracy in the representation of the production times for the different PCB-based products by developing a new costing model based on an already existing but inadequate spreadsheet template. The company also expressed the wish that the new costing model would be less time consuming to work with.The methods used to achieve the goal are interviewing, participatory observations and meetings with relevant persons. The data obtained were analyzed using the theory on PCB production and visualization of data.
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.
Beräkningsmodul för ett förbättrat offertförfarande och minskad icke-värdeskapande tid
In early January 2010 the authors participated in a meeting with the chief engineer for a company in which a central part is manufacturing of printed circuit boards (PCB). At this meeting it emerged that the machinery and production methods have changed substantially since the early 1990's. The spreadsheet for preliminary production time calculations by the company is today based on conditions from almost 20 years ago. The company has over the years been trying to adjust the spreadsheet template. The result of these adjustments has filled it with historical residue, something which makes the template difficult and time consuming when the primary user tries to handle it.The purpose of this study was to help the company increase its accuracy in the representation of the production times for the different PCB-based products by developing a new costing model based on an already existing but inadequate spreadsheet template. The company also expressed the wish that the new costing model would be less time consuming to work with.The methods used to achieve the goal are interviewing, participatory observations and meetings with relevant persons. The data obtained were analyzed using the theory on PCB production and visualization of data.
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.
Integration genom fysisk planering : Ungdomars inflytande i byggprocessen
We live in a time where the influence of citizens is taking a larger role in the spatial planning. The Swedish laws, such as PBL, deals with matters of citizen participation which advocates that the youth should be included in the consultation circuit, but there is no directive given. The report's purpose is to demonstrate methods for how to get the young people's influence included in the spatial planning, with a main focus on the ages between 13 and 21. On the base of literature and two case studies, the goal is to illustrate how to integrate young people through a meeting place in Jonkoping, Sweden. The report is structured along with an analysis based on the literature, two case studies from previous projects and discussions/interviews with young people from four selected areas in Jonkoping. The case studies from Malmo and Gothenburg show how the cooperation between different participants can be organized during the planning and how to give the users a greater involvement. Based on literature and case studies, we carried out a field analysis of the four most segregated areas of Jonkoping; Osterangen, Oxnehaga, Ekhagen and Raslatt.
Effekten av ett probiotikum i en besättning med hög incidens spädgrisdiarré
Magnetic resonance imaging (MRI) has the potential to be used for the diagnosis and study of osteoarthrosis in the equine tarsal region. In the development of new diagnostic MRI techniques cadaver specimens are often used. To allow the use of cadaver legs for these types of studies it is important to know the effect of time after death on the MRI image. Since the relaxation times are temperature dependent, it is interesting to examine whether the time after death and the temperature of the cadaver may play a role in the image appearance and quality. The radio pulse sequences that show the different types of tissues are also important to know when pathological evaluation with MRI is used.
OCT (Optical Coherense Tomography): Teknik och tillämpning
Före år 1895 kunde läkarna endast ställa en sannolik diagnos utifrån vad patienten kunde berätta och om det syntes någon förändring på utsidan av kroppen. Med röntgen blev det möjligt att se insidan av patienten utan att först skära upp densamma, man kan säga att säga att röntgen blev startskottet för diagnostisk avbildning.Vidareutvecklingen av röntgen gav CT (Computed Tomography) där röntgenrör och detektorer roterar runt patienten samtidigt som patientbordet förflyttas. Förutom CT utvecklades även MRI (Magnetic Resonance Imaging), PET (Positron Emission Tomography) och Ultraljud. Gemensamt för alla dessa olika metoder är att det produceras 3D-bilder.1990 kom en helt ny metod för diagnostisk avbildning, OCT (Optical Coherence Tomography), genom att mäta fasförskjutningen och intensitet av reflekterande ljus, ger det i realtid och oförstörande mätning (in vivo) en upplösning på 1 till 15 µm, mycket högre än alla andra vanliga bildåtergivningstekniker. OCT-maskinen kan jämföras med ultraljud, som använder reflektion av ljudvågor för tolkning [1].De första OCT-maskinerna var av typ TD (Time Domain), dessa hade låg upplösning och låg skanningshastighet.