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787 Uppsatser om Measurements - Sida 31 av 53
Konstruktion av Industriellt Vibrationsmätningssystem med signalbehandling baserad på Digitala Vågfilter av Lattice-struktur
In this bachelor thesis a complete prototype of an industrial vibration measurement platform has been developed. By measuring a number of variables such as acceleration, temperature and speed conclusions can be drawn on machinery health. The aim is to evaluate hardware and software solutions for a possible future product. Based on a requirement specification a proper hardware design has be developed. The hardware consists of a four-layer PCB with an ARM Cortex-M3 microcontroller and about 250 other components. The PCB was designed, assembled, tested and finally housed in a box.
Generationsskräpsamling med explicit kontroll av hårdvarucache
This report evaluates whether an interpreted high-level garbage collected language has enough information about its memory behaviour to make better cache decisions than modern general CPU hardware.With a generational garbage collector, depending on promotion algorithm and generation size, around 90% of all objects never leave the first generation. This report is based on the hypothesis that, because of the low promotion rate, accesses to higher generations are sufficiently rare not to benefit from caching.To test this hypothesis, we built an operating system with a Scheme interpreter in kernel mode, where the interpreter controls the cache. Generic x86 PC hardware was used, since it allows fine-grained control of cache decisions.Measurements of execution time in this interpreter show that disabling the cache for generations higher than the first does not give any performance gain, but rather a performance loss of up to 50%.We conclude that this interpreter design is not an improvement, but cannot conclude that the hypothesis is false in general. We suggest building a better CPU simulator to gather more data from which to make better caching decisions, moving internal interpreter data structures into the garbage collected heap and modifying the hardware to allow control in the currently rigid dimension of where data is cached---for example separate control of instruction and data caches and separate data caches for different areas of memory..
Utredning av fastighetsel i ett äldre och ett ombyggt flerbostadshus i Gävle
The residential and service sector in Sweden accounts for approximately 38% of the total energy usage and Sweden has an aim to reduce the total energy use by 20% by 2020 compared to 2008, which means residential sector will have to improve energy efficiency. As part of that a law was instituted by the Swedish parliament that all properties must have an Energy Performance Certificate (EPC) to thereby give the property owners a greater insight into energy use in their buildings and propose recommendations for energy-efficiency measures. On the EPC, a value on the building's energy performance in terms of energy use in kWh / m2 per year is declared, of which electricity is a share of it. Instructions on what to include in the amount facility electricity for running the facilities is regulated by the authority for building, Boverket while SVEBY has made an interpretation of the regulations in their report "Brukarindata bostäder" where they have a table on what should be included in the amount and what not to include.This report is a study of two similar apartment buildings, where one of the buildings recently underwent renovation, to see if the declared amount of energy for electricity, in the EPC, is consistent with the measured value, and whether there has been any reduction in facility electricity in the renovated building after the renovation.The result shows that the measured value of the building electricity was 2.6 kWh / m2 per year, 28,8 %, lower than the declared value in the building that have not undergone a renovation. Calculation of values from previous years (2011) by the same percentage of facility electricity as in the results of the Measurements, 56.7%, it becomes clear that the declared value for facility electricity in the EPC of the renovated building do not correspond with reality and that there has been an increase in use of facility electricity after the renovation..
Design och framtagande av mätanordning för ström och effek på trefas ledare : Josi Periferi strömmeter
The assignment is issued by Scania Maintence AB seeking a new approach to detect power changes in their industrial processes. The work has taken place at Ångströmslaboratoriet and tests have been performed at Scania AB Södertälje.Today?s society consumes enormous amount of energy. In both economically and environmental view, it is important that the processes are effective, with high power factor. There are many ways to measure power in the industry, what they all have in common is that the installation is advanced, requires time and planning.
Milk production in dairy cows and goats : a case study in the Nyando district inSouth-Western Kenya
Water is an essential factor for both people and animals, and access to water is therefore of great importance. The water access also largely determines the availability of food for people and feed for animals. The aim of this study was to survey the affect of water access on milk production from dairy animals. The study included nineteen farm visits that were made in the Nyando district in Kenya between February and Mars 2011. Farm visits included interviews with questions about for example number of dairy animals, milk production, water access, feed and water routines.
Jämförelse av beräknad och verklig grundvattensänkning vid vägportar
Present master of science thesis has been carried out at the Swedish Road Administration consulting services (Vägverket Konsult) in Karlstad. The purpose of the study is to investigate how well the calculated drawdown of the groundwater table predicts the actual drawdown when the road and railway gates at the studied sites are built. For this purpose the groundwater levels at the three bridges were measured during 6 months. The bridges in question are two railway bridges situated in Ölme and Ulvåker and one road bridge crossing a pedestrian and cycling path in Lidköping.In Ölme the calculated area of influence was smaller than the measured one. It differed up to 30 meters, i.e.
Optimering av driftläggningar i Fortums nät
Future emission legislation puts great emphasis on increasing the efficiency of the engine, thereby reducing fuel consumption. The tribological contact between cylinder liner and piston ring is where an great amount of energy is lost due to friction, and by reducing these losses an reduction in fuel consumption can be achieved.The aim of this thesis was to evaluate the tested piston ring coatings against a plasma sprayed cylinder liner and rank these combinations of materials for friction and wear resistance. The coatings that were tested was Cr + Al2O3, (Al,Cr)N, two types of CrN and WC / C.The experimental tests were performed with a so-called pin-plate, where used oil with addition of an acidic mixture of sulfuric and nitric acid to mimic the acidic condensate formed when exhausts recirculate, were added with a continuous flow. The results were then analyzed by weighing, studies by optical microscopy and scanning electron microscopy (SEM) and profile Measurements.The results from each material combination were that the plasma coated cylinder liner wears too aggressively in order to yield a ranking of the piston ring coatings based on the parameters of friction and wear resistance. It is therefore proposed that an alternative coating on the cylinder liner should be developed, lacking the large abrasive wear on piston rings and that can withstand the corrosive environment resulting in engines equipped with EGR.
Modellering av reserv- och nödkraftsystem i JAS 39 Gripen
Simulation is a vital tool during development of JAS 39 Gripen, since money and time can be saved.The Auxiliary and Emergency Power System, AEPS, is a subsystem of the secondary power system in Gripen. It has the function of providing the aircraft with electrical and hydraulical power before activation and after deactivation of the main engine. The system also functions as backup in case of a safety critical problem in the main power supply system. The system basically consists of a control unit and an auxiliary gearbox. The gearbox is driven by an air turbine.
Energieffektivisering av stenstadshusen - genom byggnadstekniska energisparåtgärder
The purpose of this degree-project was to investigate the possibilities for primary air preheating into the two smallest waste incineration boilers of Halmstad Energy and Environment. The investigation is a pre-study which has the primary goal to evaluate technical and financial offers from companies that manufacture primary air preheater, and investigate if it is technically and financially profitable to do a purchase on primary air preheaters in the future.In the pre-study it is proposed that it is most efficient to have individual primary air preheater, one for each incineration boiler and the primary air are also proposed to be preheated by hot water in the pre-study. Further in the pre-study it is proposed that the heat-exchanger should have plain tubes instead of finned tubes, to avoid getting dirty fast. The space in the boiler-room is limited, and therefore the major problem was to fit in the primary air preheaters into the boiler-room. By comparing the different offers from the companies, the result in the pre-study shows that the offer from the company C.A.
Prövning av måttet Läpp-till-Lyft (L-t-L) på vuxna utan sväljsvårigheter
Context: Lip-to-Lift (L-t-L) is a bedside-method for measuring oral transit time at swallow. It was designed for a swallowing examination of persons on nursing homes where weight loss was noted in people with average L-t-L-time >5 seconds (Sandin, 2005). The measurement was validated and evaluated by Eriksson, Bremer Zerpe (2008).Objectives: The study objective was to examine L-t-L on a group of young adults without swallowing disorders and as to examine the inter- and intra-judgereliability of the measure.Questions:What is the L-t-L-time for young adults without swallowing disorders?Are there any gender differences regarding L-t-L-time?How high is the inter/intra-judge reliability of L-t-L?Method: Examination of L-t-L-time was carried out on 20 young adults, aged 19-27 years, without swallowing disorders after Sandin?s (2005) instructions. Measurements of 20 swallows per person were made.Results: The average L-t-L-time of young adults without deglutition-difficulties was 1.13 seconds (sd =.14).
Fl?ckreducering ? Bl? Vinranka En j?mf?rande studie av tv? efterbehandlingsmetoder vid reng?ring av glaserad keramik
This study explores the effects of two different post-treatment methods on stain reduction in glazed creamware from the late 20th century. The objects stains have been characterized by type one and type two stains which is the result of prolonged contact with food residues, were subjected to the same initial stain reduction. The two post-treatment methods examined are soaking the objects in deionized water and surface rinsing with deionized water. The comparative analysis included photographs under normal and UV-light exposure to assess stain visibility, weight Measurements before and after treatments to monitor the absorption and evaporation of liquids, and observations throughout the experiment. The results revealed that while type two stains showed significant alterations after treatments, specifically after soaking, type one stains remained unaffected by both methods.
Anpassning av passivhus för ett kallare klimat - teknisk och ekonomisk analys
The purpose of this degree-project was to investigate the possibilities for primary air preheating into the two smallest waste incineration boilers of Halmstad Energy and Environment. The investigation is a pre-study which has the primary goal to evaluate technical and financial offers from companies that manufacture primary air preheater, and investigate if it is technically and financially profitable to do a purchase on primary air preheaters in the future.In the pre-study it is proposed that it is most efficient to have individual primary air preheater, one for each incineration boiler and the primary air are also proposed to be preheated by hot water in the pre-study. Further in the pre-study it is proposed that the heat-exchanger should have plain tubes instead of finned tubes, to avoid getting dirty fast. The space in the boiler-room is limited, and therefore the major problem was to fit in the primary air preheaters into the boiler-room. By comparing the different offers from the companies, the result in the pre-study shows that the offer from the company C.A.
Byggnadsfysikaliska riskbedömningar : Metod för tidig hantering av fuktsäkerhetsfrågor
The purpose of this degree-project was to investigate the possibilities for primary air preheating into the two smallest waste incineration boilers of Halmstad Energy and Environment. The investigation is a pre-study which has the primary goal to evaluate technical and financial offers from companies that manufacture primary air preheater, and investigate if it is technically and financially profitable to do a purchase on primary air preheaters in the future.In the pre-study it is proposed that it is most efficient to have individual primary air preheater, one for each incineration boiler and the primary air are also proposed to be preheated by hot water in the pre-study. Further in the pre-study it is proposed that the heat-exchanger should have plain tubes instead of finned tubes, to avoid getting dirty fast. The space in the boiler-room is limited, and therefore the major problem was to fit in the primary air preheaters into the boiler-room. By comparing the different offers from the companies, the result in the pre-study shows that the offer from the company C.A.
Nätmobbning Om relationen mellan traditionell mobbning och nätmobbning i grundskolan
This study investigates the relation between cyberbullying and traditional bullying (in school). In previous research it has been argued that one should separate cyberbullying and traditional bullying both in definitional and Measurements issues. However, in Swedish school, there are no marked differences between the two forms of bullying, teachers are responsible to prevent them both. The research is based on 3925 students in years 3-9 (1950 girls and 1975 boys) in 19 schools in the Gothenburg region and two from the Stockholm region. The students have taken a digital survey at school, regarding both traditional and cyber bullying.
Rationell produktion av platsgjutna stommar för flerbostadshus
The purpose of this degree-project was to investigate the possibilities for primary air preheating into the two smallest waste incineration boilers of Halmstad Energy and Environment. The investigation is a pre-study which has the primary goal to evaluate technical and financial offers from companies that manufacture primary air preheater, and investigate if it is technically and financially profitable to do a purchase on primary air preheaters in the future.In the pre-study it is proposed that it is most efficient to have individual primary air preheater, one for each incineration boiler and the primary air are also proposed to be preheated by hot water in the pre-study. Further in the pre-study it is proposed that the heat-exchanger should have plain tubes instead of finned tubes, to avoid getting dirty fast. The space in the boiler-room is limited, and therefore the major problem was to fit in the primary air preheaters into the boiler-room. By comparing the different offers from the companies, the result in the pre-study shows that the offer from the company C.A.