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370 Uppsatser om Voltage drop - Sida 2 av 25
Faktorer som kan förhindra avhopp från gruppträffar vid behandling av övervikt och fetma
To complete an overweight treatment program is associated with better weight loss. Previous studies have in principle focused on drop-out from the entire program, not individual parts of a program. Factors previously shown to influence the patients´ weight loss results are: frequency of individual meetings with a professional, the lack of social support from family or friends, the lack of motivation and in a few studies vacations. In several studies the drop-out patients have stated that their reasons for drop-out were dissatisfaction with the staff and the program design. Drop-out has also been shown to be connected with difficulties in adherence to the diet.
Värdering och jämförelse av kvalitetsfaktorer för lokal kollektivtrafik i Helsingfors och Göteborg
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Mineralogisk och strukturell inverkan på fragmenteringsenergi och andel producerat finmaterial i en konkross
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
En analys av nuvarande och framtida trygghetsarbete i fastighetsbolag "trygghet och säkerhet en investering för framtiden"
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Mat, måltider och maskuliniteter
To complete an overweight treatment program is associated with better weight loss. Previous studies have in principle focused on drop-out from the entire program, not individual parts of a program. Factors previously shown to influence the patients´ weight loss results are: frequency of individual meetings with a professional, the lack of social support from family or friends, the lack of motivation and in a few studies vacations. In several studies the drop-out patients have stated that their reasons for drop-out were dissatisfaction with the staff and the program design. Drop-out has also been shown to be connected with difficulties in adherence to the diet.
Hälsoinformation och kostråd via webbplats och mobilapplikation : Kvinnor och män under 50 år vill ha tillgång till hälsoinformation och kostråd genom sin mobiltelefon
To complete an overweight treatment program is associated with better weight loss. Previous studies have in principle focused on drop-out from the entire program, not individual parts of a program. Factors previously shown to influence the patients´ weight loss results are: frequency of individual meetings with a professional, the lack of social support from family or friends, the lack of motivation and in a few studies vacations. In several studies the drop-out patients have stated that their reasons for drop-out were dissatisfaction with the staff and the program design. Drop-out has also been shown to be connected with difficulties in adherence to the diet.
Identifiering av saneringmetoder med översiktlig bakgrunds- information - En studie av förorenad industrimark på fastigheten Elektro 6 i Gullspång kommun
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Lågoffsetkomparator
Detecting small signals with a comparator demands that the total voltage offset is lower than the actual signal. The total offset includes the voltage offset in the comparator and the voltage offset that is created by the offset currents that flows thru the load at the comparators input. The goal with this comparator that has been developed has been that it will have a total voltage offset at maximum 500 uV. The comparator does not need to be extremely fast or does not need to operate in a big frequency area. To have all the flexibility that is needed a full custom technique is used.
LAN-Uppgradering
The interest in small-scale electricity in Sweden has increased strongly in recent years. The interest is noticeable both among politicians to increase the share of renewables in the energy mix, and among electricity consumers to partially replace purchased electricity with self-produced. This has resulted in a significant increase of electricity production in low voltage grids in recent years, and the trend appears to continue in the coming years. The majority of the new production plants are solar cells, followed by wind turbines, and it is also in these the greatest efforts are made in this paper.Distributed generation is often seen as something positive since it will contribute to reduced transmission losses and reduced Voltage drop in the networks, and that it increases the share of electricity from renewable sources. In cases where the grids are not strong enough, or in other ways not adapted to manage the installed production, power quality may be adversely affected.
Hjälpkraftsystem med två lågspänningsnivåer
Because of increasing demand of power on Malmbanan the capacity of the existing wires which supply the trains must be increased. This increases the stress on the existing poles and for this reason the system for supplying the loads along the railway is to be removed from the poles and be replaced by some other system. This thesis is a study on a two-level low voltage (1 kV and 0.4 kV) electrical system with the aim to investigate if it can be an alternative to the system used today taking into account the voltages, fault currents and costs.In this thesis the following tasks have been performed:? Gathering of data? Description of basic theory? Loadow and fault current calculations of the system with MATLAB? Life Cycle Cost estimate of the system? Analysis and conclusions from the resultsThe results show that the new system can be an alternative to replace today's system. The simulations and calculations show that the Voltage drop is at an acceptable level and that the fault currents are large enough to supply a safe disconnection if a fault occurs at the far end of the system..
Det är värre att inte börja studera än att hoppa av : En fenomenologisk studie om hur icke traditionella studenter upplever studieavhopp från högskoleutbildning
In Sweden we have the highest rate of nontraditional students among Europe. Coincidently, we also have the highest rates of drop outs among OECD. In this particular field, drop out from higher education, there is a need fore more qualitative studies that can support the "statistics". Studies about experiences of drop outs are significant for society, university and individual. The aim of this study is to describe and understand how nontraditional student experiences drop out from higher education.
Det är värre att inte börja studera än att hoppa av: En fenomenologisk studie om hur icke traditionella studenter upplever studieavhopp från högskoleutbildning
In Sweden we have the highest rate of nontraditional students among Europe. Coincidently, we also have the highest rates of drop outs among OECD. In this particular field, drop out from higher education, there is a need fore more qualitative studies that can support the "statistics". Studies about experiences of drop outs are significant for society, university and individual. The aim of this study is to describe and understand how nontraditional student experiences drop out from higher education.
Hantering av småskalig elproduktion : Utveckling av modell för dokumentation och elkvalitetsberäkningar
The interest in small-scale electricity in Sweden has increased strongly in recent years. The interest is noticeable both among politicians to increase the share of renewables in the energy mix, and among electricity consumers to partially replace purchased electricity with self-produced. This has resulted in a significant increase of electricity production in low voltage grids in recent years, and the trend appears to continue in the coming years. The majority of the new production plants are solar cells, followed by wind turbines, and it is also in these the greatest efforts are made in this paper.Distributed generation is often seen as something positive since it will contribute to reduced transmission losses and reduced Voltage drop in the networks, and that it increases the share of electricity from renewable sources. In cases where the grids are not strong enough, or in other ways not adapted to manage the installed production, power quality may be adversely affected.
Undersökning av elkvalitet i distributionsnät med omfattande vindkraftselproduktion
The goal for this master thesis project has been to investigate the power quality in adistribution grid, which has a high fraction of dispersed power production due towindmills. The study has been done on a grid in Laholm South of Halmstad, whereapproximately 45 windmills are connected to the distribution grid owned by SHKEnergi. The investigation has been focused on to two radialy fed 20 kV lines, wheretwelve windmills are connected.Voltage variations have been studied by creating a model of the grid in the simulationprogram SIMPOW. The largest deviation that has been found in any point of the gridis ±1.9 % of the nominal voltage. This deviation is a result of varying powergeneration from the windmills and the voltage regulation at the connection point ofthe line.
Ny princip för spänningsreglering i Fortum Distributions mellanspänningsnät i Stockholm.
The voltage regulation in Fortum Distributions medium voltage network in Stockholm does not work satisfactory. This results in too high distribution voltages with many customer complaints as a consequence. The reason is the model responsible for compensating for Voltage drops in the distribution network. Despite several adjustments Fortum has not been able to find the source of the high voltages and has therefore appointed an investigation in the form of a thesis work.The aim of this investigation is to locate the error and to produce a proposal regarding the solution of this error using the existing system, common industrial knowledge, state of the art research and the option to use voltage readings from the different substations.The conclusion of this master thesis is that the largest contribution to the high voltage levels is made by the large compensation for distribution loses. Furthermore an additional error in the model has been found.