Sökresultat:
1668 Uppsatser om Automatic snow depth measurements - Sida 21 av 112
Att lösa reglertekniska problem med Modelica
The purpose of this thesis is to examine and present the oportunities of solvingcontrol problems using Modelica. This is done by creating some demonstrationexamples with exercises. These examples should cover as many types of controlproblems as possible. The exercises are aimed for people with basic knowledgein modeling and automatic control engineering but with little or no knowledgein Modelica. There are different types of Modelica implementations and the onesused in this thesis are OpenModelica and MathModelica..
Är det möjligt att förutsäga utfall av cochleaimplantation hos barn med auditiv neuropati spektrumstörning? ? En litteraturstudie
Auditory Neuropathy Spectrum Disorder (ANSD) is a collective term for a specific form of hearing loss within a heterogeneous population of patients with mutual audiological test-profile. Cochlear implantation in children with ANSD has been found to result in good outcomes. Previous research, however, has shown the existence of a subgroup of children with ANSD who do not benefit from cochlear implantation but instead are in need of alternative methods of communication. The aim of this literature review was to examine the possibilities to predict outcomes of cochlear implantation in children with ANSD by pre-, intra- or postoperative examinations/measurements and thereby evaluate in which cases cochlear implantation is an appropriate intervention within this group of patients. The material consisted of 10 scientific papers published between 2007-2014.
Vägar och markanspråk inom vindkraftsparker i Västerbottens län : Hur verkliga mått förhåller sig till vad som uppges i miljökonsekvensbeskrivningar
The purpose of this study was to increase the level of knowledge in the field of Environmental Impact Assessment (EIA) for wind power. The study includes six wind power farms in the County of Västerbotten in northern Sweden. The main questions were: What are the real dimensions of roadways and land claims for both roads and wind power turbines? How do those dimensions correlate with the dimensions stated in the EIA? Are there any differences in values of the dimensions between the wind power farms that are included in this study? The width of the roadways and the land claims for both roads and wind turbines in wind power farms were examined on site. The results from the examinations were compared with the dimensions available in the EIA for each wind power farm.
Järnets förekomst i grundvattnet i isälvsavlagringar i Dalarna : Bakgrundshalter och rörmaterialets inverkan vid grundvattenprovtagning
A study has been performed that investigates the variation of iron content in groundwater.The study was initiated by Midvatten AB, which noticed that the iron content in groundwater samples can vary greatly over small distances. The purpose of this study was to geochemically and geohydrologically determine the factors that influence the content of iron and manganese in groundwater from a selection of eskers in Dalarna, and determine how to best sample groundwater with the method used by Midvatten AB. An evaluation was made of how the vertical variation in soil material, water composition, pumping time and pipe material affects the content of iron in groundwater. Piper diagrams were used to study the relationship between the chemical composition of the groundwater and the content of iron and manganese in groundwater samples from the studied areas. The groundwater from the studied areas was then classified in the Piper diagrams, according to the content of the major ions.
Enstudie om lågtempererat värmesystem i vägg : -Fokus på inomhusklimatet och energianvändning
Today the human being see energy as a matter of course but the resources that is used for extract energy is today not enough for the world demand. Of all the energy that is used in Sweden today approximately 40 % goes to the building stock. This number will most likely increase if not necessary actions will be made on the already existing building stock since new houses constantly are built which will be added up on the already existing energy supply. This takes cause of action on the already existing building stocks, to fulfill the demands of the future use of energy that has been set by the authority. At the same time the thermal conditions cannot be influenced by the necessary changes that must be made.
Returhantering vid LensLogistics AB: en process- och
flödesutredning för förbättringar
Return handling is often regarded as a slow and complex process. Studies have shown that it is not unusual for a return to cost up to nine times as much as a standard outbound delivery. An efficient return handling process is therefore essential to all competitive companies dealing with logistics. This report investigates, analyzes and gives suggestions on development with the purpose to improve the return handling process at LensLogistics AB in Kista, north of Stockholm, Sweden. The study has been conducted from a deliberately practical point of view in order to suggest improvement suggestions possible to implement and thereby change the entire return handling process.
A Swedish national forest programme ? participation and international agreements
Sweden is in the initial phase of forming a national forest programme (nfp). The establishment of an nfp has been evoked by international policy developments and a national debate questioning Swedish forestry and forest policy. National forest programmes are participatory processes for the development and implementation of forest-related policies and international commitments. Hence, the aim of this master thesis is to assess the stakeholders? acceptance of participation and integration of international issues within the Swedish national forest programme.
Betydelsen av multimodal rehabilitering för nedstämdhet, oro och fysiska begränsningar hos patienter med långvarig smärta
The aim of this study was to compare perceived disability in daily activities, anxiety and depression for patients with chronic pain (>3 month), before and after rehabilitation. Another aim was to examine if there were any correlations between disability in daily activities and the extent of anxiety and depression before and after rehabilitation.For the measurements, Disability Rating Index (DRI) that measures disability in daily activities, and Hospital Anxiety and Depression Scale (HADS) ) which measures the extent of anxiety and depression were used. The study was carried out with 50 patients who had suffered from chronic pain and with the objective to return to work after rehabilitation. Of these, 90 % were female. The measurements were carried out at three measure points; before rehabilitation, seven weeks after rehabilitation and one year after rehabilitation.The main result did not show any statistically significant improvement in ability to perform daily activities.The only significant difference that emerged was an improvement in anxiety seven weeks after rehabilitation compared with before.
Personbilar i singelolyckor med dödlig utgång på Sveriges vägnät : Orsaker till olyckor och rekommendationer om hur dessa kan förebyggas
In Sweden the most common type of road traffic accidents involving passenger cars are single accidents (where only one vehicle is involved). The aim of this thesis is to analyse how these accidents occur, and present recommendations on how to reduce the number of deaths. Data has been collected from the Swedish Transport Administration?s in-depth studies of fatal accidents. Road traffic accidents with fatal outcome that happened on public roads during the years 2007 to 2009 have been studied.
Analys av massapumps- och mixerarbete vid Metsä Board Sverige AB, Husums Fabriker : Energibesparingsåtgärder vid blekeri 4 & 5 med jämförelse mot ny utrustning
Husums plant has a selection of different pulp pumps at bleaching plant 4 and 5. The displacement- (HC-pump, Sund Defibrator PTD-60) and centrifugalpumps (MC-pump, MCA 42-200, MCP 30/20) are of interest in this report. The centrifugal pumps are controlled by throttle valves, which result in an energy loss. Chemical mixers are used to mix ClO2 into the pulp before proceeding into a holding tower where the bleaching process occurs.The energy demand of the different positions has been measured or calculated to be used in comparisons against new equipment. Quotations were requested and delivered from Valmet and Sulzer.
Alternativ till fortsatt elektrisk generering i Olidan
In this thesis a possible cost effective runner change of some of the units in the hydroelectric power station Olidan is investigated. The possibility to drive a unit at the same efficiency point through a change of the turbine shaft speed and the rate of discharge is tested. Furthermore the theories behind model testing, determination of efficiency increase from model to prototype and efficiency measurements shall be discussed and analyzed with Olidan as a starting point.A predicted curve has been built on information from model tests and field measurements on the existing runners and runner data from the test of the new model. The predicted curve shows the difference in efficiency between an existing runner and a modern one. It is the difference in efficiency that is used in the calculations that are to show whether changing to a pair of new runners will be cost effective or not.
Hedgefonder : Hur kan dess risker och möjligheter förmedlas
We have in this essay studied the Swedish Hedge Fund Market available for the average Swedish private investor. We have closely looked at the risk measurements that are applicable on the evaluation of Hedge Funds today, and furthermore studied how they are communicated and what they actually contribute with in terms of risk and yield. Our survey attempts to clarify the shortcomings in the communication between the Hedge Fund Managers and their smaller investors. Do they really know where they put their money? The market is rapidly expanding and our goal was to find improved ways to inform about the Hedge Funds risks and opportunities.
En simuleringsmiljö för distribuerad navigering
This master thesis studies distributed navigation which isa function implemented in a future network based combat information system to improve the accuracy in navigation for combat vehicles in a mechanized battalion, above all in the event of loss of GPS. In the event of loss of the GPS the vehicles obtain dead reckoning performance through the backup system that consists of an odometer and a magnetic compass. Dead reckoning means a drift in the position that makes the accuracy in the navigation worse. The distributed navigation function uses position and navigation data with measurements between the vehicles to estimate the errors and uncertainties in positions, which are used to improve the accuracy in position for the vehicles. To investigate and demonstrate distributed navigation, a simulation environment has been produced in Matlab.
Produktionsskillnader och virkesskador med olika typer av matarvalsar :
Earlier investigations showed that damages on timber from feeding rolls could be within the lower classes of damage according to VMRs classes. Knowledge about differences in productivity between kind types and aggressive types of feeding rolls is necessary because it should influence the question about damages on timber caused by different feeding rolls.
In this study the production and timber damage in a harvesting head were evaluated at three levels of pressure (8, 10 and 14 MPa) on the feeding rolls, and with three different types of rolls. One type, the rubber cushioned steel plate roller had 10 mm studs and rubber damping, one ?middle? type made of solid steel with 14 mm studs, and one aggressive type, also made of solid steel with 18 mm studs.
Inställning av automatikermed spänningsreglerande verkani det sydsvenska 400-130 kV nätet
The voltage level in the power grid varies due to variations in load and production. Normally these variations are manageable, but they may be excessively large during a disturbance. If the voltage is too high it may damage the equipment in the grid and too low voltages may cause problems like voltage instability. The magnitude of the voltage variation depends on the short circuit power capacity of the point of interest.This problem may become lore prominent due to automatic voltage regulation that acts on shunt reactors and shunt capacitors. When the shunt reactor is connected or disconnected to the grid it may cause such large changes in the voltage that the shunt reactor starts hunting.