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4841 Uppsatser om Water model - Sida 11 av 323
Driftoptimering av torkmaskin : Driftoptimering av torkmaskin 3 vid Billerudkorsnäs Karlsborg AB
The company Olofsfors AB manufactures drive belts for forest machinery, known as ECO-Tracks, and abrasion-resistant steel and cutting edges for graders, excavators and tractors, known as Bruxite and SharqEdges. Manufacturing these products requires the steel to be heated and molded, then submerged in water and hardened. The water used in the hardening of steel is pumped to the process from pits below the floor and then pumped back to the pit after it?s been used. Since the temperature of this water rises after being used to harden the steel the temperature of the pumping pit needs to be adjusted to maintain its setpoint of 21°C.
Modell av en synkronmaskin för PSCAD/EMTDC med magnetisk mättning i d-led och elektriskt gränssnitt för fältmatare
This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.
Analys, modellering och återskapande av fordonsdynamiska rörelser i tåg
The purpose of this thesis was to analyse, model and finally generate dynamic vehicular motions in a train. The objective with the analysis was to find important motions for a realistic train experience. The motions from the analysis were then weighted against possibilities for generation in a motion platform.A dynamic motion model was created to model the selected motions. The model was implemented in a simulation environment, more specifically MATLAB/Simulink. The simulation environment was used to simulate the model and to generate outputs to control a motion platform.
Stadsnära hav : en intervju/enkät om upplevelsen
The environment that surrounds us affects us all. Research
has shown that we feel physically and emotionally best in
natural environments with greenery or water elements. Urban
environments are likely to be more stressing then natural
environments. How we experience specific elements, as water,
of an environment is not as much investigated. There is a need
of further knowledge for us to fully understand the interplay
between our senses and the environment.
Human beings have always been depending on water and the
search for it has characterized our deeds and doings through
out evolution.
Energieffektivisering av aerbo reningsprocess : Tillsats av biprodukter i skogsindustriellt avloppsvatten
In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.
Inverkan av olika joner och jonconcentrationer på porstorleksfördelningen i trämassa-fibrer
The basic ingredient of paper is the individual wood fibers. The property of the fibers depends on a variety of factors e.g., method of pulp production and processing. The final sheet quality depends in part on how the fibers interface between each other and therefore factors that affect the fiber size are of interest.The flexibility of the fibers depends in part on the pore water i.e., the fiber swelling. The sheet becomes less flexible at low water content which gives a loss in strength. Thus it becomes desirable to increase the water uptake.The experimental investigation described in this report consists of exposing the wood fibers to different ions and ionic strength and then measure the pore size by thermoporosimetry where a DSC (Differential Scanning Calorimeter) is used.
?Vad är det jag gör egentligen?? - om att med videons hjälp bli medveten om helheten
This project consists of an adaptation, trial and evaluation of a model for practicing. Based on prior research I created a model aiming mainly to raise a musician?s self- awareness around the different parameters a performance consists of. An additional wish was for it to simultaneously assist the musician in monitoring his or her progress. With video recording and self-evaluation as the two main parts I tried the model by using it over a period of three months.
Multipel regressionsanalys av variabler som paverkar BNP
In this report a model was constructed in order to determine how a number of covariates influence the gross domestic product, GDP. The covariates were chosen depending on their expected influence on GDP, for example education and life expectancy. The data used in this report are collected from the World Bank. The model to describe GDP has been calculated using multiple line arregression. In order to reach a reliable final model the number of covariates has been gradually decreased to eliminate insignificant covariates.
Den positiva hälsovågen : En kvantitativ studie om hälsofrämjande arbete
The construction of buildings and paved surfaces changes the natural water balance.Precipitation generates surface runoff and storm water instead of infiltrating into the soil.Storm water has come to be considered as a major source of pollution in lakes and streams inthe vicinity of urban areas. Reduction of pollutants in storm water is a key action in order toprotect sensitive recipients and maintain high water quality. Storm water is traditionallytransported by storm sewers to the nearest recipient. In recent years the approach to stormwater management has changed; storm water should primarily be disposed of on site, throughlocal disposal of storm water, LOD. LOD is created by a combination of the function ofseveral smaller local facilities and the general sewer system.
Lillån : Statusbedömning enligt EU:s ramdirektiv för vatten
In Sweden, the County Administration board is responsible for improving the water quality in lakes and watercourses according to the European Union Water Framework Directive. In Västmanland county, where river Lillån is situated, the County Administration of Västmanland have the main responsibility for the aquatic environment in that area. The knowledge about the different watercourses in the chatchment of river Lillån is today limited. The aim with this study was to evaluate the ecological quality of River Lillån based on water chemistry analyses and benthic fauna investigations. The aim was also for the benthic fauna to compere different samplingsites and sampling methods with each other in order to see how the species composition changes in the river, and to see the advantages and disadvantages with different sampling tecniques.
Förbättring av den svenska kiselalgsmetoden-hantering av sedimentering
Benthic diatoms are used in Sweden for monitoring water quality in run-ning water; the method is also frequently used in other countries in Europe. One of the problems of the diatom method is the need for sedimentation of the fresh sample, to be able to decant the over standing water and add alco-hol as a preservations solution. To my knowledge, no results have been published about how long the settling time must be to ensure that the ben-thic diatoms really have settled down to avoid a loss of the diatoms when decanting the over standing water.
The aim of my investigation was to improve the Swedish method where the benthic diatoms are used for water quality monitoring. I wanted to find out the appropriate time necessary to wait until all diatoms have settled down before decanting the over standing water.
First, fresh benthic diatom samples were taken in the river Fyrisån and the lake Mälaren on different days. After arriving in the laboratory, I waited three different times (30 min, 60 and 180 min) for the diatoms to settle.
Utveckling och tillämpning av en GIS-baserad hydrologisk modell
A distributed hydrological rainfall-runoff model has been developed using a GIS integrated with a dynamic programming module (PCRaster). The model has been developed within the framework of the EU-project TWINBAS at IVL Swedish Environmental Research Institute, and is intended for use in WATSHMAN ? a tool for watershed management developed at IVL. The model simulates runoff from a catchment based on daily mean values of temperature and precipitation. The GIS input data consist of maps with soil type, land-use, lakes, rivers and a digital elevation model.
Koffeins påverkan på osmolariteten i tårfilmen
Purpose: The purpose of this study was to investigate if there was a difference in the tear film?s osmolarity before and after drinking coffee. 'Method: All subjects in this study were asked to fill in a questionnaire to diagnose factors in their subjective symptoms, the questionnaire TERTC-DEQ. The subjects with a total graduated points of over 17 were not allowed to participate in the further measurements. In the study there was a total amount of 38 subjects, were 5 participated twice for both measurements, coffee and water.
Att ta vara på solens fulla uppvärmningskapacitet
The purpose of this bachelor´s report is to expand the knowledge about heat supply of a small house in Malmö. The heat supply will be provided from solar panels in combination to two accumulator tanks which will storage the up heated water and a pellet boiler.The technique used here is warmth storage in water over seasons, which will provide the total need of heating for the house. Accumulator tanks in combination to solar panels gets more and more common in Sweden but this far it´s unusual to use it for storage over seasons. This report will highlight many of the difficulties associated whit heat storage and give information about a system's possible design and function.The design of this system is decided early on. An accumulator tank is placed 2 meters down in the earth on the backside of the house.
Uran i dricksvatten : litteraturstudie om reningsmetoder samt pilotförsök med jonbytesteknik
Uranium (U) is a naturally occurring component in bedrock and under the "right" conditions it can dissolve and move into the ground water. Since many people in Sweden depend on drilled wells as their main drinking water supply, they may be exposed to the uranium in the water.
Radioactive radiation is not the major concern associated with naturally occurring uranium. It is rather the chemical properties of uranium that make it a potential danger to human health. Uranium is proven to have toxic effects with respect to the functioning of the kidneys.