Sök:

Sökresultat:

1999 Uppsatser om Ground water modeling - Sida 23 av 134

Varför sviktar elevers intresse för matematiki de högre åldrarna? : Vilka faktorer ger elever motivationoch lust att lära matematik?

Drinking water is produced from raw water and is either from groundwater or surface water. This thesis aims to find out if the cleaning process of raw water is sufficiently effective. This is important because consumers are otherwise at risk of waterborne infection caused by pathogens. There are three groups of pathogens; bacteria, virus and parasite. These have different characteristics which mean that they require different water treatment to be separated.

Bestämning av dagvattenflöden i Knivstaåns avrinningsområde

The purpose of the thesis was to map the hydraulic load on the Knivsta river from stormwater runoff, and build a platform for further studies of pollution loads on the rivers ecosystems. New residential areas are planned to be built in Knivsta municipality and it will have an impact on stormwater flows to Knivsta river. To examine the impact this will have, simulations were made in the area as it stands today and after expansion work. The work includes calculation of flows from the populated areas but also from the catchment area around it consisting of woodlands and fields. Because of expected climatic changes which may affect rainfall, the simulations have been performed with different return periods for rainfall data.

Hållbara projekteringsverktyg : Från byggnadsinformationsmodell till simulering ? en utvärdering av Revit och Virtual Environment

This study examines the use of building modeling and energy simulations in the design process  of  a  building.  The  take-off  point  is  the  notion  of  energy  simulations  being needed early and throughout the building design process, and that the lack of energy simulations may be explained by the fact that they are time consuming and therefore often too expensive. A greater interoperability between software tools used by relevant disciplines,  such  as  the  architect  and  the  energy  specialist,  would  create  smoother workflows, which would reduce this cost and open up for more frequent and iterative energy  simulation  processes.  The  study  is  an  assessment  of  the  modeling  tool  Revit and  the  simulation  tool  Virtual  Environment  and  whether  they  can  create  smoother workflows, and make leeway for a more frequent use of energy simulations throughout the  design  process.  It  also  investigates  the  limitations  of  what  can  be  examined  by simulations in Virtual Environment. This will hopefully help clarify the future role of energy  simulations  in  design  processes.  The  method  is  a  trial  by  error  approach  of testing the two software tools by building and simulating a model. The results of these tests  show  that  the  workflow  is  not  optimal  (and  therefore  time  consuming)  for frequent  and  iterative simulations  throughout the  design  process,  but  it  also  reveals some  great  possibilities  of  what  can  be  performed  with  these  two  powerful  tools  at hand.  Further  development  with  regards  on  platform  independency  of  the  building information  model,  including  seamless  exporting  and  importing,  seems  necessary  to strengthen the future role of energy simulations..

Utveckling av hygienfunktioner i diskmaskiner : Desinfektion med ånga

This report is the result of a thesis work in Integrated Product Development, regarding hygienic features in dishwashers and especially disinfection by the use of steam.The thesis is performed at Electrolux Primary Development Dishcare in Stockholm and in collaboration with the Department of Machine Design at the Royal Institute of Technology.The targets of the thesis are to prove the advantages of a technology suitable to implement as a hygienic feature inside a dishwasher and to realize a functional prototype of a differentiated hygienic feature that does not exist on the market today.The process followed to perform the thesis is the process defined for Electrolux Primary Development.The technology chosen for development is disinfection by heating the water on the surface of the dishware, by the use of steam.A number of tests on how steam behaves when injected into the dishwasher tub have been performed, providing the results that have been taken in consideration when designing the prototype.The prototype consists of a pipe system provided with nozzles to eject the steam into the upper parts of the dishwasher. Tests of the final prototype show that thermal disinfection of water in a dedicated area of the tub can be reached within 9 minutes. The operation requires 0,17 liters of water and consumes 0.2kWh..

Ryskt luftmaktsanvändande i Georgien 2008 ? ett fall av Warden?

The Russian-Georgian war of 2008 drastically changed Europe´s and Sweden´s political climate.Russiashowed that it is capable of successfully completing complex campaigns including ground, naval and air assets. However, not much has been said about the theoretical framework and doctrine of the Russian military of today. Even less has been researched about Russian use of air power and applied air theory. Are air power assets still considered primarily as support of ground offensives or has the theoretical framework changed?John A.

Utvärdering av en FPGA för rymdbruk

A new FPGA suitable for space applications has just reached the market. To investigate whether there are any possible flaws or limitations similar to those previously seen on FPGAs, an evaluation has to be done. This master thesis contains the evaluation of this new radhard FPGA with focus on possible design limitations and package related electrical phenomena.Areas evaluated: Ground-/VDD bounce, Cross talk, Rise time sensitivit, Power cycling, Power consumption, Place and route tool, Radiation hardnessThis report contains all steps in the evaluation. From method to measurements, comparisons, theory, results and conclusions. In the evaluation work, special effort has been made to develop designs that really stress the FPGA to find potential problems.

LCA av dricksvattendesinfektion : en jämförelse av klor och UV-ljus

Disinfection methods for drinking-water produced at the two water works of Stockholm Water Co are compared in this study. Three different nethods are compared; disinfection with chlorine gas, disinfection with sodium hypochlorite and disinfection with UV-light and monochloramine. The method used is Life cycle assessment, LCA. LCA is defined as the compilation and evaluation of the inputs, outputs and potential environmental impact of a product system shroughout its life cycle. The environmental burden is compared for the three different disinfection methods.

Skaftslamkrypa (Elatine hexandra) i Bolmen, utbredning, tillväxt, reproduktion och styrande faktorer

The plants in the genus Elatine are characteristic for oligo and mesotrophic lakes. This study focuses on Elatine hexandra one of the four species in Sweden. It is stated as vulnerable by the National Environment Agency and a conservation plan with guidelines to preserve the plant in Sweden is under preparation. There have been a few previous studies investigating this plant in other countries but this is the first one for Sweden. The aim of this study was to investigate the distribution, growth and reproduction of E.

Förstudie för skapandet av ett miljöövervakningsprogram : en styrkeanalys angående vattendrag i västerhavets vattendistrikt för fastställandet av provantal i tid och rum för ett effektivt omdrevsprogram

The environmental monitoring in Sweden has been developed by several different parties and is now being coordinated and made more effective in order to meet the current demands on high quality information regarding the state of the environment. Sweden has been divided into five different water districts based on watershed areas because of requirements in the Water Directive of the EU. In Sweden there are two common types of environmental monitoring programs used to gather information on changes in time and in space. Currently both these two types are used for lakes in the water district of the western sea but only one is used for watersheds. The purpose of this report is to supply basic information regarding the possible need for a second environmental monitoring program for watersheds in order to better describe the spatial variation within the district as well as to determine the number of samples necessary in order to describe the district over time and space.

Bakteriell produktion i humösa istäckta sjöar i norra Sverige

The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.

Jordbruk och mjölkproduktion med kor i Etiopien :

Ethiopia is the country with most livestock per capita on the continent of Africa. There are 34.5 million cattle that are used for drought, meat- and milkproduction and 85% of the population rely on agriculture for their survival in some way. Milk is produced in four main systems, through pastoralism in the lowlands, in mixed crop-livestock systems in the highlands, in and near big cities with only one or two cows, and in intensive farming systems. There are 17 cattle breeds in Ethiopia and some of them are more suitable for milk production than others. Several environmental and economic problems arise from livestock holding in the country, for example overgrazing, low production due to feed shortage, low quality of the avaible feed and non-existing breeding programs.

Jämförelse av effekter från gruppträning i bassäng med landträning hos patienter med knäartros : Utvärdering av effekter på smärta, funktion i det dagliga livet och fritid- och idrottsaktiviteter

AbstractAimThe aim of the pilot study was to compare short- and long-term effects from group exercise in water with land-based exercise on pain at rest and pain with movement, along with the effects on function in daily life and practice of sports and leisure activities in patients with knee osteoarthritis. The aims were: Is there a difference in short- and long-term effects on pain intensity at rest and pain with movement after exercise in water or land in patients with knee osteoarthritis? Is there a correlation between the degree of pain intensity at rest and with movement, respectively and long-term effects from the two different exercises on function in daily life and practice of sports and leisure? MethodThe study was a randomized intervention study without a control group. Twenty patients with radiographic knee osteoarthritis were under a total of eight weeks treated with either land- or water-based exercise lead by a physiotherapist. The patients rated pain intensity at rest and with movement on a numerical rating scale (NRS) before and after the first training session, before and after the eighth training session, before and after the fifteenth training session and before the last and sixteenth training session.

Kundnyttan av Tekla Structures som verktyg i broprojektering

Byggbranschen är inne i en övergångsfas mellan 2D och 3D. BIM, som arbetsmetod, och 3D-modeller blir allt vanligare. I broprojekt är dock efterfrågan på dessa modeller låg. På WSP i Stockholm används 3D-modelleringprogrammet Tekla Structures i stor utsträckning på flera avdelningar. Önskemål finns om att utöka användningen av programmet även inom broprojektering.

Konceptframtagning av testinstrument för vattendetektion baserad på MIP

Water is vital for all life on earth. But it can also be dangerous, even fatal, if it is polluted water. 60 percent of child mortality can directly be deduced to dirty water. Not only developing countries are affected, even in the western world epidemics are breaking out by partake or bathing in dirty/polluted water.MIP, Molecularly Imprinted Polymers, is a biosensor technology that can provide faster and more reliable response than the current methods of water analysis. It is also cheaper and due to that more samples can be taken and analyzed.

Fuktskador i ytterväggar på grund av vattenintrång

Moisture damage in buildings is a serious issue that leads to problematic consequences and high economic costs. Despite the knowledge and awareness existing about moisture problems, extensive damager still occurs today. Studies of moisture in the exterior wall constructions shows that the issue if often caused by rain and water intrusion. These kinds of problem result in major costs usually because the companies have to replace the material and structural components and also in some cases tear down large parts of the buildings.The work includes moisture theory and descriptions of four different exterior wall constructions, wood stud wall with plastered facade, exterior wall with wood facade, exterior wall with concrete, and exterior wall with brick facade. Our thesis work describes how the constructions are affected and moisture damage due to water intrusion.

<- Föregående sida 23 Nästa sida ->