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4841 Uppsatser om Water model - Sida 20 av 323
Framtagande av en investerings- beslutsmodell för mindre tjänsteföretag
Problems:How would a decision model that takes into account more aspects and dimensions than just the financial aspect look for smaller service compa-nies? What aspects are important to consider in such a decision model?Purpose:The purpose of this master thesis is to develop a decision model based on previous research, to improve decision making in smaller service com-panies ? by considering perspectives that traditional investment calcula-tions ignore.Method:The study was qualitative and was based on both primary and secondary data. As data collection method for the development of the model we used literature search on previous research. The study?s primary data consisted of responses from five smaller service companies.
Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon
Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques.
The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.
En geopolitisk återkomst : Kultur, ekonomi och territoriell konstruktion i samband med inomstatliga konflikter
Through geopolitical theory this thesis explores how conflicts within states can be read and understood according to an analytical model determining one or several possible causes for the conflict. The model is created by the author and reflects geopolitical theory by giving three possible explanations to an intrastate conflict: culture, economy or territorial construction. The aim of the thesis is testing this model on two selectively chosen case studies ? i.e. two intrastate conflicts ? namely: the upcoming referendum in Scotland and the terror attack at Tiananmen Square in China.
Förutsättningarna för ett parallellt generation IV system vid svensk nybyggnation av kärnkraft.
A new build in the Swedish nuclear power system would entail increased re-quirements for the proposed repository, which is adapted after the reactors of today. With a fast reactor, capable of burning nuclear waste, operating in parallel with the light water reactors, the increased requirements on the repository could be reduced.In this thesis, simulations of a light water reactor and a fast reactor have been performed by using the Monte Carlo code Serpent to investigate the changes in the fuel inventory. The light water reactor in the study is a boiling water reactor and the fast reactor of the type sodium-cooled fast reactor and they have been used for three different operation scenarios.By studying the fuel composition and the results from the simulations of the three scenarios conclusions can be drawn. Conclusions regarding the change of the fuel inventory and decay heat in Clab as well as the interim storage facility and in the repository. Depending on the operation alternative the changes dif-fered significantly and especially regarding the mass of burned actinides for different fuels in the fast reactor.The lowest increase of fuel assemblies was meet when using 50 years old fuel with 20MWd/kg U burnout and 2,0 % enrichment for start up of the fast reactor and 30 years old fuel assemblies with 50MWd/kg U burnout and 4,7 % enrichment for the further operation of the reactor.The increase of the number of fuel assemblies was 3174, which is equivalent to 641tons of heavy metal.
Projektering av småhus med solvärme som huvudkälla
In this report a study has been done regarding different heating systems on which are the mostcomprehensive with solar heating systems. The report has also been focusing if solar power can beused as a primary heating source for supplying more than 50 % of the buildings total heatingproduction. The University of Dalarna constructed a demo-house for this purpose and according tocalculations the total solar usage is more than 50 %. This house has been made for referenceregarding the design of the heating system of property 5:37.Further studies have been made to compare different heating systems that are compatible with asolar system, where the compared systems purpose is to be independent of direct using electricity. Asystem of this design is regarded as sustainable according to environmental as economic issues.
Metodikmodell för styrning vid inköp
The work with this report has been focused on developing a methodology model for control at purchase. The methodology model covers parts classification, dispatching systems, batch shaping and more. The aim with the methodology model is that it will be used as an aid for a cost effective material planning to increase the value for customer.The work covers also a description of the present situation and the purchase process at Company X. Six parts have been applied, two from each class (A, B and C), in the methodology/model. The parts that have been applied are included in the flow between Company X and their supplier Company Y.Data have been collected trough literature studies, interviews and the company?s business system.
Informationslogistisk modell : Hur ska tillverkande företag tillgodose informationsbehoven?
This essay answers the question: How can a manufacturing business fulfill the information demand in the processes; purchasing, production, warehousing, order and delivery?The question has been answered through different kind of studies, such as literature, documents, Internet search, interviews and observations. The essay is written from a hermeneutic point of view and by using qualitative research. The result has been validated by two different manufacturing businesses.A simple information logistic model is the result of a comparison made between theory and empery. The aim of the model is to describe how a manufacturing business can fulfill the information demand by using different methods.
Avbördningsekvationer för sjöar utan vattenföringsmätningar
Stage-discharge equations for lakes without disharge measurementsSimon AnderssonIn 2015 all lakes, rivers, coastal water and groundwater should be of good ecological statusaccording to the water framework directive from the European Union. In the process ofimproving the quality of Swedish water bodies, knowledge of where problems occur isneeded in order to utilize the resources optimally. The ability of lakes to store water is animportant factor since it controls the flow of water through the country. A stage-dischargeequation is a mathematical relation between discharge from a lake and its water level. Bybetter understanding of stage-discharge equations for lakes, their storage capacity can bedescribed better in hydrological models.This master thesis aims to evaluate methods for determining stage-discharge equations forlakes where a variable amount of field measurements is available.
Aktivt system för tidvattenreglering av Lysekilsprojektets vågkraftsteknik
This report investigates a possible solution to the problem with adapting wave powerplants to work in countries with tidal water. The wire connecting the buoy at the surface with the generator at the bottom needs to adjust to the varying water depth. Our solution to this problem is to attach the wire to a jack which is then placed inside the buoy. The jack is then powered by an electric engine. The report discuss what forces the buoy will be exposed to and then the structural integrity of the design is evaluated through simulations.
ENERGIÅTERVINNING I GRANSHOT® - PROCESSEN
Uvån Hagfors Teknologi AB (UHT) has developed a process ? GRANSHOT® ? for quicksolidification of metals in water baths. In the process liquid metal is splintered ? granulated ?into small drops. The drops are rapidly cooled in a water bath where all the heat energy from theliquid metal is transferred into the water.
Kläder i hampa - ett miljövänligt alternativ/komplement till bomull?
Hemp has been used for textiles for a long time in history until it became illegal to grow in many countries in the 1930s. It is interesting from an environmental point of view because it doesn?t need any pesticides and in most locations it doesn?t need any irrigation either, compared to cotton, which normally requires big amounts of both pesticides and water for irrigation. Hemp is a bast fiber, which means that the fibers are located on the bast of the stem (on the outer layer of the stem). Therefore they cannot be spun directly, they have to be removed from the stem first.
Svartgran ? ett alternativ när allt ser mörkt ut? : en kartmodell för att visa lämpliga ståndorter för odling av svartgran
A common problem in forestry is plant death caused by frost. The risk of frost is highest on wind protected, flat or low-lying areas in the terrain. Here you often have regeneration problems with Norwegian spruce which is especially sensitive to spring frost. Swedish tree experiments have shown that the black spruce can be a suitable alternative on these areas, for example on moisture frost prone areas. The species originates from North America and its pioneer tree characteristics make it more frost hardy than Norwegian spruce.
Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser
Most of the saw and pulp industries have stored wood nearby their production, the main
reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality.
One drawback of wet storage of wood is the leaching of chemical substances into the
surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and
organic substances. These substances can cause problems for the surrounding environment.
The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.
Flödeslogistik vid Laponia Hotel
The aim of this report is to analyse the logistics of a medium sized restaurant and give an overall solution for improvements on the restaurant's logistics. The restaurant of interest belongs to Laponia Hotel and is located in Arvidsjaur, Sweden. Investments for over 100.000 Euros are planned for the hotel, which includes a reconstruction of the restaurant. The details on how the restaurant will be reconstructed are not yet known. I therefore chose to analyse the problemin general terms and find a solution that is focused on the logistic system itself rather than its layout.
Skötselåtgärder vid nyetablering av skyddszoner vid bäckar i södra Värmland :
Buffer zones play an important role for the water quality in our watercourses. When harvesting a forest close to a watercourse a buffer zone should be left. When it's not left, it will lead to radical changes in the environment for the water organisms. The overall purpose of this thesis was to illuminate the production- and environmental thinking when establishing new buffer zones in south of Värmland. The partials goals were to determine choice of tree species, ways of regenerate, occurrence of soil scarification and the occurrence of machine tracks in newly established buffer zones.