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4841 Uppsatser om Water model - Sida 35 av 323
Rocchio, Ide, Okapi och BIM : En komparativ studie av fyra metoder för relevance feedback
This thesis compares four relevance feedback methods. The Rocchio and Ide dec-hi algorithms for the vector space model and the binary independence model and Okapi BM25 within the probabilistic framework. This is done in a custom-made Information Retrieval system utilizing a collection containing 131 896 LA-Times articles which is part of the TREC ad-hoc collection. The methods are compared on two grounds, using only the relevance information from the 20 highest ranked documents from an initial search and also by using all available relevance information. Although a significant effect of choice of method could be found on the first ground, post-hoc analysis could not determine any statistically significant differences between the methods where Rocchio, Ide dec-hi and Okapi BM25 performed equivalent.
Sedimentprovtagning av dagvattendammar som ett alternativ till flödesproportionell vattenprovtagning
Stormwater run-off from surfaces such as roads or rooftops is often polluted with heavy metals and nutrients. Many of these substances can cause great damage in biota if they end up in the recipient. In Sweden constructed wetlands and ponds for treatment of stormwater are frequently used, since research has shown that these treatment ponds are reducing stormwater pollution considerably to a low cost. The knowledge of these pollutant removal mechanisms and how follow-up and assessment of the ponds should be performed is still limited.To determine the pollutant removal efficiency of the stormwater ponds it is recommended that flow-weighted water samples are collected from both the inflow and the outflow of the pond. This method demands considerable resources of time and money for installations and analysis.
Termomekanisk utmattning av Sanicro 25 : Materialmodellering med finita elementmetoden
The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal ? and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well.
Utvärdering av fosforläckageefter stallgödsling med hjälp av lysimeterteknik : Evaluation of phosphorus leaching aftermanure application using lysimeter techniques
Based on laboratory studies with lysimeters, the concentrations of dissolved reactive phosphorus(DRP) and particulate phosphorus, which is the main part of other P (OVRP), has been studied inpercolating water. The experiment was conducted through irrigation of small soil columnscontaining clay topsoil from an experimental field in Västergötland. Three rain simulations wereconsecutively performed. DRP concentrations in the percolating water ranged between 0.2 - 0.3mg·Lclearly related to the phosphorus concentration in the soil, measured in a soil extract ofammonium lactate (P-AL). Concentrations of OVRP were relatively low and ranged between0.12 and 0.16 mg·Lwas not proven and the experiment may reflect how a relatively slow percolation of water mayrelease DRP.
Utveckling av lastmodell för Uppsala fjärrvärmenät
The aim of this study was to develop a load prognosis model for Uppsala district heating system to be used as a tool for heat production optimization. The methodwas to build three models for the different customer types; housing, industry andoffices and then scale them for the total system using data from Uppsala districtheating system. The heat load consists of two parts, one that is temperaturedependent and one that is dependent of the social behavior of the customers. Thetemperature part was modelled with an ARX model using an outdoor temperatureprognosis as input signal. The social behavior part was modelled using the mean ofthe social behavior from some days before and additionally by distinguishing betweenweekdays and weekends.
Kunskapsteori och kunskapsorganisation: En diskursanalys
This Masters thesis concerns epistemology in Knowledge Organization KO, as a field of study in Library and Information Science LIS. Using a theoretical model by Birger Hjørland and foucauldian discourse analysis as springboards, this study analyses three epistemological discourses in the practice of KO. The aim of the study is to show how these discourses are constituted and demarcated in relation to KO, as well as to examine how they fit into Hjørlands model. A brief historical outline of some epistemological trends in LIS is sketched, as well as examples of how different epistemological schools influence different parts of KO, e.g. information retrieval, indexing- and classification theory.
Modellering av reserv- och nödkraftsystem i JAS 39 Gripen
Simulation is a vital tool during development of JAS 39 Gripen, since money and time can be saved.The Auxiliary and Emergency Power System, AEPS, is a subsystem of the secondary power system in Gripen. It has the function of providing the aircraft with electrical and hydraulical power before activation and after deactivation of the main engine. The system also functions as backup in case of a safety critical problem in the main power supply system. The system basically consists of a control unit and an auxiliary gearbox. The gearbox is driven by an air turbine.
Näringsämnesretention i fyra nyanlagda våtmarker i Falkenbergs Kommun
This study evaluates the retention of nitrogen and phosphorus in four newly constructed wetlands in the municipality of Falkenberg, Sweden. The four wetlands have been selected because they have been specifically constructed with the aim to reduce nitrogen and phosphorus in farming areas. The process of selecting the specific wetlands has been done in collaboration with the county administration in Halland. Through field studies in collaboration with the landowners where the wetlands are sited, the areas that provide the wetlands with water were determined. The size of these drainage areas were determined in a GIS computer program. The type of land use within the drainage areas was also determined.
Metoder för prediktion av kardiovaskulär sjukdom med njurfunktionen
This study examines if the prediction of cardiovascular disease in hypertensive patients can be improved upon when renal function and microalbuminuria are added to the classical risk factors The predictive capability of a model is measured by discrimination, calibration, reclassification and Harrell's C.The results are ambigious. In most cases, microalbuminuria should be included in the model, but the results regarding the other measures of renal function are varied. Therefore, the selection of risk factors to include in the model depends on which measure of prediction one prioritizes..
The effect of vegetable fat on cheese yield and cheese properties
The production of cheese is in continuous development with objectives to in-crease productivity, achieve changes in shelf life and functional properties of the products. One concept in the development is to substitute milk fat with vegetable fats and oils in the manufacture of cheese.
The objective of this study was to investigate effects on cheese yield and cheese quality of 4 different semi-hard analogue cheese products produced by substituting milk fat with vegetable fat, each analogue cheese with a specific mixture of vegeta-ble fat. As reference a cheese produced with anhydrous milk fat was used.
The yield and recovery of fat and protein were determined by recording the weights of each cheese direct after press and after 20±2 days of storage and analysis of the composition of the cheeses after 20±2 days of storage. The cheese was fur-ther subjected for texture profile analysis in a TA-XT Plus Texture Analyser and analysed with Differential Scanning Calorimetry (DSC) to examine whether the fat behaves similar in the cheese as in pure form in respect to its thermal properties.
The cheese yield was not significantly different when using different fats. Differ-ent amounts of water were absorbed during the water cooling.
Den traumatiserade sexualiteten : En litterär motivstudie av sexualitet i Raymond Carver's "So much water so close to home"
Denna studie erbjuder en litterär analys av gestaltandet av sexualitet i den amerikanske författaren Rymond Carvers novell "So much water so close to home". Analysen lyfter bland annat fram den obligatoriska heterosexualiteten som den teoretiseras av Adrienne Rich och hur manlig kontroll av kvinnans sexualitet inom den heterosexuella institutionen tar sig uttryck i texten.Utöver det undersöks i analysen vilka principer som kan anses ligga bakom konstrueringen av sexualitet i novellen samt hur dessa tar sig uttryck. Den aspekten av analysen tar avstamp i Judith Butlers teori om diskursivt skapade kön och genus samt den heterosexuella matrisen som utgångspunkt för all sexuell åtrå. .
Textilindustrins avloppsvatten och avloppsslam ur ett miljöperspektiv : Underlag för internationella riktlinjer inom projektet Sweden Textile Water Initiative
The aim of my thesis is to obtain knowledge of textile wastewater and textile sludge from an environmental perspective, which can be used as a basis for the ?Sweden Textile Water Initiative? guidelines for a sustainable sludge management. In my study I have mainly focused on textile dyes, salts and metals and their routes during wastewater treatment.This paper is partly a literature review, which I began by identifying the pollutants discharged from each textile process. Then I studied wastewater and sludge quality, environmental aspects, possible treatment and recycling methods. I have also tried to find existing type of guidelines in order to make comparisons.
Konstruktion av testrigg för moderna ångexpandrar
This report summarize what have been done during the Master of Science Thesis that Klas Schjelderup has written for the company RANOTOR Utvecklings AB. The company is developing modern steam engines and this work should develop a machine to perform tests on a new type of piston seal that hopefully could be used in the future. The steam engines will be both volumetric and energy compact, around 1600hp/literof cylinder volume, and it will have a lot of practical applications.The new type of piston seal is hydrostatic lubricated which means that a fluid is separating two faces that normally is in contact. In this case pressurized water is used to separate the piston seal from the cylinder wall. RANOTOR have earlier formulated that at least the expander in the modern steam engine have to be oil-free, due to other components functionality in the closed water system.
Modellbaserad systemutveckling i komplexa verksamheter. En fallstudie av Coremetoden
In system development it is today increasingly common to use a model-based system development method. These methods that are suited for Agile work with simple and quick updates and implementations of new applications in systems conform to the requirements that are becoming more important today, namely more flexible and less expensive system that still maintain high quality and safety.A company that has been working with this type of system development method for a long time is Genicore AB, which also has developed their own tools and model language in order to better model the information management systems in complex and abstract operations. Genicore AB is trying to spread their method other developers and have therefore taken the initiative to start this study. The method is evaluated and tested by two students with relatively little experience in model-based systems engineering in order to gain a new perspective on how the method functions. The method has been applied to an educational activity in order to test it in a new domain, and this led us to our research question;?What criteria are of particular relevance in the implementation of a MBSD method on on complex businesses??Through literature reviews and interviews, we formed an idea of how model-based system development works from a theoretical perspective, and then continued to the case study conducted on the educational activities at the faculty of IT at University of Gothenburg.
Ett företags internationaliseringsprocess : - i ett land kulturellt skilt från dess hemmamarknad
AbstractPurpose:The purpose of the study is to describe the internationalization process of one firm when in a country culturally diverse from the firm?s original market.Methodology/approach:The study is a single case study which examines one firm?s internationalization process when entering the Chinese market. The approach has been an empiric interaction between empirical and theoretical data.Findings:The theory of the Uppsala model was applied to the case-company to test the model?s completeness. The authors found weaknesses and added three more aspects to the model.