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1845 Uppsatser om Water exchange - Sida 40 av 123

IMO:s barlastkonventions konsekvenser för sjöfarten inom Östersjön

Arbetet behandlade vilka konsekvenser inom driften (ekonomiska kostnader och teknologi) som rederier kommer att drabbas av när IMO:s barlastkonvention träder i kraft då barlastvattnet måste renas innan inträde i Östersjön. Arbetets syfte var att få fram vilka konsekvenser det blir för rederier när IMO:s barlastkonvention träder i kraft. Resultatet skulle jämföra skillnaden mellan lag och rekommendation då Helsingforskonventionens rekommendationer baseras på IMO:s barlastkonventions krav. En kvalitativ metod valdes för att komma fram till resultatet, i form av en öppen intervjustudie, där fyra olika företag har intervjuats. Syftet med intervjuerna var att se ifall de följde Helsingforskonventionens rekommendationer och vilka konsekvenser det skulle innebära och skulle komma att krävas då Barlastkonventionen träder i kraft.

Undersökning av vissa beläggningars påverkan på antenners effektivitet i tågmiljö

For several years Uppsala University together with several companies has been involved in a WISENET project aimed at improving railway transport security. By placing a sensor system near the wheels of each wagon, the temperature of the bearings can be measured and transmitted to a collector placed centrally on the wagon. This in turn transmits the collected data to RFID receivers placed intermittently along the railway.As the signals are transmitted wirelessly, problems may occur as the antennas get dirty or coated with ice and snow. To determine the effects of these coatings, several tests were performed examining the reflection coefficient S11, the impedance Z11 and the efficiency eta of an antenna, and how they varied when various coatings were placed over the antenna. Examined coatings were ice, snow and water to determine the effects of weather, and various metal-based coatings: powdered iron both pure and partially oxidized, and iron ore granules.

Resonans

This report describes how the system may be exposed to oscillations and how this can lead to resonance. Resonance is a phenomenon that occurs when a system is affected by external periodic oscillations with frequencies close to the system's natural frequencies. Structures subjected to resonance can risk great damage and destruction, why resonance is something that is important to take into account when designing structures. Alternative ways to counteract resonance is to supply damping in the system. Damping means that the resonance decreases instead of letting the amplitude increase.The report discusses some examples on constructions that have experienced the effect of resonance.

VISION SJÖSTAD : Flytande Bostäder

Floating housing is a concept gaining ground in Sweden. The dwellings are different in many ways from traditional homes, not only regarding flotation, but also several other technologies. The purpose of this thesis is to emphasize the qualities that exist in living on water. The ambition was to present a proposal for a floating residential area located in Jönköping, containing homes of varying sizes, and to present their technologies. In order to find inspiration and solutions studies have been made on existing floating homes in Stockholm and Kalmar, focusing on their technical and functional solutions.

Karakterisering och klassificering av gotländska ytvatten enligt ramdirektivet för vatten

In this study the practical work with the EU Water Framework starts on the island of Gotland. 33 lakes and 32 streams have been characterized and classified regarding to their ecological status. The aim with the characterisation is to create a uniform discription of all waterbodies and a comparable estimation for the future. The aim with the classification is both to study the waterbodies ecological status and to gain knowledge of where the resources should be concentrated so that the ecological status in all waterbodies will be good in 2015.The characterisation has been done according to the EU Water Framework Directive, and the factors that have been applied are the mean depth and area of the lake. The length and size on the catchment area are the factors that have been used on streams.

Dynamisk massbalansmodellering av fosfor i Östersjön

During the past few years a vast amount of research has been done to increase the understanding of the complex ecosystem of the Baltic Sea. Modelling and simulations are important tools to increase knowledge of the system. A suitable model must be simple to use and the parameters and variables needed in the model must be easy to access.In this paper a dynamical mass-balance model, CoastMab, which is validated for smaller coastal areas, has been used to predict concentrations and transports of phosphorus in three large coastal areas - the Gulf of Finland, the Gulf of Gdansk and the Gulf of Riga. CoastMab uses ordinary differential equations to regulate inflow, outflow and internal flows. To reflect seasonal variations in temperature and different types of flows the model has a temporal resolution of a month.

Internrevisionens roll - ett svenskt perspektiv

The problem area was identified due to the fact that research within internal audit is fragmented and insufficient, simultaneously to internal audit becoming more common in the public debate. Crises and scandals in companies such as Enron in the US and Skandia in Sweden have resulted in new regulations regarding how companies should be governed. These regulations have been established in Sarbanes Oxley Act (SOX) in the US, and in Sweden the Swedish code for corporate governance will be implemented in 2005. The regulations imply that companies must provide sound internal control and to accomplish that, companies should have an auditing and consulting internal audit function. The Swedish code for corporate governance denotes that companies can decide to comply or explain why the code is not complied.

Idiopatisk cystit hos katt : en retrospektiv studie

Lower urinary tract diseases are a common problem in cats all over the world. The symptoms are for example dysuria, pollakuria, stranguria, periuria and hematuria. In approximately two thirds of these cats the underlying cause is not known and the disease is therefore called feline idiopathic cystitis (FIC). We need to know more about the disease to get a consistently effective treatment and prevention. A retrospective study was performed in 50 cats with symptoms of FIC and where other causes of inflammation were ruled out. Data like breed, age, sex, body weight, feeding, therapy and therapeutic results were collected, also if it was an indoor or outdoor cat, duration of the symptoms, if there was any stress and if the cat was living with another cat.

Spårning av miljöstörande ämnen i Uppsala stads spillvattennät

To the sewer systems households, industries and other activities are connected. The wastewater is collected at treatment plants where a nutritious sludge is produced. The sludge does not only contain nutrients, but also hazardous substances originating from different activities in society. To reduce the flow of hazardous substances to treatment plants and to create a sustainable recycling of plant nutrients the Swedish Water & Wastewater Association has developed the certificate system REVAQ. This certificate requires a good quality of the sludge but also that the treatment plants maps the origin of the unwanted substances.

Skadliga nollflödespunkter i Fortum Värmes fjärrvärmenät i Stockholm : En analys av dess förekomst och effekter

When several production units provide a district heating network, water is pumped from different directions. When the flows from the plants finally meet in the network, the water can be completely still. These places are called zero flow zones. In district heating networks with several plants, which also have different supply temperatures, large and frequent temperature fluctuations can occur when the zero flow zones move. This may cause wear on the pipes, a phenomenon called low cycle fatigue.For this reason it is important to examine where and when zero flow zones that cause temperature changes occur.

Elektrolytlösningar som vätsketerapi hos mjölkkor med löpmagsförskjutning :

Ten cows suffering from displacement of abomasum (DA) were treated with two different electrolytesolutions. The DA cows showed symptoms typical for the disease. Four out of 10 cows had a metabolic alkalosis and two a metabolic acidosis. The cows were mildly hypocalcemic, and 9 out of 10 were mildly to moderately hypokalemic. Six out of 10 cows showed muscle fasciculations.

Lean Healthcare på Akademiska sjukhuset i Uppsala : En kvalitativ studie om hur läkare upplever att den professionella autonomin påverkas av Lean Healthcare

This study aims to evaluate the value relevance of Piotroski?s (2000) nine fundamental signals. In order to do this, the signals are tested on the OMX Nordic Exchange Stockholm between the years 2003 and 2009. The hypotheses of the study are whether the signals are value relevant and if the value relevance has changed. To test this, a Chi-square test and a regression are used.

Sammanvägda avrinningskoefficienter i rationella metoden : en jämförelse mellan idag och 1970-talet

Storm water is rain and melted snow that runs off, primarily from impervious surfaces.Future storm water management is facing the challenges of increased precipitation, asclimate changes, and increased areas of impervious surfaces due to the expansion anddensification of the cities. Impervious surfaces reduce the potential for water to infiltratein the ground leading to increased surface runoff and higher peak discharge.The runoff coefficient is closely related to the percentage of impervious surfaces andrepresents the maximum percentage of a catchment that can contribute to runoff. In thisstudy, the objective was to evaluate the weighted runoff coefficient for three differenturban types; apartment buildings, townhouses and residential areas and a comparisonbetween today and the 1970`s was made.The runoff coefficient was determined by manual mapping of the different surface typesin each area based on data in the form of orthophotos and aerial photographs. The surfacetypes that were mapped were asphalt, permeable areas, tiles, sand/gravel and roof.Tiles and sand/gravel were the most difficult surface types to map. In order to see towhat extent these categories influenced the weighted runoff coefficient a sensitivityanalysis was carried out and the runoff coefficient based on surface type was changed indifferent scenarios.The results of the sensitivity analysis showed that the surface types tiles and sand/gravelhad little impact on the weighted runoff coefficient which in mainly due to the fact thatthe percentage of these surfaces types of the total area is small.The result of the study showed that the largest change in the runoff coefficient occurredin residential areas where the increase in the percentage of impervious surfaces causedby new roofs in the form of porches and garages and from paved or tiled driveways.

Rostfärgat slam i dränagesystem vid vattenkraftsanläggningar : orsaker och åtgärder

From embankment dams is something that has long been noticed and given rise to different questions. The most serious question is if the sludge is a result of inner erosion through the dam, and thus consists of material transported from the dam. Concerns have also been raised whether the sludge could interfere with the systems drainage capacity and thereby lead to high pore pressure in the dam, or if the measurement of seepage is disturbed, as the measuring is usually made via Thomson weirs, which could risk being blocked. The result of this investigation shows that the sludge is a result of the oxidation of iron by iron bacteria, and to the greater part consists of these oxides as well as the bacteria?s own structures. The iron oxidizing bacteria, FeOB, oxides ferrous iron to ferric as a part of their metabolism, and thereby create large quantities of iron(oxy)hydroxides.

Luft/luftvärmepump : - Med möjlighet till återvinning

Sweden has long had access to low electricity prices due to the wide availability of hydro and nuclear power. This has now changed because of today's rising electricity rates resulting in increasing heating costs for properties, especially in the properties with electric heating systems."Ankaret" is a parish for "Svenska Alliansmissionen", which is located at "Gullbrannagården".The parish has installed electrical radiators and an exhaust ventilation system that makes the energy demand high due to the large ventilation flows. The building was built as the price of electricity was still low and would reduce energy use today by combining its heating system with an air/air heat pump. The heat pump delivers more heat into the room than the electrical energy that it uses. This lowers the electricity needs.

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