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1524 Uppsatser om Sub surface flow wetlands - Sida 11 av 102

Del projekt inom ClampCal - Utvärdering av mätmetoder för temperatur, viskositet och densitet samt röregenskaper

The dissertation were performed on SP, Technical Institute of Sweden. The dissertation were carried out on the measurement technical department, this dissertation is a part of a bigger project, project ClampCal. One of SP?s returning assignments are flow-measurement. When flow-measurement is performed, the flow has to be stopped so that a meter can be installed in the pipes where measurement is going to take place. At every stop there is time delay in the flow which causes the customers to loose money. This is why SP wanted to find a better solution so that measurement can be done without any stops in the flow. Usage of a so-called Clamp-on meter was considered, but since the measurement uncertainty is too large it takes some investigation on the parts where the largest uncertainties occur and thus find a solution that can diminish the uncertainty as much as possible. The parts that were considered to have an opportunity to reduce measurement uncertainties were the fluid temperature, its characteristics and the pipe geometry and its characteristics. For the fluid temperature a Pt100-sensor with four different radii for various pipes was used.

Växters förmåga att ackumulera metaller : Vass, bredkaveldun och gäddnate i Bergviks dagvattendamm

AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.

Förslag till energieffektivisering och energideklarationsunderlag : Munkebergsskolan och Bredängens äldreboende i Luleå

This examination work is performed at the institution of industrial economy and production at Jonkoping technical university, for JELD-WEN Door Solutions plant in Forserum.Today the focus in the company is on to reduce their inventories binding of capitals as well as inventory of products and that includes to get a good control of the supply and handling of material which is of great importance.JELD-WEN Door Solutions is one of the worlds leading producers of windows and doors and the head-office is located in Oregon, USA.A great number of wooden doors are manufactured by the company in varying of constructions, classifications and performance.The production of the plant in Forserum has a project- and customer focus manufacturing where only internal doors are produced. The overall market they are concentrated on is to different institution such as schools, hospitals etc.The purpose of this work is to investigate possibilities to improvement of material- and production control at JELD-WEN. The report will handle the master production schedule to and from the production divisions within manufacturing industry. Focus will be on the way for information- and material flows from arrival, transport within the company and further on to customers.Further a map of the flow was performed which gave a clearer picture of the connection between the flow of information- and material for the manufacturing process. On the basis of the mapping of the flow, the group discovered that the flow of material had some improvement potential.

Design för Flow : En analys av designkriterier för användbarhet

Human Computer Interaction (HCI) handlar om att utveckla produkter med god användbarhet. Med användbarhet menas att system ska vara lätta att använda och lära. Jakob Nielsen är en av förgrundsfigurerna när det gäller riktlinjer för hur detta ska uppnås. Han har utvecklat tio kriterier som kan användas för att ett så bra system som möjligt ska kunna utvecklas.På senare år har forskare börjat se till, inte bara tekniska aspekter utan även till de känslor som användaren kan tänkas uppleva under det att denna interagerar med en webbsida. Ett flertal forskare har utvecklat teorier kring begreppet Flow.

Akustisk design av studiorum för musikinspelning

Detta projekt genomfördes i samarbete med akustikern Erling Nilsson på företaget Ecophon i Hyllinge. Uppdragsgivare var musikproducenten Magnus Ågren som äger studion Flow Music i Malmö. Uppgiften var att förbättra akustiken i ett av Flow Musics studiorum. Rummet hade före projektet en hård och obehaglig akustik. För att komma fram till ett åtgärdsförslag specificerades först hur enskilda akustiska egenskaper skulle påverkas för att ge ett så bra resultat som möjligt.

Opera i Stockholm, Stadsgårdskajen

The report is about efficiency of a current production group where there is no clear production flow and there are some buffers between the operations. The efficiency is done with the help of a tool that is calledWork process of flow production which is used by Atlas Copco CTO. The most obviously results are that the lead time drops from 25 hours to 425 minutes and that the balancing loss decreases from 85 % to 8 %. The report focus on decreasing transports, decreasing buffers, more reliability in lead time and quality. And a more stimulating labour content for the workers is another result..

En tand för en tand och en våtmark för en våtmark - ett återskapande värt pengarna? : En undersökning av nyttan och kostnaderna av att restaurera våtmark med hjälp av Contingent Valuation Method.

The goal of this study is to examine what five teacher?s impression of the teacher?s role is in their previous years. How important the ?joy at work? is in relation with the educational progress? And what aspects that contributes to the? joy at work? and what obstacles that stops them. The essay will also go through the concepts of a teacher role, with connection to the theoretical perspectives of Csikszentmihalyi?s Flow and Antonovsky?s Salutogenesis (KASAM).The method I used was interviewing five teachers and I used Larsen?s chapter of ?content analysis? as a basis, I also used Flow and KASAM as theoretical references in my analysis.

Sänkta sjöars inverkan på ytvatten i Västerbottens kustland : Samband mellan sänkningsnivåer och vattenkemi i sjöar på sulfidrika sedimentjordar

Lake lowering in sulphide-rich areas is currently a major environmental impact for surface water. This study focuses on whether there is a relationship between a gradient of lake lowering and surface water impacts in areas of sulphide-rich sediments, in order to better understand their contribution of heavy metals and sulfuric acid. Also, is it a reasonable method to use the reduced lake area in order to quantify the gradient? The survey was conducted by collecting water samples from reference lakes and lowered lakes from south to north in coastal areas within the county of Västerbotten. Water samples were then analyzed for TOC, pH, conductivity, anions, base cations, alkalinity, acidity, sulfate, Al, Cd, Fe, Mn, Cu, Zn and Pb.

En flödesutjämnande driftstrategi för Uppsalas fjärrvärmesystem : En ändrad styrning av framtemperaturen

This thesis examines a possible control strategy to minimize flow fluctuations in Uppsala?s district heating system. High variations in flow rate may lead to complications caused by hydraulic constraints in the district heating system. These complications, such as inadequate pressure and temperature levels, increase the risk of heat delivery failures. It is therefore important to avoid such situations both for the producer and for the customers.Typically, the forward temperature is controlled by using a rough correlation with respect to the outdoor temperature.

Utvärdering av den biologiska reningen av processavloppsvattnet vid GE Healthcare i Uppsala

GE Healthcare operates in Uppsala (Sweden) and develops systems, equipments and medium to purify medical substances. Discussions with the local authority concerning planed far-reaching changes and upgrades of the biological process techniques for sewage management, aroused the question about revising the terms of permit for the activity. Therefore it seemed necessary to evaluate a newly installed biological process technique, which is the background of this thesis. The evaluated biological treatment process was built in 2003 and consists of a biological reactor filled with moving bed carriers with a high surface area for biological growth. At the time of the project the biological wastewater treatment plant consisted of a flow equalization facility and two following parallel biological processes; a biological reactor with moving bed carriers and a tower trickling filter.The aim of this thesis was to survey the function of the biological reactor with respect to the reduction of organic matter.

Effektivisering av produktionsgrupp : Improving the efficiency of a production group

The report is about efficiency of a current production group where there is no clear production flow and there are some buffers between the operations. The efficiency is done with the help of a tool that is calledWork process of flow production which is used by Atlas Copco CTO. The most obviously results are that the lead time drops from 25 hours to 425 minutes and that the balancing loss decreases from 85 % to 8 %. The report focus on decreasing transports, decreasing buffers, more reliability in lead time and quality. And a more stimulating labour content for the workers is another result..

Prefabricerade stödmurar i betong :

This is a booklet with information and inspiration about precast retaining walls. The three chapters contain information about concrete as a material, how the surface of the wall can be altered, and a chapter with ideas for a new precast wall. I have obtained information through books, interviews, lectures and fairs. The retaining walls on the market do not correspond to the requirements of the Landscape Architects I have interviewed. I have therefore considered their opinions in the chapter containing my new ideas for new retaining walls.

Simulering av översvämningar i Nedre Dalälven

Mosquitoes are found in extremely large numbers in the lower parts of the River Dalälven. In the year 2000 the mosquito nuisance was especially high, resulting in foundation of the Biological mosquito control project. Since 2001 mosquito larvae are controlled by using a biological pesticide BTI (Bacillus thuringiensis ssp israelensis). The mosquito fauna in the area is dominated by flood water mosquitoes, a group of mosquitoes that are very aggressive and form new generations of mosquitoes during every single flooding event during the summer. To be able to efficiently control the mosquitoes it is essential to know the extension and locality of the flooding.

Förändringar i markanvändning över tid och dess påverkan på vattenkvalitet

The EU Water Framework Directive has led that management follows the boundaries of natural catchments.The Swedish waters suffer from a nutrient overload that originates mainly from diffuse sources such as agriculture and the subcatchment of Hackstabäcken in Vallentuna Kommun, just north of Stockholm, has been chosen for this study because of its high nutrient load and because it has undergone obvious changes in land use through the years.In this study, the land use in 1902 is compared with the land use in 2011 in order to investigate if it has influenced the ability of the landscape to produce ecosystem services related to nutrient removal. These services will continue to be produced as long as the system is stable and resilient, but when landuse changes and manure from horses increases it will lead to disturbances that can convert a system from one regime in to a completely different one. That will result in loss, or degradation, of ecosystem services such as denitrification, phosphor sedimentation and adsorption, vegetation uptake and infiltration.The results of this study are based upon area calculations of landuse from old maps from 1902 and 2011. Through these maps it becomes clear that the forests in Hackstabäcken, has increased with 170 ha together with an urbanization of 311 ha, at the same time as wetlands and arable land has diminished and lakes has suffered from reductions. Wetlands have been reduced with 76 ha and the ones remaining are of insufficient quality from a nutrient removal perspective.Data from 1902 and 2011 regarding number of horses and bovines indicated a decrease in bovines and an increase in horses.

Syntes och egenskapskarakterisering av volframoxid framställd med magnetronsputtring

The system tungsten-oxygen has potential of being suitable for decorative coatings since ceramic coatings are often hard and wear resistant, and since modulations in oxygen content or incorporation of small ions could give bright colours. The aim of this report was to investigate the relationship between process parameters and  the properties of the films, with the wear resistance being of special interest.Samples with tungsten to oxygen ratios in the range of 100:0 to 25:75 at% were made using reactive sputter deposition, either with constant gas flow, or gas flow controlled by optical emission of the plasma. The hysteresis of the system, which means that a certain gas flow will cause different pressure and/or target voltage depending on in what way the flow is reached, makes it interesting to control the process where the system makes the steep change from metallic tungsten to ceramic tungsten oxide. This is difficult and thus requires precise control equipment.The samples were analysed using X-ray diffraction, X-ray photoelectron spectroscopy and an empirical wear test suitable for small components like cell phone cover for example, in order to characterize the structure, composition and wear resistance of the coatings. The results could be divided into three groups: (I) tungsten-like, with very low oxygen content; (II) mixed phase and (III) tungsten oxide like, with oxygen content close to 75 at%.

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