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500 Uppsatser om Sub surface scattering - Sida 4 av 34

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.

Uppvärmd konstgräsplan : Beräkning av utnyttjningstid för en uppvärmd konstgräplan med alternativa rörplaceringar

For Skattkärr IF a turf field with warming has been projected to increase field?s utilization hours and to have a longer period for athletes to perform their activities outdoors. The technique chosen to heat the plan is a type of a geothermal heating system without a heat pump. The brine, which is water with 30% ethanol, collects heat from the borehole and discharges it to a coil in the field. There is at position 11 boreholes but it is planned to increase the number to 31, which is the design for the facility.

Shamyana, the out door pleasure

The present work is a continuation of the ideas developed in previous projects during my Masters studies that explored the relation between pattern, form and space. Starting from the pattern multiplication for space construction the present project proposes textiles as an assortment of flexible expressions. The purpose of the project is to explore aesthetic and functional potential of textiles for out door temporary structures. This is to create a pattern interface which filters sunlight through a textile surface to offer instant sheltering solutions for out door activities. The project combines research and analyses of outdoor temporary structures and scope of textile in the area.

Computer Modelling of the Influence of Surface Topography on Water Repellency and a Study on Hydrophobic Paper Surfaces with Partly Controlled Roughness

A computer model based on minimization of the free energy, capable to predict contact angles and spreading transitions between Wenzel and Cassie mode for drops placed on surfaces with different topography were implemented in matlab. Simulations were compared with experiments documented in the literature. These showed that reported transitions between Cassie and Wenzel mode can be explained by minimization of the free energy. In this report, a study on the possibility of constructing water repellent paper surfaces with a combination of treatment with octadecyltrichlorosilane and topography changes, is included..

Stump treatment with the root rot antagonist phlebiopsis gigantea : - sensitivity of P. gigantea spores to high pressure stress; - reduced water consumption for stump treatment

Stump treatment today requires large quantities of clean water mixed with the protective product Rotstop, to fully cover the stump surface. In order to reduce the water consumption without reducing the coverage of the stump surface, the pressure in the stump treatment device can be increased. Therefore, the Phlebiopsis gigantea (Fr.) Jül. suspension used as a biological control agent to prevent Heterobasidion annosum (Fr.) Bref. infection was pressure-tested.

En jämförelse mellan TLS och UAV-fotogrammetri : Inmätning av hårdgjorda ytor

At present day there are several different methods for measuring of paved surfaces.The most common methods today are measuring with a total station, the GlobalNavigation Satellite System (GNSS) and terrestrial laser scanning (TLS). Recently thedevelopment of unmanned aerial vehicles, known as drones, has increasedexponentially and today there are several ways of using drones for measuring surfacesby photographing and laser scanning.This thesis contains a comparison between the methods terrestrial laser scanning(TLS), and unmanned aerial vehicle photogrammetry (UAV). The measurements havebeen applied on two different test surfaces, one of asphalt and one of gravel. Thepurpose of the comparison is to investigate whether the airborne photogrammetry isequivalent accurate in its height levels as the terrestrial laser scanning. For thecomparison to be more extensive, these two methods have not only been comparedin precision but also in the areas of ease of use and economy.The precision was analyzed by comparing the height levels in randomly placed controlpoints on the test surfaces.

Energy efficient storage of biomass at Vattenfall heat and power plants

Storage of biomass is often associated with problems such as heat development, dry matter losses and reduction of fuel quality. The rise in temperature can potentially cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles can cause health problems in the surrounding. The dry matter losses and reduction of fuel quality can have economical effects. The aim of this thesis project is to develop guidelines on how to store large amount of biomass at Vattenfalls heat and power plants in an optimal way.

Objektspecifik möbeltextil

My project aims to understand more about the methods used in making woven textiles on an industrial level, and how these tech¬niques can be adapted to create object-specific pieces. On visiting the furniture fair in Stockholm, I was surprised to see that most of the textiles used for furniture were so similar, despite the variation in the furniture itself. My project is about creating textile patterns that are specific for each piece.The idea behind the process could be used for any product, but the pattern I created is specifically for the armchair Accent by Yngve Ekström. I wanted to create the feeling of a pattern moving over the surface of the object and adjusting to it. I worked primarily with differences in density.

Polyuretansvamp i kontakt med papper - en jämförande studie inom konservering

Uppsats för avläggande av filosofie kandidatexamen iKulturvård, Konservatorprogrammet15 hpInstitutionen för kulturvårdGöteborgs universitet2014:03.

Fluid Simulation for Visual Effects

This thesis describes a system for dealing with free surface fluid simulations, and the components needed in order to construct such a system. It builds upon recent research, but in a computer graphics context the amount of available literature is limited and difficult to implement. Because of this, the text aims at providing a solid foundation of the mathematics needed, at explaining in greater detail the steps needed to solve the problem, and lastly at improving some aspects of the animation process as it has been described in earlier works. The aim of the system itself is to provide visually plausible renditions of animated fluids in three dimensions in a manner that allows it to be usable in a visual effects production context. The novel features described include a generalized interaction layer providing greater control to artists, a new way of dealing with moving objects that interact with the fluid and a method for adding source and drain capabilities..

Ämnestransport med grundvatten i hydrogeologiska typmiljöer

Certain types of waste, e.g. bottom ash originating from municipal solid waste incineration (MSWI bottom ash) can be used as road construction materials. A potential problem is the possibility of substances leaching out of the road and spreading in the surrounding groundwater.The aim of this master?s thesis is to conclude whether hydrogeological type settings can be employed to, based on local conditions, provide an estimate of the probable spreading of these substances in the surrounding groundwater, and whether certain types of soils can be identified as being less suitable for the localization of a MSWI bottom ash road. A hydrogeological type setting is defined as a mappable unit with similar hydrogeological properties.

Analys av haptoglobin i bovint serum med surface plasmon resonance biosensorteknik :

The concentration of acute phase proteins in serum is altered as a response to inflammation, infection or trauma. this makes these proteins potential biomarkers of unspecific pathological processes. In cattle, haptoglobin and serum amyloid A are the two acute phase proteins that show the largest increase in serum concentration as a result of inflammatory processes. The haptoglobin concentration has been shown to correlate to clinical signs as well as inflammatory processes found at post mortem examination. This feature could be useful prognosis of the individual as well as for monitoring the health status of a herd or identifying carcasses that shold be examined closer at the slaughter-house.

Hållbar vattenförsörjning i områden med vattenbrist : Sustainable water supply solutions for areas affected by water shortage

In some coastal areas in Sweden water shortage sometimes appears because the withdrawal of groundwater is greater than the groundwater recharge. It creates a situation where the available groundwater is insufficient to support residents and businesses with drinking water. The high withdrawal of groundwater also creates a risk for saltwater intrusion to drinking water wells. The problem most commonly occurs during the summer when the groundwater recharge is low, but the population is high, due to tourism and summer residents.The purpose of this study was to investigate how local water supply in areas affected by water shortage can be solved as sustainable as possible. The work was divided into three parts where the first part comprised of a literature review on water systems in which four different options were investigated: artificial groundwater recharge, rainwater harvesting, desalination and water reuse.

Jämförelse av algoritmer för polygonisering utav volymetrisk data

Digitala spel har länge använt sig av terräng, det vanligaste sättet att lagra dessa terränger är med så kallade höjdkartor. Höjdkartor har en stor begränsning, de inte kan innehålla tunnlar.Denna rapport undersöker två alternativ till höjdkartor som arbetar med voxlar. Dessa två algoritmer är Marching Cubes (Lorensen & Cline, 1987) och Constrained Elastic Surface Nets (Gibson, 1998). Syftet med undersökningen är att evaluera dessa algoritmer med avseende på tidseffektivitet, minneseffektivitet och visuell korrekthet för att ta reda på vilken algoritm som öveträffar den andra med avseende på vilken aspekt.De utförda experimenten visade att Marching Cubes (Lorensen & Cline, 1987) var den mest tidseffektiva av de två, Constrained Elastic Surface Nets (Gibson, 1998) var mest minneseffektiv och Marching Cubes (Lorensen & Cline, 1987) var mest visuellt korrekt. Vidare forskning i ämnet skulle kunna göras på terränger som är för stora för enskilda modeller..

Naturlig haptisk kraftåterkoppling från volymdata

As the volumes are entering the world of computer graphics the pure volume visualisation becomes a more important tool in for example research and medical applications. But the advance in haptics --- force feedback from the computer --- is behind. In volume haptics no equal to the proxy method so popular in surface haptics has yet emerged. Some implementations of volume haptics even use surfaces as intermediate representations so that surface haptics can be used.The intention of this work was to create natural feeling haptic feedback from volumetric density data using pure volume haptics. The haptic algorithm would be implemented in Reachin API for the Reachin Desktop Display, together with other parts to build up a usable volume visualisation environment.To achieve the feeling of stiffness and friction dependent on tissue type, a proxy based method was developed.

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