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1141 Uppsatser om Light pollution - Sida 5 av 77

Canine S- and M/L- cone electroretinograms

Full-field flash electroretinography is an electrodiagnostic method used to examine the function of retinal cells. Light stimulation of the eye elicits electrical potentials in the retina. By aid of a corneal electrode and a reference electrode close to the back of the eye, the electrical potentials can be recorded and presented as an electroretinogram (ERG). ERGs driven by mainly one type of cones can be used to examine the function of a single cone class. In human beings, studies have shown the cone class sensitive to light of short wavelengths, the S-cones, to be more vulnerable to acquired damage than the other cone classes (Daley et al., 1987; Gouras et al., 1993; Greenstein et al., 1989). Dogs have two cone classes, S-cones, and M/L-cones (most sensitive to medium to long wavelengths).

Inte en glödlampa LED-armatur 35000 timmar till, Not a lightbulb LED luminaire 35000 hours more

Uppsatsen behandlar belysningsarmaturer inom LED-segmentet. Uppsatsen behandlar i synnerhet varför ljuskällan i LED-belysningsarmaturer oftast konstrueras så att ljuskällorna inte är utbytbara. Metoder som har använts i förstudien har varit; informationssökning, kvalitativa intervjuer, teknisk LED-modulsinventering samt konstruktionsundersökningar. Metoder som använts i produktutvecklingsfasen har varit; tekniska informationsstudier, Idéinventering genom visuell idégenerering, imageboards och skissprocess (att tänka med en penna). Syftet med projektet har varit att utveckla en LED-armatur med utbytbar ljuskälla. Projektets resultat blev en LED-golvarmatur med utbytbar ljuskälla. Ljuskällan som används i armaturen är enligt den unga branschfrivilliga standarden för LED-moduler, Zhaga..

Experimentella och teoretiska uträkningar för skruv- och bäddhållfasthet för takinfästningar mot stålstomme

Lättelement located in Örnskoldsvik AB is one of Sweden's leading companies in the development of building elements in the form of roofs, walls and floors made ??out of light beams. The company has clients from Lund to Kiruna, and from Norway. This means that the elements have high standards when they have to take many different loads from wind and snow due to such wide geographic variation.The roof elements are structured so that the main body is made of light beams with an I?profile.

Light spaces

Det här examensarbetet grundar sig i en gemensam fascination för hur ljus och mönster i samverkan kan förändra upplevelsen av ett rum eller skapa nya rumsligheter. Det handlar om att med traditionellt screentryck och tillägg av ljus hitta nya sätt att arbeta med och förnya användningen av mönstrad textil i offentlig miljö.Resultatet av arbetet är Light Spaces ? ett koncept för mönster och belysning i offentlig miljö där perspektiv förskjuts, linjer får en mening de inte först hade och nya rumsligheter skapas. I korridorer, öppna ytor och mötesplatser ger perspektiven i mönstren ? i samverkan med ljuset ? upphov till nya upplevelser och nya rum i rummen.

Light Explosion : rekonstruktion av en akrylarmatur

This report presents thesis of Liisa Kokkonen in collaboration with Muovikilpi Oy.The project?s goal is to find a new construction for an existing lamp made of acrylic. Form and design retains and the manufacturing occurs at Muovikilpi Oy. The project contains the new construction and manufacturing of the lamp and also a proposition for a set with floor and wall lamp.  The paper gives an outline of acrylic as material and how it reacts with light.

Handlingsplan för rening av dagvatten från hårt trafikerade gator i Örebro

The main purpose with the project has been to approximate the magnitude of the pollution transport from the actual road surfaces and to get an approximation of the possibility to collect the pollutants to reduce the load to the water and improve the water quality.The quantity of pollution transport from the most trafficated roads areas in Örebro city has been calculated. Roads whith a traffic exceeding 10 000 vehicle/day. The study has been done with the calculation tool StormTac. Through analysis of traffic loads and road surface, which together with a different kinds of parameters gives an approximation of the pollutant transport.The calculation has included some metals and other substances in the stormwater and has also included the present of suspended solids. Included the overall study, some smaller areas has also been calculated for the possibility to remove pollutants.The work also includes calculation for three different areas for stormwater treatment.

Möte i månsken : ett belysningsförslag för Fyristorg

The object of the thesis is to propose a new lighting plan for the square Fyristorg in Uppsala, and to describe the process which have led to it. It all started when I choosed the place together with the municipality of Uppsala. I have been doing research and analyzed how the place and it´s existing lighting works both during different times of the day and also in the evening. After researching the place and it´s existing lighting I´ve decided to put up the following goals fot the new lighting design. 1. The general light level of the place shall be experienced as higher than today. 2. The light level of the place shall be adapted to the light levels of surrounding places. 3. The lighting shall be free from glare. 4. The lighting shall be adapted to people passing by. 5.The lighting shall be adapted to the surrounding architecture. 6.

Geokemin inom osorterade cirklar : Analys av tungmetallers distribution inom jordprofiler tagna från Abiskoområdet, nordvästra Sverige

The Arctic region appears as a pristine remote environment, yet there is increasing evidence that it is greatly impacted by pollution such as lead (Pb) and mercury (Hg). In this environment deposition of Hg has increased threefold since the last industrial revolution. In this study five cryosolic soil profiles within non-sorted circles (NSC) in the Abisko region, northwest of Sweden, has been analyzed to improve our understanding regarding how pollutants are distributed within such type of soil. The soil samples have been analyzed with the use of X-ray fluorescence analysis (XRF), for the measurements of the total concentrations of e.g. lead (Pb) and zirconium (Zr).

Samspel mellan miljo?politik, innovation och teknikutveckling : Fallstudier om svenska avlopp, kylska?p och bilar

Within process or manufacturing industries, the production of goods and services or the products themselves may have negative side effects such as pollution. An important task for environmental policy is to control and limit these pollutions, for example via regulatory measures. Although, the efficiency of such measures vary greatly between different industries and an increasingly important task for environmental policy is then to encourage companies to engage in environmentally motivated innovation. Governments can utilize other measures than regulation to indirectly decrease pollution. This thesis aims to analyze such activities and how it affects the innovativeness of wastewater treatment, refrigeration and automobile manufacturing industries.

Vattenkvalitet och risker vid ändrat intag för vattenförsörjning i Västerås

Water is the most essential resource for life. In cases where drinking water is processed from surface water it is important to ensure the raw water is of good quality, and is suitable for processing through the water treatment plant.The drinking water for Västerås is sourced from Västeråsfjärden, in the western side of Lake Mälaren. The city itself is home to marinas, ports, a wastewater treatment plant, the Svartån outlet, sewage pumping stations and stormwater outlets. Because of the negative effects these activities have on surface water quality, Mälarenergi AB is interested in relocating the raw water intake point to Granfjärden, 10 km east of Västeråsfjärden. At Granfjärden the intake point would be less exposed to the activities in Västerås, and could be placed at a greater depth, resulting in better water quality.In this Master?s thesis the water quality and the pollution risks at Västeråsfjärden and Granfjärden sites are compared.

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.

Value stream mapping i praktiken : En fallstudie på Light My Fire

Titel: Value stream mapping in practice ? A case study at Light MyFireAuthors: David Rydman and Tomas ÖnnemarMentor: Veronica Ülgen SvenssonExaminer: Åsa GustafssonBackground: Companies push their prices in today's markets to be competitive, which means that companies need to find ways to reduce costs while maintaining profits. (Cudney, 2009) According to Bergman and Klefsjö 2007, the basic rule of quality improvement says "there is always a way to achieve higher quality at a lower cost". One way is to improve a company's processes to get a more efficient flow and improvements that may cut costs. (Bergman & Klefsjö, 2007) Why it's important to look at the processes are that they often contain waste that can be eliminated.

Tillämpning av GIS-analyser i MKB

The reason for performing an Environmental Impact Assessment (EIA) is to incorporate environmental concern in different kinds of plans and projects. The purpose of such an assessment is to identify and describe direct, indirect and cumulative environmental impacts.Geographical Information System (GIS) is a tool that can be used to combine spatial extension of both sensitive areas and different environmental impacts in a quick and easy way. Because of that, descriptions of environmental impacts and motivation of different standpoints on a specific issue can be more correct and easier to make if GIS is used as a tool.Hence, GIS can contribute to improve the quality of Environmental Impact Assessments. If the benefits of using GIS are to out weight the costs, geographical information of satisfactory detail, actuality and accuracy need to be available at reasonable prices.In this paper, case studies are carried out for three different geographical analyses to investigate the use of GIS as a tool in EIA. From these case studies, more general conclusions about the benefits and limitations of using GIS for Environmental Impact Assessments are also drawn.

Utfackningsvägg av lättbetongblock i passivhus

AbstractThis report intends through a case study to investigate if lightweight concrete isappropriate as main material in the outer wall of a seven storey residential building.A technical design is carried out in accordance with the definitions and requirementsfor passive houses, given by FEBY?s1 ?Demand specification for passive houses?.A literature review is also carried out for a comparison between regular bolt wall andlight weight concrete wall, with a focus on the safety of moisture.The lightweight concrete block used in the report is as a celblock produced by thecompany H+H Sweden AB.The methods used have resulted in compliance with requirements andrecommendations from authorities. Calculations of energy, noise and moisture riskassessment has been carried out.The work has resulted in the conclusion that the lightweight concrete itself is notable to isolate in the extent necessary to obtain chosen U-value of 0,1 W/m2 ° C,without getting to thick. Therefore additional insulation is needed. There are fewrelevant reference objects built with only light weight concrete.

Biochar as soil amendment in flow-through planters - for increased treatment of zinc roof runoff

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

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