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161 Uppsatser om Optical filters - Sida 1 av 11

Simulering av filtrerade skärmfärger

This report present a working model for simulation of what happens to colors displayed on screens when they are observed through Optical filters. The results of the model can be used to visually, on one screen, simulate another screen with an applied optical filter. The model can also produce CIE color difference values for the simulated screen colors. The model is data driven and requires spectral measurements for at least the screen to be simulated and the physical filters that will be used. The model is divided into three separate modules or steps where each of the modules can be easily replaced by alternative implementations or solutions.

Double integrating spheres: A method for assessment of optical properties of biological tissues

The determination of the optical properties of biological tissue is an important issue in laser medicine. The optical properties define the tissue´s absorption and scattering behaviour, and can be expressed by quantities such as the albedo, the optical thickness and the anisotropy coefficient. During this project, a measurement system for the determination of the optical properties was built up. The system consists of a double integrating sphere set-up to perform the necessary reflection and transmission measurements, and a computer algorithm to calculate the optical properties from the measured data. This algorithm is called Inverse Adding Doubling method, and is based on a one-dimensional transport model.

Optiska egenskapers påverkanav möjligheten att trycka eftermålvärden i ISO 12647-2.

This thesis investigates how the optical properties of paperboard influences printing with targets in ISO 12647-2. The targets for optical properties in ISO 12647-2 are defined for paperboard without optical brightening agents and fluorescent brightening agents wich makes it difficult to reach the targets when printing paperboard containing these agents.Seven different types of paperboard, some with and some without the agents, have been printed and instrumentally andvisually measured to see if there is any deviation from the standard targets and if it shows visually.The result shows that paperboard containing optical brightening agents and fluorescent brightening agents can print with targets in ISO 12647-2 but in many measurments the difference between the types of paperboard were to small to assess. The differences between the types of paperboard in the instrumental measurements did not fully correspond with the waythe panel appraised them visually..

Filter = censur? En enkätundersökning om bibliotekariers rätt att begränsa information med hjälp av datorfilter.

The main purpose of this paper is to examine librarian's opinion of computer filters, to bring order in the debate on these filters and also to encourage future debate on this subject. The main problem is whether librarians themselves think they have the right to limit the public access to information on the Internet by using computer filters. We will also see how many public libraries are using filters, why they have chosen to use or not to use them, what is the librarians' opinion of filters, what rules exist regarding the use of the Internet, and finally if it is legal to use filter programs in public libraries. We have also included a short report on what filters are and how they work. This paper deals only with Swedish conditions on a number of public libraries.

Analys och modifiering av digital filteralgoritm för gassensor

AbstractThis work was assigned by a technological company that manufactures gas detectors in which the sensor signal is processed using digital filters. These filters have been developed by a consultancy firm which converted previously used analog filters to digital filters. The purpose of this work has been to analyse inadequate, and sometimes erroneous, documentation from the project in order to provide the company with know-how and tools for further improvement of their products. The work has been done using the simulation software COMSOL which was bought solely for the project. Analysis showed serious flaws as well as pure errors in the consultant?s documentation.

Asymptotiska egenskaper hos vissa kombinatoriska strukturer

In an attempt to develop a more cost-efficient material for solar   energy applications, nano-particles of nickel oxide composite in a silikatmatris manufactured with solar gelmethod and studied structurally by electron microscopy. Furthermore, the thin film optical properties characterized by Variable. Angel Spectroscopic Ellipsometry. Sol gelfilms suitability as a selective absorber surface is also analyzed by optical modeling..

Design and Analysis of an All-optical Free-space Communication Link

Free Space Optics (FSO) has received a great deal of attention lately both in the military and civilian information society due to its potentially high capacity, rapid deployment, portability and high security from deception and jamming. The main issue is that severe weather can have a detrimental impact on the performance, which may result in an inadequate availability. This report contains a feasibility study for an all-optical free-space link intended for short-range communication (200-500 m). Laboratory tests have been performed to evaluate the link design. Field tests were made to investigate availability and error performance under the influence of different weather conditions.

Prestanda på luftfilter : En jämförelse mellan olika filter till bil

This reports goal is the give BSR AB more information that's useful towards their customers in marketing of their products.It involves tests of different air filters designed for cars and 3D-modelling of Opti-Flow systems. The three models thats being tested is SAAB (93SS), VAG (1.8T) and Volvo (S60). To every brand there are three different models. A orginal- , sport- and an open cone air filter (Opti-Flow).The results indicate that the open Opti-Flow filter has better performance compared to the other cased filters. The sport filters for SAAB and Volvo has better performance then the original filter.

Tillförsel av använda fosforfilter påverkar inte tillväxten eller fosforupptaget hos korn

The eutrophication of inshore seas, lakes and watercourses is mainly due to leaching of nitrogen and phosphorus (P) from agriculture. Many efforts are made to reduce the lea-kage of phosphorus in Sweden and the Baltic Sea countries. Phosphorus is also a finite resource and the mining of good quality raw material gets more and more difficult. Se-dimentation dams in combination with filters is one relatively new method to separate P from run-off and drainage water from agricultural land. This study was a part of an IVL Swedish Environmental Research Institute?s project which tests the capacity and func-tion for separation of phosphorus in four phosphorus filters.

Optisk karakterisering av tunna SiO2/NiO-filmer syntetiserade med en sol-gelmetod

In an attempt to develop a more cost-efficient material for solar   energy applications, nano-particles of nickel oxide composite in a silikatmatris manufactured with solar gelmethod and studied structurally by electron microscopy. Furthermore, the thin film optical properties characterized by Variable. Angel Spectroscopic Ellipsometry. Sol gelfilms suitability as a selective absorber surface is also analyzed by optical modeling..

Optisk sortering av matavfall : en jämförelse med en minskning av svinnet

The purpose of this study is to compare the energy related and environmental consequences of implementing optical sorting as a means of waste collection with those of reducing food waste. In addition to studying the possibility of implementing optical sorting in downtown Stockholm, the yielded amounts of energy from waste collection and reduced wastage will be calculated. This is done by way of literature reviews and interviews. The amount of energy that can be generated through optical sorting and biogas production via anaerobic digestion in downtown Stockholm is 29-44 TJ/year, compared to 118 TJ/year saved by completely eliminating food waste. The generated biogas can replace fossil fuels, but the required food waste contributes to increased greenhouse gas emissions as well as reduced bio diversity and eutrophication during the wasted food?s lifecycle.

Igensättning av långsamfilter i Östby vattenverk i Kramfors : studie av påverkande faktorer

Östby waterworks in the community of Kramfors has since 2003 had problems of fast clogging of the slow sand filters. As the clogging appears more often, they must be cleaned more frequently which has made the drinking water preparation difficult. Wintertime it has sometimes been impossible to clean the filters which has led to their closing and this has influenced the water quality negatively.The waterworks is a surface waterworks which takes its raw water from the lake Sjöbysjön. The water is flocculated and filtered in a contact filter with the flocculent EKOFLOCK 91. Thereafter it is alkalinized before it reaches the outdoors placed slow sand filters.

Optimerade material för optiska komponenter i koncentrerande solfångare

The energy consumption continues to increase as the use of electronics and energy consuming equipment increases. The use of fossil fuels has to be phased out for this to be sustainable in the long run while the use of renewable energy continues to increase. A renewable energy source is solar energy but the production of heat and electricity are today very expensive compared to other energy sources and an important task for the solar energy market to grow is therefore to minimize the production cost of the solar collectors while increasing its efficiency to produce heat and/or electricity. One way to convert solar energy into heat is by using solar collectors and electricity can be produced by utilizing the produced heat, or by applying solar cells.This thesis aims to recommend a reflective material for the next generation solar collectors from Absolicon and to recommend a commercially available coating for the receiver tube of the solar collector. A market study has been carried out to investigate the cost-related aspects along with the optical and durable aspects for the optical material of the solar collector.

Detektering från prickskyttar från helikoptrar : elektrooptiska sensorer i VMS

Sverige är för tillfället operativa med Helikopter 16 - Black Hawk i Afghanistan. Uppgiften som löses i Afghanistan är främre och taktisk sjuktransport (MEDEVAC).Detta arbete handlar om hur befintliga VMS-system i helikoptrar kan kompletteras i syfte att möta ett föreliggande prickskyttehot vid lösande av främre MEDEVAC i ett insatsområde som miljömässigt liknar Afghanistan. I arbetet analyseras möjliga tekniker utifrån aspekter från ett konstruerat scenario där helikopterbesättningarnas uppgift, insatsmiljö samt hotbild beskrivs.Resultatet visar på att MEDEVAC-helikoptrar kan utrustas med sensor-gimbaler där olika sensorer kan kombineras, vilket möjliggör spaning i 360°. Detta bidrar till den militära nyttan då helikopterpersonalens lösande av uppgift effektiviseras, chansen till överlevnad ökar samtidigt som personal och patienter kan känna sig tryggare..

Gravitationslinser

Gravitational lenses are unlike ordinary optical lenses, a phenomenon corrupting our optical view of the cosmos. When we look out intospace we see celestial bodies lying with astronomical distance from Earth. There is no guarantee that what we see out there in space is actually there where we are observing it, and it may be that we see multiple images of the same star! Studies have shown that thenumber of distorted images of an n-mass (n > 1) plane lens can not exceed 5(n -1) for lighter lenses or 5n for more massive lens. This mathematical thesis covers gravitational lensing and their properties that distort light rays coming towards us from distant celestial bodies. In addition of gravitational lensing, its properties and the proof of the maximum number of distorted images, a bigger part of this work even cover two very interesting mathematical tools - the so-called Schwarz function and Bezout theorem..

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