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2110 Uppsatser om Optical transfer function - Sida 1 av 141

Transferfunktionsmodeller modellering och prognoser av Sjötransportindex

We have by Statistics Sweden (SCB) been given the task of using different dynamic regression models in order to forecast service price index for sea transport. The aim is to see whether these models provide better forecasts than those previously used. This essay aim to identify, estimate and evaluate the selected prediction models. Through our data material we were given access to 28 sightings of sea transport index during the period of 2004 q1 to 2010 q4. We have chosen to evaluate three different transfer function models, one ARIMA model and one naive forecasting model. The input variables we decided to test in our transfer function models were the price of petroleum products, the port activity in Swedish ports and the lending rate of Swedish Central bank. The results of our study suggest that transfer function models generally provide better models than the ARIMA model and the naive forecast model.

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.

Röntgenbilder: en studie av bildkvalitet inom medicinsk
röntgendiagnostik: en matematisk metod för jämförelse
mellan olika röntgenapparater

I sjukvården världen över tas dagligen tusentals röntgenbilder. Användningsområdena är många, men i de flesta fall är syftet att i något avseende avgöra patientens hälsa. Bilderna utvärderas av läkare för att patienten ska få rätt diagnos. För att läkaren ska kunna göra en korrekt bedömning av bilden och därmed ge patienten den behandling som situationen kräver måste bilden vara rättvisande och vara av sådan kvalitet att alla viktiga detaljer går att urskilja. Bildkvalitet är ett ganska diffust begrepp och ofta används subjektiva bedömningsmetoder för att bestämma ifall en bild är bra eller dålig.

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..

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..

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.

Sveplaserns användning till inventering/befästning/kontroll av vägmarkering

The thesis mission is to investigate whether the swiveling laser that Vectura (former Vägverket Konsult) has in use to measure the road areas and straddle measuring can be used to detect differences in the reflective road markings function. This is to increase use of the swiveling laser and get rid of the manual measurements performed today.Currently, the measurement of road markings reflective function is performed with both mobile and handheld measuring instruments. The purpose of this thesis is to develop better methods for determination of road markings? reflective function, in order to facilitate the description and suggestions for improvements of the maintenance of road markings reflective function.The questions that the thesis has been to start with are:Can the swiveling laser detect differences in longitudinal and transverse road markings reflective function?The accuracy of measurement has been sweeping the laser over the reference instrument (LTL-2000)Is it necessary with a conversion factor for swiveling laser data against the reference instrument data?To answer the question 2 and 3, there has been a field work in Värnamo where a road stretch with longitudinal road markings and zebra crossing (transverse road markings) has been investigated with a swiveling laser and LTL-2000.The formulas and calculations contained in the thesis are drawn from scientific reports that are produced by VTI in Linköping. The same formula that was used to calculate the optical measurement data was also used for the swiveling laser data.

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.

Anställningsskydd vid verksamhetsövergång : Vilka rättigheter och skyldigheter övergår?

Transfer of undertaking or business is a complex fact. It requires many aspects to be takeninto consideration. For there to be a transfer of undertaking or business, it has to be a stableeconomic entity that after transfer has retained its identity. The provisions regarding transferof undertaking or business is found in the transfer of undertaking or business directive,6 b § LAS and 28 § MBL.An employee?s employment is automatically transferred to the transferee.

Inkongruenta styrmodeller: En fallstudie av reparation och underhåll i ett industriföretag

In theory, the management control of maintenance functions is described as problematic due to the nature of the work performed in the unit. The purpose of this thesis is to examine these predicted problems in practice. Further,the thesis aims at identifying how these control problems may affect the relationships between the maintenance department and its internal customers. A case study has been conducted in one of Sweden?s largest industrial companies to investigate the said control problems in practice.

?That´s something we people have create in our mind, because we have booring?? : En studie om språklig transfer i elevers skrivande

Syftet med denna uppsats var att studera svenskans påverkan på inlärning av och skriftproduktion i engelska bland elever i svensk grundskolas senare år och gymnasium. Studien genomfördes genom studier av elevtexter på engelska, där mellanspråkliga fel beroende på negativ transfer från svenska till engelska analyserats och kategoriserats. Resultaten visar att negativ transfer främst förekommer i grammatiska mönster som preposition + att-satser, bisatsordföljd, passivkonstruktion och i satser utan korrelat samt vokabulära strukturer som partikelverb och idiomatiska uttryck..

Erfarenhetsöverföring vid svenska utlandsstyrkan : Vilka faktorer påverkar och hur?

The purpose of this paper is to identify the factors affecting the experience transfer at the rotation of the missions. This is to identify the respective influences are inhibitory factor, which contributes to a less efficient transfer, or if it contributes to a more efficient handover. The method used for the production of this paper is a qualitative case study of squad leaders who have done service in Kosovo or Afghanistan. Through interviews with focus on the transfer of experience, both on individual and organizational level, the factors that affect are being identified. The model used is expressed in a general perspective, where each factor is categorized as inhibitory or contributing to success, and if it appears on an organizational or individual level.

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.

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