Optical Characterization and Optimization of Display Components : Some Applications to Liquid-Crystal-Based and Electrochromics-Based Devices

This dissertation is focused on theoretical and experimental studies of optical properties of materials and multilayer structures composing liquid crystal displays (LCDs) and electrochromic (EC) devices. By applying spectroscopic ellipsometry, we have determined the optical constants of thin films of electrochromic tungsten oxide (WOx) and nickel oxide (NiOy), the films’ thickness and roughness. These films, which were obtained at spattering conditions possess high transmittance that is important for achieving good visibility and high contrast in an EC device. Another application of the general spectroscopic ellipsometry relates to the study of a photo-alignment layer of a mixture of azo-dyes SD-1 and SDA-2. We have found the optical constants of this mixture before and after illuminating it by polarized UV light. The results obtained confirm the diffusion model to explain the formation of the photo-induced order in azo-dye films. We have developed new techniques for fast characterization of twisted nematic LC cells in transmissive and reflective modes. Our techniques are based on the characteristics functions that we have introduced for determination of parameters of non-uniform birefringent media. These characteristic functions are found by simple procedures and can be utilised for simultaneous determination of retardation, its wavelength dispersion, and twist angle, as well as for solving associated optimization problems. Cholesteric LCD that possesses some unique properties, such as bistability and good selective scattering, however, has a disadvantage – relatively high driving voltage (tens of volts). The way we propose to reduce the driving voltage consists of applying a stack of thin (~1µm) LC layers. We have studied the ability of a layer of a surface stabilized ferroelectric liquid crystal coupled with several retardation plates for birefringent color generation. We have demonstrated that in order to accomplish good color characteristics and high brightness of the display, one or two retardation plates are sufficient.

Financial time series analysis : Chaos and neurodynamics approach

This work aims at combining the Chaos theory postulates and Artificial Neural Networks classification and predictive capability, in the field of financial time series prediction. Chaos theory, provides valuable qualitative and quantitative tools to decide on the predictability of a chaotic system. Quantitative measurements based on Chaos theory, are used, to decide a-priori whether a time series, or a portion of a time series is predictable, while Chaos theory based qualitative tools are used to provide further observations and analysis on the predictability, in cases where measurements provide negative answers. Phase space reconstruction is achieved by time delay embedding resulting in multiple embedded vectors. The cognitive approach suggested, is inspired by the capability of some chartists to predict the direction of an index by looking at the price time series. Thus, in this work, the calculation of the embedding dimension and the separation, in Takens‘ embedding theorem for phase space reconstruction, is not limited to False Nearest Neighbor, Differential Entropy or other specific method, rather, this work is interested in all embedding dimensions and separations that are regarded as different ways of looking at a time series by different chartists, based on their expectations. Prior to the prediction, the embedded vectors of the phase space are classified with Fuzzy-ART, then, for each class a back propagation Neural Network is trained to predict the last element of each vector, whereas all previous elements of a vector are used as features.

Historical Consciousness, Historical Media, and History Education

This thesis by publication contains an introductory summary chapter and three papers. The first paper presents a study of how the concept of historical consciousness has been defined, applied, and justified in Swedish history didactical research. It finds that there is consensus regarding the definition of what a historical consciousness is, but that there is variation in how the concept is applied. It is suggested that this variation makes historical con­sciousness a complex and vague concept.      The second paper uses the results presented in the first paper as a point of departure and from thence argues for a broadened understanding of the concept of historical consciousness that incorporates its definition, applica­tion, development, and significance. The study includes research about his­torical consciousness primarily from Sweden, the UK, the USA and Canada. The paper presents a typology of historical consciousness and argues that level of contextualisation is what distinguishes different types of historical consciousnesses and that an ability to contextualise is also what makes his­torical consciousness an important concept for identity constitution and morality.      The third paper proposes a methodological framework of historical con­sciousness based on the theory of historical consciosusness presented in the second paper. It presents arguments for why the framework of historical consciousness proposed can be useful for the analysis of historical media and it discusses how aspects of the framework can be applied in analysis. It then presents a textbook analysis that has been performed according to the stipulated framework and discusses its results regarding how textbooks can be used to analyse historical consciousness and its development.

Mångfald - Från ord till handling : En kvalitativ studie om HRs strategiska arbete med mångfald

Denna studie grundar sig i ett uppdrag från Trafikverket med avsikten att undersöka hur enmångfaldsstrategi kan få ökad effekt i organisationen. Utgångspunkten för denna studie är attdet tycks krävas mer forskning kring hur HR strategiskt kan arbeta med mångfaldsfrågor ochintegrera dem i organisationens alla delar. Syftet med denna studie är således att identifiera hurHR strategiskt kan arbeta med mångfaldsfrågor. Vidare är syftet att visa hur ett strategiskamångfaldsarbete kan bli mer effektivt.Teorier som belyser begreppet mångfald, effekterna av mångfald, strategi, Human ResourceManagement och Strategic Human Resource management kan ses ligga till grund för ettframgångsrikt HRM-arbete med mångfald. Ledarskap, kommunikation, kunskap och att se tillorganisationskulturen belyser teorin som viktiga komponenter för att ett strategiskt arbete skabli mer effektivt och ge effekt i organisationen.Studien bygger på en deduktiv ansats och en kvalitativ metod har genomförts utifrån treindividuella intervjuer och två fokusgrupper. De individuella intervjuernas syfte var att belysaorganisationens nutida arbete med mångfald, framtida perspektiv för hur ett strategisktmångfaldsarbete kan utformas och en målbild för vad arbetet ska resultera i. Den enafokusgruppen bestod av medarbetare från HR från olika regionkontor i landet och hade somsyfte att klargöra hur HR strategiskt kan arbeta med mångfald. Den andra fokusgruppen bestodav chefer från olika regionkontor i landet och hade som syfte att belysa chefers roll och vad deeftersöker i ett strategiskt mångfaldsarbete.Resultatet från intervjuerna har analyserats utifrån den teoretiska referensramen och i dennastudie har vi kommit fram till och identifierat flera betydelsefulla faktorer som för HR är viktigai utformandet av en mångfaldsstrategi. Det är viktigt att definiera begreppet mångfald, klargöraansvarsfrågan, visa på varför organisationen bör arbeta med månglad och kommuniceraeffekterna. Vidare är det viktigt att koppla mångfaldsstrategin till övriga HRM-aktiviteter ochorganisationens övriga strategier och mål för att det strategiska arbetet ska ge effekt. Kunskapom mångfald och att se arbetet som ett förändringsarbete där ledningen utgör en viktig roll harvisat sig vara väsentliga faktorer för att arbetet ska få värde i organisationen.