New improved model was developed to calculate the absorption and refractive-index spectra in the band-edge region for all the important compound semiconductors. An accurate absorption model including Coulomb interaction and Urbach-broadened band edge has been demonstrated for direct bandgap semiconductors. We have developed a accurate model in which a piecewise linear approximation is used for the shape of the absorption spectrum. We also propose a steep-edged compound Lorentzian line-shape function (SCL-LSF) for modeling the Urbach tail, and the line broadening of exciton absorptions. The results of applying this fitting procedure to the absorption spectra of GaAs, InP and InAs are presented, and a consistent set of band parameters are extracted. The analytical absorption model is suitable for a complete closed-form Kramers-Kronig transform of the absorption spectrum to obtain the refractive index spectrum. A band-to-band Coulomb interaction model for the refractive index spectra is presented of AlxGa1-xAs for 0 < x < 0.412, and In0.53Ga0.47As ternary semiconductors at photon energies near and above the band gap. An accurate absorption model is used to calculate the contribution on the refractive index near band-edge region through a complete closed-form Kramers-Kronig transform. By including a single oscillator Sellmeier model for the high-energy absorption spectrum, closed-form expressions are obtained for the band-edge region refractive index. Both spectra are fully described in terms of a finite set of parameters that can be interpolated for all the important compound semiconductors. The refractive index spectra are extended beyond the band-gap energy and are in excellent agreement with the available experimental data. Our new model makes accurate modeling possible for devices such as electroabsorption and electrorefraction modulators.

<p>In this thesis, I examine the performance of a sample of ten Swedish-based internationally diversified mutual funds managed by one of the largest commercial banks in the Nordic region.</p><p>The investigation cover a time span between 2000 and 2005 divided into two sets, 2000-2002 and 2003-2005. To measure the performance of the funds, I will utilize the Jensen’s index.</p><p>The results shows that there is no empirical evidence which indicates that managers seize superior stock selection skills when investing locally compared with investing on different markets for the selected funds. It does on the other hand shows that two out of the seven funds increases the beta towards the market when the market goes up. Finally, this thesis shows that inclusion of emerging markets creates further possibilities for diversification in a portfolio due to more developed markets tends to have high level of integration and move together.</p>

Diss. (sammanfattning) Jönköping : Hälsohögskolan, 2009. / Härtill 4 uppsatser.

Reproduction de : Thèse de Doctorat en Lettres : Littératures francophones : Cergy-Pontoise : 2008. / Titre provenant de l'écran titre. Bibliogr. p.452-479. Index.

Diss. (sammanfattning) Göteborg : Univ. , 2008. / Härtill 4 uppsatser.

Purpose The purpose of this thesis is to investigate the challenges related to measuring sustainability within the textile industry. The study concentrates on the industry-specific self-assessment tool Higg Index and strives to point out the challenges of using the tool. In order to find a solution for the measurement problems, the purpose is to investigate how the current, non-financial Higg Index indicators could be translated into financial ones. Method The nature of the research is qualitative and it comprises of two parts: structured interviews and a desk research. Methodological triangulation is used in order to gain data on different levels – both from the users of the Higg Index and from literature. The data collection has been conducted through four structured interviews with the users of the Higg Index. The second part of the thesis is concerned with converting the non-financial indicators of the Higg Index into financial indicators using the balanced scorecard approach. Conclusion Measuring sustainability has been considered difficult due to the qualitative nature of the measured matters. Higg Index has proven to be a comprehensive self-assessment tool for organizations in the textile industry to use. It is considered to enhance communication, increase information sharing, and facilitate benchmarking. However, in order to develop the tool and make it more attractive to non-users, there are opportunities for improvement. These opportunities include adding verification and making the data collection easier. Transforming non-financial indicators of the Higg Index into financial indicators can simplify the data collection and increase the attractiveness of sustainability performance measurement tools.

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The earth surface is monitored periodically by numerous satellite sensors which have different spectral response functions, image acquisition heights, atmosphere correction schemes, overpass times, and sun/view angle geometries. Temporal and spatial variations of land surface properties, such as vegetation index, Leaf Area Index (LAI), land surface temperature, and soil moisture, have been provided by long-term time series of various remote sensing datasets. Inter-sensor translation equations are required to build long-term time series by the combination of multiple sensors from historical to advanced and new satellite datasets. In the first chapter, inter-sensor translation equations of band reflectances and two vegetation indices (e.g. Normalized Difference Vegetation Index (NDVI) and Enhanced Vegetation Index (EVI)) were derived using linear regression equations relative to Moderate Resolution Imaging Spectroradiometer (MODIS) values. The consistency and validation of inter-sensor transforms were investigated through statistical student's t-test and the root mean square error (RMSE).In the second chapter, cross-sensor extension of EVI and a 2-band EVI (without the blue band; EVI2) were investigated based on the continuity of both EVI's. Sensor specific red-blue coherencies were examined for the possibility of the EVI and EVI2 extension from MODIS sensor. The EVI continuity to MODIS was particularly problematic for the Visible Infrared Imager / Radiometer Suite (VIIRS) and the Sea-viewing Wide Field-of-view Sensor (SeaWiFS) that have dissimilar blue bands from that of MODIS. The cross-sensor extension and compatibility of EVI2 were improved and provided the possibility to be lengthened to the Advanced Very High Resolution Radiometer (AVHRR) using its translation equation.Finally, we evaluated the use of sensor-specific EVI and NDVI data sets, using a time sequence of Hyperion images over Amazon rainforest in Tapajos National Forest, Brazil for the 2001 and 2002 dry seasons. We computed NDVI, EVI, and EVI2 with the convolution data of different global monitoring and high temporal resolution sensor systems (AVHRR, MODIS, VIIRS, SPOT-VGT, and SeaWiFS) from Hyperion, and evaluated their spectral deviations and continuity in the characterization of tropical forest phenology. Our analyses show that EVI2 maintains the desirable properties of increased sensitivity in high biomass forests across all sensor systems evaluated.

Two strategies to reduce impact of heat stress on high producing dairy cows were examined. The first was to recalculate the temperature-humidity index (THI) using high producing dairy cows under diurnal summer conditions. This re-evaluation confirmed that current THI values underestimate the severity of heat stress levels. Therefore, cooling of dairy cattle during warm summer months should begin at a THI of 68. Previously, a THI equal to or greater than 72 has been used to define onset of heat stress. This study demonstrated that a THI greater than or equal to 68 is sufficient to increase body heat storage, respiration rate, skin evaporative heat loss, declines in feed intake and milk yield. A second objective involved three studies carried out to evaluate use of niacin in dairy cow rations to improve evaporative heat loss and resistance to heat stress. Niacin is known to cause intense vasodilation in human and lab species. We hypothesized that increasing vasodilation would improve evaporative heat loss in dairy cows. In the first niacin study, supplementation of lactating dairy cows with an encapsulated rumen by-pass form of niacin (NIASHURE™; Balchem Corporation, New Hampton, NY) at a dose of 12 g/d proved effective in alleviating some affects of heat stress during mild thermal stress. We hypothesized that encapsulated niacin would induce vasodilation effects documented in humans and lab animals increasing evaporative heat loss. Past research demonstrated that the possible mechanism for vasodilation affects seen by niacin were most likely due to prostaglandin D secretions. Niacin may act through increased prostaglandin D and E production and secretion by Langerhans cells which then act upon vascular endothelial prostaglandin D receptors to increase vasodilation. No studies have evaluated impact of encapsulated niacin on milk yield and composition during periods of thermal stress under commercial dairy conditions. The objective of the last study was to examine the effects of encapsulated niacin during heat stress on milk production and composition as well as core body temperatures under commercial conditions.