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Debris discs are often modelled assuming compact dust grains, but more and more evidence for the presence of porous grains is found. We aim at quantifying the systematic errors introduced when modelling debris discs composed of porous dust with a disc model assuming spherical, compact grains. We calculate the optical dust properties derived via the fast, but simple effective medium theory. The theoretical lower boundary of the size distribution - the so-called 'blowout size' - is compared in the cases of compact and porous grains. Finally, we simulate observations of hypothetical debris discs with different porosities and feed them into a fitting procedure using only compact grains. The deviations of the results for compact grains from the original model based on porous grains are analysed. We find that the blowout size increases with increasing grain porosity up to a factor of 2. An analytical approximation function for the blowout size as a function of porosity and stellar luminosity is derived. The analysis of the geometrical disc set-up, when constrained by radial profiles, is barely affected by the porosity. However, the determined minimum grain size and the slope of the grain size distribution derived using compact grains are significantly overestimated. Thus, the unexpectedly high ratio of minimum grain size to blowout size found by previous studies using compact grains can be partially described by dust grain porosity, although the effect is not strong enough to completely explain the trend.

We present the first results from an ongoing survey to characterize the circumgalactic medium (CGM) of massive high-redshift galaxies detected as submillimeter galaxies (SMGs). We constructed a parent sample of 163 SMGQSO pairs with separations less than similar to 36" by cross-matching far-infrared-selected galaxies from Herschel with spectroscopically confirmed QSOs. The Herschel sources were selected to match the properties of the SMGs. We determined the sub-arcsecond positions of six Herschel sources with the Very Large Array and obtained secure redshift identification for three of those with near-infrared spectroscopy. The QSO sightlines probe transverse proper distances of 112, 157, and 198. kpc at foreground redshifts of 2.043, 2.515, and 2.184, respectively, which are comparable to the virial radius of the similar to 10(13) M circle dot halos expected to host SMGs. High-quality absorption-line spectroscopy of the QSOs reveals systematically strong H I Ly alpha absorption around all three SMGs, with rest-frame equivalent widths of similar to 2-3 A. However, none of the three absorbers exhibit compelling evidence for optically thick H I gas or metal absorption, in contrast to the dominance of strong neutral absorbers in the CGM of luminous z similar to 2 QSOs. The low covering factor of optically thick H I gas around SMGs tentatively indicates that SMGs may not have as prominent cool gas reservoirs in their halos as the coeval QSOs and that they may inhabit less massive halos than previously thought.

Masters in Public Administration - MPA / The focus of this research is evaluating the impact of the National Directorate of Employment policy on selected agro - chemical small and medium enterprises in Akure, Nigeria. The importance of small and medium business development cannot be overemphasized because it plays a significant role in developed nation’s economy of the world. The development of small business has been variously referred to as a “source of employment generation”. Poverty and unemployment is a big challenge to the government of Nigeria and there is continual increase in the unemployment rate, which is alarming and has resulted in socio-political and economic crises. There are efforts by government to tackle this scourge. In order to fill this gap, government established various institutions with policies and programmes to tackle unemployment and poverty. However, the problem still persists. The government of Nigeria established the National Directorate of Employment programme, which main objective is designed to cater for unemployed youth and jobless people across the country. This study evaluated the impact of the National Directorate of Employment policy on selected agro chemical - sector in order to assess its influence in job creation and poverty reduction in Akure, Ondo State Nigeria. Within the investigation, my research focused at the appropriate legislation and policies of the National Directorate of Employment programme. The study comprises of mixed methods (qualitative and quantitative approach) using both primary and secondary data.

This study was a research on the effects of the change in the tax system on small medium sized enterprises. Its focus was in Swaziland. It concludes by giving recommendations on how the tax system can be improved in view of what have succeeded in other countries with an almost similar economy. It also recommends more research in this field.

Massive young stars dynamically modify their surroundings, altering their stellar nurseries and the gas that exists between stars. With my research, I assess the modification of the Galactic magnetic field within HII regions and stellar bubbles associated with OB stars. Because HII regions are plasmas, magnetic fields should be important to the dynamics of the region. Understanding how the magnetic field is modified in these structures is critical for inputs to simulations and for assessing stellar feedback. To obtain information on the properties of the magnetic field, I measure the Faraday rotation of linearly polarized radio waves that pass through the plasma of the HII region. In this thesis, I present results of Faraday rotation studies of two Galactic \HII regions. The first is the Rosette Nebula (l = 206 deg, b = -1.2 deg), and the second is IC 1805 (l = 135 deg, b = 0.9 deg), which is associated with the W4 Superbubble. I measure positive rotation measure (RM) values in excess of +40 to +1200 rad m^-2 due to the shell of the Rosette nebula and a background RM of +147 rad m^-2 due to the general interstellar medium in this area of the Galactic plane. In the area of IC 1805, I measure negative RM values between +600 and --800 rad m^-2 due to the HII region. The sign of the RM across each HII region is consistent with the expected polarity of the large-scale Galactic magnetic field that follows the Perseus spiral arm in the clockwise direction, as suggested by Van Eck et al. (2011, ApJ, 728, 14). I find that the Rosette Nebula and IC 1805 constitute a "Faraday rotation anomaly", or a region of increased RM relative to the general Galactic background value. Although the RM observed on lines of sight through the region vary substantially, the |RM| due to the nebula is commonly 100 -- 1000 rad m^-2. In spite of this, the observed RMs are not as large as simple, analytic models of magnetic field amplification in HII regions (such as by magnetic flux conservation in a swept-up shell) might indicate. This suggests that the Galactic field is not increased by a substantial factor within the ionized gas in an HII region. Finally, these results show intriguing indications that some of the largest values of |RM| occur for lines of sight that pass outside the fully ionized shell of the IC 1805 HII region, but pass through the Photodissociation Region (PDR) associated with IC 1805.

The purpose of this study is to develop a better understanding of strategic paths to knowledge management in small and medium-sized hotels. This thesis has formulated a path knowledge concept and developed a PathFinder model. The formulation of the path knowledge concept and the development of the PathFinder model are based on an empirical investigation through the conduct of thirteen face-to-face in-depth interviews with owners/managers in small and medium-sized hotels. The interview data were analysed with the use of a purpose-built database and Structured Query Language for data manipulation. This study has identified four broad types of paths to knowledge management in small and medium-sized hotels. A hotel's choice of a path to knowledge management is essentially dependent on two defining aspects, the sources of revenue generation and knowledge management activities. The path knowledge concept reflects the growth visions of small and medium-sized hotels, whe re knowledge management is practised unconsciously as part of the integrated business operation. The PathFinder model represents the intentions of small and medium-sized hotels with regard to certain paths to knowledge management as influenced by various internal and external resources. The model provides strategic level decision making options for knowledge management and the basis for the development of future additions.

The Bok globule B335 is a small molecular cloud in the solar neighbourhood near the galactic plane. The aim for this three-paper-study is to construct and analyze the extinction for this globule. The method we apply is to use the light from field stars behind the cloud in broadband filters ranging from UV to the mid-infrared. We have observations performed at the ESO telescopes at La Silla and Paranal as well as at the Nordic 2.5 m telescope at La Palma. Together with images and spectra from 2MASS-, ISO- and Spitzer-archives we are able to cover the wavelength range from 0.35 to 24 μm. An important tool to analyze these observations results in order to get the extinction is the grid of synthetic stellar atmospheric spectra provided by Hauschildt (2005). The extinction so received is a result in itself. From the analysis of the extinction wavelength dependence we derive properties of the dust, especially its composition and grain size distribution. By modeling the grain size distribution we are able to find the extinction from the reddening of the stars. We find that the extinction in the optical wavelength 0.35 to 2 μm range nicely follows the functional form described by Cardelli et al. (1989). Our result from the wavelength range redward of 2 μm show an extinction dependent on the part of the cloud examined. For the rim of the cloud we get an extinction similar to that reported earlier for the diffuse interstellar medium. From the central parts of the cloud, however, a higher extinction was found. Our grain size model contains a carbonaceous particle distribution and a silicate one. The result can be explained by depletion of carbon onto carbonaceous grains and also by carbon onto all grains including the silicates. Our modeling of the extinction and our classification of the background stars allow us to - determine the distance to the globule - estimate the gas column density ratio - estimate the mass of globule - get a handle on the dust conversion processes through the grain size distribution   From the water- and CO-ice spectra we are able to estimate the ice column densities. We find similar ice column densities for the two ices. The estimates differ, when calculated from band strengths or from Lorenz-Mie calculations of ice mantles on the grain size distribution, by a factor of two.

Under the impact of double cards in the past two years, domestic banks have tightened the business of the double cards and been stricter on the examination of credit terms such as house loans with guarantees. The focus of credit business has been switched to corporate finance from consumer finance. The credit to small/medium enterprises is the main goal. In the long past, economic policies of the government have aimed at helping small/medium enterprises in sustainable development. From the data of White Paper on Small/medium Enterprises, close to 97.8 (over 1.16 million) companies in 2005 in Taiwan were small/medium enterprises, which have been the cornerstone of macroeconomic development in Taiwan. It is an urgent job to foster professional credit personnel to meet the needs of government¡¦s policies or in the overall financial environment. The purpose of this study is establish and develop the required knowledge, skills and qualities at work of credit personnel at banks to small/medium enterprises in order to help banks¡¦ recruitment, screening/training development, and improving/ehnahcing job performance to have the personnel make contribution to the banks. The process is literature exploration, job analysis and behaviorial interviews to establish competency structure and competency scale. Formal interviews are made with middle/high ranking supervisors at banks of different nature with over 10 years of experiences in lending to small/medium enterprises. Questionnaires are collected for statistics and analysis to develop the competency model of credit personnel. The conclusions are: 1. The required competency of credit personnel to small/medium enterprises includes product knowledge, market information,judgment,communication, activeness/aggresiveness, mofive of acheivment and establiment of relations. Banks of different nature have slightly views on the competency, which is resulted from the corporte culture, organization structure or other factors. Future researchers can focus on this. 2.For a successful credit staffer to small/medium enterprises, the most important is qualities in the competency, followed by professional knowledge. Skills are relatively less important. Judement is the most significant in the skill aspect, which is apparently different from that of common sales representatives. Future resarchers can focus on whether it has anything to do with the nature of the products sold. Keywords : competency, credit, credit personnel, small/medium enterprises