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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

Framtidens ledare hos tjänsteföretag : En fall studie på UAE-logistics

Novella, Carola, Dimitriadis, Johanna January 2006 (has links)
I en alltmer turbulent och ombytlig värld går det inte att leda dagens kundstyrda produktion med traditionellt ledarskap. Dagens ledare påverkas av olika faktorer som måste beaktas för att kunna styra ett framgångsrikt företag. Uppsatsens syfte är att utvärdera och analysera UAE-logistics ledarskap genom att undersöka deras internkommunikation utifrån en teoretisk grund. Metoden som används i undersökningen är en gap-analys som används för att se om det råder samstämmighet mellan gruppledarna och de anställda. I slutsatsen besvaras problemfrågan: Vilka faktorer måste den moderna ledaren på tjänsteföretag beakta i sitt ledarskap för att förbli konkurrenskraftig? En faktor som måste beaktas är att den interna kommunikationen måste fungera bra för att motivera, engagera och involvera anställda. En annan viktig faktor är att strategierna som är valda utifrån företagets situation måste vara förenliga med företagets idésystem, som är verkligheten där de anställda arbetar. Råder samstämmighet mellan dessa delar kan slutsatsen dras att den rådande organisationsformen är passande för att kunna omvandla företagets strategier, som är valda utifrån externa faktorer, till den tjänst som efterfrågas. En tredje faktor är att ledaren måste delegera ut mer ansvar till de anställda, eftersom de arbetar närmast kunden och behöver skräddarsy tjänsten för att skapa ett mervärde för kunden. Med det ökade inflytandet måste även ökad kunskap erbjudas, för att den anställde ska kunna ta kvalificerade beslut efter den aktuella situationen. En fjärde faktor, som den moderne ledaren måste ta hänsyn till, är vikten av att ha en god intern marknadsföring, som avser att effektivt träna, motivera, engagera och involvera sina anställda för att kunna uppnå större kundtillfredsställelse. Faktor nummer fem är vikten av att implementera kontinuerlig lärande för att företaget ständigt ska kunna anpassas till förändringar i omvärlden. Genom att ha ett kontinuerligt informationsflöde uppåt, från de anställda till ledningen, informerar den anställde som arbetar närmast kunden om nya trender, nya behov som kunder efterfrågar och ledningen kan använda informationen för att skapa nya tjänster som täcker kundens nya behov och företaget förblir konkurrenskraftigt. Den sjätte faktorn är vikten av att företagen använder sig utav styrformen processtyrning som betraktar arbetet som en öppen process som är mottaglig för kontinuerliga förändringar, som företagen måste anpassa sig till eftersom de externa faktorerna konstant förändras.
132

Transient Mixed Synapses Regulate Emerging Connectivity in Simple Neuronal Networks

Richardson, Jarret Keith 16 December 2013 (has links)
The electrical synapse was first described over 50 years ago. Since that time appreciation of its complexity and importance has grown, including the hypothesis that early transient formation of these synapses is important to adult patterns of connectivity in neural networks. Presented in this dissertation are studies utilizing identified neurons in cell culture from the snail Helisoma trivolvis to examine discrete periods of electrical synapse formation during regeneration with sustained or transient expression. Extensive knowledge of connectivity patterns of the buccal neurons of Helisoma in cell culture and the ganglia, provide a useful framework for looking at modulation and manipulation of electrical synapses and their impact and emerging connectivity in a simple neuronal network. Two types of electrical connections were observed those that were transient, between a B19 and a B110 and those that were sustained, between a B19 and another B19. Dopamine (DA) modulation of forming electrical synapses (FES) produces a synapse specific effect at those either destined to be transient (TES) or sustained (SES) and may be a direct effect on the gap junctions at the synapses, as is the case at TES, or an indirect effect on other membrane currents, as seen in SES. DA modulation produces different outcomes at SES-centered networks and TES-centered networks with respect to new chemical synapse formation, demonstrating network-dependent effects of electrical synapse modulation. Pharmacological blockade of chemical and electrical components at forming mixed synapses in some cases alters subsequent synapse formation although due to the variable nature does not appear to be a direct interaction between chemical and electrical synapses. Three-cell networks appear to display a balancing mechanism for overall electrical coupling when electrical synapses are blocked suggesting a competition for some resource in the construction or trafficking of gap junctions. In addition to electrophysiological examinations, network coupling can be assessed utilizing fluorescent calcium imaging to look at coincidence of calcium changes as an output for coupling between cells. This technique provides a useful tool for less invasive studies of neuronal networks and the impact of coupling at mixed synapses.
133

Muscles that see: early muscle activations are time-locked to the onset of visual targets

King, Geoffrey Llewellyn 03 October 2007 (has links)
The visual grasp reflex provides automatic orienting of gaze (the visual axis in space) to novel visual stimuli. Previous studies have demonstrated activation of neck muscles of awake monkeys appearing at a short fixed latency (55 to 95 ms) after visual target presentation, regardless of whether or when saccades are made. The purpose of these early visually-driven muscle activations may be to prime head rotation required as a part of the coordinated eye-head movement to the target. Similar orienting responses might be found for visually guided reaching. Here, we explore early visually-driven muscle activations of the human upper limb immediately preceding planar reaching movements. Subjects performed reaches towards small visual peripheral targets while upper limb kinematics were recorded and intramuscular electromyography was collected from four shoulder and elbow muscles. Subjects maintained their right hand at a central fixation marker that was extinguished for a gap period (200 ms) prior to appearance of a peripheral target. Subjects were instructed to reach to the target as quickly as possible. Some subjects exhibited a short burst of muscle activity (about 20 ms duration) time-locked to visual target onset. This burst occurred around 85 ms to 105 ms after target onset and preceded the onset of muscle activity associated with volitional arm motion by about 100 ms. Notably, this burst was dependent on target location: visually-driven muscle activity occurred in right shoulder extensor muscles for rightward targets and was absent for leftward targets. In order to better dissociate the visual burst from volitional motor activity, we employed a delay paradigm. No time-locked muscle activity was present in the delay task either after the target appeared or after the fixation marker was extinguished. This suggests that the visual burst is dependent on the imminence of voluntary movement and the laterality of the target. We conclude that the appearance of a visual target can result in short-latency activity on the arm musculature that is appropriate for orienting the arm to the target. / Thesis (Master, Neuroscience Studies) -- Queen's University, 2007-09-27 09:42:55.337
134

Achievement gap in the highly selective German school system : a critical analysis of strategies for equitable education in a primary school

Mueller, Tessa 08 July 2008 (has links)
Germany has historically been a country where peoples from various countries have worked and settled, and diverse cultures have existed. Yet, German schools still adhere to what could be described as assimilative and deficit-oriented practices (Gogolin & Krüger-Potratz, 2006; Schanz, 2006). In addition, the German education system has a high degree of social selection (Auernheimer, 2006a) that creates severe educational inequities between German and immigrant students. After four years of primary school, students are streamed into one of the three major secondary school types Gymnasium, Realschule, and Hauptschule, based on achievement. Since these schools provide education of varying quality, students are denied equal opportunities. The purpose of this study is to explore and critically analyze possible ways to alleviate the existing inequities in the German school system, which are reflected in the achievement gap between immigrant and German mainstream students (Hormel & Scherr, 2004; Schofield, 2006). Using a case study approach, I analyze the educational work of the award-winning German primary school “Kleine Kielstraße” located in Dortmund with a culturally and linguistically diverse student population, situated in a socially disadvantaged district. My purpose was to gain insight into the school’s practices and strategies for recognizing diverse students and for striving to provide equitable education for all students. Despite the strategic steps taken by this school based on the competence and the enthusiasm of the principal and staff, it is quite evident that structural changes in the highly selective, three-tiered German secondary school system are required before educators can effectively challenge the built-in inequities. Though the German school system is designed and programmed to discriminate and deny equal opportunity, the participating school demonstrates a pedagogical approach that provides more equitable education for all students regardless of their cultural background and ethnicity. This thesis explores these strategies of the school to create an understanding that a progressive “Intercultural Pedagogy” can go a long way in providing a better education despite structural inequities. / Thesis (Master, Education) -- Queen's University, 2008-07-03 15:00:06.839
135

Electrical transport properties of n-Type InP

Beaudoin, Mario January 1988 (has links)
InP obtained by metal-organic vapor phase epitaxy, with properties similar to GaAs, shows mobilities approaching the theoretical maxima at low temperatures. However, the corresponding values remain abnormally low at room temperature where a pronounced electronic excitation to the conduction band is observed simultaneously. This reduction of the mobility is attributed to the presence of deep centers that are electrically inactive at low temperatures but become excited when the temperature increases. A model based on an iterative solution to the Boltzmann equation and accounting for the usual scattering mechanisms, including inelastic interactions, is able to explain the data perfectly and shows that a very high mobility at low temperature is not a sufficient measure of the purity for this material. The binding energy of the deep centers depends on the organo-metalic source used for the growth. This links the solution of this problem to the purification of the chemicals. Depletion effects at the interfaces did not appear to be significant. (Abstract shortened by UMI.)
136

THE GAP BETWEEN WHAT TAXPAYERS WANT AND WHAT TAX PROFESSIONALS THINK THEY WANT: A REEXAMINATION OF CLIENT EXPECTATIONS AND TAX PROFESSIONAL AGGRESSIVENESS

Stephenson, Teresa 01 January 2006 (has links)
The purpose of this dissertation is to resolve an apparent conflict between the services that tax preparers provide and the tax preparation services taxpayers seek. Some literature demonstrates that tax professionals equate client advocacy with taking aggressive tax positions and minimizing taxes. Other literature suggests taxpayers seek to increase accuracy and reduce the probability of tax audit when they hire a tax professional. This difference is an "expectation gap."The methodology employed to examine this issue is a survey of tax professionals at various levels of expertise. This survey asks tax preparers what they believe motivates their clients to seek professional tax preparation services. It also asks how aggressive a tax professional should be in minimizing clients' taxes. A similar survey sent to taxpayers who use the services of a tax preparer asked the same questions about taxpayers' primary motivation in seeking professional tax preparation services and then about how they believe their tax preparer would answer the questions about aggressive tax reporting.This dissertation extends the research in several ways. In previous studies, taxpayer motivation has been determined by using a simple checklist or an open-ended question. Instead of using these approaches, I developed a scale using methods that rigorously test for validity. In measuring client advocacy, I use a scale that has been recently developed and used in the literature. While previous research has shown the disparity between what tax professionals provide and what taxpayers want, no study has asked each group how they believe the other group will respond. This will provide a measure of the degree of understanding each group has of the other.This research show that there is an expectation gap between taxpayers and their tax preparers at all levels, and that this gap is statistically significant. However, the actual size of the gap is small; accuracy and client advocacy have the largest gaps. Additional findings are that timesavings is more important to taxpayers with children, that contact with the IRS is correlated with a lower desire to avoid it, and that lower tax knowledge is correlated with stronger desire for an accurate return.
137

Mind the gap : En studie om samarbetet mellan entreprenörer och affärsänglar

Wallén, Marcus, Josefsson, Adam January 2014 (has links)
Today there are a number of different financing options but few of them are suitable for start-up companies. Business angels are in that case an exception and a suitable investor in these companies. Business angels are individuals who invest in young companies and differ from other financiers in the sense that the collaboration with the company is closer. Business angels are although few in numbers while the young companies often tend to be in most need of funding and has the greatest potential to grow. The purpose of this study is to gain a deeper understanding of the cooperation between entrepreneurs and business angels and to identify which effects the financial gap have on these financial associations. Business angels and entrepreneurs collaboration are hard to interpret and therefore demanded a deeper examination. We thus used a qualitative method consisting of six different interviews in three different cases. The study shows that established collaborations between entrepreneurs and business angel’s seem to be affected by the financial gap to a great extent, which has been expressed in negative consequences. The financial gaps effects on the cooperation mainly takes form in the initial assessment process where the contractors expressed difficulties in the search of funders due too the limited number of stakeholders. We have identified communication problems and grievances between the entrepreneurs and business angels in the form of wills and we see these problems as a result of the initial problem.
138

Spontaneous polarization effects in nanoscale systems based on narrow-gap semiconductors

Isaev, Leonid January 2005 (has links)
In the framework of the two-band (Dirac) model, we analyze the electronic structure of nanoscale systems, based on narrow-gap semiconductors of Pb,_xSnx (Se, S) type. Themain attention is paid to the influence of properties of the surface, encoded in appropriate boundary conditions, on the size-quantized spectrum. From this point of view we consider two types of systems: spherical (quantum dots) and quasi one-dimensional (films).It is shown that the spectrum of the spherical quantum dot consists not only of usual size-quantized states, located above the gap edge, but also surface modes residing inside the gap. Such states manifest themselves in the far infrared part of the absorption spectrum, the measurement of which allows one to extract information about the dot surface.Next, we consider a film with the energy gap modulated in the <111> (growth) direction. It is shown that the spectrum of the infinite crystal possesses a supersymmetrical structure. The film boundaries, generally speaking, destroy the supersymmetry, i.e. size-quantized subbands turn out to be spin-split. However, there exists a class of boundary conditions that do not lift spin degeneracy. Physically, in this case there is no band mismatch at interfaces. Our central statement, therefore, consists of the following: even when the inversion symmetry is destroyed by the bulk inhomogeneity, the spin-splitting of the spectrum is a purely surface effect. This is illustrated on a simple example, when the energy gap varies linearly over the film width.Finally, we investigate the role of boundary conditions in the problem of scattering of spinor waves by a quantum dot. It is shown that the existence of surface states greatly modifies the scattering data; in particular, outgoing waves may turn out to be fully polarized. / Department of Physics and Astronomy
139

The Role of Gap Junctions in Brain Glucose Deprivation and Glucose Reperfusion

Sugumar, Sonia 07 July 2014 (has links)
Hypoglycemia is a severe side effect of insulin overdose in the diabetic population and can result in various neurological sequalae including seizures, coma, and brain death. There is still a limited understanding of the generation and propagation of hypoglycemic seizures, which may exacerbate hypoglycemia-induced neuronal damage. Moreover, glucose reperfusion after a period of transient hypoglycemia has been shown to cause neuronal hyperexcitability which can have further damaging effects. Gap junctional communication can be involved in the spread of hypoglycemic injury in two ways: 1) by providing a cytoplasmic continuity in which seizures can easily propagate and 2) by engaging the astrocytic network in metabolic compensation as well as enhancing astrocytic buffering of K+. This study aims to investigate the role that gap junctions play during brain energy deprivation. Results from these experiments show that gap junction blockade can have a neuroprotective role during hypoglycemia and glucose reperfusion.
140

Simulation of an Electrical Machine : with superconducting magnetic bearings

Bahceci, Mesut January 2015 (has links)
This master thesis investigates if there is an induction motor configuration that can be used with a flywheel energy storage system, that uses passve superconducting magnetic bearings (SMBs). The configurations should be able to be designed with induction motor building blocks that are commercially available. The method used to investigate this was simulations of different induction motor configurations in the finite element analysis software COMSOL. The simulations show that when larger air-gaps than that of a commercial IM unit are used it is possible to use SMBs in the IM. SMBs have the advantage of having zero resistance which makes it possible to store energy without resistance losses. However it was found that by using and IM with SMBs the generated power would be lower than that of a commercial unit.

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