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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.
121

A Regime Shift Analysis of Poverty Traps in sub-Saharan Africa : Identifying key feedbacks and leverage points for change

Johnny, Musumbu Tshimpanga January 2012 (has links)
Smallholder livestock keeping and agriculture systems in the sub-Saharan Africa (SSA) seem to be caught into poverty traps, in as much as they cannot any longer provide ecosystem services on which local communities depend for their survival. I used a regime shifts framework to carry out a thorough assessment of these two case studies in arid and semi-arid lands and smallholder by identifying relevant traps and alternate desirable regimes. Using systems analysis and modelling, I drew casual loop diagrams of the two case studies, which helped me to identify the feedback loops that maintain the systems in undesirable traps and the external driving forces of change. A set of interventions points or leverage points were identified to change the dynamics of the systems and shift them towards more desirable regimes. Essentially, a structural change of both systems is called for if sustainable livelihoods in the rural areas of the SSA are to be seriously envisaged. Human capital investments present the main opportunity for facilitating escape from poverty by transforming farmers to non-farmers and livestock keepers to non-livestock keepers.
122

TEMPORARY THRESHOLD SHIFTS IN FINGERTIP VIBRATORY SENSATION FROM HAND-TRANSMITTED VIBRATION AND REPETITIVE SHOCK

MAEDA, SETSUO 05 1900 (has links)
No description available.
123

Der Zusammenhang von objektivem und subjektivem Blickort als Indikator für die visuelle Aufmerksamkeitsausrichtung

Helmert, Jens R. 02 September 2009 (has links) (PDF)
Normalerweise stimmen die Ausrichtung der Augen und die der visuellen Aufmerksamkeit überein. Frühere Arbeiten, vor allem im Kontext so genannter ‚Fixieren-Springen’ Paradigmen, haben gezeigt, dass zum Zeitpunkt der Programmierung einer neuen Sakkade die Aufmerksamkeit bereits zum Sakkadenziel verlagert wird. Bei Untersuchungen in natürlicheren Umgebungen konnte dieser Befund allerdings nicht gezeigt werden. Aus diesen teilweise widersprüchlichen Befunden ergibt sich die Fragestellung der vorliegenden Arbeit: Wie wirken sich visuelle Aufgaben am aktuellen Fixationsort innerhalb einer Sequenz von Blickbewegungen auf die Verlagerung der visuellen Aufmerksamkeit aus? Welche Rolle spielt dabei der Zeitpunkt innerhalb der aktuellen Fixation? Diese Fragen werden auf der Basis des Zusammenhangs zwischen objektivem und subjektivem Blickort untersucht. Als objektiver Blickort wird dabei der durch ein Blickbewegungsmesssystem ermittelte aktuelle Fixationsort begriffen. Während der Ausführung verschiedener visueller Aufgaben – Lokalisation, Identifikation und Katego¬risierung – wird der subjektive Blickort als derjenige bezeichnet und untersucht, den Probanden bei einer plötzlichen Unterbrechung ihrer aktuellen Tätigkeit angeben können. In einer Serie von drei Experimenten wurde getestet, welcher Zusammen¬hang zwischen objektivem und subjektivem Maß vor dem Hinter¬grund der verschiedenen Aufgaben und dem Zeitpunkt innerhalb der aktuellen Fixation besteht. Dabei wurden den Probanden in jedem Durchgang sechs kreisförmig angeordnete Piktogramme präsentiert, die im Uhrzeigersinn nacheinander zu betrachten waren. Zu einem nicht vorhersehbaren Zeitpunkt wurde die Betrachtung unterbrochen, wobei der subjektive Blickort durch einen Mausklick auf das aktuell betrachtete Piktogramm angegeben werden sollte. In einem vierten Experiment wurde eine blickgesteuerte Schreibumgebung untersucht, bei der auf der Basis der Ergebnisse der Experimente 1 bis 3 die Rückmeldung der eigenen Blickposition und die Schwellzeit zum Auslösen einer Taste systematisch variiert wurden. Es wurde davon ausgegangen, dass die Rückmeldung weniger an den aktuellen tatsächlichen, als an den subjektiven Blickort gebunden sein sollte. Schreiben mit den Augen setzt voraus, dass Buchstaben auf der Tastatur lokalisiert, und danach identifiziert werden müssen, um eine Entscheidung treffen zu können, ob die Taste ausgelöst werden soll oder nicht. Die vorhergehenden Experimente zum subjektiven und objektiven Blickort bei der Identifikation haben gezeigt, dass der subjektive hinter dem objektiven Blickort eher zurückbleibt. Aus diesem Grund ist anzunehmen, dass eine Verzögerung der Rückmeldung gegenüber der objektiven Blickposition als angenehm empfunden werden müsste. Es zeigte sich, dass die besten Ergebnisse in Bezug auf Fehlerrate und Schreibgeschwindigkeit bei Schwellzeiten um die 500 ms erreicht werden. Die subjektiven Einschätzungen der Probanden ergab eine signifikante Präferenz der verzögerten Rückmeldung. Insgesamt zeigen die Ergebnisse der Untersuchungen, dass der Zusammenhang zwischen subjektiven und objektiven Blickort nicht nur durch den Zeitpunkt innerhalb der aktuellen Fixation, sondern vor allem auch durch die momentan bearbeitete Aufgabe moduliert wird. Besonders letzteres wird in aktuellen Theorien der visuellen Aufmerksamkeit nur wenig beachtet. Für die vorliegenden Ergebnisse wird ein Erklärungsansatz entwickelt, der die Idee aufeinander aufbauender Ebenen der Informationsverarbeitung kognitiver Aufmerksamkeitsmodelle aufgreift. Besonders das von Velichkovsky (2002) vorgeschlagene Modell erweist sich dabei als fruchtbar, da es feiner differenziert, und darüber hinaus zwischen Hintergrundkoordination und Führungsebene unterscheidet. In diesem Sinne lassen sich die untersuchten Aufgaben mit einer zunehmenden Tiefe der Verarbeitung assoziieren. Damit einhergehend steigt die Komplexität der zu verarbeitenden Information und sinkt die Wahr¬scheinlichkeit, dass Informationen jenseits der aktuellen Fixation abgerufen werden können: Im Gegenteil, früh innerhalb einer Fixation werden bei tiefer Verarbeitung sogar noch Informationen aus der vorhergehenden Fixation berichtet. Diese Konzeptionalisierung der Ergebnisse gestattet es, vordergründig unterschiedliche Befunde aus ‚Fixieren und Springen’ Paradigmen und Studien in natürlicheren Umgebungen zu integrieren. Die Ergebnisse von Experiment 4 zeigen, dass dieser Erklärungsansatz auch praktische Ableitungen für die Gestaltung von blick¬gesteuerter Interaktion mit dem Computer geeignet ist. Die führende Aufgabe bei solchen intentionalen Fixationen bestimmt die Art und Weise, wie der subjektive Blickort dem Nutzer zurückgemeldet werden sollte.
124

The influence of work patterns on lifestyle behaviours and cardiovascular risk in female hospital workers

Kirk, MEGAN 26 September 2009 (has links)
BACKGROUND: The prevalence and burden of cardiovascular disease (CVD) is a concern. While CVD events will occur later in a woman’s life, modifiable risk factors for CVD occur earlier during adult years. While, there is strong evidence linking modifiable risk factors to CVD, the influence of the work environment on CVD risk is poorly understood. OBJECTIVES: The study objectives were to: 1) determine the prevalence of cardiovascular risk indicators; 2) determine the relationships between work patterns and lifestyle behaviours in female hospital workers; 3) determine the relationships between work patterns and cardiovascular risk indicators; and 4) determine the relationships between work patterns, lifestyle behaviours and cardiovascular risk while controlling for covariates. METHODS: Participants were female hospital workers (N= 466) from 2 hospital sites in Southeastern Ontario. Cardiovascular risk data were obtained through anthropometric measurements, blood sampling and self-report. Work pattern data were collected through self-report and linked with hospital administrative work data. Lifestyle behaviour data were obtained through self-report using validated questionnaires. Metabolic syndrome was classified in accordance with the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP) (III) guidelines. RESULTS: Approximately 1 in 4 female participants had the metabolic syndrome, with elevated waist circumference being the most common CVD risk factor. After adjustments, the multivariate analysis found a few key significant associations between irregular work patterns, specifically extended shifts and CVD risk, specifically elevated systolic and diastolic blood pressure. However, consistent with the literature, the bivariate analyses revealed that after 6 or more years of shift work, female workers were more likely to develop the metabolic syndrome (OR 1.9, 95% CI 1.12, 3.17) and abdominally obesity (OR = 2.0, 95% CI, 1.31, 3.11). CONCLUSIONS: The findings from this study suggest that generally work patterns do not influence the development of unhealthy behaviours and cardiovascular risk factors, although a few key exceptions exist. Further research is needed to elucidate the mechanisms linking harmful and protective work pattern characteristics to CVD risk. Given the prevalence of abdominal obesity and overall CVD risk, hospital decision makers need to consider cardiovascular health within healthy workplace initiatives as the healthcare workforce is aging. / Thesis (Master, Nursing) -- Queen's University, 2009-09-24 18:39:03.718
125

Design of a field-intensified interior permanent magnet synchronous machine for electric vehicle application

Prins, Michiel Hendrik Albertus 04 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The focus of this thesis is on the optimal design and evaluation of FI-PM machines to be used with a MG transmission drive-train for EV application. The machines presented are optimised using a gradient-based optimisation algorithm of the VisualDoc software together with FE software and Python scripts. Each machine is optimised for its own objective function. The focus is to reduce expensive rare earth material. High torque ripple issues of the optimised machines are solved by implementing a relatively new topology where the rotor poles/barriers are made asymmetric. The asymmetric rotor topology implemented is effective and can be used as an alternative for rotor stack skewing. PM demagnetisation and rotor deformation studies are conducted on the optimum designed machines to ensure that no PM demagnetisation on the surface of the PMs and critical rotor deformation occur. The FE performance results of the optimum designed machines are shown and discussed. One of the optimum designed FI-PM machines is manufactured and tested in the laboratory. The FE and measured results of the machine are compared and shows good correlation. The saliency performance of the optimum designed machines are evaluated as it determines its position sensorless control capability. It is shown that the saliency ratios increase linearly with load, making it favourable for position sensorless control. It is also shown that the asymmetric rotor topologies introduced a larger mutual inductance compared to their symmetric counterparts, thus higher cross-coupling is present in these rotors and therefore a higher saliency shift, which is undesirable. Two case studies are performed in order to improve saliency performance. The objective of the first case study is to improve the saliency shift by reducing the flux leakage paths in the rotor. The objective of the second case study is to optimise a FI-PM machine in order to improve the saliency ratio and -shift. The results of the two case studies are compared with the saliency performance of the other machines. / AFRIKAANSE OPSOMMING: Die fokus van hierdie tesis is op die optimale ontwerp en evaluering van veld versterking permanente magneet masjiene vir veelvoudige-rat elektriese voertuig toepassings. Die masjiene teenwoordig is geoptimeer met behulp van ’n helling-gebaseerde optimering algoritme. Elke masjien is geoptimeer vir sy eie doel funksie. Die fokus is om duur seldsame permanent magneet materiaal te verminder. Hoë wringkrag-rimpeleffek van die optimale masjiene word opgelos deur die implementering van ’n relatief nuwe topologie waar die rotor pole/vloedbarrière asimmetries gemaak word. Die asimmetriese rotor topologie wat geimplementeer is, is effektief en kan dus as ’n alternatief vir die rotor stapel skeef metode gebruik word. Permanent magneet demagnetisering en rotor vervorming studies is ook uitgevoer op die optimum ontwerpte masjiene om te verseker dat geen demagnetisering plaasvind nie en ook geen kritiese rotor vervorming nie. Die eindige-element resultate van die optimum ontwerpte masjiene word getoon en bespreek. Een van die optimum ontwerpte veld versterking permanente magneet masjiene is vervaardig en getoets in die laboratorium . Die eindige-element en gemete resultate van die masjien word vergelyk en toon goeie korrelasie. Die speek prestasie van die optimum ontwerpte masjiene word geëvalueer aangesien dit die sensorlose posisie beheer vermoë bepaal. Daar word getoon dat die speek koëffisiënt verhoog lineêr met vrag wat dit gunstig maak vir posisie sensorlose beheer . Daar word ook gewys dat die asimmetriese rotor topologie ’n groter wedersydse induktansie het in vergelyking met hul simmetriese eweknieë, dus is daar hoër kruis-koppeling teenwoordig in die rotors en dus ’n ho¨er speek skuif, wat ongewens is. Twee gevallestudies om speek prestasie te verbeter is uitgevoer. Die doel van die eerste gevallestudie is om die speek skuif te verbeter deur die vermindering van die vloed lekkasie paaie in die rotor. Die doel van die tweede gevallestudie is om ’n veld versterking permanente magneet masjiene te optimeer ten einde die speek koëffisiënt en - skuif te verbeter. Die resultate van die twee gevallestudies word vergelyk met die speek prestasie van die ander masjiene.
126

Detecting Political Framing Shifts and the Adversarial Phrases within\\ Rival Factions and Ranking Temporal Snapshot Contents in Social Media

January 2018 (has links)
abstract: Social Computing is an area of computer science concerned with dynamics of communities and cultures, created through computer-mediated social interaction. Various social media platforms, such as social network services and microblogging, enable users to come together and create social movements expressing their opinions on diverse sets of issues, events, complaints, grievances, and goals. Methods for monitoring and summarizing these types of sociopolitical trends, its leaders and followers, messages, and dynamics are needed. In this dissertation, a framework comprising of community and content-based computational methods is presented to provide insights for multilingual and noisy political social media content. First, a model is developed to predict the emergence of viral hashtag breakouts, using network features. Next, another model is developed to detect and compare individual and organizational accounts, by using a set of domain and language-independent features. The third model exposes contentious issues, driving reactionary dynamics between opposing camps. The fourth model develops community detection and visualization methods to reveal underlying dynamics and key messages that drive dynamics. The final model presents a use case methodology for detecting and monitoring foreign influence, wherein a state actor and news media under its control attempt to shift public opinion by framing information to support multiple adversarial narratives that facilitate their goals. In each case, a discussion of novel aspects and contributions of the models is presented, as well as quantitative and qualitative evaluations. An analysis of multiple conflict situations will be conducted, covering areas in the UK, Bangladesh, Libya and the Ukraine where adversarial framing lead to polarization, declines in social cohesion, social unrest, and even civil wars (e.g., Libya and the Ukraine). / Dissertation/Thesis / Doctoral Dissertation Computer Science 2018
127

Geodetická sledování prostorových polohových změn rekultivovaných svahů pohornické krajiny. / Observation of the slope slides at localities of reclamation at the sites of open-cast mines by geodetic methods.

DVOŘÁKOVÁ, Eliška January 2009 (has links)
The project is about the evaluation of 2 stage measurements in local coordinate net Rabenov which were done in 2007. This local coordinate net was set for monitoring of slope shifts at the former mining area near Ústí nad Labem. In concrete terms in south - eastern part of Chabařovice mine. For terrestrial measurements were used total stations Leica TC 1700 and 1800 and GPS measurement on the basis of GPS surveying system Trimble 5700. The achieved values - horizontal angles, oblique distance, and zenithal angles were reduced onto joins of stabilization marks. From these reduced values the coordinates of standpoints were computed by evaluation of three-dimensional net. These determined coordinates were compared with the zero stage of measurement and deviations were computed. Each computation was done by geodetic computer software Rocinante. Next task was the testing of the different types of reflecting targets.
128

Is gear-based management of herbivorous fish a viable tool to prevent or reverse phase shifts in coral reefs? : Linking resilience theory to practice

Dilasser, Quentin January 2011 (has links)
Herbivorous reef fish are a key functional group for the ecological resilience of coral reefs. Asthey feed on algae, a major resource competitor of coral polyps, they can prevent and reversecoral-macroalgal phase shifts. The resilience of the reefs against such phase shifts is given bythe ability of herbivores to keep the system in a cropped state from filamentous algae or bytheir capacity to feed on macroalgae. Most of the management plans that aim to protect coralreefs have been focusing on the establishment of marine protected areas or no-take areas wherefishing activities are strictly restricted or prohibited. In low-income countries, such managedareas can be difficult to accept from a fisher´s perspective and lack of money also tends to leadto limited surveillance capabilities and lowered compliance. These challenges are important toaddress when managing small-scale fisheries and where fish are considered as both, amarketable commodity and a subsistence good.A perhaps less contentious strategy for fishers is gear-based management, where the use offishing gears that are detrimental to coral reef resilience are restricted and at the same timegears that do not compromise resilience are promoted. This study aims to investigate how ninedifferent fishing gears (i.e. different lines, traps, nets and spears) used in the coral reef fisheriesof Zanzibar (Tanzania) capture herbivorous reef fish that can prevent (preventers) or reverse(reversers) coral-macroalgal phase shifts. Two interesting findings emerged from the study.First, different fishing gears had different impacts on these two functional groups where lines,large traps and seine nets fisheries had most impacts. Second, there were monsoonaldifferences in the catch of preventers and reversers. These findings are discussed in relation toi) similar studies conducted in different reef environments and ii) the feasibility of gear-basedmanagement in Zanzibar.
129

Román De usynlige Roye Jacobsena v německém a českém překladu / German and Czech Translations of Roy Jacobsen's Novel De usynlige

Krchová, Andrea January 2017 (has links)
The aim of this master's thesis is to create an analysis of the Czech and German translations of Roy Jacobsen's novel De usynlige, which was published by Cappelen Damm in 2013. The first part includes a biography of Roy Jacobsen and a literary analysis of his novel. Translators Jarka Vrbová. Gabriele Haefs and Andreas Brunstermann are introduced as well as interviewed. The mainstay of this thesis is to analyse the Czech and German translations. The analysis is focused on the lexical, syntactic and stylistic level and based on Jiří Levý's theory of a faithful and free translation. Afterwards, the translation methods in both translations are deduced and compared with each other. The thesis presents several topics in the field of publishing practices.
130

Extending the boundaries of the usage of NMR chemical shifts in deciphering biomolecular structure and dynamics

Sahakyan, Aleksandr B. January 2012 (has links)
NMR chemical shifts have an extremely high information content on the behaviour of macromolecules, owing to their non-trivial dependence on myriads of structural and environmental factors. Although such complex dependence creates an initial barrier for their use for the characterisation of the structures of protein and nucleic acids, recent developments in prediction methodologies and their successful implementation in resolving the structures of these molecules have clearly demonstrated that such barrier can be crossed. Furthermore, the significance of chemical shifts as useful observables in their own right has been substantially increased since the development of the NMR techniques to study low populated 'excited' states of biomolecules. This work is aimed at increasing our understanding of the multiple factors that affect chemical shifts in proteins and nucleic acids, and at developing high-quality chemical shift predictors for atom types that so far have largely escaped the attention in chemical shift restrained molecular dynamics simulations. A general approach is developed to optimise the models for structure-based chemical shift prediction, which is then used to construct CH3Shift and ArShift chemical shift predictors for the nuclei of protein side-chain methyl and aromatic moieties. These results have the potential of making a significant impact in structural biology, in particular when taking into account the advent of recent techniques for specific isotope labelling of protein side-chain atoms, which make large biomolecules accessible to NMR techniques. Through their incorporation as restraints in molecular dynamics simulations, the chemical shifts predicted by the approach described in this work create the opportunity of studying the structure and dynamics of proteins in a wide range of native and non-native states in order to characterise the mechanisms underlying the function and dysfunction of these molecules.

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