61 |
Improved shortest path algorithms by dynamic graph decomposition : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Computer Science and Software Engineering in the University of Canterbury /Tian, Lin. January 2006 (has links)
Thesis (M. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references (p. 77-79). Also available via the World Wide Web.
|
62 |
Path and cycle decompositionsDinavahi, Chandra, Rodger, C. A. January 2008 (has links) (PDF)
Thesis (Ph. D.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references (p. 50-51).
|
63 |
On the shortest path and minimum spanning tree problemsPettie, Seth, January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.
|
64 |
Using the structure of d-connecting paths as a qualitative measure of the strength of dependence /Chaudhuri, Sanjay, January 2005 (has links)
Thesis (Ph. D.)--University of Washington, 2005. / Vita. Includes bibliographical references (p. 94-95).
|
65 |
Discovering Pathways to Sustainability: Small Communities in TransitionJanuary 2011 (has links)
abstract: Driven by concern over environmental, economic and social problems, small, place based communities are engaging in processes of transition to become more sustainable. These communities may be viewed as innovative front runners of a transition to a more sustainable society in general, each one, an experiment in social transformation. These experiments present learning opportunities to build robust theories of community transition and to create specific, actionable knowledge to improve, replicate, and accelerate transitions in real communities. Yet to date, there is very little empirical research into the community transition phenomenon. This thesis empirically develops an analytical framework and method for the purpose of researching community transition processes, the ultimate goal of which is to arrive at a practice of evidence based transitions. A multiple case study approach was used to investigate three community transitions while simultaneously developing the framework and method in an iterative fashion. The case studies selected were Ashton Hayes, a small English village, BedZED, an urban housing complex in London, and Forres, a small Scottish town. Each community was visited and data collected by interview and document analysis. The research design brings together elements of process tracing, transformative planning and governance, sustainability assessment, transition path analysis and transition management within a multiple case study envelope. While some preliminary insights are gained into community transitions based on the three cases the main contribution of this thesis is in the creation of the research framework and method. The general framework and method developed has potential for standardizing and synthesizing research of community transition processes leading to both theoretical and practical knowledge that allows sustainability transition to be approached with confidence and not just hope. / Dissertation/Thesis / M.S. Sustainability 2011
|
66 |
Geodesic paths and topological charges in quantum systemsGrangeiro Souza Barbosa Lima, Tiago Aecio 16 December 2016 (has links)
This dissertation focuses on one question: how should one drive an experimentally prepared state of a generic quantum system into a different target-state, simultaneously minimizing energy dissipation and maximizing the fidelity between the target and evolved-states? We develop optimal adiabatic driving protocols for general quantum systems, and show that these are geodesic paths.
Geometric ideas have always played a fundamental role in the understanding and unification of physical phenomena, and the recent discovery of topological insulators has drawn great interest to topology from the field of condensed matter physics. Here, we discuss the quantum geometric tensor, a mathematical object that encodes geometrical and topological properties of a quantum system. It is related to the fidelity susceptibility (an important quantity regarding quantum phase transitions) and to the Berry curvature, which enables topological characterization through Berry phases.
A refined understanding of the interplay between geometry and topology in quantum mechanics is of direct relevance to several emergent technologies, such as quantum computers, quantum cryptography, and quantum sensors. As a demonstration of how powerful geometric and topological ideas can become when combined, we present the results of an experiment that we recently proposed. This experimental work was done at the Google Quantum Lab, where researchers were able to visualize the topological nature of a two-qubit system in sharp detail, a startling contrast with earlier methods. To achieve this feat, the optimal protocols described in this dissertation were used, allowing for a great improvement on the experimental apparatus, without the need for technical engineering advances.
Expanding the existing literature on the quantum geometric tensor using notions from differential geometry and topology, we build on the subject nowadays known as quantum geometry. We discuss how slowly changing a parameter of a quantum system produces a measurable output of its response, merely due to its geometric nature. Next, we topologically characterize different classes of Hamiltonians using the Berry monopole charges, and establish their topological protection. Finally, we explore how such knowledge allows one to access topologically forbidden regions by adiabatically breaking and reestablishing symmetries.
|
67 |
IMPACTS OF CONCENTRATED FLOW PATHS ON CROP YIELDS AND WATER QUALITY IN SOUTHERN ILLINOIS ROW CROP AGRICULTUREEnger, Matthew 01 August 2018 (has links)
Sediment and nutrient loss from agricultural landscapes contributes to water quality impairment and has the potential to impact crop yield. Best management practices (BMPs) such as riparian buffers have been designed to combat these issues; however, concentrated flow paths (CFPs) reduce their effectiveness and are often overlooked in agricultural fields. Conventional management of CFPs is to fill and grade them, however this provides only a short term solution leading to their reformation and increased sediment loss. The objectives of this project were: i) to determine if the filling of CFPs influence crop growth (yield and biomass), ii) determine a distance at which crop growth is no longer influenced by CFPs, iii) assess the impact that topography and CFPs have on crop growth, iv) analyze water quality in surface runoff leaving crop fields via CFPs, and v) develop an economic analysis for CFP’s influence on crop returns. Six small agricultural catchments, CFPs, and topographic positions (i.e., depositional, backslope, and shoulder) were delineated using ArcGIS and LiDAR data. In each catchment, six 4 m2 plots were established along CFPs where crop biomass and crop yield were measured. Additionally, six plots with no influence from CFPs were established as reference plots. Surface water quality was assessed by taking edge-of-field grab samples at the CFP outlet during significant rain events (i.e., precipitation exceeding 2.5 cm). Water samples were analyzed for total suspended solids (TSS), total phosphorus (TP), dissolved reactive phosphorus (DRP), ammonium-nitrogen (NH4+-N), and nitrate-N (NO3- -N). Through this study it was shown that CFPs served as a conduit for transporting nutrient and sediment laden runoff to receiving waters, that increasing/decreasing distance from CFPs had an impact on crop yields, and that there was no crop yield advantage from the filling of CFPs vs. leaving them unfilled. Median values for NO3-N (1.85 mg L-1) and TSS (140 mg L-1) in the Fill catchments were higher than the No-Fill catchments (0.77 mg L-1 and 35.5 mg L-1, respectively), while DRP and TP concentrations were higher in the No-Fill catchments (1.31 mg L-1 and 2.37 mg L-1, respectively) compared to the Fill catchments (0.91 mg L-1 and 1.83 mg L-1, respectively) over the growing season. Crop biomass and yield results between the depositional and backslope positions were similar regardless of treatment, but were lower than the reference plots and shoulder position. Results from the economic analysis on the cost of farming in/near CFPs indicated that the economic return was greatly dependent on precipitation. CFPs are generally concave positions on the landscapes and have been eroded to a clayey subsoil, both resulting in greater water accumulation and retention than elsewhere in the field. During wetter years, an economic loss was incurred nearest to the CFP and during drier years, sites nearest to CFPs saw positive returns. Farmers and land managers may consider implementing stabilization measures, such as grassed waterways, in CFPs since crop yields are typically lower in wetter years, there’s increased cost to maintain these areas, and accelerated sediment loss can exacerbate the crop yield losses and impact on water quality.
|
68 |
Trabalhadores na "fronteira": experiências dos sacoleiros e laranjas em Foz do Iguaçu - Ciudad Del Este (1990/2006) / Workers in the border: experience of sacoleiros and laranjas in Foz do Iguacu - City del Este (1990/2006)Davi, Elen Patricia de Jesus Silva 13 March 2008 (has links)
Made available in DSpace on 2017-07-10T17:55:43Z (GMT). No. of bitstreams: 1
Elen Patricia de Jesus Silva Davi.pdf: 1235823 bytes, checksum: 1e2c723bc3be71b31bc09217270f9867 (MD5)
Previous issue date: 2008-03-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This dissertation aims to argue part of the experiences and the way of living of the people who contraband goods from Paraguay to Brazil, called sacoleiros and laranjas, as well as their work relation and their relation with Foz do Iguaçu, a town which was built from the established trade in the border of Brazil and Paraguay. Having this focus, I intended to understand and discuss these workers relations with the public and private organs (such as the IRS, the City hall, the Press), starting from their dynamics, their forged work strategies, as well as the established meanings in relation to this activity and the city. I also intended to understand how these people interact as a working class, from their paths, migrations, individual and collective experiences, as well as their own ways of living, inserting themselves, acting and interpreting the urban space. Finally, unmasking the dynamics of these workers also turned out to be a way of placing those workers' memoirs as a part of the construction of the social spaces, reaffirming their condition as production agents in the city of Foz do Iguaçu / Essa dissertação visa discutir parte das experiências e os modos de viver dos chamados sacoleiros e laranjas, bem como suas relações de trabalho e com a cidade de Foz do Iguaçu, constituída a partir do comércio estabelecido na fronteira Brasil - Paraguai. Por meio desse enfoque, propus-me entender discutir as relações desses sujeitos com os órgãos públicos e privados (tais como A Receita Federal, Prefeitura, imprensa jornalística), partindo das dinâmicas constituída por eles, suas estratégias de trabalho forjadas, bem como os significados estabelecidos com relação atividade e a cidade. Propus-me compreender, também, como esses sujeitos se constituem enquanto classe, a partir das suas trajetórias, migrações, experiências individuais e coletivas, bem como suas formas próprias de viver, inserir, agir e interpretar o espaço urbano. Enfim, desvendar as dinâmicas dos sacoleiros e laranjas revela-se também uma forma de situar as memórias desses trabalhadores como fazendo parte do processo de afirmação e construção dos espaços sociais, reafirmando sua condição de agentes produtores na cidade de Foz do Iguaçu.
|
69 |
Validering av Social Competence Scale för observatörer i ett stickprov från den svenska förskolanKvamme, Ylva January 2014 (has links)
Likvärdigheten i den svenska skolan har på senare år försämrats. Social och emotionell kompetens har visat sig ha stor betydelse för skolframgång, psykisk hälsa och förekomst av problembeteenden och interventioner som stärker dessa kan vara ett sätt att åtgärda skolans problem. För utvärdering av sådana interventioner behövs validerade mätinstrument. Denna studies syfte var att undersöka validiteten hos Social Competence Scale för observatörer (SCO). Skalan används vid en standardiserad leksituation för att skatta barns sociala och emotionella kompetens. En explorativ faktoranalys genomfördes på SCO, samt korrelationer med två kriteriemått, utifrån hypotesen att finna positiva korrelationer. Dessa två var Social Competence Scale för lärare, en lärarenkät som ligger till grund för SCO, och Assessment of Childrens Emotions, en uppgift där barn ska identifiera känslor utifrån ansiktsbilder. I likhet med tidigare analyser av instrumentet fann studien en faktorstruktur med en faktor. Inga signifikanta korrelationer mellan SCO och de två kriteriemåtten erhölls. Skalan behöver studeras vidare för validering. Bortfall och förändringar i skalans administration under datainsamlingen gör att resultaten bör tolkas försiktigt.
|
70 |
Long-term vegetation monitoring – a 33 year record from table mountainEmms, Paul Ivor January 2013 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / Nearly 40 years ago McLachlan and Moll highlighted the need for a well-defined path system on the Western Table of Table Mountain in the immediate vicinity of the Upper Cable Station (UCS). At that time the numbers of people using the cableway was heavily impacting the vegetation on the Western Table, particularly in the vicinity of the UCS. This prompted a study by Coley (1977) to assess the long-term impacts of trampling in this area. In order to monitor changes in the vegetation through time Coley set up 12 permanently marked plots (each ~4x4 m), arranged at increasing distances from the UCS. Plot positions were
carefully selected so that the effects of trampling on the vegetation could be measured at various points (distance being a surrogate for trampling intensity). Field observations in 1977 revealed that Mountain Fynbos vegetation was heavily impacted by cableway tourists. Furthermore the vegetation was most damaged closest to the UCS, with a sharp decrease in damage with increasing distance from the station. In order to monitor the vegetation change Coley used aerial photographs of permanently marked plots, so that visual comparisons of species cover, condition and composition could be made over time. The vegetation was then assessed in terms of percentage cover, and percentage damaged for each plot. My study marks the fifth time data were collected since Coley (1977) and the results show that there has been a marked improvement in vegetation quality since the construction of well-defined paths and a concerted effort by managers to ensure tourists do not leave the paths; which has greatly reduced trampling since the 1997 upgrade. The implications of this study provided evidence of the importance of restricting iv tourist traffic in areas that are regularly visited and, therefore, highly impacted. It also shows that denuded fynbos is resilient and does recover over time, provided that the substrate is not eroded too heavily by trampling. Finally, I present several management recommendations, of which the most controversial, albeit important, is for a rotational block burn programme on the Western Table; since fire is a keystone ecological process that has been absent of the Western Table for at least 80 to 90 years.
|
Page generated in 0.0245 seconds