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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.
411

Passenger Volumes Post-accession to the European Union: Signs of Southwest Airlines' Model in Central and Eastern Europe

January 2012 (has links)
abstract: In 2004 the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Poland, Slovakia, and Slovenia joined the European Union (EU) as part of the EU's greatest enlargement to date. These countries were followed by Bulgaria and Romania in 2007. One benefit of joining the EU was the freedom for residents in the new EU member states to migrate to western European nations, notably the United Kingdom (UK). A result of this new freedom was an increased need for air travel. The intersection of the expansion of the EU with the introduction of low-cost airline service was the topic addressed in this study. Yearly traffic statistics obtained from the UK Civil Aviation Authority were used to formulate a trend line of passenger volume growth from 1990 to 2003. Through a time series regression analysis, a confidence interval was calculated that established that, beginning with the year 2004, passenger volumes exceeded the probable margin of error, despite flat population growth. Low-cost carriers responded to these market conditions through the introduction of new flights across the region. These carriers modeled themselves after Southwest Airlines, a strategy that appeared to be more effective at meeting the needs of the post-accession travel boom. The result was a dramatic rise in both passenger volumes and low-cost airline routes in an east-west direction across the continent. / Dissertation/Thesis / M.S.Tech Technology 2012
412

O transporte ferroviário no nordeste brasileiro e o potencial de desenvolvimento do sudoeste do Estado do Piauí / The railway transport in the brazilian northeast and the State of Piaui southwest development potential

Lopes, José Carlos Raulino [UNESP] 04 January 2016 (has links)
Submitted by JOSÉ CARLOS RAULINO LOPES (raulino@ifpi.edu.br) on 2016-02-29T18:32:12Z No. of bitstreams: 1 Tese formatada e revisada para impressão - Raulino.pdf: 5371264 bytes, checksum: 23c7c81dd61e8a9ec263a44297c94c08 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-02-29T19:28:03Z (GMT) No. of bitstreams: 1 lopes_jcr_dr_rcla.pdf: 5425047 bytes, checksum: 42ac4af121a84820fbf5ebd3d65cd41c (MD5) / Made available in DSpace on 2016-02-29T19:28:03Z (GMT). No. of bitstreams: 1 lopes_jcr_dr_rcla.pdf: 5425047 bytes, checksum: 42ac4af121a84820fbf5ebd3d65cd41c (MD5) Previous issue date: 2016-01-04 / Tem-se, no processo de territorialização, desterritorialização e reterritorialização, o caminho escolhido para compreender um pouco da configuração espacial construída no nordeste do Brasil e a constituição da sua malha ferroviária. Em 1997, a malha ferroviária do nordeste foi concedida à Companhia Ferroviária do Nordeste (CFN), hoje Transnordestina Logística S.A. (TLSA), por meio do Programa Nacional de Desestatização (PND). Portanto, investigar a influência do transporte ferroviário no nordeste, enfatizando-se seu histórico, avaliando-se o processo de desestatização ocorrido em 1997 e suas perspectivas, assim como os resultados desta nova gestão, pós-desestatização (sob a iniciativa do capital privado), e as expectativas de desenvolvimento do sudoeste do estado do Piauí. Ressalta-se que, antes do recente e exponencial crescimento do agronegócio nos cerrados nordestinos, sobretudo no sudoeste do estado do Piauí, a região era apontada como sinônimo de pobreza, com baixos índices de produtividade agrícola, além de falência dos municípios. Para agravar, os poderes públicos se mostravam desarticulados ou descomprometidos com as novas demandas, gerando forte migração para as capitais, potencializando estes problemas. Hoje, porém, o cenário vem se transformando, sobretudo após o início da construção da estrada de ferro denominada Nova Transnordestina, que tem gerado grande expectativa, sendo apontada como vetor de desenvolvimento socioeconômico do sudoeste do estado do Piauí. Tal região vem sendo indicada como a última fronteira agrícola do país, situada em uma área maior, denominada MATOPIBA, a qual é formada por parte dos estados do Maranhão, Tocantins, Piauí e Bahia, referência em agroindústria, sobretudo da soja. / It has been in the process of territorialization, deterritorialization and repossession, the path chosen to understand some of the spatial configuration built in northeastern Brazil and the establishment of its rail network. In 1997, the railway network of the northeast was awarded to Northeast Railway Company - CFN today Transnordestina S.A. Logistics - TLSA, through the National Privatization Program - PND. Therefore, to investigate the influence of the railway in the northeast, emphasizing its history, evaluating the privatization process occurred in 1997 and its prospects, as well as the results of this new management, post privatization (under the initiative of private capital) and southwest of the development expectations of Piaui state. It is noteworthy that before the recent exponential growth of agribusiness in the northeastern savannahs, particularly in the southwestern state of Piaui, the region was identified as synonymous with poverty, low levels of agricultural productivity, as well as failure of municipalities. Compounding the government is showing inarticulate or unengaged with the new demands, generating strong migration to the capital, increasing these problems. Today however, the scenario is changing, especially after the start of construction of the railway called New Transnordestina, which has raised great expectations, being singled out as a vector of socio-economic development of the southwestern state of Piaui, pointed region as the last agricultural frontier of the country, which is situated in a larger area called MATOPIBA, formed by the states of Maranhão, Tocantins, Piauí and Bahia, a reference in agribusiness, especially soy.
413

Vesicular Basalt Provisioning Practices Among the Prehistoric Hohokam of the Salt-Gila Basin, Southern Arizona

January 2014 (has links)
abstract: This study evaluates five different hypotheses potentially accounting for the prehistoric movement of vesicular basalt during the Hohokam occupation of the Salt-Gila Basin (ca. A.D. 700-1450): 1) direct procurement; 2) direct exchange; 3) down-the-line exchange; 4) market exchange; and 5) elite-controlled exchange. The plausibility of each hypothesis is assessed by examining the relative frequency of different vesicular basalt source types at sites as related to the geographic distance from their source; intra-site variance in vesicular basalt source type diversity; inter-site variance in vesicular basalt source type diversity; and temporal specificity and continuity in source preference. The study sample is comprised of 484 vesicular basalt artifacts recovered from nine Hohokam sites: Casa Grande, Gila Crossing, the Hospital Site, La Plaza, Las Colinas, Los Hornos, Lower Santan, Pueblo Grande, and Upper Santan. Geographic provenance data for artifacts are generated by comparing their chemical composition to a geochemical reference database composed of more than 700 vesicular basalt raw material samples from 17 different source areas in the Salt-Gila Basin. Geochemical data for both artifact and raw material samples were collected using a portable X-ray fluorescence spectrometer and a newly developed sampling procedure that provides an efficient, reliable, and nondestructive means of analysis. The results of the hypothesis testing found that direct procurement is a possible material provisioning practice for perhaps only a small number of households in the Salt-Gila Basin; specifically those located less than 10 km from a vesicular basalt outcrop. Direct exchange is also an unlikely explanation, though it cannot be rejected outright. The other exchange hypotheses, down-the-line, market, and elite-controlled exchange, as defined in this study, are all rejected as possible explanations. From these results, a new model of Hohokam vesicular basalt provisioning practices is developed for future testing. This model posits that vesicular basalt groundstone tools were produced by specialists in a handful of locations during both the Preclassic and Classic periods, and that finished tools were acquired through workshop procurement or local distributers. The implications of these findings for understanding the organization of Hohokam domestic and political economies are also discussed. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2014
414

Flora of the Upper Verde River, Arizona

January 2015 (has links)
abstract: The Upper Verde River of central Arizona flows through a landscape of complex geology at the meeting of seven biotic communities and three physiographic provinces. This has resulted in notably diverse flora and fauna and a hub of rare and endemic plant species. The river has sustained cultures since pre-history, however current regional water use is predicted to diminish streamflow over the next century. Prior to this project, no floristic inventory had been conducted along any section of the Verde. The purpose of this study was to develop a Flora of the Upper Verde River, with the goals of documenting rare and endemic species, the composition and abundance of wetland plants, and the factors shaping plant diversity in the region. I made a total of 1856 collections and reviewed past collections to produce a checklist of 729 vascular plant taxa in 403 genera and 98 families. The most species-rich family is the Poaceae, followed by Asteraceae and Fabaceae. The flora includes 159 wetland taxa, 47 endemics, and 26 taxa of conservation concern, eight of which are Federally listed. Several new populations were found in these categories and of rarely-collected taxa including one state record, three county records and several range extensions. I report on the local status of several endemics, wetland taxa with limited distributions, and relict populations of a tepary bean (Phaseolus acutifolius) that were likely transported to the region and cultivated by pre-Columbian cultures. I categorize thirteen distinct plant communities, the most abundant being Pinyon/Juniper Woodland, Chihuahuan/Apacherian Scrub, and Riparian Deciduous Forest. Four primary factors influence floristic diversity of the Upper Verde region: 1) a location at the junction of three physiographic and floristic provinces—represented by co-occurrence of species with affinities to the Sonoran, Intermountain and Madrean regions, 2) geologic diversity—as distinct groups of species are associated with particular geologic types, 3) topographic and habitat complexity—allowing species adapted to disparate environments to co-occur, and 4) human introductions—since over 15% of the flora is composed of introduced species from Eurasia and several taxa were introduced to the region and cultivated by pre-Columbian cultures. / Dissertation/Thesis / Masters Thesis Plant Biology 2015
415

Social Boundaries and the Organization of Plain Ware Production and Exchange in 14th Century Central Arizona

January 2016 (has links)
abstract: In the proposed project I simultaneously and reflexively identify and characterize social boundaries in the archaeological record by examining material culture distributions in novel ways to re-assess the scale of the Verde Confederacy, a proposed regional-scale multi-settlement alliance in Late Prehistoric central Arizona. I focus on boundaries between entities larger than villages, but smaller than regions or culture areas. I propose three innovations to better accomplish these goals. First, unlike previous conceptualizations of social boundaries as monolithic, I argue that they are better conceived of as a heterogeneous, multi-faceted phenomenon. Second, I investigate social boundaries by examining multiple lines of evidence. Previous researchers have tended to focus on one category of data at the expense of others. Third, I associate boundaries with relational and categorical collective social identification. An alliance requires regular collective actions including communication and coordinated action between large groups. These actions are most likely to emerge among groups integrated by relational networks who share a high degree of categorical homogeneity. I propose a plain ware ceramic provenance model. Seven reference groups represent ceramic production in specific geographic areas. The reference groups are mineralogically and geochemically distinct, and can be visually differentiated. With this provenance model, I reconstruct the organization of utilitarian ceramic production and exchange, and argue that plain ware distribution is a proxy for networks of socially proximate friends and relatives. The plain ware data are compared to boundaries derived from settlement patterns, rock art, public architecture, and painted ceramics to characterize the overall nature of social boundaries in Late Prehistoric central Arizona. Three regions in the study area are strongly integrated by relational networks and categorical commonality. If alliances existed in Late Prehistoric central Arizona, they were most likely to emerge at this scale. A fourth region is identified as a frontier zone, where internal connections and shared identities were weaker. As seen among the League of the Iroquois, smaller integrated entities do not preclude the existence of larger social constructs, and I conclude this study with proposals to further test the Verde Confederacy model by searching for integration at a broader spatial scale. / Dissertation/Thesis / Doctoral Dissertation Anthropology 2016
416

Associações alimentares em peixes recifais, com destaque em espécies nucleares e seguidoras /

Sazima, Cristina. January 2006 (has links)
Resumo: Acompanhar animais em atividade alimentar constitui um modo comum de forragear para peixes recifais que formam associações alimentares interespecíficas. Os peixes "seguidores" acompanham animais "nucleares" para aproveitar itens alimentares expostos ou produzidos através da atividade do nuclear. Tais associações alimentares são comuns para diversos tipos de peixes e outros animais, ocorrendo em variadas áreas geográficas. Este tipo de associação alimentar foi estudado no arquipélago oceânico de Fernando de Noronha, Atlântico Sul Ocidental tropical. O presente trabalho é composto de cinco artigos científicos, dispostos em quatro capítulos. O primeiro capítulo descreve associações alimentares entre peixes recifais e tartarugas marinhas. O segundo capítulo caracteriza o comportamento alimentar versátil de uma espécie de peixe recifal ao seguir outras espécies de peixes. O terceiro capítulo é composto de dois artigos; o primeiro trata da espécie de peixe nuclear mais comum e importante no arquipélago, ao passo que o segundo artigo descreve a associação entre seguidores e uma espécie de peixe cuja família não constava como nuclear. O quarto capítulo constitui uma revisão geral sobre o tema, com informações sobre o grupo de animais, na maioria peixes recifais, que forma associações alimentares interespecíficas como nucleares e/ou seguidores. A série de artigos científicos, apresentada no presente trabalho, amplia o conhecimento sobre agrupamentos alimentares e história natural da ictiofauna recifal no Atlântico Sul Ocidental tropical, além de modificar a situação deste tipo de associação alimentar na literatura científica mundial. / Abstract: Following behaviour is a foraging mode commonly recorded for reef fishes during heterospecific feeding associations. The followers escort so called nuclear foraging fishes and other animals to capitalise on food items exposed or produced by the activity of the nuclear ones. Such foraging associations are widespread and recorded for several fish and other marine animal taxa and geographic areas. This foraging mode was studied at the oceanic archipelago of Fernando de Noronha, tropical Southwest Atlantic. The present work is composed of five scientific papers, organized in four chapters. The first chapter describes foraging associations between reef fishes and marine turtles. The second chapter characterizes the variable foraging modes of a reef fish species while following other fishes. The third chapter is composed by two studies, the first dealing with the commonest and most important nuclear fish in the archipelago, while the second one describes the association between followers and a fish species in a family not previously recorded as a nuclear. The fourth chapter is an overview about this topic, with information about the assemblage of animals, mostly reef fishes, which engage in interspecific foraging associations as nuclears and/or followers. This series of articles broadens our understanding about feeding assemblages and natural history of reef fishes in the tropical Southwest Atlantic, besides modifying the knowledge on this type of foraging association. / Orientador: Augusto Shinya Abe / Coorientador: Ivan Sazima / Banca: Carlos Eduardo Leite Ferreira / Banca: Érica Caramaschi / Banca: Julio César Garavello / Banca: Sergio R. Floeter / Doutor
417

Urban Development and Sustainable Water Management of Southwest Cities

January 2013 (has links)
abstract: Water is the defining issue in determining the development and growth of human populations of the Southwest. The cities of Las Vegas, Phoenix, Tucson, Albuquerque, and El Paso have experienced rapid and exponential growth over the past 50 years. The outlook for having access to sustainable sources of water to support this growth is not promising due to water demand and supply deficits. Regional water projects have harnessed the Colorado and Rio Grande rivers to maximize the utility of the water for human consumption and environmental laws have been adopted to regulate the beneficial use of this water, but it still is not enough to create sustainable future for rapidly growing southwest cities. Future growth in these cities will depend on finding new sources of water and creative measures to maximize the utility of existing water resources. The challenge for southwest cities is to establish policies, procedures, and projects that maximizes the use of water and promotes conservation from all areas of municipal users. All cities are faced with the same challenges, but have different options for how they prioritize their water resources. The principal means of sustainable water management include recovery, recharge, reuse, and increasing the efficiency of water delivery. Other strategies that have been adopted include harvesting of rainwater, building codes that promote efficient water use, tiered water rates, turf removal programs, residential water auditing, and native plant promotion. Creating a sustainable future for the southwest will best be achieved by cities that adopt an integrated approach to managing their water resources including discouraging discretionary uses of water, adoption of building and construction codes for master plans, industrial plants, and residential construction. Additionally, a robust plan for education of the public is essential to create a culture of conservation from a very young age. / Dissertation/Thesis / M.S. Applied Biological Sciences 2013
418

Whiting Events Off Southwest Florida: Remote Sensing and Field Observations

Long, Jacqueline 02 November 2016 (has links)
“Whiting” is a term used to describe a sharply defined patch of water that contains high levels of suspended, fine-grained calcium carbonate (CaCO3). These features are named for their bright (at times white) appearance when compared to surrounding waters, and have been found to occur globally, persisting for multiple consecutive days. Although whitings have been widely studied using chemical, biological, geological, and physical techniques, there has been little effort to document their spatio-temporal distributions in a systematic way, not to mention the lack of consensus on what generates whitings and allows them to persist for days to weeks at a time. In particular, although fishermen and aircraft pilots have reported whiting-like features off southwest Florida (e.g., a sighting off the Ten Thousand Islands was reported on October 29, 2013), there has been no targeted study on these features in this area. Therefore, the objective of this study is two fold: 1) to document the spatial-temporal distributions of whitings in southwest Florida (SWFL) coastal waters from 2003 through 2015 using satellite imagery to study how their occurrence is related to several environmental variables and 2) to conduct field and laboratory measurements to determine the particle composition and water characteristics in and outside the whiting features. To achieve objective one, a multi-year time series from 2003 through 2015 was developed over SWFL using Moderate Resolution Imaging Spectroradiometer (MODIS) observations. Customized processing was used in order to removed clouds and other artifacts and to delineate the surface whiting features. From this, statistics and distribution maps of whiting occurrence were generated. Annual mean whiting coverage peaked in 2011 (11 km2), when whiting reached a maximum daily visible coverage of 92 km2 on February 23. For the entire time series, the highest daily coverage observed was 126 km2 on December 6, 2008. Over all, whitings had higher spatial coverage during the spring and autumn, with 88% of all whiting coverage occurring within 40 km of the coastline. Images of average seasonal spatial distributions showed that over 90% of whitings located between 40 and 70 km of shore occurred specifically during the winter and autumn. A multivariate linear regression was performed, which found little to no correlation between annual whiting coverage and environmental factors such as sea surface temperature (SST), wind, and river discharge. This analysis was also applied to spatial distributions of whiting events within and outside of 20 km and 40 km from shore. The only statistically significant result was that of SST, as well as SST with river discharge and whiting events distributed more than 20 km from shore. In order to accomplish objective two, several field campaigns were conducted to collect in-situ data and water samples of pre-, post-, and occurring whiting event conditions to provide information on composition, driving forces, and variables that cannot be derived via satellites. Samples were collected for taxonomic identification, chemical analysis, bottom sediment grain size fractionation, in-situ remote sensing reflectance (Rrs), particle backscattering (bbp), chlorophyll-a concentration ([chl-a]), particulate absorption (ap), and gelbstoff (otherwise known as color dissolved organic matter, or CDOM) absorption (ag). Taxonomic identification of marine phytoplankton within whiting water revealed the presence of a dominant, small (<5 >μm), centric diatom species during a sampled whiting event. Through the use of scanning electron microscopy (SEM), these were identified as Thalassiosira sp. Amorphous to fully formed crystals of calcium carbonate were present, attached to cells of Thalassiosira sp., localized to the girdle bands. All other diatom species were devoid of similar growths. In comparing the waters within a whiting area to outside waters, no significant differences were found in ap, ag, nor [chl-a]. The carbonate parameters of whiting water differed from outside water, however due to low sample numbers these results are inconclusive. Average backscattering was twice as high within whiting waters compared to non-whiting water, and measured in-situ Rrs was higher at all wavelengths (400 – 700 nm) within whiting water, with a spectral shape similar to outside waters. Overall, this is the first time that SWFL whiting events have been characterized systematically using satellite imagery, field and laboratory as well as meteorological data to diagnose whiting causes and maintenance mechanisms. Although these results are inconclusive, they add new information to the existing literature on this phenomenon.
419

Discontinuous morphological traits of the skull as population markers in the prehistoric southwest

Birkby, Walter Hudson, 1931-, Birkby, Walter Hudson, 1931- January 1973 (has links)
No description available.
420

Traces of Existence: Evidence of Prehistoric Populations in the Cibola National Forest of New Mexico

Gregory, Teresa L. 12 1900 (has links)
Is there more we can learn about the movement of prehistoric Puebloan people during the A.D. 900–1400 time period? In those moments of time when small groups of people dispersed across the landscape and formed aggregated communities. Some of the answers lie in the generally understudied landscape of the federally protected Cibola National Forest in west-central New Mexico. This area is on the eastern periphery of a well-documented Zuni region, and preliminary archaeological site data revealed the potential to further that knowledge. During a 10-day pedestrian survey, 42 archaeological sites containing a variety of traditional Zuni and local Lion Mountain pottery types were recorded. The presence of these Puebloan peoples was confirmed through analysis of the ceramics using the accepted Stanley South Mean Ceramic Dating techniques. Patterns of site locations dating from the Pueblo II to Pueblo IV time period were evaluated using ESRI ArcGIS mapping software. Specific data analysis including nearest neighbor, euclidean distance, and least cost analysis were used to relate the archaeological sites to each other and to the Pueblo communities in the southwest. This recently discovered settlement area near Lion Mountain revealed remnants of past Zuni populations and is further evidence of the expansion of these prehistoric peoples. The pottery shreds discovered at those sites, along with the architecture and specific kiva types, links the distinctive aggregated Zuni and Lion Mountain Communities together and allows for further investigations to explore settlement organization, exchange networks, and a facet of other archaeological questions.

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