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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.
141

Maya Use And Prevalence Of The Atlatl: Projectile Point Classification Function Analysis From Chichen Itza, Tikal, And Caracol

Ciofalo, Andrew J 01 January 2012 (has links)
Multiple scholars have briefly discussed the Maya use of the atlatl. Yet, there has never been a decisive encompassing discussion of prevalence and use of the atlatl in the Maya region with multiple lines of support from iconographic and artifactual analyses. This thesis explores the atlatl at Chichén Itzá, Tikal, and Caracol Maya sites to prove that atlatl prevalence can be interpreted primarily based on projectile point “classification function” analysis with support from iconographic and artifactual remains. The classification functions are derived from creating mutually exclusive groups of dart points and arrow points by using discrete functional analysis. Discerning between dart and arrow points can be completed with a high degree of accuracy based on maximum shoulder width of lithic points in an assemblage. Because the atlatl and bow complexes have been primarily constructed of perishable materials, the best method to determine the prevalence of atlatl use is by identifying the launcher based on projectile point identification. Using a cross-site comparison of projectile point size, the Maya use and prevalence of the atlatl will be elucidated
142

Long term effects of wet site timber harvesting and site preparation on soil properties and loblolly pine (Pinus taeda L.) productivity in the lower Atlantic Coastal Plain

Neaves, Charles Mitchell III 22 May 2017 (has links)
Short term studies have suggested that ground based timber harvesting on wet sites can alter soil properties and inhibit early survival and growth of seedlings. Persistence of such negative effects may translate to losses in forest productivity over a rotation. During the fall and winter of 1989, numerous salvage logging operations were conducted during high soil moisture conditions on wet pine flats in the lower coastal plain of South Carolina following Hurricane Hugo. A long-term experiment (split-plot within an unbalanced randomized complete block design) allowed assessment of long term effects of rutted and compacted primary skid trails and subsequent site preparation on soil properties and loblolly pine (Pinus taeda L.) productivity. The experiment had 12 blocks, four levels of site preparation as the whole plot factor (bedding, disking with bedding, disking, and no site preparation), and two levels of traffic as the subplot factor (primary skid trail, no obvious traffic). After 23 years, bedding and disking with bedding treatments effectively enhanced soil physical properties and stand productivity via promoting greater survival and stocking, but had little effect on the size of individual trees relative to disking and no site preparation treatments. Primary skid trails significantly reduced the size of individual trees, but had no appreciable long term effects on soil properties or stand productivity after 23 years. The study suggests that bedding is the most efficient practice to enhance soil properties, seedling survival, and stand productivity on wet sites. However, site preparation is not necessary for these soils and sites, if strictly intended to restore soil properties and stand productivity in primary skid trails. Reduction in individual tree sizes on primary skid trails emphasizes benefits in minimizing the spatial extent of disturbance. / Master of Science
143

The Geologic and Archaeological History of the Dickie Carr Site 41PR26

Byers, Johnny A. 05 1900 (has links)
This thesis is an analysis and synthesis of the geologic and archaeological history of the Dickie Carr site, 41PR26, on Mill Creek in north central Texas. Included are analyses of the stratigraphy, sedimentary environments, and soils of the locality. A regional comparison is made with respect to the Late Quaternary geology of the upper Trinity River basin, Texas to interpret the geologic data. Two stratigraphic units were identified that record the Pleistocene-Holocene transition. The buried lower unit is comprised of terrace, floodplain, and channel deposits with extensive pedogenesis. The unit is Late Pleistocene in age and contains the remains of Mammuthus columbi. The upper stratigraphic unit is comprised of terrace and floodplain sediments with well-expressed pedogenesis. The unit is Early Holocene in age with Late Paleoindian and Late Archaic occupations. The archaeological components are compared and contrasted with documented sites from the Elm and East Forks of the Trinity River. The occupations are examined in a geoarchaeological context. The Late Paleoindian occupation is post-depositional and located in terrace deposits. The Late Archaic occupation is syndepositional and located in floodplain deposits.
144

An evaluation of criteria proposed to reauthorize the cleanup of superfund sites : case studies from EPA's Region X

Williamson, Gina Denise 18 May 1995 (has links)
Graduation date: 1996
145

A Decision Support Tool For Conceptual Site Model Development At Contaminated Sites

Buyuker, Beril 01 September 2009 (has links) (PDF)
A conceptual site model (CSM) is simply a description of the environmental conditions at a contaminated site and surrounding area, which provides all interested parties with a vision of the site. CSM mainly identifies the source-pathway&amp / #8208 / receptor linkage to guide for effective site characterization, risk assessment and remedial investigations. Development of CSM is complicated because it is &lsquo / case specific&rsquo / and there is no single route to follow during decision making concerning the contaminated site. Moreover, type and extent of information needed varies according to size and level of contamination and site heterogeneity. The objective of this study is to develop a decision support tool that guides the site assessors during identification of possible decision routes that can be encountered / the procedure to be followed / and the information and data to be collected at each stage. This tool also introduces interactions between CSM andsampling strategies designed for various purposes. Developed decision support tool adapts to each specific contaminated site. Furthermore, a detailed review of sampling strategies is presented as a guidance for site assessors. The decision support tool is equipped with standardized tools used for CSM development, i.e. information/data collection forms, illustrative tools and exposure pathway diagram. Information on site, geology, hydrogeology, contamination source, contaminants and receptors is collected via CSM form. Illustrative tools may vary from very simple site sketches to very complex 3D drawings depending on the needs of the specific contamination cases. Exposure pathway diagram (EPD) is used to identify all transport mechanisms and potential exposure pathways. EPD is embedded into a user&amp / #8208 / friendly decision assistance tool based on Microsoft Excel and Visual Basic for Applications. The applicability and utility of the decision support tool was tested using two case studies. Case study applications indicated that the developed methodology satisfies the objectives aimed in this study.
146

Suivi de l'efficacité de trois bio-recouvrements d'oxydation passive du méthane installés sur un site d'enfouissement

Askri, Mohamed Ali January 2008 (has links)
Les bactéries méthanotrophes, qui existent dans les recouvrements des sites d'enfouissements, peuvent oxyder le CH[indice]4 émis par ces sites. La capacité de ces recouvrements à atténuer le CH[indice]4 dépend à la fois des propriétés physiques et chimiques du matériau, du débit du biogaz et de sa composition, et des paramètres climatiques. Ces recouvrements, communément appelé Biorecouvrements d'oxydation passive de méthane (BOPM), pourraient venir en complément d'autres systèmes tels que les puits de captage de biogaz ou encore pourraient servir sur les sites ne disposant d'aucun système de récupération des biogaz. Cette possibilité de réduction des émissions de CH[indice]4 a motivé des travaux de construction et de suivi sur le site d'enfouissement de Saint-Nicéphore (Québec, Canada). Vous trouverez d'abord dans ce mémoire l'analyse d'une méthode de calcul de l'efficacité des BOPMs à oxyder le CH[indice]4 et une comparaison des taux d'efficacités entre 2 BOPMs de porosités différentes. Cette méthode de calcul est basée sur les profils de concentration des gaz et le rapport N[indice]2 /O[indice]2 pour déterminer la quantité d'oxygène qui a migré dans le sol avant d'être consommé. Plusieurs questions ont été soulevées lors de cette analyse dont, entre autres, la constance du rapport N[indice]2 /O[indice]2 dans le sol et l'effet de la respiration du compost sur les calculs d'efficacité. Quant à la comparaison entre les 2 BOPMs, les résultats ont montré qu'en augmentant la porosité de mise en place du substrat, la pénétration de l'oxygène était favorisée et, par conséquence, son efficacité à oxyder l'était également. Vous trouverez ensuite une observation de l'effet des changements climatiques sur le comportement des BOPMs de compositions différentes pendant une longue période et une étude de l'effet de l'alternance jour/nuit sur leurs efficacités lors de cycles très courts. Pour de longs cycles, il a pu être constaté qu'après le dégel du sol, les quantités de méthane libérées ont été très importantes et elles ont eu un impact direct sur la performance des BOPMs, que l'augmentation du rapport diffusion/advection a eu pour conséquence une nette amélioration de l'efficacité de la BOPM et que les bactéries méthanotrophes ont été plus influencées par les variations de température que par ces valeurs (températures). Pour les cycles courts, les variations journalières de température à 0,10 mètre de la surface du sol ont été suivies de considérables variations des concentrations de CH[indice]4 . Vous trouverez enfin, une étude complémentaire sur l'importance de la croûte superficielle sur l'efficacité des recouvrements. Les résultats des essais de perméabilité à l'air et les courbes de rétention en eau qui ont servi à caractériser le substrat y sont succinctement présentés.
147

Homol'ovi II: Archaeology of an Ancestral Hopi Village, Arizona

January 1991 (has links)
Homol'ovi II is a fourteenth-century, ancestral Hopi pueblo with over 700 rooms. Although known by archaeologists since 1896, no systematic excavations were conducted at the pueblo until 1984. This report summarizes the findings of the excavations by the Arizona State Museum of five rooms and an outside activity area, which now form the core of the interpretive program for Homolovi Ruins State Park. The significant findings reported here are that the excavated deposits date between A.D. 1340 and 1400; that nearly all the decorated ceramics during this period were imported from villages on the Hopi Mesas; that cotton was a principal crop which probably formed the basis of Homol'ovi II's participation in regional exchange; that chipped stone was a totally expedient technology in contrast to ground stone which was becoming more diverse; and that the katsina cult was probably present or developing at Homol'ovi II. These findings from the basis for future excavations that should broaden our knowledge of the developments taking place in fourteenth-century Pueblo society connecting the people whom archaeologists term the Anasazi with those calling themselves Hopi.
148

Högläggning eller harvning : En jämförande studie av planteringspunkter och markpåverkan vid olika terrängförhållanden. / Mounding or disc trenching? : A comparing study of planting spots and terrain impact in different types of terrain.

Karlsson, Josef January 2016 (has links)
A comparing study of planting spots and terrain impact in different types of terrain.
149

Bio-engineering and genetic manipulation of ovine interleukin-2

Gossner, Anton Gerhard January 1998 (has links)
No description available.
150

Molecular analysis of antigenic variation in fusion glycoprotein of respiratory syncytial virus

Conor, Alyson Lloyd January 1998 (has links)
No description available.

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