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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.
241

Analyse de l'impact des propriétés radiatives de façades pour la performance énergétique de bâtiments d'un environnement urbain dense

Doya, Maxime 08 July 2010 (has links) (PDF)
L'interaction des phénomènes de transfert de chaleur et de masse dans un tissu urbain avec les apports anthropiques participent à l'îlot de chaleur urbain et à la dégradation de la performance énergétique des bâtiments. L'objectif de cette étude est de définir l'impact de la modification des propriétés radiatives aux façades des bâtiments qui peut être réalisée par l'utilisation de revêtements sélectifs colorés récemment développés pour les toitures. Les flux sensibles et l'impact sur les bâtiments sont étudiés pour une morphologie caractéristique des milieux urbains denses, la rue canyon. Un suivi expérimental mené sur des surfaces élémentaires de propriétés radiatives différentes nous a permis de développer par une méthode d'optimisation un procédé de détermination simultané du coefficient de convection et des absorptivités solaires effectives sur la période de mesure. L'utilisation de peintures sélectives dans la configuration canyon retenue est ensuite analysée expérimentalement. Pour cela une maquette (1/10ème) de scène urbaine a été conçue sur la base de 5 rangées de cuves de béton creux qui ont fait l'objet de mesures de températures et de flux radiatifs. Dans un premier temps, le traitement de deux mois de mesures a permis de caractériser les évolutions de champs de températures liés à cette forme urbaine. Par la suite, trois configurations de propriétés radiatives aux façades ont été étudiées simultanément et ont permis d'analyser les modifications spécifiques sur les champs de température, de sur-faces et d'air. Afin d'estimer les économies d'énergie réalisables sur un bâtiment réel ainsi que l'impact sur son environnement proche, une étude paramétrique des revêtements de façade et de la chaussée a été effectuée par des simulations de l'interaction du bâti et du micro-climat. Les méthodes et expériences établies dans cette étude nous permettent d'envisager le développement du traitement des façades et de la caractérisation de leurs performances globales.
242

Sources and concentration distribution of polycyclic aromatic hydrocarbons in sediment cores of Fangliao submarine canyon

Yang, Fu-yun 01 July 2009 (has links)
This study investigated the concentration distributions of polyclic aromatic hydrocarbons (PAHs) in the sediment cores collected from Fang-Liao submarine canyon. Chemical fingerprinting techniques and statistical analysis were applied to delineate the possible sources of the PAHs in deposited sediment core samples. It is noteworthy that all cores were not dated; therefore the deposition age could not estimate from the depth of deposition directly. The average concentrations of polyclic aromatic hydrocarbons (£U51PAHs) were found ranged from 229 to 638 (ng/g dry wt) in the sediment cores in Fang-Liao submarine canyon. In addition, the low molecular weight PAHs (2-3 ring PAHs) were found dominant in the PAH composition pattern of most samples. Total PAH concentrations were significantly correlated with total organic carbon (TOC) in all the sediment cores. Compared with sediment quality guidelines (SQGs), the PAH concentrations of all sediment samples were lower than those outlined in the criteria, that suggests no evident adverse biological effects caused by PAHs. Results also showed that total PAH concentration of surface sediments (0-2 cm) decreased with the water depth. Identification of PAHs sources suggests that all up-cores were dominated by petrogenic sources, but all down-cores except for S17 and S18 were dominated by pyrogenic sources or mixed sources. In contrast, biogenic sources were found dominant in S17 and S18 as they were characterized by higher ratio of perylene/£Upenta-PAHs(%). Compared with literature, the sediment cores of Fang-Liao submarine canyon were moderately polluted with PAHs. Analysis of diagnostic ratios and hierarchical cluster analysis (HCA) as well as principal component analysis (PCA) all indicate PAHs sources of Fang-Liao submarine canyon were mainly from petroleum and petroleum combustion sources for site of S3,S5,S7,S8 and S17; while pyrogenic or mixed sources for site of S1,S2,S9,S18 and S33.
243

LIVING ON THE EDGE: RETHINKING PUEBLO PERIOD: (AD 700 – AD 1225) INDIGENOUS SETTLEMENT PATTERNS WITHIN GRAND CANYON NATIONAL PARK, NORTHERN ARIZONA

Mink, Philip B., II 01 January 2015 (has links)
This dissertation challenges traditional interpretations that indigenous groups who settled the Grand Canyon during the Pueblo Period (AD 700 -1225) relied heavily on maize to meet their subsistence needs. Instead they are viewed as dynamic ecosystem engineers who employed fire and natural plant succession to engage in a wild plant subsistence strategy that was supplemented to varying degrees by maize. By examining the relationship between archaeological sites and the natural environment throughout the Canyon, new settlement pattern models were developed. These models attempt to account for the spatial distribution of Virgin people, as represented by Virgin Gray Ware ceramics, Kayenta as represented by Tusayan Gray Ware ceramics, and the Cohonina as represented by San Francisco Mountain Gray Ware ceramics, through an examination of the relationships of sites to various aspects of the natural environment (biotic communities, soils, physical geography, and hydrology). Inferences constructed from the results of geographic information system analyses of the Park’s legacy site data, indicate that Virgin groups were the first to arrive at the Canyon, around AD 700 and leaving around AD 1200. They practiced a split subsistence strategy, which included seasonal movements between maize agricultural areas in the western Inner Canyon and wild resource production areas in the pinyon-juniper forests on the western North Rim plateaus. The Kayenta occupied the North Rim, South Rim and Inner Canyon, throughout the entire Pueblo Period. Their subsistence system relied heavily on wild resource production on both rims supplemented by low-level maize agriculture practiced seasonally on the wide deltas in the eastern Inner Canyon. The Cohonina were the last to arrive and the first to leave, as they occupied the Canyon for about 300 years from AD 800–1100. They were the most prolific maize farmers, practicing it in the Inner Canyon near the mouth of Havasu Creek, but still seasonally exploiting wild resource on the western South Rim. Based on my interpretations, use of the Canyon from AD 700-1225, is viewed as a dynamic interplay between indigenous groups and their environment. As they settled into the Canyon and managed the diverse ecology to meet their subsistence needs.
244

The geology and geochemical case history of the Juniper Canyon copper-molybdenum prospect, Pershing County, Nevada

Butler, Edwin Farnham, Jr. January 1981 (has links)
No description available.
245

ABSOLUTE POLLEN FREQUENCIES APPLIED TO THE INTERPRETATION OF HUMAN ACTIVITIES IN NORTHERN ARIZONA

Kelso, Gerald Kay, 1937- January 1976 (has links)
No description available.
246

Water Bottle Canyon Traditional Cultural Property Study Photograph Collection

Stoffle, Richard W., Van Vlack, Kathleen, O'Mara, Nathaniel 05 September 2013 (has links)
These photographs offer illustrations of the people, places, and resources of Water Bottle Canyon. These photographs were taken during the 2004 Traditional Cultural Property Study.
247

So Much for Beauty: Realizing Participatory Aesthetics in Environmental Protection and Restoration

Stroud, Mary January 2013 (has links)
This study analyzes visual artifacts from three case studies, Hetch Hetchy Valley, Echo Park, and Glen Canyon, in order to contribute to scholarship devoted to environmental visual rhetoric. Through these studies, I address connections between aesthetics and environmental ethics and challenge scholarship that argues mainstream preservationist perspectives have adhered to an anthropocentric ideological paradigm. Grounding my argument in philosopher Arnold Berleant's notion of participatory aesthetics and deploying social semiotics and media analysis methodologies, I propose that two particular aesthetic grammars have been at use in mainstream environmental rhetorics, that which I call the wilderness sublime and the wilderness interactive. Present in the late 19th and early 20th centuries, and well documented in existing scholarship, the aesthetic of the wilderness sublime has operated through strict dichotomies between nature and culture that promote reductive views of human relationships with nature. Conversely, I argue that the aesthetic of the wilderness interactive, discoverable in artifacts from the mid-20th century to today, has worked to resist these dichotomies through the use of participatory elements that feature humans and nature in what Berleant calls a "relationship of mutual influence," falling within a more ecocentric ideological view. Through my analysis, I extend Berleant's theoretical application from photography to websites to argue that web-based rhetorics contain distinct potential for the realization of participatory features. In particular, I focus on the aesthetic, technological, social, archival, subjective, and epistemological dimensions proposed by Melinda Turnley to discuss dialogic features of websites that can work to engage diverse stakeholders. Through my findings, I offer a visual analysis heuristic that can be used to discover participatory aesthetics within visual artifacts and resist dualistic views of the environment. Likewise, I present a user analysis heuristic that can help identify targeted stakeholders and recognize participatory aesthetics within websites. Ultimately, this study answers the call of environmental aesthetics to address the realization of perceptual norms that offer more ethical conceptions of human relationships with nature, and it extends this focus into the digital environment to discuss the ability of web design and aesthetics to promote generative stakeholder dialogue in environmental protection and restoration.
248

Paa’oatsa Hunuvi (Water Bottle Canyon)- A Traditional Cultural Property, Presentation for the Great Basin Anthropological Conference

Stoffle, Richard W. 19 October 2006 (has links)
This paper was given at the Great Basin Anthropological Conference in Las Vegas, Nevada in 2006. This talk presents findings from the 2004 Water Bottle Canyon Traditional Cultural Property Study.
249

Les foraminifères benthiques de la marge portugaise : Impact des apports organiques sur la densité, la biodiversité et la composition des faunes

Phipps Mark, Daniel 28 August 2012 (has links) (PDF)
Les faunes de foraminifères vivants (colorés au Rose Bengale) ont été analyses à 8 stations le long d'un transect bathymétrique (282-4987 m) sur la marge portugaise. Du plateau externe vers la plaine abyssale, une succession d'assemblages est trouvée en relation avec la diminuation du niveau trophique. La densité des faunes, la richesse spécifique et la diversité diminuent plus rapidement avec la profondeur pour les foraminifères carbonatés que pour les foraminifères agglutinés. Aux sites mésotrophes et oligotrophes les espèces carbonatées sont généralement limitées au centimètre supérieur. Les espèces agglutinées sont peu diversifies à la station la moins profonde, à cause d'une competition avec les espèces carbonatées et la pénétration d'oxygène très faible. Aux stations plus profondes, leurs diversité et ALD10 augmentent en réponse à la penetration d'oxygène et la bioturbation plus importantes. Aux stations les plus profondes, les foraminifères agglutinés montrent une faible diversité, et sont de nouveau limités à la surface du sediment. Un transect latitudinal regroupe 7 autres stations, de pente ouverte et de canyon ouvert, à une profondeur d'environ 1000 m. Dans les canyons sousmarins, les densités des faunes, dominées par des espèces endopéliques intermédiares et profondes, sont largement supérieures, en accord avec des teneurs en CPE plus élévées. Dans le canyon de Nazaré, des faibles teneurs en oxygène causent une diversité minimale. La variabilité temporelle apparait ètre beaucoup plus importante dans les canyons sous-marins, où des perturbations sédimentaires et les apports organiques sont maximaux.
250

Shíyazhi Sha'a'wéé' Diné Nilih. A'daayoo nééhlagoh. My Child, You Are Diné

January 2011 (has links)
abstract: Early childhood is a special and amazing period in a child's development. It is a period during which all facets of a human being-cognitive, linguistic, physical, emotional, social, and spiritual--are rapidly developing and influenced by a child's interactions with her socializers and environment. Fundamentally, what happens during this critical period will influence and impact a child's future learning. Much of what is known about children's development comes from research focusing primarily on mainstream English speaking children. However, not much that is known about Indigenous children and their early period of child development. Therefore, this thesis research focused on Diné children and their early childhood experiences that occur during the fundamental time period before Diné children enter preschool. It also examines the contemporary challenges that Diné parents and other cultural caretakers face in ensuring that Diné infants and young children are taught those important core elements that make them uniquely Diné. The research questions that guide this thesis are: 1.What do Diné people believe about children and their abilities? 2.What do Diné children need to learn in order to become Diné? 3. What are the Diné childhood rearing beliefs and practices? 4. Why aren't Diné parents and grandparents teaching their children how to be Diné? Findings reveal an early childhood experience in which children are viewed as true explorers and highly intelligent, inquisitive learners and included as integral participants and contributors to the family and community. This thesis concludes with a discussion of the multidimensional transitions, such as the shift from the Diné language to English in Diné homes and communities that have occurred in the Diné way of life and how they have impacted how Diné children are socialized. Creative alternatives for increasing Diné childhood speakers on and off the Navajo reservation are also considered. / Dissertation/Thesis / M.A. Curriculum and Instruction 2011

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