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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.
51

MED VISUELL UTGÅNGSPUNKT : En undersökning av en metodprövande och multimodal animations-workshop / With a Visual Point of View : A Study of a Method in a Multimodal Animation Workshop

Halvars Franzén, Olle January 2012 (has links)
År 1972 skickade NASA upp en rymdsond, kallad Pioneer 10, ut i rymden med en bild fastsatt på sondens utsida. Bilden var ett meddelande till utomjordiska varelser och illustrerade information om människan och jorden. Med bilden som en visuell utgångspunkt har jag designat en workshop för åtta gymnasielever i två olika grupper som fått i uppgift att skapa en animation att skicka upp i en rymdsond idag. Genom att omformulera den digitala berättelsens metod har jag velat undersöka hur deltagarnas process och animation kommer att formas om utgångspunkten är visuell.   Jag har utifrån mina didaktiska designval undersökt vad deltagarna har gjort för egna val, material och tillvägagångsätt de använt sig av. Under projektets gång har jag samlat in empiri i form av ljudupptagningar, filmmaterial, fotografier och fältanteckningar samt analyserat deltagarnas animationer. Genom att använda mig av den multimodala diskursanalysen som teori har jag fått en inblick i hur deltagarna genom förhandlingar i diskussioner tolkar tecken och bygger upp idéer. I analysen framkommer hur de kommunicerar genom olika resurser som bygger upp ramar för hur handlingen konstrueras i animationen. Handlingen, tematiken i animationen, har kretsat kring var vi bor i Vintergatan, evolutionen, fortplantning och klimatskillnader etc. Under en och en halv dag har deltagarna utifrån en idé gjort ett bildmanus, lärt sig alla moment och till sist animerat en kortfilm. Dessa animationer har jag valt att visa upp på vårutställningen på Konstfack som den gestaltande delen i mitt arbete. Jag har även formgivit en affisch som ringar in den didaktiska designen och deltagarnas arbete i processen.
52

Geochemical study of the Mesoproterozoic Belt-Purcell Supergroup, western North America : implications for provenance, weathering and diagenesis

Gonzalez-Alvarez, Ignacio Jose 04 January 2006
Provenance in the lower Belt-Purcell Supergroup is constrained based on geochemical systematics and chemical monazite ages of argillites and sandstones. Rare earth element (REE), Cr-Ni, and Th/Sc-Sc systematics is equivalent for both facies and consistent with a dominantly post-Archean source area. Detrital monazite chemical ages restrict major provenance for the Appekunny and Grinnell sandstones and argillites to Paleoproterozoic terranes at ~1800-1600 Ma, minor contributions at ~1600-1500 Ma, and marginal contributions from Archean terranes at ~2600, likely in Laurentia. Similar detrital age spectra for monazites of argillites and sandstones of the Appekunny Formation are consistent with a common provenance for the two facies.</p> <p>The Belt-Purcell sequence records three major diagenetic stages displayed in argillites and sandstones: (1) K-addition and rare earth element post-Archean upper continental crust (PA-UCC)-like pattern; (2) a stage characterized by heavy REE enrichment relative to light REE and HFSE fractionation, and U and Ce mobility; and (3) local dolomitization with REE and high field strenght elements (HFSE) mobility. REE and HFSE mobility are interpreted as the result of oxidized alkaline brines developed by dissolution of evaporites. Monazites from the Appekunny and Grinnell formations differ compositionally and texturally in two groups. Rounded or inclusions with ages >~1400 Ma, interpreted as detrital, have higher Th2O, Y2O3 and lower LREE/HREE contents than euhedral individual monazite grains with chemical ages <~1400 Ma that posses opposed compositional characteristics, and viewed as diagenetic. Monazites that span <~1400 to 300 Ma could be the result of basinal brine activity during stages (2) and (3). </p> <p>Chemical index of alteration (CIA) for argillites and sandstones, corrected for a diagenetic K-addition average 73 and 66 respectively. These results, coupled with correlation of CIA with Eu/Eu*, low K/Cs ratios, and low Sr, Ca, and Na relative to PA-UCC, could be interpreted as the result of an moderate weathered provenance in a hot, wet climate being drained by a large-scale river system. Presence of minor pristine feldspars lowers the CIA values, and may signify minor contributions from proximal source with short-river transport under the arid to semi-arid climate in the depositional setting. Moderate to intense weathering of the larger provenance may be associated with elevated levels of atmospheric CO2 degassed from a mantle plume implicated in the rifting of the supercontinent Columbia at ~1500 Ma.
53

Johan Axel Björkman och P.A. Björkman : Två prostarkiv

Eriksson, Josefin January 2012 (has links)
This essay has its background in the work I’ve been conducting organizing and cataloging two personal archives concerning the life and work of two vicars, Johan Axel Björkman and P.A. Björkman. The time span of the papers stretches from 1823 to 1982. The main problems I’ve been confronted with during this work have to do with respecting provenance and original order. I discuss these principles in relation to the experiences I’ve had with the vicar archives as well as to the special character of personal archives in general. I also discuss the use of Martin Grass’ scheme for personal archives. The essay constitutes my one year master’s thesis in archival science.
54

Geochemical study of the Mesoproterozoic Belt-Purcell Supergroup, western North America : implications for provenance, weathering and diagenesis

Gonzalez-Alvarez, Ignacio Jose 04 January 2006 (has links)
Provenance in the lower Belt-Purcell Supergroup is constrained based on geochemical systematics and chemical monazite ages of argillites and sandstones. Rare earth element (REE), Cr-Ni, and Th/Sc-Sc systematics is equivalent for both facies and consistent with a dominantly post-Archean source area. Detrital monazite chemical ages restrict major provenance for the Appekunny and Grinnell sandstones and argillites to Paleoproterozoic terranes at ~1800-1600 Ma, minor contributions at ~1600-1500 Ma, and marginal contributions from Archean terranes at ~2600, likely in Laurentia. Similar detrital age spectra for monazites of argillites and sandstones of the Appekunny Formation are consistent with a common provenance for the two facies.</p> <p>The Belt-Purcell sequence records three major diagenetic stages displayed in argillites and sandstones: (1) K-addition and rare earth element post-Archean upper continental crust (PA-UCC)-like pattern; (2) a stage characterized by heavy REE enrichment relative to light REE and HFSE fractionation, and U and Ce mobility; and (3) local dolomitization with REE and high field strenght elements (HFSE) mobility. REE and HFSE mobility are interpreted as the result of oxidized alkaline brines developed by dissolution of evaporites. Monazites from the Appekunny and Grinnell formations differ compositionally and texturally in two groups. Rounded or inclusions with ages >~1400 Ma, interpreted as detrital, have higher Th2O, Y2O3 and lower LREE/HREE contents than euhedral individual monazite grains with chemical ages <~1400 Ma that posses opposed compositional characteristics, and viewed as diagenetic. Monazites that span <~1400 to 300 Ma could be the result of basinal brine activity during stages (2) and (3). </p> <p>Chemical index of alteration (CIA) for argillites and sandstones, corrected for a diagenetic K-addition average 73 and 66 respectively. These results, coupled with correlation of CIA with Eu/Eu*, low K/Cs ratios, and low Sr, Ca, and Na relative to PA-UCC, could be interpreted as the result of an moderate weathered provenance in a hot, wet climate being drained by a large-scale river system. Presence of minor pristine feldspars lowers the CIA values, and may signify minor contributions from proximal source with short-river transport under the arid to semi-arid climate in the depositional setting. Moderate to intense weathering of the larger provenance may be associated with elevated levels of atmospheric CO2 degassed from a mantle plume implicated in the rifting of the supercontinent Columbia at ~1500 Ma.
55

A culture of convenience? obsidian source selection in Yellowstone National Park

Park, Robin J. 30 March 2010 (has links)
Obsidian was a prized tool stone heavily exploited in the Greater Yellowstone Ecosystem throughout the pre-contact period. Fifteen geochemically distinct sources in this area were utilized on a regular basis consistently through time. A large dataset of sourced obsidian artifacts currently exists but has rarely been applied to specific archaeological problems for Yellowstone National Park, Wyoming.<p> This thesis provides a comprehensive list of obsidian sources important to the archaeology of Yellowstone and analyzes spatial and temporal trends of obsidian source selection. This study examines diagnostic tools produced by people during the Archaic period, focusing on the McKean complex (~5500-3000 BP) and Pelican Lake phase (3000-1600 BP). The potential for a cultural preference for obsidian source selection is discussed by applying landscape theory and ethnographic evidence to the examination of archaeological data.<p> A pattern of obsidian source exploitation as seen at the Osprey Beach site (representing the Cody Complex) has led to the development of a proposed annual round, typically applied to the entire pre-contact period in the Park. This large annual round, however, is determined to be unlikely and unnecessary by this author. Alternative local rounds to this model are proposed and supported by the evidence.<p> A clear preference for the Obsidian Cliff source (a National Historic Landmark) located in the northern end of the Park is shown in these results. This preference can be interpreted in both economic and cultural terms. Otherwise, no purely cultural preference for an obsidian source is supported. The exploitation of certain obsidian sources did not change significantly between the McKean and Pelican Lake cultures. However, a significantly different pattern of exploitation is seen when analyzed by geographical area. The results of this research suggest a more localized pattern of obsidian exploitation than previously thought, impacting interpretations of seasonality and travel routes in the Yellowstone area.
56

Foreland basin evolution and exhumation along the deformation front of the Eastern Cordillera, northern Andes, Colombia

Bande, Alejandro Ezequiel 23 December 2010 (has links)
Tracking the phases of Cenozoic deformation in the Eastern Cordillera of Colombia has proven to be a challenging task. Clear disagreements remain in interpretations of the timing of uplift of the Eastern Cordillera, possibly based on difficulties in distinguishing first-cycle Central Cordillera grains from recycled Eastern Cordillera clasts. This thesis focuses on the Eocene-Pliocene sedimentary record of the eastern foothills of the Eastern Cordillera at a latitude of 6°N, integrating basin analysis with several provenance techniques in order to date the activation of several thrust systems. Based on assessments of depositional environments and sediment dispersal patterns together with mineralogical and geochronological provenance, the onset of uplift in the axial zone of the Eastern Cordillera is constrained to be Oligocene. Prior to uplift, deposition in the eastern foothills was sourced from the eastern craton. Following the Oligocene episode, a continuous eastward advance of deformation is documented. An early Miocene episode probably reactivated the easternmost Cretaceous rift boundary along the eastern side of the Eastern Cordillera. Subsequent footwall shortcuts of those faults initiated activity in the middle to late Miocene, creating an intermontane (piggyback) basin in the eastern foothills at that time. In the preferred interpretation, this in-sequence history of thrust activation represents the main phases of deformation in the Eastern Cordillera from Eocene to Pliocene time, with neotectonic activity recording continued shortening. / text
57

Participatory archiving: exploring a collaborative approach to Aboriginal societal provenance

Rydz, Michelle 23 September 2010 (has links)
This thesis outlines the history of thinking about provenance in the archival profession, focusing specifically on the emergence of the concept of societal provenance and its implications for Aboriginal societal memory. It presents various ways in which the archival profession is currently involved in participatory projects for the public at large and for Aboriginal communities in particular. This thesis asks the question, if records are a creation of community and society, then should not community and society be more involved in their archiving? The thesis calls on archivists to advance the practice of participatory archiving by continuing to engage in collaborative projects, to open dialogue between the archival profession and Aboriginal communities as a means of establishing relationships of trust, and to embrace ways of remembering that challenge and unsettle the traditional archival application of provenance.
58

AGE OF THE WALDEN CREEK GROUP, WESTERN BLUE RIDGE PROVINCE: RESOLVING A DECADES-OLD CONTROVERSY VIA DETRITAL MINERAL GEOCHRONOLOGY AND SEDIMENTARY PROVENANCE ANALYSIS

Kelly, Evan A 01 January 2014 (has links)
Originally mapped as Precambrian and uppermost Ocoee Supergroup (OS), recent discoveries of Paleozoic microfossils have placed the Walden Creek Group (WCG), eastern Tennessee, into a younger depositional framework (Silurian or younger). In this study, monazite geochronology using SIMs, detrital zircon U-Pb geochronology determined by LA-ICP-MS, feldspar compositions determined by microprobe, zircon-tourmaline-rutile (ZTR) indices, and framework mineral modes were used to characterize provenance of sandstones of the WCG. Monazite ages cluster at 450 and 1050 Ma. All Ordovician ages are from grains that, in BSE images, have inclusion-rich microtextures interpreted as diagenetic and/or metamorphic, thus requiring that the WCG was deposited prior to Taconic metamorphism. The WCG heavy mineral suite is similar to the OS in its low modal abundance of monazite, but contains a slightly higher ZTR index. WCG Feldspar compositions are sodium poor-Kfs and sodic plagioclase, like the OS. Detrital zircon U-Pb ages for three formations of the WCG (seven samples total, n = 620) match the Ocoee signature. The dominant age modes are at ca. 1000 and 1150 Ma, with smaller modes at 1450 and 650 Ma. The monazite ages and supporting observations prove the WCG is not Paleozoic and its source rock signature matches the underlying OS.
59

Cloud Services Brokerage for Mobile Ubiquitous Computing

2015 June 1900 (has links)
Recently, companies are adopting Mobile Cloud Computing (MCC) to efficiently deliver enterprise services to users (or consumers) on their personalized devices. MCC is the facilitation of mobile devices (e.g., smartphones, tablets, notebooks, and smart watches) to access virtualized services such as software applications, servers, storage, and network services over the Internet. With the advancement and diversity of the mobile landscape, there has been a growing trend in consumer attitude where a single user owns multiple mobile devices. This paradigm of supporting a single user or consumer to access multiple services from n-devices is referred to as the Ubiquitous Cloud Computing (UCC) or the Personal Cloud Computing. In the UCC era, consumers expect to have application and data consistency across their multiple devices and in real time. However, this expectation can be hindered by the intermittent loss of connectivity in wireless networks, user mobility, and peak load demands. Hence, this dissertation presents an architectural framework called, Cloud Services Brokerage for Mobile Ubiquitous Cloud Computing (CSB-UCC), which ensures soft real-time and reliable services consumption on multiple devices of users. The CSB-UCC acts as an application middleware broker that connects the n-devices of users to the multi-cloud services. The designed system determines the multi-cloud services based on the user's subscriptions and the n-devices are determined through device registration on the broker. The preliminary evaluations of the designed system shows that the following are achieved: 1) high scalability through the adoption of a distributed architecture of the brokerage service, 2) providing soft real-time application synchronization for consistent user experience through an enhanced mobile-to-cloud proximity-based access technique, 3) reliable error recovery from system failure through transactional services re-assignment to active nodes, and 4) transparent audit trail through access-level and context-centric provenance.
60

Turquoise exchange and procurement in the Chacoan World

Hull, Sharon Kaye 18 September 2012 (has links)
The large amount of turquoise artifacts recovered from archaeological sites in the American Southwest and Mesoamerica suggests that turquoise was an important commodity in pre-Columbian trade networks. However, the spatial and temporal patterns of turquoise exchange networks and the provenance regions of the turquoise in the southwestern United States and Mesoamerica are poorly understood. Turquoise (CuAl6(PO4)4(OH)8•4(H2O)) is a supergene mineral that forms from meteoric water along fractures that are often associated with copper porphyry deposits. This copper-rich mineral can range in color and chemistry within a single sample or deposit. The ability to identify the turquoise resource areas of turquoise artifacts using the stable isotopes of hydrogen (2H/1H) and copper (65Cu/63Cu) has overcome many of the limitations of trace element analyses of complex minerals such as turquoise. The geography and geology of turquoise deposits dictate the isotopic composition of turquoise. Employing the Secondary Ion Mass Spectrometry (SIMS) technique to measure the hydrogen and copper stable isotope ratios in turquoise samples, a comparative reference database consisting of 876 analyses from 21 turquoise resource areas in the western United States was established. Sixty-two turquoise artifacts recovered from Aztec Ruin, Salmon Ruin, and nine sites in Chaco Canyon were analyzed and their isotopic signatures were compared to the reference database identifying the turquoise resource areas of 35 artifacts. These results were compared to pre-existing models of trade and exchange in the American Southwest and models that explain the complex culture history of the inhabitants of these sites. The results showed that turquoise was obtained from several different turquoise provenance regions across the western United States and there are notable differences in the turquoise procurement patterns between the three major great houses and between Pueblo Bonito and the small sites within Chaco Canyon. The results from this study improved the understanding of turquoise trade and relationships among the occupants of important Ancestral Puebloan sites in northwestern New Mexico. The development of the turquoise comparative reference database established the foundation of future research for reconstruction of ancient turquoise trade networks and investigation of turquoise procurement strategies in the American Southwest and Mesoamerica.

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