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The seasonality, diversity and ecology of cavernicolous guano dependent arthropod ecosystems in southern AustraliaMoulds, Timothy A. January 2006 (has links)
Includes copies of author's previously published works / Guano deposits in caves form a rich food resource supporting diverse arthropod communities. Guano piles consist of distinct micro - habitats, fresh, moist, highly basic guano and older, dry, slightly acidic guano. Micro - habitat variation is strongly controlled by seasonal guano deposition that, in turn, effects the structure of arthropod communities. The maternity chamber of Bat Cave, Naracoorte, South Australia, contains extensive guano deposits supporting 38 species from three classes and 12 orders. This community was studied to determine spatial and temporal variation of arthropod communities, and biogeographic relationships between different regions in Australia. Species richness forms a positive linear relationship with pH, in situ moisture content and guano deposition. Many species show strong associations with fresh guano and hence are strongly seasonal, although some species are present throughout the year. Arthropod community structure in winter was found to be more closely related to prior summer arthropod structure than to subsequent seasons. Starlight Cave near Warrnambool, western Victoria, the only other maternity site for Miniopterus schreibersii bassanii, contained 43 species from 39 families and 14 orders. Seven species are common to both caves. The community structure of Starlight Cave was found to be more homogeneous than Bat Cave with samples clustering by season rather than sample year as was the case at Bat Cave. Different cave morphology was found to significantly alter the micro - habitat conditions and, hence, community structure in Starlight Cave compared with Bat Cave. Migration of guano associated arthropods at local, regional and continental scales was assessed using mtDNA and allozyme electrophoresis the pseudoscorpion genus Protochelifer as a model organism. Phylogenetic tree reconstruction revealed a wide geographic distribution of cavernicolous species across southern Australia. Cave colonisation is believed to have occurred only once, followed by dispersal to the Nullarbor Plain and other caves in south - eastern Australia. Dispersal was possibly phoretic on cave bats or occurred prior to aridification of surface environments that currently restricts migration. The distribution of guano - associated arthropods from arid, semi - arid and monsoonal karst areas in Australia are compared with temperate south - eastern Australia. Different climatic areas show large biogeographical differences in community structure, although similar families ( Urodinychidae, Reduviidae, Anobiidae, Carabidae and Tineidae ) are present in many Australian guano communities. Several potential mechanisms of dispersal are discussed including phoresy, colonisation from soil, terrestrial migration and interstitial cavities. Endemism to specific caves cannot be definitely assigned to any species, although 13 species show restricted distribution. / Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2006.
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I inneslutande VR : En kvalitativ undersökning om användares närvarokänsla första gången de befinner sig i en virtuell miljö.Gustafsson, Jenny, Phensadsaeng, Arachaya January 2006 (has links)
Syftet med denna uppsats är att göra en undersökning om vilka faktorer som påverkar användares närvarokänsla första gången de använder sig av en inneslutande virtuell miljö. De inneslutande VR tekniker vi har valt att fokusera på är Computer Automatic Virtual Environment (Cave) och Head Mounted Display (HMD). Forskaren Carrie Heeter beskriver tre typer av närvaro och forskarna Wallace Sadowski och Kay Stanney räknar upp faktorer som de påstår påverkar användarens närvarokänsla. Vår frågeställning är vilka likheter eller skillnader det finns mellan våra testpersoners svar och Sadowski och Stanneys faktorer. Vi intervjuade och genomförde ett test med tre testpersoner i en Computer Automatic Virtual Environment baserat på två program. Vi valde även att intervjua två experter om vilka faktorer de ansåg påverkade deras närvarokänsla första gången de använde sig av en HMD. Första programmet som testpersonerna fick pröva på var Cuevadefuego som bestod av tredimensionella bilder till skillnad från det andra programmet, Crayoland, som bestod av tvådimensionella bilder. Intervjufrågorna till testpersonerna och experterna baserades på frågor som handlade om experternas och testpersonernas reaktioner och intryck relaterat till deras närvarokänsla och vad de trodde det var som påverkade deras närvarokänsla. Resultatet av intervjuerna och testet är att det finns likheter mellan de faktorer som testpersonerna anser påverkar deras närvarokänsla och med Sadowski och Stanneys faktorer men inga direkta skillnader.
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Late Holocene Paleoenvironmental Reconstruction in BarbadosOuellette, Gilman Reno 01 August 2013 (has links)
Barbados is the easternmost island in the Caribbean region, and is uniquely situated between the Atlantic Ocean and Caribbean Sea. Being an isolated island with a karstified aquifer providing the majority of the nation’s water resources, Barbados has found itself in water scarce situations in recent years. In order to better understand natural shifts in groundwater recharge (which is determined by shifts in precipitation), longer records of precipitation are needed than are available from modern measurements. This study presents a paleoclimate reconstruction for the late Holocene on Barbados using stable and radiogenic isotope ratios in speleothem lamina as proxies. In addition, it introduces the use of novel mineralogical analyses using Raman spectroscopy and large chamber-scanning electron microscopy to supplement the oxygen isotope record. For the past 1,500 years, the speleothem record indicates average δ18O values near -4.1 0/00, maximum δ18O values around -3.2 0/00 that coincide with the Little Ice Age climate event, while minimum δ18O values around -5.3 0/00 occur during the Medieval Climate Anomaly. Raman spectral analysis shows a recent period of increased Mg substitution, which potentially represents anthropogenic changes to the island’s epikarst aquifer caused by European settlement and sugar cane cultivation on Barbados. Electron imaging revealed chemically distinct layers of detritus within the stalagmite sample, facilitating precise sampling for U-series dating while also providing some information on the nature of weathering on the island. Additionally, time series analysis of the isotope record indicates multidecadal and multicentennial periodicities that conform well to that of the Atlantic Multidecadal Oscillation exerting influence on rainfall variability at the decadal scale, and the Intertropical Convergance Zone modulating rainfall at the multicentennial scale. Collectively, these data provide a climate reconstruction for the island of Barbados that is useful for better understanding change in cyclic precipitation patterns, as well as non-destructive methods for speleothem analysis that complement the isotopic study, while allowing sample preservation.
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Den andra verkligheten : En teoretisk studie i jämförelsen mellan Virtual Reality och verklighet / The other reality : A theoretical study of ”virtual” vs. ”real” realityKlangeryd, Malin January 2010 (has links)
Frågan om verkligheten och dess beskaffenhet har länge orsakat stor förbryllning hos människan, vilken historiskt sett har försökt förklarats på olika sätt. Inte minst genom olika slags gudaläror. Idag lever vi helt annorlunda än vad vi gjorde för exempelvis 1000 år sedan. Det är inte längre gudar som är den dominerande verkligheten – det är IT-tekniken. Idag lever alltfler människor i virtuella världar, så kallade Virtual Realities, som en stor del i deras liv. Så vad är verkligheten? Kan en virtuell verklighet vara verklig? Med dessa frågor i bakgrunden, och genom att applicera ett vardagssociologiskt perspektiv på forskningsresultat inom Virtual Reality, prövar denna uppsats synen av vad som är verkligt eller inte. / Projekt Visualisering
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Immersive Representation of Building Information ModelNseir, Hussam 2011 May 1900 (has links)
Building Information Modeling (BIM) is an emerging technology that utilizes 3D graphical representations to improve communication, collaboration, and data exchange. Immersive Visualization Environment (IVE) is another promising technology that enhances the 3D graphical representation to achieve a higher level of a sense of presence. The connection between the BIM technology that utilizes the 3D graphical representation and the IVE technology that enhances the 3D graphical representation has led many professionals to visualize BIM in immersive environments. This study is an attempt to overcome a systematic issue presented by available immersive visualization systems. The problem is that in order to visualize an information-rich BIM model from a commercial BIM application in an immersive visualization environment, the BIM model needs to pass through a tough conversion process and loss a large amount of its information. This research study utilizes the Application Programming Interface (API) of a commercially available BIM application to develop an immersive visualization environment. This approach was applied on Autodesk Navisworks software by developing a software program that utilizes Navisworks' API to control Navisworks' camera angle and generate an immersive visualization environment. A prototype of the approach was built in the Department of Construction Science at Texas A & M University and named BIM CAVE Prototype.
The overall goal of this research was to prove that it is possible to transform a commercial BIM application into an immersive visualization system. A phenomenological study was utilized by interviewing subject matter experts from the construction industry. The intent of this effort was to explore and develop a phenomenological understanding of how research participants perceived the BIM CAVE system. The results show that the BIM CAVE can be considered an immersive visualization environment because it contains a majority of the immersive visualization environment features. However, a variety of technical limitations must be overcome before it can be called a fully immersive and functional visualization environment. Moreover, even though this investigation was to some extent successful, this research approach needs to be tested on other commercially available BIM applications before generalizations are made.
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An Investigation On The Mineralogical, Petrogaphical And Chemical Properties Of Stone Objects From KaraEfe, Mehmet 01 February 2012 (has links) (PDF)
The archaeological and technical questions about ancient stone
tools lead to various research activities such as chemical and
petrographical analysis.
Considering research areas and publications it can be suggested
that mineralogical studies of stone samples of ancient stone tools have
disclosed useful information concerning identification of the stone.
Within this context, aim of this study is to determine the chemical,
mineralogical and petrographical identities of the stone samples of Karain
Cave (Antalya).
Most paleolithic caves show one specific time interval layer but Karain Cave
shows lower-upper and middle layers which give information about the
migration ways between Near East and Europe.
Stone tools excavated from Karain Cave are not only first human
remainings in Anatolia but also first artworks of Anatolian people.Most of
the stone tools excavated from Karain Cave are cherts. These cherts
were analysed for archeological aspects but mineralogical, petrographical,
and chemical contents have not been analysed yet. During the
excavations at the Karain Cave in Antalya many stone pieces in
different sizes and colors had been found. In this study ten samples were
examined. The methods used consists of thin section, X- ray powder
diffraction , scanning - electron microscopy coupled with energy dispersive
X-ray analysis , differential thermal analyses and inductively coupled
plasma mass spectrometry to determine material characteristics of the
samples.
Petrographically the nine of the samples are chert with some including
radiolarian fossils. Microcrystalline á / - quartz is the major mineral in the
chert. Only one sample is composed calcite and is identified as micritic
limestone. Chemical analysis reflect the typical composition of chert with the
average values of / 40.9% Si and 1 sample is limestone, which is
composed of 35.7% Ca . Minor elements are Fe, Al, K, and Ti in the
samples. Thermal analysis is also supported the thin section studies.Further
research is suggested for provenance analysis of stone tools from the
Karain Cave.
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Prehistoric caches in an intermittent wetlands environment : an analysis of the Nicolarsen Cave collection, Washoe County, Nevada /Barnes, Robin Benson, January 2000 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 215-225). Available also in a digital version from Dissertation Abstracts.
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The Biogeochemistry of Submerged Coastal Karst Features in West Central FloridaGarman, Keith Michael 30 September 2010 (has links)
West Central Florida is a complex karst environment with numerous sinkholes, springs, and submerged cave systems. Many of these karst features are anchialine, located within the subterranean estuary where freshwater and saltwater mix. Water quality data and/or fauna data were obtained from twenty-one karst features and their associated cave systems. The anchialine karst environment of the study area has a wide range of habitats with measured salinities ranging from freshwater at <0.2 ppt to sulfidic, hypersaline water at 38.5 ppt and measured pH readings ranging from 6.39 in water impacted by sulfur oxidizing bacteria to 10.3 in an isolated room of a cave. Stygobitic crustaceans were identified in conduits extending beneath the Gulf of Mexico supporting the hypotheses that freshwater crustaceans could survive higher sea levels in freshwater conduits beneath saltwater. The fauna associated with the anchialine cave systems included Sabellidae and Polychaeta worms, hydroids, cnidarians and hydrobiid snails. Jewfish Sink, like other anaerobic marine basins that were submarine springs, has four zones: oxic zone, transition zone, upper anoxic zone and anoxic bottom water. The upper zones have seasonal water quality variations from winter cooling and sinking of surface water and changes in the microbial communities. Activity of sulfate reducing bacteria is carbon limited in the anoxic zones, where sulfate reduction is the major metabolic process, and primary production is phosphate limited in the oxic zones. Organic input from the Gulf of Mexico drives the bacterial anaerobic ecosystem, resulting in a “sulfide pump”, in which sulfide percolates upward removing oxygen from the overlying sediment.
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Alternative approaches to the identification and reconstruction of paleoecology of Quaternary mammalsGeorge, Christian Owens 25 February 2013 (has links)
Since the 19th century the remains of Quaternary mammals were an important source of data for reconstructing past environmental conditions. I tested two basic assumptions that underlie Quaternary vertebrate paleoecology. The first assumption is that fossils mammals can be identified reliably to species. The second assumption is that correlations established between extant mammals and environmental parameters can be used to interpret reliably the paleoenvironment from the latest Pleistocene.
Incorrect specimen identifications could lead to errors in paleoecologic interpretations. I explicitly tested an alternative to the traditional approach to identification by identifying fossil shrews based on apomorphies. My results indicated that some traditional characters are useful for identification, but only complete specimens with a combination of characters can be identified to species. This indicates that previous authors who identified shrews to species did not compare them to the full diversity of species.
I tested the reliability of cenograms and species-richness models as approaches for the reconstruction of environmental conditions in the past. I used faunal data from Hall’s Cave, Kerr County, Texas to construct cenograms and species-richness models and compared the results to independent paleoclimate proxies. Neither species-richness models nor cenograms agree with paleoenvironmental reconstructions based on proxy data from the Late Pleistocene and Holocene. Cenograms and species-richness models are unreliable and fraught with problems, and both approaches should be abandoned as tools for paleoecological reconstruction.
To test for potential geographic bias in the identification of Quaternary fossils I developed a GIS (geographic information systems) database of Quaternary paleontological sites within Texas. I was able to show that the identification of species of fossil soricids, heteromyids, Odocoileus, and Spilogale was influenced by geography. Those fossils should be treated as generic identifications until they are re-evaluated against the full diversity of species. Utilizing GIS I also developed a method of paleoecological analysis. My analysis showed that the environmental conditions found today in Texas might not be limiting the current range of shrews. Based on the known geographic range of shrew fossils, other ecological factors besides environmental conditions are shaping the current distribution of shrews. / text
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Digital Dunhuang: the use of new technology for off-site interpretation of a fragile heritage siteChan, Fung-lin., 陳鳳蓮. January 2012 (has links)
The group cave-temples in Dunguang, Gansu Province of north-western China offer an unparalleled display of grotto art of over a thousand years from the fourth century to the fourteenth century. They represent a microcosm of ancient and medieval civilizations, providing us with enormous opportunities of heritage experience and understanding. However, these grotto treasures are extremely fragile. Over the centuries they have been suffering from serious deterioration and damage due to human and natural causes, and in recent decades the ever-increasing visitor load has posed even greater threat to the murals. The emerging trend of using advanced technology in the preservation and the interpretation of the grotto art offers new possibilities of remote access and interpretation which shall enhance understanding and enjoyment of the cultural treasures. This dissertation sets out to examine such trend of digital interpretation of heritage in off-site scenarios. The research includes a background of the study, the significance of the Dunhuang Caves, the application of new technology, followed by a case study of re-presenting and interpreting one of the Dunhuang caves in Hong Kong. / published_or_final_version / Conservation / Master / Master of Science in Conservation
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