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Reliability and clinical utility of the hand and wrist strength gaugeBroniecki, Monica January 2003 (has links)
TThis thesis looks at the development of a Hand and Wrist Strength Gauge. The gauge was developed by the author at the Flinders Medical Centre Occupational Therapy Department in 1997. / thesis (MApSc(OccupationalTherapy))--University of South Australia, 2003.
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Invertebrate diversity and vegetation heterogeneity : plant-invertebrate relationships in indigenous New Zealand grasslandsRate, Stephen R., n/a January 2005 (has links)
Spatial heterogeneity of the environment, as measured by floral diversity, composition and structure, is known to influence the distribution and diversity of invertebrates. Heterogeneity brought about by anthropogenic disturbance may be a threat to invertebrate diversity. This thesis investigates the impacts of vegetation heterogeneity at a range of scales on the diversity of invertebrate populations in modified high-altitude indigenous grasslands on the Rock and Pillar Range, Central Otago.
Invertebrates were sampled in and on the edges of snow tussock fragments to assess whether species richness increased systematically with fragment area. Invertebrate composition was poorly related to fragment area, plant composition and environmental variables. Taxon richness, abundance and/or diversity for three invertebrate groups increased as fragment area decreased, perhaps reflecting an influx of species from the surrounding matrix. For snow tussock leaf invertebrates in autumn, richness and abundance were at least two times lower in tussocks exposed to the wind than those in the centre of fragments, suggesting selection of habitat may be based on microclimatic characteristics.
Invertebrates were sampled from the bases of tussocks after they were clipped to simulate three levels of vertebrate grazing. Invertebrate community composition differed between sites and sampling dates but was unaffected by clipping treatment. At the higher altitude site invertebrate abundance was 1.45 times greater and Shannon-Wiener diversity (H�) 1.22 times lower than at the lower altitude site. The latter sampling date had higher abundance (2.12 times) and taxon richness (1.14 times) than the earlier date.
Pitfall-trapped invertebrates in cushionfield, herbfield and snow tussock differed in community composition and often by taxon richness, abundance and diversity. Across habitats, plant composition, plant diversity and some environmental variables were correlated with invertebrate variables, but could not be separated from vegetation type.
The invertebrates collected in the course of the study are listed. Four Phyla, eight Classes, 24 orders and over 300 taxa were recorded. Almost all taxa are endemic and many have limited distributions and/or are undescribed. A species list is provided with collection altitude, method and habitat type.
Invertebrate assemblages from sites differing in altitude, vegetation type and level of habitat modification on the Rock and Pillar Range are compared. Sites differed in species composition and rank orders of abundance and richness. At lower elevations, invertebrate richness was at least 25% less, and standardised trap abundance at least 44% less, than that at the highest elevation. Richness and abundance of exotic invertebrates decreased with increasing altitude.
This thesis highlights several points concerning the study of grassland invertebrates and heterogeneity on the Rock and Pillar Range. First, there are differences in invertebrate assemblages at a range of scales. Conserving invertebrate diversity will therefore require altitudinal sequences and different habitat types, including disturbed areas. At high elevations, tussock habitat may be disproportionately important due to its relative rarity. Second, the effects of disturbance on invertebrates were only visible at large spatial scales. Third, there is a paucity of research on New Zealand invertebrates, especially in regard to terrestrial disturbance, which has resulted in a shortfall of biological, distributional, taxonomic and ecological knowledge.
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Ecological change and piospheres : can the classical range succession model and its modifications explain changes in vegetation and soil around boreholes in eastern Botswana?Moleele, Nkobi Mpho, n/a January 1994 (has links)
There is concern that the communal rangelands of Botswana are overstocked with
cattle, and that this has led to unwanted ecological changes. These changes are
assumed to be most prominent around boreholes. This study describes vegetation and
soil piospheres around boreholes in Eastern Botswana and investigates factors
associated with their development.
The classical range succession model and its modifications, the bush encroachment
theories and the soil-nutrient transfer model, have been applied here to explain
changes in vegetation and soil variables with distance from artificial water points.
Data on soil texture, soil nutrients, vegetation species composition and cover, dung
weight and bare ground were collected from boreholes of different ages, with different
numbers of cattle using them.
Piosphere patterns were observed. However, some of the patterns were not in
accordance with the classical range succession model and the bush encroachment theories. The frequent occurrence of palatable grasses (Panicum maximum, Setaria
verticiliata and Digitaria milanjiand) nearer to water points where the grazing
pressure is highest, and of unpalatable ones (Aristida congesta and Eragrostis
rigidior) further away, where the grazing pressure is minimal, contradicts the classical
range succession model. Total tree cover along the gradient did not show any changes,
which contradicts bush encroachment theory (two-layer soil moisture model). The
concentration of soil nutrients and dung weight close to boreholes was well predicted
by the soil-nutrient transfer model. The frequency of Acacia tortilis and Dicrostachys
cinerea and bare patches, increased towards boreholes. Grass cover, occurrence of
Terminalia sericea, Boscia albitrunca and Combretum apiculatum increased with
distance from water points.
The results suggest that the range succession model and its modification, the twolayer
soil moisture model, cannot satisfactorily explain vegetation changes with
distance from water points. Species composition at a point may be affected by the
growth, survival, recovery and reproductive strategies of different species, fire,
selectivity of browsers and nutrients status, as well as grazing disturbance. Therefore,
the 'state and transition' model is recommended, as it considers factors that are ignored
by the classical range succession model, and is appropriate for analysing vegetation
change under highly variable rainfall.
The adverse impacts of grazing around boreholes could be reduced by controlling
cattle distribution on the range as a whole.
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網路上觀察立體影像之研究 / A Study on Stereoscopic Viewing on Internet蕭巧如, Hsiao, Chiao Ju Unknown Date (has links)
本研究的動機在整合攝影測量與網際網路技術,主旨為研究經由網路瀏覽立體影像之分析。為製作地物之立體影像,研究中使用非量度性數位相機,於地面垂直拍攝二棟建物,以補色原理製成數值像對,接著建置研究區之導覽網站,並將立體影像連結上網,提供立體觀察。本研究亦以Java程式設計立體浮測標,提供觀察者瞭解地物之遠近或高低。
實驗呈現若以柯達DC280數位相機進行近景攝影測量,前方交會地物檢核點之空間位置可達像空間上次像元之精度,像比例尺為1/1680時,相對精度可達物距之1/8400。研究結果顯示:結合攝影測量與網際網路可充分展現影像之三維空間。 / The ideal of this study is to put together the knowledge of Photogrammetry and web technology and then provide the 3D pictures for web browsers.
A non-metric digital camera is used in this research to shoot two building on the ground vertically. The color-contracting theory is applied to construct the website and create a stereoscopic viewing on the targets within the experimental range. In addition to color-contracting theory, floating mark designed with Java program is also used to help the web users better understand the distance and altitude in proportional to the surrounding objects.
According to the experiment in this research, pictures taken with Kodak digital camera model #DC280 together with help of close-range photogrammetry. turn out to beas accutate as those taken with sub-pixel standard (1:1680 proportion versus 1:8400 accuracy). Photogrammetry joins with Internet will successfully disclose the 3D concept and will promote the idea of Photogrammetry.
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Développement d'un système de scan automatique pour la détection des particules chargées dans OPERA et séparation des pions/muons de basse énergieRoyole-Degieux, P. 12 July 2005 (has links) (PDF)
L'expérience OPERA (Oscillation Project with Emulsion t-Racking Apparatus) se propose de vérifier les résultats de Super-Kamiokande, tout en détectant l'apparition de neutrino tau dans un faisceau originellement "pur" en neutrino muonique, révélée par la topologie caractéristique de la désintégration du tau. La cible d'OPERA est constituée de murs de briques qui sont une alternance de feuilles de plomb et d'émulsions. Les émulsions sont des trajectographes de grande précision (~1 micron) qui vont être utilisés en masse lors de l'expérience et leur analyse nécessite un système de scan automatisé dédié. Tout d'abord, cette thèse a consisté en la participation à la mise en place du premier laboratoire de scan en France. La précision obtenue est conforme aux exigences de l'expérience et la rapidité demandée sera atteinte dans quelques mois. Ensuite, la séparation des pions et des muons à basse énergie a étudiée. Les premiers résultats, montrant la possibilité d'une telle séparation, ont été exposés. Enfin, un programme de reconstruction de ces particules en fin de parcours a été développé et testé, tenant compte des performances de scan auparavant étudiées.
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Evaluation of Wireless Techniques for Short-Range Communication / Utvärdering av trådlösa tekniker för kommunikation över korta avståndSöderkvist, Jonas January 2003 (has links)
<p>On radar level gauges currently shipped by Saab Rosemount, some adjustments of the unit's parameters has to be performed in the field. Presently, this is a cumbersome procedure; the operator has to be very close to the gauge and he either has to carry with him a bulky configuration unit or use a basic control unit on the gauge. A wireless solution, where a portable device and a receiver replace the control unit, would both allow the operator to work from a distance and eliminate the need for the bulky device. </p><p>The most conspicuous restraint for such a solution is a very low allowed power dissipation. The reason for this is that some gauges do not have a separate power supply, but are fed directly off the communication bus. A viable solution should also be commercially available and robust enough to operate in an industrial environment. </p><p>To meet these requirements both a theoretical and a practical assessment was conducted, where the two techniques for wireless communication, IrDA, and Bluetooth, was given special consideration. As for the portable device, the market for hand-held computers was investigated and ultimately a PDA from Palm was selected for this project. Together with this PDA, a prototype for each of the two wireless techniques was tested to ascertain their performance with respect to power dissipation, communication range, and communication robustness. </p><p>This investigation revealed that Bluetooth could be used over a much greater distance than IrDA and it did also provide a more robust solution overall. IrDA is nonetheless also a competent technique, and has its primary advantage in terms of much lower power dissipation compared to Bluetooth.</p>
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Range Gated Viewing with Underwater CameraAndersson, Adam January 2005 (has links)
<p>The purpose of this master thesis, performed at FOI, was to evaluate a range gated underwater camera, for the application identification of bottom objects. The master thesis was supported by FMV within the framework of “arbetsorder Systemstöd minjakt (Jan Andersson, KC Vapen)”. The central part has been field trials, which have been performed in both turbid and clear water. Conclusions about the performance of the camera system have been done, based on resolution and contrast measurements during the field trials. Laboratory testing has also been done to measure system specific parameters, such as the effective gate profile and camera gate distances.</p><p>The field trials shows that images can be acquired at significantly longer distances with the tested gated camera, compared to a conventional video camera. The distance where the target can be detected is increased by a factor of 2. For images suitable for mine identification, the increase is about 1.3. However, studies of the performance of other range gated systems shows that the increase in range for mine identification can be about 1.6. Gated viewing has also been compared to other technical solutions for underwater imaging.</p>
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Image Based Visualization Methods for Meteorological DataOlsson, Björn January 2004 (has links)
<p>Visualization is the process of constructing methods, which are able to synthesize interesting and informative images from data sets, to simplify the process of interpreting the data. In this thesis a new approach to construct meteorological visualization methods using neural network technology is described. The methods are trained with examples instead of explicitely designing the appearance of the visualization.</p><p>This approach is exemplified using two applications. In the fist the problem to compute an image of the sky for dynamic weather, that is taking account of the current weather state, is addressed. It is a complicated problem to tie the appearance of the sky to a weather state. The method is trained with weather data sets and images of the sky to be able to synthesize a sky image for arbitrary weather conditions. The method has been trained with various kinds of weather and images data. The results show that this is a possible method to construct weather visaualizations, but more work remains in characterizing the weather state and further refinement is required before the full potential of the method can be explored. This approach would make it possible to synthesize sky images of dynamic weather using a fast and efficient empirical method.</p><p>In the second application the problem of computing synthetic satellite images form numerical forecast data sets is addressed. In this case a mode is trained with preclassified satellite images and forecast data sets to be able to synthesize a satellite image representing arbitrary conditions. The resulting method makes it possible to visualize data sets from numerical weather simulations using synthetic satellite images, but could also be the basis for algorithms based on a preliminary cloud classification.</p> / Report code: LiU-Tek-Lic-2004:66.
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Climate change impacts on mountain snowpack presented in a knowledge to action frameworkSproles, Eric Allan 16 February 2012 (has links)
Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges groundwater for over 1 billion people globally. Despite its importance to water resources, our understanding of the storage capacity of mountain snowpack is incomplete. This partial knowledge limits our abilities to assess the impact that projected climate conditions will have on mountain snowpack and water resources.
While understanding the effect of projected climate on mountain snowpack is a global question, it can be best understood at the basin scale. It is at this level that decision makers and water resource managers base their decisions and require a clarified understanding of basin's mountain snowpack. The McKenzie River Basin located in the central-western Cascades of Oregon exhibits characteristics typical of many mountain river systems globally and in the Pacific Northwestern United States. Here snowmelt provides critical water supply for hydropower, agriculture, ecosystems, recreation, and municipalities. While there is a surplus of water in winter, the summer months see flows reach a minimum and the same groups have to compete for a limited supply.
Throughout the Pacific Northwestern United States, current analyses and those of projected future climate change impacts show rising temperatures, diminished snowpacks, and declining summertime streamflow. The impacts of climate change on water resources presents new challenges and requires fresh approaches to understanding problems that are only beginning to be recognized. Climate change also presents challenges to decision makers who need new kinds of climate and water information, and will need the scientific research community to help provide improved means of knowledge transfer.
This dissertation quantified the basin-wide distribution of snowpack across multiple decades in present and in projected climate conditions, describing a 56% decrease in mountain snowpack with regional projected temperature increases. These results were used to develop a probabilistic understanding of snowpack in projected climates. This section described a significant shift in statistical relations of snowpack. One that would be statistically likely to accumulate every 3 out of 4 years would accumulate in 1 out of 20 years. Finally this research identifies methods to improved knowledge transfer from the research community to water resource professionals. Implementation of these recommendations would enable a more effective means of dissemination to stakeholders and policy makers.
While this research focused only on the McKenzie River Basin, it has regional applications. Processes affecting snowpack in the McKenzie River Basin are similar to those in many other maritime, forested Pacific Northwest watersheds. The framework of this research could also be applied to regions outside of the Pacific Northwestern United States to gain a similar level of understanding of climate impacts on mountain snowpack. / Graduation date: 2012
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Distribution of nearshore macroinvertebrates in lakes of the northern Cascade Mountains, Washington, USAHoffman, Robert L. 02 March 1994 (has links)
Although nearshore macroinvertebrates are integral members of high
mountain lentic systems, knowledge of ecological factors influencing their
distributions is limited. Factors affecting distributions of nearshore
macroinvertebrates were investigated, including microhabitat use and
vertebrate predation, in the oligotrophic lakes of North Cascades National
Park Service Complex, Washington, USA, and the conformity of distribution
with a lake classification system was assessed (Lomnicky, unpublished
manuscript; Liss et al. 1991).
Forty-one lakes were assigned to six classification categories based
on vegetation zone (forest, subalpine, alpine), elevation, and position
relative to the west or east side of the crest of the Cascade Range.
These classification variables represented fundamental characteristics of
the terrestrial environment that indirectly reflected geology and climate.
This geoclimatic perspective provided a broad, integrative framework for
expressing the physical environment of lakes.
Habitat conditions and macroinvertebrate distributions in study lakes
were studied from 1989 through 1991. Distributions varied according to
vegetation zone, elevation, and crest position, and reflected the
concordance between habitat conditions and organism life history
requirements. Habitat parameters affecting distributions included water
temperature, the kinds of substrates in benthic microhabitats, water
chemistry, and, to a limited extent, the presence of vertebrate predators.
The number of taxa per lake was positively correlated with maximum
temperature and negatively correlated with elevation. Forest zone lakes
tended to have the highest number of taxa and alpine lakes the lowest.
Substrates in nearshore microhabitats varied with vegetation zone.
Organic substrates were more predominant than inorganic substrates in
forest zone lakes. Organic substrates declined and inorganic substrates
increased in the subalpine zone. There were virtually no organic
substrates in alpine lakes. Taxa were placed into groups based on
substrate preference. Ordinations indicated that the proportion of taxa
in inorganic and organic-based substrate preference groups paralleled
vegetation zone-substrate relationships. Lake water hardness and pH, as
well as the presence of vertebrate predators affected the distribution of
several taxa. Gastropods were limited to three forest lakes by their
water hardness and pH requirements, and the dytiscid beetle, Potamonectes
qriseostriatus appeared to be absent from forest lakes due, in part, to
the pH requirements of this taxon. The distribution of three taxa
(Taenionema, Ameletus, Desmona) appeared to be affected by the presence of
vertebrate predators (salamanders and trout).
Discriminant analysis was used to test the reliability of lake
classification based on terrestrial characteristics. Discriminant
analysis assigned lakes to categories based on similarities in kinds of
substrates, substrate preference groups, and taxa. Strong concordance
between both methods of lake classification supported the interconnection
between terrestrial characteristics and processes and the abiotic and
biotic conditions in lakes. / Graduation date: 1994
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