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Dissertations / Theses on the topic 'Specks'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 February 2022

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1

Joswig, Klaus Dieter. "Der systemisch-ökologische Orientierungsansatz Otto Specks in der Heilpädagogik : zur Rezeption des systembiologischen Konstruktivismus und der soziologischen Systemtheorie in der speziellen Pädagogik /." Berlin ; Münster : Lit, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=2943498&prov=M&dok_var=1&dok_ext=htm.

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2

Bel, Patricia Damian. "Cotton quality - fibre to fabric: fibre properties relationships to fabric quality." University of Southern Queensland, Faculty of Engineering and Surveying, 2004. http://eprints.usq.edu.au/archive/00003193/.

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[Abstract]: The textile industry has a recurrent white speck nep problem in cotton. “White specks” are immature clusters of fibres that are not visible as defects until dyeing, after which they remain white on the surface of a darkly dyed fabric, or appear as non uniform streaks in the fabric. Both results render the fabric unsuitable for commercial fashion fabrics. The white speck potential of cotton is difficult to predict except in extremely immature cottons. Competitive synthetic fibres are uniform in length and strength and never have a maturity problem resulting in dye defects. They are much more predictable in the mill. As a result, cotton faces the risk of being replaced by synthetic fibres. Industry requires a method to predict fabric quality from cotton bale fibre properties to minimize this risk. This research addresses the problem of predicting white specks in dyed cotton fabrics. It is part of a large study, which is supported jointly by US and Australian agencies. The main objective is to predict fabric quality from bale fibre properties given controlled gin and mill processing. Gin and mill processing must be controlled so that field and varietal effects can be seen without the interaction of mechanical processing differences. This results in achieving other objectives, including the provision of baseline data for Australian varieties, ginning effects and comparison of ring and open-end spinning. Initially a reliable method for measuring white specks had to be found. Several systems have been evaluated and are reported here. The systems accuracy was compared using fabrics from the US Extreme Variety Study (EVS), which was grown specifically to have different levels of white specks. The fabrics made from the US (Leading Variety Study 1993 (LVS) and The American Textile Manufacturers Institute (ATMI) Cotton Variety Processing Trials, 2001) and the Australian (1998 & 1999) variety studies were analysed using AutoRate-2-03, the best of the image analysis systems studied. The final release of AutoRate (February 2003) was developed by Dr. Bugao Xu to measure white specks on dark fabrics in conjunction with this research. This final analysis of these studies results in white speck prediction equations from high-speed fibre measurement systems. This information should be immediately useful to as a tool to measure the effects of field and ginning practices on the levels of white specks without having to carry the research out to finished fabrics. Cotton breeders will be able to use the equations in the development of new varieties with low white speck potential, by eliminating varieties with high white speck potential early on. The research will continue on a much larger scale in the US and hopefully a WSP (White Speck Potential) value will be incorporated into the US Cotton Grading System.

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3

Ritchey, Brian Michael. "Quantitative Trait Loci Mapping Of Macrophage Atherogenic Phenotypes." Cleveland State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=csu1510080975338565.

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4

Kolotylo, Rebecca Ann. "Flight speeds and energetics of seven bird species." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/27499.

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Flight speeds of seven bird species, the Tree Swallow (Tachycineta bicolor), Mountain Bluebird (Sialia currucoides), White-throated Swift (Aeronautes saxatalis), European Starling (Siurnis vulgaris), Black Tern (Chlidonias nigra), Pigeon Guillemot (Ceppkus columba), and Red-necked Grebe (Podiceps grisegna), were recorded using a Doppler radar handgun. Velocities were measured of adult birds flying to and from foraging areas while rearing young, and totalled 1178 records. Morphological measurements were also made on some of the species and were used, along with literature values, to construct curves of estimated total power required for flight versus flight velocity for each species. The mean observed flight speed, V[sub obs], for each species was then compared to the minimum power speed, V[sub mp], and the maximum range speed, V[sub mr], on the power curve. For five of the seven study species, the V0be was significantly greater than V[sub mr], and thus appeared to be independent of morphology, foraging methods and habitats. The V0bs of the other two species was found to be between V[sub mp] and V[sub mr]for the Pigeon Guillemot and less than V[sub mp] for the Red-necked Grebe. In a more detailed study of the Tree Swallow and the Mountain Bluebird, V[sub obs] was determined to be fairly constant over the recording period. Individual power curves were constructed for five female Mountain Bluebirds and three female Tree Swallows, since both morphological measurements and flight speeds were recorded for these individuals. In each case, V[sub obs]was significantly greater than V[sub mr]. For the bluebird, it was also found that the number of visits to the nest per hour per nestling did not appear to increase with the age of the nestling. The rate of feedings, however, was quite variable for both the Tree Swallow and Mountain Bluebird. By setting the observed flight speed, V0be, equal to. a predicted optimal speed, V[sub obt], the net rate of energy gain during foraging by the parents could be determined. Comparing this energy gain with estimates of nestling energy requirements for both species resulted in the conclusion that the observed speed could not be the same as the optimal speed, and that in order to meet nestling requirements, the parents may increase their feeding rate during other parts of the day not under observation.
Science, Faculty of
Zoology, Department of
Graduate

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5

Persons, Annie. "Jasper Speaks." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5812.

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6

Cipriano, Margaret. "Tableau Where She Speaks." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1523442108801092.

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7

Newberry, Shawn. "Laser Speckle Patterns with Digital Image Correlation." OpenSIUC, 2021. https://opensiuc.lib.siu.edu/theses/2885.

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Digital Laser Speckle Image Correlation (DiLSIC) is a technique that utilizes a laser generated speckle pattern with Digital Image Correlation (DIC). This technology eliminates the need to apply an artifact speckle pattern to the surface of the material of interest, and produces a finer speckle pattern resulting in a more sensitive analysis. This investigation explores the parameters effecting laser speckle patterns for DIC and studies DiLSIC as a tool to measure surface strain and detect subsurface defects on pressure vessels. In this study a 632.8 nm 30 mW neon-helium laser generated the speckle pattern by passing through the objective end of an objective lens. All experiments took place in a lab setting on a high performance laminar flow stabilizer optical table.This investigation began with a deeper look at the camera settings that effect the effectiveness of using laser speckles with DIC. The first studies were concentrated on the aperture size (f-stop), shutter speed, and gain (ISO) of the camera. Through a series of zero-correlation studies, translation tests, and settings studies, it was discovered that, much like white light DIC, an increased gain allowed for more noise and less reliable measurements when using DiLSIC. It was shown that the aperture size and shutter speed will largely depend on the surface composition of the material, and that these factors should be investigated with each new sample of different surface finish.To determine the feasibility of using DiLSIC on pressure vessels two samples were acquired. The first was a standard ASTM filament wound composite pressure vessel (CPV) which had an upper load limit of 40 psi. The second was a plastic vessel that had internal subsurface defects added with the use of an air pencil grinder. Both vessels were put under a pressure load with the use of a modified air compressor that allowed for multiple loading cycles through the use of a pressure relief valve. The CPV was mapped out in 10-degree increments between the 90° and 180° markings that were on the pressure vessel, occurring in three areas, each one inch apart. The CPV had a pressure load applied to at 10, 20, 30,and 40 psi. DiLSIC was able to measure increasing displacement with increased loading on the surface of the CPV, however with a load limit of 40 psi no strains were detected. The plastic vessel had known subsurface defects, and these areas were the focus of the investigation. The plastic vessel was loaded with a pressure load at 5, 10, 12, 15, 17, and 20 psi. The 5 psi loaded image was used as a reference image for the correlation and decorrelation consistently occurred at 20 psi. This investigation proved that DiLSIC can detect and locate subsurface defects through strain measurement. The results were verified with traditional white light DIC, which also showed that the subsurface defects on pressure vessels were detectable. The DIC and DiLSIC results did not agree on maximum strain measurement, with the DiLSIC prediciting much larger strains than traditional DIC. This is due to the larger effect out-of-plane displacement has on DiLSIC. DiLSIC was able to detect subsurface defects on a pressure vessel. The median measured hoop strain was in agreement for DiLSIC, DIC and the predicted hoop strain for a wall thickness of 0.1 inches. However, DiLSIC also produced unreliable maximum strain measurements. This technique shows potential for future applications, but more investigations will be needed to implement it for industrial use. A full investigation into the parameters surrounding this technique, and the factors that contribute the most to added noise and unreliability should be conducted. This technology is being developed by multiple entities and shows promising results, and once further advanced could be a useful tool for rapid surface strain measurement and subsurface defect detection in nondestructive evaluation applications. Therefore, it is recommended to continue further investigations into this technology and its applications.

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8

Meng, Xiuzhe. "A STUDY OF SCRATCH FORMATION FROM RANDOM ORBIT SANDING OF WOOD SURFACES: INFLUENCES OF WOOD SPECIES, ROTATION SPEEDS AND GRIT SIZES." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1592487811911634.

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9

Islas, Melinda David 1945. ""The blood speaks"--Maya ritual sacrifice." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/291867.

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This paper examines ritual in Classic Maya art of the Usamacinta River drainage, focusing on blood sacrifice, its iconography and symbolism, then looks at contemporary Maya ritual in highland Chiapas, Mexico. Connections between the two are made, emphasizing the continuity of Maya culture in Mesoamerica, and suggestions are made for current archaeological investigations in the Maya area.

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10

Guimarães, Daniela Lapoli. "Words that sing, music that speaks." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/101929.

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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Letras/Inglês e Literatura Correspondente.
Made available in DSpace on 2013-07-15T23:34:41Z (GMT). No. of bitstreams: 0
O objetivo deste trabalho é analisar o uso de canções e efeitos sonoros em quatro produções teatrais de Romeu e Julieta, de William Shakespeare, enfocando os cruzamentos interculturais entre o texto e os vários contextos de performance. Este estudo propõe a análise do desenho sonoro como prática teatral, tomando como referência central teorias dos estudos musicais (Luiz Tatit e Marcos Napolitano), dos estudos de desenho sonoro (Deena Kaye, James Lebrecht e Livio Tragtenberg), da análise da performance (W. B. Worthen, Patrice Pavis, Susan Bennett, e outros), e de análises textuais, e levando em conta os estágios que envolvem uma produção teatral: concepção, produção, e recepção. O corpus da pesquisa é constituído pelas seguintes produções teatrais: Romeo and Juliet, da Royal Shakespeare Company, dirigida por Michael Bogdanov (1986); Romeo and Juliet, da Royal Shakespeare Company, dirigida por Michael Boyd (2000); Romeu e Julieta, do Grupo Macunaíma, dirigida por Antunes Filho (1984); e Romeu e Julieta, do Grupo Galpão, dirigida por Gabriel Villela (1992). O estudo demonstra que a análise da performance pode ser aprimorada ao enfocar a complexidade discursiva dos eventos sonoros, através da investigação dos momentos em que som e canção ocupam papéis importantes na cena teatral.

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11

Tingler, Stephanie Kay. "Oley Speaks and the Oley Speaks music library archive : a legacy of the twentieth century American art song /." The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1299527642.

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12

Vice, President Research Office of the. "Species Showdown." Office of the Vice President Research, The University of British Columbia, 2006. http://hdl.handle.net/2429/2700.

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13

Neamah, Zahra. "Molecular methods for species-specific identification of Bacillus species." Thesis, Bangor University, 2014. https://research.bangor.ac.uk/portal/en/theses/molecular-methods-for-species-specific-identification-of-bacillus-species(e7d73b70-8f43-48ac-822c-f0ecaadea110).html.

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14

Pulla, Siomonn. "From advocacy to ethnology, Frank Speck and the development of early anthropological projects in Canada, 1911-1920." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0017/MQ57681.pdf.

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15

Tsai, Lin-wai. "The laws for protecting endangered species in Hong Kong and Singapore /." View the Table of Contents & Abstract, 2006. http://sunzi.lib.hku.hk/hkuto/record/B37117348.

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16

Cheung, Tsz Wai Wallis. "In a Building, a Stairwell, a Room speaks." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5862.

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Working toward a personal definition of womanhood while progressing with my research in feminist discourse, I frame biographical events alongside the intricate use of language surrounding feminist theory. Experimenting with material specificities that speak to my personal narratives and cultural significance, my work seeks to address the interlacing operations of subjectivity expanding on the intersection of class, gender and race.

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17

Homan, Melicent L. "The Will Still Speaks When Nature Is Silent." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1085509509.

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18

Hecnar, Stephen J. "Species richness, species turnover, and spatial dynamics of amphibian communities." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0006/NQ30275.pdf.

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19

Andersson, Angelica. "Combined speckle interferometry and speckle correlation for non-destructive testing." Licentiate thesis, Luleå tekniska universitet, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17020.

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When a sample is studied during loading in a tensile test machine, the sample is often exposed to rigid body motions during loading at the same time as it deforms due to tension. Therefore, the small deformation field is hard, or impossible, to measure when it is overlaid by a large motion. The large rigid body motions can be measured with methods like speckle correlation (also called digital speckle photography, DSP), but the results might be of too poor accuracy to resolve the deformation field. Interferometric methods on the other hand might measure the deformation field but the rigid body motion makes the fringes disappear. In this thesis a method is presented that makes it possible to master such measuring situations, by a combination of speckle correlation and speckle interferometry (also called TV holography, ESPI or DSPI). Both theory and experiments are presented. It is shown that speckle correlation can determine the speckle motion in the recording in order to determine the small deformation field in the interferometric algorithm. Speckle correlation can also be used to determine the amount of shear in shearography allowing a quantitative determination of the spatial derivative of the deformation field.
Godkänd; 2000; 20070318 (ysko)

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20

Grantham, Stephen Gary. "Digital speckle radiography." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619648.

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21

Weissenegger, Karin. "Species that connect." Thesis, KTH, Arkitektur, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298830.

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People are growing older than they ever have before. My architectural proposal is a home for the elderly in a rural environment close to Stockholm.I think there is a large group of people, including me, who loves animals and recognizes their positive effect on wellbeing. I wanted to test the limits, how close the elderly and animals can live together in a functional and species-appropriate environment and to the benefit of both. Every individual on the site, Human or Non-Human, is providing care to some extent, the built environment supports these meetings and tasks in a subtle and natural way.

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22

Lourenço, Marisa Isabel da Costa. "Zoological species medicine." Master's thesis, Universidade de Évora, 2015. http://hdl.handle.net/10174/16445.

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Externship report done in order to describe and inform about the activities followed during six months externship at three zoological institutions in the United States of America. These externships were performed in order to conclude the sixth and last year of the integrated master in veterinary medicine of the University of Evora, with the main goal of obtaining more knowledge and experience in this area of the veterinary field. From the more varied number of species, to the more complex procedure, by exemplification with a case of preventative medicine in a western lowland gorilla (Gorilla gorilla gorilla), this report provides information about some of the most important and/or interesting aspects of zoological medicine; Resumo: Medicina das Especies Zoologicas Relatório de estágio produzido com o intuito de descrever e dar a conhecer as actividades seguidas e realizadas durante seis meses de estágio em três entidades zoológicas nos Estados Unidos da América. Estes estágios foram realizados de forma a concluir o sexto e último ano do ciclo de estudos do mestrado integrado em medicina veterinária da Universidade de Évora, com o objectivo principal de obter maior conhecimento e experiência nesta área do ramo veterinário. Desde o mais variado número de espécies, até ao procedimento mais complexo, atraves da exemplificacao com um caso de medicina preventiva num gorila-do-ocidente (Gorilla gorilla gorilla), este relatório fornece informação sobre alguns dos aspectos mais importantes e/ou interessantes da medicina zoológica.

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23

Hager, Heather Anne. "Conservation of species richness, are all umbrella species of similar quality?" Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ27503.pdf.

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24

Trachy, Suzanne 1962. "The Endangered Species Act: Political implications of delisting a recovered species." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/291698.

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The Endangered Species Act of 1973 (ESA) reflects society's concern over the rate of species extinction and aims to halt or reverse this trend. Several policies of the ESA protect listed species over resource development projects. Due to this protection, several listed species have recently experienced a recovery. Two have been removed, or delisted, from the federal Endangered Species list. Once a recovered species becomes delisted, the majority of these protections are removed. This paper analyzes the political implications of such delistings utilizing formal interviews, personal experiences, and a literature search. Through analysis, it is found that two specific policies seem to protect delisted species. It is concluded that a quantitative analysis may be premature at this time due to the small number of recovered species and that these policies must be effected to their fullest potential to ensure the long-term success of the federal endangered species program.

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25

Downer, Monica Ruth. "Plant Species Richness and Species Area Relationships in a Florida Sandhill." Scholar Commons, 2012. http://scholarcommons.usf.edu/etd/4030.

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Pine sandhill are integral pyrogenic communities in the southeastern United States. Though once widespread, habitat destruction, fire suppression and fragmentation have reduced the population to nearly 3%. It is important to learn as much as possible about these unique areas in order to implement best management practices to conserve and restore the existing populations of these communities. Fire is central to the maintenance of pine sandhill communities and two conceptual hypothesis regarding burn frequency have come to light in maintaining the unique species composition and richness of these areas. The first is the Intermediate Disturbance Hypothesis which suggests that intermediate fire regime maintains species diversity. The second is the Most Frequent Fire Hypothesis suggests that these areas should be burned as frequently as fuels allow. We used species area curves and species area relationships to answer the following questions about a pine sandhill community in the burn plot area of the University of South Florida Ecological Research Area (ERA). What are the patterns of species richness and how do they change with spatial scale? What are the factors contributing to the heterogeneity of this area and how much are they contributing? Do similarly burned areas have similar species composition? Do our results shed some light on the Intermediate Disturbance Hypothesis or Most Frequent Fire Hypothesis? We found that physical distance contributed more to species compositional and spatial patterns than burn regime or elevation, whose effects were small. On this particular scale, the results did not support either the Intermediate Disturbance Hypothesis or Most Frequent Fire Hypothesis, as acquisition rates of species in all burn regimes were quite similar. There was no obvious pattern of increased species richness with frequent or intermediate burning. Our results suggest a need for a dynamic plan for the conservation, preservation and management of pine sandhill communities. One must consider as many factors as possible when managing these lands, as every sandhill is unique. More research should be conducted on these ecologically sensitive and diminished areas in order to formulate best management practices to conserve, protect and restore pine sandhill in the southeastern United States.

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26

Zhang, Keda [Verfasser]. "Predicting skin permeability of neutral species and ionic species / Keda Zhang." Jena : Thüringer Universitäts- und Landesbibliothek Jena, 2013. http://d-nb.info/1033670235/34.

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27

Catano, Christopher. "Species and habitat interactions of the gopher tortoise: A keystone species?" Master's thesis, University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5153.

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Species-species and species-habitat interactions have been demonstrated to be important in influencing diversity across a variety of ecosystems. Despite generalities in the importance of these interactions, appropriate mechanisms to explain them are absent in many systems. In sandhill systems of the southeast U.S., gopher tortoises have been hypothesized to be a crucial species in the maintenance of diversity and function. However, the mechanisms and magnitude in which they influence their communities and habitats have rarely been empirically quantified. I examined how habitat structure influences tortoise abandonment of burrows and how tortoise densities influence non-volant vertebrate community diversity. Tortoise burrow abandonment is directly influenced by canopy closure, with each percent increase in canopy cover relating to a ~2% increase in the probability of burrow abandonment. In addition, tortoise burrow density was positively correlated with diversity and evenness, but not species richness. This influence was directly proportional to burrow density, supporting a dominance role for this species and rejecting the commonly asserted keystone species mechanism. I also quantified the influence of tortoises in influencing diversity relative to other environmental and habitat variables. Through this research, I have demonstrated that disturbance and habitat structure are important, but diversity responds most to density of burrows in the habitat. These findings demonstrate the intricate relationships interacting to maintaining diversity in sandhill systems. In particular, habitat change leading to declines of gopher tortoises may have drastic negative impacts on vertebrate species diversity.
M.S.
Masters
Biology
Sciences
Biology

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28

Celiker, Hasan. "Competition between species can drive public-goods cooperation within a species." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/70790.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 40-43).
Costly cooperative strategies are vulnerable to exploitation by cheats. Microbial studies have suggested that cooperation can be maintained in nature by mechanisms such as reciprocity, spatial structure and multi-level selection. So far, however, almost all laboratory experiments aimed at understanding cooperation have relied on studying a single species in isolation. In contrast, species in the wild live within complex communities where they interact with other species. Little effort has focused on understanding the effect of interspecies competition on the evolution of cooperation within a species. We test this relationship by using sucrose metabolism of budding yeast as a model cooperative system. We find that when co-cultured with a bacterial competitor, yeast populations become more cooperative compared to isolated populations. We show that this increase in cooperation within yeast is mainly driven by resource competition imposed by the bacterial competitor. A similar increase in cooperation is observed i
by Hasan Celiker.
S.M.

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29

Eningsjö, Frida. "The surrounding landscape’s impact on species density in species-rich grasslands." Thesis, Linköpings universitet, Biologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-143195.

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When the agricultural revolution took place, the biodiversity decreased and during the last century more than 90 % of the area of species-rich grasslands has been lost. Fragmentation has occurred with the area lost and insects, e.g. butterflies, suffer because of this. I investigated the impact that surrounding landscapes have on vegetation in species-rich grasslands, by using data from NILS and land use land cover data. I used the area of grassland, forest, water and arable land at radii from 100 m to 40000 m. All landscape structures showed a significant effect on the species density, but at different ranges. Arable and forest were both positive at large radii. Water had a negative effect at short ranges but positive at large ranges. The same was shown for grassland, and that is likely explained by grassland making up a very small proportion of the total area. In conclusion, species density in species-rich grasslands can partly be explained by the surrounding landscape. These results have implication for reserve selection, monitoring and restoration.

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30

Aboul-Khair, Shahira. "An Evaluation of Species Recovery under the U.S. Endangered Species Act." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31854.

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The U.S. Endangered Species Act (U.S. ESA) is one of the oldest pieces of legislation to protect endangered species. The bodies responsible for administering the U.S. ESA have published species Biennial Recovery Statuses (BRSs) in Reports to Congress on the Status of Endangered and Threatened Species. We found that expert assessments of species recovery trends match BRSs reasonably well; however, there appears to be a weak relationship between the BRSs and available data tracking species abundance and range trends. We aimed to establish whether the recovery trends of species examined were detectably associated with their threats, the general U.S. ESA tools, or recovery actions. We found positive associations between species recovery and two U.S. ESA tools – mean annual funding and peer-reviewed scientific information. However, correlations with other variables differ greatly depending on how recovery is defined. Species threats and recovery actions are also moderately related to their abundance and range trends.

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Dutrieux, Mariane. "Spatio-temporal species distribution modeling: Application to invasive alien species’ monitoring." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-224319.

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The developments of species distribution modeling techniques have brought new opportunities in the field of biological invasion management. In particular, statistical niche modeling for spatio-temporal predictions of species’ distribution is a widely spread tool that has proved its efficiency. The main purpose of this Master thesis is to study applicability of species distribution modeling to invasive alien species, with the aim of supporting efficient decision-making for their prevention. Some research questions are: how useful can species distribution modeling be for invasives’ prevention? Is distribution modeling technically feasible in the case of invasive species? What types of techniques are recommended to model distributions of IAS? What are the limits of such a tool? The methods employed to answer these questions are literature review and expert advice. I found that species distribution models can provide risk maps which are necessary to enable effective invasive alien species’ prevention. However intrinsic characteristics of invasives introduce uncertainties in the predictions made. Consequently several preliminary analyses should be conducted before applying the distribution model. Finally recommendations were made on the most appropriate distribution modeling technique to use depending on the urgency of the situation and the availability of data.
Utvecklingen av metoder för modelering av artdistribution har medfört nya möjligheter inom området hantering av biologiska invasioner. Statistisk nischmodelering för spatio-temporala förutsägelser av arters distribution är ett väl använt verktyg som har visat sig vara effektivt. Det övergripande målet med det här arbetet har varit att studera hur lämpad artmodelering är vid förebyggande av invasioner av främmande arter. Det har även undersökts huruvida metoden kan bidra till bättre och enklare beslutsfattande när det kommer till att förhindra sådana invasioner. Forskningsfrågorna lyder: hur användbart är fördelningsmodelering för förebyggande av spriding av invasiva arter? Är distributionsmodelering tekniskt genomförbar när det gäller invasiva arter? Vilka olika tekniker rekommenderas för att modelera spridningen av invasiva arter? Vilka begräsningar har modelerna? De metoder som används är litteraturöversikt och expertråd. Resultaten visar att artdistributionsmodelering kan bidra till att sammanställa riskkartor som är nödvändiga för att möjliggöra ett förebyggande arbete. Men speciella egenskaper hos de invasiva arterna som är svåra att förutse skapar osäkerheter i resultatet. Därför kan preliminära analyser med fördel genomföras innan modelering. I slutsatserna återfinns rekommendationer för vilken distributionsmodelteknik man bör använda, beroende av hur brådskande situationen är och om data finns tillgängligt.

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Marple, Norman C. "Worship that speaks to the core of our being." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/NQ65186.pdf.

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Yayan, Wahyu Candra Kusuma. "Ecological and genetic studies of endangered plant species, Vatica bantamensis and Rafflesia spp., for developing optimal conservation strategies in Indonesia." Kyoto University, 2019. http://hdl.handle.net/2433/244560.

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34

Jones, Leigh A. "Studies of littoral algae of the Isle of Wight and Solent region." Thesis, University of Portsmouth, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285928.

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Sundström, Alice Ulrika. "Tillväxt och blandskogseffekt i återplanterade objekt : Tecken på spatial inverkan på blandskogseffekt i unga trädbestånd." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-131056.

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2001 skedde ett kraftigt utbrott av Gremeniella abietina (Lagerb.) M. Morelet i området Bergvik, Dalarna. Skogsägarna var tvungna att avverka kraftigt i deras tallbestånd som respons på detta. I de objekt som återplanterades planterades det nya artsammansättningar än vad som planterats tidigare, gran och blandbestånd av gran och tall. I denna studie jämfördes och inventerades medelhöjderna på de återplanterade objektens träd för att skatta arternas framgång i de olika ståndorterna. Gran verkade vara mest lämpat eftersom den växte signifikant bättre än vad tillväxtekvationerna hade förutspått. Det påträffades även en positiv blandskogseffekt på trädens medelhöjd i provytorna. Provytor med högre antal arter, hade gran och tall med högre medelhöjd än artfattigare provytor. Provytor med tre arter, björk gran och tall hade högre tillväxt än provytor med endast tall och gran. Graden av inblandning i hela objektet hade inte någon signifikant effekt på medelhöjden. Detta tyder på att den spatiella artsammansättningen har större betydelse för de positiva effekterna av blandskog än artsammansättningen inom ståndorten i sin helhet. Detta antas vara på grund av nisch-komplementering och facilitering, möjligtvis via mykorrhiza interaktion. En annan möjlig förklaring är den minskade intra-specifika konkurrensen när individer av samma art är planterade med större avstånd sinsemellan. Troligtvis beror det på en nischuppdelning som tillåter de olika trädarterna att utnyttja markens tillgångar effektivare. Detta indikerar att småskalig artsammansättning är av vikt för tillväxten hos gran och tall.
In 2001 there was a serious outbreak of Gremmeniella abietina (Lagerb.) M. Morelet in the municipality of Bergvik in Dalarna, Sweden. The forest owners were forced to effectively cut their Pine stands in an attempt to halt the onslaught of the fungus. In the areas where new trees were planted after the cuttings, different compositions of species were implemented. Instead of only Pine (Pinus sylvestris), most of the new plantations consisted of spruce (Picea abies) or mixtures of the two species. In this study the average height of these replanted trees was measured to assess the success that the different species had in the different replanted areas. Spruce seemed to be the species that was best adapted to the local area because it grew significantly higher then what had been predicted. A positive effect of mixed-stands was also observed. The sample areas with three species, pine, spruce and birch (Betula pendula) had a higher average height then the sample areas that contained less species. The degree of mixture in the plantation as a whole had no significant effect on tree height. This implies that the spatial composition of species is of bigger importance then the quota of different species in the whole plantation. This could be explained by niche-complementation and by facilitation, probably via interactions between mykorrhiza. Intra-specific competition is another possible explanation for the greater height in sample areas with more species. Most likely because a decrease in intra-specific competition allows a division of niches and therefore permits the resources in the soil to be utilized more efficiently. The implication of this being that small-scale specie composition is of importance.

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Viljoen, Morné. "A critical review of the South African freshwater angling legislative framework / Morné Viljoen." Thesis, North-West University, 2010. http://hdl.handle.net/10394/4235.

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Prior to 1993, freshwater angling in South Africa had been governed by the respective nature conservation legislation of the four South African provinces, the four “independent homelands" and the six so-called Bantustans. In 1993 a South Africa with nine provinces was created, of which only Limpopo and Mpumalanga promulgated its own laws governing freshwater angling. From 2008 angling for listed threatened and protected freshwater fish species has been regulated by the National Environmental Management: Biodiversity Act, supplemented by the Threatened or Protected Species Regulations. In addition, it is anticipated that the Alien and Invasive Species Regulations, which will regulate angling for listed alien and invasive freshwater fish, will be promulgated in the near future. The result is that freshwater angling is currently being governed by a plethora of pre-1993 provincial, homeland and Bantustan legislation, two post-1993 provincial acts, as well as post-1993 national legislation. In this dissertation the South African freshwater angling legislative framework was critically analysed. It was found that the multitude of fragmented and complex laws, created 15 “angling provinces” which leads to confusion amongst anglers and government officials alike. In the process legal certainty and reasonableness, cornerstones of a sound legal system, are being compromised, indigenous freshwater fish are not adequately protected and alien or invasive freshwater fish are not properly managed. In the light of the above, and after taking comments by anglers and enforcement officials into account, recommendations are made for an improved legislative framework for freshwater in South Africa. It is recommended that all freshwater fish species be managed and/or protected on a catchment basis, as opposed to the current provincial basis. This will ensure legal certainty and reasonableness and that all indigenous freshwater fish which are subject to the similar threats are protected adequately and uniformly.
Thesis (M. Environmental Management)--North-West University, Potchefstroom Campus, 2010.

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Steinmann, Katharina. "Testing basic assumptions of species richness hypotheses using plant species distribution data /." Zürich, 2008. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000254735.

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Roland, Helen Elizabeth. "Science in environmental policy : defining species under the federal Endangered Species Act /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.

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Rasheed, Shaker M. "A reaction-diffusion model for inter-species competition and intra-species cooperation." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13545/.

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This thesis deals with a two component reaction-diffusion system (RDS) for competing and cooperating species. We have analyse in detail the stability and bifurcation structure of equilibrium solutions of this system, a natural extension of the Lotka-Volterra system. We find seven topologically different regions separated by bifurcation boundaries depending on the number and stability of equilibrium solutions, with four regions in which the solutions are similar to those in the Lotka-Volterra system. We study RDS in the small parameter of the range $0< \lambda \ll 1 $ (fast diffusion and slow reaction), and in a few cases we assume $\lambda=O(1)$. We consider three types of initial conditions, and we find three types of travelling wave solutions using numerical and asymptotic methods. However, neither numerical nor asymptotic methods were able to find a particular travelling wave solution which connects a coexistence state say, $(u_0,w_0)$ to an extinction state $(0,0)$ when $0< \lambda \ll 1 $. This type can be found when the reaction-diffusion system satisfy the symmetry property and $\lambda=1$.

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Kon, Kam King Guillaume. "Revisiting Species Sensitivity Distribution : modelling species variability for the protection of communities." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10194/document.

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La SSD (Species Sensitivity Distribution) est une méthode utilisée par les scientifiques et les régulateurs de tous les pays pour fixer la concentration sans danger de divers contaminants sources de stress pour l'environnement. Bien que fort répandue, cette approche souffre de diverses faiblesses sur le plan méthodologique, notamment parce qu'elle repose sur une utilisation partielle des données expérimentales. Cette thèse revisite la SSD actuelle en tentant de pallier ce défaut. Dans une première partie, nous présentons une méthodologie pour la prise en compte des données censurées dans la SSD et un outil web permettant d'appliquer cette méthode simplement. Dans une deuxième partie, nous proposons de modéliser l'ensemble de l'information présente dans les données expérimentales pour décrire la réponse d'une communauté exposée à un contaminant. A cet effet, nous développons une approche hiérarchique dans un paradigme bayésien. A partir d'un jeu de données décrivant l'effet de pesticides sur la croissance de diatomées, nous montrons l'intérêt de la méthode dans le cadre de l'appréciation des risques, de par sa prise en compte de la variabilité et de l'incertitude. Dans une troisième partie, nous proposons d'étendre cette approche hiérarchique pour la prise en compte de la dimension temporelle de la réponse. L'objectif de ce développement est d'affranchir autant que possible l'appréciation des risques de sa dépendance à la date de la dernière observation afin d'arriver à une description fine de son évolution et permettre une extrapolation. Cette approche est mise en œuvre à partir d'un modèle toxico-dynamique pour décrire des données d'effet de la salinité sur la survie d'espèces d'eau douce
Species Sensitivity Distribution (SSD) is a method used by scientists and regulators from all over the world to determine the safe concentration for various contaminants stressing the environment. Although ubiquitous, this approach suffers from numerous methodological flaws, notably because it is based on incomplete use of experimental data. This thesis revisits classical SSD, attempting to overcome this shortcoming. First, we present a methodology to include censored data in SSD with a web-tool to apply it easily. Second, we propose to model all the information present in the experimental data to describe the response of a community exposed to a contaminant. To this aim, we develop a hierarchical model within a Bayesian framework. On a dataset describing the effect of pesticides on diatom growth, we illustrate how this method, accounting for variability as well as uncertainty, provides benefits to risk assessment. Third, we extend this hierarchical approach to include the temporal dimension of the community response. The objective of that development is to remove the dependence of risk assessment on the date of the last experimental observation in order to build a precise description of its time evolution and to extrapolate to longer times. This approach is build on a toxico-dynamic model and illustrated on a dataset describing the salinity tolerance of freshwater species

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Giles, Mark. "Patterns of Species Rarity as a Driving Mechanism for Species Richness Gradients." Thesis, Université d'Ottawa / University of Ottawa, 2020. http://hdl.handle.net/10393/40587.

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Broad scale geographic variation in species diversity correlates with environmental variables in most taxa, but a mechanistic understanding of this relationship has remained elusive. More than a half-century ago, F.W. Preston observed that the number of individuals per species in species assemblages is log-normally distributed (with two parameters: the total number of individuals, I, and the number of individuals of the rarest species, m). Here, we show that ϕ, a proxy for m, is correlated with environmental variables in several datasets of trees, birds, fish, and invertebrates. Moreover, variation in species richness is more strongly related to this measure of rarity than to environment. In all the datasets we examined, structural equation models are consistent with the hypothesis that environmental variables affect species richness principally by affecting rarity, which in turn affects richness. We propose that geographic variation in the ability of species to persist at low densities provides a possible unifying explanation for global gradients of species richness. Our findings may have important implications regarding Earth’s biodiversity, highlighting the rarest species as those most at-risk but also important indicators for the ongoing consequences of climate change.

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42

Fourie, Arista. "Distinguishing between cryptic species in the Ceratocystis fimbriata sensu lato species complex." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/62102.

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Payer, Tilman. "Modelling extreme wind speeds." Diss., lmu, 2007. http://nbn-resolving.de/urn:nbn:de:bvb:19-67547.

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44

Lim, Kay Jin. "Varieties for Specht modules." Thesis, University of Aberdeen, 2009. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=53379.

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This thesis concerns the conjecture on the complexities of Specht modules made by VIGRE research group in Georgia. We show that the cohomological variety of a Specht module is the cohomological variety of a defect group of the block containing the Specht module if the defect group is abelian. In this case, the complexity of the Specht module is the p-weight of the corresponding partition. We also show that the latter statement holds if the partition is a hook partition or belongs to a large class of p-regular partitions. We give formulae for the generic Jordan types of signed permutation modules re- stricted to elementary abelian p-subgroups generated by disjoint p-cycles. This al- lows us to formulate the generic Jordan type of the Specht module corresponding to a hook partition restricted to elementary abelian p-subgroups generated by m disjoint p-cycles where m is the p-weight of the the hook. In the case where the partition is (pp), we show that the complexity of the Specht module is p-1 and we investigate the rank variety of the restricted module S(pp)↓E where E is a maximal elementary abelian p-subgroup of Sp² of rank p. In particular, we show that the degree of the projectivized rank variety is non-zero and divisible by (p-1)².

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Nagy, Gabor. "Diterpenoids from Salvia species." Thesis, University of Portsmouth, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264455.

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Staikidou, Ioanna. "Micropropagation of Galanthus species." Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437592.

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Taylor, Duncan Hugh. "Chemotherapy of Echinococcus species." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252947.

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48

Caldwell, Paul Edward. "Characteristics of Sulfobacillus species." Thesis, University of Warwick, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441691.

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Huang, Jen-Rong. "Optoelectronic speckle shearing interferometry." Thesis, Cranfield University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309680.

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Atcha, Hashim. "Optoelectronic speckle pattern interferometry." Thesis, Cranfield University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282405.

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