Dissertations / Theses: 'Disturbances'

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Kidd, Kathryn Rebecca Booker. "Forest Disturbances: Occurrences and Impacts of Recreational, Hydrogeomorphic, and Climatic Disturbances." Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/51765.

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Disturbances impact abiotic and biotic components within forested ecosystems. This dissertation identifies the impacts of recreational crossing disturbances on water quality, uses dendrochronological techniques to estimate sediment deposition and identify impacts hydrology and climate on radial growth in riparian forested wetlands, and quantifies influences of biotic and abiotic factors on the occurrence of frost-induced cambial damage. In southwestern Virginia, modeled soil erosion rates for multiple-use (hiking, mountain biking, and horseback riding) recreational trail approaches to stream crossings were found to be 13 times greater than rates for undisturbed forests. Downstream changes in macroinvertebrate-based indices indicated water quality was negatively affected downstream from culvert and ford crossings. These findings illustrate recreational stream crossings have the potential to deliver sediment into adjacent streams, particularly where best management practices are not being rigorously implemented, and as a result can negatively impact water quality below stream crossings. Impacts of hydrologic regime were apparent on sediment deposition and on green ash (Fraxinus pennsylvanica Marsh.) and water tupelo (Nyssa aquatica L.) radial growth along the Tensaw River in southwest Alabama. Annual dendrogeomorphic sediment accretion rates were significantly greater for a recent time period (25 years) when compared to longer term rates (131 years) along a natural levee and backswamp. Radial growth in green ash along the natural levee and backswamp was found to be significantly correlated with days flooded and average daily stage level during April while water tupelo further in the backswamp appeared resistant to hydrologic and climatic fluctuations. Results illustrate the importance of riparian wetlands in trapping sediment from adjacent waterways and highlight the role hydrologic regime plays in bottomland succession and productivity. Across northern lower Michigan, late spring frost-induced cambial damage in jack pine (Pinus banksiana Lamb.) occurred more frequently in younger trees and in trees with smaller diameters. Biotic and abiotic factors were found to influence the occurrence of earlywood frost rings. Frequent occurrences of frost-rings can be used to identify frost-prone environments and geographical boundaries for plant species. This dissertation bridged gaps in knowledge of recreational, hydrogeomorphic, and climatic disturbances in forested ecosystems which can be used to develop management strategies.
Ph. D.

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Glas, Michael, and Henrik Fredriksson. "Operational Disturbances in Supply Management : Sources and Managerial Approaches." Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Centre of Logistics and Supply Chain Management, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-18146.

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Nowadays global companies view the world as a single entity, sourcing materials fromanywhere and performing operations to create the optimal supply chain for their products.This leads to an increasing complexity which is driving supply management to becomea core capability of businesses. As supply chains are inherently vulnerable to disturbances,supply management will have to play a key role in the field of risk analysisand risk management. An increased awareness of sources of disturbances is essential tocreate significant improvements in the handling and prevention of disturbances.The purpose of this thesis is to identify and classify sources of disturbance which canhave a negative influence on a company’s supply management. This is achieved by theinvestigation of theories available in literature, as well as identifying and analyzing thedisturbances in the supply management of an international manufacturing company.Additionally, the theories on disturbance management are reviewed to create a foundationfor managerial implications.The company studied is Husqvarna, which currently is in a situation with several disturbancesin its supply management. The performed case study aims at both, describingthese phenomena, as well as testing of the theories. The chosen qualitative approachmakes it possible to gain in-depth knowledge and investigate different aspects ofsources of disturbances in this case study. The interviews performed are standardizedopen ended questionnaires in order to get in-depth knowledge of the situation.The empirical findings are then analyzed in regard to the purpose of the thesis. The goalof this analysis is to compare the sources of disturbances of the classification schemecreated in the literature review to the respondents’ answers from the interviews. Moreover,inputs and opinions from the respondents on how to manage disturbances are connectedwith the theories provided in the literature review within this field.Various sources of disturbance with a negative influence on the supply management ofcompanies are identified. It was also possible to compare the classification schemewhich was created based on the theoretical findings with the finding of the case study ofHusqvarna. Consequently a holistic overview of potential and actual sources of disturbancein supply management has been created. Furthermore, it is possible to contribute tothe body of knowledge on how to manage disturbances in supply management. Theprovided insights highlight implications that can help companies to successfully managedisturbances and hence improve their performance.

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Gedda, Petrus. "Disturbances in production." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-69299.

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Yazdani, Saami Kaveh. "Geometry induced flow disturbances." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/10023.

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From clinical studies it is well known that atherosclerosis has preferred locations in the vascular system, primarily sited in the carotid arteries, coronary arteries, and in vessels supplying the lower extremities in the arterial system. In the vicinity of bifurcations flow tends to separate forming re-circulation regions. In addition, due to the pulsatile character of blood flow during the deceleration part of the cycle, the flow becomes unstable and transition to turbulence may occur. Vascular stents provide a novel method in treatment of atherosclerotic vessels. Although stents have dramatically decreased the re-stenosis rate of vessels compared to balloon-angioplasty, restenosis still occurs in 25-30% of coronary implanted stents. Understanding how stents influence flow patterns may lead to more hemodynamically compatible stent designs that alleviate thrombus formation and promote endothelialization. The first study employed time-resolved Digital Particle Image Velocimetry (DPIV) to compare the hemodynamic performance of two stents in a compliant vessel. The first stent was a rigid insert, representing an extreme compliance mismatch. The second stent was a commercially available nitinol stent with some flexural characteristics. DPIV showed that compliance mismatch promotes the formation of a ring vortex in the vicinity of the stent. Larger compliance mismatch increased both the size and residence time of the ring vortex, and introduced in-flow stagnation points. These results provide detailed quantitative evidence of the hemodynamic effect of stent mechanical properties. Better understanding of these characteristics will provide valuable information for modifying stent design in order to promote long-term In the second study, DPIV was utilized to explore the fluid dynamics phenomena in a symmetric compliant bifurcation. We studied the effects of the Womersley and the Reynolds numbers under pulsatile flow conditions. New insight of the fluid mechanics is revealed. The flow topology results indicate that the formation of coherent vortices in the vicinity of the bifurcation apex is governed by physical process that dictates the energy and strength of the formed vortices. This is manifested by the identification of a characteristic dimensionless time-scale that combines the impulsive vortex formation with the inertia of the unsteady flow.
Master of Science

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Frissell, Nathaniel A. "Ionospheric Disturbances: Midlatitude Pi2 Magnetospheric ULF Pulsations and Medium Scale Traveling Ionospheric Disturbances." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/74976.

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The ionosphere is an electrically charged atmospheric region which is coupled to the sun, the magnetosphere, and the neutral atmosphere. The ionospheric state can significantly impact technological systems, especially those which utilize radio frequency energy. By studying ionospheric disturbances, it is possible to gain a deeper understanding of not only the ionosphere itself, but also the natural and technological systems it is coupled to. This dissertation research utilizes high frequency (HF) radio remote sensing techniques to study three distinct types of ionospheric disturbances. First, ground magnetometers and a new mid latitude SuperDARN HF radar at Blackstone, Virginia are used to observe magnetospheric Pi2 ultra low frequency (ULF) pulsations in the vicinity of the plasmapause. Prior to these pulsations, two Earthward moving fast plasma flows were detected by spacecraft in the magnetotail. Signatures of inner magnetospheric compression observed by the Blackstone radar provide conclusive evidence that the plasma flow bursts directly generated the ground Pi2 signature via a compressional wave. This mechanism had previously been hypothesized, but never confirmed. Next, ten SuperDARN radars in the North American Sector are used to investigate the sources and characteristics of atmospheric gravity waves (AGW) associated medium scale traveling ionospheric disturbances (MSTIDs) at both midlatitudes and high latitudes. Consistent with prior studies, the climatological MSTID population in both latitudinal regions was found to peak in the fall and winter and have a dominant equatorward propagation direction. Prior studies suggested these MSTIDs were caused by mechanisms associated with auroral and space weather activity; however, it is shown here that the AE and Sym-H indices are poorly correlated with MSTID observations. A new, multi-week timescale of MSTID activity is reported. This leads to the finding that MSTID occurrence is highly correlated with an index representative of polar vortex activity, possibly controlled by a filtering mechanism that is a function of stratospheric neutral wind direction. Finally, a case study of a radio blackout of transionospheric HF communications caused by an X2.9 class solar flare is presented. This study demonstrates the potential of a novel technique employing signals of opportunity and automated receiving networks voluntarily created by an international community of amateur radio operators.
Ph. D.

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Taylor, Diana L. "A nursing intervention for perimenstrual turmoil : a longitudinal therapeutic trial /." Thesis, Connect to this title online; UW restricted, 1988. http://hdl.handle.net/1773/7235.

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Karlsson, Berndt. "Metabolic disturbances in shift workers." Doctoral thesis, Umeå : Univ, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-242.

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Nedic, Dusko P. "Simulation of large system disturbances." Thesis, University of Manchester, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488379.

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Rose, Sarah Jane. "Spider Community Response to Disturbances." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492759846303432.

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Dogwiler, Toby J. "Fluvial disturbances in karst streams /." free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3060093.

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Harper, David G. "Circadian rhythm disturbances in advanced dementia /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2000.

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Thesis (Ph.D.)--Tufts University, 2000.
Adviser: David Harder. Submitted to the Dept. of Psychology. Includes bibliographical references (leaves 90-116). Access restricted to members of the Tufts University community. Also available via the World Wide Web;

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Wixner, Jonas. "Gastrointestinal disturbances in hereditary transthyretin amyloidosis." Doctoral thesis, Umeå universitet, Institutionen för folkhälsa och klinisk medicin, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-88745.

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Background Transthyretin amyloid (ATTR) amyloidosis is a systemic disorder caused by amyloid deposits formed by misfolded transthyretin (TTR) monomers. Two main forms exist – wild-type and hereditary ATTR amyloidosis, the latter associated with TTR gene mutations. Wild-type ATTR amyloidosis has a late onset and primarily cardiac manifestations, whereas hereditary ATTR amyloidosis is a rare autosomal dominant condition with a considerable phenotypic diversity. Both disorders are present all over the world, but endemic areas of the hereditary form are found in Sweden, Portugal, Brazil and Japan. Gastrointestinal (GI) complications are common in hereditary ATTR amyloidosis and play an important role in the patients’ morbidity and mortality. Malfunction of the autonomic and enteric nervous systems has been proposed to contribute to the GI disturbances, but the underlying mechanisms have not been fully elucidated. The aims of this thesis were to assess the prevalence of GI disturbances for different subtypes of ATTR amyloidosis, to further explore the mechanisms behind these disturbances, and to evaluate the outcome of the patients’ GI function after liver transplantation, which currently is the standard treatment for hereditary ATTR amyloidosis. Methods The Transthyretin Amyloidosis Outcomes Survey (THAOS) is the first global, multicenter, longitudinal, observational survey that collects data on patients with ATTR amyloidosis. THAOS enrollment data were used to assess the prevalence of GI symptoms and to evaluate their impact on nutritional status (mBMI) and health-related quality of life (EQ-5D Index Score). Data from routine investigations of heart-rate variability and cardio-vascular response to tilt tests were utilized to evaluate the impact of autonomic neuropathy on the scintigraphically measured gastric emptying half-times in Swedish patients with hereditary ATTR amyloidosis. Gastric wall autopsy specimens from Japanese patients with hereditary ATTR amyloidosis and Japanese non-amyloidosis controls were analyzed with immunohistochemistry and computerized image analysis to assess the densities of interstitial cells of Cajal (ICC) and nervous tissue. Data from gastric emptying scintigraphies and validated questionnaires were used to evaluate the outcome of Swedish patients’ GI function after liver transplantation for hereditary ATTR amyloidosis. Results Sixty-three percent of the patients with TTR mutations and 15 % of those with wild-type ATTR amyloidosis reported GI symptoms at enrollment into THAOS. Subsequent analyses focused on patients with TTR mutations and, among them, unintentional weight loss was the most frequent symptom (32 %) followed by early satiety (26 %). Early-onset patients (<50 years of age) reported GI symptoms more frequently than late-onset cases (70 % vs. 50 %, p <0.01), and GI symptoms were more common in patients with the V30M mutation than in those with non-V30M mutations (69 % vs. 56 %, p <0.01). Both upper and lower GI symptoms were significant negative predictors of nutritional status and health-related quality of life (p <0.01 for both). Weak but significant correlations were found between gastric emptying half-times and the function of both the sympathetic (rs = -0.4, p <0.01) and parasympathetic (rs = -0.3, p <0.01) nervous systems. The densities of c-Kit-immunoreactive ICC were significantly lower in the circular (median density 0.0 vs. 2.6, p <0.01) and longitudinal (median density 0.0 vs. 1.8, p <0.01) muscle layers of the gastric wall in patients compared to controls. Yet, no significant differences in protein gene product 9.5-immunoreactive nervous cells were found between patients and controls either in the circular (median density 3.0 vs. 6.8, p = 0.17) or longitudinal (median density 1.4 vs. 2.5, p = 0.10) muscle layers. Lastly, the patients’ GI symptoms scores had increased slightly from before liver transplantation to the follow-ups performed in median two and nine years after transplantation (median score 7 vs. 10 vs. 13, p <0.01). However, their gastric emptying half-times (median half-time 137 vs. 132 vs. 125 min, p = 0.52) and nutritional statuses (median mBMI 975 vs. 991 vs. 973, p = 0.75) were maintained at follow-ups in median two and five years after transplantation. Conclusion GI disturbances are common in hereditary ATTR amyloidosis and have a negative impact on the patients’ nutritional status and health-related quality of life. Fortunately, a liver transplantation appears to halt the progressive GI involvement of the disease, although the patients’ GI symptoms tend to increase after transplantation. An autonomic neuropathy and a depletion of gastrointestinal ICC seem to contribute to the GI disturbances, but additional factors must be involved.

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Bajramivic, Armin, and Berwar Kahraman. "Minimizing disturbances in pipe replacement projects." Thesis, KTH, Fastigheter och byggande, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231605.

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The market for maintenance of dwellings in the construction industry is only getting more significant due to the time factor. Dwellings are only getting older, and demands for refurbishment are getting more obligatory for tenant-owned cooperatives. This study examines the project manager’s approach when dealing with tenant-owned cooperatives and the management of pipe replacement. What risks and factors that are important to identify to achieve a possible decrease in disturbances in pipe replacement projects. To answer the purpose and the research questions asked, eight interviews were conducted. The interviews were project managers with different experience level in the field of pipe replacement. The questions asked were based on the theoretical aspect of this study to examine further strategies that could help to achieve a successful project. The result from the interviewees was then analyzed and compressed to understand main factors and identify strategies to decrease disturbance during a pipe replacement project. The result from this master thesis indicates that a well-functioned communication prevents unpredictable risks together with a comprehensive pre-study. When dealing with a non-professional client, the right approach and educational level have to be established in the first interaction. When asked to rank the critical success factors, the most important ones were; Human-related factors, Project procedures, and Project-related factors. This consequently, implies which areas that are important for a project manager. As for the result of using risk management in pipe replacement projects, it could be regarded as either the most important or one very important tool to generate a successful project.
Marknaden för underhåll av bostadsrättföreningars bostäder i byggbranschen blir bara allt större på grund av tidsfaktorn. Bostäder blir bara äldre och krav på renovering blir mer obligatorisk för bostadsrättsföreningarna. Denna studie undersöker projektledarens synsätt om hur man hanterar bostadsrättföreningar och projektledningen av stambyte. Vilka risker och faktorer som är viktiga att identifiera för att uppnå så nära som möjligt ett störningsfritt projekt. För att svara på syftet och frågeställningar har åtta intervjuer genomförts. Intervjuerna var med projektledare med olika erfarenhetsnivåer inom stambyte. Frågorna var baserad på den teoretiska aspekten av denna studie för att undersöka strategier som skulle kunna bidra till att uppnå ett framgångsrikt projekt. Resultatet från intervjuerna analyserades och undersöktes för att sedan förstå huvudfaktorerna och därmed identifieringsstrategier för att minska störningarna under ett stambytesprojekt. Resultatet av detta examensarbete visar att en väl fungerande kommunikation hindrar oförutsägbara risker med en djup förstudie. När projekt ledarna arbetar med en icke-professionell beställare måste man redan från början etablera rätt inställning. När de som intervjuades frågades om att rangordna vilka av de kritiska framgångsfaktorerna som var de viktigaste, var följande resultat; Mänskliga faktorer, upphandlingsprocesser och Projektrelaterade faktorer. Följaktligen, innebär vilket område som är viktigt för en projektledare. När det gäller resultatet av att använda riskhantering i rörbytesprojekt, kan det betraktas som antingen det viktigaste eller ett mycket viktigt verktyg för att skapa ett framgångsrikt projekt.

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Findlay, Ewan Donald. "Periodic dielectric disturbances and novel optics." Thesis, University of St Andrews, 1995. http://hdl.handle.net/10023/13612.

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Several possible methods for creating permanent and temporary periodic dielectric disturbances and their application to optics have been examined. The coupled mode theory is used to describe the travelling wave electro-optic diffractor (TWEOD) proposed by Dawber et al. A basic theoretical model of the TWEOD is presented and developed to give the design parameters for the construction of a working barium titanate TWEOD operating at 10 GHz. The coupled mode theory is also used to describe the dielectric disturbances created by pump beam interference patterns within a laser medium. Pump architectures which yield a periodic disturbance and thus create temporary diffraction gratings are analysed. Permanent dielectric disturbances can be generated in glass heated to temperatures above the transformation point. Some possible methods for imposing both uniform and periodic dielectric disturbances on glass, which are generated by imposing stresses on the glass whilst it is at its transformation temperature are proposed. Uniformly pre-stressed glass can be used to improve the angular response of glass acousto-optic diffractors. Periodically prestressed glass forms a permanent acousto-optic diffraction grating. Acoustic standing waves may also be used to induce periodic structural change in other transparent media and on the surface of etchable substrates. Such acoustically induced structures may be used as permanent diffraction gratings and holograms. A potential application for some of the novel devices described in this work is illustrated in the implementiation of an optical frequency division multiplexer ("optiplexer") for video signals (3 dB Bandwidth of 6 MHz) using acousto-optic frequency shifting techniques. This is a times six improvement on the channel bandwidth of 1 MHz for the optiplexer achieved by Dawber et al.

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Lee, Keumjin. "Airspace complexity: airspace response to disturbances." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22552.

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Thesis (Ph. D.)--Aerospace Engineering, Georgia Institute of Technology, 2008.
Committee Chair: Pritchett, Amy; Committee Co-Chair: Feron, Eric; Committee Member: Clarke, John-Paul; Committee Member: Tsiotras, Panagiotis; Committee Member: Yang, Bong-Jun

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Zhu, Jinlin Wu Theodore Y. T. "Internal solitons generated by moving disturbances /." Diss., Pasadena, Calif. : California Institute of Technology, 1986. http://resolver.caltech.edu/CaltechETD:etd-03122008-080220.

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Lindberg, Laura. "The refrative components in binocularity disturbances." Helsinki : University of Helsinki, 1999. http://ethesis.helsinki.fi/julkaisut/laa/kliin/vk/lindberg/.

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McMahon, Kathryn. "Recovery of subtropical seagrasses from natural disturbances /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19102.pdf.

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Feiler, Matthias J. "Adaptive control in the presence of disturbances." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=97276691X.

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Reason, Christopher James Charles. "Coastally trapped disturbances in the lower atmosphere." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29267.

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Coastally trapped disturbances that propagate in the marine layers of western North America, Southern Africa and southeastern Australia are examined. These areas of the world are considered to be most favourable for the propagation of the disturbances because they all possess pronounced subsidence inversions and barrierlike coastal mountain ranges. Trapping of the disturbance energy within a coastal zone then occurs through this inversion being situated below the mountain crests and through Coriolis effects on the propagating disturbances themselves. Coriolis effects are also responsible for the propagation occurring with the coast on the right (left) in the Northern (Southern) Hemisphere. As this propagation occurs, marked changes in the inversion height and local weather conditions below the inversion are observed. These changes are similar in all three regions with the exception that the inversion is raised in the North American and Australian cases but lowered for the South African disturbances. This difference is shown to arise because the forcing flow is on- or alongshore for the former but offshore in Southern Africa. It is argued that the fundamental dynamics of these disturbances are identical (hydrostatic and semigeostrophic) in each area but that regional differences in the forcing and boundary conditions are responsible for the various manifestations of the disturbances. Based on the observed commonality between the three theory of coastally trapped disturbances is developed from the shallow water equations for a rotating, stratified and flat-bottomed fluid. It is shown that the theory will admit two types of solution, a Kelvin wave and a coastal gravity current, which if higher order effects are included, are found to be related. Comparisons of the different forcings and boundary conditions are made to show the potential importance of nonlinearities. It is concluded that the Southern African case is best described as a continuously forced, linear Kelvin wave, while the North American and Australian disturbances exhibit both gravity current and nonlinear Kelvin wave characteristics. In each case, the theoretical predictions of the evolution time scale, propagation characteristics and speed are shown to be consistent with the available observations.
Arts, Faculty of
Geography, Department of
Graduate

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Baines, Gary. "The Port Elizabeth disturbances of October, 1920." Thesis, Rhodes University, 1988. http://hdl.handle.net/10962/d1001858.

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Chapter one suggests thet trade and merchant capital, which were crucial to Port Elizabeth's economic development during the nineteenth century, was subsumed by the rise of manufactures and industrial capital after the First World War. Industrial expansion was cut short by the post-war recession, which caused un- and underemployment. The black worker, who experienced a severe loss in real earnings on account of the increased cost of living, became involved in a struggle with employers for wage increases. Chapter two shows how the policy of segregation was applied in Port Elizabeth, which meant that the workers were subjected to an increasing degree of control and regulation of their daily lives. The conditions of reproduction in the black townships fostered inter-racial and cross-class mobilisation which culminated in the formation of a general labour union, the Port Elizabeth Industrial and Commercial Workers' Union (PEICWU). Chapter three will suggest links between the tradition in Port Elizabeth of worker resistance and the unionisation of black workers in the post-war period. Thus, the first three chapters attempt to provide a historical perspective for analysing the underlying causes of the 1920 Port Elizabeth disturbances. The immediate cause of the disturbances was the arrest of the Union leader, Masabalala, after he called for a general strike. Chapter four will show how the intervention of the local authorities provoked a spontaneous act of defiance on the part of Union members. A demonstration outside the Baakens Street Police Station to demand the release of Masabalala, precipitated the tragic shootings of 23 October 1920. The repressive violence which left 22 dead (with two further deaths resulting indirectly from the incident) was unprecedented in South African history. The resolution of the crisis brought the workers no nearer to obtaining a reasonable settlement of the wage issue. If anything, the resolve of employers to deny wage demands was hardened by the actions of the local authorities, who attributed the disturbances to ' agitation '. Such thinly-disguised justifications of the shootings by the dominant classes, however, provoked recriminations from other quarters. Chapter five examines the legal and political ramifications of the Port Elizabeth shootings. The circumstances of the shootings prompted the Smuts Government to appoint a Commission of Enquiry in the face of public pressure. The Commission found that the Police and vigilantes were largely to blame for the high death toll. But the Government's 'whitewash' of the findings could not absolve the Police from culpability entirely, nor could it sidestep its own responsibility and liability to victims of the shootings. Finally, in Chapter six, an attempt will be made to assess the long term impact of the shootings on the PElCU and the black labour movement in Port Elizabeth generally. The outcome of the episode was a victory for employers, which dealt a body blow to worker organisation which only became resurgent in the 1950s.

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com, Daphnesu16@yahoo, and Wanqi Daphne Su. "Psychological Stress and Vascular Disturbances in Rosacea." Murdoch University, 2009. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090313.115603.

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Rosacea is a chronic skin disorder, characterized by redness and flushing of the cheeks, nose, chin or forehead. It has been proposed that rosacea is a result of frequent blushing (Miller, 1921; Klaber & Whittkower, 1939). However, the relationship between rosacea and blushing is uncertain. The aim of the present research was to investigate the relationship between psychological stress and vascular disturbances in rosacea. Five studies were conducted. The first study explored the relationship between rosacea and mental health while the next two investigated vascular responses in rosacea sufferers and controls to acetylcholine (which induces endothelial vasodilatation and axon reflexes) and psychological stress (embarrassment). The fourth study aimed to examine the relationship between psychological indicators and rosacea symptoms on a daily basis. The fifth study consisted of three case studies looking at the use of Cognitive Behavioural Therapy (CBT) and Task Concentration Training (TCT) with rosacea sufferers presenting with social anxiety and fear of blushing symptoms. In study 1, sixty-two participants were asked to complete the Blushing Propensity Scale (BPS), Fear of Negative Evaluation (FNE), Depression, Anxiety and Stress Scale (DASS), Social Interaction Anxiety Scale (SIAS) and Social Phobia Scale (SPS). Outcomes from the first study indicated that Type 2 rosacea sufferers (n= 12) perceived themselves as blushing more frequently and intensely than Type 1 rosacea sufferers (n=19) or controls (n=31). This suggested that Type 2 rosacea sufferers experiencing frequent blushing may have a lower sensitivity threshold to blushing episodes. In addition, Type 2 rosacea sufferers perceived themselves as more stressed than Type 1 rosacea sufferers or controls, possibly indicating that managing the condition can be stressful. Contrary to previous reports (Gupta et al., 2006; National Rosacea Society, 2005) severity of rosacea was not associated with depression, social anxiety or fear of negative evaluation. However, a few participants who reported high social anxiety and stress scores were offered psychological intervention (Study 5). The aim of the second study was to investigate vascular responses in rosacea sufferers. Cutaneous endothelial and axon reflex function was assessed using an acetylcholine dose response curve. The axon reflex was assessed by inducing a flare with ACh iontophoresis. Outcomes from this study indicated that Type 2 rosacea sufferers had a greater axon reflex response than Type 1 rosacea sufferers. Thus over-reactivity of the axon reflex in Type 2 rosacea sufferers might contribute to prolonged vasodilatation. However, cutaneous endothelial responses to ACh were similar in rosacea and control groups. The results suggested that neural pathways mediated the flushing response rather than cutaneous endothelial function. The third study investigated facial blood flow while participants attempted laboratory induced embarrassment tasks. Type 2 rosacea sufferers were found to have a greater blood flow in the facial region than Type 1 rosacea sufferers during singing and speech tasks, suggesting that Type 2 rosacea sufferers blushed more than type 1 rosacea sufferers or controls. Furthermore, Type 2 rosacea sufferers reported higher embarrassment and blushing ratings than Type 1 rosacea sufferers. This indicated that Type 2 rosacea sufferers perceived themselves as emotionally more aroused than other participants. Taken together, it would appear that a combination of physiological and cognitive factors increased facial blood flow in Type 2 rosacea sufferers in laboratory induced embarrassment tasks. The fourth study explored the relationship between stress and symptoms of rosacea. Using a diary, 15 rosacea sufferers recorded their stress, anxiety and mood and their intensity of rosacea symptoms daily. Stress was associated with increased stinging/facial redness on the same day for 1 to 2 months. Furthermore, it was associated with increased stinging ratings the next day. However, feeling anxious or having low mood was not related to increase stinging the next day. The presence of increased stress found in rosacea participants on the day where stinging and redness occurred should be taken into consideration when formulating psychological interventions for rosacea sufferers. In study 5, individual psychological intervention was provided to three participants experiencing stress, fear of blushing and social anxiety symptoms. Cognitive Behavioural Therapy (CBT) and Task Concentration Training (TCT) were helpful in managing stress, anxiety and fear of blushing symptoms in individual rosacea sufferers. Encouragingly, all participants reported a gain in their repertoire of strategies and showed a decrease in anxiety symptoms on assessment questionnaires following their intervention. Replication of the intervention protocol and investigation of other psychological approaches are required to establish best practise outcome for rosacea sufferers who require psychological interventions. The present findings suggest that over-reactivity of axon reflexes contributes to facial flushing. In addition, emotional flushing in rosacea sufferers appears to be maintained by a combination of cognitive and physiological factors. On a clinical level, the study recommends that emotional stress associated with facial flushing in rosacea sufferers to be targeted for psychological intervention.

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Westerlund, Nils. "Counteracting acoustic disturbances in human speech communication /." Karlskrona : Blekinge Institute of Technology, 2006. http://www.bth.se/fou/Forskinfo.nsf/Sok/343efb30a0905236c125715d002ec160!OpenDocument.

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Qiu, Jie. "Study of driver models forside wind disturbances." Thesis, KTH, Fordonsdynamik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-157504.

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As the development of highways, it is quite normal for buses running in a speed around 100km/h. When buses are running in a high speed, they may suffer from the influence of side wind disturbances at anytime. Sometimes, it may result in traffic accidents. Therefore, the study of bus stability under side wind disturbances becomes more and more important. Due to restrictions of real tests, computer simulation can be used to study this subject. The bus side wind response character is reflected through the driver’s manoeuvre , so open-loop analysis is hard to give a comprehensive evaluation of the side wind stability of the bus. Therefore, closed-loop analysis is studied in this thesis. An ADAMS bus model and a side wind force model are developed in this thesis, along with two driver models, the PID control model and the preview curvature model. The driver models are built in Simulink and co-simulation between ADAMS/View and Simulink is conducted. The results of co-simulation show that the two driver models can both control the bus from deviating from the desired course under side wind disturbances. The PID control model is simple and shows a very good control effect. The maximum lateral displacement of the bus by PID control model is just 0.0205m under maximum side wind load 1000N and 2500Nm when preview time is 1.2s, while it is 0.0702m by preview curvature model, however, it is difficult to determine the coefficients Kd, Kp, and Ki in the PID controller. The preview curvature model also shows a good control effect in terms of the maximum lateral displacement and yaw angle of the bus. Comparing these two models, the PID control model is more sensitive to deviations, with quicker response and larger steering input. The bus model system is stable under side wind disturbances. Through driver ’s proper steering manoeuvre, the bus is well controlled. The closed-loop analysis is a good method to study the bus stability under side wind disturbances.

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Pritanto, I. Erwin. "Managing unavoidable disturbances in ship manufacturing systems." Thesis, University of Newcastle Upon Tyne, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397529.

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Tse, David N. C. "Optimal and robust identification under bounded disturbances." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/13850.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1991.
Includes bibliographical references (leaves 69-71).
by David Ngar Ching Tse.
M.S.

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Pillay, Victoria. "Sodium and potassium disturbances in childhood diarrhoea." Doctoral thesis, University of Cape Town, 2006. http://hdl.handle.net/11427/2792.

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Dansie, Brian L. "Micronutrition and Enamel Disturbances in Bronchopulmonary Dysplasia." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1372026150.

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Reicher, Christopher Phillip. "Three essays on estimation of policy disturbances." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3307184.

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Thesis (Ph. D.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed Aug. 13, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.

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Parsons, Antony Cozart. "Automatic location of transient power quality disturbances /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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Hiyadutuje, Alicreance. "Ionospheric disturbances during magnetic storms at SANAE." Thesis, Rhodes University, 2017. http://hdl.handle.net/10962/54956.

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The coronal mass ejections (CMEs) and solar flares associated with extreme solar activity may strike the Earth's magnetosphere and give rise to geomagnetic storms. During geomagnetic storms, the polar plasma dynamics may influence the middle and low-latitude ionosphere via travelling ionospheric disturbances (TIDs). These are wave-like electron density disturbances caused by atmospheric gravity waves propagating in the ionosphere. TIDs focus and defocus SuperDARN signals producing a characteristic pattern of ground backscattered power (Samson et al., 1989). Geomagnetic storms may cause a decrease of total electron content (TEC), i.e. a negative storm effect, or/and an increase of TEC, i.e. a positive storm effect. The aim of this project was to investigate the ionospheric response to strong storms (Dst < -100 nT) between 2011 and 2015, using TEC and scintillation measurements derived from GPS receivers as well as SuperDARN power, Doppler velocity and convection maps. In this study the ionosphere's response to geomagnetic storms is determined by the magnitude and time of occurrence of the geomagnetic storm. The ionospheric TEC results of this study show that most of the storm effects observed were a combination of both negative and positive per storm per station (77.8%), and only 8.9% and 13.3% of effects on TEC were negative and positive respectively. The highest number of storm effects occurred in autumn (36.4%), while 31.6%, 28.4% and 3.6% occurred in winter, spring and summer respectively. During the storms studied, 71.4% had phase scintillation in the range of 0.7 - 1 radians, and only 14.3% of the storms had amplitude scintillations near 0.4. The storms studied at SANAE station generated TIDs with periods of less than an hour and amplitudes in the range 0.2 - 5 TECU. These TIDs were found to originate from the high-velocity plasma flows, some of which are visible in SuperDARN convection maps. Early studies concluded that likely sources of these disturbances correspond to ionospheric current surges (Bristow et al., 1994) in the dayside auroral zone (Huang et al., 1998).

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Ghufran, Safeena. "Trauma memories and disturbances in autobiographical memory." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6928/.

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Su, Daphne. "Psychological stress and vascular disturbances in Rosacea." Thesis, Su, Daphne (2008) Psychological stress and vascular disturbances in Rosacea. Professional Doctorate thesis, Murdoch University, 2008. https://researchrepository.murdoch.edu.au/id/eprint/464/.

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Rosacea is a chronic skin disorder, characterized by redness and flushing of the cheeks, nose, chin or forehead. It has been proposed that rosacea is a result of frequent blushing (Miller, 1921; Klaber & Whittkower, 1939). However, the relationship between rosacea and blushing is uncertain. The aim of the present research was to investigate the relationship between psychological stress and vascular disturbances in rosacea. Five studies were conducted. The first study explored the relationship between rosacea and mental health while the next two investigated vascular responses in rosacea sufferers and controls to acetylcholine (which induces endothelial vasodilatation and axon reflexes) and psychological stress (embarrassment). The fourth study aimed to examine the relationship between psychological indicators and rosacea symptoms on a daily basis. The fifth study consisted of three case studies looking at the use of Cognitive Behavioural Therapy (CBT) and Task Concentration Training (TCT) with rosacea sufferers presenting with social anxiety and fear of blushing symptoms. In study 1, sixty-two participants were asked to complete the Blushing Propensity Scale (BPS), Fear of Negative Evaluation (FNE), Depression, Anxiety and Stress Scale (DASS), Social Interaction Anxiety Scale (SIAS) and Social Phobia Scale (SPS). Outcomes from the first study indicated that Type 2 rosacea sufferers (n= 12) perceived themselves as blushing more frequently and intensely than Type 1 rosacea sufferers (n=19) or controls (n=31). This suggested that Type 2 rosacea sufferers experiencing frequent blushing may have a lower sensitivity threshold to blushing episodes. In addition, Type 2 rosacea sufferers perceived themselves as more stressed than Type 1 rosacea sufferers or controls, possibly indicating that managing the condition can be stressful. Contrary to previous reports (Gupta et al., 2006; National Rosacea Society, 2005) severity of rosacea was not associated with depression, social anxiety or fear of negative evaluation. However, a few participants who reported high social anxiety and stress scores were offered psychological intervention (Study 5). The aim of the second study was to investigate vascular responses in rosacea sufferers. Cutaneous endothelial and axon reflex function was assessed using an acetylcholine dose response curve. The axon reflex was assessed by inducing a flare with ACh iontophoresis. Outcomes from this study indicated that Type 2 rosacea sufferers had a greater axon reflex response than Type 1 rosacea sufferers. Thus over-reactivity of the axon reflex in Type 2 rosacea sufferers might contribute to prolonged vasodilatation. However, cutaneous endothelial responses to ACh were similar in rosacea and control groups. The results suggested that neural pathways mediated the flushing response rather than cutaneous endothelial function. The third study investigated facial blood flow while participants attempted laboratory induced embarrassment tasks. Type 2 rosacea sufferers were found to have a greater blood flow in the facial region than Type 1 rosacea sufferers during singing and speech tasks, suggesting that Type 2 rosacea sufferers blushed more than type 1 rosacea sufferers or controls. Furthermore, Type 2 rosacea sufferers reported higher embarrassment and blushing ratings than Type 1 rosacea sufferers. This indicated that Type 2 rosacea sufferers perceived themselves as emotionally more aroused than other participants. Taken together, it would appear that a combination of physiological and cognitive factors increased facial blood flow in Type 2 rosacea sufferers in laboratory induced embarrassment tasks. The fourth study explored the relationship between stress and symptoms of rosacea. Using a diary, 15 rosacea sufferers recorded their stress, anxiety and mood and their intensity of rosacea symptoms daily. Stress was associated with increased stinging/facial redness on the same day for 1 to 2 months. Furthermore, it was associated with increased stinging ratings the next day. However, feeling anxious or having low mood was not related to increase stinging the next day. The presence of increased stress found in rosacea participants on the day where stinging and redness occurred should be taken into consideration when formulating psychological interventions for rosacea sufferers. In study 5, individual psychological intervention was provided to three participants experiencing stress, fear of blushing and social anxiety symptoms. Cognitive Behavioural Therapy (CBT) and Task Concentration Training (TCT) were helpful in managing stress, anxiety and fear of blushing symptoms in individual rosacea sufferers. Encouragingly, all participants reported a gain in their repertoire of strategies and showed a decrease in anxiety symptoms on assessment questionnaires following their intervention. Replication of the intervention protocol and investigation of other psychological approaches are required to establish best practise outcome for rosacea sufferers who require psychological interventions. The present findings suggest that over-reactivity of axon reflexes contributes to facial flushing. In addition, emotional flushing in rosacea sufferers appears to be maintained by a combination of cognitive and physiological factors. On a clinical level, the study recommends that emotional stress associated with facial flushing in rosacea sufferers to be targeted for psychological intervention.

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Su, Daphne. "Psychological stress and vascular disturbances in rosacea /." Murdoch University Digital Theses Project, 2008. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20090313.115603.

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Wu, Chang-Shiou. "Mechanics of sampling disturbances in clay soils." Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185458.

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This research provides an insight into the quality of a soil sample during the penetration of a soil sampler. The investigation of the mechanical disturbances in a clay soil is conducted by using an updated Lagrangian finite element formulation with the 2nd Piola-Kirchhoff stress rate (the Truesdell stress increment) to account for the large deformation behavior near the sampling tube. The penetration of the sampler is simulated by spliting a group of nodes ahead of the penetration route up to a sufficient depth and applying incremental deformation to match the geometric configuration of the sampling tube. Consolidation effect is included to account for the rate of penetration. Thin-layer elements are added into the inside wall of the sampling tube to model the soil-sampler interface. The modified Cam-clay model is used to simulate the behavior of the soils. An experimental study was conducted to study the variations of stresses and pore water pressures at the soil-sampler interface. The numerical results show that (1) soil samples are subjected to three distinct stages of vertical strain history, compression-extension-recompression. The first stage of compression, in particular, causes irrecoverable changes in the virgin soil properties of the soil; (2) the undrained shear strength of a disturbed sample reconsolidated to the in situ stress condition is larger than the virgin soil for normally consolidated soils but it is smaller for over consolidated soils; (3) the sampling disturbances due to friction at the soil-sampler interface increase as the sampler penetrates the soil. As a result, long samples will be seriously degraded; (4) the increase of the rate of penetration can reduce the degree of disturbances; (5) the piston sampler induces much larger disturbances than the open-drive sampler.

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SCODINA, STEFANO. "Observation and control of PDE with disturbances." Doctoral thesis, Università degli Studi di Cagliari, 2012. http://hdl.handle.net/11584/266149.

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In this Thesis, the problem of controlling and Observing some classes of distributed parameter systems is addressed. The particularity of this work is to consider partial differential equations (PDE) under the effect of external unknown disturbances. We consider generalized forms of two popular parabolic and hyperbolic infinite dimensional dynamics, the heat and wave equations. Sliding-mode control is used to achieve the control goals, exploiting the robustness properties of this robust control technique against persistent disturbances and parameter uncertainties.

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Ando, Junior Oswaldo Hideo. "Desenvolvimento de uma metodologia para identificar e quantificar distúrbios da qualidade da energia elétrica." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/18419.

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Este trabalho apresenta uma metodologia para análise e monitoração da qualidade da energia elétrica, através da identificação e quantificação dos distúrbios eletromagnéticos. A metodologia utiliza técnicas de processamento digital de sinais, possibilitando a construção de filtros digitais, a detecção de eventos e a estimativa da freqüência dos sinais elétricos analisados. Os principais distúrbios da qualidade definidos pelas normas da ANEEL e do ONS são quantificados através do algoritmo proposto. O programa desenvolvido foi testado usando formas de ondas com distúrbios previamente conhecidos para sua validação. Analisando formas de onda obtidas de medições em campo verificou-se a robustez do algoritmo frente a ruídos e outros fenômenos vinculados à qualidade da energia presentes em medições reais. Esta pesquisa apresenta um programa eficaz e prático que pode ser utilizado no desenvolvimento de um novo equipamento de medição dos distúrbios da QEE. Os resultados obtidos através da análise de dados (sintetizados e medições de campo) validaram o programa proposto.
This dissertation presents a methodology for detection and quantification of power quality disturbances. Digital signal processing (DSP) is applied to simulated and measured disturbances. The use of DSP enables the construction of digital filters for the detection of events, and the estimation of the frequency of voltage and current signals. The disturbances set by ANEEL and ONS standards are quantified by the proposed algorithm. The program developed was tested using simulated disturbance for its validation. Field measurements were used to assess the robustness of the algorithm against signal noise and other disturbances. This research presents effective and practical software that can be used to develop a new device for measuring the disturbances of Power Quality. The results obtained through the analysis of data (simulated and field measurements) validated the proposed algorithm.

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Khatir, Zinedine. "Discrete vortex modelling of near-wall flow structures in turbulent boundary layers." Thesis, University of Warwick, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364578.

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Men, Kun. "Long term voltage stability analysis for small disturbances." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2499.

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Törnqvist, David. "Statistical Fault Detection with Applications to IMU Disturbances." Licentiate thesis, Linköping University, Linköping University, Automatic Control, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7094.

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This thesis deals with the problem of detecting faults in an environment where the measurements are affected by additive noise. To do this, a residual sensitive to faults is derived and statistical methods are used to distinguish faults from noise. Standard methods for fault detection compare a batch of data with a model of the system using the generalized likelihood ratio. Careful treatment of the initial state of the model is quite important, in particular for short batch sizes. One method to handle this is the parity-space method which solves the problem by removing the influence of the initial state using a projection.

In this thesis, the case where prior knowledge about the initial state is available is treated. This can be obtained for example from a Kalman filter. Combining the prior estimate with a minimum variance estimate from the data batch results in a smoothed estimate. The influence of the estimated initial state is then removed. It is also shown that removing the influence of the initial state by an estimate from the data batch will result in the parity-space method. To model slowly changing faults, an efficient parameterization using Chebyshev polynomials is given.

The methods described above have been applied to an Inertial Measurement Unit, IMU. The IMU usually consists of accelerometers and gyroscopes, but has in this work been extended with a magnetometer. Traditionally, the IMU has been used to estimate position and orientation of airplanes, missiles etc. Recently, the size and cost has decreased making it possible to use IMU:s for applications such as augmented reality and body motion analysis. Since a magnetometer is very sensitive to disturbances from metal, such disturbances have to be detected. Detection of the disturbances makes compensation possible. Another topic covered is the fundamental question of observability for fault inputs. Given a fixed or linearly growing fault, conditions for observability are given.

The measurements from the IMU show that the noise distribution of the sensors can be well approximated with white Gaussian noise. This gives good correspondence between practical and theoretical results when the sensor is kept at rest. The disturbances for the IMU can be approximated using smooth functions with respect to time. Low rank parameterizations can therefore be used to describe the disturbances. The results show that the use of smoothing to obtain the initial state estimate and parameterization of the disturbances improves the detection performance drastically.

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Eklöf, Johan S. "Anthropogenic Disturbances and Shifts in Tropical Seagrass Ecosystems." Doctoral thesis, Stockholm University, Department of Systems Ecology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7285.

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Seagrasses constitute the basis for diverse and productive ecosystems worldwide. In East Africa, they provide important ecosystem services (e.g. fisheries) but are potentially threatened by increasing resource use and lack of enforced management regulations. The major aim of this PhD thesis was to investigate effects of anthropogenic distur-bances, primarily seaweed farming and coastal fishery, in East African seagrass beds. Seaweed farming, often depicted as a sustainable form of aquaculture, had short- and long-term effects on seagrass growth and abundance that cascaded up through the food web to the level of fishery catches. The coastal fishery, a major subsistence activity in the region, can by removing urchin predators indirectly increase densities of the sea urchin Tripneustes gratilla, which has overgrazed seagrasses in several areas. A study using simulated grazing showed that high magnitude leaf removal – typical of grazing urchins – affected seagrasses more than low magnitude removal, typical of fish grazing. Different responses in two co-occurring seagrass species furthermore indicate that high seagrass diversity in tropical seagrass beds could buffer overgrazing effects in the long run. Finally, a literature synthesis suggests that anthropogenic disturbances could drive shifts in seagrass ecosystems to an array of alternative regimes dominated by other or-ganisms (macroalgae, bivalves, burrowing shrimp, polychaetes, etc.). The formation of novel feedback mechanisms makes these regimes resilient to disturbances like seagrass recovery and transplantation projects. Overall, this suggests that resource use activities linked to seagrasses can have large-scale implications if the scale exceeds critical levels. This emphasizes the need for holistic and adaptive management at the seascape level, specifically involving improved techniques for seaweed farming and fisheries, protection of keystone species, and ecosystem-based management approaches.

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Whitaker, Richard. "The Effects of Commodity Disturbances on Open Economics." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3229.

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This dissertation investigates the effects of commodity disturbances on underlying economies. The analysis conducted in this dissertation comprises of two main themes. The first is investigating which commodity disturbances affect a country's GDP. I examine twenty three OECD countries and nineteen primary commodities in the energy, metal, food and timber sectors using a New Keynesian model that was estimated using the DSGE method. It was found the oil disturbances and to a lesser extend natural gas were the only commodity disturbances that affect a country's GDP. Also, it was found that a country's openness plays an important role in shaping the response to these shocks. The second theme expands on these findings by analyzing the effects of oil and gas disturbances on Trinidad and Tobago by asking (1) How long are the effects from oil and gas disturbances on the economy? (2) How do the long-run effects from oil and gas disturbances differ within the economy? VECM and SVEC methods were used, and the results show that the effects from an oil disturbance are larger in magnitude and duration when compared to a gas disturbance. In addition, the effects of oil and gas disturbances had opposite movements on Trinidad and Tobago's CPI, interest rate, and narrow money velocity, whereas both disturbances were positively correlated in regards to Trinidad and Tobago's output and effective real exchange rate in the long-run.

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Mutl, Jan. "Dynamic panel data models with spatially correlated disturbances." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3729.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.
Thesis research directed by: Economics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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Törnqvist, David. "Statistical fault detection with applications to IMU disturbances /." Linköping : Division of Automatic Control, Department of Electrical engineering, Linköpings universitet, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7094.

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Monsefi, Farid. "Mathematical modeling of electromagnetic disturbances in railway system." Licentiate thesis, Luleå : Luleå University of Technology, 2006. http://epubl.ltu.se/1402-1757/2006/50/LTU-LIC-0650-SE.pdf.

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Eklöf, Johan S. "Anthropogenic disturbances and shifts in tropical seagrass ecosystems /." Stockholm : Department of Systems Ecology, Stockholm University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7285.

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Estes, Becky Lynne Gjerstad Dean H. "Impact of interacting disturbances on longleaf pine communities." Auburn, Ala., 2006. http://repo.lib.auburn.edu/Send%206-15-07/ESTES_BECKY_24.pdf.

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Tanner, Albert Buck. "Study of robotic manipulators subjected to base disturbances." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/105285.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1987.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaves 162-163.
by Albert Buck Tanner.
M.S.

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Motaghedi, Pejmun. "Attenuation of disturbances on an earth observing satellite." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/49614.

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Olsson, Jörgen. "Localized disturbances in a flat plate boundary layer." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/47351.

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Dissertations / Theses on the topic 'Disturbances'

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