Spelling suggestions: "subject:"anataxis"" "subject:"anâtaxis""
871 |
Turtle Cam: Live Multimedia Interaction For Engaging Potential Visitor Population To Canaveral National SeashoreTortorelli, Brian Alfred 01 January 2012 (has links)
This project expands the outreach of the Canaveral National Seashore to its visitors, potential visitors, and virtual visitors through its goals in conservancy and preservation of its natural resources. This paper is involved with the current iteration of a series of digital media projects, the Sea Turtle Nest Camera, also known as, Turtle Cam. It details how and why this project was designed to be an ongoing initiative to assist in those goals.
|
872 |
Rapprochement: The Necessary Engagement With The Islamic Republic Of IranTello, Roberto 01 January 2008 (has links)
This study examines the decision making process in Washington which led to the current non-existence of political and economic relations between the Islamic Republic of Iran and the United States. The study examines the U.S.-Iran relationship at three levels-of-analysis: the individual, state, and system levels. From a geopolitical perspective, Iran and the United States have often been natural allies that pursued similar policy goals. After 9/11, the U.S. entered Afghanistan and Iraq which further necessitated the reengagement of Tehran. Iranian regional clout would play a vital role in stabilization of Iraq and Afghanistan and without Iran's assistance; peace will not likely be realized in those states. Amongst the most compelling reasons for Washington to engage in meaningful dialogue with Tehran are: terrorism, the war on drugs, the Iranian sponsorship of militant groups, and Tehran's pursuit of a nuclear program. The study concludes that rapprochement should occur in two phases. The first being cooperation in areas of mutual concern such as the war on drugs. The second phase promoting confidence building methods, which would lead to a strategic partnership based on mutual interests.
|
873 |
Vibration-Based Health Monitoring of Rotating Systems with Gyroscopic EffectGavrilovic, Nenad 01 March 2015 (has links) (PDF)
This thesis focuses on the simulation of the gyroscopic effect using the software MSC Adams. A simple shaft-disk system was created and parameter of the sys-tem were changed in order to study the influence of the gyroscopic effect. It was shown that an increasing bearing stiffness reduces the precession motion. Fur-thermore, it was shown that the gyroscopic effect vanishes if the disk of system is placed symmetrically on the shaft, which reduces the system to a Jeffcott-Ro-tor. The second objective of this study was to analyze different defects in a simple fixed axis gear set. In particular, a cracked shaft, a cracked pinion and a chipped pinion as well as a healthy gear system were created and tested in Adams. The contact force between the two gears was monitored and the 2D and 3D frequency spectrum, as well as the Wavelet Transform, were plotted in order to compare the individual defects. It was shown that the Wavelet Transform is a powerful tool, capable of identifying a cracked gear with a non-constant speed. The last part of this study included fault detection with statistical methods as well as with the Sideband Energy Ratio (SER). The time domain signal of the individual faults were used to compare the mean, the standard deviation and the root mean square. Furthermore, the noise profile in the frequency spectrum was tracked with statistical methods using the mean and the standard deviation. It was demonstrated that it is possible to identify a cracked gear, as well as a chipped gear, with statistical methods. However, a cracked shaft could not be identified. The results also show that SER was only capable to identify major defects in a gear system such as a chipped tooth.
|
874 |
The social regulation and genetic and environmental underpinnings of cortisol : a longitudinal genetically-informed studyCantave, Yamiley Christina 08 1900 (has links)
Contexte : Bien qu’il ait été proposé que l’exposition à un faible statut socioéconomique (SSE) familial altère l’activité de l’axe hypothalamo-pituito-surrénalien et sa production de l’hormone cortisol, les résultats actuels sont incohérents et suggèrent la présence de facteurs supplémentaires susceptibles de modifier ces associations. Pourtant, peu d’études à ce jour ont adopté une approche développementale sensible au timing, à la stabilité et aux changements au sein du SSE familial lors de l’étude de l’association liant le SSE au cortisol. En outre, peu de travaux empiriques ont évalué si cette association est non linéaire ou si elle est modulée par le soutien social. Enfin, rares sont les études qui ont examiné dans quelle mesure cette association est affectée par les facteurs génétiques et par les processus gène-environnement, notamment à l’adolescence. Objectifs : Ancré dans une perspective de psychopathologie développementale, l’objectif principal de cette thèse est d’examiner les processus gène-environnement impliqués dans les associations entre le SSE et divers indicateurs de sécrétion cortisolaire mesurés à l’adolescence. Cette thèse a également examiné dans quelle mesure ces associations sont affectées par le timing, la chronicité et les changements au sein du SSE familial et sont atténuées par le soutien social. Méthodes : Les participants proviennent de l’Étude des jumeaux nouveau-nés du Québec, un échantillon populationnel de jumeaux recrutés à la naissance. Le SSE familial a été recueilli au cours de la petite enfance (0-5 ans) et à la mi-adolescence (14 ans). Le soutien social a été rapporté par les jumeaux à l’âge de 14 et de 19 ans. Le cortisol diurne (n=569) a été mesuré à l’âge de 14 ans au réveil, 30 minutes plus tard, l’après-midi et le soir pendant quatre jours non consécutifs. Le cortisol capillaire (n=704) a été mesuré à l’âge de 19 ans. Résultats : Cette thèse est composée de trois articles. Les résultats des deux premiers articles indiquent que l’étiologie génétique du cortisol au réveil et capillaire fluctuent au long du continuum du SSE mesuré à la petite enfance. Les formes que prennent ces interactions gène-environnement sont toutefois distinctes pour ces indicateurs. De plus, nos résultats révèlent la présence d’associations uniques entre le SSE familial mesuré à la mi-adolescence et la plupart des indicateurs cortisolaire, soit suivant une relation linéaire, ou non linéaire. Nous avons également trouvé que l’association liant le SSE au cortisol capillaire n’est pas expliquée par une étiologie génétique commune, mais semble refléter les effets de l’environnement partagé par les jumeaux. Enfin, les résultats du troisième article suggèrent que l’effet synergique du SES familial mesuré à la petite enfance et à la mi-adolescence prédisent la sécrétion cortisolaire. De plus, l’association concomitante entre le SSE et le cortisol au réveil est modulée par le soutien social. Conclusions : Collectivement, ces résultats soulignent l’importance d’adopter une approche développementale et génétiquement informative lors de l’étude de l’association liant l’adversité aux systèmes physiologiques de stress. Un tel examen pourrait contribuer à une meilleure compréhension des mécanismes sous-tendant les disparités socioéconomiques précoces documentées en matière de santé, d’apprentissage et de comportements. / Background: While exposure to lower family socioeconomic status (SES) has been proposed to
induce alterations in hypothalamic-pituitary-adrenal (HPA) axis activity and its production of the
hormone cortisol, existing findings are inconsistent and suggest the presence of additional factors
that may modify these associations. Yet, few of the past studies have taken a developmental
approach sensitive to the timing, stability, and change within family SES when investigating the
association between SES and cortisol secretion. Furthermore, little empirical attention has been
devoted to assessing the possibility that this association might be nonlinear or is modulated by
youth’s perceived availability of social support. Lastly, the extent to which this association is
affected by genetic factors as well as gene-environmental interplays has seldom been investigated,
particularly in adolescence. Objectives: Rooted in a developmental psychopathology perspective,
the present thesis’s main objective is to examine the gene-environment processes implicated in the
associations of family SES with multiple indicators of cortisol secretion during adolescence. This
thesis also investigated to what extent these associations are affected by the timing, chronicity and
change in SES and buffered by perceived social support. Methods: Participants are from the
Québec Newborn Twin Study, a population-based sample of twin pairs recruited at birth. Family
SES was collected in early childhood (ages 0–5) and mid-adolescence (age 14). Perceived social
support was reported by twins at aged 14 and 19. Diurnal cortisol (n=569) was measured at age 14
at awakening, 30 min later, in the afternoon and evening over four non-consecutive days. Hair
cortisol (n=704) was measured at age 19. Results: This thesis is comprised of three articles. The
results of the first two papers indicate that the genetic etiology of adolescence awakening cortisol
and HCC fluctuated along the continuum of early childhood family SES. The patterns of these
gene-environment interactions were, however, distinct for these indicators. Furthermore, our
results pointed to unique associations between mid-adolescence family SES and most of the diurnal
and hair cortisol indicators, either according to a linear or nonlinear function. We also found that
the association linking mid-adolescence family SES to HCC is not explained by a common genetic
etiology but appears to reflect shared environmental effects. Finally, the results of the third paper
revealed that the synergistic effect of early childhood and mid-adolescence SES predicted cortisol
secretion. Moreover, the concomitant association between SES and awakening cortisol was found
to be modulated by mid-adolescence social support. Conclusions: Collectively, these findings
underscore the necessity of espousing a developmental and genetically sensitive approach in
studies investigating the impact of adversity on stress physiological systems. Such investigations
may pave the way to a fuller understanding of the mechanisms underlying the early roots of
socioeconomic disparities in health, learning and behaviours.
|
875 |
Design, Fabrication and Testing of a Novel Dual-Axis Automatic Solar Tracker System Using a Fresnel-Lens Solar ConcentratorAlmara, Laura Mabel 08 1900 (has links)
This thesis project investigates, analyzes, designs, simulates, constructs and tests a dual-axis solar tracker system to track the sun and concentrates the heat of the sunlight, using a Fresnel lens, into a small area, which is above of an evaporator, to increase the temperature of the seawater to convert it into freshwater. The dual-axis solar tracker was designed with the main objectives that the structure was portable, dismountable, lightweight, low cost, corrosion resistant, wires inside pipes, accurate, small size, follow the sun automatically, off-grid (electrical), use green energy (solar powered), and has an empty area right below of the lens. First, a 500 mm diameter flat Fresnel lens was selected and simulated based on an algorithmic method achieved by a previous PhD student at UNT using MATLAB®, to give the optimization lens dimensions. The lens profile was drawn with AutoCAD®, then output profile lens was simulated in COMSOL Multiphysics®. The objective was to provide the high efficiency, optimum and high precision of the focal rays and heat to the receiver of the evaporator. A novel dual-axis solar tracker system was then designed that is portable, dismountable, lightweight and corrosion resistant. The solar tracker tracks the sun in two axis of rotation automatically during the day time, maximizing the angles of inclination on each axis. After testing computer simulations, the dual-axis solar tracker system was constructed and tested. Last, a detailed cost analysis was performed of the entire project. The outcome of this work can be applied for desalination seawater purposes or other any Fresnel lens application that require a focal high temperature directed by dual-axis solar tracker system.
|
876 |
Central Mechanisms Regulating Pituitary-Adrenal Activity in Infant Guinea Pigs (Cavia porcellus) during Exposure to Psychological Stressors: Independent and Combined Effects of Maternal Separation and NoveltyMaken, Deborah Suzanne 11 December 2009 (has links)
No description available.
|
877 |
Differential effects of stress on the immune response to influenza A/PR8 virus infection in miceHunzeker, John T. 19 May 2004 (has links)
No description available.
|
878 |
Mathematical Modeling and Analysis of a Variable Displacement Hydraulic Bent Axis Pump Linked to High Pressure and Low Pressure AccumulatorsAbuhaiba, Mohammad 16 June 2009 (has links)
No description available.
|
879 |
Är frekvensen av bruxism högre hos individer med vaginism?Tholin, Katarina January 2017 (has links)
Syfte: Det saknas kunskap om samband mellan vaginism och bruxism. Syftet med studien var att studera förekomst av orala parafunktioner och bruxism hos kvinnor med vaginism i jämförelse med kvinnor utan vaginism. Studien syftar även till att undersöka eventuella skillnader kring smärta, stress och somatiska besvär mellan grupperna. Metod: En enkätstudie där en modifierad version av DC/TMD axel II, delades ut till patienter som sökt barnmorska. Resultat: Bland de 26 svarande fanns en tendens till ökade dagliga parafunktioner som att pressa tänder under vaken tid, vilket kunde ses i deltagargruppen med vaginism i jämförelse med kontrollgruppen. Smärta som skulle kunna relateras till TMD och parafunktioner var mer frekventa samt mer uttalade i deltagargruppen med vaginism. Deltagargruppen med vaginism hade även en antydan till mer stress, oro samt somatiska besvär.Konklusion: Den viktigaste slutsatsen utifrån utförd studie är att det inte tydligt skiljer sig mellan en grupp individer med vaginism och en kontrollgrupp avseende bruxism. Deltagargruppen med vaginism har en tendens till mer förekommande orala parafunktioner. TMD smärta är mer förekommande i deltagargruppen med vaginism vilket eventuellt kan vara en orsak av ökade parafunktioner. Båda grupperna hade förekomst av psykosociala riskfaktorer för bruxism, dock var de något mer frekventa i experimentgruppen. Det finns ingen tidigare forskning kring sambandet mellan vaginism och bruxism varvid denna studie med endast ett fåtal deltagare skulle kunna ses som en pilotstudie, vilken kan bidra till att öppna upp för interdisciplinär forskning i ämnet. / Aim: There is a lack of knowledge regarding the relationship between vaginismus and bruxism. The purpose of the study was to investigate the occurrence of bruxism and oral parafunctions in women with vaginismus in comparison to women without vaginismus. The study also aimed to investigate possible differences in pain, stress and somatic disorders between the groups.Method: The survey was executed with a modified version of DC/TMD Axis II, and was distributed to patients seeking care from a midwife.Results: Among the 26 respondents, there was a tendency for increased parafunctions, such as clenching teeth during awake time in the vaginismus group of participants. Pain that could be related to TMD and parafunctions were more frequent and more apparent in the group with vaginismus. The group with vaginismus also had a hint of more stress, anxiety and somatic problems.Conclusion: The most important conclusion from the study is that there is no clear difference between a group of individuals with vaginismus and a control group regarding TMD. The group with vaginismus had a tendency of more oral parafunctions. TMD pain is more common in the group with vaginismus, which might be caused by increased parafunctions. Both groups had psychosocial risk factors for bruxism, however, they were somewhat more frequent in the experimental group. There is no previous research on the relationship between vaginismus and bruxism, this study with only a few participants could be seen as a pilot study, which could help open up interdisciplinary research on the subject.
|
880 |
Modeling and Evaluation of Turret Control Systems for Main Battle TanksLyth, Mikael January 2021 (has links)
The aim of the thesis was to implement and compare control methods in a model of a main battle tank. Three controllers were implemented in a two axis gimbal model and their performances were compared. The comparisons were performed using step changes in the reference signal, frequency analysis of an oscillating reference signal and disturbances, and turret mass uncertainties. The results showed that the sliding mode controller had the best performance for both reference changes and disturbance attenuation. The PID controller had a better performance for the change in reference, compared to the model predictive controller, but a significantly worse disturbance attenuation. Due to model approximations, such as assuming ideal engines and noise reduction, the results likely show a better performance than what can be expected if applied on a real main battle tank. Therefore, the results show an upper limit of the stabilization performance of turret and barrel control and should only be used to compare the controllers. / Målet med uppsatsen var att implementera och jämföra reglermetoder för en teoretisk modell av en modern stridsvagn. Tre metoder implementerades i ett tvåaxligt gimbalsystem och deras prestanda utvärderades. Mer specifikt utvärderades regulatorernas respons för en referensändring, en referensstörning och osäkerheter i tornets massa och massfördelning. Utifrån dessa resultat jämfördes sedan reglermetoderna. Resultaten visade att sliding mode regulatorn hade bäst prestanda för både referensändring och referensstörningen när man tittar på frekvensanalys av mät- och processstörningar. PID-regulatorn hade en bättre prestanda än MPC-regulatorn för en referensändring men en sämre respons för en referensstö-rning. På grund av modellförenklingar som till exempel antaganden om ideala motorer och brusreduktion visar resultaten troligen en något bättre prestanda än vad som kan uppnås på en riktigt stridsvagn. Det medför att resultaten visar en övre gräns för vad styrsystemet för en stridsvagns torn- och eldrörsrotation kan uppnå.
|
Page generated in 0.0322 seconds