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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Octavia

Farber, Michelle Ann 18 April 2019 (has links)
Octavia is a 3D animated story based on experiences of Army divers in the waters of Southeast Asia. I built a strong core set of skills in end-to-end 3D animation throughout my time in the graduate program, and I wanted to incorporate them into a real story for this thesis. The myriad of stories I grew up with inspired the development of this 3D animation due to their uniqueness and their nature as a verbal history. This thesis is based on two objectives: technical excellence in the process of 3D animation, and sharing a previously verbal history to a larger audience. I achieved these goals using a variety of technical animation tools including ZBrush, Maya, Arnold, and Premier. Octavia itself is a modified story from my father's time diving in South Korea. The story details the interactions between an exceptionally curious octopus, Octavia, and a diver, taken from Octavia's perspective. The animation was well received during my defense for its technical difficulty and unique art styles. Octavia will be available online on my website. / Master of Fine Arts / Octavia is a 3D animated story based on experiences of Army divers in the waters of Southeast Asia. I built a strong core set of skills in end-to-end 3D animation throughout my time in the graduate program, and I wanted to incorporate them into a real story for this thesis. The myriad of stories I grew up with inspired the development of this 3D animation due to their uniqueness and their nature as a verbal history. This thesis is based on two objectives: technical excellence in the process of 3D animation, and sharing a previously verbal history to a larger audience. I achieved these goals using a variety of technical animation tools including ZBrush, Maya, Arnold, and Premier. Octavia itself is a modified story from my father’s time diving in South Korea. The story details the interactions between an exceptionally curious octopus, Octavia, and a diver, taken from Octavia’s perspective. The animation was well received during my defense for its technical difficulty and unique art styles. Octavia will be available online on my website.
92

Mathematical programming methods for complex cutting problems / Méthodes de programmation mathématiques pour des problèmes complexes de découpe

Viaud, Quentin 11 December 2018 (has links)
Cette thèse s’intéresse à un problème de bin-packing en deux dimensions avec des défauts sur les bins rencontré dans l’industrie verrière. Les plans de découpe sont guillotine 4-stage exact, les objets à couper sans défauts.Une possible résolution utilise la décomposition de Dantzig-Wolfe puis une génération de colonnes et un branch-and-price. Cela est impossible dans notre cas du fait d’instances de trop grande taille. Nous résolvons d’abord le problème de pricing sans défauts par un algorithme incrémental de labelling basé sur un programme dynamique (DP), représenté par un problème de flot dans un hypergraphe. Notre méthode est générique pour les problèmes de sac-à-dos guillotine mais ne résout pas de larges instances en un temps de calcul raisonnable. Nous résolvons alors le problème de bin-packing sans défauts grâce à un DP et une heuristique de diving. Le DP génère des colonnes “non propres”,ne pouvant pas participer à une solution entière. Nous adaptons le diving pour ce cas sans perte d’efficacité. Nous l’étendons alors au cas avec défauts. Nous réparons d’abord heuristiquement une solution du problème sans défauts. La fixation des colonnes dans le diving sans-défaut est ensuite modifiée pour gérer les défauts. Les résultats industriels valident nos méthodes. / This thesis deals with a two-dimensional bin-packing problem with defects on bins from the glass industry. Cutting patterns have to be exact 4-stage guillotine and items defect-free. A standard way to solve it isto use Dantzig-Wolfe reformulation with column generation and branch-and price.This is impossible in our case due to large instance size. We first study and solve the defect-free pricing problem with an incremental labelling algorithm based on a dynamic program (DP), represented as a flow problem in a hypergraph. Our method is generic for guillotine knapsack problems but fails to solve large instance in a short amount of time. Instead we solve the defect freebin-packing problem with a DP and a diving heuristic. This DP generatesnon-proper columns, cutting patterns that cannot be in an integer solution.We adapt standard diving heuristic to this “non-proper” case while keeping itseffectiveness. We then extend the diving heuristic to deal with defects. Ourfirst proposal heuristically repairs a given defect-free solution. Secondly the defect-free diving heuristic is adjusted to handle defects during column fixing.Our industrial results outline the effectiveness of our methods.
93

The importance of the velocity of the body center of mass in breaststroke

Silva, António José Rocha Martins da January 2001 (has links)
No description available.
94

Unit on integrated sport/recreation activities for physically challenged persons entry level skin and pre-scuba diving training

Strauss, Marceen A. 01 January 1986 (has links)
No description available.
95

Kontím, fáráš, lovíme: Dumpster diving a symbolické hranice mezi čistým a nečistým / Gleaning, trash picking, scavenging: Dumpster diving and symbolic boundaries between clean and unclean

Kubatová, Marie January 2014 (has links)
The author deals with the phenomenon of dumpster diving. Being focused on those divers who are used to dumpster dive not being pressed to it by their financial situation, she concentrates on their definition of purity and their way of dealing with symbolic boundaries of clean and unclean. After summarising social-environmental and social scientific background of the phenomenon in context of the theoretical frame based on Mary Douglas and her book about purity and danger the author presents a qualitative analysis of participant observation and in- depth interviews with informants who dumpster dive voluntarily. Based on quantitatively and representatively tested public opinion on dumpster diving she points both the colourful composition of dumpster divers' motives and ideological believes and their reflection and norm- based boundaries categorization that is connected to food they are used to eat. In connection with informants' conception of food value the author argues that through inspiring power of the first dumpster diving experience informants' understanding and dealing with those boundaries have changed. Nevertheless, she stresses that despite being convinced their way of consumption is right and thus pure the informants tend to apply and present themselves by pattern of conduct that...
96

Investigating the surfacing and diving behaviour and availability of long-finned pilot whales and quantifying the effects of anthropogenic sound on density and strandings of cetaceans in the northeast Atlantic

Jewell, Rebecca January 2014 (has links)
The size and trend of a population is fundamental to the assessment of its conservation status, yet cetacean abundance data are often biased and lack statistical power to detect trends. As a result, the conservation status of many species is unknown and the population-level effects of conservation pressures such as anthropogenic sound cannot be quantified. Failing to account for cetaceans that are unavailable for detection at the surface during abundance surveys will negatively bias estimates of abundance. Analysis of time-depth data revealed that pilot whale dive and surface interval durations, and availability for detection, varied with time of day, but this bias was accurately estimated using the mean dive and surface interval durations. A global analysis of cetacean density estimates compiled from multiple line-transect surveys incorporated covariates describing availability bias, and other sources of variability, to facilitate the detection of underlying temporal trends. Decadal global trends in cetacean density were detected for four species, while significant yearly ocean-scale trends were detected for six families. Exploratory analysis of data compiled from line-transect surveys found some evidence that trends in the density of minke whales and sperm whales in the northeast Atlantic varied between areas with and without seismic survey effort. However, there were insufficient data to clearly identify chronic exposure to anthropogenic sound from seismic surveys as a driver of population change. Analysis of strandings data from the UK and Ireland identified some evidence that harbour porpoise and sperm whale stranding rates were related to seismic survey effort and wind farm construction, but the results were not conclusive. Large-scale cetacean surveys provide valuable information on the density and spatial and temporal distribution of cetaceans that is vital for monitoring populations, but these surveys cannot replace dedicated studies of the population-level effects of sound on cetaceans.
97

Agrégation plaquettaire induite par le phénomène bullaire lors de la décompression / Bubble-induced platelet agregation during decompression

Pontier, Jean-Michel 30 November 2010 (has links)
Si le phénomène bullaire reste le primum movens à l’origine de l’obstruction vasculaire lors de la décompression, les plaquettes sanguines jouent un rôle déterminant dans la physiopathologie de l’accident de décompression (ADD). L’objectif de ces travaux était d’étudier les mécanismes à l’origine de cette agrégation plaquettaire induit par le phénomène bullaire. La première étape a permis de valider un modèle animal d’ADD chez le rat et de confirmer que le degré d’agrégation constituait un indice fiable de sévérité de l’ADD. La seconde a eu pour but d’étudier différents marqueurs spécifiques de l’activation plaquettaire. La troisième étape a étudié les effets de différents anti-agrégants plaquettaires administrés avant l’exposition. Les résultats confirment que le clopidogrel, un inhibiteur spécifique des récepteurs à l’ADP, a un effet protecteur sur le risque de survenue et la sévérité des ADD en réduisant l’importance de l’agrégation plaquettaire. Ces résultats sont en faveur d’un mécanisme d’agrégation ADP-dépendant conséquence des interactions entre les plaquettes et les bulles circulantes. La génération de thrombine, un autre puissant agoniste plaquettaire, interviendrait dans la genèse d’un état pro-thrombotique loco-régional conséquence des lésions induites par le passage des bulles au contact de l’endothélium vasculaire. Enfin, les résultats montrent le rôle joué par les micro-particules dans la diffusion à distance de cet état pro-thrombotique. Des études à venir devront confirmer l’intérêt d’une utilisation du clopidogrel dans le traitement de l’ADD ainsi que le rôle de l’oxyde nitric, de la prostacycline PGI2 et du shear-stress dans l’effet protecteur des vibrations et de l’exercice physique sur le risque de survenue de l’ADD en réduisant l’agrégation plaquettaire et en optimisant la cinétique d’élimination des bulles circulantes. / If bubble-induced mechanical obstruction of vessels is the central event during decompression, blood platelets play a key role in the pathogenesis of decompression sickness (DCS). But bubble-induced platelet aggregation (BIPA) mechanisms are unknown. In a previous study, we highlighted a post-dive decrease in platelet count in divers. The aims of this study was therefore to validate an experimental model of DCD in rat to clarify relationship between blood platelet and bubble formation, investigate platelet activation by measuring different platelet markers, and to study the effects of different antithrombotic pre-treatments. First, the results clearly indicate that clopidogrel, a powerful ADP-inhibitor, has a protective effect on decompression risk improving significantly DCS outcome and reducing DCS severity. The results point to the predominant involvement of the ADP release in the BIPA mechanism. Second, we showed the participation of thrombin generation, a powerful platelet agonist, in the thrombotic event. If local BIPA seems to be the direct consequence of bubble-blood component interactions in vascular bed, the regional thrombotic event could be the consequence of bubble-induced vessel wall injury with a key role played by micro-particles in the general extend. Further human studies should be aimed at demonstrating that clopidogrel can offer a benefit as an adjuvant in DCS treatment and the role played by nitric oxyd and prostacyclin in the protective effect of vibrations and physical exercise on DCS risk reducing bubble-induced platelet aggregation
98

Havelock in India as an Emerging SCUBA Diving Destination : Challenges and Opportunities

Yuspeh, Emmy January 2019 (has links)
This qualitative field study is conducted on the Andaman Islands in India and focuses on the sustainable destination development and SCUBA diving tourism. The island in focus, Havelock, is an emerging tourist destination and an international airport is scheduled to open in the Andamans in 2021. The topic is approached through observation and interviews with people involved with the SCUBA diving industry, selected informants, and diving tourists. Different scales that operate with the island’s development - global, national, regional and local - are investigated. Global warming poses a threat to the coral reefs that is the main resource for tourism at the location and the longterm residents’ education in the subject is absent. The communication between state and nation is a problem as laws are passed without participation or awareness from the local community which makes it difficult for businessowners to invest. Furthermore, diver motivation and satisfaction are investigated. The main motivation of beginner level diving tourists from India are not educated in how the underwater world looks like, but are motivated to see what they already know through movies like “Finding Nemo”. The study reveals that a degraded coral reef does not affect diver satisfaction where the divers are not educated in how a healthy reef looks like. The local Marine Protected Area - Rani Jhansi Marine National Park - is in 2019 funded by the government and there are currently no entrance fees for diving tourists. However, this has been proved successful in other destinations. The Marine Protected Area is perceived as positive by the local SCUBA industry, but it is not interacting with its regulation and governing.
99

Resting Oxygen Consumption Rates in Divers Using Diver Propulsion Devices

Smith, Adam J 29 October 2008 (has links)
The Marine Corps Systems Command documented mission requirements that cannot be met by current rebreathers. They need to extend dive times without compromising the stealth and compact design of existing devices. This can be accomplished by reducing the fresh gas flow rate. The current flow rate is adequate to support a diver in heavy work. However, the diver will be utilizing a Diver Propulsion Device (DPD) during a large portion of the mission in question. The assumption, then, is that this portion of the mission will not require "hard work". Thus, a new fresh gas flow rate can be established which is sufficient to sustain a Marine diver using a DPD but is conservative enough to extend the duration of the dive. This experiment was designed for manned testing of the rebreathers in such a way to establish the average oxygen consumption rate for divers using a DPD. Marine divers were fitted with a Divex Shadow Excursion (DSE) rebreather modified with a Draeger C8A PO2 monitor coupled with a Delta P VR3 dive computer. The DSE is a semiclosed-circuit underwater breathing apparatus that provides a constant flow of mixed gas containing oxygen and nitrogen or helium to the diver. The partial pressure of oxygen (PO2) and diver depth were monitored and recorded at ten-second intervals. The Navy Experimental Diving Unit has developed and tested a computational algorithm that uses the PO2 and depth to compute the oxygen consumption rate. Two techniques were employed to estimate the error in this approach: curve fitting and propagation of error. These methods are detailed and the results are presented. They show that the fresh gas flow rate can be safely reduced while the diver is utilizing the DPD, which consequently, will substantially increase the dive time allowed by the device.
100

Water Entry Impact Dynamics of Diving Birds

Sharker, Saberul Islam 01 May 2017 (has links)
Some seabirds (such as Northern Gannets and Brown Boobies) can dive from heights as high as 30 m reaching speeds of up to 24 m/s as they impact the water surface. It is perceived that physical geometry, particularly of the beak, allows them to endure relatively high impact forces that could otherwise kill non-diving birds. Acceleration data from simplified models of diving birds agree with simulated data for one species (Northern Gannet), however, no reliable experimental data with real bird geometries exist for comparison purposes. This study utilizes eleven 3D printed diving birds (five plunge-diving, five surface-diving and one dipper) with embedded accelerometers to measure water-entry impact accelerations for impact velocities ranging between 4.4 - 23.2 m/s. Impact forces for all bird types are found to be comparable under similar impact conditions and well within the safe zone characterized by neck strength as found in recent studies. However, the time each bird requires to reach maximum impact acceleration and its effect represented here by the derivative of acceleration (i.e., jerk), is different based on its beak and head shape. We show that surface diving birds cannot dive at high speeds as the non-dimensional jerk experienced exceeds a safe limit estimated from human impact analysis, whereas those by plunge divers do not.

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