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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.
1

A physiological approach to optimal time allocation modelling using the tufted duck, Aythya fuligula

Parkes, Roland January 2002 (has links)
No description available.
2

The Development of Diving Capabilities in Weddell Seal (<i>Leptonychotes Weddellii</i>) Pups Throughout Early Ontogeny

Weitzner, Emma 01 June 2019 (has links) (PDF)
Weddell seals (Leptonychotes weddellii) are among the deepest diving pinnipeds (i.e., seals, sea lions, and walrus) and one of the best studied marine mammals in the world; as such, these seals are considered a model species for the study of diving physiology and behavior. Adult Weddell seal dive physiology is rather comprehensively understood, yet previous research has excluded an examination of pups’ initial independent diving attempts, beginning instead with the diving capabilities of near-weaning individuals at four to five weeks of age. This is beyond the point many pups have attempted their first independent dives; pups begin to enter the water at 8-10 days after birth, with some observed in the water earlier. The aim of this study was to investigate the development of diving capabilities and fine-scale behaviors of Weddell seal pups beginning at one week of age throughout their dependence period. Pups were sampled longitudinally at 1, 3, 5, and 7 weeks of age. Total body oxygen stores (TBO2, mL O2) were calculated as the sum of blood, muscle, and lung oxygen stores for each seal at all time points. Blood samples were collected under sedation, muscle oxygen parameters were interpolated, and lung oxygen content was extrapolated from adult values. Flipper-mounted time-depth recorders were used to collect concurrent dive behavior data. In chapter 1, I hypothesized that diving capability (TBO2) would be more strongly correlated with dive experience than calendar age; to examine this, age, mass, and diving parameters were correlated with oxygen stores. I instead found mass and age were most significantly correlated with individual tissue oxygen stores and TBO2. I predicted diving experience would be an important driver of oxygen storage development due to hypoxia exposure, but pups spent the majority of their time in the water at the surface and had little to no exposure to hypoxia during dependence. Increases in mass may enable early advances in diving ability, and with increased diving capabilities, pups will be able to become successful independent foragers. Later exposure to hypoxia may be the key to the subsequent increases in TBO2 observed in yearlings and juveniles. In chapter 2, I used TDR data to predict when pups would be in the water based on developmental, temporal, and environmental factors including age, weaning status, time of day, and weather parameters. Pups spent the most time in the water and made their deepest, longest, and most frequent dives during the late night and early morning hours. These data indicate pups are following the diving patterns of their mothers, which follow the diurnal vertical migration of their prey. The data also suggest Weddell seal pups most likely prioritize learning to swim and navigate as opposed to practicing foraging while still dependent. It is critical for pups to develop their swimming, navigational, and diving abilities while they are still with their moms to ensure their survival. This study is the first to describe the complete trajectory of the development of diving physiology and behavior in Weddell seal pups throughout dependence. It is important to understand how the internal diving physiology of Weddell seal pups develops because this directly determines their diving capabilities and their ability to forage successfully, which in turn directly correlates with their survival. Pup survival is an indicator of population growth rates, so the development of diving physiology in pups can lend insights into larger population-level trends.
3

Coral Bleaching and Dive Operators in the Caribbean: Perceptions of Environmental Change

Sealey-Baker, Mamie January 2011 (has links)
Dive tourism is a growing and important industry which is often reliant on a high quality natural environment. As dive tourism’s significance grows due to its economic and ecological impacts on many tropical destinations, it is important to understand how this special-interest tourism may be affected by environmental change. Mass coral bleaching episodes, a phenomenon with potentially severe implications for the health of coral reef ecosystems, have been increasing in intensity and frequency over the last three decades. This has begun to affect the enjoyment of visitors and the prosperity of individuals and dive tourism businesses that depend on reefs. Therefore, the purpose of this project is to explore the perceptions, opinions and adaptation strategies of dive operators in the Caribbean regarding coral bleaching and its effects on their business and dive tourism. This study was guided by an exploratory, sequential, mixed methods design and consisted of two phases: phase 1, a semi-structured interview, followed by phase 2, a web-based survey. The interviews for the initial phase were done with seven Tobago dive operators in January 2011 to gain perspectives and insights from local dive operators before the web-based survey was sent out. The themes that emerged from the interviews include: a lack of government action, locals and reefs, bleaching and business, and moving forward. A larger regional web-based survey was chosen for a second phase of the study to test operator opinions across the Caribbean. In total 318 operators were contacted, with 90 completing the survey. The results were varied, but the overall consensus was that coral bleaching is an important issue, but at the present time a lack of reef protection is more important. Into the future the issues of coastal development and climate change become more prominent. Based on the 2010 coral bleaching event, which was projected by NOAA to rival that of the 2005 mass bleaching, the 2010 paled in comparison. The operators said it was not as severe as previous bleaching events and that it in fact did not have any impact on their business.
4

Skall mellan dessa höga hus en dag stiga en sång? : Om DIVE-analysen och rekordårens miljöer som kulturarv

Bergstén, Emil January 2010 (has links)
Syftet med uppsatsen är att diskutera om rekordårens bebyggelse kan med hjälp av en DIVE-analys betraktas som en del av kulturarvet. En kvalitativ metod har använts där observationer och historisk såväl som samtida litteratur varit grunden till empirin. Detta i enlighet med DIVE som undersökningsmetod. En kvalitativ analys med ett etnologiskt perspektiv har sedan gjorts. Uppsatsen utgår ifrån Grundad teori och behandlar således tidigare forskning kring kulturarvet, som begreppets karaktär och kulturarvets värden, i det avslutande kapitlet. Studien har resulterat i en analys av Hagalund i Solna stad, Stockholms län, vilket mynnar ut i ett resultat att Hagalund som en förort från rekordåren är ett kulturarv, dock enbart ur ett kunskapsperspektiv. Ur ett upplevelseperspektiv krävs helt andra metoder än DIVE för att utröna om Hagalund är ett kulturarv. Dessutom diskuteras DIVE-analysens förhållningssätt till kulturarvet och kulturarvet som objektivistiskt eller konstruktivistiskt betingat. Studien väcker flera nya frågeställningar kring kulturarvet och rekordårens bebyggelse.
5

Coral Bleaching and Dive Operators in the Caribbean: Perceptions of Environmental Change

Sealey-Baker, Mamie January 2011 (has links)
Dive tourism is a growing and important industry which is often reliant on a high quality natural environment. As dive tourism’s significance grows due to its economic and ecological impacts on many tropical destinations, it is important to understand how this special-interest tourism may be affected by environmental change. Mass coral bleaching episodes, a phenomenon with potentially severe implications for the health of coral reef ecosystems, have been increasing in intensity and frequency over the last three decades. This has begun to affect the enjoyment of visitors and the prosperity of individuals and dive tourism businesses that depend on reefs. Therefore, the purpose of this project is to explore the perceptions, opinions and adaptation strategies of dive operators in the Caribbean regarding coral bleaching and its effects on their business and dive tourism. This study was guided by an exploratory, sequential, mixed methods design and consisted of two phases: phase 1, a semi-structured interview, followed by phase 2, a web-based survey. The interviews for the initial phase were done with seven Tobago dive operators in January 2011 to gain perspectives and insights from local dive operators before the web-based survey was sent out. The themes that emerged from the interviews include: a lack of government action, locals and reefs, bleaching and business, and moving forward. A larger regional web-based survey was chosen for a second phase of the study to test operator opinions across the Caribbean. In total 318 operators were contacted, with 90 completing the survey. The results were varied, but the overall consensus was that coral bleaching is an important issue, but at the present time a lack of reef protection is more important. Into the future the issues of coastal development and climate change become more prominent. Based on the 2010 coral bleaching event, which was projected by NOAA to rival that of the 2005 mass bleaching, the 2010 paled in comparison. The operators said it was not as severe as previous bleaching events and that it in fact did not have any impact on their business.
6

Analýza intro ponoru a jeho účastníků v potápěčské jámě Aquapalace Praha / Analysis of try scuba and its participants in diving pit Aquapalace Praha

Haloun, Tomáš January 2020 (has links)
Title: Analysis of try scuba and its participants in diving pit Aquapalace Praha Objectives: The main objective of this thesis is to analyze which group of people undergo try scuba according to age, average wage, edukation and residence. Methods: The research group consisted of 60 probands from the age of 10. The questionnaire survey was conducted at the diving pit in Aquapalace Čestlice during winter 2018 and spring 2019 under a supervision of trained and certified diving instructors. The questionnaire was always submitted to the probands after the end of the try scuba. Results: The results of the thesis define a group of participants attending try scuba organized by Divers Direct and show the opportunity to further focus on marketing activities and propose changes that would contribute to greater satisfaction of the participant and hence keeping them in diving courses ending with internationally valid certification. Keywords: intro dive, diving, diving instructor
7

Survivances de la peinture du XIXe siècle dans le cinéma italien des années 1910 : la peinture aux origines du cinéma ?

Gailleurd, Céline 09 December 2011 (has links)
Cette étude centrée sur le cinéma italien propose de décrire les liens prolifiques et complexes qui se sont noués entre la peinture du XIXe siècle, européenne et surtout italienne, et les films italiens allant de 1905 (La Presa di Roma, Alberini) à 1920 (La serpe, Roberti). Du filon historique aux mélodrames des dive, de la figuration enthousiaste de l’Histoire, au lyrisme de la passion amoureuse, un effet pictural hante les images cinématographiques qui portent en elles « le ferment d’un tableau possible » (Eric Rohmer). Il s’agira donc de penser les formes de partage entre cinéma et peinture, suivant l’étude iconographique de motifs (gestes, postures, décors, accessoires) et d’éléments formels (composition, cadre, échelle des plans, montage) ouvrant sur la question des styles, que le cinéma prolonge et altère : néoclassicisme, académisme, orientalisme, préraphaélisme, symbolisme, Art Nouveau. Ces notions d’esthétique permettent un rapprochement entre l’histoire de l’art et l’histoire du cinéma, et ouvrent sur la question de la survivance des images. Au moment où l’on enregistre sa disparition en faveur de l’abstraction, la peinture figurative du XIXe siècle persiste, se prolonge, et survit au cinéma. En retour, le cinéma italien des années 1910 tire une part de sa vitalité d’une matière picturale qui appartient déjà au passé. Cette recherche met ainsi à jour une série de questions permettant à la fois de revisiter un pan de l’histoire du cinéma italien, peu étudié en France, et plus largement de penser la relation du cinéma aux autres arts. / This study centers around Italian cinema and proposes to describe the prolific and complex connections that developed between 19th century painting (European and mostly Italian) and the Italian films from 1905 (La Presa di Roma, Alberini) to 1920 (La Serpe, Roberti). From the historical inspiration to the dive melodramas, from the enthusiastic portrayal of History to the lyricism of passionate love, a pictorial effect haunts these cinematographic images in which can be found « the seed of a possible painting » (Eric Rohmer). Therefore, one needs to reflect on what cinema and painting share, following the iconographical study of figurative (gestures, postures, scenery, props) and formal elements (composition, frame, field size, editing) that lead to the question of the styles that the cinema prolongs and alters : neoclassicism, academism, orientalism, pre-Raphaelitism, symbolism, Art Nouveau. These aesthetic ideas allow for a convergence between the history of art and the history of cinema, which opens the question of the images' survival. At a time when 19th century figurative painting was being replaced by abstract art, it persisted and survived in cinema. In return, Italian cinema of the 1910s drew part of its vitality from pictorial material that already belonged to the past.Thus, this research brings to light a series of questions that allow for both a revisitation of a rarely studied period of the history of Italian cinema and more generally to reflect upon the relationship between cinema and other artforms.
8

Vår tids moderna arv : Arkitektoniska och historiska kvaliteter i rekordårens storskaliga bostadsbebyggelse.

Hallgren Pemer, Ruben, Nilsson, Johan January 2016 (has links)
Med detta arbete vill vi se bortom en generellt ogrundad kritik av rekordårens bebyggelse och istället på djupet försöka förstå de kvaliteter som är sprungna ur den tidens ideal. Rekordåren är en unik epok i svenskt bostadsbyggande, och det är av stort samhällsintresse att försöka förstå hur de storskaliga bostadsområdena fungerar, hur de utformats, förändrats och vilket utgångsläge de finner sig i idag. Genom att betrakta dessa områden som del av vårt gemensamma kulturarv finns det möjlighet att på ett nyanserat sätt hitta värden i dess fysiska struktur. I arbetets inledande del görs en forskningsöversikt, med två separata grenar; den ena går igenom rekordårens storskaliga bostadsbebyggelse och dess karaktärsdrag. Den andra delen går igenom begreppet "kulturarv" och synen på vad "värde" innebär i sammanhanget. Sist redogörs den forskning som diskuterat rekordårens bebyggelse som kulturarv. Den huvudsakliga delen i uppsatsen är två fallstudier, så kallade kulturmiljöanalysmetoder - DIVE respektive SAVE som är framtagna av myndigheter från Sverige, Norge och Danmark med fokus på kulturmiljöfrågor. Analysmetoderna appliceras på fallet Rosengård, som valts ut som representativt för ett storskaligt bostadsområde från rekordåren. Metoderna har tagit in historiska dokument och grafiska material (bilder och illustrationer) för att analysera Rosengårds historiska och arkitektoniska kvaliteter. Analyserna görs utefter tydliga metodiker som beskrivs i DIVE och SAVE. Metoderna resulterar i ett antal rekommendationer och förslag på hur de presenterade kulturvärdena kan hanteras vid framtida exploatering och utveckling, som inte fördärvar kulturarvet. I den avslutande delen svarar vi på frågeställningarna om vilka kvaliteter som kan identifieras i rekordårens storskaliga bostadsbyggande, hur synen mellan olika analysmetoder skiljer sig och sist hur framtida ny bebyggelse kan uppföras inom eller i anslutning till dessa områden med hänsyn till dess karaktäristiska fysiska utformning.
9

Dinâmica longitudinal : efeitos da geometria de suspensão nas mudanças de atitude da massa suspensa e os esforços nos elementos da suspensão / Longitudinal dynamics : effects of the geometry suspension on the sprung mass attitude and the effort on elements suspensions

Barreto, Marco Antonio Zanussi 27 June 2005 (has links)
Este trabalho tem como objetivo estudar a influência da geometria de suspensão do veículo nas atitudes da massa suspensa. Apresenta um confronto entre obras e autores e está segmentada em três partes; onde na primeira parte são definidos os conceitos básicos como dive, squat, lift, anti-dive, anti-squat, anti-lift e equivalente trailing-arm; na segunda parte são apresentadas as limitações e os novos conceitos definidos por R. S. Sharp e na terceira parte é apresentado o modelo dinâmico bidimensional introduzido por Fu-Cheng Wang. Apresenta um modelo virtual em sistema de multi-corpos desenvolvido no programa ADAMS, com todos os subsistemas que compõe um veículo completo. Inova ao trazer como objeto de estudo um veículo de competição (fórmula SAE) que possui como particularidade o sistema de suspensão push-rod. Surpreende com os resultados obtidos, pois, contrariam os conceitos básicos encontrados na maioria dos livros / This work has objective study the influence of suspension geometry on the sprung mass attitudes. It presents a confrontation among works and authors and this segmented in three parts; where in the first part the basic concepts are defined, dive, squat, lift, anti-dive, anti-squat, anti-lift and equivalent trailing-arm; in the second part the limitations are presented and the new concepts are defined for R. S. Sharp and in the third part are presented the bidimensional dynamic model introduced by Fu-Cheng Wang. It presents a virtual model in system of multi-bodies developed in the program ADAMS, with all the subsystems that composes a complete vehicle. It innovates when bringing such object to study one vehicle of competition (formula SAE) that it has a particularity suspension system push-rod. It surprises with results because it’s opposite of the basic concepts which is present in the majority of books
10

Evaluation of the Effects of Hyperbaric Dive Environments on the Autonomic Nervous System Using Principal Dynamic Mode Analysis

Bai, Yan 11 August 2011 (has links)
"As water covers over 75% surface area of the earth, humans have an innate desire to explore the underwater environment for various aims. Physiological responses are induced in humans and animals to adapt to different stresses imposed by the hyperbaric environment. When these stresses become overwhelming, certain hazards can occur to individuals in underwater or in similar hyperbaric environments, and they may include nitrogen narcosis, oxygen toxicity and decompression sickness (DCS). There are evidences showing that the autonomic nervous system (ANS) plays an important role in diving reflex and physiological responses to diving hazards. However, the assessment of the autonomic nervous activity during SCUBA dives and diving-related hazards are mostly absent from the literature. Thus, in order to evaluate the autonomic nervous alterations that may occur during diving, especially during DCS, the following three experiments were performed in this study: the simulated dives of human subjects in a hyperbaric chamber, the SCUBA diving performed in seawater and induced decompression sickness in a swine model. A novel algorithm developed in our lab, principal dynamic mode (PDM) analysis, is applied to the above data. It has been shown that the PDM is able to accurately separate the sympathetic and parasympathetic dynamics of the ANS, and subsequently it is able to obtain a better quantification of the autonomic nervous activity than a current golden-standard approach. Through the study, dominance of the parasympathetic modulation was found in both hyperbaric chamber and SCUBA diving conditions. And more stresses were present in real dives, compared to simulated dives in chamber. In the swine DCS model, we found neurological DCS and cardiopulmonary DCS resulted in different alterations in the ANS. Furthermore, tracking dynamics of the parasympathetic modulations via the PDM method may allow discrimination between cardiopulmonary DCS and neurological DCS, and has potential use as a marker for early diagnosis of cardiopulmonary DCS. "

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