Master of Science / Department of Electrical and Computer Engineering / Caterina M. Scoglio / Network researchers for a long time have been investigating ways to improve network performance and reliability by devising new protocols, services, and network architectures. For the most part, these innovative ideas are tested through simulations and emulation techniques that though yield credible results; fail to account for realistic Internet measurements values like traffic, capacity, noise, and variable workload, and network failures. Overlay networks, on the other hand have existed for a decade, but they assume the current internet architecture is not suitable for clean-slate network architecture research. Recently, the Global Environment for Network Innovations (GENI) project aims to address this issue by providing an open platform comprising of a suite of highly programmable and shareable network facilities along with its control software. The aim of this report is to introduce GENI’s key architectural concepts, its control frameworks, and how they are used for dynamic resource allocation of computing and networking resources. We mainly discuss about the architectural concepts and design goals of two aggregates, namely the BBN Open Resource Control Architecture of the (BBNORCA) of the ORCA control framework and Great Plains Environment for Network Innovations (GpENI) belonging to the PlanetLab control framework. We then describe the procedure adopted for hardware and software setup of individual aggregates. After giving an overview of the two prototypes, an analysis of the simple experiments that were conducted on each of the aggregates is presented. Based on the study and experimental results, we present a comparative analysis of control framework architectures, their relative merits and demerits, experimentation ease, virtualization technology, and its suitability for a future GENI prototype. We use metrics such as scalability, leasing overhead, oversubscription of resources, and experiment isolation for comparison.

For the majority of social species, group composition is dynamic, and individuals are interconnected in a heterogeneous social network. In this study I investigate the mechanisms underpinning social structure in the endangered southern resident killer whale (Orcinus Orca) population using a long term dataset, and explore the consequences of these. My results demonstrate that resource availability may be an important determinant of social network structure. A significant relationship between the connectivity of the social network and salmon abundance occurred, with a more interconnected network in years of high salmon abundance. As networks are non-random, highly connected individuals may play a key role in population processes such as information and disease transmission. While associations occurred both within and between matrilines, females had a significantly higher number of associates than males, as did older individuals of both sexes. Older males played a more important role in interconnecting the network. The attributes of group leadership were then investigated in matrilines and in individuals. Leadership was not a factor of size or mean age of matriline. However, there was a significant relationship between leadership score and the matriline sex ratio. Individually, females had higher leadership scores than males, and there was a positive correlation between leadership score and age in both sexes. I suggest that the oldest females have the highest 4 leadership scores due to increased ecological knowledge that comes with a prolonged lifespan. Using multi-generational records for two populations of killer whales, I show that both reproductive and post-reproductive mothers increase the survival of offspring, particularly in older male offspring. This is consistent with theoretical predictions, and may explain why female killer-whales have evolved the longest post-reproductive lifespan of all non-human animals. Given the role that individuals of high network centrality can play in population processes, understanding the driving forces behind social network structure is vital when designing effective conservation and management plans.

Submitted by (edna.saturno@ufrpe.br) on 2017-02-23T12:25:14Z No. of bitstreams: 1 Williams Dantas Charles.pdf: 2829415 bytes, checksum: bf5d0ed2319bb047d509bf6837ebad7e (MD5) / Made available in DSpace on 2017-02-23T12:25:14Z (GMT). No. of bitstreams: 1 Williams Dantas Charles.pdf: 2829415 bytes, checksum: bf5d0ed2319bb047d509bf6837ebad7e (MD5) Previous issue date: 2007-02-15 / Since 50`s, industrial fisheries have been damaged by cetaceans in all oceans, with different intensity levels. According to specialists, this behavior is named depredation, which occurs when the animals eat the fishes caught by a fishing gear. Killer whale has been cited as an animal that shows this kind of behavior often, otherwise other species as a false killer whale or sperm whale have been recorded doing fishing gear interactions. After the creation of the On Board Observers Program (PROBORDO) it was possible to cover all tuna fleet working in northeast of Brazil, based on Natal-RN, Cabedelo-PB and Recife-PE ports. The covering was made by board observers that get important information to the fisheries dynamic knowledge made by pelagic long line. Interactions between false killer whales and killer whales are cited as an important scientific subject, in relation to these fisheries type, that the present study pretends to show up. Factors like interactions type, groups’ size, qualitative and quantitative descriptions of depredated fishes and spatial location of the interactions were analyzed. The false killer whale showed greater occurrence on the study area than other species, generally within groups of few individuals, however, there were situations that the group was composed by hundreds of individuals. This species showed food preference about the target species of this fisheries kind, in other words, tuna and swordfishes instead of others catched, but in case of low productivity, they feed with squid used as a bait on the hooks. Killer whales were observed in the Tropical Western Atlantic, interacting with the fisheries. Also, there were accidental catches of the cited cetaceans by the fishing gear, what can bring serious damage to the individuals caughted. / Desde a década de 50, a indústria pesqueira vem sofrendo perdas provocadas por cetáceos, em todos os oceanos, com diferentes níveis de intensidade, num comportamento denominado pelos especialistas como depredação, que ocorre quando esses animais se alimentam do peixe capturado pela arte de pesca. Orcas verdadeiras têm sido citadas como as que exibem esse comportamento com maior freqüência, porém outras espécies como as falsas orcas e cachalotes, são registradas interagindo com a pesca. Com a criação do Programa de Observadores de Bordo (PROBORDO) foi possível a cobertura de toda a frota atuneira arrendada que opera no nordeste, sediada nos portos de Natal-RN, Cabedelo-PB e Recife-PE por observadores de bordo, que coletam informações relevantes para o conhecimento da dinâmica da pesca realizada com espinhel pelágico monofilamento. Dentre os assuntos de grande valor científico cita-se a ocorrência de interações entre as falsas orcas e as orcas verdadeiras, com esse tipo de pescaria, que o presente trabalho pretende apresentar. Fatores como o tipo de interação, tamanho de grupo, descrição quali-quantitativa dos peixes depredados e localização espacial das interações, foram analisados. A falsa orca apresentou maior ocorrência na área de estudo, geralmente em grupos de poucos indivíduos, porém houve situações em que o grupo era composto por centenas de espécimens. Elas demonstraram preferência alimentar pelas espécies-alvo deste tipo de pescaria, ou seja, atuns e espadartes em detrimento da fauna acompanhante, mas no caso de produtividade baixa, também se alimentavam das lulas, utilizadas nos anzóis como isca. Orcas verdadeiras também foram observadas na região do Atlântico oeste tropical, interagindo com a pesca. Também houveram capturas dos referidos cetáceos pelo espinhel, o que pode causar danos sérios aos espécimens capturados.

Advances in computer technology have enabled the collection, digitization and automated processing of huge archives of bioacoustic sound. Many of the tools previ- ously used in bioacoustics work well with small to medium-sized audio collections, but are challenged when processing large collections of tens of terabytes to petabyte size. In this thesis, a system is presented that assists researchers to listen to, view, anno- tate and run advanced audio feature extraction and machine learning algorithms on these audio recordings. This system is designed to scale to petabyte size. In addition, this system allows citizen scientists to participate in the process of annotating these large archives using a casual game metaphor. In this thesis, the use of this system to annotate a large audio archive called the Orchive will be evaluated. The Orchive contains over 20,000 hours of orca vocalizations collected over the course of 30 years, and represents one of the largest continuous collections of bioacoustic recordings in the world. The effectiveness of our semi-automatic approach for deriving knowledge from these recordings will be evaluated and results showing the utility of this system will be shown. / Graduate / 0984 / sness@sness.net

Veículos autônomos são importantes para a execução de missões dos mais variados tipos, reduzindo riscos aos seres humanos e executando as missões de uma maneira mais eficiente. Neste contexto existem os veículos aéreos não tripulados que são cada vez mais utilizados em missões de vigilância, reconhecimento, resgate, entre outras. Uma das características destes veículos é realizar as missões de maneira autônoma, sem a intervenção de operadores humanos. Desta forma, é necessário que existam formas de detectar aproximações perigosas com outras aeronaves e objetos que possam causar risco de colisão e, consequentemente a perda de ativos de alto valor ou até mesmo vidas humanas e, posteriormente realizar o desvio necessário. Neste cenário foi proposto o MOSAIC, um sistema de detecção e desvio de obstáculos utilizando visão monocular para veículos aéreos de pequeno porte. Para isto, foi desenvolvido um método de estimativa da posição tridimensional dos obstáculos a partir de imagens monoculares e propostas melhorias em algoritmos de detecção. A validação do sistema foi obtida por meio de experimentos simulados e reais sobre cada módulo e os resultados obtidos foram promissores, apresentando um erro de apenas 9,75% em ambientes sem restrições e distâncias de até 20 metros. Com isto, os resultados se mostram melhores que os demais algoritmos encontrados no estado da arte em que o erro é menor que 10% apenas em ambientes controlados e distâncias de até 5 metros. / Autonomous vehicles can be used for different kinds of missions reducing risks to human life and being more efficient. In this context, unmanned aerial vehicles play an important role on surveillance, recognition and rescue missions, among others. Due to the mission nature, these vehicles need to perform actions without human intervention, which requires that dangerous approximations to others aerial vehicles or objects to be detected and properly avoided. This leads to the creation of MOSAIC, an obstacle avoidance system based on monocular vision designed to meet the requirements of miniature air vehicles. A novel approach to estimate obstacle three-dimensional position based on monocular vision was developed and some improvements in the detection algorithm were proposed. The system validation was obtained through simulated and real experiments in which each module could be validated. Promising results were obtained showing an error under 9.75% in unconstrained environments and distance up to 20 meters. This results were better than the algorithms and approaches described in the state of the art where errors are under 10% only on constrained environments and distance up to 5 meters.

Veículos autônomos são importantes para a execução de missões dos mais variados tipos, reduzindo riscos aos seres humanos e executando as missões de uma maneira mais eficiente. Neste contexto existem os veículos aéreos não tripulados que são cada vez mais utilizados em missões de vigilância, reconhecimento, resgate, entre outras. Uma das características destes veículos é realizar as missões de maneira autônoma, sem a intervenção de operadores humanos. Desta forma, é necessário que existam formas de detectar aproximações perigosas com outras aeronaves e objetos que possam causar risco de colisão e, consequentemente a perda de ativos de alto valor ou até mesmo vidas humanas e, posteriormente realizar o desvio necessário. Neste cenário foi proposto o MOSAIC, um sistema de detecção e desvio de obstáculos utilizando visão monocular para veículos aéreos de pequeno porte. Para isto, foi desenvolvido um método de estimativa da posição tridimensional dos obstáculos a partir de imagens monoculares e propostas melhorias em algoritmos de detecção. A validação do sistema foi obtida por meio de experimentos simulados e reais sobre cada módulo e os resultados obtidos foram promissores, apresentando um erro de apenas 9,75% em ambientes sem restrições e distâncias de até 20 metros. Com isto, os resultados se mostram melhores que os demais algoritmos encontrados no estado da arte em que o erro é menor que 10% apenas em ambientes controlados e distâncias de até 5 metros. / Autonomous vehicles can be used for different kinds of missions reducing risks to human life and being more efficient. In this context, unmanned aerial vehicles play an important role on surveillance, recognition and rescue missions, among others. Due to the mission nature, these vehicles need to perform actions without human intervention, which requires that dangerous approximations to others aerial vehicles or objects to be detected and properly avoided. This leads to the creation of MOSAIC, an obstacle avoidance system based on monocular vision designed to meet the requirements of miniature air vehicles. A novel approach to estimate obstacle three-dimensional position based on monocular vision was developed and some improvements in the detection algorithm were proposed. The system validation was obtained through simulated and real experiments in which each module could be validated. Promising results were obtained showing an error under 9.75% in unconstrained environments and distance up to 20 meters. This results were better than the algorithms and approaches described in the state of the art where errors are under 10% only on constrained environments and distance up to 5 meters.

During the last deglaciation (ca. 24-10 ka thousand years ago (ka)), the North American Laurentide Ice Sheet (LIS) was a major source of meltwater to the Arctic Ocean, North Atlantic Ocean, and the Gulf of Mexico (GOM), and it is hypothesized that meltwater routing played an important role in regulating Late Quaternary millennial-scale climate variability, via its influence on Atlantic Meridional Overturning Circulation (AMOC). For example, the meltwater routing hypothesis predicts that a rerouting of meltwater from the GOM to the North Atlantic and/or Arctic Oceans resulted in a decrease of North Atlantic Deep Water (NADW) formation and subsequent cooling in the northern North Atlantic region, at the onset of the Younger Dryas (ca. 13 ka). The GOM was an important outlet for meltwater that likely originated from the southern margin of the LIS. Northern GOM sediments document episodic LIS meltwater input via the Mississippi River throughout the last deglaciation, and further study may provide insight to the evolution of LIS deglaciation and the hydrological response of meltwater flux to the marine depositional environment of GOM. Here, a multi-proxy geochemical study, based on marine sediments from Orca Basin, in northern GOM, aims to 1) reconstruct high-resolution records of deglacial (ca. 24-10 ka) LIS melting history to assess linkage between meltwater input to the GOM and deglacial climate change; 2) investigate the relationship between marine-based records of meltwater input and terrestrial evidence for continental deglaciation to reconstruct LIS drainage patterns within the Mississippi River watershed; and 3) reconstruct the redox state of Orca Basin sediments to evaluate the potential role of turbidity flows as a means of meltwater transport into the northern GOM. All data for this study is from core MD02-2550, a 9.09 m long giant box core, recovered from 2248 m water depth from the Orca Basin, approximately 300 km southwest of the modern Mississippi River delta. High sedimentation rates (45 cm/thousand years (kyr)) and 0.5 to 2 cm sampling resolution allow for sub-centennial sampling resolution. An anoxic hypersaline brine lake currently occupies the bottom 200 m of Orca Basin; yet, visible laminations and color changes that suggest episodic suboxic to anoxic sedimentary conditions during deglaciation, possibly related to LIS meltwater input and/or local biologic productivity. In chapter one, paired d18O and Mg/Ca-sea-surface temperature (SST) analyses on two varieties of the surface-dwelling planktic foraminifera Globigerinoides ruber (G. ruber; (white and pink, separately)) are used to reconstruct deglacial changes in GOM seawater d18O (d18Osw). Once corrected for global ice volume, the ice volume-corrected d18Osw (d18Oivc-sw) record is primarily influenced by LIS meltwater. d18Oivc-sw records document negative excursions at ca. 19-18.2, 17.5-16.2, 15.3-14.8, and 13.7-13 ka, interpreted as four LIS melting events, followed by the cessation of meltwater at the onset of the Younger Dryas (12.9 ka). Additionally, LIS melting at ca. 17.5 ka suggests that enhanced seasonality in the North Atlantic produced mild summers sufficient for ice sheet retreat during the Mystery Interval (17.5-14.5 ka) despite extremely cold winters. Because of the inherent difficulties in quantifying meltwater flux using d18Oivc-sw data, foraminiferal (G. ruber) Ba/Ca data are generated in chapter two to assess the influence of LIS meltwater on GOM salinity (a function of meltwater flux) during deglaciation. Ba concentrations in the Mississippi River are elevated relative to GOM seawater and are negatively correlated to sea-surface salinity. Because foraminiferal Ba/Ca (Ba/Caforam) exhibits a predictable relationship to the Ba/Ca of seawater (Ba/Casw), it may be used to calculate changes in salinity arising from deglacial variations in Mississippi River discharge. A complicating factor for Ba/Ca-based salinity interpretations is that Ba concentrations vary spatially throughout the Mississippi River watershed. For example, modern Missouri and Upper Mississippi River Ba concentrations (633 and 436 nM, respectively) are higher than that of the Ohio River (253 nM). Thus, GOM Ba/Ca variability could reflect changes in total Mississippi River input and/or shifts in the dominant region of LIS melting. Applying the modern spatial variability of Ba, we can gain insights into the pattern of ice retreat along the southern margin of the LIS during the last deglaciation. d18Oivc-sw and Ba/Ca results suggest that meltwater, originating from the Great Lakes region, entered the GOM at ca. 19.0 ka and may have contributed to global sea level rise. A melting event at ca. 17.5 ka coincided with Lake Erie Lobe retreat and may have preconditioned the North Atlantic for AMOC instability during the Mystery Interval (ca. 17.5-14.5 ka). Elevated GOM Ba/Ca (ca. 15.6 to 14.0 ka) suggests greater meltwater input from the Ba-rich Missouri and Upper Mississippi River watershed during the second half of the Mystery Interval (ca. 16.1-14.5 ka), when wet climate conditions prevailed in the southwestern United States and Central America. Overall, Ba/Ca and d18Oivc-sw data suggest large variations in the delivery of meltwater to the Mississippi River and GOM during the last deglaciation. In chapter three, a suite of redox sensitive trace metals (Mo, Re, U, Mn) from bulk sediment samples are analyzed to reconstruct the redox state of Orca Basin sediments, from the Last Glacial Maximum through the early Holocene (24-7 ka). Variations in the redox state of Orca Basin sediments during deglaciation may be due to changes in local biologic productivity, sediment transport, and/or regional/global physical oceanography. Laminated sediments enriched with authigenic Mo, Re, and U, suggest suboxic to anoxic conditions coincident with high total organic carbon fluxes and LIS meltwater input at ~17.0 ka. Low authigenic trace element concentrations, high quantities of terrigenous material, and abundant Cretaceous-age nannofossils in a 19-cm homogenous interval indicate a turbidite in Orca Basin at ca. 14.4 ka. This stratigraphic unit correlates with evidence from Pigmy Basin, and the Louisiana Shelf, suggesting increased meltwater flux may reflect LIS contribution to Meltwater pulse 1a (MWP-1a) sea level rise. Trace element records coupled with analyses of Orca Basin sedimentary structures will likely improve understanding of deglacial water column stratification, how meltwater entered the GOM (i.e. as a buoyant cap or at depth via sediment-laden hyperpycnal plumes), and the affects of glacial meltwater on marine biologic productivity.

The objective of this project is to reconstruct a picture of initial Laurentide Ice Sheet retreat at the end of the Last Glacial Maximum (LGM) using geochemical proxies in Gulf of Mexico sediments, and place the reconstruction into global perspective. The project asks two questions. (1) Can a time frame be established for initial retreat of the Laurentide Ice Sheet? (2) If so, how does the timing compare to that of other large ice sheets and mountain glaciers in both hemispheres? Sediment core MD02-2550 from the anoxic Orca Basin offers excellent preservation and a high sediment accumulation rate. Twelve accelerator mass spectrometry 14C dates provide very good age control from 18.36 - 23.88 ka, the transitional period from glacial to deglacial conditions. Paired Mg/Ca and d18O from the planktonic foraminifera Globigerinoides ruber (pink variety) were combined with a matching record from the upper half of the same core from a previous study (Williams et al., 2010), expanding the record to 10.73 - 23.86 ka. Sea surface temperature (SST) derived from Mg/Ca exhibits a mean value of 23.0 ± 0.8°C through the LGM (18.4-23.9 ka), ~3.9°C below the modern summer mean. At 18.4 ka, mean values drop in an anomalous cold snap, exhibiting a mean of 21.7°C that lasted until 17.8 ka. At 17.8 ka, SST begins a recovery warming toward present day conditions. This warming occurs markedly early relative to the onset of the Bølling-Allerød warm period, known best from Greenland ice core records. The d18O of seawater exhibits no sustained shift toward more depleted values that would be consistent with a single major surge of initial meltwater. Instead, d18Osw appears to have been over 1.5 per mil below the modern mean throughout the LGM, persisting through the early deglacial period, and not shifting toward more positive values until well into the Younger Dryas. The corresponding salinity estimates were likewise ~2 psu lower than modern surface waters. Several negative excursions (~1 per mil) during the LGM and deglaciation coincide with millennial-scale retreats of individual lobes along the southern margin of the Laurentide Ice Sheet. These retreats and re-advances have previously been suggested to mirror small short-term excursions in Greenland ice core d18O, that reflects air temperature changes. The consistently depleted d18Osw-ivc values and corresponding salinity estimates through the LGM require a mechanism to create a steady-state lower salinity environment in the northern Gulf of Mexico during the LGM, which would persist as SST changed.

Group living is a social strategy adopted by many species, where individuals can exhibit long-term social affiliation with others, strengthened through cooperative behaviour and often kinship. For highly social mammals, changes in group membership may have significant consequences for the long-term viability and functioning of a population. Detecting significant social events is essential for monitoring the social dynamics of such populations and is crucial to determining the factors underlying these events. Detecting when changes in social organization occur, especially with incomplete data, poses significant analytical challenges. To resolve this issue, I developed and assessed a straightforward, multi-stage and generalizable method with broad utility for ecologists interested in detecting and subsequently investigating causes of changes in social organization. My approach illustrates the frequency and ecological relevance of group fission and fusion events in a population of fish-eating ‘Resident’ killer whales (Orcinus orca). Group fission is a process commonly found in social mammals, yet is poorly described in many taxa, and has never been formally described in killer whales. To address this gap, I provided the first description of matrilineal fission in killer whales, from a threatened but growing Northern Resident killer whale population in which matrilineal fission has been observed for the past three decades. I also undertook the first comprehensive assessment of how killer whale intragroup cohesion is influenced by group structure, demography and resource abundance. Fission in Northern Resident killer whales occurred both along and across maternal lines, where animals dispersed in parallel with their closest maternal kin. I show that fission in this population is driven primarily by population growth and the demographic conditions of groups, particularly those dictating the nutritional requirements of the group. I posit that intragroup food competition is the most likely explanation for group fission in this population, where prey abundance also has ancillary effects. As group fission can have a direct impact on the fitness of group members and the long-term viability of a population, my findings underscore the importance of incorporating studies of sociality into the management of threatened populations of social mammals. / Graduate / 0329 / 0472

Ways of understanding, living, and communicating with non-human species, and more specifically endangered species, have been thought of dualistically and hierarchically in Western cultures. This type of thinking is harmful when examining environmental issues that involve more than just humans, which is arguably all environmental issues. By enforcing a nature/culture dichotomy, humans are seen as separate from nature and therefore they can ethically excuse themselves from dealing with environmental issues that happen "out there" in nature. This thesis explores two manifestations of this nature/culture separation as it continues to threaten wild orca populations in Puget Sound. The first is because of an anthropocentric culture and the second is because of the capitalist socio-economic system. The anthropocentric part of this type of thinking raises humans up on a pedestal, above all non-human species. It gives humans the excuse to only care about issues that affect them directly. The capitalistic part of this type of thinking enforces human's exploitation and commodification of nature. I argue that anthropocentrism and capitalism together create a human/nature relationship that harms nature and benefits humans. This relationship is illustrated by a small population of orcas, called the Southern Resident Killer Whales (SRKW), off the coast of Washington State that are endangered because of human interference. Lack of prey, toxic water pollution, and excessive noise from boats caused them to become endangered, and these issues are produced by Western society's anthropocentric attitudes and capitalistic systems. The SRKW's will go extinct if the environmental destruction of Puget Sound doesn't end and it will only end if the anthropocentric attitudes and capitalistic systems are dismantled.