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Behavioural adjustments of lion (Panthera leo) in response to risk of human-caused mortalityCotterill, Alayne January 2013 (has links)
Fear of predation can have a major impact on the behaviour of prey species. Despite recent codifying of the concept of the ecology of fear, there has been relatively little focus on how these ideas apply to large carnivore species which, although not prey sensu stricto, may experience fear as a result of threats from humans. This thesis argues that large mammalian carnivores are subject to a Landscape of Fear similar to that described for prey species, and will respond behaviourally to fear of human-caused mortality. The idea of a "Landscape of Coexistence" is introduced to denote the perceived risk from humans and associated behavioural responses that can be overlain on spatio-temporally heterogeneous landscapes. Literature on the ecology of fear for large mammalian carnivores and, as there is a dearth of such literature, the current theory on the ecology of fear for other guilds is reviewed, and how this might inform large carnivore behaviour in a Landscape of Coexistence is explored. Behavioural effects of human-caused mortality risk are revealed for lions living in a human dominated landscape (Laikipia County, Kenya), specifically how lions adjust their movement patterns, habitat use and foraging tactics when in proximity to humans. It is argued that these behavioural adjustments represent a trade-off between maximising fitness enhancing activities and minimising the risk of human-caused mortality, thus need to be taken into consideration along with the lethal effects of humans when explaining the density, distribution and behaviour of lions throughout much of their remaining range. Although fear is generic, 'human-caused mortality risk' represents a distinct and very important sub-set of the ecology of fear for the carnivore guild. The existence of a Landscape of Coexistence has implications for understanding their foraging ecology, and ultimately their population dynamics and role in the ecosystem, and is therefore, important for the conservation of large carnivores throughout large parts of their remaining ranges.
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Composição e estrutura vegetacional em diferentes formações na floresta Atlântica, sul de Santa Catarina, BrasilMartins, Rafael January 2010 (has links)
Florestas pluviais tropicais, entre elas a Floresta Atlântica, são formações de elevada diversidade e riqueza o que as torna muito complexas. Elucidar os mecanismos que mantêm esta diversidade constitui o foco das abordagens ecológicas atuais. O objetivo do presente estudo, além de contribuir para o melhor conhecimento florístico-estrutural da Floresta Atlântica, foi o de avaliar as relações entre espécies e o ambiente, a partir da heterogeneidade florística em respostas a gradientes ambientais. O estudo foi conduzido em três formações florestais no sul Catarinense, compreendendo um fragmento de floresta brejosa, e dois de Floresta Ombrófila Densa, uma submontana e outra montana. Foram amostrados indivíduos arbustivo-arbóreos, com altura a partir de 0,20 m. Classes de tamanho foram estabelecidas, consistindo em (1) indivíduos iguais ou maiores a 0,20 m e menores que 1m; (2) maiores que 1 m e menores que 5 cm de DAP (diâmetro à altura do peito); e (3) iguais ou maiores a 5 cm de DAP. A análise de correspondência canônica aplicada à classe 3 mostrou a segregação das comunidades a partir de gradientes indiretos (altitude e topografia), ocasionando variação na disponibilidade de recursos (gradientes diretos) locais. A análise de nichos aplicada às três classes de tamanho demonstrou especialização de nichos por parte das espécies, conforme demonstrado pelo índice médio de marginalidade (OMI). As relações do ambiente com as fases ontogenéticas demonstraram que as espécies tendem a conservar seus nichos e que esta conservação é mais evidenciada no ambiente de sub-bosque, onde as espécies tendem a coexistir com sobreposição de nichos. / Tropical rain forests, including the Atlantic Forest, are made up of high diversity and richness which makes them very complex. Elucidating the mechanisms that maintain this diversity is the focus of current ecological approaches. The aim of this study also contributes to a better understanding of the floristic-structural Atlantic Forest, was to assess the relationships between species and the environment from the floristic heterogeneity in responses to environmental gradients. The study was conducted in three forests in southern Santa Catarina, including a remnant lowland peat forest and submontane rain forest and montane rain forest.We sampled tree species, height from 0.20 m. Size classes were established, consisting of (1) individuals equal to or greater than 0.20 m less than 1m, (2) greater than 1 m in less than 5 cm DBH (diameter at breast height), and (3) equal or larger than 5 cm DBH. A canonical correspondence analysis applied to the class 3 showed the segregation of communities from indirect gradients (altitude and topography), causing variation in the availability of resources (direct gradients) locations. The analysis of niche applied to three size classes demonstrated expertise in niches by species, as demonstrated by the average index of marginality (IMO). Relations on the environment and ontogenetic stages showed that the species tend to retain their niche and that conservation is more evident in the environment of the understory, where species tend to coexist with overlapping niches.
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Ação docente e moralidade : um estudo com educadores porto-alegrensesVebber, Fernanda Cañete January 2009 (has links)
O presente trabalho investigou a compreensão de professores sobre a ação docente para a construção da moralidade, apoiando-se na perspectiva construtivista de Jean Piaget. Consistiu, principalmente, em refletir sobre a ação docente e a responsabilidade de educar moralmente. Realizaram-se entrevistas individuais semi-estruturadas, orientadas pelo método clínico, com dez professores de diferentes áreas de conhecimento e níveis de ensino da Educação Básica. Os resultados gerais da pesquisa mostram que os professores consideram que suas ações em sala de aula são relevantes para o desenvolvimento moral dos alunos e compreendem que há relação entre atitudes de convivência social e a construção da moralidade. / This work has investigated the understanding of teaching activities for the morality construction by teachers, supported on constructivist perspective of Jean Piaget. It mainly consisted of reflections about teaching activities and the responsibility to educate morally. Individual semi-structured interviews were conducted, guided by the clinical method, with ten teachers of different areas of knowledge and levels of Basic Education teaching. The overall results of research show that teachers consider their activities in class relevant for the moral development of students, and understand that there is a relationship between attitudes of social coexistence and the morality construction.
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Ekologické specializace ptáků na základě prostorových patrností v koexistenci / Ecological specializations of birds based on spatial co-existence patternsPetrová, Kristýna January 2018 (has links)
Ecological specialization based on co-existence patterns is new methodology used for niche breadth measurement using co-existing community with occupancy data. It results in generalist-specialist continuum according to value of speciali- zation index. The aim of this thesis was testing index stability at spatial and tem- poral scale, compare this specialization index with other specialization indices and study changes in specialization with time changes in occupancy. Specialization was quantified using data of breeding birds atlases in the Czech Republic and Europe using two selected indices Theta and Simpson. Methodology seems to be sensitive to spatial scale. Instability appears at small scale for birds, stability and correlation between indices increase with gre- ater scale. Problems with using point counts corresponds to their unsuitability encompass birds' habitats, especially for water dependent birds. Correlations be- tween different time periods are stronger at greater spatial scale. Specialization based on co-existence patterns correlates with specialization according to experts' opinions. Results from comparing changes in specialization with changes in occu- pancy suggest, that most of species tend to leave more diverse sites with occupancy decline.
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Análise de coexistência em redes wirelesshartWinter, Jean Michel January 2013 (has links)
Os sistemas de comunicação sem fio vem ganhando cada vez mais espaço no cenário das comunicações digitais. Em relação aos tradicionais sistemas cabeados, as tecnologias de comunicação sem fio evitam a necessidade de infraestruturas de alto custo, tornam a rede mais flexível, trazem facilidades de reconfiguração e a portabilidade para terminais móveis. Com o crescimento e aprimoramento nos usos das redes de automação novas soluções de comunicação estão surgindo entre elas sistemas de comunicação sem fio que possam ser confiáveis e para aplicações em ambientes mais críticos. Em paralelo o espectro de frequência tem sido cada vez mais ocupado devido à grande demanda, especialmente a faixa de espectro não licenciada. A faixa de frequência de 2.4 GHz (ISM), por exemplo, tem sido vastamente explorada e deve ser atualmente a mais utilizada no mundo, especialmente pela aplicação das grandes redes de comunicação como a world wide web. Este trabalho aborda um estudo sobre coexistência do primeiro protocolo certificado para comunicação sem fio aplicado à indústria, o WirelessHART. É apresentada uma visão geral do protocolo, os diferentes mecanismos de coexistência propostos no padrão e ainda um conjunto de ferramentas desenvolvidas para a análise de desempenho do protocolo WirelessHART. Os estudos de caso utilizam os padrões IEEE 802.11g, IEEE 802.15.1 e o próprio WirelessHART, sendo aplicados a análises experimentais estando presentes condições reais de propagação de sinais de rádio frequência, as quais são muitas vezes simplificadas nos tradicionais trabalhos em ambientes simulados. / Wireless communication systems are gaining more space in digital communications area. Compared to traditional wired systems, wireless communication technologies avoid the need for costly infrastructure, making the networks more flexible, improving portability and allowing an easier reconfiguration of mobile terminals. With the growth and improvement in the use of automation networks, new solutions are emerging in the communication systems, including reliable wireless communication for applications in critical environments. In parallel the frequency spectrum has become increasingly busy due to high demand, especially the unlicensed spectrum band. The frequency range of 2.4 GHz (ISM), for example, has been widely explored worldwide, especially by the application of large communication networks such as the world wide web. This work discusses a study on coexistence of the first certified industrial wireless communication protocol, the WirelessHART. It presents an overview of the protocol, the different coexistence mechanisms proposed in the standard and also a set of tools developed for the performance and coexistence analysis of WirelessHART. Case studies assessing the impact of IEEE 802.11g, IEEE 802.15.1 as well as of other WirelessHART networks experimentally are presented, on which real conditions of propagation of radio frequency signals, which are often simplified in traditional work in simulated environments, are evaluated. Obtained results indicated the adequacy of WirelessHart for industrial applications.
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Parti??o de recursos entre carn?voros simp?tricos (Didelphimorphia e Carn?vora) em um arroio de Mata Atl?ntica no sul do BrasilAndrade, Paula Cristina Barros 31 July 2017 (has links)
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Previous issue date: 2017 / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / Investigar as rela??es ecol?gicas entre esp?cies simp?tricas e suas intera??es com o habitat, s?o importantes para a compreens?o dos mecanismos que controlam a estrutura da comunidade ecol?gica. Entretanto, informa??es a respeito dos mecanismos que permitam a coexist?ncia entre mam?feros simp?tricos s?o ainda escassas. Descrevemos no presente estudo, os padr?es de dieta dos carn?voros simp?tricos Chironectes minimus e Lontra longicaudis, analisamos os poss?veis mecanismos de particionamento de recursos entre essas esp?cies, a partir das dimens?es de nicho alimentar, temporal e espacial e discutimos o potencial para intera??es interespec?ficas, como a competi??o e preda??o. Os h?bitos alimentares dos carn?voros foram estudados a partir das an?lises de amostras de fezes coletadas entre novembro de 2008 e fevereiro de 2012, em fragmentos de Mata Atl?ntica no arroio Morungava, localizado no munic?pio de Gravata?, Rio Grande do Sul, Brasil. Foram coletadas 85 amostras de C. minimus e 21 amostras de Lontra longicaudis, distribu?das entre 23 latrinas encontradas ao longo das margens direita e esquerda do arroio. A cu?ca d??gua e a lontra neotropical apresentaram h?bitos alimentares especialistas, por?m, com dietas distintas, especialmente com rela??o as preferencias alimentares e ? frequ?ncia dos itens consumidos, o que provavelmente se reflete no baixo ?ndice de sobreposi??o de nicho tr?fico entre as esp?cies. Chironectes minimus apresentou uma dieta primordialmente carnivora, no entanto, bastante diversificada, consumindo principalmente crust?ceos dec?podos (100%), insetos (69%) e peixes (40%), enquanto L. longicaudis apresentou uma dieta baseada principalmente no consumo de peixes (95%), seguidos por insetos (71%), e anf?bios anuros (67%). Observamos um padr?o de segrega??o espacial e temporal entre a cu?ca d??gua e a lontra neotropical na ?rea de estudo, embora, evid?ncias demonstrem que essas esp?cies coexistem em algum momento, tanto no espa?o quanto no tempo, j? que, registramos a preda??o da cu?ca d??gua pela lontra neotropical. Este ? o primeiro estudo de particionamento de recursos entre C. minimus e L. longicaudis, fornecendo informa??es importantes sobre os h?bitos alimentares destes mam?feros semiaqu?ticos e sobre os mecanismos ecol?gicos respons?veis pela estrutura desta guilda de carn?voros na Mata Atl?ntica. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biologia Animal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Investigate the ecological relationships between sympatric species and their interactions with the habitat are important for understanding the mechanisms that control the structure of ecological communities. However, informations regarding the mechanisms that allow the coexistence among sympatric mammals are still scarce. Here we described the feeding habits of two sympatric carnivores, Chironectes minimus and Lontra longicaudis, analyzed the resource partitioning mechanisms investigating different niche dimensions such as feeding, spatial and temporal niches, and also discussed the potential for interspecific interactions, such as intrespecific competition and predation. The feeding habits were studied from the analysis of fecal samples collected between November 2008 and February 2012, in fragments of Atlantic Forest in the Morungava stream, located in the city of Gravata?, Rio Grande do Sul, Brazil. 85 samples of C. minimus and 21 samples of Lontra longicaudis distributed among 23 latrines found along the right and left banks of the stream were collected, Water opossum and Neotropical otter presented specialized food habits, however, with different diets, especially regarding food preferences and frequency of consumed items, which is probably reflected by the slight trophic niche overlap between species. Chironectes minimus presented a primordial carnivorous diet, however, very diversified, consuming decapod crustaceans (100%), insects (69%) and fishes (40%), while L. longicaudis presented a diet based mainly on fish consumption 95%), followed by insects (71%), and anuran amphibians (67%). We observed a spatial and temporal segregation pattern among the water opossum and the Neotropical otter in the study site, although, evidences show that these species coexist at some time, both in space and time, since we recorded the predation of the water opossum by the Neotropical otter. This is the first study of resource partitioning among C. minimus and L. longicaudis, providing significant information about the feeding habits of these semi-aquatic mammals and about the ecological mechanisms responsible for the structure of this carnivorous guild in Atlantic Forest.
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Ação docente e moralidade : um estudo com educadores porto-alegrensesVebber, Fernanda Cañete January 2009 (has links)
O presente trabalho investigou a compreensão de professores sobre a ação docente para a construção da moralidade, apoiando-se na perspectiva construtivista de Jean Piaget. Consistiu, principalmente, em refletir sobre a ação docente e a responsabilidade de educar moralmente. Realizaram-se entrevistas individuais semi-estruturadas, orientadas pelo método clínico, com dez professores de diferentes áreas de conhecimento e níveis de ensino da Educação Básica. Os resultados gerais da pesquisa mostram que os professores consideram que suas ações em sala de aula são relevantes para o desenvolvimento moral dos alunos e compreendem que há relação entre atitudes de convivência social e a construção da moralidade. / This work has investigated the understanding of teaching activities for the morality construction by teachers, supported on constructivist perspective of Jean Piaget. It mainly consisted of reflections about teaching activities and the responsibility to educate morally. Individual semi-structured interviews were conducted, guided by the clinical method, with ten teachers of different areas of knowledge and levels of Basic Education teaching. The overall results of research show that teachers consider their activities in class relevant for the moral development of students, and understand that there is a relationship between attitudes of social coexistence and the morality construction.
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Composição e estrutura vegetacional em diferentes formações na floresta Atlântica, sul de Santa Catarina, BrasilMartins, Rafael January 2010 (has links)
Florestas pluviais tropicais, entre elas a Floresta Atlântica, são formações de elevada diversidade e riqueza o que as torna muito complexas. Elucidar os mecanismos que mantêm esta diversidade constitui o foco das abordagens ecológicas atuais. O objetivo do presente estudo, além de contribuir para o melhor conhecimento florístico-estrutural da Floresta Atlântica, foi o de avaliar as relações entre espécies e o ambiente, a partir da heterogeneidade florística em respostas a gradientes ambientais. O estudo foi conduzido em três formações florestais no sul Catarinense, compreendendo um fragmento de floresta brejosa, e dois de Floresta Ombrófila Densa, uma submontana e outra montana. Foram amostrados indivíduos arbustivo-arbóreos, com altura a partir de 0,20 m. Classes de tamanho foram estabelecidas, consistindo em (1) indivíduos iguais ou maiores a 0,20 m e menores que 1m; (2) maiores que 1 m e menores que 5 cm de DAP (diâmetro à altura do peito); e (3) iguais ou maiores a 5 cm de DAP. A análise de correspondência canônica aplicada à classe 3 mostrou a segregação das comunidades a partir de gradientes indiretos (altitude e topografia), ocasionando variação na disponibilidade de recursos (gradientes diretos) locais. A análise de nichos aplicada às três classes de tamanho demonstrou especialização de nichos por parte das espécies, conforme demonstrado pelo índice médio de marginalidade (OMI). As relações do ambiente com as fases ontogenéticas demonstraram que as espécies tendem a conservar seus nichos e que esta conservação é mais evidenciada no ambiente de sub-bosque, onde as espécies tendem a coexistir com sobreposição de nichos. / Tropical rain forests, including the Atlantic Forest, are made up of high diversity and richness which makes them very complex. Elucidating the mechanisms that maintain this diversity is the focus of current ecological approaches. The aim of this study also contributes to a better understanding of the floristic-structural Atlantic Forest, was to assess the relationships between species and the environment from the floristic heterogeneity in responses to environmental gradients. The study was conducted in three forests in southern Santa Catarina, including a remnant lowland peat forest and submontane rain forest and montane rain forest.We sampled tree species, height from 0.20 m. Size classes were established, consisting of (1) individuals equal to or greater than 0.20 m less than 1m, (2) greater than 1 m in less than 5 cm DBH (diameter at breast height), and (3) equal or larger than 5 cm DBH. A canonical correspondence analysis applied to the class 3 showed the segregation of communities from indirect gradients (altitude and topography), causing variation in the availability of resources (direct gradients) locations. The analysis of niche applied to three size classes demonstrated expertise in niches by species, as demonstrated by the average index of marginality (IMO). Relations on the environment and ontogenetic stages showed that the species tend to retain their niche and that conservation is more evident in the environment of the understory, where species tend to coexist with overlapping niches.
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Transmit Waveform Design for Coexisting Radar and Communications SystemsJanuary 2016 (has links)
abstract: In recent years, there has been an increased interest in sharing available bandwidth to avoid spectrum congestion. With an ever-increasing number wireless users, it is critical to develop signal processing based spectrum sharing algorithms to achieve cooperative use of the allocated spectrum among multiple systems in order to reduce interference between systems. This work studies the radar and communications systems coexistence problem using two main approaches. The first approach develops methodologies to increase radar target tracking performance under low signal-to-interference-plus-noise ratio (SINR) conditions due to the coexistence of strong communications interference. The second approach jointly optimizes the performance of both systems by co-designing a common transmit waveform.
When concentrating on improving radar tracking performance, a pulsed radar that is tracking a single target coexisting with high powered communications interference is considered. Although the Cramer-Rao lower bound (CRLB) on the covariance of an unbiased estimator of deterministic parameters provides a bound on the estimation mean squared error (MSE), there exists an SINR threshold at which estimator covariance rapidly deviates from the CRLB. After demonstrating that different radar waveforms experience different estimation SINR thresholds using the Barankin bound (BB), a new radar waveform design method is proposed based on predicting the waveform-dependent BB SINR threshold under low SINR operating conditions.
A novel method of predicting the SINR threshold value for maximum likelihood estimation (MLE) is proposed. A relationship is shown to exist between the formulation of the BB kernel and the probability of selecting sidelobes for the MLE. This relationship is demonstrated as an accurate means of threshold prediction for the radar target parameter estimation of frequency, time-delay and angle-of-arrival.
For the co-design radar and communications system problem, the use of a common transmit waveform for a pulse-Doppler radar and a multiuser communications system is proposed. The signaling scheme for each system is selected from a class of waveforms with nonlinear phase function by optimizing the waveform parameters to minimize interference between the two systems and interference among communications users. Using multi-objective optimization, a trade-off in system performance is demonstrated when selecting waveforms that minimize both system interference and tracking MSE. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2016
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Fundamental Limits on Performance for Cooperative Radar-Communications CoexistenceJanuary 2018 (has links)
abstract: Spectral congestion is quickly becoming a problem for the telecommunications sector. In order to alleviate spectral congestion and achieve electromagnetic radio frequency (RF) convergence, communications and radar systems are increasingly encouraged to share bandwidth. In direct opposition to the traditional spectrum sharing approach between radar and communications systems of complete isolation (temporal, spectral or spatial), both systems can be jointly co-designed from the ground up to maximize their joint performance for mutual benefit. In order to properly characterize and understand cooperative spectrum sharing between radar and communications systems, the fundamental limits on performance of a cooperative radar-communications system are investigated. To facilitate this investigation, performance metrics are chosen in this dissertation that allow radar and communications to be compared on the same scale. To that effect, information is chosen as the performance metric and an information theoretic radar performance metric compatible with the communications data rate, the radar estimation rate, is developed. The estimation rate measures the amount of information learned by illuminating a target. With the development of the estimation rate, standard multi-user communications performance bounds are extended with joint radar-communications users to produce bounds on the performance of a joint radar-communications system. System performance for variations of the standard spectrum sharing problem defined in this dissertation are investigated, and inner bounds on performance are extended to account for the effect of continuous radar waveform optimization, multiple radar targets, clutter, phase noise, and radar detection. A detailed interpretation of the estimation rate and a brief discussion on how to use these performance bounds to select an optimal operating point and achieve RF convergence are provided. / Dissertation/Thesis / Doctoral Dissertation Electrical Engineering 2018
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