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The CISPR of IEC in European and the ANSI in American use the model of site attenuation to evaluate and quantify the quality of OATS. The ANSI also uses the concept of Normalized Site Attenuation (NSA) to eliminate the effects brought about by different antennas, which may cause the inaccuracy of site attenuation. To stringently require the quality of OATS, the measured values of NSA have to be compared with the theoretical ones. If their differences are within (+/-)4 dB at all frequencies, the test environment of the OATS can be accepted. At present, the theoretical values of NSA are used as a standard for verifying the OATS in the world. However, many non-ideal factors derived from certain assumptions and simplifications of the NSA may cause the measured NSA to deviate from the theoretical values. To understand the manner and extent of the effects, in this thesis we find out the non-ideal factors by studying the NSA by numerically simulating the effects of each factor on NSA measurement by the method of moment (MoM), and the results are analyzed and discussed. We find that there is a difference of 6 dB on the NSA when the impedance of the receive antenna is mismatched. Meanwhile, we also study the relationship between the conductivity of non-perfect electrical conductor and the ideal value of NSA. We conclude that a ground plane made by metal can be regarded as a PEC one. However, the values of NSA will increase if the conductivity of ground plane is below 1000 S/m. Besides, considering the humid Taiwan climate in particular, we investigate the condition of a thin layer of water covering the ground plane after rain and the results show that the effect of the water plane will decrease the values of NSA. As for the measurement at a distance of 3 m, a deviation of 2 dB at low frequencies arises from the effect of near field for the case of horizontal polarization. Finally as for the non-conducting table in OATS, our results show that the larger values of relative permittivity and conductivity of table result in the larger change of NSA value. The difference can be 3 dB for the case with a wooden table. With results of our research, the effects of non-ideal factors on NSA measurement can be comprehended clearly. The comparison of the differences also can be used as a reference for the modification of the NSA measurement in the future.

The problem of this study was to assess and compare selected student and environmental variables in seven open-area elementary schools carefully matched with seven traditionally-constructed elementary schools on eight different criteria. The hypotheses were formulated to carry out the following four purposes of the study: 1. To determine the differences between the achievement test scores in reading, language, and mathematics of students attending open-area elementary schools and scores of similar students attending traditionally-constructed elementary schools, as measured by the California Achievement Test and the Comprehensive Tests of Basic Skills administered in grades one, two, and three. 2. To determine if there was greater individualization of instruction in open-area elementary schools as measured by the Individualization of Instruction Inventory. 3. To determine if students attending open-area elementary schools evidenced a greater number of positive actions toward school, as indicated by attendance, number of acts of vandalism, and number of suspensions from school shown in official records of the school district.

Submitted by Rosivalda Pereira (mrs.pereira@ufma.br) on 2017-06-19T18:11:03Z No. of bitstreams: 1 DanielBritoOliveira.pdf: 1113712 bytes, checksum: 1f754d1e3daa67a9a1459e26284f82ca (MD5) / Made available in DSpace on 2017-06-19T18:11:03Z (GMT). No. of bitstreams: 1 DanielBritoOliveira.pdf: 1113712 bytes, checksum: 1f754d1e3daa67a9a1459e26284f82ca (MD5) Previous issue date: 2010-07-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPQ) / Urbanization brings many consequences such as fragmentation and degradation of the remaining forest fragments. Degradation in these fragments can negatively affect the forest species, but favor their use by open area species. Thus we aimed to investigate if tadpoles of open area species are developing, together with those of forest species, in water bodies located in forest fragments in Sao Luis Island, MA, Brazil. For this we collected tadpoles in 32 pools with varied characteristics divided into three different types of environment (open area, outer edge of the forest, and forest interior), during the years 2008 and 2009. We recorded 20 species in five families (Bufonidae, Hylidae, Leptodactylidae, Leiuperidae, Microhylidae). The environmental variables accounted for much of the variation in the abundance of tadpoles, and the percentage of vegetation in the pool, the vegetation height in the forest edge, the distance to the forest, and the depth of the pool showed significative effects. Tadpoles of open area species occured in water bodies located in the forest interior. The increased presence of generalist species, and the reproductive success of open area species in the forests indicate that these areas are impacted. / A urbanização traz diversas conseqüências como a fragmentação e a degradação dos remanescentes florestais. A degradação nesses fragmentos pode afetar negativamente as espécies de mata, mas favorecer a sua utilização por espécies de áreas abertas. Assim, objetivamos investigar se girinos de espécies de áreas abertas estão se desenvolvendo, junto com os de espécies de mata, nos corpos d’água localizados em fragmentos de mata na ilha de São Luis, MA, Brasil. Para isso coletamos girinos em 32 poças de características variadas distribuídas em três tipos de ambiente (área aberta, borda externa de mata e interior de mata), durante os anos de 2008 e 2009. Registramos 20 espécies distribuídas em 5 famílias (Bufonidae, Hylidae, Leptodactylidae, Leiuperidae, Microhylidae). As variáveis ambientais que responderam por grande parte da variação nas abundâncias de girinos foram: porcentagem de vegetação no corpo d’água, a altura da vegetação na borda da mata, a distancia para a mata e a profundidade do corpo d’água. Os girinos de espécies de área aberta ocorreram nos corpos d’água localizados na mata. Além disso a maior presença de espécies generalistas e o sucesso reprodutivo das espécies de área aberta no interior das matas indicaram que estas áreas estão impactadas.

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Made available in DSpace on 2014-07-29T16:21:18Z (GMT). No. of bitstreams: 1 Dissertacao Fernando Landa Sobral.pdf: 687284 bytes, checksum: 9d1a927bc9b256832a9a05b06ad62d7e (MD5) Previous issue date: 2011-05-26 / Communities are assemblages of co-occurring species that potentially interact with each other. They are the result not only of a series of ecological processes or "assembly rules", but also of past and ongoing evolutionary processes. In recent years, the assembly rules have received increased attention from ecologists and two different processes have been explored: environmental filtering and limiting similarity. As the processes involved in the formation of the assemblages appear to vary in a manner dependent on scale, it is expected that such assembly rules have different effects over different spatial scales. Understanding this relationship between ecological processes and spatial scales in which they act has been a great challenge among scholars. In this context, the incorporation of phylogenetic and functional data to diversity classical approaches have established the basis for an emerging area of research in community ecology, promoting the development of many tools to detect the underlying structure of the assemblages and, therefore, to infer the processes assembly responsible for the formation of the assemblages. Here, we demonstrate how the use of different measures of phylogenetic and functional diversity along with the use of different null models can be a promising approach in solving paradigms still poorly understood, discussing how such methods can increase the predictive power of this growing area of research. / As comunidades são assembleias de espécies co-ocorrentes que interagem potencialmente umas com as outras. Elas são resultado não apenas de uma série de processos ecológicos ou regras de montagem , mas também de processos evolutivos passados e contínuos. Nos últimos anos, as regras de montagem têm recebido maior atenção dos ecólogos e dois processos diferentes têm sido explorados: os filtros ambientais e a similaridade limitante. Como os processos envolvidos na formação das assembleias parecem variar de uma forma dependente de escala, espera-se que tais regras de montagem tenham diferentes efeitos ao longo de diferentes escalas espaciais. Compreender essa relação entre os processos ecológicos e as escalas espaciais nas quais eles atuam tem sido um grande desafio entre os estudiosos. Nesse contexto, a incorporação de dados filogenéticos e funcionais às abordagens clássicas de diversidade tem estabelecido a base de uma emergente área de pesquisa em ecologia de comunidades, impulsionando o desenvolvimento de muitas ferramentas para detectar a subjacente estrutura das assembleias e, portanto, inferir os processos de montagem responsáveis pela formação das assembleias. Aqui, demonstramos como a utilização de diferentes medidas de diversidade filogenética e funcional juntamente com o uso de diferentes modelos nulos pode ser uma abordagem promissora na solução de paradigmas ainda pouco compreendidos, discutindo como tais métodos podem aumentar o poder preditivo dessa crescente área de pesquisa.

Made available in DSpace on 2014-12-17T15:37:13Z (GMT). No. of bitstreams: 1 MariliaASB_DISSERT.pdf: 1394968 bytes, checksum: b076e332a2c3f4b9375156425fad6f0f (MD5) Previous issue date: 2012-05-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Bats correspond to 20% of the extant mammal species and, with a few exceptions, use echolocation, a spacial orientation system based on emission and analysis of echoes from sound waves, generally ultrasounds. Echolocation was discovered in the 1940 s and since the 1970 s ultrasound detectors have been commercially available, allowing the investigation of several aspects of the natural history and ecology of bats. Passive acoustic monitoring has been frequently used in habitat use studies, predominantly in North America and Europe, by comparing the number of bat passes between different habitat types. This dissertation presents the first evaluation of the spacial and seasonal variation patterns in the activity of insectivorous bats in the Brazilian biome Pampa, in the state of Rio Grande do Sul. Since bat activity can vary according to habitat type, time of year and climatic conditions, the following hypotheses were tested: 1. bat activity varies between different types of habitat; 2. bat activity varies seasonally; 3. bat activity is influenced by temperature, humidity and wind speed. The acoustic samples were taken along fixed transects of 1500 meters, which were monitored monthly from April 2009 to March 2010. Five habitat types were sampled: eucalypts, stream, riparian forest, wetland and grassland. In each sample, the number of bat passes was obtained by using an ultrasound detector Pettersson D230. A total of 1183 bat passes were registered. Greater bat activity levels was observed along large eucalypts (1.93 bat passes/3min) and along a stream (1.61 bat passes/3 min). A riparian forest (0.94 bat passes/3 min) and a wetland area (0.61 bat passes/3 min) exhibited statistically equal levels of activity. Bat passes were fewer in grassland areas (0,16 bat passes/3 min). Bat activity was not correlated with abiotic factors. However, bat activity was significantly low in the colder season, winter, and was similar in autumn, spring and summer. The observed preference for vegetation borders and water courses agrees with reports from other countries and is attributed predominantly to the high prey abundance in these types of environments. Additionally, low activity in the winter is probably a response to the reduced availability of insects, and to lower temperatures. Our results indicate which areas of arboreal vegetation and water courses should be priorities for the conservation of bats and that alterations of these habitat types might negatively influence bat activity in the region / Os morcegos correspondem a 20% dos mam?feros atuais e, com poucas exce??es, apresentam ecolocaliza??o, um sistema de orienta??o espacial a partir da emiss?o e an?lise de ecos de ondas sonoras, geralmente ultrassons. A ecolocaliza??o foi descoberta na d?cada de 1940 e a partir de 1970 detectores de ultrassons tornaram-se comercialmente dispon?veis, permitindo a investiga??o de diversos aspectos sobre hist?ria natural e ecologia de morcegos. Monitoramentos ac?sticos passivos tem sido frequentemente utilizados em estudos de uso de h?bitat, principalmente na Am?rica do Norte e Europa, comparando-se diferentes locais quanto ao n?mero de vezes em que morcegos s?o detectados. A presente disserta??o apresenta a primeira avalia??o de padr?es espaciais e sazonais na atividade de quir?pteros inset?voros do Brasil, realizada no bioma Pampa, Estado do Rio Grande do Sul. Uma vez que a atividade de morcegos pode variar de acordo com o h?bitat, o per?odo do ano e condi??es clim?ticas, foram testadas as seguintes hip?teses: 1. a atividade de morcegos ? heterog?nea entre diferentes tipos de h?bitat; 2. a atividade apresenta varia??es sazonais; 3. a atividade ? influenciada pela temperatura, umidade e velocidade do vento. As amostragens ac?sticas foram realizadas em transectos fixos de 1500 metros, monitorados mensalmente de abril de 2009 a mar?o de 2010. Os transectos abrangeram cinco tipos de h?bitat: Eucaliptos, Mata Ciliar, Banhado, Canal e Campo. Em cada amostragem, foram obtidos o n?mero de registros de atividade com um detector de ultrassons Pettersson D230. No total, foram obtidos 1183 registros de atividade, sendo que os maiores n?veis de atividade de quir?pteros foram observados em ?rea de ?rvores de eucaliptos de grande porte (1,93 registros/3 min) e de um canal (1,61 registros/3 min). Em segundo lugar, a borda de uma mata ciliar (0,94 registros/3 min) e a margem de um banhado (0,61 registros/3 min) apresentaram n?veis estatisticamente equivalentes de atividade. As ?reas de campo foram menos utilizadas. A atividade de quir?pteros n?o apresentou correla??o com os fatores abi?ticos. Por?m, foi significativamente menor na esta??o mais fria, o inverno, e apresentou valores similares no outono, primavera e ver?o. A prefer?ncia por bordas de vegeta??o e cursos d??gua coincide com o documentado para outros pa?ses e ? atribu?da principalmente ? concentra??o de presas nestes tipos de ambiente. Do mesmo modo, a diminui??o da atividade no inverno ? provavelmente uma resposta ? menor disponibilidade de insetos, al?m das baixas temperaturas. Nossos dados indicam que ?reas de vegeta??o arb?rea e cursos d??gua s?o priorit?rias para a conserva??o de morcegos e que altera??es nestes tipos de h?bitat tendem a influenciar negativamente a atividade de morcegos na regi?o