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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.
951

Porovnání zdanění příjmů právnických osob v ČR a ve státech Evropské unie / Comparison of corporate income tax in the Czech Republic and in European Union

MRÁČKOVÁ, Andrea January 2017 (has links)
The study is concerned with corporate income taxes in the European Union and comparison these taxation systems. The theoretical part includes development of the harmonisation of the direct tax in the EU and a common consolidated corporate tax base. The study proceeds with the description of the corporate taxation system of the member states. The practical part is mainly dedicated to analysis of these taxation systems of the member countries. It describes elements of corporate income tax legislative and implicit tax rate and share corporate income tax on taxation mix. The analysis is processed in the computer program STATISTICA. The classify is made by cluster analysis that should find the similar taxation system. In conclusion, there are pointed out differences between member countries and an identification of the effects that cause differences.
952

Uncovering views from the occupy movement : Johannesburg leg

Smith, Sean Michael 12 January 2015 (has links)
This exploratory study set out to uncover views from the Occupy Movement’s Johannesburg leg. The Occupy Movement arose in late 2011, aiming to occupy public space and challenge conventional economics, politics, and governance. Data were collected by means of an online survey amongst 39 ‘core’ members of the group. The study took up a mixed methods approach underpinned by critical realism. Basic descriptive statistics and cross tabulations were used to analyse 6 closed-ended survey items in a quantitative fashion; thereafter, 4 open-ended items were qualitatively examined by delineating responses into discursive themes based on response content and positions taken up by respondents in their claims and statements. Finally, a cluster analysis was performed in order to cluster or profile significant groups that emerged from the data based on demographics, selection of closed-ended items, and quantitatively transformed response content to qualitatively examined open-ended items. It was found that the sample mirrored the demographics present in foreign movements as it was primarily male (61.5%), white (87.2%), highly educated (51.4% holding a bachelor’s degree or higher) and young (74.4% in the 21 to 40 age range). Furthermore, it was found that within a group that stood against various macro-level social systems, confidence in all social institutions was extremely low, in particular for big corporations, national government, and political parties. This sample was highly comparable to a representative South African sample as regards their views on the causes of social division; the factors that were seen as most socially divisive (in descending order) were: (1) socio-economic status; (2) race; (3) politics; (4) cultural differences; (5) language; (6) religion; (7) AIDS/disease. Qualitatively, the first item asked whether or not they believed that their movement lacked focus. Upon analysis it was found that four distinct themes existed in response: (1) duality (those revealing support for the movement but disdain for its processes); (2) aggressive justification (vehement justification and defense of the Occupy stance); (3) denial (lacking full knowledge of Occupy processes but ardently defending them while moving away from the difficult questions); (4) straddling the fence (vague and contradictory positions). Members responded to the question of whether their movement differed from foreign movements by stating that it did, based primarily on local socio-historical, economic, and contemporary issues peculiar to South Africa – these members sought a special place for their movement and acted in contradiction to the global Occupy stances; others said no and based this on appeals to homogeneity of cause, global concerns, and an Occupy solidarity. When asked why they, personally, were motivated to engage with the movement, the sample maintained either: (1) the unfair world argument (a strong theme in which perceived ‘systemic unfairness’ proved motivation enough); (2) socialist argument (a string of socialist-based positions connected to classic socialist disdain for the creation of capital, accruing of personal wealth, estrangement of labourers from produce etc.); (3) personal plight argument (exclusively personal standpoints appealing to individual socio-economic woes). Finally, pressure was placed upon the Occupy protestors to reveal what their ideal, utopian society would look like, given the option. The sample called for: (1) orthodox anarchy (stark calls for 4 absolute anarchy); (2) anarchic socialism (marrying socialism and anarchy – less extreme than anarchy, more equal than capitalism, incorporating multiple freedoms and backed by orthodox socialist rhetoric); (3) advancing through decentralized civil society (no clear ideology, rather providing a special place for civil society with few central power structures; driving forth through family and community); (4) fundamental equality and freedom (emphasis of final desires over process and ideology with a belief that society does not require strict regulation, it rather holds its own ‘homeostatic’ capabilities). The hierarchical cluster analysis for this study found 4 distinct clusters; each cluster was defined by a generally homogeneous set of responses and demographics. Significantly, cluster 3 included 50% of the cases analysed (50% of the sample) and uncovered a common profile (homogeneous demographics, vastly similar stances on sources of social division, similarity in terms of confidence in social institutions, and agreement on the rationale and motivation to be personally involvement in Occupy). Cluster 4 consisted of so-called outliers. / Psychology / M. A.( Psychology with specialisation in Research Consultation)
953

The temporospatial dimension of health in Zimbabwe

Chazireni, Evans 03 1900 (has links)
Inequalities in levels of health between regions within a country are frequently regarded as a problem. Zimbabwe is characterised by poor and unequal conditions of health (both the state of people’s health and health services). The health system of the country shows severe spatial inequalities that are manifested at provincial, district and even local levels. This research therefore examines and analyses the spatial inequalities and temporal variation of health conditions in Zimbabwe. Composite indices were used to determine the people’s state of health in Zimbabwe. Administrative districts were ranked according to the level of people’s state of health. Cluster analysis was also performed to demarcate administrative districts according the level of health service provision. Districts with minimum difference were demarcated in a single cluster. Clusters were delineated using data on patterns of diseases and health and such clusters were used to demarcate the country’s spatial health system according to the Adapted Epidemiological Transition Model. This was used to evaluate the applicability of the model to Zimbabwe. It emerged from the research that generally the country’s health conditions are poor and the health system is characterised by severe spatial inequalities. Some districts are experiencing poor health service provision and serious health challenges and are still in the age of pestilence and famine but others have good health service provision as well as highly developed health conditions and are in the age degenerative diseases of the epidemiological transition model. It further emerged that the country’s health has been evolving with signs of improvement since the 1990s. Recommendations were made regarding possible adjustment to previous strategies and policies used in Zimbabwe, for the development of the health system of the country. New strategies were also recommended for the improvement of the health system of the country. Some proposals are made for further research on the spatial development of health in the country. / Geography / D. Litt et. Phil. (Geography)
954

The identification of criteria for the optimal use of Facebook pages for marketing purposes in South Africa : an exploratory study

Barnard, Sune Mari 04 1900 (has links)
The development of non-traditional communication channels in recent years has progressively created a world more digital, networked and interlaced by a myriad of communication tools than ever before. With Facebook being the most prevalent social network, this study aims to guide local organisations to use Facebook optimally to communicate with their customers. The study strives to incorporate the latest ideas about social media marketing in the relevant literature with the opinions of local social media marketing experts. The generally ineffective use of Facebook as a communication channel by small, inexperienced organisations is seen as a justification for identifying a set of criteria to guide organisations in using Facebook pages as a driver of communication. The empirical phase of the research produced a list of seven guidelines on the optimal use of Facebook pages for marketing purposes, which might assist South African companies in developing their marketing strategies. / Business Management / M. Com. (Business Management)
955

O uso de redes neurais auto-organizáveis na análise da transferência de conhecimentos prosódico em aprendizes brasileiros de língua inglesa / The use of self-organizing artificial neural networks for the analysis of prosodic knowledge in Brazilian learner of English

Silva, Ana Cristina Cunha da January 2010 (has links)
SILVA, Ana Cristina Cunha da. O uso de redes neurais auto-organizáveis na análise da transferência de conhecimentos prosódico em aprendizes brasileiros de língua inglesa. 2010, 201f. Tese (Doutorado em Linguística) – Universidade Federal do Ceará, Departamento de Letras Vernáculas, Programa de Pós-graduação em Linguística, Fortaleza-CE, 2010. / Submitted by nazareno mesquita (nazagon36@yahoo.com.br) on 2012-06-28T13:08:58Z No. of bitstreams: 1 2010_tese_ACCSilva.pdf: 2172197 bytes, checksum: 036ba2cdc331410f0516a0ba2abe520d (MD5) / Approved for entry into archive by Maria Josineide Góis(josineide@ufc.br) on 2013-10-10T13:22:45Z (GMT) No. of bitstreams: 1 2010_tese_ACCSilva.pdf: 2172197 bytes, checksum: 036ba2cdc331410f0516a0ba2abe520d (MD5) / Made available in DSpace on 2013-10-10T13:22:45Z (GMT). No. of bitstreams: 1 2010_tese_ACCSilva.pdf: 2172197 bytes, checksum: 036ba2cdc331410f0516a0ba2abe520d (MD5) Previous issue date: 2010 / The objective of this dissertation was to investigate how the prosodic knowledge is organized in an early stage of L2 acquisition in Brazilian learners of English with the help of a connectionist neural network. The approach proposed in this research is first, to quantify the utterances of L2 learners in the form of LPC coefficients and other linguistic/phonetics features that can represent the phenomenon studied here (Transfer of the prosodic knowledge from Portuguese to English). This process is called speech feature extraction, an important step in the connectionist approach to speech processing. Second, since certain features of the lexical item or sentence produced by each learner are determined, these data are entered into the neural network to analyze the statistical properties (regularities) of the set of speakers as a whole. Third, visualization tools are used to analyze how the network organizes speakers and what information is most relevant to this process of group formation (e.g. proficiency level, a certain characteristic or property of speech, among others). The network is known as Self-Organizing Map (Self-Organizing Map, SOM). The SOM organizes speakers for similarity degree in well-defined groups (clusters). Application of SOM in this context is therefore innovative. The SOM network is implemented in Matlab environment using the SOMtoolbox package, which is a set of programming routines developed by the research group in Finland, also the inventors of the SOM. The simulation results indicate that SOM might be used more frequently to assess the degree of distance that a group of learners is to the group of native speakers. Thus, a neural network might be used as a tool in the context of determining the level of foreign language proficiency. / O objetivo desta tese foi investigar como o conhecimento prosódico está organizado em um estágio inicial de aquisição de L2 em aprendizes brasileiros de inglês com a ajuda de uma rede neural conexionista. A abordagem proposta neste trabalho consiste primeiramente em "quantificar" as elocuções dos aprendizes de L2 na forma de coeficientes LPC e outras características linguísticas/fonéticas que possam representar o fenômeno aqui estudado (Transferência do Conhecimento Prosódico do Português para o inglês). A este processo dá-se o nome de "extração de características" da fala (feature extraction), uma importante etapa na abordagem conexionista do processamento da fala. Em segundo lugar, uma vez determinadas as características do item lexical ou da frase produzida por cada aprendiz, são inseridos esses dados na rede neural a fim de analisar as propriedades (regularidades) estatísticas do conjunto de falantes como um todo. Em terceiro, utiliza-se ferramentas de visualização para analisar como a rede organiza os falantes e quais informações são mais relevantes para este processo de formação de grupos (e.g. nível de proficiência, uma certa característica ou propriedade da fala, entre outros). A rede utilizada é conhecida como Mapa Auto-Organizável (Self-Organizing Map, SOM). A rede SOM organiza os falantes por grau de similaridade em grupos bem definidos (clusters). A aplicação da rede SOM neste contexto é, portanto, inovadora. A rede SOM é implementada no ambiente Matlab usando o pacote Som toolbox, que é um conjunto de rotinas de programação desenvolvidas pelo grupo de pesquisa da Finlândia, também inventores da rede SOM. Os resultados das simulações apontam que a rede SOM pode vir a ser usada mais frequentemente para avaliar o grau de distância a que um grupo de aprendizes está do grupo de falantes nativos. Dessa forma, uma rede neural pode vir a ser aplicada como ferramenta no contexto de determinação de nível de proficiência em língua estrangeira.
956

Análise multivariada da implementação dos princípios de gestão da qualidade da série de normas ISO 9000 / Multivariate analysis of implementation of quality management principles from ISO 9000 series

Corrêa, André Luiz 31 August 2018 (has links)
Submitted by Andre Luiz Correa (andreluizcorrea@outlook.com) on 2018-09-19T14:36:13Z No. of bitstreams: 1 Dissertação_André Luiz Corrêa.pdf: 1701858 bytes, checksum: 65f09c0b53af1e89dac3e1238dd5ec93 (MD5) / Approved for entry into archive by Neli Silvia Pereira null (nelisps@fcav.unesp.br) on 2018-09-19T19:42:04Z (GMT) No. of bitstreams: 1 correa_al_me_jabo.pdf: 1701858 bytes, checksum: 65f09c0b53af1e89dac3e1238dd5ec93 (MD5) / Made available in DSpace on 2018-09-19T19:42:04Z (GMT). No. of bitstreams: 1 correa_al_me_jabo.pdf: 1701858 bytes, checksum: 65f09c0b53af1e89dac3e1238dd5ec93 (MD5) Previous issue date: 2018-08-31 / O objetivo geral desta pesquisa foi identificar em que grau os princípios de gestão da qualidade estão inter-relacionados. O primeiro objetivo específico foi identificar o nível de implementação dos princípios de gestão da qualidade na organização. O segundo objetivo específico foi reduzir o conjunto inicial de vinte e uma variáveis para poucas variáveis que expliquem como esses princípios de gestão estão inter-relacionados. O terceiro objetivo foi direcionar a organização para a implementação de ações de melhoria sobre os princípios de gestão que minimizem esforços e recursos necessários. Foi realizado um estudo de caso em uma organização industrial certificada ISO 9001 envolvida na cadeia de suprimentos sucroenergética. O instrumento de coleta de dados foi elaborado tendo como referência a norma ISO 10014. Inicialmente o questionário foi aplicado para um grupo de doze respondentes de perfis distintos para verificar o nível de dificuldade no entendimento das questões. Foi calculado o coeficiente de Cronbach sendo obtido um valor de ∝=0,94, demonstrando forte consistência interna no questionário. Foram obtidas 98 respostas completas que foram analisadas por meio de técnicas estatísticas descritivas e multivariadas, como a análise de fatores por componentes principais e análise de agrupamentos. Para as análises estatísticas foram utilizados os softwares Excel® 2016 e Statistica® 7.0. Por meio da análise de fatores as vinte e uma variáveis iniciais foram reduzidas a dois fatores, que foram denominados gestão de processos e gestão de pessoas. Foram realizadas análises de agrupamentos por métodos hierárquicos e não-hierárquicos e verificou-se que as variáveis pertencentes a cada grupo são as mesmas variáveis com cargas fatoriais elevadas em cada fator. Conclui-se que que os objetivos da pesquisa foram plenamente alcançados demonstrando a eficácia da aplicação de técnicas multivariadas para compreensão de fenômenos resultantes da ação de variáveis inter-relacionadas. Salienta-se que os resultados da pesquisa não podem ser generalizados para outras organizações, devido a análise específica de um caso. / The general objective of this research was to identify to what degree the principles of quality management are interrelated. The first specific objective was to identify the level of implementation of the principles of quality management in the organization. The second specific objective was to reduce the initial set of twenty-one variables to a few variables that explain how these management principles are interrelated. The third objective was to direct the organization to the implementation of improvement actions on the management principles that minimize the efforts and necessary resources. A case study was carried out in an ISO 9001 certified industrial organization involved in the sugarcane supply chain. The data collection instrument was developed with reference to ISO 10014. Initially the questionnaire was applied to a group of twelve respondents from different profiles to verify the level of difficulty in understanding the issues. The Cronbach coefficient was calculated and a value of α = 0.94 was obtained, showing a strong internal consistency in the questionnaire. A total of 98 responses were obtained, which were analyzed using descriptive and multivariate statistical techniques, such as principal components factor analysis and cluster analysis. For the statistical analysis, the software Excel® 2016 and Statistica® 7.0 were used. Through the factor analysis, the twenty-one initial variables were reduced to two factors, which were called process management and people management. Cluster analyses were performed by hierarchical and non-hierarchical methods and it was verified that the variables belonging to each group are the same variables with high factor loads in each factor. It is concluded that the objectives of the research were fully achieved demonstrating the effectiveness of the application of multivariate techniques to understand phenomena resulting from the action of interrelated variables. It should be noted that the results of the research cannot be generalized to other organizations, due to the specific analysis of a case.
957

Equity perception and communication among Arab expatriate professionals in the Kingdom of Saudi Arabia

Hijazy, Muhammad January 2017 (has links)
The research aims to study how the communication context within the Arab cultures influences the employees' perception of equity and reaction to inequity. Specifically, the study explores how employees from Arab cultural backgrounds communicate with each other within the Saudi working context; and how they collect, interpret and use the different contextual information - from the contexts in which they live and work - in order to make judgements about issues related to the perception of equity and reaction to inequity. In order to study the research topic, a conceptual framework is developed to reconcile between Equity Theory, Social Comparison Theory and Hall's Context Model; and as a base serving the process of designing/choosing the methods of collecting and analysing the data. Three main research questions are developed which are about (i) how the communication context is related to employees' willingness and ability to react to inequity (ii) how the communication context shapes the nature of inequity reactions executed by employees and (iii) how the communication context is related to the way equity is perceived among employees. A modified version of critical realism is adopted to focus on exploring the mechanisms, within the communication context, which influence the perception of equity and reaction to inequity. A combination of retroduction and abduction is developed in a sense that retroduction is used to direct the research toward exploring the structure and mechanisms within the research setting, while abduction is used to draw conclusions about how the phenomena studied in the research are evolving by the structure and mechanisms. A mixed methods approach is adopted in the research. The research includes data from thirty-five semi-structured interviews which are conducted in mainly three Saudi private-sector organisations located in Jeddah with twenty-nine male employees and six male managers of six different Arab nationalities. Template analysis is used to analyse the qualitative interview transcripts and field notes, while cluster analysis is used to group the research participants based on their quantitative responses. The research finds that there are no clear-cut areas separating the activities linked to the perception of equity and reaction to inequity. I also conclude that the perception of equity norms and equity comparison components can sometimes be separate activities. Some factors such as the religious interpretation, face-saving, and contextual norms and powers influence the employees' willingness to react to inequity by altering the way in which those employees perceive equity norms. Here, unwillingness decisions are often made not as a result of personal conviction but as a compromise based on the personal evaluation of the surrounding context, realising the inability of the self to react to such situations in the first place. Thus, it can be concluded that inability to react to inequity can reduce the employees' willingness to react against under-rewarded situations. The process of perceiving equity comparison components is found to be related to the type of reaction adopted to re-establish the equity; this relationship is represented by groups affiliated by a hidden factor or factors, which is more influential than the ethnicity/nationality of the group's members. The research makes a methodological contribution to knowledge by suggesting a new approach to study human relations through the communication context; a conceptual contribution by combining the concepts of equity perception, social comparison and communication context in one conceptual framework; and an empirical contribution by providing a fresh insight to contextual themes in the Saudi working environment.
958

Métodos multivariados para agrupamento de bovinos de raça Hereford em função dos parâmetros de curvas de crescimento / Multivariate methods for grouping Hereford cattle breed against the parameters of growth curves

Luiz Ricardo Nakamura 23 January 2012 (has links)
Após o ajuste individual das 55 vacas estudadas pelo modelo Gompertz difá- sico com estrutura de erros autorregressiva de ordem 1 (totalizando 7 parâmetros), notou-se que apenas 6 vacas tinham problemas nas estimativas de seus parâmetros (não convergentes ou não signicativos), dessa forma continuou-se o trabalho proposto com 49 animais. Com as estimativas de cada um dos parâmetros (variáveis nessa etapa) foi realizada a análise de componentes principais e observação do gráco biplot, sendo possível a constatação de que 2 dos parâmetros do modelo continham informações ambíguas com pelo menos um dos demais parâmetros e estes foram retirados da análise, restando 5 parâmetros para o estudo. A análise de componentes principais foi realizada novamente apenas com os 5 parâmetros restantes e os três primeiros componentes principais (escolhidos pelo critério da percentagem de variância original explicada) foram utilizados como variáveis em um processo de agrupamento hierárquico. Após a realização da análise de agrupamentos, observou-se que 5 grupos homogêneos de animais foram formados, cada um com caraterísticas distintas. Desta forma, foi possível identicar animais que se destacavam, positiva ou negativamente, no que tange ao seu peso assintótico e taxa de crescimento. / After individual adjustment of the 55 cows studied using the diphasic Gompertz model with autoregressive structure of errors (totalizing 7 parameters), it was noted that only 6 cows had problems on estimates of the parameters (not converged or not signicant), then the proposed work continued with 49 animals. With each of the parameters estimates (variables at this stage) was performed a principal component analysis and observation of the biplot, and it was possible to nd that two of the model parameters contained ambiguous information with at least one of the other parameters, then these 2 parameters were removed from the analysis, leaving 5 parameters for the study. The principal component analysis was performed again with only ve remaining parameters and the rst three principal components (chosen by the criterion of percentage of original explained variance) were used as variables in a process of hierarchical clustering. After performing the cluster analysis, we found that ve homogeneous groups of animals were formed, each with distinct characteristics. Thus, it was possible to identify animals that stood out, positively or negatively, in terms of their asymptotic weight and growth rate.
959

PADRÕES ATMOSFÉRICOS ASSOCIADOS A EXTREMOS DE PRECIPITAÇÃO NA PRIMAVERA NO ESTADO DO RIO GRANDE DO SUL / ATMOSPHERIC FEATURES ASSOCIATED WITH EXTREME RAINFALL EVENTS IN SPRING IN THE STATE OF RIO GRANDE DO SUL

Santos, Daniel Caetano 18 September 2012 (has links)
The goal of this work is to define the atmospheric patterns associated with the extreme precipitation events in the Rio Grande do Sul (RS) state in spring. The data used were the rainfall series provided by the Agência Nacional das Águas (ANA, in portugues) and reanalysis data of high resolution of the Climate Forecast System Reanalysis (CFSR) of 00 and 12 UTC. From the data of the ANA, on the RS, six homogeneous regions of precipitation were obtained through of Hierarchical Cluster Analysis technique, which are: the East and North Coast (R1), Southern and South Coast (R2), the West and the border with Uruguay (R3), Northern (R4), Midwest (R5) and Northwest (R6). With the averages series for each homogeneous regions, utilizing the technique of quantis, has located the days that precipitation over each region was equal or superior to the quantile 99%. With data of the CFSR was generated a matrix (NxM) being N the dates of extreme events and M are meteorological fields normalized in grid points, selected in a grid 21x19 on the RS. The fields chosen are: mean sea level pressure, thickness between 500 and 1000hPa, geopotential height at 500, zonal component of wind at 850hPa, meridional component of wind at 850hPa, zonal component of wind at 200hPa, meridional component of wind at 200hPa and specific humidity at 850hPa. Using the Non-Hierarchical Cluster Analysis, over the array, were obtained 5 atmospheric clusters, defined as the patterns. For the Cluster 1 the principal events of extreme precipitation had locating in the regions R2, R3, R5 and R6. In Cluster 2, the events of extreme of precipitation was, principally, over the region R1. In Cluster 3, the events of extreme precipitation ocurred in the coastal regions (R1 and R2), border with Uruguay (R3) and regions wit high topography (R4 and R5). In Cluster 4, the rainfall extremes is widespread over all regions. And in Cluster 5, extreme precipitation ocurred principally in the R2, R3 and R4 regions. The Cluster 3 showed strong features of a front incursion, while the characteristics of a Mesoscale Convective System (MCS) are present in Cluters 1, 4 and 5. Thus, the three major weather systems that cause extreme precipitation in RS, the MCS are the most important and only the Upper-level cut-off low not has been clearly identified, but the Cluster 2 presents some features that may indicate their presence, which are for example, the trough axis on the RS and the formation of a surface cyclone on the coast. / O objetivo desta dissertação é a definição de padrões atmosféricos associados a eventos extremos de precipitação no estado do Rio Grande do Sul (RS), na primavera. Os dados utilizados foram as séries pluviométricas disponibilizada pela Agência Nacional das Águas (ANA) e os dados de reanálise de alta resolução do Climate Forecast System Reanalysis (CFSR) das 00 e 12 UTC. A partir dos dados da ANA, sobre o RS, foram obtidas seis regiões homogêneas de precipitação, por meio da técnica de Análise de Agrupamento hierárquica, que são: o Leste e Litoral Norte (R1), Extremo Sul e Litoral Sul (R2), Oeste e Fronteira com o Uruguai (R3), Extremo Norte (R4), Centro-Oeste (R5) e Noroeste (R6). Com as séries médias para cada uma das regiões homogêneas foram localizados, por meio da técnica dos quantis, os dias em que a precipitação sobre cada região foi igual ou superior ao quantil 99%. Com os dados do CFSR foi gerada uma matriz N x M sendo o N as datas de eventos extremos e o M são dados normalizados, em pontos de grade, dos campos meteorológicos selecionados em uma grade 21x19 sobre o RS. Os campos meteorológicos escolhidos foram: Pressão ao Nível Médio do Mar, Espessura entre 500hPa e 1000hPa, Altura Geopotencial em 500hPa, Componente Zonal do vento em 850hPa, Componente Meridional do vento em 850hPa, Componente Zonal do vento em 200hPa, Componente Meridional do vento em 200hPa e Umidade Específica em 850hPa. Aplicando a Análise de Agrupamento Não-Hierárquica sobre a matriz dos campos meteorológicos foram obtidos 5 agrupamentos atmosféricos, definidos como os padrões atmosféricos. Para o Agrupamento 1 os extremos de precipitação ficaram localizados principalmente sobre as regiões R2, R3, R5 e R6. No Agrupamento 2 o extremo de precipitação ficou principalmente sobre a região R1. No Agrupamento 3 os extremos de precipitação ficaram sobre as regiões litorâneas (R1 e R2), de fronteira com o Uruguai (R3) e de regiões com elevação no relevo (R4 e R5). No Agrupamento 4 os extremos de precipitação ficaram generalizados sobre o todas as regiões e no Agrupamento 5 ocasionaram extremos de precipitação nas regiões R2, R3 e R4. O Agrupamento 3 apresenta fortes características de uma incursão frontal, enquanto que as características de um Sistema Convectivo de Mesoescala (SCM) estão presentes nos Agrupamentos 1, 4 e 5. Assim, dos três principais sistemas meteorológicos que causam precipitação extrema no RS, os SCM são os mais importantes e somente o Vórtice Ciclônico em Altos Níveis não foi claramente identificado, mas o Agrupamento 2 apresenta algumas características que podem indicar a sua presença, que são por exemplo, o eixo do cavado sobre o RS e a formação de um ciclone em superfície sobre o litoral.
960

Estratégias de seleção combinando informação individual e de família utilizando simulação de dados / Selection s strategies combining individual and family information using simulated data

Santos, Lidiane Gomes dos 10 August 2007 (has links)
Made available in DSpace on 2015-03-26T13:55:32Z (GMT). No. of bitstreams: 1 texto completo.pdf: 484099 bytes, checksum: 2183b6947a541e4acdedb364504ccd85 (MD5) Previous issue date: 2007-08-10 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The superior phenotypes selection, in individual or families, is a practice of considerable importance for the improvers , once to obtain improved populations it is necessary to select and matings among or inside of families. This work s aim was to compare the efficiency of some arrangements between the individual selection and the selection among families to get combined selection indexes and soon afterwards to verify a cluster analysis was capable to detect different groups. Through the program GENESYS, it was simulated four genomes, each one considering only one characteristic, varying to each other just in value of heritability; then, we have two characteristics of low heritability (0,20 and 0,10), one of medium heritability (0,40) and one with high heritability (0,60). Using those genomes, bases populations of 1000 individuals (500 males and 500 females) with a rate endogamic equivalent to zero were simulated. In each base population, it was aleatory selected 10 males and 100 females corresponding, respectively, to 2% and 20% of selection intensity. When these individuals selected couple, it was maintained a control of 10 females for each male and, as a result, it was kept an initial population with 1000 descending, also maintaining a balance of 10 descending for female. For each characteristic selections, different arrangements were done to obtain combined selection s indexes. Thus, the first obtained index considers 100% for individual phenotype (Individual); the second considers 90% for individual phenotype and 10% for average phenotypic of the family (09P+01F); the third considers 70% for individual phenotype and 30% for average phenotypic of the family (07P+03F); the fourth considers 50% for the two values (05P+05F); the fifth considers 30% for individual phenotype and 70% for average phenotypic of the family (03P+07F); the sixth considers 10% for individual phenotype and 90% for average phenotypic of the family (01P+09F) and the seventh index considers 100% for the average phenotypic of the family (Family). The selected individuals' matings were driven at random. A final population of 1000 individuals was totaled. Each selection s strategy was led by 20 consecutive generations with 10 repetitions seeking to minimize the mistakes and effects of the genetic flotation. For a larger clarity in the interpretation of the results, a grouping analysis was accomplished by optimization by the method of Tocher in three intervals of time, with the first five generations, with the first ten generations and with the 20 total generations. The behavior of the selection s strategies for different herdability s values was not the same. As smaller the value of the heritability is, the difference among the averages phenotypics in each generation is bigger and the total earnings in these averages are smaller. The combination of the individual value with the family s average was more efficient for the lowest heritabilities. For these heritabilities, the individual selection or among families did not show to be a good option. The selection just through the individual s phenotypic value can be a good alternative for the characteristic of average herdabilidade and it was the best to the characteristic of high heritabilities. / A seleção de fenótipos superiores, sejam individuais ou famílias, é uma prática de considerável importância para o melhorista , uma vez que a obtenção de populações melhoradas passa pela seleção e acasalamentos entre ou dentro de famílias. O objetivo deste trabalho foi comparar a eficiência de alguns arranjos entre a seleção individual e a seleção entre famílias na obtenção de índices de seleção combinada e em seguida verificar se uma análise de agrupamento foi capaz de detectar grupos distintos. Por meio do programa GENESYS foram simulados quatro genomas, cada um considerando uma única característica, variando entre si apenas no valor da herdabilidade; assim, tem-se duas características de herdabilidade baixa (0,20 e 0,10), uma de herdabilidade média (0,40) e uma com alta herdabilidade (0,60). A partir desses genomas foram simuladas populações bases de 1000 indivíduos (500 machos e 500 fêmeas) com uma taxa endogâmica igual a zero. Em cada população base foram selecionados aleatoriamente 10 machos e 100 fêmeas correspondendo, respectivamente, a uma intensidade de seleção de 2% e 20%. Por meio do acasalamento desses indivíduos selecionados, mantendo o equilíbrio de 10 fêmeas para cada macho, obteve-se uma população inicial com 1000 descendentes, também mantendo um equilíbrio de 10 descendentes por fêmea. Para cada característica foram realizadas seleções com diferentes arranjos para obtenção de índices de seleção combinada. Assim, tem-se o primeiro índice que pondera 100% para o fenótipo individual (Individual); o segundo que considera 90% para fenótipo individual e 10% para média fenotípica da família (09P+01F); o terceiro com 70% para fenótipo individual e 30% para média fenotípica da família (07P+03F); o quarto com 50% para os dois valores (05P+05F); o quinto com 30% para fenótipo individual e 70% para média fenotípica da família (03P+07F); o sexto com 10% para fenótipo individual e 90% para média fenotípica da família (01P+09F) e o sétimo índice que considera 100% para a média fenotípica da família (Família). Os acasalamentos dos indivíduos selecionados foram conduzidos ao acaso. Totalizou-se uma população final de 1000 indivíduos. Cada estratégia de seleção foi conduzida por 20 gerações consecutivas com 10 repetições visando minimizar os erros e efeitos da flutuação genética. Para maior clareza na interpretação dos dados foi realizada análise de agrupamento por otimização pelo método de Tocher em três intervalos de tempo, com as cinco primeiras gerações, com as dez primeiras gerações e com as 20 gerações totais. O comportamento das estratégias de seleção para os diferentes valores de herdabilidade não foram iguais. Quanto menor foi o valor da herdabilidade, maior foi a diferença entre as médias fenotípicas em cada geração e menor foi o ganho total nestas médias. A combinação do valor individual com a média de família foi mais eficiente para as herdabilidades baixas. Para estas herdabilidades, a seleção individual e a entre famílias não se mostraram boa opção. A seleção apenas pelo valor fenotípico individual pode ser boa alternativa para a característica de média herdabilidade e foi a melhor opção para a característica de alta herdabilidade.

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