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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.
201

台灣自行車產業與景氣循環之探討

駱俊文, Chun-Wen Lo January 1900 (has links)
自行車一詞儼然成為綠色環保的代名詞之一,台灣自行車業過去在國際間,被認定為品質粗糙的產品,在經過多年努力的情況下,台灣自行車業不斷的備受肯定,隨著近年全球暖化議題、全球性健康概念、油價飆漲、金融海嘯爆發等,諸多原因造成自行車從不被看好的代步工具,演變到現在成為休閒運動工具的轉變,其中;台灣自行車2008年的金融海嘯中,相較於其他傳統產業,不論是出口產值或是股價不降反漲,大舉逆勢成長,其中巨大(Giant)、美利達(Merida)、愛地雅(Ideal),成車製造商,近年來分別占出口前三大。 所以本研究要探討,金融海嘯爆發的前後,對台灣自行車業帶來的影響,研究資料選定為2000年1月至2013年12月間的巨大股價(9921)、美利達股價(9914)、愛地雅股價(8933)、台灣股價加權指數(TWII)、原油價格、工業生產指數的月資料,共168筆。透過單根檢定檢測資料是否為定態,利用共整合檢定確定是否含有至少一組解,搭配向量誤差修正模型檢測變數間的長短其關係,在利用複迴歸模型檢測。 研究結果顯示,巨大、美利達、愛地雅和台灣加權股價指數具有顯著關係,由於台灣自行車屬於出口導向以及中高價位產品,故全球景氣對台灣自行車業深具影響。其中,巨大和美利達除了ODM外,亦有自有品牌在全球銷售,愛地雅定位專業ODM專業代工廠,前者發展不同市場。 / The word "bicycle" has become one of the pronouns of environmental protection. In the past, Taiwan bicycling industry was treated as low-quality products internationally. With long-time effort, Taiwan bicycling industry was highly appreciated. Recently, global warming issue, cosmopolitan health sense, dramatically increased oil price, the eruption of financial crisis, and many reasons lead the bicycles have not positively evaluated as means of transportation. Now, it becomes the outdoor recreation mean. Comparing Taiwan bicycling industry with other traditional industry, it doesn't fall down but highly increase no matter export value or stock price. The manufacturer of Giant, Merida, and Ideal are the top 3 of export recently. So this study want to explore the things happened before and after the outbreak of the financial crisis that affects bicycle industry in Taiwan, research data for selected between January 2000 and December 2013, relationship between the Giant(9921) shares, Merida (9914) shares, Ideal(8933) shares, TWII, the price of crude oil, industrial production index. Through the Unit Root Test to test whether the data is the steady state or not. By using cointegration test to make sure whether contains at least one group of solutions and vector error correction model to detect the length of the relationship between variables, and using the multiple regression model to test. Results of the research shows that Giant, Merida, Ideal has significant relationship with TWII, because Taiwan bicycle are export-oriented and high price products, so the global boom has profound influence to Taiwan bicycle industry, among them, the Giant and Merida except the ODM, have their own brands in global sales, Ideal professional locate, ODM professional contract, the former develops different markets. / 摘要 I Abstract II 謝辭 III 目錄 IV 圖目錄 VI 表目錄 VII 第一章 緒論 1 第一節 研究動機 1 第二節 研究目的 3 第三節 巨大機械工業股份有限公司簡介 4 第四節 美利達工業股份有限公司簡介 5 第五節 愛地雅工業股份有限公司簡介 6 第六節 研究架構 7 第二章 文獻回顧 9 第一節 國內相關文獻 9 第二節 國外相關文獻 11 第三節 國內外文獻一覽表 12 第三章 研究方法 20 第一節 單根檢定 20 第二節 共整合檢定 22 第三節 向量誤差修正模型(VECM) 24 第四節 迴歸分析 24 第四章 實證分析 26 第一節 資料來源與處理 26 第二節 敘述統計 31 第三節 單根檢定 32 第四節 共整合檢定 33 第五節 向量誤差修正模型(VECM) 33 第六節 複迴歸模型 35 第五章 結果分析與建議 38 第一節 結果分析 38 第二節 建議 39 參考文獻 40 附錄一 巨大工業股份有限公司沿革 43 附錄二 美利達股份有限公司沿革 47 附錄三 愛地雅股份有限公司沿革 57 圖目錄 圖1-6 研究架構 8 圖4-1-1 台灣自行車業總出口產值(百萬元,美金) 27 圖4-1-2 台灣股價大盤指數(TWII,當日收盤價) 27 圖4-1-3 巨大股價(9921,當日收盤價) 28 圖4-1-4 美利達股價(9914,當日收盤價) 28 圖4-1-5 愛地雅股價(8933,當日收盤價) 29 圖4-1-6 國際原油價格(西德州,美元) 29 圖4-1-7 台灣工業生產指數 30 表目錄 表1-3 巨大公司基本資料 4 表1-4 美利達公司基本資料 5 表1-5 愛地雅公司基本資料 6 表2-3 國內外相關文獻整理 12 表4-1 資料來源一覽表 26 表4-3-1 ADF 單根檢定 32 表4-3-2 單根檢定-一階差分 32 表4-4-1 共整合檢定 33 表4-5-1 Giant & Merida 向量誤差修正模型 34 表4-5-2 Giant & Ideal 向量誤差修正模型 34 表4-5-3 Merida & Ideal 向量誤差修正模型 34 表4-6-1 自行車產業與景氣循環對巨大股價之影響 37 表4-6-2 自行車產業與景氣循環對美利達股價之影響 37 表4-6-3 自行車產業與景氣循環對愛地雅股價之影響 37
202

Relationships among quality of life, self-care, and affiliated individuation in persons on chronic warfarin therapy

Goldstein, Leigh Ann 31 October 2013 (has links)
This descriptive, correlational, cross-sectional study explored the relationships among the variables self-care action, self-care knowledge, and affiliated individuation and quality of life for persons on chronic warfarin therapy. This study also explored the moderating effects of self-care knowledge and affiliated individuation on quality of life. This research was guided by a theoretical framework based on modeling and role-modeling theory (Erickson, Tomlin, & Swain, 1983). The sample consisted of 83 adults between the ages of 30 to 91 years. The majority of participants were Caucasian, educated, retired and almost evenly distributed between male and female. Each subject completed the following instruments: the Oral Anticoagulation Knowledge (OAK) test, the Duke Anticoagulation Satisfaction Scale (DASS), the Basic Needs Satisfaction Inventory (BNSI), and the generic quality of life survey (SF36v2). Data was analyzed using correlation and hierarchical multiple regression analysis. Results indicated significant correlations among most of the study variables. Self-care action significantly explained variances in all but two quality of life variables. Self-care knowledge and affiliated individuation had statistically significant moderating effects on the DASS negative impact and hassles/burdens subscales. Self-care knowledge also demonstrated a significant moderating effect on the SF36v2 physical function subscale. These findings support the concepts proposed by the study's theoretical framework. This research serves as validation of Acton's (1997) study findings for the concept of affiliated individuation and its value as a self-care resource in a specific clinical population. / text
203

Metoder för informationsoptimering vid organisk syntes

Nordahl, Åke January 1990 (has links)
<p>Diss. (sammanfattning) Umeå : Umeå universitet, 1990, härtill 5 uppsatser.</p> / digitalisering@umu.se
204

On the Measurement, Theory and Estimation of Fiscal Multipliers

Gechert, Sebastian 10 November 2014 (has links) (PDF)
The study is intended to identify relevant channels and possibly biasing factors with respect to fiscal multipliers, and thus to contribute to improving the precision of multiplier forecasts. This is done by, first, defining the concept of the multiplier used in the present study, presenting the main theoretical channels of influence as discussed in the literature and the problems of empirical identification. Second, by conducting a meta-regression analysis on the reported multipliers from a unique data set of 1069 multiplier observations and the respective study characteristics in order to derive quantitative stylzed facts. Third, by developing a simple multiplier model that explicitly takes into account the time elapse of the multiplier process as an explanatory factor that has been largely overlooked by the relevant theoretical literature. Fourth, by identifying, for US macroeconomic time series data, the extent to which fiscal multiplier estimates could be biased in the presence of financial cycles that have not been taken into account by the relevant empirical literature.
205

Population Dynamics And Factors Affecting Spiny Lobster Small Scale Fisheries

Luna, Soledad 05 June 2018 (has links) (PDF)
This dissertation analyses the effects of current fisheries practices and management regulations of the green spiny lobster (Panulirus gracilis) in the Eastern Tropical Pacific Region (ETP). P. gracilis has reached a critical state in the ETP. Country-based studies report that between 60 and 98% of lobsters caught in the wild are under the minimum landing size (MLS). This means that spiny lobsters are being extracted before reproducing and contributing to the replenishment of interconnected populations. The recovery of green spiny lobster populations in the ETP and the future maintenance of a sustainable fishery will depend on effective management decisions and on taking in account environmental factors that influence the population dynamics of the lobsters. In the first study (Chapter 2), the B52 Spiny Lobster individual based simulation model was used for conducting a population viability analysis to quantify the effect of current fishing practices and the effect of varying management regulations on minimum landing size (MLS) and fishing effort. The best suit of regulations to maintain the highest abundance, production of offspring and catch is to protect juveniles and egged females, and to establish a MLS that assures the reproduction of individuals before being extracted. This study revealed regional variations, however the patterns and the causes for variation were not yet clear. This led to the next chapters in this dissertation. In Chapter 3, I used a meta-analysis to explore regional lobster variability by comparing published studies from the ETP. The objective was to identify patterns of variation related to geographic and environmental factors of the region that can inform the establishment and evaluation of coordinated regulations. Morphological relationships showed to be more variable at northern latitudes, where the mean annual sea surface temperatures are higher than at lower temperatures at the Equator. In terms of management, MLS regulations should be adapted accounting for the effect of sea surface temperature and its variation. Additionally, it was observed that monitoring methodologies are not standardized within the region and even in some cases, neither within countries. Furthermore, in most places monitoring of the spiny lobster fishery happens sporadically, only in Galapagos takes place every year. Identifying patterns of variations can improve the accuracy of prediction models which can help to explore, design, and apply more effective management measures, as well as promote regional coordination to support the recovery and maintenance of spiny lobsters. In Chapter 4, I contrast current Ecuadorian minimum landing size (MLS) regulation to lobster empirical measurements within Ecuador in order to recognize potential pitfalls for management enforcement. I used linear regression and multiple regression models with the objective of identifying potential relative size variations of the individuals caught in the wild over time and in the different fishing areas in Ecuador, as well as to analyse the effect of locality, sex, age and mean SST on the tail length/total length ratio. Morphological relations were significantly different among sexes, in time and by all sites. Most importantly, this study shows that current minimum size regulations are not applicable to all sites. Additionally, I found that water temperature has a significant effect on morphological relationship variations. However, it was not the main site-specific variable responsible for explaining such variations. In general, this work emphasizes the need for length data collection standardization and the consideration of temporal and spatial variation implications in national and regional fishery management planning, enforcement and evaluation.
206

Structural equation modelling

Mohanlal, Pramod 06 1900 (has links)
Over the past two decades there has been an upsurge in interest in structural equation modelling (SEM). Applications abound in the social sciences and econometrics, but the use of this multivariate technique is not so common in public health research. This dissertation discusses the methodology, the criticisms and practical problems of SEM. We examine actual applications of SEM in public health research. Comparisons are made between multiple regression and SEM and between factor analysis and SEM. A complex model investigating the utilization of antenatal care services (ANC) by migrant women in Belgium is analysed using SEM. The dissertation concludes with a discussion of the results found and on the use of SEM in public health research. Structural equation modelling is recommended as a tool for public health researchers with a warning against using the technique too casually. / Mathematical Sciences / M. Sc. (Statistics)
207

Modelos para relacionar variáveis de solos e área basal de espécies florestais em uma área de vegetação natural / Models to relate variable soil and basal area of forest species in an area of natural vegeration

Simone Grego 08 October 2014 (has links)
O padrão espacial de ocorrência de atributos de espécies florestais, tal como a área basal das árvores, pode fornecer informações para o entendimento da estrutura da comunidade vegetal. Uma vez que fatores ambientais podem influenciar tanto o padrão espacial de ocorrência quanto os atributos das espécies em florestas nativas. Desse modo, investigar a relação entre as características ambientais e o padrão espacial de espécies florestais pode ajudar a entender a dinâmica das florestas. Especificamente, neste trabalho, o objetivo é avaliar métodos estatísticos que permitam identificar quais atributos do solo são capazes de explicar a variação da área basal de cada espécie de árvore. A área basal foi considerada como variável resposta e como covariáveis, um grande número de atributos físicos e químicos do solo, medidos em uma malha de localizações cobrindo a área de estudo. Foram revisados e utilizados os métodos de regressão linear múltipla com método de seleção stepwise, modelos aditivos generalizados e árvores de regressão. Em uma segunda fase das análises, adicionou-se um efeito espacial aos modelos, com o intuito de verificar se havia ainda padrões na variabilidade, não capturados pelos modelos. Com isso, foram considerados os modelos autoregressivo simultâneo, condicional autoregressivo e geoestatístico. Dado o grande número de atributos do solo, as análises foram também conduzidas utilizando-se as covariáveis originais, fatores identificados em uma análise fatorial prévia dos atributos de solo. A seleção de modelos com melhor ajuste foi utilizada para identificar os atributos de solo relevantes, bem como a presença e melhor descrição de padrões espaciais. A área de estudo foi a Estação Ecológica de Assis, da Unidade de Conservação do Estado de São Paulo em parcelas permanentes, dentro do projeto \"Diversidade, Dinâmica e Conservação em Florestas do Estado de São Paulo: 40 ha de parcelas permanentes\", do programa Biota da FAPESP. As análises reportadas aqui se referem à área basal das espécies Copaifera langsdorffii, Vochysia tucanorum e Xylopia aromatica. Com os atributos de solo reduzidos e consistentemente associados à área basal, a declividade, altitude, saturação por alumínio e potássio mostraram-se relevantes para duas das espécies. Resultados obtidos mostraram a presença de um padrão na variabilidade, mesmo levando-se em consideração os efeitos das covariáveis, ou seja, os atributos do solo explicam parcialmente a variabilidade da área basal, mas existe um padrão que ocorre no espaço que não é capturado por essas covariáveis. / The spatial pattern of occurrenceis of forest species and their attributes, such as the basal area of trees, can provide information for understanding the structure of the vegetable community. Considering the environmental factors can influence the spatial pattern of occurrences of species in native forests and related attributes, describing relationship between environmental characteristics and spatial pattern of forest species can be associated with the dynamics of forests. The objective of the present study is to assess different statistical methods used to identify which soil attributes are associated with the basal area of each tree selected species. The basal area was considered as the response variable and the covariates are given by a large number of physical and chemical attributes of the soil, measured at a grid of locations covering the study area. The methods considered are the multiple linear regression with stepwise model selection, generalized additive models and regression trees. Spatial effects were added to the models, in order to ascertain whether there is residual spatial patterns not captured by the covariates. Thus, simultaneous autoregressive model, autoregressive conditional and geostatistical were considered. Considering the large number of soil attributes, analysis were were conducted both ways, using the original covariates, and using factors identified in a preliminar factor analysis of the soil attributes. Model selection was used to identify the relevant attributes of soil as well as the presence and better description of spatial patterns. The study area was the Ecological Station of Assis, the Conservation Unit of the State of São Paulo in permanent plots within the \"Diversity Dynamics and Conservation Forests in the State of São Paulo: 40 ha of permanent plots\" project, under the research project FAPESP biota. The analyzes reported here refer to the basal area of the species Copaifera langsdorffii, Vochysia tucanorum and Xylopia aromatica. Results differ among the considered methods reinforcing the reccomendation of considering differing modeling strategies. Covariates consistently associated with basal area are slope, altitude and aluminum saturation, potassium, relevant to at least two of the species. Results obtained showed the presence of patterns in residual variability, even taking into account the effects of covariates. The soil characteristics only partially explain the variability of the basal area and there are spatial patterns not captured by these covariates.
208

Dinâmica espacial e contingências socioambientais da hanseníase no Estado do Maranhão: avaliação de riscos e vulnerabilidade em áreas hiperendêmicas / Spatial dynamics and socio and environmental contingencies of leprosy in Maranhão state: risk assessment and vulnerability in hyperendemic areas

Mauricio Eduardo Salgado Rangel 22 September 2016 (has links)
A hanseníase, doença crônica estigmatizante com potencial de causar danos neurológicos, resulta da infecção pelo Mycobacterium leprae. Análises epidemiológicas atuais têm utilizado ferramentas clínicas e de análise espacial para o mapeamento dos principais focos de ocorrência de doenças e de áreas de alto risco. Analisar os municípios maranhenses quanto à distribuição dos casos de hanseníase torna-se uma ferramenta a mais na prevenção e controle da Hanseníase no estado por inúmeros fatores: comporta-se como área hiperendêmica de hanseníase; apresenta fluxo migratório intenso com outras cidades de forma interestadual; e tem grandes contrastes sociais marcados por pouca, ou nenhuma, infraestrutura básica em algumas áreas dos vários municípios deste. Objetivos: Analisar a distribuição espaço-temporal da hanseníase para o estado do Maranhão, no período de 2001 a 2013. Identificar a ocorrência de agrupamentos espaços-temporais de provável alta transmissão (risco) e verificar se há associação dessa distribuição de taxas de detecção de risco relativo (RR) da doença com as variáveis do contexto geográfico como socioeconômicas e ambientais. Metodologia: A fonte de coleta dos dados clínicos e epidemiológicos foi o Sistema de Informação Nacional de Agravos Notificáveis do Ministério da Saúde e dos dados demográficos, ambientais e bases cartográficas digitais do Instituto Brasileiro de Geografia e Estatística. Foi adotada uma abordagem ecológica sobre tendências dos padrões espaçostemporais de transmissibilidade, com utilização dos métodos: varredura espacial (scan), para a identificação dos agregados (clusters) de risco, considerando o modelo de distribuição de probabilidade Discreto de Poisson; Estimador Bayesiano Empírico para a suavização local de taxas, a partir de informações de municípios vizinhos tendo como estratégia de construção o critério da contiguidade; regressão múltipla espacial considerando uma modelagem com distribuição de Poisson no contexto Bayesiano, levando em conta a dependência espacial, com o propósito de avaliar a relação entre a ocorrência da variável dependente com as variáveis demográficas, socioeconômicas e ambientais. Resultados: A taxa média de detecção foi de 6,73 casos por 10.000 hab., com 53.826 casos notificados no período. O estudo revelou que a distribuição dos casos de sexo masculino (57,75%) apresentou maior proporção em relação ao feminino (42,25%), havendo predominância da doença na faixa etária >15 anos (89,87%). A alta ocorrência na classificação operacional multibacilar (60,10%) é um forte indicativo decorrente do longo período de incubação da doença somado ao não diagnóstico precoce. A análise da distribuição dos agregados espaciais identificou 14 (7 de risco alto e 7 de risco baixo) e 6 (3 de risco alto e 3 de risco baixo) agrupamentos espaciais, considerando-se 10% e 50% da população em risco, respectivamente, em áreas com taxas de detecção alta e que possuem baixa qualidade de vida. O estimador Bayesiano empírico local possibilitou gerar índices corrigidos e com menores instabilidades. A análise de regressão múltipla espacial mostrou que as variáveis índice Gini, bioma predominante cerrado/caatinga e percentual de população urbana tiveram associação positiva e significativa para explicar o risco relativo (RR) no estado do Maranhão. Conclusões: O estudo mostrou que existem aglomerados com elevado risco para transmissão da hanseníase no estado do Maranhão. A associação entre o risco relativo da hanseníase e o percentual de população urbana indica que a hipótese que associa o M. leprae e a população que vive em condições de acentuada desigualdade socioeconômica ainda é forte. Essa hiperendemicidade pode demonstrar que o crescimento da população urbana é um preditor de incidência da hanseníase, face à urbanização descontrolada e ao fluxo de migrantes advindos de diferentes espaços rurais. Foi possível identificar áreas prioritárias para implementação de programas eficazes de controle de hanseníase no estado do Maranhão. / Leprosy, a chronic stigmatizing disease with the potential to cause neurological damage resulting from infection by Mycobacterium leprae. Current epidemiological studies have used clinical and spatial analysis for mapping of the main occurrence of disease outbreaks and high-risk areas. Analyze the municipalities of Maranhão state regarding the distribution of leprosy cases becomes another tool in the prevention and control of leprosy in the state by numerous factors like behaves as hyper-endemic area of leprosy; It presents intense migration to other interstate cities; and has great social contrasts marked by little or no basic infrastructure in some areas of several municipalities.. Objectives: To analyze the spatiotemporal distribution of leprosy in the Maranhão state, from 2001 to 2013. To identify the spatiotemporal clusters occurrence of probable high transmission (risk) and check for association of this distribution of relative risk (RR) detection rates of the disease with the variables of geographic context as socioeconomic and environmental. Methodology: Clinical and epidemiological data was obtained from the Ministry of Healths Disease Reporting System and demographic data, environmental and digital cartographic bases were obtained from the Brazilian Geography and Statistics Institute. An ecological approach to trends transmissibility of spatiotemporal patterns, using the methods: spatial scan to identification the clusters of risk, considering the Discrete Poisson probability distribution model; empirical Bayesian method was applied for local rate flattening, using data from municipalities having as building strategy the criterion of contiguity; ecological regression modeling with considering a Poisson distribution in the Bayesian context, taking into account the spatial dependence, in order to evaluate the relationship between the occurrence of the dependent variable with demographic, socioeconomic and environmental variables. Results: The mean detection rate was 6.73 cases per 10,000 inhabitants, with 53,826 reported cases. The study revealed that the distribution of male cases (57.75%) showed a predominance over female (42.25%), with predominance of the disease in the age group upper than 15 years (89.87%). The high occurrence in operational classification multibacillary (60.10%) is a strong indication due to the long incubation period of the disease added to no early diagnosis. The analysis of the distribution of spatial clusters identified 14 (7 high risk and 7 low risk) and 6 (3 high risk and 3 low risk) spatial clusters, considering 10% and 50% of the population at risk in areas with high detection rates and which have low quality of life. Local empirical Bayes estimator allowed to generate fixed and minor instabilities indexes. The best results of modeling to spatial multiple regression analysis for the relative risk (RR) presented for the variables Gini index, cerrado/caatinga biome and percentage of urban population. Conclusions: The study showed that there are clusters at high risk for transmission of leprosy in the Maranhao state. The association between the relative risk of leprosy and the percentage of urban population indicates that the hypothesis that associates M. leprae and the population living in severe socioeconomic inequality is still strong. This hyperendemicity can demonstrate that the growth of the urban population is a predictor incidence of leprosy due to uncontrolled urbanization and the influx of migrants coming from different rural areas.It was possible to identify priority areas for implementation of effective leprosy control programs in the Maranhão state.
209

Efeitos de sistemas de operação e condições ambientais na abundância de Hoplias aff. malabaricus (Bloch, 1794) em reservatórios neotropicais: um estudo de caso no Rio Iguaçu / Effects of systems operation and environmental conditions in the abundance of Hoplias aff. malabaricus (Bloch, 1794) in neotropical reservoirs: a case study in the Iguaçu River

Benelle, Cristina Aparecida 27 September 2010 (has links)
Made available in DSpace on 2017-07-10T18:13:28Z (GMT). No. of bitstreams: 1 Cristina Aparecida Benelle.pdf: 285891 bytes, checksum: 2c3bc6c8c3e76bcfd74a142405d31ec5 (MD5) Previous issue date: 2010-09-27 / This study aimed to investigate regulatory mechanisms of an abundance of piscivorous fish in Neotropical reservoirs, and the effects of different types of operating systems. For the study were collected bimonthly from July 2003 to January 2010 fish and limnological variables, sampled at seven locations, four in Salto Santiago reservoir and three in the Salto Osório reservoir. The sampling of fish were taken with gillnets with different mesh size (between 2.4 and 16.0 cm) and trammel net (between 6.0 and 8.0 cm) opposite knots, exposed for 24 h. Abiotic variables such as water temperature, dissolved oxygen, conductivity, pH and water transparency were measured in situ with portable equipment, for the other analysis was collected with the aid of water bottle of Van Dorn, used in subsequent analysis performed in the laboratory. In order to evaluate the effect between the biotic (CPUE transformed into log (x +1)), abiotic, operating systems and sampling in the marginal areas, data were submitted to multiple regression (backward stepwise) with variables indicator, and used the correlation matrix between the predictor variables in order to check possible sources of multicollinearity. Chemical analysis performed was found that the species showed different patterns of abundance in the reservoirs, as well as their prey, which was possibly a reflection of operating systems, also showing an increase in the abundance of species in the marginal area. / Esse trabalho teve por objetivo investigar mecanismos reguladores da abundância populacional Hoplias aff. malabaricus em reservatórios neotropicais, bem como os efeitos dos diferentes tipos de sistemas de operação. Para iss os peixes e variáveis limnológicas foram coletados bimestralmente entre julho de 2003 à janeiro de 2010 de peixes e variáveis limnológicas, amostrados em sete locais, sendo quatro no reservatório de Salto Santiago e três no reservatório de Salto Osório. As amostragens de peixes ocorreram com redes de espera simples de malhas 2,4 a 16 cm e tresmalhos de 6 a 8 cm de entre nós não adjacentes, expostas por 24 h. Variáveis abióticas como: temperatura da água, oxigênio dissolvido, condutividade elétrica, pH e transparência da água foram medidos "in situ" com equipamentos portáteis e, para as demais análises, a água foi coletada com auxílio de garrafa de Van Dorn, utilizada em análises posteriores efetuadas em laboratório. Com a finalidade de avaliar o efeito entre os fatores bióticos (CPUE transformados em log(x+1)), abióticos, sistemas de operação e amostragens na área marginal, os dados foram submetidos ao procedimento de regressão múltipla (backward stepwise) com variáveis indicadoras, sendo usada a matriz de correlação entre as variáveis preditoras a fim de verificar possíveis fontes de multicolinearidade. Através das análises realizadas foi verificado que a espécie apresentou diferentes padrões de abundância nos reservatórios, assim como suas presas, o que possivelmente foi reflexo dos sistemas de operação, mostrando também um incremento na abundância da espécie na região marginal.
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Mapping articulatory parameters on formant patterns : From articulations to acoustics non-stop

Cortes, Elisabet Eir January 2010 (has links)
The traditional way of estimating the formant frequencies from articulatory data presupposes knowledge of how the vocal tract cross-sectional area varies for a given articulatory shape (Fant 1960/1970). Accordingly, in order to derive the formant pattern of a given articulation, the three-dimensional shape of the vocal tract (VT) needs to be known. In the past cross-sectional areas have typically been derived by means of ‘d-to-A rules’ that use the mid-sagittal cross-distance d at each point along the VT to produce a corresponding cross-sectional area A. X-ray and MRI data have been used to calibrate such rules (Heinz &amp; Stevens 1964, Sundberg et al. 1987, Ericsdotter 2005). Although this procedure has produced many useful results it is time consuming and laborious. It is speaker-specific. It presupposes access to information on the three-dimensional shape of the VT, which is not experimentally readily accessible. Such observations raise the question whether sufficiently accurate alternative approaches can be developed. Is it possible to go straight from articulatory data to formant frequencies without having to construct a cross-sectional area function? If such methods could be developed it would have many uses both in phonetics and practical applications. This paper reports an attempt to map the time variations of selected articulatory parameters from X-ray profiles directly on the formant tracks using multiple regression analysis. Preliminary results for F1 indicate that multiple regression analysis can indeed be useful for making such predictions. The prospects of extending the present analyses to other formants are discussed.

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