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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.
31

Determinação do tamanho da amostra para avaliação de híbridos de melão amarelo / Determination of sample size to evaluation of yellow melon hybrids

Moura, Kallyo Halyson Santos 30 April 2008 (has links)
Made available in DSpace on 2016-08-12T19:18:43Z (GMT). No. of bitstreams: 1 kallyo halyson santos moura ok.pdf: 596520 bytes, checksum: 9c71d52ee07aced37426fdeafa2cef96 (MD5) Previous issue date: 2008-04-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The sample size in experiments should be determined so that it can accurately estimate the parameters of interest and to save time, labor and resources. The objective of the present work was to determine the sample size in evaluation experiments of melon hybrids in Mossoró. An experiment was carried out in randomized blocks with three replications to evaluate twenty yellow melon hybrids. The experimental plot consisted of two rows of 5.0 m with twenty plants in the spacing of 2.0 x 0.5 m. The traits evaluated were pulp thickness and firmness, content of soluble solids and fruit mean weight. Data were taken plant to plant, identifying each one harvested fruits. The methods used were of bootstrap resampling, linear model in plateau, sampling ntensity and modified maximum curvature to determine the sample size. The sample size recommended to determining for pulp thickness, fruit mean weight, content of soluble solidsand pulp firmness is 13, 13, 9 and 8 fruits, respectively. The Minimum sample size determined by modified maximum curvature method to pulp thickness, fruit mean weight, content of soluble solids and pulp firmness were 6,32; 7,35; 5,32and 3,25, respectively / O tamanho da amostra em experimentos deve ser determinado para que se possa estimar com precisão adequada os parâmetros de interesse e economizar tempo, mão-de-obra e recursos. O objetivo do presente trabalho foi determinar o tamanho da amostra para avaliação de híbridos de melão amarelo. Foi conduzido um experimento em blocos casualizados com três repetições para avaliar vinte híbridos de melão. A parcela utilizada foi constituída por duas linhas de 5,0 m com vinte plantas no espaçamento de 2,0 x 0,5 m. As características avaliadas foram as seguintes: espessura da polpa, firmeza da polpa, teor de sólidos solúveis e peso médio do fruto. Os dados foram tomados planta a planta, identificando cada um dos frutos colhidos. Foram utilizados os métodos de reamostragem bootstrap, modelo linear segmentado com platô, intensidade de amostragem e máxima curvatura para determinar o tamanho da amostra. O tamanho de amostra recomendado para determinação da espessura da polpa, peso médio do fruto, teor de sólidos solúveis e firmeza da polpa é de 13, 13, 9 e 8 frutos, respectivamente. Os tamanhos mínimos da amostra, obtidos pelo método da máxima curvatura modificada, foram 6,32; 7,35; 5,32 e 3,25 para espessura da polpa, peso médio do fruto, teor de sólidos solúveis e firmeza da polpa, respectivamente
32

VERIFICAÇÃO DE TIPOS DE DOSADORES DE SEMENTES DE MILHO E SOJA NO NORTE DO PARANÁ / CHECKING TYPES OF CORN AND SOYBEANS SEED FEEDERS IN NORTHERN PARANÁ

Schmalz, Cassiano Ricardo 10 January 2014 (has links)
The first works with Precision Agriculture in Brazil started with greater intensity from the 2000s in order to know and correct soil fertility. After long years of public-private research generated a vast database of information demonstrating that activities like sowing has become an essential step. Thus, studies on the accuracy in the distribution of seeds and seed distribution in variable density and quality of sowing methods by coefficient of variation (CV) and accuracy rate (IP), have become important tools to increase productivity. To this end, we performed a case study of the performance of types of corn and soybeans seed feeders in northern Paraná, 02 models of pneumatic seeder and 05 mechanical models (honeycomb disc). The experiments conducted during 7 years in 61 different locations, by the technical department of Pioneer Seeds, quantified the losses from failures of seeds in the row. Pneumatic seeders present numerical and statistical superiority both in the soybean as corn. / Os primeiros trabalhos com Agricultura de Precisão iniciaram no Brasil com maior intensidade a partir da década de 2000 com o intuito de conhecer e corrigir a fertilidade do solo. Após longos anos de pesquisa público-privada geraram um vasto banco de informações demonstrando que atividades como a semeadura tornou-se uma etapa fundamental. Assim, estudos relativos à precisão na distribuição de sementes como a distribuição de sementes em densidade variável e qualidade da semeadura, pelos métodos de coeficiente de variação (C.V.) e índice de precisão (I.P.), tornaram-se importantes ferramentas para acréscimo da produtividade. Com este intuito, realizou-se um estudo de caso do desempenho de tipos de dosadores de sementes de milho e soja no norte do Paraná, sendo 02 modelos de semeadora pneumáticas e 05 de modelos mecânicos (disco alveolado). Os experimentos realizados durante 7 anos em 61 locais diferentes, pelo departamento técnico da Pioneer Sementes quantificaram as perdas decorrentes de falhas de sementes na linha de plantio. As semeadoras pneumáticas apresentam superioridade numérica e estatística tanto nas culturas da soja quanto do milho.
33

Automaticity in L2 learning: Correlation between vocabulary proficiency and response time in word recognition

Jonsson, Signe January 2016 (has links)
Automaticity (in this essay defined as short response time) and fluency in language use are closely connected to each other and some research has been conducted regarding some of the aspects involved. In fact, the notion of automaticity is still debated and many definitions and opinions on what automaticity is have been suggested (Andersson,1987, 1992, 1993, Logan, 1988, Segalowitz, 2010). One aspect that still needs more research is the correlation between vocabulary proficiency (a person’s knowledge about words and ability to use them correctly) and response time in word recognition. Therefore, the aim of this study has been to investigate this correlation using two different tests; one vocabulary size test (Paul Nation) and one lexical decision task (SuperLab) that measures both response time and accuracy. 23 Swedish students partaking in the English 7 course in upper secondary Swedish school were tested. The data were analyzed using a quantitative method where the average values and correlations from the test were used to compare the results. The correlations were calculated using Pearson’s Coefficient Correlations Calculator. The empirical study indicates that vocabulary proficiency is not strongly correlated with shorter response times in word recognition. Rather, the data indicate that L2 learners instead are sensitive to the frequency levels of the vocabulary. The accuracy (number of correct recognized words) and response times correlate with the frequency level of the tested words. This indicates that factors other than vocabulary proficiency are important for the ability to recognize words quickly.
34

Avparaffinering  med Xylen versus Ttissue- clear för vävnadsmaterial vid flödescytometrisk analys av DNA ploidi / Xylene versus Tissue-clear as dewaxing agent for tissue samples at flow cytometric DNA ploidy

Genberg, Malin, Ahlgren, Helen January 2017 (has links)
No description available.
35

Effect of Evapotranspiration Rate on Almond Yield in California

Serrano, Dafne Isaac 01 October 2018 (has links)
Since 2011, California has been under drought conditions. These conditions have not only affected water availability for farmers, but also production. California’s second most valuable crop, almonds, has been affected by drought conditions. This study used three models (Model 1-3) to describe almond yield variability from year to year and almond yield variability within a year in Kern County, CA. The study evaluated 185 almond farms that were classified in three locations (east side, west side and north west side). The years of the study were 2011 (wet year) and 2013-2015 (drought condition years). Model 1 determined a functional regression between almond yield and annual evapotranspiration during the 4 years of the study. The R2was 7.9%, meaning low association between both variables and high unexplained variability (92.1%). Model 2 evaluated year to year variation. A regression function between almond yield and annual evapotranspiration after adjusting for location, precipitation, chilling hours and year was made. The R2of this model 62.6%, and all the variables used had a p2was higher than Model 1; however, there was high unexplained variability (47.4%). Model 3 evaluated within-year variation. A regression function between almond yield and annual evapotranspiration after adjusting for tree age and location (east, west and northwest side) was made for each year (2011 and 2013 -2015). Coefficient of variation of evapotranspiration and soil available water storage were analyzed as additional variables in Model 3; however, they were not introduced in Model 3 due to the low increase in R2 in each year (2 of Model 3 for each year were, 60.4%, 49.7%, 53.8% and 53.2% for the years 2011, 2013-2015, respectively. Model 3 also had high unexplained almond yield variability in each year (39.6%-50.3%). This high unexplained variability leads to introduce additional variables to the functional regression model for further studies. Identifying these additional variables and having a functional regression model with high R2 would lead to understand howlow evapotranspiration could potentially lead to a positive response on yield in drought conditions; thus, making farmers improve water use efficiency and hence, lowering production cost. However, the high unexplained variability clearly indicates that evapotranspiration is only one of many factors that influence yield. If improved yield is an important outcome, future studies must examine large- scale almond-producing farms with multiple agricultural system variables.
36

Совершенствование методики оценки уровня конкурентоспособности региона : магистерская диссертация / Improving the methodology for assessing the level of regional competitiveness

Волкова, Е. С., Volkova, E. S. January 2020 (has links)
Regional competitiveness is a complex concept that includes not only economic, but also social, demographic and political aspects. Different indicators that characterize even one aspect of competitiveness can give polar estimates of its level. Taking into account this differentiation is certainly important. The purpose of the final qualification work is to develop methodological foundations for analyzing the competitiveness of the region. The paper studies theoretical and methodological issues of regional competitiveness research, conducts a critical analysis of widely used methods, and offers the author's methodological approach to assessing the level of regional competitiveness. The empirical base of the study was educational and research literature, statistical data of the Federal state statistics service and its territorial divisions, data from the Unified interdepartmental information and statistical system, analytical reports of the Federal state statistics service and its territorial divisions, and data from an expert survey. In the final qualification work, a methodological approach to assessing the level of competitiveness of the region was developed. / Конкурентоспособность региона - комплексное понятие, которое включает в себя не только экономические, но и социальные, демографические и политические аспекты. Различные показатели, характеризующие даже один аспект конкурентоспособности, могут давать полярные оценки ее уровня. Учет такой дифференцированности, безусловно, важен. Целью выпускной квалификационной работы является развитие методических основ анализа конкурентоспособности региона. В работе изучены теоретико-методические вопросы исследования конкурентоспособности региона, проведен критический анализ широко применяемых методик и предложен авторский методический подход оценки уровня конкурентоспособности региона. Эмпирической базой исследования выступили учебно-методическая и научно-исследовательская литература, статистические данные Федеральной службы государственной статистики и ее территориальных подразделений, данные Единой межведомственной информационно-статистической системы, аналитические отчеты Федеральной службы государственной статистики и ее территориальных подразделений, данные экспертного опроса. В выпускной квалификационной работе разработан методический подход к оценке уровня конкурентоспособности региона.
37

Comparative analysis of the relationship between the producer and consumer price index of beef and chicken meat in South Africa from 1991to 2018

Aphane, Thabang Rasehla January 2022 (has links)
Thesis (M.Sc. Agriculture (Agricultural Economics)) -- University of Limpopo, 2022 / Beef and chicken meat play a very crucial role in providing food to South African consumers. However, the rise of food prices in South Africa is viewed to curtail progress and drives consumers into debt and forgone opportunity to access food. Hence, it is of importance to understand the consumer price index (CPI) of meat and the disaggregate components of beef and chicken meat producer price indexes (PPI) as they give a clear insight into how individual commodities contribute to the general and food price inflation. The study aimed to comparatively analyse the relationship between PPI beef and CPI meat as well as PPI chicken meat and CPI meat in South Africa from 1991 to 2018. The objectives of the study were to compare the indexes’ variability, correlation, and causality between the different PPI and CPI components. The objectives were analysed using the Coefficient of variation (CV), the Pearson coefficient correlation, the Granger causality test, and the Vector Error Correction model. The CV findings highlight that PPI beef had high variability (65%) compared to CPI meat (56.7%), whereas PPI chicken meat had low variability (49.2%) compared to CPI meat(56.7%). There was evidence of a positive correlation (0.99) between PPI beef and CPI meat as well as PPI chicken meat and CPI meat using Pearson coefficient correlation. In addition, a long-run relationship was found between PPI beef and CPI meat as well as between PPI chicken meat and CPI meat by using the VEC model. Granger causality results indicated that there was a unidirectional relationship from PPI chicken meat to CPI meat, and independent relationships were found from PPI beef to CPI meat, CPI meat to PPI beef as well as CPI meat to PPI chicken meat. Based on the findings, the study recommends that policymakers, through evaluation of monetary policies, should continue maintaining a specific inflation target range as that will assist in stabilising meat prices in the economy. At the same time, protect meat producers against input price inflation using instruments such as input subsidies, grants, and the provision of modern technologies. / National Research Foundation (NRF)
38

臺灣社會保險所得重分配效果於不同城鄉間之影響

簡雅惠 Unknown Date (has links)
社會安全制度,以社會保險及公共救助為主體,兩者之中尤以社會保險為骨幹,社會保險通常扮演著重要的角色。當中一項重要的功能即為所得(財富)重分配功能,亦即政府借助社會保險之力,達成安定經濟社會與改善國民所得分配不均,以達公平之目標。 本文在實證方法上採用「吉尼係數法」與「變異係數法」來計算社會保險的所得重分配效果。利用民國八十五年至民國九十一年行政院主計處「中華民國臺灣地區家庭收支調查報告」之調查資料,探討臺灣地區所得分配不均度上升的原因是否來自於城鄉差異,其次是社會保險政策對於平衡城鄉差距是否有助益。 為了衡量社會保險的所得重分配效果是否會因城鄉發展程度之不同而有所差異,將臺灣地區內之城市分為都市、城鎮及鄉村三級,其分層標準係依照行政院主計處「中華民國臺灣地區家庭收支調查報告」之標準分類。本研究以城鄉別與社會保險為研究主軸,探討臺灣社會保險的所得重分配效果是否在不同城鄉間會有所影響。 綜合研究結果及分析,對於民國八十五至九十一年社會保險實施的所得重分配效果所得到的結論為:1.臺灣地區自民國八十五年後無論是區分層級或整體所得分配效果上的吉尼係數均有逐漸縮小的趨勢,代表政府對於平均所得分配之努力是有所成效的。2.在吉尼係數法下,除了「都市層」外,社會保險實施後「城鎮層」、「鄉村層」與整體所得分配效果的吉尼係數值均高於較社會保險實施前,顯示社會保險政策在平衡城鄉所得差異上的力量似乎薄弱了些。3.在變異係數法下,無論是分層效果或是整體效果實施社會保險後整體的所得分配平均化力量均減弱,故社會保險政策在平均所得分配的效果上似乎沒有達到預期的成效。4.綜合上述兩種方法,除了吉尼係數法下的「都市層」有達成社會保險的所得重分配效果外,吉尼係數法與變異係數法的其他層級和整體效果分析均顯示出實施社會保險未達成所得重分配的效果。 / Social insurance and public rescue are two main components of social security system. Especially, social insurance is also the skeleton of social security system, which has many important functions, one of which is improving the inequity of people’s income assignment. It means that the government redistributes people’s income through social insurance to achieve the goal of equity and further to stabilize economic society. This article uses the data of "Republic of China Taiwan area family budget survey reported", which comes from 1996 to 2002 Directorate-General of Budget, Accounting and Statistics, Executive Yuan, R.O.C.(Taiwan), as investigation material. We calculate the income redistribution effect of social insurance by means of "Gini Coefficient method" and "Coefficient of Variation method". This article has two issues, one of which discusses whether the income inequality in Taiwan does come from the difference between city and countryside. The other one is the benefit of social security policy to balance of disparity of city and countryside. In order to assess whether the income redistribution effects of social security has the difference between cities, we divide the cities in Taiwan into three groups: metropolis, countries and villages, according to standard classification of the investigation material. We use difference between cities and social insurance as two axes of our study to evaluate the effect of income redistribution between different cities. To the effect of social insurance on income redistribution from 1996 to 2002, our study has following findings. First, regardless of classification or summation analysis, the Gini coefficient of income redistribution was gradually reducing from 1996 to 2002. This means that income redistribution policy of government is effective. Second, in Gini Coefficient method, country group and village group had higher Gini Coefficient than before executing social insurance policy. The conclusion shows the influence of social insurance was still not efficient. Third, in Coefficient of Variation method, classification and summation analysis both revealed income redistribution was weaker than before executing social insurance policy, so the policy did not achieve the expected effect. From the above findings, although the metropolis group in Coefficient method did improve income redistribution, other analysis did not achieve the goal of income redistribution.
39

La diseguaglianza di opportunità in Italia / INEQUALITY OF OPPORTUNITY IN ITALY / Inequality of Opportunity in Italy

PACE, MARIA LUCIA 13 October 2017 (has links)
La diseguaglianza dei redditi è comunemente analizzata e misurata attraverso l’impiego di varie misure quali l’indice di Gini, il coefficiente di variazione, l’indice di Theil, la varianza dei logaritmi ed altri ancora (Sen, 1970). A partire dagli anni ’90 l’applicazione di tecniche di scomposizione relative, ad esempio, all’indice di Theil hanno reso possibile quantificare due diverse componenti della diseguaglianza ovvero la disuguaglianza legata allo sforzo individuale e la disuguaglianza dovuta alle ineguali opportunità. Questa seconda componente dipende esclusivamente da fattori esogeni, non controllabili dall’individuo, e, per questa ragione, è a ragione considerata una diseguaglianza “ingiusta”. Alla componente residua della scomposizione è di solito attribuito, invece, il significato di disuguaglianza nello sforzo, ovvero quanto ciascun individuo si è impegnato per raggiungere un determinato obiettivo di successo economico. L’applicazione di questo approccio alle misure di diseguaglianza ha permesso di studiare quale tipo di disuguaglianza prevalga all’interno di un Paese e, soprattutto, quali siano le circostanze esogene che incrementano la disparità nelle opportunità. Il presente lavoro si muove lungo questa linea di ricerca proponendo un metodo per testare il peso relativo delle due componenti e la loro significativita’. Come misura di diseguaglianza si e’ scelto di considerare il coefficiente di variazione in modo da ricondurre il test ad un problema di Analisi della varianza (ANOVA) a piu’ vie. Il test viene presentato facendo riferimento ai dati dell’ISTAT e dell'indagine Bankitalia sui redditi delle famiglie. Dopo quest'analisi preliminare sulle determinanti della diseguaglianza di opportunità in Italia, si utilizza la scomposizione della diseguaglianza nelle sue due componenti: diseguaglianza di opportunità e diseguaglianza legata all'impegno, per definire univocamente l'effetto della diseguaglianza sulla crescita economica. L'analisi econometria è svolta sui dati dell'indagine sulla ricchezza e sui redditi delle famiglie forniti dalla Banca d'Italia. L'effetto viene stimato utilizzando il modello panel dinamico con il metodo di stima GMM. / While the analysis of inequality has been central to economic studies for cen- turies, in recent years many studies concentrated on the distinction between in- equality of opportunity (IO) and inequality of returns to effort (IE) and attempted empirical estimates of the two components, e.g. in US and in Europe. The decompo- sition of a general inequality index into these two components allows to analyze the prevalence of fair or unfair income inequality within a country. This paper suggests to test the differences between the two sources of inequality in a simple way using the ANOVA framework adapted to decompose the coefficient of variation, to better suit the requirements of an inequality index. The proposed procedure is applied to the Italian Survey on Income and Living Condition (IT-SILC data, wave 2005 and 2011). The analysis of the results help identifying the circumstances that foster the rise of inequality of opportunities in Italy. Our analysis shows in particular, that father education, region of residence and gender result as the most relevant circumstances determining inequality of opportunity. On the other side, the role of mother education starting from a lower level, as an inequality of opportunity factor, is increasing its influence over time. The decomposition of inequality index in two components allows not only to analyze the prevalence of fair or unfair income inequality in a country, but also to find a clearer relation between inequality and growth. In fact, it is still missing an analysis of the relation between inequality of opportunity and economic growth in Italy. This paper aims at filling in that gap, by using Italian data from Bank of Italys Survey on Income and Wealth from 1998 to 2014. We choose the coefficient of variation to measure inequality of opportunity at the regional level and, then, we studied its relation with economic growth using Dynamic Panel Data models estimated through System- GMM. Finally, in order to check if the coefficient of variation could be a measure as good as the Entropy’s index, I will compare the results of the estimated panel models with the two different inequality of opportunity indeces. We evaluate the effect of inequality of opportunity on different length of the economic growth rate, going from a short term (2 years) to a very long term growth rate (10 years). Our results shows that, in Italy, inequality of opportunity is negative in the short period, but it does not have any effect on long run growth.
40

Uniformidade de mistura das rações e seu efeito no desempenho de frangos de corte / Feed mix uniformity and its effect on performance of broilers

Rocha, Alexandre Gomes da 23 June 2014 (has links)
The aim of this study was to compare different indicators used on quality control to access the feed mixture uniformity, and were made correlation analysis between the analytical methods used to measure de indicators employed. On a following step, it was evaluated the effect of lack of feed mixture homogeneity on performance of broilers. In the first step, after the analysis of feed mixer efficiency, nine indicators of dry mixture efficiency and two for wet mixture were compared. On the mixer efficiency tests were observed inconstant values of coefficient of variation (CV) after the time needed to achieve CV below 5%. On the comparison of the indicators of dry mixture, five of them presented mean coefficients of variation (CVs) less than 5%, and on the wet mixture indicators comparison test one indicator presented this result. On the correlation analysis, no expressive results were observed, and then the use of alternative methods on the analysis of the indicators can t be justified by this means. On the second step, broilers were reared in four productive phases, with diets with CVs between 5.35 e 49.48%, and were evaluated performance and uniformity of weights of these animals. The obtained results showed that the diets with CVs up to 22.63% cause no effects on the performance of broilers with age above than 12 days. The lack of uniformity of the diets with CV up to 49.48%, don t affect the uniformity of weights of broilers during the rearing period and at slaughter. Concluding the study, it was developed a computer system to guide evaluations of mixture efficiency on industrial equipment of feed production. / Objetivou-se comparar diferentes indicadores utilizados no controle de qualidade para a determinação da eficiência de mistura de rações, e realizaram-se análises de correlações entre os métodos analíticos utilizados na mensuração dos indicadores empregados. Em etapa complementar, avaliou-se o efeito da falta de homogeneidade de mistura das rações sobre o desempenho de frangos de corte. Na primeira etapa, após análise da eficiência do equipamento de mistura foram comparados nove indicadores de eficiência de mistura seca e dois de mistura úmida. Nos testes de eficiência de mistura constataram-se valores inconstantes do coeficiente de variação (CV) após o tempo necessário para atingir CV inferior a 5%. Na comparação de indicadores de mistura seca, cinco destes apresentaram coeficientes de variação (CVs) médios menores do que 5% e no teste comparação de indicadores de mistura úmida, com um dos indicadores obteve-se este resultado. Nas análises de correlações não se observaram valores expressivos que justifiquem o emprego de métodos alternativos de análises dos indicadores. Na segunda etapa, frangos de corte foram criados em quatro fases produtivas, com rações com CVs entre 5,35 e 49,48%, e foram avaliados o desempenho zootécnico e a uniformidade dos pesos destes animais. Os resultados obtidos indicaram que rações com CVs até 22,63%, não causam efeitos sobre o desempenho zootécnico dos frangos de corte com idade superior a 12 dias. A falta de uniformidade das rações, com CV até 49,48%, não afeta a uniformidade dos pesos dos frangos de corte durante o crescimento e no momento do abate. Concluindo o estudo, foi desenvolvido um sistema computacional orientativo para avaliações de eficiência de mistura em equipamentos industriais de produção de rações.

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