1,720,965 research outputs found
Proposition of algorithms based on image analysis to recommend the dose of nitrogen in topdressing in the potato crop
Full text linkO nitrogênio (N) desenvolve papéis obrigatórios na planta, sendo componente da clorofila, aminoácidos, proteínas, ácidos nucleicos, coenzimas e constituintes da membrana. O objetivo do trabalho foi avaliar a proposição de algoritmos baseados em análise de imagens para recomendar a dose de nitrogênio em cobertura na cultura da batata. Os experimentos foram conduzidos na Horta Nova do Departamento de Agronomia da Universidade Federal de Viçosa, no período de junho a setembro dos anos de 2018 e 2019 e foram instalados no delineamento de blocos casualizados, no esquema de parcelas subdivididas, com quatro repetições, cujos tratamentos, na parcela, foram por cinco doses de N em pré-plantio e nas subparcelas por três critérios de recomendação de adubação nitrogenada em cobertura. No momento da amontoa, o clorofilômetro (SPAD) foi utilizado como indicador da necessidade de adubação em cobertura, após a medição na quarta folha a partir do ápice da planta e cálculo do índice de suficiência de N. As variáveis analisadas foram o valor SPAD, quantidade de N aplicado aos 21 dias após a emergência (DAE), produtividade total, produtividade comercial, número de tubérculos comerciais e não comerciais, teor de matéria seca de tubérculos, massa seca da parte aérea, massa seca de tubérculos, teor de matéria seca total, teor de N da quarta folha, teor de N da parte área, teor de N dos tubérculos, quantidade de N absorvido pela parte aérea, tubérculos e total, índice de colheita, eficiência de uso de N, eficiência agronômica de N e eficiência fisiológica de N. Os dados foram avaliados por meio de análise de variância. Para o fator qualitativo as médias foram comparadas pelo teste Tukey a 5% de probabilidade, e para o fator quantitativo foi utilizada análise de regressão. As variáveis foram significativamente influenciadas pela dose de N aplicado no momento do plantio. Os maiores valores das variáveis foram obtidos quando se aplicou de 200 a 300 kg.ha -1 de N. Com relação às variáveis de eficiência de uso de N, eficiência agronômica de N, os melhores valores foram aqueles nos quais se aplicaram em média de 100 a 150 kg.ha -1 de N. Para o experimento que tinha como objetivo verificar a possibilidade de utilizar a análise de imagens digitais na avaliação do status de N da batata, o delineamento foi em blocos ao acaso, no esquema fatorial 5x3 (dose de N x época de avaliação), com quatro repetições. Os tratamentos foram constituídos pelas doses 0, 50, 100, 200 e 300 kg.ha -1 de N, e pelas épocas de avaliação, 21, 48 e 77 dias após a emergência. As avaliações foram realizadas na quarta folha completamente expandida a partir do ápice do ramo principal, avaliando-se as seguintes variáveis: índice SPAD, índices de balanço de nitrogênio (NBI), de Clh e Flv, característica da imagem e teor de N. Na análise de imagem, a superfície foliar foi digitalizada com um scanner de mesa e fotografada com um smartphone. Utilizando os valores médios dos componentes vermelho, verde e azul das imagens, foram calculadas dez diferentes combinações de funções desses planos. As funções nomeadas 3, 7, 8 e 9, tanto para o scanner, quanto para o smartphone, foram as que apresentam os maiores coeficientes de correlação com o SPAD, N total e Chl. Conclui-se que a análise de imagens obtidas por scanner ou smartphone utilizando as funções 3, 7, 8 e 9 estimam adequadamente o status de N da batata. Palavras-chave: Solanum tuberosum L.. Adubação. Nutriente. Agricultura de Precisão. Novas Tecnologias.Nitrogen (N) plays mandatory roles in the plant, being a component of chlorophyll, amino acids, proteins, nucleic acids, coenzymes and membrane constituents. The objective of this work was to evaluate the proposition of algorithms based on image analysis to recommend the dose of nitrogen in topdressing in the potato crop. The experiments were conducted in Horta Nova of the Department of Agronomy of the Federal University of Viçosa, from June to September of the years 2018 and 2019 and were installed in a randomized block design, in a split-plot design, with four replications, whose treatments , in the plot, they were by five doses of N in pre-planting and in the subplots by three criteria of recommendation of nitrogen fertilization in cover. At the time of hilling, the chlorophyll meter (SPAD) was used as an indicator of the need for topdressing fertilization, after measuring the fourth leaf from the apex of the plant and calculating the N sufficiency index. The variables analyzed were the SPAD value, amount of N applied at 21 days after emergence (DAE), total yield, commercial yield, number of commercial and non-commercial tubers, tuber dry matter content, shoot dry mass, tubers dry mass, dry matter content total, fourth leaf N content, area N content, N content of tubers, amount of N absorbed by shoots, tubers and total, harvest index, N use efficiency, N agronomic efficiency and physiologic of N. Data were evaluated by means of analysis of variance. For the qualitative factor, the means were compared using the Tukey test at 5% probability, and for the quantitative factor, regression analysis was used. The variables were significantly influenced by the dose of N applied at the time of planting. The highest values of the variables were obtained when 200 to 300 kg.ha -1 of N were applied. Regarding the variables of N use efficiency, N agronomic efficiency, the best values were those in which they were applied in an average of 100 to 150 kg.ha -1 of N. For the experiment that aimed to verify the possibility of using digital image analysis to evaluate the N status of potatoes, the design was in randomized blocks, in a 5x3 factorial scheme ( N dose x evaluation time), with four replications. The treatments consisted of the doses 0, 50, 100, 200 and 300 kg.ha -1 of N, and the evaluation times, 21, 48 and 77 days after emergence. The evaluations were carried out on the fourth leaf completely expanded from the apex of the main branch, evaluating the following variables: SPAD index, nitrogen balance indices (NBI), Clh and Flv, image characteristic and N content. In image analysis, the leaf surface was scanned with a flatbed scanner and photographed with a smartphone. Using the average values of the red, green and blue components of the images, ten different combinations of functions of these planes were calculated. The functions named 3, 7, 8 and 9, both for the scanner and for the smartphone, were the ones with the highest correlation coefficients with SPAD, total N and Chl. It is concluded that the analysis of images obtained by scanner or smartphone using functions 3, 7, 8 and 9 adequately estimate the N status of potato. Keywords: Solanum tuberosum L.. Nutrient. Fertilizing. Precision Agriculture. New Technologies.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorConselho Nacional de Desenvolvimento Científico e Tecnológic
Qualidade das uvas Niágara Rosada e Isabel em diferentes ambientes no Espírito Santo
Full text linkThe vine is a culture of great national and world expression and many factors can interfere in the wine production as well as the altitude of cultivation. The objective of this study was to evaluate the quality of the varieties (Vitis labrusca L.) NiagaraObjetivou-se com o presente estudo avaliar o comportamento vitícola das variedades de uva Niágara Rosada e Isabel (Vitis labrusca L.) em três diferentes altitudes no município de Santa Teresa-ES. Um diagnóstico nutricional das plantas dos parreirais foi
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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