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The article presents partial results of an ongoing research action, within the scope of the project ?Geodigital Inclusion and Territorial Management of Family-Based Production Units: Generation of Sustainability Index for the Amazon Biome?. This project provides for the definition and availability of indicators of environmental, economic, agricultural, social and governance sustainability, aiming to assist family farmers in the management of the property, subsidizing them in decision making and increasing family income. Embrapa Territorial Intelligence carries out the execution of this research project in partnership with Embrapa Agricultural Informatics, units of the Brazilian Agricultural Research Corporation (Embrapa), headquartered in Campinas, São Paulo (SP), Brazil. The article presents a contribution to the education of the field in Brazil, through a continuous formation action, in the non-formal education modality, through presential and distance training courses, for students of the Agricultural Family School (EFA acronym for which it is known in Brazil) and Rural Family House (CFR acronym for which it is known in Brazil) in the Amazon Biome. This action was based on a training needs diagnosis, conducted through a questionnaire applied to 144 students, distributed between EFA and CFR, located in the Brazilian states of Acre, Amapá, Maranhão, Mato Grosso, Pará, Rondônia and Roraima. The objective of this diagnosis was to identify and analyze the training needs regarding: 1) media, informational and digital skills and competencies of these students; 2) students? level of knowledge and domain of issues related to agricultural production systems and the sustainable development of family agricultural production units. This paper analyzes and presents the result of the diagnosis regarding only the students? media, informational and digital skills and competencies. In this sense, the analysis of these competencies provided the subsidies for the elaboration of a formation and qualification program, oriented under the Pedagogy of Alternance approach, and that considers the specificities and the aspirations of the young students, in search of an education of the field compatible with the local reality and the aspiration of the subjects involved in the process. Made available in DSpace on 2020-09-03T04:40:20Z (GMT). No. of bitstreams: 1 AP-Mediatic-2020.pdf: 424983 bytes, checksum: ce331b349495b0aa51c34f1ef66bbf36 (MD5) Previous issue date: 2020 Na publicação: João Alfredo Carvalho Mangabeira.

This study aimed to define organizational guidelines on advanced quantitative methods and scientific computing (QMSC) for the Brazilian Agricultural Research Corporation (Embrapa), a public institution under the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA). The study was based on a strategic and systemic perspective to support the strengthening of governance of the area of research, development and innovation (RD&I) at Embrapa. This exploratory qualitative study was conducted in two phases. In the first phase, a benchmarking study of organizational model restructuring, especially in areas of QMSC, was carried out in Brazilian and international RD&I institutions. The second phase included an analytical and critical study on the general panorama of QMSC research. Both phases supported the generation of the final result of this study, which was the formulation of a proposal for organizational guidelines for the QMSC area at Embrapa. The study presented the following main results: 1) there is no similarity between the institutions surveyed in the benchmarking and Embrapa, either in terms of the scope of institutional performance, or in relation to the interests focused on organizational innovation in the QMSC area; 2) quantitative methods and scientific computing as areas of expertise and knowledge are widely spread in Brazil, especially at Embrapa, however we did not find equivalence and/or similarity with organizational structure of international institutions. The study highlights the need to expand the scope of the QMSC area at Embrapa, due to the emergence of new fields of activity and new lines of research, for example Data Science. The study recommends Embrapa to prioritize Data Science as a strategic line of research to achieve its results, through research data use and reuse engineering, in order to generate new information and knowledge for decision-making and/or public policy formulation and management. Made available in DSpace on 2020-08-01T11:13:21Z (GMT). No. of bitstreams: 1 AP-Organizational-Guidelines-2020.pdf: 1168994 bytes, checksum: 1edd4d23ae3352718dd48462c16e4314 (MD5) Previous issue date: 2020

Mobile learning is the kind of learning that applies mainly to non-formal education actions from the perspective of continuing education. Within the scope of companies, the demand for educational actions is increasing, notably focused on distance education and training, aimed at both internal and external audiences. However, for the implementation of activities dedicated to mobile learning, it is necessary to develop a digital platform to host the virtual learning environment. Under these conditions, it should be structured in a flexible format and design to encourage interactivity between learners and teachers in the implementation of teaching and learning activities. The article presents and discusses a proposal for a digital mobile platform, called e-Codex, which aims to support educational actions, to promote collaboration and learning, as well as to meet the information dissemination and knowledge generation needs of the Brazilian agroforestry sector. The research was carried out in two phases, the first one consisted of a review of the theoretical-conceptual literature on topics involving cyberspace, digital media and education in virtual spaces, in order to subsidize the development of a digital platform for support the educational actions within the scope of the Embrapa Special Forest Code Project. The second phase of the research consisted in the application of questionnaires to the members of the Special Forest Code Project to know their perceptions and interaction requirements, considered relevant in a digital virtual space, in order to favor horizontal and dialogic relations conducive to new learning. The analysis of the data pointed to the definition of essential elements of the platform design, associating with this, a set of functionalities capable of favoring aspects of interactivity, integration, sharing and exchange of information, knowledge and experiences inherent to virtual learning spaces. The e-Codex Platform incorporates aspects considered important by the research subjects, such as: the need for its creation, their main characteristics and contributions, the possibilities of use, and the forms of organization of the contents and activities offered.

The aim of this study was to model, based on the overall distribution of extreme values, the probability of occurrence of a particular level of annual maximum daily rainfall in three Brazilian regions (Midwest, Southeast and South) and study their behavior over the past 71 years. The parameters of the general distribution of extreme values were estimated by the maximum likelihood method. The Mann–Kendall test showed that there is a positive trend in the annual maximum daily rainfall data series. The non-stationarity was rejected by the augmented Dickey–Fuller test supporting the use of the density function of extreme value distribution to describe the values of the occurrence of annual maximum daily rainfall. The Kolmogorov–Smirnov/Lilliefors goodness-of-fit test showed the good fit of the studied variable to the probability distribution function. The Midwest region has a return period of more frequent annual maximum daily rainfall below 300 mm in comparison with other regions. There is a clear change in the behavior of this extreme event in the Southern region. According to the literature, in past decades annual maximum daily rainfall of 248 mm has been estimated for a return period of 100 years for the state of Santa Catarina-South region, while the results found with the current series, annual maximum daily rainfall of 250 mm was estimated for a return period of 10 years. Extreme annual maximum daily rainfalls for return periods smaller were also found in other regions.

This article presents an outline of model of the educational microcontent production for microtraining, built from the point of view that learning is a relational, intentional and experiential process, and, as such, it results from social interactions that also occur in labour spaces. The model, entitled “production cycle of pedagogical contents (microcontents)” is conceptually anchored in the theoretical precepts of transmedia storytelling and multimedia design, which in turn, are based in aspects of language, communication and cognition, bringing innovative elements capable of favouring leanings. In order to develop the model proposed and presented in the article, inherent conceptions to transmedia storytelling, multimedia design and education, are bound and articulated. Furthermore, one promotes the dialogue between non-formal education in the context of continuous formation and in the interest of technology transfer actions (TT) and of rural extension and technical assistance, for the formulation of microtraining activities via mobile devices. The essence of the model lies in the proposition of a sequence of steps that culminate in the production and organization of technological contents that incorporate pedagogical paths. Those paths serve as learnings favouring routes. It is accepted that this way of producing and organizing contents increases the chances of the subjects involved in the microtraining reflect upon and investigate their practices, abilities and experiences, thus helping them to resignify their realities and to build new rationalities to address their problems. The model “production cycle of pedagogical contents (microcontents)” was built to potentialize the chances of making microtrainings via mobile devices into massive actions that favour the TT process of Brazilian Agricultural Research Corporation (Embrapa), under a constructivist learning approach.

Spatio-temporal modelling is an area of increasing importance in which models and methods have often been developed to deal with specific applications. In this study, a spatio-temporal model was used to estimate daily rainfall data. Rainfall records from several weather stations, obtained from the Agritempo system for two climatic homogeneous zones, were used. Rainfall values obtained for two fixed dates (January 1 and May 1, 2012) using the spatio-temporal model were compared with the geostatisticals techniques of ordinary kriging and ordinary cokriging with altitude as auxiliary variable. The spatio-temporal model was more than 17% better at producing estimates of daily precipitation compared to kriging and cokriging in the first zone and more than 18% in the second zone. The spatio-temporal model proved to be a versatile technique, adapting to different seasons and dates. Resumo A modelagem espaço-temporal é uma área de importância crescente em que modelos e métodos têm sido desenvolvidos para aplicações específicas. Neste estudo, o modelo espaço-temporal foi utilizado na estimativa de dados de precipitação diários. Foram utilizados dados provenientes dos registros pluviométricos de diversas estações meteorológicas, obtidos junto Sistema Agritempo para duas zonas climaticamente homogêneas. Valores de chuva para duas datas fixas (01 de janeiro de 2012 e 01 de maio de 2012) estimados pelo modelo espaço-temporal foram comparados com as técnicas geoestatísticas de krigagem e cokrigagem ordinária, com altitude como variável auxiliar. O modelo espaço-temporal foi superior em mais de 17% em relação às técnicas geoestatísticas de krigagem e cokrigagem para produzir estimativas da precipitação diária para a primeira zona homogênea e mais de 18% para a segunda zona homogênea. O modelo espaço-temporal provou ser uma técnica versátil, adaptando-se nas diferentes épocas e datas estudadas.

Modeling by multiple enchained imputation is an area of growing importance. However, its models and methods are frequently developed for specific applications. In this study the model for multiple imputation was used to estimate daily rainfall data. Daily precipitation records from several meteorological stations were used, obtained from system AGRITEMPO for two homogenous climatic zones. The precipitation values obtained for two dates (Jan. 20th 2005 and May 2nd 2005) using the multiple imputation model were compared with geo-statistics techniques ordinary Kriging and Co-kriging with the altitude as an auxiliary variable. The multiple imputation model was 16% better for the first zone and over 23% for the second one, compared to the rainfall estimation obtained by geo-statistical techniques. The model proved to be a versatile technique, presenting coherent results with the conditions of different zones and times. Resumo A modelagem por imputação múltipla com cadeias encadeadas é uma área de importância crescente cujos modelos e métodos têm sido muitas vezes desenvolvidos para lidar com aplicações específicas. No presente estudo, o modelo de imputação múltipla foi utilizado para estimar os dados de precipitação diária. Foram utilizados registros de precipitação de várias estações meteorológicas, obtidos a partir do sistema Agritempo para duas zonas climaticamente homogéneas. Os valores de precipitação obtidos para duas datas fixas (02 de Maio de 2005 e 20 de Janeiro de 2005) usando o modelo de imputação múltipla foram comparados com as técnicas geoestatisticas de krigagem ordinária e cokrigagem ordinária com a altitude como variável auxiliar. O modelo de imputação múltipla foi mais de 16% melhor para a primeira Zona e mais de 23% melhor para a segunda zona, comparadas com as estimativas de precipitação obtidas pelas técnicas geoestatísticas. O modelo provou ser uma técnica versátil, com resultados coerentes com as condições de diferentes zonas e épocas.

The aim of this study was to model the occurrence of extreme dry spells in the Midwest, Southeast and Southern regions of Brazil and estimate the return period of the phenomenon indicating the time when the occurrence is more severe. The generalized extreme value distribution was the best fit for a series of maximum dry spell number and the parameters estimated by the maximum likelihood method. The data series adherence to the probability distribution was verified by the Kolmogorov–Smirnov test and the percentile–percentile charts. The positive trend of dry spells was verified by the Mann–Kendall test and non-stationarity rejected by Dickey–Fuller and augmented Dickey–Fuller tests. The irregular distribution of rainfall in the growing season for the Midwest region has increased the number of dry spells. The increase of rainy days in the Southeast and the South resulted in a decrease of dry spells in these regions. Regarding the return period of one year, dry spells occurred from 5 to 25 days in the Midwest region meaning a loss of productivity for Brazilian agriculture if it happened between the flowering and grain filling phases, making it, therefore the region with the largest agricultural risk. When the intensity of the dry spells was analyzed for different return periods, the Southern region was the most vulnerable.

The purpose of this study is to evaluate the accuracy of the estimation the monthly mean temperature simulated by the PRECIS model—scenarios A2 and B2 of the IPCC—for Brazilian regions and to develop a Kalman filter to correct the systematic errors of the model for the months of January to June 2010. With a regionalized model, PRECIS aims to reproduce the main features of the climate in complex terrains. The temperature estimates for January to June 2010 are based on linear regression of PRECIS simulations in each pixel of the domain for two time periods, 1961–1990 and 2070–2100. These initial estimates are adapted to 1142 observing stations by a correction using the vertical temperature gradient of the Standard Atmosphere and the difference between model and real topography. The analysis was performed using monthly observed mean temperature data from meteorological stations, along with 1142 simulated data. The PRECIS model with systematic errors was ameliorated by the application of the filter resulting in an improved mean temperature prediction of 66% above the mean square error for the dry months and above 49% for the wet months, for both scenarios under study. At the half-way point, the improvement was 68% for the A2 scenario and 69% for scenario B2.

The semivariogram function fitting is the most important aspect of geostatistics and because of this the model chosen must be validated. Jack knifing may be one the most efficient ways for this validation purpose. The objective of this study was to show the use of the jack knifing technique to validate geostatistical hypothesis and semivariogram models. For that purpose, topographical heights data obtained from six distinct field scales and sampling densities were analyzed. Because the topographical data showed very strong trend for all fields as it was verified by the absence of a sill in the experimental semivariograms, the trend was removed with a trend surface fitted by minimum square deviation. Semivariogram models were fitted with different techniques and the results of the jack knifing with them were compared. The jack knifing parameters analyzed were the intercept, slope and correlation coefficient between measured and estimated values, and the mean and variance of the errors calculated by the difference between measured and estimated values, divided by the square root of the estimation variances. The ideal numbers of neighbors used in each estimation was also studied using the jack knifing procedure. The jack knifing results were useful in the judgment of the adequate models fitted independent of the scale and sampling densities. It was concluded that the manual fitted semivariogram models produced better jack knifing parameters because the user has the freedom to choose a better fit in distinct regions of the semivariogram.

The objective of this paper is to compare three unvaried interpolation algorithms: inverse square distance, minimum curvature and ordinary kriging using observations of annual precipitation average of one thousand and twenty-seven climatic stations including all State of Sao Paulo, representing an area of approximately 248,808.8 km2 (2,91% of the brazilian territory), from 1957 to 1997. The maps of spatial variability didn't present great visual differences, however when the comparison criterion, the mean square error of prediction was calculated for each technique, the great advantage was confirmed by using kriging interpolator. The difference among the observed and predicted values for kriging was much smaller than for the other two methods, indicating to be this the interpolator to be used in the spatial distribution of annual precipitation for this data.

Este trabalho teve por objetivo explorar a aplicabilidade da teoria de fractais no estudo da variabilidade espacial em agregação de solo. A geometria de fractais tem sido proposta como um modelo para a distribuição de tamanho de partículas. A distribuição do tamanho de agregados do solo, expressos em termos de massa, é apresentada. Os parâmetros do modelo, tais como: a dimensão fractal D, medida representativa da fragmentação do solo (quanto maior seu valor, maior a fragmentação), e o tamanho do maior agregado R L foram definidos como ferramentas descritivas para a agregação do solo. Os agregados foram coletados em uma profundidade de 0-10 cm de um Latossolo Vermelho distrófico típico álico textura argilosa, em Angatuba, São Paulo. Uma grade regular de 100 x 100 m foi usada e a amostragem realizada em 76 pontos nos quais se determinou a distribuição de agregados por via úmida, usando água, álcool e benzeno como pré-tratamentos. Pelo exame de semivariogramas, constatou-se a ocorrência de dependência espacial. A krigagem ordinária foi usada como interpolador e mapas de contorno mostraram-se de grande utilidade na descrição da variabilidade espacial de agregação do solo. This work explored the applicability of the fractal theory for studies into space variability of soil aggregation. Fractal geometry has become a model for soil size particle distribution. The distribution of soil aggregates in terms of its mass was obtained, and model parameters such as the fractal dimension D, which is a representative measure of the soil fragmentation (the larger its value, the larger the fragmentation), and the largest aggregate size R L were defined as descriptive tools for soil aggregation. The aggregates were collected at a depth of 0-10 cm of a Clayey Ferrasol in Angatuba, São Paulo. A regular grid of 100 x 100 m was used and samples collected from 76 points, where the aggregate distribution was determined by humid way (water, alcohol and benzene). Spatial dependence was verified by semivariogram exams. Simple kriging was used as interpolator, and contour maps were elaborated, proving to be useful tools to describe the spatial variability of soil aggregation.

Agricultural management with chemicals may contaminate the soil with heavy metals. The objective of this study was to apply Principal Component Analysis and geoprocessing techniques to identify the origin of the metals Cu, Fe, Mn, Zn, Ni, Pb, Cr and Cd as potential contaminants of agricultural soils. The study was developed in an area of vineyard cultivation in the State of São Paulo, Brazil. Soil samples were collected and GPS located under different uses and coverings. The metal concentrations in the soils were determined using the DTPA method. The Cu and Zn content was considered high in most of the samples, and was larger in the areas cultivated with vineyards that had been under the application of fungicides for several decades. The concentrations of Cu and Zn were correlated. The geoprocessing techniques and the Principal Component Analysis confirmed the enrichment of the soil with Cu and Zn because of the use and management of the vineyards with chemicals in the preceding decades. O manejo agrícola com agroquímicos pode levar a contaminação dos solos por metais pesados. O objetivo deste trabalho foi aplicar a Análise dos Componentes Principais e técnicas de geoprocessamento para identificar a origem dos metais pesados Cu, Fe, Mn, Zn, Ni, Pb, Cr e Cd como contaminantes potenciais em solos agrícolas. O estudo foi desenvolvido em uma área cultivada com vinhedos no Estado de São Paulo, Brazil. Amostras de solos foram coletadas e georeferenciadas por GPS sob diferentes usos e coberturas. As concentrações dos metais nos solos foram obtidas pelo método de extração com DTPA. As concentrações de Cu e Zn foram consideradas altas na maioria das amostras pesquisadas, sendo maiores nas áreas cultivadas com vinhedos sob aplicações de fungicidas por décadas. As concentrações de Cu e Zn apresentaram correlação. As técnicas de geoprocessamento e a Análise dos Componentes Principais indicaram enriquecimento do solo com Cu e Zn devido ao uso e manejo dos vinhedos com agroquímicos nas décadas anteriores.

The objective of this work was to present the Analysis of Correspondence as a multivariate statistical method that can help in the yield mapping comparison. There is a concern about its indiscriminate use as tool of predictive information, without taking into consideration the spatial and temporal variability of the yield. The idea that the use of yield mapping is strictly related to the variability of the components was verified. Four yield maps were used corresponding to collected yield samples for rice in 1994, corn in 1995, cotton in 1996 and corn in 1998, in a grid with 110 points, spaced of 10 x 10 m, at the experimental station of the Agronomic Institute, located at Votuporanga, SP, Brazil. The original data were transformed using its order and analyzed using Simple and Multiple Correspondence Analysis. A great dissimilarity between the variables or classes of variables was found as measured by the Euclidean Distance in the plan.

O objetivo deste trabalho foi quantificar a contribuição da variável auxiliar altitude, na estimativa da distribuição espacial da precipitação anual média no Estado de São Paulo. A estatística quadrado médio do erro (QME) foi usada em dois conjuntos de observações de precipitação anual média (1957 a 1997): o completo, com 1.027 observações, e o reduzido, com 445. Bolsões de precipitação foram perfeitamente definidos nos mapas de variabilidade espacial que utilizaram o conjunto completo de dados, e indicaram a existência de possíveis microclimas. O interpolador geoestatístico de krigagem ordinária apresentou desempenho 82 vezes mais preciso que o interpolador do inverso do quadrado da distância, quando o QME foi usado como critério de comparação para o conjunto de dados completo. Para o conjunto reduzido, essa magnitude foi de duas vezes. Os erros de estimação obtidos por krigagem ordinária foram menores no conjunto completo, enquanto os obtidos por cokrigagem ordinária foram menores no reduzido. Isso indica que esses interpoladores devem ser usados para determinação da distribuição espacial da precipitação anual média. O uso da altitude como variável auxiliar beneficia o interpolador de cokrigagem ordinária e define microrregiões mais uniformes quanto à distribuição espacial da precipitação anual média. The objective of this work was to quantify the contribution of the auxiliary variable elevation in the estimate of the spatial distribution of annual average rainfall in the state of São Paulo, Brazil. The statistic mean square error (MSQR) was used in two observation sets for the mean annual rainfall (1957 to 1997): a full set, with 1,027 observations, and a reduced one, with 445. Areas of rainfall concentration were clearly defined in spatial variability maps that used the full data set, indicating possible microclimates. Ordinary kriging geostatistical interpolation had a performance 82 times more accurate than that of interpolation by the inverse square of the distance when the MSQR was used as a benchmark for the full set. For the reduced set, this magnitude was of two times. The estimation errors obtained by ordinary kriging were lower in the full set, whereas those obtained by ordinary cokriging were lower in the reduced one. This indicates that these interpolators should be used for determining the spatial distribution of annual average rainfall. The use of altitude as an auxiliary variable benefits the ordinary cokriging interpolator and defines more uniform micro regions as to the spatial distribution of annual average rainfall.

The use of geostatistics requires at least that the intrinsic hypothesis be satisfied. The presence of a trend in the data invalidates this hypothesis. One of the ways of solving this problem is by subtracting a function fitted to the original data and working with the residuals. This technique also represents a change to a smaller scale of the variability and surface roughness. This paper describes the detrending technique of subtracting a trend surface fitted by the least squares method and discusses the results using topographical data as examples. The objective is to show how the detrending technique works for different scales and degrees of trend and how to interpret the results. It is shown that the simplest the surfaces fitted that does the work of removing the trend the best are the results obtained. The use of jack knifing is proved useful to validate the resulting semivariograms. For most of the applications and depending upon the scale, a linear or a parabolic surface works reasonably well. The back transformation of the data afterwards is very easily done by adding back the subtracted trend surface. O uso de geoestatistica exige que pelo menos a hipótese intrínseca seja satisfeita. A presença de tendência invalida esta hipótese. Uma das maneiras mais práticas de resolver esta questão é subtrair dos dados originais uma função ajustada por mínimos quadrados, trabalhando com a função residual resultante. Esta técnica representa uma mudança de escala da variabilidade e da rugosidade da superfície para uma escala menor. Este trabalho descreve a técnica da remoção da tendência pela subtração de uma superfície ajustada por mínimos quadrados e discute os resultados usando dados topográficos como exemplos. O objetivo é mostrar como usar esta técnica para remover tendências de superfícies de diferentes escalas e com diferentes graus de superfície e como interpretar os resultados. Foi mostrado que quanto mais simples for a superfície ajustada que resolve o problema de tendência, melhores são os resultados obtidos. O uso da validação cruzada provou ser útil para validar os semivariogramas resultantes. Para a maioria das aplicações e dependendo da escala, uma superfície linear ou parabólica funciona muito bem. A transformação de retorno nos dados é bastante fácil e é feita somando de volta a superfície subtraída.

Comumente dados de precipitação pluvial apresentam variação e a obtenção da estimativa de sua distribuição espacial é primordial no planejamento agrícola e ambiental. O objetivo neste trabalho foi comparar o método de estimação dos mínimos quadrados ponderados para ajuste de modelos ao semivariograma com o método de tentativa e erro, através da técnica de auto-validação "jack-knifing", para dados de precipitação pluvial média anual do Estado de São Paulo. Observações de precipitação correspondentes ao período de 1957 a 1997 foram usadas para trezentos e setenta e nove (379) estações pluviométricas abrangendo todo o Estado de São Paulo, representando uma área de aproximadamente 248.808,8 km². A periodicidade exibida pelos semivariogramas foi ajustada pelo modelo "hole effect", em que os parâmetros foram estimados com maior precisão pelo método de mínimos quadrados ponderados quando comparado com o método de tentativa e erro. O método de auto-validação "jack-knifing" mostrou-se adequado para a definição de métodos e modelos a serem usados para semivariâncias, cujo procedimento permitiu definir dezesseis vizinhos como o número ideal para a estimativa por krigagem de valores de precipitação pluvial para locais não amostrados no Estado de São Paulo.

O objetivo do presente trabalho foi apresentar a Análise de Correspondência como um método estatístico multivariado que pode ajudar na interpretação de mapas de produtividade. Para tal, levantou-se a hipótese de a utilização de mapas de produtividade, para delimitar regiões homogêneas no campo, depender da estabilidade espacial e temporal desta variável, tornando-se preocupante seu uso indiscriminado como ferramenta de informação preditiva. Quatro mapas de produtividade foram usados neste trabalho, relativos a amostras coletadas de componentes de produção para arroz em 1994, milho em 1995, algodão em 1996 e milho em 1998, em uma malha com 110 pontos, espaçados de 10 x 10 m, da estação experimental do Instituto Agronômico de Campinas em Votuporanga (SP). Os dados originais de produtividade foram categorizados e analisados por meio da Análise de Correspondência Simples e Múltipla. Concluiu-se que existe grande dissimilaridade entre as culturas, ou classes de culturas, medidas por meio da distância euclidiana no plano. The objective of this work was to present the Analysis of Correspondence as a multivariate statistical method that can help with yield mapping interpretation. There is a concern about its indiscriminated use as a tool of predictive information, without taking into account the spatial and temporal variability of the yield. The hypothesis that the use of yield mapping is strictly related to the variability of the components was studied. Four yield maps were used corresponding to collected yield samples for rice in 1994, corn in 1995, cotton in 1996 and corn in 1998, in a grid of 110 points, 10 x 10 m spaced, at the experimental station of the Instituto Agronômico, at Votuporanga (SP), Brazil. The original yield data were categorised and analyzed using Simple and Multiple Correspondence Analysis. A great dissimilarity between the cultures or classes of cultures was found as measured by the Euclidean Distance in the plan.

A Experimentação Agronômica apresenta-se como uma técnica difícil e perigosa. principalmente quando se quer tornar decisões a respeito do melhor procedimento a ser empregado. O presente trabalho tem por objetivo uma introdução à análise sequencial. especificamente ao teste t-sequencial; verificar seu poder e sua robustez quando comparado com um teste equivalente não-sequencial. Tal comparação é feita através da técnica de simulação de dados, obtendo resultados que mostram, quando bem utilizada. quão eficiente e o seu emprego. O número de observações e função de uma sequencial finita de dados com probabilidade igual a 1 de se tomar uma decisão. ou seja, aceitar ou rejeitar a hipótese H0 : = 0 em favor da hipótese H1 : = . Os dados são simulados através da sub-rotina UNNOR (Apêndice I), com distribuição Normal de média e variância 2. Para os riscos fixados , obtêm-se, para cada caso. o número de rejeições, não-rejeições da hipótese de nulidade, além da esperança e variância de N. O cálculo do número médio de observações para o teste t-sequencial é feito com o intuito de comparar. sob determinadas hipóteses, com o número de observações para o teste t de Student, verificando-se que, em média, necessita-se de menor número de observações para o teste sequencial. Quando a hipótese alternativa está próxima da hipótese de nulidade, verifica-se pelo atual estudo que o número de observações requerido pelo teste sequencial é, em média, a metade do requerido pelo teste de Student, sendo por isso condizentes com os resultados apresentados pela literatura tradicional. A medida em que a hipótese alternativa se afasta da nulidade, a relação entre o número de observações apresentado pelos testes vai diminuindo, chegando em alternativas mais afastadas, até a se igualar. O poder para os testes é calculado, e observa-se que, em média, para o teste t-sequencial, em todos os casos estudados.se apresenta maior. A probabilidade de se estar cometendo um erro quando faz-se a afirmação de que o poder é maior para o teste sequencial é calculada para cada caso, encontrando-se a maior probabilidade igual a 16,80%, sendo por isso possível tal afirmação. É apresentado o gráfico da Curva Característica de Operação e do Tamanho Médio de Amostras para = 1,00. Além do mais, verifica-se pelo trabalho, que o estudo sobre a não-normalidade dos dados. permite a conclusão de que o teste t-sequencial independe dos princípios para o qual é formado, caracterizando dessa forma sua robustez. Agronomic Experimentation is a difficult and dangerous technique especially when one wants to make about decisions bettering his rnethod to be utilized in his work. The present work has as an objective the introduction to Sequential Analysis specifically to the Sequential t-test in respect to its power and robustness when compareci with another equivalent test which is not sequential. Such a comparison is dane by a data simulation technique thus getting results which when well utilized are very efficient for the purpose. The number of observations is a function of one infinite sequence of data with a probability equal to 1 to get to a decision whether to accept or reject the hypothesis H0 : = 0 in favor of H1 : = . Data are simulated by the sub-routine UNNOR (Appendix with a Normal distribution of average and variance 2. For the fixed risks a number of rejections are obtained for each case, non-rejections of the nullity hypothesis inspite of the expectation and variance of N. The calculations of the average number of observations for the sequential t-test are dane with the intention of comparing with a number of observations for the Student t-test, thus verifyng that on the average fewer observations are necessary for the sequential test. When an alternativa hypothesis is close to the null hypothesis, it is verified in this work that the number of observa- tions required by the sequential test is, on the average, half of that required by the Student t-test, thus agreeing with the results presented by the traditional literatura. From the way by which the alternative hypothesis is itself distant from nullity the relation between the number of observations presented by the tests keeps decreasing to wards distant alternativas until they equalise themselves. The power for the tests is calculated and in all the cases studied of the sequential t-tests, it is more on the average. An estimate of the probability of deciding upon the more powerfull test (Sequential or non-sequential) wrongly is obtained and a result as high as 16,80% is gotten in the worst condition. The Power Function and the Average Sample Size for = 1,00 are presented in graphs. Along witer other conclusions reached_ the present work verifies that the non-normality study of data allows the conclusion that sequential t-test is not strongly affected by the principles for which it was formed; thus characterising move, in this way, its robustness.

Um novo método para avaliação do tamanho de gotas de chuva e sua distribuição é apresentado. O método é baseado no processamento de imagens com o uso da transformada de Hough circular em conjunto com as técnicas de Backmapping e análise de vizinhança. Esta metodologia trás vantagens, uma vez que viabiliza medidas diretas e de forma automática para identificação e contagem de gotas de chuva. A calibração do método foi desenvolvida utilizando padrões de gotas conhecidos. Gotas, na faixa de 1 &#956m a 85 mm de diâmetro, foram automaticamente reconhecidas e medidas com sucesso. Resultados mostram erro médio percentual não maior que 3,61%. Adicionalmente é apresentado uma comparação de resultados obtidos com um método de análise de correlação em frequência e contagem direta. Resultados mostram a potencialidade da metodologia desenvolvida para aplicações agrícolas. A new method for evaluating raindrop size and distribution has been developed. It is based on image processing with circular Hough fast transform composed with the Backmapping and neighborhood analysis techniques. This methodology has the advantage of being a direct measurement method that automatically identifies and counts raindrops. Calibration was carried out using standard patterns with known raindrop sizes. Drops sizes ranging from 1 &#956m sizes to 85 mm in diameter has been automatically recognized and successfully measured. Results show perceptual average error not larger than 3,61%. In addition a comparison of results with the correlation analysis in the frequency domain and directed counts methods are presented. Results show the suitability of developed methodology.

Mobile learning is the kind of learning that applies mainly to non-formal education actions from the perspective of continuing education. Within the scope of companies, the demand for educational actions is increasing, notably focused on distance education and training, aimed at both internal and external audiences. However, for the implementation of activities dedicated to mobile learning, it is necessary to develop a digital platform to host the virtual learning environment. Under these conditions, it should be structured in a flexible format and design to encourage interactivity between learners and teachers in the implementation of teaching and learning activities. The article presents and discusses a proposal for a digital mobile platform, called e-Códex, which aims to support educational actions, to promote collaboration and learning, as well as to meet the information dissemination and knowledge generation needs of the Brazilian agroforestry sector.

Resumo - O objetivo deste trabalho foi quantificar a contribuição da variável auxiliar altitude, na estimativa da distribuição espacial da precipitação anual média no Estado de São Paulo. A estatística quadrado médio do erro (QME) foi usada em dois conjuntos de observações de precipitação anual média (1957 a 1997): o completo, com 1.027 observações, e o reduzido, com 445. Bolsões de precipitação foram perfeitamente definidos nos mapas de variabilidade espacial que utilizaram o conjunto completo de dados, e indicaram a existência de possíveis microclimas. O interpolador geoestatístico de krigagem ordinária apresentou desempenho 82 vezes mais preciso que o interpolador do inverso do quadrado da distância, quando o QME foi usado como critério de comparação para o conjunto de dados completo. Para o conjunto reduzido, essa magnitude foi de duas vezes. Os erros de estimação obtidos por krigagem ordinária foram menores no conjunto completo, enquanto os obtidos por cokrigagem ordinária foram menores no reduzido. Isso indica que esses interpoladores devem ser usados para determinação da distribuição espacial da precipitação anual média. O uso da altitude como variável auxiliar beneficia o interpolador de cokrigagem ordinária e define microrregiões mais uniformes quanto à distribuição espacial da precipitação anual média.

Angular leaf spot, incited by Isariopsis griseola Sacc., has become one of the most important diseases of dry beans in Brazil. In the past, it was considered to be a disease of minor importance due to its low incidence and late appearance in the growing season. However, these facts have changed and angular leaf spot has cause severe yield losses in some bean production areas. This study was conducted during 1981-83 at Centro Nacional de Pesquisa de Arroz e Feijão in order to assess yield losses in dry beans caused by this disease.