Primes in arithmetic progressions and semidefinite programming

Assuming the generalized Riemann hypothesis, we give asymptotic bounds on the size of intervals that contain primes from a given arithmetic progression using the approach developed by Carneiro, Milinovich and Soundararajan [Comment. Math. Helv. 94, no. 3 (2019)]. For this we extend the Guinand-Weil explicit formula over all Dirichlet characters modulo $q \geq 3$, and we reduce the associated extremal problems to convex optimization problems that can be solved numerically via semidefinite programming.Comment: 11 pages, 5 ancillary file

Transformation of UML Behavioral Diagrams to Support Software Model Checking

Unified Modeling Language (UML) is currently accepted as the standard for modeling (object-oriented) software, and its use is increasing in the aerospace industry. Verification and Validation of complex software developed according to UML is not trivial due to complexity of the software itself, and the several different UML models/diagrams that can be used to model behavior and structure of the software. This paper presents an approach to transform up to three different UML behavioral diagrams (sequence, behavioral state machines, and activity) into a single Transition System to support Model Checking of software developed in accordance with UML. In our approach, properties are formalized based on use case descriptions. The transformation is done for the NuSMV model checker, but we see the possibility in using other model checkers, such as SPIN. The main contribution of our work is the transformation of a non-formal language (UML) to a formal language (language of the NuSMV model checker) towards a greater adoption in practice of formal methods in software development.Comment: In Proceedings FESCA 2014, arXiv:1404.043

Analysis of the pedagogical perspective of the MOOCs available in Portuguese

After an initial stage of exponential growth in MOOCs, a need has arisen of to address several different aspects of these innovations in order to understand and develop them from different perspectives, such as this one, with the analysis of pedagogical dimensions aimed at improving course design. This paper presents an updated review of the literature and proposes five research lines for an in-depth approach. This study is part of a broader research project1 and here analyses 356 MOOCs delivered in Portuguese by 16 different platforms. The research design is quantitative, non-experimental and transversal. An adaptation of the MOOC Educational and Interactive Indicators Instrument —INdiMOOC-EdI— was used in the data collection process. The reliability and internal consistency analysis of that adaptation for the whole sample resulted in a Cronbach alpha score of 0.731. The data obtained enable us to classify the existing MOOCs in Portuguese according to descriptive, formative, and interactive components. These different types correlate with the quality indices, being negative in the first dimension (descriptive) and positive in the second and third ones (formative and interactive).Funded by the call for R&D&i projects named: «Estudio del impacto de las erubricas federada en evaluación de las competencias en el practicum» (Study on the impact of federated eRubrics in the evaluation of the competences in the practicum). Plan Nacional de I+D+i de Excelencia (National R&D&i Excellence Plan) (2014-16) no. EDU2013-41974-

MODIS NDVI, EVI and NDWI time series for cotton phenological characterization

O desenvolvimento e a competitividade do setor agrícola brasileiro estão atrelados aos avanços tecnológicos e eficiência na alocação dos recursos. A utilização de dados de sensores orbitais destaca-se como ferramenta para o acompanhamento dos cultivos, a avaliação dos sistemas de produção e a previsão de safra. Esse potencial dos sensores orbitais foi impulsionado pelos avanços da resolução temporal, destacando-se o sensor Moderate Imaging Spectroradiometer (MODIS). O presente trabalho teve como objetivo caracterizar os estádios fenológicos do algodão no Cerrado utilizando séries temporais de NDVI, EVI e NDWI do sensor MODIS. A utilização efetiva dessas séries temporais mostra-se dependente do tratamento dos ruídos. O emprego conjunto do filtro de mediana e da transformação inversa da Fração Mínima de Ruído (FMR) apresentou-se como eficiente alternativa para o tratamento dos ruídos. Os comportamentos médios anuais de NDVI, EVI e NDWI evidenciam uma variação sazonal que caracterizam os estágios fenológicos da cultura do algodão. ____________________________________________________________________________________ ABSTRACTThe development and competitiveness of the Brazilian agricultural sector are coupled to technological advances and efficiency in resource allocation. The use of orbital sensor data stands as an important tool for the crops monitoring, production system evaluation and forecasting. This potential was driven by the improving of the temporal resolution specially the Moderate Imaging Spectroradiometer (MODIS). This work aimed to characterize the phenological stages of cotton in the Cerrado biome using MODIS NDVI, EVI and NDWI time series. However, the effective utilization of this time series is dependent of the noise reduction. The employment of the median filter and inverse transformation of Minimum Noise Fraction (MNF) proved to be efficient as noise reduction procedures. The annual average temporal behavior of NDVI, EVI and NDWI show a seasonal variation that characterizes the phenological stages of the cotton crops. Beyond this phenological characterization, the procedures presented can support the regional production arrangements, energetic fluxes monitoring and evaluation of production system efficiency

Modis time series applied to crop succession of soybean (Glycine max (L.) Merril) and maize (Zea mays L.) in no-tillage system

Os sensores orbitais com alta resolução temporal proporcionam identificar as etapas fenológicas dos cultivos agrícolas. O presente artigo teve como objetivo analisar séries temporais do sensor Moderate Imaging Spectroradiometer (MODIS) para a descrição das sucessões soja-milho e milho-soja em sistema de plantio direto. As imagens utilizadas são os produtos de reflectância de superfície composição de oito dias (MOD09), contendo sete bandassobre um período de 12 anos (200-2011). A metodologia adotada pode ser subdividida nas seguintes etapas: (a) eliminação dos ruídos das séries temporais a partir da combinação do filtro de mediana com a Fração Mínima de Ruido (FMR), (c) elaboração dos índices de vegetação Normalized Difference Vegetation Index (NDVI); Enhanced Vegetation Index (EVI) e Normalized Difference Water Index (NDWI); (c) análise estatística com o propósito de identificar a correspondência das séries temporais com as fases de sucessão de culturas soja e milho. Os dados temporais NDVI, EVI, e NDWI apresentam respostas sazonais para o cultivo de sucessão de milho-soja e soja-milho, mostrando-se consistentes com a fenologia das culturas. Os perfis temporais tratados evidenciaram os comportamentos ao longo do tempo, sendo que a soja como primeira cultura apresentou maiores valores para todos os índices avaliados. A soja apresentou em média um ciclo de 143 dias, com início da semeadura em 23 de outubro. O ciclo produtivo médio do milho como cultura principal foi 127 dias, com início em 08 de novembro. _________________________________________________________________________________ ABSTRACTThe orbital sensors with high temporal resolution allowed improvements in the phonological stages characterization. This paper aimed to analyze time series from Moderate Imaging Spectroradiometer (MODIS) sensor for the soybeancorn and corn-soybean succession in no-tillage system. The images used are the MODIS surface reflectance 8-day composite products (MOD09), containing seven-band over a 12-year period (2000-2011). The methodology can be subdivided into the following steps: (a) noise elimination of time series combining the median filter with a Minimum Noise Fraction (MNF); (c) application of vegetation indices: Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI) and Normalized Difference Water Index (NDWI); and (c) statistical analysis in order to identify the correspondence of the time series with the phases of crop rotation soybeans and corn. EVI, NDVI and NDWI temporal profiles show seasonal responses to crop succession of corn-soybeans and soybeans- corn. Temporal signatures were consistent with the general phenological characteristics. The smoothed temporal profiles evidenced the behavior through the time and that the soybean as first crop showed the highest values for all vegetation indices evaluated. The soybean had an average 143-days cycle, beginning in October 23th. The average productive cycles of the maize as main crop were 127-days, starting in November 8th

Food as a human right: combatting global hunger and forging a path to food sovereignty. Schanbacher, WD. Santa Barbara: Praeger, 2019. 212p. (Series: Praeger Security International), ISBN: 978-1-4408-6177-2.

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