TOWARDS LIFELONG CROP RECOGNITION USING FULLY CONVOLUTIONAL RECURRENT NETWORKS AND SAR IMAGE SEQUENCES

Abstract. Recent works have studied crop recognition in regions with highly complex spatio-temporal dynamics typical of a tropical climate. However, most proposals have only been evaluated in a single agricultural year, and their capabilities to generalize to dates outside the temporal sequence have not been properly addressed thus far. This work assesses the generalization capabilities of a recent convolutional recurrent architecture, testing it in a temporal sequence two years ahead of the sequence with which it was trained. Furthermore, a N-to-1 variant of such network is proposed, which is able to produce classification outcomes for every month in the agricultural year, and it is compared with two baselines designed in a more traditional approach, in which a separate specific network is trained for each month of the year. The approaches are evaluated on two public datasets from a tropical region. The first dataset comprehends the period from June 2017 to May 2018, while the second goes from October 2019 to September 2020. Results show a decrease of up to 24.6% in per-date average F1 score when training the network with data of an agricultural year different from the one it is tested on, which indicates a domain shift that demands further research. Additionally, the proposed approach presented only a slight decrease in performance compared to its baseline when trained on the same dataset, with a 2.7% drop in average F1 score. This performance drop is a small cost in exchange for its operational advantages, such as reduced training time and a more straightforward pipeline.

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COMPORTAMENTO ESPAÇO-TEMPORAL DA FUSARIOSE EM PIMENTA-DO-REINO

Nativa ◽

10.31413/nativa.v7i5.7261 ◽

2019 ◽

Vol 7 (5) ◽

pp. 484

Author(s):

Ana Carolina Lyra Brumat ◽

Marcelo Silva ◽

Antonio Fernando de Souza ◽

Ivoney Gontijo ◽

Edney Leandro da Vitória ◽

...

Keyword(s):

Fusarium Solani ◽

Temporal Dynamics ◽

Temporal Distribution ◽

Black Pepper ◽

Piper Nigrum ◽

Progress Curve ◽

Taylor’S Law ◽

Spatio Temporal ◽

The One ◽

Best Fit

Objetivou-se com o trabalho estudar a dinâmica de distribuição espaço-temporal da fusariose em pimenta-do-reino. Foram monitoradas quatro áreas de plantio, no município de São Mateus-ES, no período de dez/2015 a dez/2016. Realizaram-se seis avaliações da doença. As plantas foram avaliadas visualmente em busca dos sintomas típicos da doença. A presença ou ausência de sintomas, e a posição de cada planta, foram anotadas em planilhas obtendo-se o mapeamento da evolução da doença dentro das áreas. Com base nos mapas criados fez-se o estudo da distribuição espaço-temporal. A partir dos dados de incidência calculou-se a área abaixo da curva de progresso da doença (AACPD) e realizou-se o ajuste de modelos epidemiológicos. Para o estudo espacial utilizou-se a Lei de Taylor modificada, o Índice de Dispersão (ID) e a análise de dinâmica e estrutura de focos (ADEF). O modelo monomolecular foi o que melhor se ajustou à curva de progresso da fusariose. Observou-se que os resultados de ID variaram em cada área. A Lei de Taylor modificada indicou distribuição agregada somente em uma área. A ADEF demonstrou que com a evolução da doença ao longo do tempo os focos se tornavam maiores e em menor número.Palavras-chave: Piper nigrum; Fusarium solani f. sp. piperis; epidemiologia. SPATIO-TEMPORAL BEHAVIOR OF FUSARIOSIS IN BLACK PEPPER ABSTRACT: The objective of this study was to study the spatio-temporal dynamics of fusariosis in black pepper. Four planting areas were monitored in the municipality of São Mateus-ES, in the period from 10/2015 to 10 / 2016. Six classifieds of the disease were carried out. The plants were visually evaluated for the typical symptoms of the disease. The presence or absence of symptoms, and the position of each plant, were recorded on planets and the mapping of the evolution of the disease within the areas was obtained. Based on the sites visited, he studied the spatial-temporal distribution. From the calculation data, an area under the disease progress curve (AACPD) is calculated and adjusted for epidemiological models. For the spatial study we used a modified Taylor's Law, the Dispersion Index (ID) and a dynamics and foci structure analysis (ADEF). The monomolecular model was the one that best fit the progression curve of fusariosis. It was observed that the ID results varied in each area. The modified Taylor Law indicated the distribution of content in an area. ADEF demonstrated an evolution of the disease over time as the outbreaks became larger and smaller.Keywords: Piper nigrum; Fusarium solani f. sp. piperis; epidemiology.

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Uncovering the organization of neural circuits with generalized phase locking analysis

10.1101/2020.12.09.413401 ◽

2020 ◽

Author(s):

Shervin Safavi ◽

Theofanis Panagiotaropoulos ◽

Vishal Kapoor ◽

Juan F. Ramirez-Villegas ◽

Nikos K. Logothetis ◽

...

Keyword(s):

Neural Circuits ◽

Temporal Dynamics ◽

Phase Locking ◽

Network Models ◽

Field Coupling ◽

Neural Ensembles ◽

Field Activity ◽

Spatio Temporal ◽

The One

AbstractSpike-field coupling characterizes the relationship between neurophysiological activities observed at two different scales: on the one hand, the action potential produced by a neuron, on the other hand a mesoscopic “field” signal, reflecting subthreshold activities. This provides insights about the role of a specific unit in network dynamics. However, assessing the overall organization of neural circuits based on multivariate data requires going beyond pairwise approaches, and remains largely unaddressed. We develop Generalized Phase Locking Analysis (GPLA) as an multichannel extension of univariate spike-field coupling. GPLA estimates the dominant spatio-temporal distributions of field activity and neural ensembles, and the strength of the coupling between them. We demonstrate the statistical benefits and interpretability of this approach in various biophysical neuronal network models and Utah array recordings. In particular, we show that GPLA, combined with neural field modeling, help untangle the contribution of recurrent interactions to the spatio-temporal dynamics observed in multi-channel recordings.

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ANOMALOUS PERCEPTION OF BIOLOGICAL MOTION IN AUTISM: A CONCEPTUAL REVIEW AND META-ANALYSIS

10.1101/530030 ◽

2019 ◽

Cited By ~ 1

Author(s):

Alessandra Federici ◽

Valentina Parma ◽

Michele Vicovaro ◽

Luca Radassao ◽

Luca Casartelli ◽

...

Keyword(s):

Autism Spectrum Disorder ◽

Biological Motion ◽

Temporal Dynamics ◽

Traditional Approach ◽

Meta Analysis ◽

Autism Spectrum ◽

Spectrum Disorder ◽

Wide Range ◽

Spatio Temporal ◽

Meta Analyses

AbstractDespite its popularity, the construct of biological motion (BM) and its putative anomalies in autism spectrum disorder (ASD) are not completely clarified. Here, we propose a new model describing distinct levels of BM processing, and we present a meta-analysis investigating BM perception in ASD. We screened 114 articles testing BM perception in ASD and typical developing peers. A general meta-analysis including all the selected studies (N=27) showed BM processing moderate deficit in ASD, but high heterogeneity. This heterogeneity was explored in different additional meta-analyses where studies were grouped according to different levels of BM processing (first-order/direct/instrumental) and the manipulation of low-level perceptual features (spatial/temporal). Results suggest that the most severe deficit in ASD is evident when perception of BM is serving a secondary purpose (e.g., inferring intentionality/action/emotion) and, interestingly, that temporal dynamics could be an important factor in determining BM processing anomalies in ASD. In conclusion, this work questions the traditional understanding of BM anomalies in ASD and claims for a paradigm shift that deconstructs BM into distinct levels of processing and specific spatio-temporal subcomponents.Public Significance statementSince the seminal study by Johansson (1973), the construct of “biological motion” (BM) has gained a considerable success in a wide range of disciplines. In particular, BM processing has been considered a putative marker for social difficulties in neurodevelopmental conditions such as autism spectrum disorder (ASD). Our work aims to quantitatively test the solidity of this view through a meta-analytic approach and also to better define anomalies in BM perception according to distinct levels of complexity and specific spatio-temporal features. Interestingly, we do it by challenging the traditional approach to the conception of BM. This novel conceptualization has intriguing clinical and theoretical insights.

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Nonlinear Spatio-Temporal Dynamics and Chaos in Semiconductors

10.1017/cbo9780511524615 ◽

2001 ◽

Cited By ~ 136

Author(s):

Eckehard Schöll

Keyword(s):

Temporal Dynamics ◽

Spatio Temporal

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Spatio-temporal dynamics of ascidian larval recruitment and colony abundance in a non-indigenous Newfoundland population

Marine Ecology Progress Series ◽

10.3354/meps12437 ◽

2017 ◽

Vol 585 ◽

pp. 99-112 ◽

Cited By ~ 2

Author(s):

KCK Ma ◽

D Deibel ◽

JB Lowen ◽

CH McKenzie

Keyword(s):

Temporal Dynamics ◽

Larval Recruitment ◽

Spatio Temporal

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Spatial and temporal dynamics of Pacific capelin Mallotus catervarius in the Gulf of Alaska: implications for ecosystem-based fisheries management

Marine Ecology Progress Series ◽

10.3354/meps13211 ◽

2020 ◽

Vol 637 ◽

pp. 117-140 ◽

Cited By ~ 1

Author(s):

DW McGowan ◽

ED Goldstein ◽

ML Arimitsu ◽

AL Deary ◽

O Ormseth ◽

...

Keyword(s):

Temporal Dynamics ◽

Marine Ecosystem ◽

Gulf Of Alaska ◽

Data Series ◽

Limited Information ◽

Important Species ◽

Multiple Data ◽

Spatial And Temporal Dynamics ◽

Spawning Areas ◽

Spatio Temporal

Pacific capelin Mallotus catervarius are planktivorous small pelagic fish that serve an intermediate trophic role in marine food webs. Due to the lack of a directed fishery or monitoring of capelin in the Northeast Pacific, limited information is available on their distribution and abundance, and how spatio-temporal fluctuations in capelin density affect their availability as prey. To provide information on life history, spatial patterns, and population dynamics of capelin in the Gulf of Alaska (GOA), we modeled distributions of spawning habitat and larval dispersal, and synthesized spatially indexed data from multiple independent sources from 1996 to 2016. Potential capelin spawning areas were broadly distributed across the GOA. Models of larval drift show the GOA’s advective circulation patterns disperse capelin larvae over the continental shelf and upper slope, indicating potential connections between spawning areas and observed offshore distributions that are influenced by the location and timing of spawning. Spatial overlap in composite distributions of larval and age-1+ fish was used to identify core areas where capelin consistently occur and concentrate. Capelin primarily occupy shelf waters near the Kodiak Archipelago, and are patchily distributed across the GOA shelf and inshore waters. Interannual variations in abundance along with spatio-temporal differences in density indicate that the availability of capelin to predators and monitoring surveys is highly variable in the GOA. We demonstrate that the limitations of individual data series can be compensated for by integrating multiple data sources to monitor fluctuations in distributions and abundance trends of an ecologically important species across a large marine ecosystem.

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