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1.
Data Brief ; 49: 109385, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37520643

ABSTRACT

Visual tracking of objects is a fundamental technology for industry 4.0, allowing the integration of digital content and real-world objects. The industrial operation known as manual cargo packing can benefit from the visual tracking of objects. No dataset exists to evaluate the visual tracking algorithms on manual packing scenarios. To close this gap, this article presents 6D-ViCuT, a dataset of images, and 6D pose ground truth of cuboids in a manual packing operation in intralogistics. The initial release of the dataset comprehends 28 sessions acquired in a space that rebuilds a manual packing zone: indoors, area of (6 × 4 × 2) m3, and warehouse illumination. The data acquisition experiment involves capturing images from fixed and mobile RGBD devices and a motion capture system while an operator performs a manual packing operation. Each session contains between 6 and 18 boxes from an available set of 10 types, with each type varying in height, width, depth, and texture. Each session had a duration in the range of 1 to 5 minutes. Each session exhibits operator speed and box type differences (box texture, size heterogeneity, occlusion).

2.
Found Sci ; : 1-28, 2022 Sep 28.
Article in English | MEDLINE | ID: mdl-36187324

ABSTRACT

This paper employs network theory, mining data and bibliometric analysis when mapping the scientific contribution of Nobel Prize candidate; Manuel Sandoval Vallarta, the first and most renowned Mexican physicist and important figure in Latin American science. Vallarta died in 1977, and the existing literature is about his life and contributions to science but not about how those are still valuable today. This paper is the first to highlight, with mapping tools, that his contributions are relevant to the international community of cosmic rays (as he was pioneer and leader), quantum mechanics and relativity. These tools delivered three findings: Identify how he built his own field of study, same as universal knowledge. Unveil that the backward and forward Vallarta citations follow a scale-free network distribution. Determine social factors that benefited or affected his scientific activities-such as World War II interrupting Vallarta's successful productivity at Massachusetts Institute of Technology. Furthermore, this study confirmed the interdisciplinary nature of the mapping studies of the scientist's contributions using scientometric tools. As a result, several interesting questions arose throughout our research, some of which were answered from the history and philosophy of science. However, others need to be analyzed by experts in the fields of Vallarta. Mapping research sends an invitation to interdisciplinary dialogue/research between experts in different areas of study to better understand the process of knowledge production both, individual and collective.

3.
Plants (Basel) ; 11(17)2022 Aug 25.
Article in English | MEDLINE | ID: mdl-36079580

ABSTRACT

Currently, there are no free databases of 3D point clouds and images for seedling phenotyping. Therefore, this paper describes a platform for seedling scanning using 3D Lidar with which a database was acquired for use in plant phenotyping research. In total, 362 maize seedlings were recorded using an RGB camera and a SICK LMS4121R-13000 laser scanner with angular resolutions of 45° and 0.5° respectively. The scanned plants are diverse, with seedling captures ranging from less than 10 cm to 40 cm, and ranging from 7 to 24 days after planting in different light conditions in an indoor setting. The point clouds were processed to remove noise and imperfections with a mean absolute precision error of 0.03 cm, synchronized with the images, and time-stamped. The database includes the raw and processed data and manually assigned stem and leaf labels. As an example of a database application, a Random Forest classifier was employed to identify seedling parts based on morphological descriptors, with an accuracy of 89.41%.

4.
Icarus ; 3732022 Feb.
Article in English | MEDLINE | ID: mdl-34916708

ABSTRACT

The deep convective cloud-environment feedback loop is likely important to Titan's global methane, energy, and momentum cycles, just as it is for Earth's global water, energy, and momentum budgets. General circulation models of Titan's atmosphere are unable to explicitly simulate deep convection and must instead parameterize the impact of this important subgrid-scale phenomenon on the model-resolved atmospheric state. The goal of this study is to better quantify through cloud resolving modeling the effects of deep convective methane storms on their environment and to feed that information forward to improve parameterizations in global models. Dozens of atmospheric profiles unstable with respect to deep moist convection are extracted from the global Titan Atmospheric Model (TAM) and used to initialize the cloud-resolving Titan Regional Atmospheric Modeling System (TRAMS). Mean profiles of heating/cooling and moistening/drying of the large-scale environment in TRAMS indicate that Titan's deep convection forces the environment in a manner analogous to Earth: Large-scale subsidence of the environmental air warms and dries the environment, but clouds can also moisten the environment through the detrainment and evaporation of condensate near cloud top. Relative humidity profiles and characteristic convective time scales are derived to guide the tuning of the deep convective parameterization implemented in TAM, as described in a companion paper. The triggering of convection, the dry convective mixing of the planetary boundary layer, and the entrainment of environmental air into rising air parcels are found to be critical to determining whether a deep convective cloud will form. Only profiles with relatively large convective available potential energy (CAPE) and well mixed planetary boundary layers with high relative humidity were found to produce storms. Environments with low level thermal inversions and planetary boundary layers with low relative humidity or rapidly decreasing moisture with height failed to generate deep convection in TRAMS despite positive CAPE.

5.
Plants (Basel) ; 10(12)2021 Dec 17.
Article in English | MEDLINE | ID: mdl-34961275

ABSTRACT

Growing evaluation in the early stages of crop development can be critical to eventual yield. Point clouds have been used for this purpose in tasks such as detection, characterization, phenotyping, and prediction on different crops with terrestrial mapping platforms based on laser scanning. 3D model generation requires the use of specialized measurement equipment, which limits access to this technology because of their complex and high cost, both hardware elements and data processing software. An unmanned 3D reconstruction mapping system of orchards or small crops has been developed to support the determination of morphological indices, allowing the individual calculation of the height and radius of the canopy of the trees to monitor plant growth. This paper presents the details on each development stage of a low-cost mapping system which integrates an Unmanned Ground Vehicle UGV and a 2D LiDAR to generate 3D point clouds. The sensing system for the data collection was developed from the design in mechanical, electronic, control, and software layers. The validation test was carried out on a citrus crop section by a comparison of distance and canopy height values obtained from our generated point cloud concerning the reference values obtained with a photogrammetry method. A 3D crop map was generated to provide a graphical view of the density of tree canopies in different sections which led to the determination of individual plant characteristics using a Python-assisted tool. Field evaluation results showed plant individual tree height and crown diameter with a root mean square error of around 30.8 and 45.7 cm between point cloud data and reference values.

6.
Sensors (Basel) ; 18(7)2018 Jul 16.
Article in English | MEDLINE | ID: mdl-30012990

ABSTRACT

Technological innovations in the hardware of RGB-D sensors have allowed the acquisition of 3D point clouds in real time. Consequently, various applications have arisen related to the 3D world, which are receiving increasing attention from researchers. Nevertheless, one of the main problems that remains is the demand for computationally intensive processing that required optimized approaches to deal with 3D vision modeling, especially when it is necessary to perform tasks in real time. A previously proposed multi-resolution 3D model known as foveated point clouds can be a possible solution to this problem. Nevertheless, this is a model limited to a single foveated structure with context dependent mobility. In this work, we propose a new solution for data reduction and feature detection using multifoveation in the point cloud. Nonetheless, the application of several foveated structures results in a considerable increase of processing since there are intersections between regions of distinct structures, which are processed multiple times. Towards solving this problem, the current proposal brings an approach that avoids the processing of redundant regions, which results in even more reduced processing time. Such approach can be used to identify objects in 3D point clouds, one of the key tasks for real-time applications as robotics vision, with efficient synchronization allowing the validation of the model and verification of its applicability in the context of computer vision. Experimental results demonstrate a performance gain of at least 27.21% in processing time while retaining the main features of the original, and maintaining the recognition quality rate in comparison with state-of-the-art 3D object recognition methods.

7.
Environ Sci Pollut Res Int ; 24(7): 6106-6113, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27094267

ABSTRACT

Worldwide, year by year, Fenton's Technologies have been highlighted in both academic and patent scopes, in part due to their proven efficiency as environment-friendly technologies destined to the abatement of organic pollutants, and also by their growing interest to produce industrial applications. Thus, aiming to understand the effective dynamic between two worlds, academy vs patents, the present study performs a comparative analysis about publications on Fenton-based Technologies (FbT). Therefore, in this work, technological foresight techniques were adopted focusing on patent and non-patent databases, employing for this, the Web of Science (WoS) database as a prospecting tool. The main results for the last decade point out to a strong increment of the Fenton's Technologies, as much in R&D as in patent applications in the world. Chinese Universities and firms command the scenario. There is an expressive gap between the academic and patent issues.


Subject(s)
Patents as Topic/statistics & numerical data , Technology/statistics & numerical data , Universities/statistics & numerical data , Brazil , China , Humans , Publications
8.
Proc Natl Acad Sci U S A ; 113(22): E3062-70, 2016 May 31.
Article in English | MEDLINE | ID: mdl-27185925

ABSTRACT

Trade wind regions cover most of the tropical oceans, and the prevailing cloud type is shallow cumulus. These small clouds are parameterized by climate models, and changes in their radiative effects strongly and directly contribute to the spread in estimates of climate sensitivity. This study investigates the structure and variability of these clouds in observations and climate models. The study builds upon recent detailed model evaluations using observations from the island of Barbados. Using a dynamical regimes framework, satellite and reanalysis products are used to compare the Barbados region and the broader tropics. It is shown that clouds in the Barbados region are similar to those across the trade wind regions, implying that observational findings from the Barbados Cloud Observatory are relevant to clouds across the tropics. The same methods are applied to climate models to evaluate the simulated clouds. The models generally capture the cloud radiative effect, but underestimate cloud cover and show an array of cloud vertical structures. Some models show strong biases in the environment of the Barbados region in summer, weakening the connection between the regional biases and those across the tropics. Even bearing that limitation in mind, it is shown that covariations of cloud and environmental properties in the models are inconsistent with observations. The models tend to misrepresent sensitivity to moisture variations and inversion characteristics. These model errors are likely connected to cloud feedback in climate projections, and highlight the importance of the representation of shallow cumulus convection.

9.
Acta amaz ; Acta amaz;37(1): 71-79, 2007. graf, tab
Article in Portuguese | LILACS | ID: lil-459253

ABSTRACT

Foram estudados os fenômenos meteorológicos que ocorrem na Amazônia Central (Manaus) utilizando-se um conjunto de imagens de satélites, com o objetivo de identificar as oscilações que mais contribuem para a variabilidade da cobertura de nuvens, e verificar se há modificações nestas oscilações em anos de El Niño e La Niña. O ciclo anual e o ciclo semi-anual são os principais responsáveis pela variabilidade da cobertura de nuvens altas na região. As oscilações interanuais associadas aos fenômenos El Niño/La Niña também contribuem fortemente para a variabilidade total da cobertura de nuvens altas. As oscilações intra-sazonais e interdiurnas apresentam uma variabilidade menor. Estendendo-se a análise para uma região compreendida de 1,5°S a 6°S e 68°W a 54°W, centrados em Manaus, observa-se que os períodos de 60, 45 e 30 dias possuem maior porcentagem de potência a leste de Manaus; o período de 20 dias possui maior porcentagem de potência no centro (próximo de Manaus); e os períodos de 8, 6 e 4 dias possuem maior porcentagem de potência a oeste de Manaus. As frentes frias que alcançam a janela de 10° de longitude e 2,5° de latitude centrada em Manaus, modulam de alguma forma a atividade convectiva na região de Manaus atuando como uma forçante das oscilações interdiurnas (47 por cento dos casos), das oscilações intra-sazonais, (15 por cento) e das oscilações de 55 a 65 dias (13 por cento). Convém ressaltar que não necessariamente as frentes frias causaram as oscilações. As frentes podem favorecer ou induzir a convecção no local.


The meteorological phenomena that occur in the Central Amazonia (Manaus) are studied from ISCCP-C1 Satellite- based data. The oscillations that contribute more significantly to the cloud cover variability and its relation to El Niño and La Niña events case identified. The annual and semi-annual oscillation times scales are the main responsible for the variability of the high cloud cover over Manaus. The inter-annual oscillations associated with El Niño and La Niña events also contribute significantly to the total variability of the high cloud cover, while intraseasonal and day-to-day oscillations show a reduced contribution. However, the intraseasonal and day-to-day oscillations are important since they do influence the predictability on short and medium range forecast. The studied region was extended to 21 sections, centered in Manaus. The 60, 45 and 30 day-oscillations exhibited a higher spectral power density percentage over eastern Manaus; the 20 day-oscillations, over the central Manaus; and the 8, 6 and 4 day-oscillations, over western Manaus. The cold fronts that reach central Amazonia modulate convective activity over Manaus region, acting as a forcing for day-to-day oscillations (47 percent of the cases), intraseasonal oscillations (15 percent), and 55 to 65 day- oscillations (13 percent). It is important to point out that the cold fronts did not necessarily establish the oscillations, but they may have favored or induced convection over Manaus region.


Subject(s)
Convection , Amazonian Ecosystem , Clouds
10.
Acta amaz. ; 37(1)2007.
Article in Portuguese | VETINDEX | ID: vti-450238

ABSTRACT

The meteorological phenomena that occur in the Central Amazonia (Manaus) are studied from ISCCP-C1 Satellite- based data. The oscillations that contribute more significantly to the cloud cover variability and its relation to El Niño and La Niña events case identified. The annual and semi-annual oscillation times scales are the main responsible for the variability of the high cloud cover over Manaus. The inter-annual oscillations associated with El Niño and La Niña events also contribute significantly to the total variability of the high cloud cover, while intraseasonal and day-to-day oscillations show a reduced contribution. However, the intraseasonal and day-to-day oscillations are important since they do influence the predictability on short and medium range forecast. The studied region was extended to 21 sections, centered in Manaus. The 60, 45 and 30 day-oscillations exhibited a higher spectral power density percentage over eastern Manaus; the 20 day-oscillations, over the central Manaus; and the 8, 6 and 4 day-oscillations, over western Manaus. The cold fronts that reach central Amazonia modulate convective activity over Manaus region, acting as a forcing for day-to-day oscillations (47% of the cases), intraseasonal oscillations (15%), and 55 to 65 day- oscillations (13%). It is important to point out that the cold fronts did not necessarily establish the oscillations, but they may have favored or induced convection over Manaus region.


Foram estudados os fenômenos meteorológicos que ocorrem na Amazônia Central (Manaus) utilizando-se um conjunto de imagens de satélites, com o objetivo de identificar as oscilações que mais contribuem para a variabilidade da cobertura de nuvens, e verificar se há modificações nestas oscilações em anos de El Niño e La Niña. O ciclo anual e o ciclo semi-anual são os principais responsáveis pela variabilidade da cobertura de nuvens altas na região. As oscilações interanuais associadas aos fenômenos El Niño/La Niña também contribuem fortemente para a variabilidade total da cobertura de nuvens altas. As oscilações intra-sazonais e interdiurnas apresentam uma variabilidade menor. Estendendo-se a análise para uma região compreendida de 1,5ºS a 6ºS e 68ºW a 54ºW, centrados em Manaus, observa-se que os períodos de 60, 45 e 30 dias possuem maior porcentagem de potência a leste de Manaus; o período de 20 dias possui maior porcentagem de potência no centro (próximo de Manaus); e os períodos de 8, 6 e 4 dias possuem maior porcentagem de potência a oeste de Manaus. As frentes frias que alcançam a janela de 10º de longitude e 2,5º de latitude centrada em Manaus, modulam de alguma forma a atividade convectiva na região de Manaus atuando como uma forçante das oscilações interdiurnas (47% dos casos), das oscilações intra-sazonais, (15%) e das oscilações de 55 a 65 dias (13%). Convém ressaltar que não necessariamente as frentes frias causaram as oscilações. As frentes podem favorecer ou induzir a convecção no local.

11.
Acta amaz. ; 35(2)2005.
Article in Portuguese | VETINDEX | ID: vti-450120

ABSTRACT

A review of results obtained within the Physical Climate component of LBA with respect to the interaction between the biosphere and cloud and rain formation in the Amazon Basin, in different seasons and different regions within the Basin is presented. The deforestation effect and the effect of biomass burning are discussed and the physical processes highlighted based on the data collected in several LBA intensive field campaigns. The complex interactions and the progress in the understanding their evolution based on the new datasets is presented.


Apresenta-se uma revisão dos resultados já obtidos no Projeto LBA, na componente de Física do Clima, referente ao efeito da interação entre a biosfera e a formação de nuvens e de chuva em diferentes estações do ano e regiões da Bacia Amazônica. O efeito do desmatamento e das queimadas na atmosfera é abordado assim como mecanismos atmosféricos que foram caracterizados a partir das diversas campanhas do projeto LBA. Uma visão da complexidade das interações e do progresso que tem sido feito com base nos dados colhidos é apresentada.

12.
Acta amaz. ; 35(2)2005.
Article in Portuguese | VETINDEX | ID: vti-450117

ABSTRACT

The understanding of the natural processes that regulate atmospheric composition in Amazonia is critical to the establishment of a sustainable development strategy in the region. The large emissions of trace gases and aerosols during the dry season, as a result of biomass burning, profoundly change the composition of the atmosphere in most of its area. The concentration of trace gases and aerosols increases by a factor of 2 to 8 over large areas, affecting the natural mechanisms of several key atmospheric processes in the region. Cloud formation mechanisms, for instance, are strongly affected when the concentration of cloud condensation nuclei (CCN) changes from 200-300 CCN/cc in the wet season to 5,000-10,000 CCN/cc in the dry season. The cloud droplet radius is reduced from values of 18 to 25 micrometers in the wet season to 5 to 10 micrometers in the dry season, suppressing cloud formation and the occurrence of precipitation under some conditions. Ozone is a key trace gas for changes in the forest health, with concentrations increasing from 12 parts per billion (ppb), at the wet season, to values as high as 100 ppb (in the dry season in areas strongly affected by biomass burning emissions). At this level, ozone could be damaging the vegetation in regions far from the emissions. The atmospheric radiation balance is also strongly affected, with a net loss of up to 70% of photosynthetic active radiation at the surface.


Entender os processos naturais que regulam a composição da atmosfera é crítico para que se possa desenvolver uma estratégia de desenvolvimento sustentável na região. As grandes emissões de gases e partículas durante a estação seca provenientes das queimadas alteram profundamente a composição da atmosfera amazônica na maior parte de sua área. As concentrações de partículas de aerossóis e gases traço aumentam por fatores de 2 a 8 em grandes áreas, afetando os mecanismos naturais de uma série de processos atmosféricos na região amazônica. Os mecanismos de formação de nuvens, por exemplo, são profundamente alterados quando a concentração de núcleos de condensação de nuvens (NCN) passa de 200 a 300 NCN/cm³ na estação chuvosa para 5.000-10.000 NCN/centímetro cúbico na estação seca. As gotas de nuvens sofrem uma redução de tamanho de 18 a 25 micrômetros para 5 a 10 micrômetros, diminuindo a eficiência do processo de precipitação e suprimindo a formação de nuvens. A concentração de ozônio, um gás importante para a saúde da floresta amazônica passa de cerca de 12 partes por bilhão em volume (ppb) (concentração típica ao meio do dia na estação chuvosa) para valores em regiões fortemente impactadas por queimadas de até 100 ppb, nível que pode ser fitotóxico para a vegetação. O balanço de radiação é fortemente afetado, com uma perda líquida de até 70% da radiação fotossinteticamente ativa na superfície.

13.
Semina ciênc. agrar ; 7(2): 54-59, 1986.
Article in Portuguese | LILACS-Express | VETINDEX | ID: biblio-1502044

ABSTRACT

Star counts of 3 southern dark clouds were performed using the techniques developed by Dickman (1976) in order to determine the visual extinction, AV, Using the ESO (B), SRC-J and ESO (R) plates, counts were made in the cloud and comparison fields, the latter being presumably free of obscurity. Various globules were identified in the clouds and parameters as dimension and visual extinction were estimated.


Neste trabalho, o método de contagem de estrelas desenvolvido por Dickman (1976) foi aplicado a 3 nuvens escuras do Hemisfério Celeste Sul, com o objetivo de determinar a sua extinção visual, A y As nuvens foram selecionadas a partir dos Atlas ESO (B), SRC-J e ESO (R) e as contagens feitas em 2 campos distintos: o campo da nuvem escura e o campo de comparação, livre de obscurecimento. A partir dos valores determinados de A y, vários glóbulos escuros foram reconhecidos e suai dimensões estimadas.

14.
Semina Ci. agr. ; 7(2): 54-59, 1986.
Article in Portuguese | VETINDEX | ID: vti-471163

ABSTRACT

Star counts of 3 southern dark clouds were performed using the techniques developed by Dickman (1976) in order to determine the visual extinction, AV, Using the ESO (B), SRC-J and ESO (R) plates, counts were made in the cloud and comparison fields, the latter being presumably free of obscurity. Various globules were identified in the clouds and parameters as dimension and visual extinction were estimated.  


Neste trabalho, o método de contagem de estrelas desenvolvido por Dickman (1976) foi aplicado a 3 nuvens escuras do Hemisfério Celeste Sul, com o objetivo de determinar a sua extinção visual, A y As nuvens foram selecionadas a partir dos Atlas ESO (B), SRC-J e ESO (R) e as contagens feitas em 2 campos distintos: o campo da nuvem escura e o campo de comparação, livre de obscurecimento. A partir dos valores determinados de A y, vários glóbulos escuros foram reconhecidos e suai dimensões estimadas.    

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