Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Dias, J." wg kryterium: Autor


Wyświetlanie 1-9 z 9
Tytuł:
Natural versus anthropic causes in variations of sand export from river basins: an example from the Guadiana River Mouth (Southwestern Iberia)
Autorzy:
Dias, J. M. A.
Gonzales, R.
Ferreira, Ó.
Powiązania:
https://bibliotekanauki.pl/articles/1187374.pdf
Data publikacji:
2004
Wydawca:
Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:
Guadiana River
sediment transport
estuarine sand bodies
floods
NAO
anthropic influence
Opis:
Flood events in many river basins with highly variable discharge values remove accumulated sediments from the riverbed and estuaries. These sediments are exported to the shelf and the adjacent coastlines. Data for rainfall and river discharge for the Guadiana River basin in southwestern Iberia show a strong link with North Atlantic Oscillation (NAO) index patterns. A negative NAO index usually results in more rainfall, and subsequent flooding in the river basin during winter months. During the second half of the 20th century, the flow regime of the Guadiana River and its tributaries have been increasingly constrained by the construction of dams. The consequences were a reduction of coarse-grained sediment export from the upper river basin to the estuary, and a reduction in the number and type of floods.
Źródło:
Polish Geological Institute Special Papers; 2004, 11; 95-102
1507-9791
Pojawia się w:
Polish Geological Institute Special Papers
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A comparison of algorithms for separation of synchronous subspaces
Autorzy:
Almeida, M.
Bioucas-Dias, J.
Vigário, R.
Oja, E.
Powiązania:
https://bibliotekanauki.pl/articles/201566.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
phase locking
synchrony
source separation
subspaces
Independent Component Analysis (ICA)
Independent Subspace Analysis (ISA)
magnetoencephalogram (MEG)
Opis:
Independent Subspace Analysis (ISA) consists in separating sets (subspaces) of dependent sources, with different sets being independent of each other. While a few algorithms have been proposed to solve this problem, they are all completely general in the sense that they do not make any assumptions on the intra-subspace dependency. In this paper, we address the ISA problem in the specific context of Separation of Synchronous Sources (SSS), i.e., we aim to solve the ISA problem when the intra-subspace dependency is known to be perfect phase synchrony between all sources in that subspace. We compare multiple algorithmic solutions for this problem, by analyzing their performance on an MEG-like dataset.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 3; 455-460
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Presenting a technique for registering images and range data using a topological representation of a path within an environment
Autorzy:
Ferreira, F.
Davim, L.
Rocha, R.
Dias, J.
Santos, V.
Powiązania:
https://bibliotekanauki.pl/articles/385035.pdf
Data publikacji:
2007
Wydawca:
Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
Tematy:
sensor feature integration
binary data
Bernoulli mixture model
dimensionality reduction
robot localisation
change detection
Opis:
This article presents a novel method to the utilize topological representation of a path, thatpath that is created from sequences of images from digital cameras and sensor data from range sensors. A topological representation of the environment is created by leading the robot around the environment during a familiarisation phaseLeading the robot around the environment during a familiarisation phase creates a topological representation of the environment. While moving down the same path, the robot is able to localise itself within the topological representation that is has been previously created. The principal contribution to the state of the art is that, by using a topological representation of the environment, individual 3D data sets acquired from a set of range sensors need not be registered in a single, [Global] Coordinate Reference System. Instead, 3D point clouds for small sections of the environment are indexed to a sequence of multi-sensor views, of images and range data. Such a registration procedure can be useful in the construction of 3D representations of large environments and in the detection of changes that might occur within these environments.
Źródło:
Journal of Automation Mobile Robotics and Intelligent Systems; 2007, 1, 3; 47-56
1897-8649
2080-2145
Pojawia się w:
Journal of Automation Mobile Robotics and Intelligent Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A smart and distributed measurement system to acquire and analyze mechanical motion parameters
Autorzy:
Pereira Dias, J. M.
Viegas, V.
Postolache, O.
Silva Girão, P.
Powiązania:
https://bibliotekanauki.pl/articles/221645.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
measurement system
kinematic variables measurements
accelerometers
error compensation
accuracy
Opis:
This paper presents a low-cost and smart measurement system to acquire and analyze mechanical motion parameters. The measurement system integrates several measuring nodes that include one or more triaxial accelerometers, a temperature sensor, a data acquisition unit and a wireless communication unit. Particular attention was dedicated to measurement system accuracy and compensation of measurement errors caused by power supply voltage variations, by temperature variations and by accelerometers’ misalignments. Mathematical relationships for error compensation were derived and software routines for measurement system configuration, data acquisition, data processing, and self-testing purposes were developed. The paper includes several simulation and experimental results obtained from an assembled prototype based on a crank-piston mechanism.
Źródło:
Metrology and Measurement Systems; 2013, 20, 3; 465-478
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Contact detection between convex superquadric surfaces
Detekcja kontaktu pomiędzy wypukłymi powierzchniami kwadratowymi
Autorzy:
Fontes Portal, R. J.
Pereira Dias, J. M.
Gonçalves de Sousa, L. A.
Powiązania:
https://bibliotekanauki.pl/articles/139474.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
detekcja kontaktu
kwadryki
powierzchnie superkwadratowe
optymalizacja
dynamika układów wieloczłonowych
contact detection
superquadrics
optimization
multibody dynamics
Opis:
This paper presents a methodology for contact detection between convex quadric surfaces using its implicit equations. With some small modifications in the equations, one can model superellipsoids, superhyperboloids of one or two sheets and supertoroids. This methodology is to be implemented on a multibody dynamics code, in order to simulate the interpenetration between mechanical systems, particularly, the simulation of collisions with motor vehicles and other road users, such as cars, motorcycles and pedestrians. The contact detection of two bodies is formulated as a convex nonlinear constrained optimization problem that is solved using two methods, an Interior Point method (IP) and a Sequential Quadratic Programming method (SQP), coded in MATLAB and FORTRAN environment, respectively. The objective function to be minimized is the distance between both surfaces. The design constraints are the implicit superquadrics surfaces equations and operations between its normal vectors and the distance itself. The contact points or the points that minimize the distance between the surfaces are the design variables. Computational efficiency can be improved by using Bounding Volumes in contact detection pre-steps. First one approximate the geometry using spheres, and then Oriented Bounding Boxes (OBB). Results show that the optimization technique suits for the accurate contact detection between objects modelled by implicit superquadric equations.
W artykule przedstawiono metodologię wykrywania kontaktu między wypukłymi powierzchniami typu kwadryki (superkwadratowymi) opisanymi równaniami uwikłanymi. Po niewielkich modyfikacjach równań, można modelować uogólnione elipsoidy, hiperboloidy jedno- lub dwupowłokowe oraz toroidy. Opisana metodologia ma być zaimplementowana w programie do symulacji układów wieloczłonowych i służyć do modelowania wzajemnej penetracji układów mechanicznych, w szczególności do symulacji kolizji pojazdów mechanicznych z innymi użytkownikami dróg, takimi jak samochody, motocykle i piesi. Zagadnienie detekcji kontaktu między dwoma ciałami jest formułowane jako wypukły, nieliniowy problem optymalizacyjny z ograniczeniami, który jest rozwiązywany przy użyciu dwu metod: metody punktu wewnętrznego (Interior Point, IP) oraz metody sekwencyjnego programowania kwadratowego (Sequential Quadratic Programming, SQP), dostępnych odpowiednio w środowiskach MATLAB i FORTRAN. Funkcja celu podlegająca minimalizacji jest odległością pomiędzy obiema powierzchniami. Ograniczeniami optymalizacji są uwikłane równania powierzchni drugiego stopnia oraz operacje pomiędzy ich wektorami do nich normalnymi i odległością. Zmiennymi decyzyjnymi są punkty kontaktu lub punkty wyznaczające minimalną odległość pomiędzy powierzchniami. Efektywność obliczeniową można poprawić stosując metodę objętości otaczających (Bounding Volumes) we wstępnych krokach detekcji kontaktu. Najpierw aproksymuje się geometrię ciał za pomocą kul, a następnie zorientowanych prostopadłościanów otaczających (Oriented Bounding Boxes, OBB). Wyniki pokazują, że taka technika optymalizacji zapewnia dokładną detekcję kontaktu pomiędzy obiektami modelowanymi przy użyciu uwikłanych równań powierzchni drugiego stopnia.
Źródło:
Archive of Mechanical Engineering; 2010, LVII, 2; 165-186
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using a segmented voltage sweep mode and a Gaussien curve fitting method to improve heavy metal measurement system performance
Autorzy:
Dias Pereira, J. M.
Postolache, O.
Silva Girao, P.
Powiązania:
https://bibliotekanauki.pl/articles/220629.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
heavy metals measurement
electrochemical analysis
voltammetry
auto-calibration and curve fitting
Opis:
This paper presents a voltammetric segmented voltage sweep mode that can be used to identify and measure heavy metals' concentrations. The proposed sweep mode covers a set of voltage ranges that are centered around the redox potentials of the metals that are under analysis. The heavy metal measurement system can take advantage of the historical database of measurements to identify the metals with higher concentrations in a given geographical area, and perform a segmented sweep around predefined voltage ranges or, alternatively, the system can perform a fast linear voltage sweep to identify the voltammetric current peaks and then perform a segmented voltage sweep around the set of voltages that are associated with the voltammetric current peaks. The paper also includes the presentation of two auto-calibration modes that can be used to improve system's reliability and proposes the usage of a Gaussian curve fitting of voltammetric data to identify heavy metals and to evaluate their concentrations. Several simulation and experimental results, that validate the theoretical expectations, are also presented in the paper.
Źródło:
Metrology and Measurement Systems; 2012, 19, 2; 381-394
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The role of kaolin and Bordeaux mixture in Vitis vinifera under water stress conditions: oxidative stress
Autorzy:
Dias, M.
Jesus, C.
Pinto, G.
Santos, C.
Goncalves, B.
Goncalves, D.
Malheiro, A.
Correia, C.
Moutinho-Pereira, J.
Powiązania:
https://bibliotekanauki.pl/articles/80420.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
conference
kaolin
Bordeaux mixture
Vitis vinifera
water stress
oxidative stress
grape-vine
plant stress
Źródło:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2013, 94, 2
0860-7796
Pojawia się w:
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mycoparasitic nature of Bionectria sp. strain 6.21
Autorzy:
Soares de Melo, I.
Montes Peral Valente, A.M.
Kavamura, V.N.
Dias Vilela, E.S.
Faull, J.L.
Powiązania:
https://bibliotekanauki.pl/articles/66229.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
In this study, a Bionectria sp. strain isolated from citrus rhizosphere was evaluated for its potential in inhibiting the growth of Rhizoctonia solani and Pythium aphanidermatum. It was demonstrated that Bionectria sp. 6.21 inhibited the growth of P. aphanidermatum and R. solani. In dual cultures, however, the antagonist only parasitised R. solani. Regarding the assay involving P. aphanidermatum, a lack of mycoparasitic ability was demonstrated. Crude extract of Bionectria completely inhibited the mycelial growth of both fungi. It appears that the main mechanism involved in the antagonism of Pythium by Bionectria is through antibiotic production. The antagonistic fungus released extracellular secondary metabolites. The metabolites were found to be inhibitory to both plant pathogenic fungi. From the crude extract, eleven fractions were obtained and tested for their antifungal properties. Two of them showed very strong activity against P. aphanidermatum. The obtained results indicated that this biocontrol agent has both antibiotic and mycoparasitic properties. On the other hand, evidence obtained from Scanning Electron Microscopy (SEM) suggests the involvement of an enzymatic process, with enzymatic digestion playing a major role in the parasitism of Bionectria sp. 6.21. In conclusion, these results provide evidence that mainly due to mycoparasitism, this strain has the potential to become a good candidate for biological control.
Źródło:
Journal of Plant Protection Research; 2014, 54, 4
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Railway industry roadmap in the state of Santa Catarina, Brazil
Roadmap para a indústria ferroviário do estado de Santa Catarina, Brasil
Autorzy:
Dias, A.
Da Silva, J. C.
Kagueiama, H. H.
Haddad, C. R.
Uriona, M. M.
Lezana, Á. G. R.
Juliatto, D. L.
Powiązania:
https://bibliotekanauki.pl/articles/374823.pdf
Data publikacji:
2015
Wydawca:
Politechnika Śląska. Wydawnictwo Politechniki Śląskiej
Tematy:
technology
roadmapping
rail industry
technologia
mapa drogowa
przemysł kolejowy
branża kolejowa
Opis:
This article aims to identify the main requirements to strengthen the railroad industry in Santa Catarina by using technology roadmapping. The railway industry is composed of carriers, manufacturers, suppliers, operators, logistics, services and education. The survey aimed to provide guidelines for the Federation of the State of Santa Catarina Industry (FIESC) to develop its strategic plan for the next eight years. Based on the survey, the roadmap defined vision, mission, a list of key concepts, drivers and actions for the Federation to support the railway industry development, since this industrial sector is still economically unrepresented when compared to other sectors in Santa Catarina. The survey also pointed out there is a strong expansion program of the railway freight and railway transport for people in Brazil, both in government and private sectors.
Este artigo objetiva identificar os principais requisitos para fortalecer a indústria ferroviária em Santa Catarina (SC), por meio da aplicação do processo de technology roadmapping. A indústria ferroviária é composta por transportadores, fabricantes, fornecedores, operadores de logística, serviços e educação. A pesquisa objetivou fornecer orientações para a Federação das Indústrias de Santa Catarina (FIESC) com a finalidade de desenvolver um plano estratégico para os próximos oito anos. Baseando-se na pesquisa, definiram-se a visão, missão e uma lista de conceitos chaves, drivers e ações para que a FIESC apoiasse o desenvolvimento da indústria ferroviária, uma vez que esta é economicamente pouco representativa em comparação com outras indústrias no estado de SC. A pesquisa apontou que há forte expansão do transporte de cargas e pessoas no Brasil, tanto nos setores governamentais quanto nos setores privados.
Źródło:
Transport Problems; 2015, T. 10, z. spec.; 29-36
1896-0596
2300-861X
Pojawia się w:
Transport Problems
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-9 z 9

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies