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- Universidade Federal do Rio Grande do Sul
- Editora da Universidade Estadual de Maringá (EDUEM)
- Sociedade Brasileira de Física
- Editora da Universidade Estadual de Maringá - EDUEM
- Oxford University Press
- JAIDS Journal of Acquired Immune Deficiency Syndromes
- Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL
- Trans Tech Publications
- Universidade Cornell
- Institute of Electrical and Electronics Engineers (IEEE)
- Latin American applied research
- Mais Publicadores...

## Métodos para diagnóstico e integração de sistemas de gestão; Management system diagnostic and integration methods

Fonte: Universidade Federal do Rio Grande do Sul
Publicador: Universidade Federal do Rio Grande do Sul

Tipo: Dissertação
Formato: application/pdf

POR

Relevância na Pesquisa

45.99%

#Sistema integrado de gestão#Integrated management system#ISO#Indústria metal-mecânica#OHSAS#Integration#Diagnostic

A crescente implementação de sistemas de gestão da qualidade, saúde, segurança e meio ambiente tem despertado nas organizações o interesse pela integração destes sistemas. A necessidade de se definir quais requisitos normativos são comuns a todos os sistemas implementados e quais devem ser integrados, além da identificação da situação atual da empresa em relação ao atendimento e integração destes requisitos, abre cada vez mais espaço para elaboração de métodos organizados para planejamento, execução e controle desta integração. Um dos objetivos deste trabalho foi inicialmente elaborar um método para diagnóstico do nível de integração de sistemas de gestão baseados nas normas ISO9001, ISO14001 e OHSAS18001 e a avaliação deste método através da aplicação prática em uma empresa do ramo metal-mecânico. Baseado no estudo de caso mencionado, foi possível identificar o nível de integração da organização em relação a 19 requisitos normativos comuns às 3 normas e após foram sugeridas melhorias para os sistemas da empresa. Com os resultados do diagnóstico e a análise de um caso de insucesso da integração de sistemas de gestão em uma empresa do ramo metal-mecânico, a dissertação apresenta como objetivo principal um método de integração de sistemas de gestão baseados nas normas ISO9001...

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## Comparison of methodologies for degree-day estimation using numerical methods

Fonte: Editora da Universidade Estadual de Maringá (EDUEM)
Publicador: Editora da Universidade Estadual de Maringá (EDUEM)

Tipo: Artigo de Revista Científica
Formato: 391-400

ENG

Relevância na Pesquisa

55.96%

#desenvolvimento vegetativo#unidades térmicas#métodos de integração numérica#cana-de-açúcar#vegetative development#heat units#numerical integration methods#sugar cane

O desenvolvimento de projetos relacionados ao desempenho de diversas culturas tem recebido aperfeiçoamento cada vez maior, incorporado a modelos matemáticos sendo indispensável à utilização de equações cada vez mais consistentes que possibilitem previsão e maior aproximação do comportamento real, diminuindo o erro na obtenção das estimativas. Entre as operações unitárias que demandam maior estudo estão aquelas relacionadas com o crescimento da cultura, caracterizadas pela temperatura ideal para o acréscimo de matéria seca. Pelo amplo uso dos métodos matemáticos na representação, análise e obtenção de estimativas de graus-dia, juntamente com a grande importância que a cultura da cana-de-açúcar tem para a economia brasileira, foi realizada uma avaliação dos modelos matemáticos comumente usados e dos métodos numéricos de integração na estimativa da disponibilidade de graus-dia para essa cultura, na região de Botucatu, Estado de São Paulo. Os modelos de integração, com discretização de 6 em 6 h, apresentaram resultados satisfatórios na estimativa de graus-dia. As metodologias tradicionais apresentaram desempenhos satisfatórios quanto à estimativa de grausdia com base na curva de temperatura horária para cada dia e para os agrupamentos de três...

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## Symplectic integration methods in molecular and spin dynamics simulations

Fonte: Sociedade Brasileira de Física
Publicador: Sociedade Brasileira de Física

Tipo: Artigo de Revista Científica
Formato: text/html

Publicado em 01/06/2004
EN

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We review recently developed decomposition algorithms for molecular dynamics and spin dynamics simulations of many-body systems. These methods are time reversible, symplectic, and the error in the total energy thus generated is bounded. In general, these techniques are accurate for much larger time steps than more standard integration methods. Illustrations of decomposition algorithms performance are shown for spin dynamics simulations of a Heisenberg ferromagnet.

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## Comparison of methodologies for degree-day estimation using numerical methods

Fonte: Editora da Universidade Estadual de Maringá - EDUEM
Publicador: Editora da Universidade Estadual de Maringá - EDUEM

Tipo: Artigo de Revista Científica
Formato: text/html

Publicado em 01/09/2011
EN

Relevância na Pesquisa

55.96%

The development of projects related to the yield of various crops has been greatly enhanced with the incorporation of mathematical models as well as essential and more consistent equations which enable a prediction and greater approximation to their actual behavior, thus reducing error in estimate. Among the operations requiring further investigation are those related to crop growth, characterized by the ideal temperature for addition of dry matter. Due to the wide use of mathematical methods for representing, analyzing and attaining degree-day estimation as well as the great importance of sugarcane in the Brazilian economy, we carried out an evaluation of the mathematical models and numerical integration methods commonly used for estimating the availability of degrees-day for this crop in the region of Botucatu, in São Paulo State, Brazil. Integration models with discretization every 6 hours have shown satisfactory results in degree-day estimation. Conventional methodologies have shown satisfactory results when the estimation of degrees-day was based on the time-temperature curve for each day and for groups of 3, 7, 15 and 30 days. Through numerical integration method, the region of Botucatu showed a annual thermal availability average from 1...

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## Integration of DNA into bacterial chromosomes from plasmids without a counter-selection marker

Fonte: Oxford University Press
Publicador: Oxford University Press

Tipo: Artigo de Revista Científica

EN

Relevância na Pesquisa

45.92%

Most bacteria can only be transformed with circular plasmids, so robust DNA integration methods for these rely upon selection of single-crossover clones followed by counter-selection of double-crossover clones. To overcome the limited availability of heterologous counter-selection markers, here we explore novel DNA integration strategies that do not employ them, and instead exploit (i) activation or inactivation of genes leading to a selectable phenotype, and (ii) asymmetrical regions of homology to control the order of recombination events. We focus here on the industrial biofuel-producing bacterium Clostridium acetobutylicum, which previously lacked robust integration tools, but the approach we have developed is broadly applicable. Large sequences can be delivered in a series of steps, as we demonstrate by inserting the chromosome of phage lambda (minus a region apparently unstable in Escherichia coli in our cloning context) into the chromosome of C. acetobutylicum in three steps. This work should open the way to reliable integration of DNA including large synthetic constructs in diverse microorganisms.

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## Health Systems Integration of Sexual and Reproductive Health and HIV Services in Sub-Saharan Africa: A Scoping Study

Fonte: JAIDS Journal of Acquired Immune Deficiency Syndromes
Publicador: JAIDS Journal of Acquired Immune Deficiency Syndromes

Tipo: Artigo de Revista Científica

EN_US

Relevância na Pesquisa

45.91%

#reproductive health services#HIV#health systems research#maternal health services#integration#linkage

Objective: Both sexual and reproductive health (SRH) services and HIV programs in sub-Saharan Africa are typically delivered vertically, operating parallel to national health systems. The objective of this study was to map the evidence on national and international strategies for integration of SRH and HIV services in sub-Saharan Africa and to develop a research agenda for future health systems integration. Methods: We examined the literature on national and international strategies to integrate SRH and HIV services using a scoping study methodology. Current policy frameworks, national HIV strategies and research, and gray literature on integration were mapped. Five countries in sub-Saharan Africa with experience of integrating SRH and HIV services were purposively sampled for detailed thematic analysis, according to the health systems functions of governance, policy and planning, financing, health workforce organization, service organization, and monitoring and evaluation. Results: The major international health policies and donor guidance now support integration. Most integration research has focused on linkages of SRH and HIV front-line services. Yet, the common problems with implementation are related to delayed or incomplete integration of higher level health systems functions: lack of coordinated leadership and unified national integration policies; separate financing streams for SRH and HIV services and inadequate health worker training...

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## Uma estratégia de adaptação no tempo baseada na curvatura do histórico de deslocamentos; A time adaptive strategy based on displacement history curvature

Fonte: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL
Publicador: Universidade Federal de Alagoas; BR; Estruturas; Programa de Pós-Graduação em Engenharia Civil; UFAL

Tipo: Dissertação
Formato: application/pdf

POR

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45.99%

#Adaptação no tempo#Métodos de integração direta#Estimadores de refinamento#Curvatura#Time adaptive integration#Direct integration methods#Refinement estimators#Curvature#CNPQ::ENGENHARIAS::ENGENHARIA CIVIL

This work introduces a time adaptive strategy that uses a refinement estimator based on the geometric indicator of curvature. The developed methodology is suitable for problems of numerical time integration present, for example, in the study of bodies subjected to dynamical loads. The refinement estimator demands low computational resources, being easily applied to several direct integration methods. Trying to interact these methods, an object oriented library that uses the developed scheme of adaptation is built. The main idea of this tool is to incorporate this scheme, in an easy way, in existing computational codes that employ direct integration methods. Examples of dynamic solid bodies are presented, ilustrating the technique and library usage in existing applications.; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior; Este trabalho introduz uma estratégia de adaptação no tempo que utiliza um estimador de refinamento baseado no indicador geométrico curvatura. A metodologia desenvolvida é aplicada ao problema de integração numérica temporal, presente, por exemplo, no estudo do comportamento de corpos submetidos a cargas dinâmicas. O estimador de refinamento formulado demanda pouco esforço computacional, sendo facilmente aplicado aos diversos métodos de integração direta existentes. Visando a interação com esses métodos...

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## Characterization of virtual nano-structures through the use of Monte Carlo integration

Fonte: Trans Tech Publications
Publicador: Trans Tech Publications

Tipo: Artigo de Revista Científica

Publicado em //2008
EN

Relevância na Pesquisa

45.85%

#Accessible Volume#Monte Carlo Integration#Pore Size Distribution#Solid Characterisation#Surface Area

The determination of the properties of porous solids remains an integral element to the understanding of adsorption, transport and reaction processes in new and novel materials. The advent of molecular simulation has led to an improved understanding and prediction of adsorption processes using molecular models. These molecular models have removed the constraints of traditional adsorption theories, which require rigid assumptions about the structure of a material. However, even if we possess a full molecular model of a solid, it is still desirable to define the properties of this solid in a standard manner with quantities such as the accessible volume, surface area and pore size distribution. This talk will present Monte Carlo integration methods for calculating these quantities in a physically meaningful and unambiguous way. The proposed methods for calculating the surface area and pore size distribution were tested on an array of idealised solid configurations including cylindrical and cubic pores. The method presented is adequate for all configurations tested giving confidence to its applicability to disordered solids. The method is further tested by using several different noble gas probe molecules. Finally, the results of this technique are compared against those obtained by applying the BET equation for a range of novel materials.; Luis F. Herrera...

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## Functional determinants by contour integration methods

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 05/05/2003

Relevância na Pesquisa

45.78%

We present a simple and accessible method which uses contour integration
methods to derive formulae for functional determinants. To make the
presentation as clear as possible, the general idea is first illustrated on the
simplest case: a second order differential operator with Dirichlet boundary
conditions. The method is applicable to more general situations, and we discuss
the way in which the formalism has to be developed to cover these cases. In
particular, we also show that simple and elegant formulae exist for the
physically important case of determinants where zero modes exist, but have been
excluded.; Comment: 29 pages

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## On the impact of explicit or semi-implicit integration methods over the stability of real-time numerical simulations

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 20/11/2013

Relevância na Pesquisa

45.96%

Physics-based animation of soft or rigid bodies for real-time applications
often suffers from numerical instabilities. We analyse one of the most common
sources of unwanted behaviour: the numerical integration strategy. To assess
the impact of popular integration methods, we consider a scenario where soft
and hard constraints are added to a custom designed deformable linear object.
Since the goal for this class of simulation methods is to attain interactive
frame-rates, we present the drawbacks of using explicit integration methods
over inherently stable, implicit integrators. To help numerical solver
designers better understand the impact of an integrator on a certain simulated
world, we have conceived a method of benchmarking the efficiency of an
integrator with respect to its speed, stability and symplecticity.; Comment: Submitted to the ROMAI Journal of Applied Mathematics. Presented at
the CAIM 2013 Conference on Applied and Industrial Mathematics

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## Hamiltonian integration methods for Vlasov-Maxwell equations

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 22/05/2015

Relevância na Pesquisa

45.89%

Hamiltonian integration methods for the Vlasov-Maxwell equations are
developed by a Hamiltonian splitting technique. The Hamiltonian functional is
split into five parts, i.e., the electrical energy, the magnetic energy, and
the kinetic energy in three Cartesian components. Each of the subsystems is a
Hamiltonian system with respect to the Morrison-Marsden-Weinstein Poisson
bracket and can be solved exactly. Compositions of the exact solutions yield
Poisson structure preserving, or Hamiltonian, integration methods for the
Vlasov-Maxwell equations, which have superior long-term fidelity and accuracy.

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## Elementary Integration Methods for Velocity Excitations in Displacement Digital Waveguides

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 19/07/2004

Relevância na Pesquisa

45.94%

Elementary integration methods for waveguides are compared. One using
non-local loading rules based on Heaviside step functions, one using input side
integration and one using integration of the output of traveling velocity
waves. We show that most approaches can be made consistent with the wave
equation in principle, under proper circumstances. Of all methods studied the
Heaviside method is the only method shown to not suffer from undesirable
numerical difficulties and amendable to standard waveguide loop filtering
practices, yet it gives incorrect results for Neumann boundary conditions. We
also discuss localized velocity excitations, time-limited input-side
excitations and the relation of loop filters to wave variable type.; Comment: 8 pages, no figures (yet), draft, comments are very welcome

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## The Adams-Bashforth-Moulton Integration Methods Generalized to an Adaptive Grid

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 15/04/2011

Relevância na Pesquisa

45.92%

We present a generalization of the Adams-Bashforth-Moulton
predictor-corrector numerical integration methods to an adaptive grid. The step
size may be chosen dynamically in order to maintain a desired relative
magnitude of error in each step. We demonstrate that the methods remain
convergent to the expected degree, and apply various methods to the famous
problem of determining the maximum possible mass of a neutron star supported by
pure fermionic exclusion pressure. We reproduce the Tolman-Oppenheimer-Volkoff
result of 0.71 solar masses using only 23 integration steps, and reproducing
both mass and radius within 1% requires 27. We also present various
optimizations and features of our implementation.; Comment: 8 figures, one table included as png image or eps file

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## Energy conservation and dissipation properties of time-integration methods for the nonsmooth elastodynamics with contact

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 09/10/2014

Relevância na Pesquisa

45.85%

This research report is devoted to the study of the conservation and the
dissipation properties of the mechanical energy of several time--integration
methods dedicated to the elasto--dynamics with unilateral contact. Given that
the direct application of the standard schemes as the Newmark schemes or the
generalized--$\alpha$ schemes leads to energy blow-up, we study two schemes
dedicated to the time--integration of nonsmooth systems with contact: the
Moreau--Jean scheme and the nonsmooth generalized--$\alpha$ scheme. The energy
conservation and dissipation properties of the Moreau--Jean is firstly shown.
In a second step, the nonsmooth generalized--$\alpha$ scheme is studied by
adapting the previous works of Krenk and H{\o}gsberg in the context of
unilateral contact. Finally, the known properties of the Newmark and the
Hilber--Hughes--Taylor (HHT) scheme in the unconstrained case are extended
without any further assumptions to the case with contact.; Comment: 29 pages

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## Numerical integration methods for large-scale biophysical simulations

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 29/03/2009

Relevância na Pesquisa

45.78%

Simulations of biophysical systems inevitably include steps that correspond
to time integrations of ordinary differential equations. These equations are
often related to enzyme action in the synthesis and destruction of molecular
species, and in the regulation of transport of molecules into and out of the
cell or cellular compartments. Enzyme action is almost invariably modeled with
the quasi-steady-state Michaelis-Menten formula or its close relative, the Hill
formula: this description leads to systems of equations that may be stiff and
hard to integrate, and poses unusual computational challenges in simulations
where a smooth evolution is interrupted by the discrete events that mark the
cells' lives. This is the case of a numerical model (Virtual Biophysics Lab -
VBL) that we are developing to simulate the growth of three-dimensional tumor
cell aggregates (spheroids). The program must be robust and stable, and must be
able to accept frequent changes in the underlying theoretical model: here we
study the applicability of known integration methods to this unusual context
and we describe the results of numerical tests in situations similar to those
found in actual simulations.; Comment: 11 figures, submitted to Computer Physics Communications

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## An introduction to particle integration methods: with applications to risk and insurance

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Relevância na Pesquisa

45.92%

#Quantitative Finance - Computational Finance#Mathematics - Statistics Theory#Quantitative Finance - Risk Management

Interacting particle methods are increasingly used to sample from complex and
high-dimensional distributions. These stochastic particle integration
techniques can be interpreted as an universal acceptance-rejection sequential
particle sampler equipped with adaptive and interacting recycling mechanisms.
Practically, the particles evolve randomly around the space independently and
to each particle is associated a positive potential function. Periodically,
particles with high potentials duplicate at the expense of low potential
particle which die. This natural genetic type selection scheme appears in
numerous applications in applied probability, physics, Bayesian statistics,
signal processing, biology, and information engineering. It is the intention of
this paper to introduce them to risk modeling. From a purely mathematical point
of view, these stochastic samplers can be interpreted as Feynman-Kac particle
integration methods. These functional models are natural mathematical
extensions of the traditional change of probability measures, commonly used to
design an importance sampling strategy. In this article, we provide a brief
introduction to the stochastic modeling and the theoretical analysis of these
particle algorithms. Then we conclude with an illustration of a subset of such
methods to resolve important risk measure and capital estimation in risk and
insurance modelling.

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## On the minimal accuracy required for simulating self-gravitating systems by means of direct N-body methods

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 26/02/2014

Relevância na Pesquisa

45.89%

#Astrophysics - Instrumentation and Methods for Astrophysics#Computer Science - Computational Complexity

The conservation of energy, linear momentum and angular momentum are
important drivers for our physical understanding of the evolution of the
Universe. These quantities are also conserved in Newton's laws of motion under
gravity \citep{Newton:1687}. Numerical integration of the associated equations
of motion is extremely challenging, in particular due to the steady growth of
numerical errors (by round-off and discrete time-stepping,
\cite{1981PAZh....7..752B,1993ApJ...415..715G,1993ApJ...402L..85H,1994LNP...430..131M})
and the exponential divergence \citep{1964ApJ...140..250M,2009MNRAS.392.1051U}
between two nearby solution. As a result, numerical solutions to the general
N-body problem are intrinsically questionable
\citep{2003gmbp.book.....H,1994JAM....61..226L}. Using brute force integrations
to arbitrary numerical precision we demonstrate empirically that ensembles of
different realizations of resonant 3-body interactions produce statistically
indistinguishable results. Although individual solutions using common
integration methods are notoriously unreliable, we conjecture that an ensemble
of approximate 3-body solutions accurately represents an ensemble of true
solutions, so long as the energy during integration is conserved to better than
1/10. We therefore provide an independent confirmation that previous work on
self-gravitating systems can actually be trusted...

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## Efficient time integration methods based on operator splitting and application to the Westervelt equation

Fonte: Universidade Cornell
Publicador: Universidade Cornell

Tipo: Artigo de Revista Científica

Publicado em 05/11/2013

Relevância na Pesquisa

45.78%

Efficient time integration methods based on operator splitting are introduced
for the Westervelt equation, a nonlinear damped wave equation that arises in
nonlinear acoustics as mathematical model for the propagation of sound waves in
high intensity ultrasound applications. For the first-order Lie-Trotter
splitting method a global error estimate is deduced, confirming that the
splitting method remains stable and that the nonstiff convergence order is
retained in situations where the problem data are sufficiently regular.
Fundamental ingredients in the stability and error analysis are regularity
results for the Westervelt equation and related linear evolution equations of
hyperbolic and parabolic type. Numerical examples illustrate and complement the
theoretical investigations.

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## Representation of transmission lines: comparison of models and parameters distributed discrete parameters

Fonte: Institute of Electrical and Electronics Engineers (IEEE)
Publicador: Institute of Electrical and Electronics Engineers (IEEE)

Tipo: Artigo de Revista Científica
Formato: 1047-1052

ENG

Relevância na Pesquisa

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#Cascade circuits#Distributed parameters#Electromagnetic transients#Lumped#Numerical integration methods#Transmission lines#Cascade circuit#Distributed parameter#Electro-magnetic transient#Numerical integration methods#Differential equations

A transmission line is characterized by the fact that its parameters are distributed along its length. This fact makes the voltages and currents along the line to behave like waves and these are described by differential equations. In general, the differential equations mentioned are difficult to solve in the time domain, due to the convolution integral, but in the frequency domain these equations become simpler and their solutions are known. The transmission line can be represented by a cascade of π circuits. This model has the advantage of being developed directly in the time domain, but there is a need to apply numerical integration methods. In this work a comparison of the model that considers the fact that the parameters are distributed (Universal Line Model) and the fact that the parameters considered concentrated along the line (π circuit model) using the trapezoidal integration method, and Simpson's rule Runge-Kutta in a single-phase transmission line length of 100 km subjected to an operation power. © 2003-2012 IEEE.

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## Linearly implicit discrete event methods for stiff ODE's.

Fonte: Latin American applied research
Publicador: Latin American applied research

Tipo: Artigo de Revista Científica
Formato: text/html

Publicado em 01/07/2009
EN

Relevância na Pesquisa

45.99%

This paper introduces two new numerical methods for integration of stiff ordinary differential equations. Following the idea of quantization based integration, i.e., replacing the time discretization by state quantization, the new methods perform first and second order backward approximations allowing to simulate stiff systems. It is shown that the new algorithms satisfy the same theoretical properties of previous quantization-based integration methods. The translation of the new algorithms into a discrete event (DEVS) specification and its implementation in a DEVS simulation tool is discussed. The efficience of the methods is illustrated comparing the simulation of two examples with the classic methods implemented by Matlab/Simulink.

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