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[pt] DESENVOLVIMENTO DE PLATAFORMA PARA TESTES E SIMULAÇÃO DE SISTEMAS MULTICÓPTEROS / [en] DEVELOPMENT OF A PLATFORM FOR TESTS AND SIMULATION OF MULTICOPTER SYSTEMSRENAN DE LIMA SIMOES MONDEGO VILELA 25 February 2021 (has links)
[pt] O crescente uso de veículos aéreos não tripulados (VANTs) em diversos setores
da sociedade é fruto de avanços da tecnologia. Por sua vez, a ampliação de
aplicações de VANTs traz consigo a necessidade de aumento de robustez destes
sistemas, especialmente em ambientes compartilhados com o ser humano. A
presente dissertação aborda o desenvolvimento de uma plataforma para testes
de veículos multicópteros, com o objetivo de contribuir para o processo de desenvolvimento
e implementação de drones, permitindo sua movimentação em
torno dos seus graus de liberdade de rotação e realizando medições de atitude
e força geradas pelo sistema, sem colocar o veículo ou seu operador em
risco. Todos os dados adquiridos pela plataforma são transmitidos para um
computador, onde foi desenvolvida uma interface virtual para sua visualização
em tempo real, além de permitir armazenamento para pós-processamento
e análises futuras. Também apresenta-se e discute-se o desenvolvimento do
simulador de trajetórias proposto, que mostra o deslocamento do veículo em
função da sequência de comandos fornecida, com base nos dados adquiridos
pela plataforma. No intuito de se propiciar um melhor entendimento do funcionamento
do sistema aqui desenvolvido, é apresentado um estudo detalhado
dos subsistemas que compõem um multicóptero, bem como do processo de
modelagem dinâmica de um veículo quadricóptero, por meio da técnica de
grafos de ligação. A modelagem do veículo é complementada com a identificação
de parâmetros fundamentais para a implementação do modelo, sendo
discutidos métodos para identificação de parâmetros inerciais do veículo e
parâmetros dinâmicos do sistema motopropulsor. / [en] The growing use of unmanned aerial vehicles (UAVs) in various sectors
of society is a result of advances in technology. In turn, the expansion of
UAV applications brings with it the need to increase the robustness of these
systems, especially in environments shared with humans. and comes together
with the need for increased robustness due to its use in shared environments
with humans. This dissertation approaches the development of a platform
for testing multicopter vehicles aiming at assisting the process of developing
and implementing drones, allowing movements around their rotational degrees
of freedom and making measurements of attitude and forces generated by
the system, without putting the vehicle or its operator at risk. All data
acquired by the platform is transmitted to a computer, where a virtual
interface was developed to provide real time visualization, in addition to
allowing data storage for post-processing and future analysis. The development
of the proposed trajectory simulator is also presented and discussed, that
shows the displacement of the vehicle as a function of the sequence of
commands provided, based on the acquired data. Aiming at allowing a better
understanding of the functioning of the developed system, a detailed study
of the subsystems that compose a multicopter is presented, as well as the
process of dynamic modeling of a quadcopter vehicle, by using bond graph
technique. The modeling of the vehicle is complemented with the identification
of fundamental parameters for the model implementation, such as methods for
the identification of inertial parameters of the vehicle and dynamics of the
powertrain system.
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Parameter Identification Methodology for Thermal Modeling of Li-ion BatteriesKhanna, Yatin 06 September 2022 (has links)
No description available.
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Advanced State Estimation For Electric Vehicle BatteriesRahimifard, Sara Sadat January 2022 (has links)
Lithium-ion (Li-ion) batteries are amongst the most commonly used types in Electric (EVs) and Hybrid Electric (HEVs) Vehicles due to their high energy and power densities, as well as long lifetime. A battery is one of the most important components of an EV and hence it needs to be monitored and controlled accurately. The safety, and reliability of battery packs must then, be ensured by accurate management, control, and monitoring functions by using a Battery Management System (BMS).
A BMS is also responsible for accurate real-time estimation of the State of Charge (SoC), State of Health (SoH) and State of Power (SoP) of the battery. The battery SoC provides information on the amount of energy left in the battery. The SoH determines the remaining capacity and health of a pack, and the SoP represents the maximum available power. These critical battery states cannot be directly measured. Therefore, they have to be inferred from measurable parameters such as the current delivered by the battery as well as its terminal voltage. Consequently, in order to offer
accurate monitoring of SoC, SoH and SoP, advanced numerical estimation methods need to be deployed.
In the estimation process, the states and parameters of a system are extracted from measurements. The objective is to reduce the estimation errors in the presence of uncertainties and noise under different operating conditions. This thesis uses and provides different enhancements to a robust estimation strategy referred to as the Smooth Variable Structure Filter (SVSF) for condition monitoring of batteries. The SVSF is a predictor-corrector method based on sliding mode control that enhances the robustness in the presence of noise and uncertainties. The methods are proposed to
provide accurate estimates of the battery states of operation and can be implemented in real-time in BMS.
To improve the performance of battery condition monitoring, a measurement-based SoC estimation method called coulomb counting is paired with model-based state estimation strategy. Important considerations in parameter and state estimation are model formulation and observability. In this research, a new model formulation that treats coulomb counting as an added measurement is proposed. It is shown that this formulation enhanced information extraction, leading to a more accurate state estimation, as well as an increase in the number of parameters and variables that
can be estimated while maintaining observability. This model formulation is used for characterizing the battery in a range of operating conditions. In turn, the models are integral to a proposed adaptive filter that is a combination of the Interacting Multiple Model (IMM) concept and the SVSF. It is shown that this combined strategy is an efficient estimation approach that can effectively deal with battery aging. The proposed method provides accurate estimation for various SoH of a battery.
Further to battery aging adaptation, measurement errors such as sensor noise, drift, and bias that affect estimation performance, are considered. To improve the accuracy of battery state estimation, a noise covariance adaptation scheme is developed for the SVSF method. This strategy further improves the robustness of the SVSF in the presence of unknown physical disturbances, noise, and initial conditions. The proposed estimation strategies are also considered for their implementation on battery packs. An important consideration in pack level battery management is
cell-to-cell variations that impact battery safety. This study considers online battery parametrization to update the pack’s model over time and to detect cell-to-cell variability in parallel-connected battery cells configurations. Experimental data are used to validate and test the efficacy of the proposed methods in this thesis. / Thesis / Doctor of Philosophy (PhD) / To address the critical issue of climate change, it is necessary to replace fossil-fuel vehicles with battery-powered electric vehicles. Despite the benefits of electric vehicles, their popularity is still limited by the range anxiety and the cost determined by the battery pack. The range of an electric vehicle is determined by the amount of charge in its battery pack. This is comparable to the amount of gasoline in a gasoline vehicle’s tank. In consideration of the need for methods to address range anxiety, it is necessary to develop advanced algorithms for continuous monitoring and control of a battery pack to maximize its performance. However, the amount of charge and health of a battery pack cannot be measured directly and must be inferred from measurable variables including current, voltage and temperature. This research presents several algorithms for detecting the range and health of a battery pack under a variety of operating conditions. With a more accurate algorithm, a battery pack can be monitored closely, resulting in lower long-term costs. Adaptive methods for determining a battery’s state of charge and health in uncertain and noisy conditions have been developed to provide an accurate measure of available charge and capacity. Methods are then extended to improve the determination of state of charge and health for a battery module.
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A crank angle resolved CIDI engine combustion model with arbitrary fuel injection for control purposeKim, Chung-Gong 18 June 2004 (has links)
No description available.
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Développement d'une stratégie d'identification des paramètres par recalage de modèle éléments finis à partir de mesures par corrélation d'images : vers l'application à un modèle d'endommagement non local / Development of a parameter identification strategy using Finite Element Model Updating on Digital Image Correlation measurements : towards the application to a non-local modelBettonte, Francesco 13 November 2017 (has links)
Cette thèse a pour objectif le développement d'une stratégie d'identification des paramètres de plasticité et d'endommagement jusqu'à amorçage, pour des métaux ductiles.Un formalisme logarithmique est utilisé pour simuler les grandes déformations subies par les éprouvettes et une formulation non-locale multi-champ permet de simuler l'adoucissement indépendamment du maillage utilisé et d'éviter le verrouillage volumique.La Corrélation d'Images Digitales est utilisée pour obtenir des mesures hétérogènes plein champ à partir d'éprouvettes entaillées.La stratégie proposée s'appuie sur des observations microscopiques et sur une approche d'identification par recalage de modèle éléments finis (FEMU), visant à minimiser l'écart entre une mesure et son pendant simulé. L'écart est exprimé en termes de force et déplacement grâce à une normalisation appropriée. L'application de la FEMU est guidée par des analyses de sensibilité.La robustesse de la comparaison essai-calcul est assurée par l'application de conditions au bord mesurées. L'effet négatif de l’incertitude de mesure est mis en évidence et une solution de filtrage innovante est proposée.La stratégie est appliquée pour l'identification des paramètres de l'alliage Inconel625. Elle permet de reproduire l'amorçage pour des éprouvettes planes, en termes de réponse macroscopique et de localisation des sites d'amorçage. / This thesis proposes an identification strategy for plastic behaviour and damage up to the onset of fracture, for an application to ductile metals.A logarithmic finite strain formulation is used to simulate the large deformations undergone by the specimens, while a locking-free non-local formulation allows a mesh independent simulation of the softening behaviour.Digital Image Correlation is used to obtain heterogeneous full-field measurements from tensile tests on notched specimens.The identification strategy is based both on microscopic observations and on a Finite Element Model Updating (FEMU) technique, according to which the parameters are identified by minimizing the discrepancy between experiment and simulation. The discrepancy is quantified both in terms of displacement and force thanks to an appropriate normalization. The application of FEMU is guided using sensitivity analysis.The robustness of the comparison between simulation and measurement is ensured by prescribing measured displacements as boundary conditions for the simulation. The negative effect of the measurement uncertainty is underlined, and an innovative filtering approach is proposed.The proposed strategy is used to identify the materials' parameters of alloy Inconel625. It allows to reproduce the onset of fracture for flat specimens, both in terms of macroscopic response and crack initiation location.
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Projeto e análise de controladores não lineares aplicados a um sistema de levitação eletromagnética. / Project and analysis of nonlinear controllers applied to a magnetic levitation system.Carneiro, Breno Garcia 21 September 2016 (has links)
Sistemas de levitação eletromagnética são de interesse quando se necessita de tecnologia envolvendo redução de atrito, atuação sem contato físico, máquinas rotativas e trens de alta velocidade. Devido à presença de não linearidades em sua dinâmica, pesquisadores têm dado atenção ao desenvolvimento de controladores mais sofisticados, com o objetivo de melhorar o desempenho desses sistemas. Controladores lineares apresentam limitações na faixa de operação da variável controlada e, geralmente apresentam baixa robustez quando aplicados em sistemas não lineares. O objetivo deste trabalho é desenvolver controladores não lineares com diferentes estruturas e analisá-los quando aplicados em um protótipo do sistema físico. Inicialmente, o sistema é modelado matematicamente através da abordagem fenomenológica. Em seguida, os parâmetros do modelo são identificados através de dados obtidos experimentalmente. Conhecendo bem a dinâmica do sistema através do modelo, são projetados três controladores de diferentes estruturas utilizando simulações computacionais. O primeiro é o PID clássico, controle linear amplamente utilizado em processos industriais. O segundo controlador é um PID com topologia não linear, denominado NPID. Este visa reduzir as limitações encontradas no PID linear, através de funções não lineares em seus termos. O último e mais complexo se trata do controle por modos deslizantes (SMC). Também com estrutura não linear, o SMC possui como característica intrínseca a robustez a variações da planta. Ao final, são realizadas simulações e os controladores avaliados são implementados de maneira digital em um hardware de controle e aplicados em uma planta piloto de levitação eletromagnética. Os resultados de desempenho obtidos permitem avaliar qual topologia de controlador melhor se enquadra diante dessa aplicação. / Electromagnetic levitation systems are of interest when it is necessary the use of technology involving reduction of friction, acting without physical contact, rotating machinery and high speed trains. Due to the nonlinear dynamics, researchers have paid attention to the development of more sophisticated controllers, in order to improve the performance of these systems. Linear controllers have limitations in the operating range of the controlled variable and generally have low robustness when applied to linear systems. The objective of this work is to develop nonlinear controllers with different structures and analyze them, when applied to a prototype of the physical system. Initially the system is modeled mathematically through the phenomenological approach. Then the model parameters are identified by experimentally obtained data. Knowing the dynamic of the system through the model, three different controllers are designed using computer simulations. The first is the classic PID, a linear control widely used in industrial processes. The second controller is a PID with nonlinear topology, called NPID. This controller is intended to reduce the limitations found in the linear PID through non linear functions on its terms. The last and most complex is the sliding mode control (SMC). Also a nonlinear structure, the SMC has the intrinsic characteristic of robustness to variations of the plant. In the end, the simulations are performed and the evaluated controllers are implemented in digital form in a hardware control and applied in a pilot plant of an electromagnetic levitation system. With the performance results it is possible to verify which controller topology best fits this application.
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Identification et commande des robots manipulateurs à bas prix / Identification and control of low-cost robot manipulatorsShao, Zilong 24 March 2016 (has links)
Contrairement aux robots manipulateurs industriels qui sont de taille énorme et de prix élevé, beaucoup de robots manipulateurs à bas prix sont déjà entrés dans le marché, avec une petite taille, un poids léger, ce type de robots est plus accessible pour les particuliers. Cependant, limité par le coût de revient, des accessoires (matériaux, actuateurs, contrôleurs, etc) adoptés sont aussi limités, cela conduit souvent à la performance moins robuste au niveau de contrôle. Cette thèses se concentre sur la conception de contrôleur pour améliorer la performance des robots manipulateurs à bas prix. D'abord, pour des robots manipulateurs rigides, la modélisation dynamique en lien avec le système d'actualisation est établie, qui forme une équation différentielle avec paramètres constants et perturbation. Une méthode d'identification des paramètres en utilisant des observateurs et une commande adaptative sont proposées, et des résultats de simulation et d'expérimentation sont donnés. Ensuite, pour le cas d'articulation flexibles, pour simplifier, le modèle 1DOF est pris en compte. Premièrement, avec la mesure de la vitesse de lien, une méthode d'identification et une loi deux-étages adaptative sont proposées à condition que la position statique de lien puisse également être mesurée, des résultats de simulation sont donnés. Deuxièmement, en utilisant des mesures d'accélération de lien, une méthode d'identification et la même loi deux-étages adaptative sont proposées, cette idée est généralisée à l'identification et au contrôle de systèmes linéaires avec mesures de dérivées d'ordre élevé, des résultat de simulation sont présentés. Pour la mise en œuvre, des capteurs inertiels (gyroscopes et accéléromètres) sont utilisés et des résultats expérimentaux sont présentés. / Unlike industrial robot manipulators which are huge in size and of high price, many low-cost robot manipulators have already entered the market, with small size and light weight, this type of robots are more accessible to the public. However, limited by the cost, the components adopted (materials, actuators, controllers, etc.) are also limited, this often leads to less robust control performance. This thesis focuses on the controller design to improve the performance for such kind low-cost robot manipulators. To start with, for rigid case, dynamic modeling considering the actuator system is established, which forms a differential equation with constant parameters and disturbance, a method to identify the model parameters using observers and then an adaptive controller are proposed, simulation and experimental results are given. Then, in case of flexible joints, for simplicity, a single-link case model is considered. Firstly, link velocity measurement is assumed to provide link information, and an identification method and a two-stage adaptive control low are proposed provided that the static link position can also be measured, simulation result is given. Secondly, by using link acceleration measurement, an identification method and the same two-stage adaptive control low areproposed, this idea is generalized to identification and control of linear system using high-order derivative measurements, simulation result is presented. For implementation, inertial sensors (gyro and accelerometer) are used and experimental result is presented.
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Prolifération des cellules T dans des conditions lymphopéniques : modélisation, estimation des paramètres et analyse mathématique / T cell proliferation in lymphopenia conditions : modeling, parameters estimation and mathematical analysisAyoub, Houssein 04 July 2014 (has links)
Les lymphocytes T sont une composante essentielle du système immunitaire de l'organisme. Ils peuvent reconnaître et répondre à un antigène étranger en vertu de leur récepteur d'antigène. En effet, les cellules T qui n'ont pas encore rencontrées des antigènes, sont appelées "naïves". Lors d'un premier contact antigénique, l'expansion clonale des lymphocytes T spécifiques a un antigène augmente fortement leur fréquence, et déséquilibre transitoirement de façon plus ou moins intense le compartiment lymphocytaire T périphérique. Cet équilibre doit être rétabli pour ne pas menacer à terme le bon fonctionnement du système immunitaire. Outre le risque de réponse explosive lors d'une réexposition à l'antigène, l'accumulation de clones T de taille disproportionnée gênerait considérablement le recrutement de lymphocytes T spécifiques de nouveaux antigènes. Ainsi, après élimination de l'antigène ou son confinement dans l'organisme, différents mécanismes interviennent. Il faut en effet d'une part assurer le maintien d'un compartiment de cellules T naïves de taille suffisante pour faire face à de nouvelles stimulations antigéniques. D'autre part, la constitution d'un panel de cellules T mémoires est nécessaire pour permettre une réponse immunitaire plus rapide et plus efficace lors de réexpositions antigéniques. Donc les mécanismes d'homéostasie des cellules T sont essentielles pour maintenir le nombre de cellules T à un niveau à peu près constant en contrôlant la division cellulaire et la mortalité des cellules. [...] / T lymphocytes are a fundamental component of the immune system that can recognise and respond to foreign antigens by virtue of their clonally expressed T cell antigen receptor (TCR). T cells that have yet to encounter the antigen they recognise are termed 'naive' as they have not been activated to respond. Homeostatic mechanisms maintain the number of T cells at an approximately constant level by controling cell division and death. In normal replete hosts, cell turnover within the naive compartment is very low and naive cells are maintained in a resting state.However, disruption of the homeostatic balance can arise from a wide variety of causes (viral infection (e.g. HIV), or drugs used in peritransplant induction therapy or cancer chemotherapy) and can result in T cell deciency or T lymphopenia. Under conditions of T lymphopenia, naive T cells undergo cell division with a subtle change in the cell surface phenotype (CD44 expression), termed homeostatic proliferation or lymphopenia induced proliferation (LIP). In this thesis, our purpose is to understand the process of T cell homeostatic through mathematical approach. At first, we build a new model that describes the proliferation of T cells in vitro under lymphopenic conditions. Our nonlinear model is composed of ordinary differential equations and partial differential equations structured by age (maturity of cell) and CD44 expression. To better understand the homeostasis of T cells, we identify the parameters that define T cell division by using experimental data. Next, we consider an age-structured model system describing the T cell homeostatic in vivo, and we investigate its asymptotic behaviour. Finally, an optimal strategy is applied in the in vivo model to rebuild immunity under conditions of T lympopenia.
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Identification inverse de paramètres biomécaniques en hyperélasticité anisotrope / Inverse identification of biological parameters in anisotropic hyperelasticityHarb, Nizar 20 June 2013 (has links)
Les travaux de cette thèse s'inscrivent dans le cadre du développement de méthodes d'identification inverse de paramètres matériau. On porte un intérêt particulier à la biomécanique des tissus souples renforcés par des fibres de collagène (artère, disque intervertébral, peau, tendon, ligament, etc.), dans le cadre de leurs réponses viscoélastiques et en grandes déformations et en grands déplacements (hyperélasticité). Fortement non-linéaires et anisotropes, les lois constitutives en biomécanique contiennent un nombre important de paramètres matériau. Le problème inverse qui permet de les identifier est de grande dimension et fortement non linéaire. En raison de difficultés numériques liées à sa résolution avec des méthodes à base de gradient, nous avons développé deux nouvelles méthodes d’identification inverse de paramètres nommées GAO (Genetic algorithms & Analytical Optimization) et MMIM (Maximum-Minimum Identification Method).La méthode GAO combine de manière avantageuse les méthodes déterministes de type gradient avec les algorithmes génétiques. Son originalité consiste à introduire des calculs analytiques pour la partie déterministe, ce qui permet d’accélérer et d’améliorer la convergence des algorithmes génétiques. Cette stratégie est appliquée dans le cadre de l’hyperélasticité anisotrope.En ce qui concerne la méthode MMIM, elle opère selon un critère d’identification basé sur la norme infinie et elle utilise les algorithmes génétiques. Elle permet d’identifier les paramètres de lois viscoélastiques quasi-linéaires. Elle garantit une réponse visqueuse constante qui est caractéristique des tissus souples qui sont insensibles à la vitesse de chargement.Les méthodes GAO et MMIM ont identifié avec succès des paramètres de tissus artériels et de tissus du disque intervertébral. Les propriétés de ces tissus sont décrits par ailleurs dans le mémoire dans un contexte plus général où on expose l'anatomie, l'histologie et le mécanisme de déformation aux différents niveaux hiérarchiques (nano-échelle à milli-échelle) d’un tissu souple renforcé par des fibres de collagène. Ceci permet de comprendre le rôle des efforts dans la relation liant la structure à la fonction en biologie. / This thesis focuses on research and development of inverse identification methods of material parameters. A particular attention is attributed to the viscoelastic response of collagen-reinforced soft tissues (artery, intervertebral disc, skin, tendon, ligament, etc) submitted to large displacements and large deformations (hyperelasticity). Highly non-linear and anisotropic, biomechanical constitutive laws account for a large number of material parameters. The inverse problem that allows their identification is of high non-linearity and of large dimension. By reason of numerical difficulties related to its resolution with gradient-based methods, we developed two new identification methods labelled GAO (Genetic algorithms & Analytical Optimization) and MMIM (Maximum-Minimum Identification Method).GAO advantageously combines deterministic methods of gradient type with genetic algorithms. Its originality consists in introducing analytical computations for the deterministic part leading to a gain in the speed up and in the convergence of genetic algorithms. This strategy is used in the context of anisotropic hyperelasticity.Regarding MMIM method, it operates according to an identification criterion that is expressed with the infinite norm and uses genetic algorithms. MMIM method identifies parameters of quasi-linear viscoelastic laws. It guarantees a constant viscous response that characterises the insensitivity of soft tissues to strain rate. GAO and MMIM methods successfully identified parameters of arterial wall and intervertebral disc tissues. The properties of these tissues are described in a more general context that exhibits the anatomy, histology and deformation mechanism at different hierarchical levels (nano-scale to milli-scale) of collagen-reinforced soft tissues. This gives understanding of the role of forces in relating structure to function in biology.
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Interval Based Parameter Identification for System Biology / Intervallbaserad parameteridentifiering för systembiologiAlami, Mohsen January 2012 (has links)
This master thesis studies the problem of parameter identification for system biology. Two methods have been studied. The method of interval analysis uses subpaving as a class of objects to manipulate and store inner and outer approximations of compact sets. This method works well with the model given as a system of differential equations, but has its limitations, since the analytical expression for the solution to the ODE is not always obtainable, which is needed for constructing the inclusion function. The other method, studied, is SDP-relaxation of a nonlinear and non-convex feasibility problem. This method, implemented in the toolbox bio.SDP, works with system of difference equations, obtained using the Euler discretization method. The discretization method is not exact, raising the need of bounding this discretization error. Several methods for bounding this error has been studied. The method of ∞-norm optimization, also called worst-case-∞-norm is applied on the one-step error estimation method. The methods have been illustrated solving two system biological problems and the resulting SCP have been compared. / Det här examensarbetet studerar problemet med parameteridentifiering för systembiologi. Två metoder har studerats. Metoden med intervallanalys använder union av intervallvektorer som klass av objekt för att manipulera och bilda inre och yttre approximationer av kompakta mängder. Denna metod fungerar väl för modeller givna som ett system av differentialekvationer, men har sina begränsningar, eftersom det analytiska uttrycket för lösningen till differentialekvationen som är nödvändigt att känna till för att kunna formulera inkluderande funktioner, inte alltid är tillgängliga. Den andra studerade metoden, använder SDP-relaxering, som ett sätt att komma runt problemet med olinjäritet och icke-konvexitet i systemet. Denna metod, implementerad i toolboxen bio.SDP, utgår från system av differensekvationer, framtagna via Eulers diskretiserings metod. Diskretiseringsmetoden innehåller fel och osäkerhet, vilket gör det nödvändigt att estimera en gräns för felets storlek. Några felestimeringsmetoder har studerats. Metoden med ∞-norm optimering, också kallat worst-case-∞-norm är tillämpat på ett-stegs felestimerings metoder. Metoderna har illustrerats genom att lösa två system biologiska problem och de accepterade parametermängderna, benämnt SCP, har jämförts och diskuterats.
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