Bibliografie tematiche / Algorithme de flots

Letteratura scientifica selezionata sul tema "Algorithme de flots"

Autore: Grafiati

Pubblicato: 1 giugno 2024

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Articoli di riviste sul tema "Algorithme de flots":

Parker, Michael J., Mark A. Lovich, Amy C. Tsao, Abraham E. Wei, Matthew G. Wakim, Mikhail Y. Maslov, Hisashi Tsukada e Robert A. Peterfreund. "Computer Control of Drug Delivery by Continuous Intravenous Infusion". Anesthesiology 122, n. 3 (1 marzo 2015): 647–58. http://dx.doi.org/10.1097/aln.0000000000000519.

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Abstract Background: Intravenous drug infusion driven by syringe pumps may lead to substantial temporal lags in achieving steady-state delivery at target levels when using very low flow rates (“microinfusion”). This study evaluated computer algorithms for reducing temporal lags via coordinated control of drug and carrier flows. Methods: Novel computer control algorithms were developed based on mathematical models of fluid flow. Algorithm 1 controlled initiation of drug infusion and algorithm 2 controlled changes to ongoing steady-state infusions. These algorithms were tested in vitro and in vivo using typical high and low dead volume infusion system architectures. One syringe pump infused a carrier fluid and a second infused drug. Drug and carrier flowed together via a manifold through standard central venous catheters. Samples were collected in vitro for quantitative delivery analysis. Parameters including left ventricular max dP/dt were recorded in vivo. Results: Regulation by algorithm 1 reduced delivery delay in vitro during infusion initiation by 69% (low dead volume) and 78% (high dead volume). Algorithmic control in vivo measuring % change in max dP/dt showed similar results (55% for low dead volume and 64% for high dead volume). Algorithm 2 yielded greater precision in matching the magnitude and timing of intended changes in vivo and in vitro. Conclusions: Compared with conventional methods, algorithm-based computer control of carrier and drug flows can improve drug delivery by pump-driven intravenous infusion to better match intent. For norepinephrine infusions, the amount of drug reaching the bloodstream per time appears to be a dominant factor in the hemodynamic response to infusion.

Ekanayake, E. M. U. S. B., W. B. Daundasekara e S. P. C. Perera. "New Approach to Obtain the Maximum Flow in a Network and Optimal Solution for the Transportation Problems". Modern Applied Science 16, n. 1 (21 gennaio 2022): 30. http://dx.doi.org/10.5539/mas.v16n1p30.

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The maximum flow problem is also one of the highly regarded problems in the field of optimization theory in which the objective is to find a feasible flow through a flow network that obtains the maximum possible flow rate from source to sink. The literature demonstrates that different techniques have been developed in the past to handle the maximum amount of flow that the network can handle. The Ford-Fulkerson algorithm and Dinic's Algorithm are the two major algorithms for solving these types of problems. Also, the Max-Flow Min-Cut Theorem, the Scaling Algorithm, and the Push–relabel maximum flow algorithm are the most acceptable methods for finding the maximum flows in a flow network. In this novel approach, the paper develops an alternative method of finding the maximum flow between the source and target nodes of a network based on the "max-flow." Also, a new algorithmic approach to solving the transportation problem (minimizing the transportation cost) is based upon the new maximum flow algorithm. It is also to be noticed that this method requires a minimum number of iterations to achieve optimality. This study's algorithmic approach is less complicated than the well-known meta-heuristic algorithms in the literature. 

Wang, Yipu. "Max Flows in Planar Graphs with Vertex Capacities". ACM Transactions on Algorithms 18, n. 1 (31 gennaio 2022): 1–27. http://dx.doi.org/10.1145/3504032.

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We consider the maximum flow problem in directed planar graphs with capacities on both vertices and arcs and with multiple sources and sinks. We present three algorithms when the capacities are integers. The first algorithm runs in O ( min { k 2 n , n log 3 n + kn }) time when all capacities are bounded by a constant, where n is the number of vertices in the graph, and k is the number of terminals. This algorithm is the first to solve the vertex-disjoint paths problem in linear time when k is fixed but larger than 2. The second algorithm runs in O ( k 5 Δ n polylog ( nU )) time, where each arc capacity and finite vertex capacity is bounded by U , and Δ is the maximum degree of the graph. Finally, when k = 3, we present an algorithm that runs in O ( n log n ) time; this algorithm works even when the capacities are arbitrary reals. Our algorithms improve on the fastest previously known algorithms when k and Δ are fixed and U is bounded by a polynomial in n . Prior to this result, the fastest algorithms ran in O ( n 4/3+ o (1) ) time for unit capacities; in the smallest of O ( n 3/2 log n log U ), Õ( n 10/7 U 1/7 ), O ( n 11/8+o(1) U 1/4 ), and O ( n 4/3 + o(1) U 1/3 ) time for integer capacities; and in O ( n 2 /log n ) time for real capacities, even when k = 3.

Chen, Li, Rasmus Kyng, Yang P. Liu, Richard Peng, Maximilian Probst Gutenberg e Sushant Sachdeva. "Almost-Linear-Time Algorithms for Maximum Flow and Minimum-Cost Flow". Communications of the ACM 66, n. 12 (17 novembre 2023): 85–92. http://dx.doi.org/10.1145/3610940.

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We present an algorithm that computes exact maximum flows and minimum-cost flows on directed graphs with m edges and polynomially bounded integral demands, costs, and capacities in m 1+ o (1) time. Our algorithm builds the flow through a sequence of m 1+ o (1) approximate undirected minimum-ratio cycles, each of which is computed and processed in amortized m o (1) time using a new dynamic graph data structure. Our framework extends to algorithms running in m 1+ o (1) time for computing flows that minimize general edge-separable convex functions to high accuracy. This gives almost-linear time algorithms for several problems including entropy-regularized optimal transport, matrix scaling, p -norm flows, and p -norm isotonic regression on arbitrary directed acyclic graphs.

Ali, Gohar, Fernando Moreira, Omar Alfandi, Babar Shah e Mohammed Ilyas. "A New Intra-Cluster Scheduling Scheme for Real-Time Flows in Wireless Sensor Networks". Electronics 9, n. 4 (23 aprile 2020): 683. http://dx.doi.org/10.3390/electronics9040683.

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Real-time flows using time division multiple access (TDMA) scheduling in cluster-based wireless sensor networks try to schedule more flows per time frame to minimize the schedule length to meet the deadline. The problem with the previously used cluster-based scheduling algorithm is that intra-cluster scheduling does not consider that the clusters may have internal or outgoing flows. Thus, intra-cluster scheduling algorithms do not utilize their empty time-slots and thus increase schedule length. In this paper, we propose a new intra-cluster scheduling algorithm by considering that clusters may have having internal or outgoing flows. Thus, intra-cluster scheduling algorithms do not differentiate the intra-cluster time slots and utilize their empty time slots. The objective is to schedule more flows per time frame, to reduce schedule length and improve the acceptance rate of flows. Simulation results show that the acceptance rate of the proposed scheme has a higher performance than the previous scheme.

Bt Ismail, Shafinaz, Darmawaty Bt Mohd Ali e Norsuzila Ya’acob. "Performance Analysis of Uplink Scheduling Algorithms in LTE Networks". Indonesian Journal of Electrical Engineering and Computer Science 9, n. 2 (1 febbraio 2018): 373. http://dx.doi.org/10.11591/ijeecs.v9.i2.pp373-379.

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Scheduling is referring to the process of allocating resources to User Equipment based on scheduling algorithms that is located at the LTE base station. Various algorithms have been proposed as the execution of scheduling algorithm, which represents an open issue in Long Term Evolution (LTE) standard. This paper makes an attempt to study and compare the performance of three well-known uplink schedulers namely, Maximum Throughput (MT), First Maximum Expansion (FME), and Round Robin (RR). The evaluation is considered for a single cell with interference for three flows such as Best effort, Video and VoIP in a pedestrian environment using the LTE-SIM network simulator. The performance evaluation is conducted in terms of system throughput, fairness index, delay and packet loss ratio (PLR). The simulations results show that RR algorithm always reaches the lowest PLR, delivering highest throughput for video and VoIP flows among all those strategies. Thus, RR is the most suitable scheduling algorithm for VoIP and video flows while MT and FME is appropriate for BE flows in LTE networks.

Joung, Jinoo, Yunki Choi e Sunghoon Son. "An improved algorithm for Detection of Elephant Flows". Journal of Korea Information and Communications Society 37B, n. 9 (30 settembre 2012): 849–58. http://dx.doi.org/10.7840/kics.2012.37b.9.849.

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Begouen Demeaux, Charlotte, e Emmanuel Boss. "Validation of Remote-Sensing Algorithms for Diffuse Attenuation of Downward Irradiance Using BGC-Argo Floats". Remote Sensing 14, n. 18 (9 settembre 2022): 4500. http://dx.doi.org/10.3390/rs14184500.

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Estimates of the diffuse attenuation coefficient (Kd) at two different wavelengths and band-integrated (PAR) were obtained using different published algorithms developed for open ocean waters spanning in type from explicit-empirical, semi-analytical and implicit-empirical and applied to data from spectral radiometers on board six different satellites (MODIS-Aqua, MODIS-Terra, VIIRS–SNPP, VIIRS-JPSS, OLCI-Sentinel 3A and OLCI-Sentinel 3B). The resultant Kds were compared to those inferred from measurements of radiometry from sensors on board autonomous profiling floats (BGC-Argo). Advantages of BGC-Argo measurements compared to ship-based ones include: 1. uniform sampling in time throughout the year, 2. large spatial coverage, and 3. lack of shading by platform. Over 5000 quality-controlled matchups between Kds derived from float and from satellite sensors were found with values ranging from 0.01 to 0.67 m−1. Our results show that although all three algorithm types provided similarly ranging values of Kd to those of the floats, for most sensors, a given algorithm produced statistically different Kd distributions from the two others. Algorithm results diverged the most for low Kd (clearest waters). Algorithm biases were traced to the limitations of the datasets the algorithms were developed and trained with, as well as the neglect of sun angle in some algorithms. This study highlights: 1. the importance of using comprehensive field-based datasets (such as BGC-Argo) for algorithm development, 2. the limitation of using radiative-transfer model simulations only for algorithm development, and 3. the potential for improvement if sun angle is taken into account explicitly to improve empirical Kd algorithms. Recent augmentation of profiling floats with hyper-spectral radiometers should be encouraged as they will provide additional constraints to develop algorithms for upcoming missions such as NASA’s PACE and SBG and ESA’s CHIME, all of which will include a hyper-spectral radiometer.

Wu, Tian-Yu, Jianfei Zhang, Yanjun Dai, Tao-Feng Cao, Kong Ling e Wen-Quan Tao. "Implementation of IDEAL algorithm based on Delaunay triangular mesh for 2D-compressible flows". Engineering Computations 41, n. 3 (7 maggio 2024): 630–54. http://dx.doi.org/10.1108/ec-02-2023-0071.

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PurposeTo present the detailed implementation processes of the IDEAL algorithm for two-dimensional compressible flows based on Delaunay triangular mesh, and compare the performance of the SIMPLE and IDEAL algorithms for solving compressible problems. What’s more, the implementation processes of Delaunay mesh generation and derivation of the pressure correction equation are also introduced.Design/methodology/approachProgramming completely in C++.FindingsFive compressible examples are used to test the SIMPLE and IDEAL algorithms, and the comparison with measurement data shows good agreement. The IDEAL algorithm has much better performance in both convergence rate and stability over the SIMPLE algorithm.Originality/valueThe detail solution procedure of implementing the IDEAL algorithm for compressible flows based on Delaunay triangular mesh is presented in this work, seemingly first in the literature.

Tsekeris, Theodore, e Antony Stathopoulos. "Real-Time Dynamic Origin-Destination Matrix Adjustment with Simulated and Actual Link Flows in Urban Networks". Transportation Research Record: Journal of the Transportation Research Board 1857, n. 1 (gennaio 2003): 117–27. http://dx.doi.org/10.3141/1857-14.

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The efficiency and robustness of different real-time dynamic origin–destination (O-D) matrix adjustment algorithms were investigated when implemented in large-scale transportation networks. The proposed algorithms produce time-dependent O-D trip matrices based on the maximum-entropy trip departure times with simulated and actual observed link flows. Implementation of the algorithms, which are coupled with a quasi-dynamic traffic assignment model, indicated their convergent behavior and their potential for handling realistic urban-scale network problems in terms of both accuracy and computational time. The main factors influencing the numerical performance of each algorithm were identified and analyzed. Their relative efficiency was found to be particularly dependent on the level at which the assigned flows approximate the observed link flows. These results may provide insights into the suitability of each algorithm for diverse application domains, including freeways, small networks, and large-scale urban networks, where a different quality of O-D information is usually available.

Più fonti

Tesi sul tema "Algorithme de flots":

Gueth, Frederic. "Observations interférométriques des flots moléculaires L1157 et HH211". Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10202.

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La formation des etoiles s'accompagne de puissants phenomenes d'ejection de matiere, qui se traduisent par la presence de flots moleculaires bipolaires autour de la plupart des protoetoiles. Cette these etudie la structure interne des flots moleculaires, a l'aide d'observations interferometriques millimetriques realisees a l'interferometre du plateau de bure de l'iram. Les cartes presentees figurent parmi les toutes premieres images de flots moleculaires realisees avec une resolution angulaire aussi elevee (de l'ordre de la seconde d'arc). Deux flots extremement jeunes (environ 10000 ans) et leurs protoetoiles excitatrices sont etudies, a travers l'emission de co et sio. Le flot moleculaire de l 1157 revele deux cavites distinctes, dont les distributions de brillance et les proprietes cinematiques peuvent etre reproduite par un modele de precession. Une forte interaction prend place entre le flot et l'enveloppe entourant la protoetoile. Cette derniere montre de plus une signature d'effondrement gravitationnel. Le flot de hh 211 presente quant a lui une structure remarquable dans laquelle un jet moleculaire rapide emerge de la source centrale et est entoure d'une cavite detectee a plus faible vitesse. La forme de cette derniere correspond parfaitement aux predictions de modeles simples de propagation d'un choc en arc. Plusieurs aspects des observations de l 1157 et hh 211 sont egalement discutes, parmis lesquels les mecanismes de formation des flots moleculaires (la propagation de larges chocs en arc semble etre l'hypothese la plus pertinente) et les processus de formation de la molecule sio dans les flots. Finalement, la deuxieme partie de cette these presente les algorithmes de reconstruction et de deconvolution, adaptes au cas des observations interferometriques de mosaiques, qui ont ete developpes pour permettre les observations decrites precedemment.

Vernet, Mathilde. "Modèles et algorithmes pour les graphes dynamiques". Thesis, Normandie, 2020. http://www.theses.fr/2020NORMLH12.

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Les problèmes de graphes ont été largement étudiés dans le cas des graphes statiques. Cependant, ces graphes ne permettent pas de prendre en compte la dimension temporelle, qui est souvent une donnée importante pour les situations à modéliser. Les graphes dynamiques viennent combler ces lacunes en permettant de modéliser des évolutions dans le temps. On peut alors s'interroger sur ces mêmes problèmes de graphes dans un contexte dynamique. Cela passe d'abord par la définition du modèle de graphes dynamiques le plus approprié et la modélisation précise du problème sur ces graphes. Lorsque le problème ne peut pas être résolu efficacement en appliquant directement des méthodes connues sur les graphes statiques, il faut alors concevoir un algorithme de résolution spécifique aux graphes dynamiques et l'analyser théoriquement et expérimentalement.En suivant cette démarche, l'objectif de cette thèse est de s'interroger sur l'extension aux graphes dynamiques des problèmes bien connus sur les graphes statiques. Ce travail s'intéresse à plusieurs problèmes de graphes en contexte dynamique en se focalisant sur les aspects algorithmiques et en s'abstrayant des domaines d'applications
Graph problems have been widely studied in the case of static graphs. However, these graphs do not allow a time dimension to be considered, even though time is an important variable for the situations to model. Dynamic graphs make it possible to model evolution over time. This is a reason to wonder about graph problems in a dynamic context. First, it is necessary to define the most appropriate dynamic graphs model and the precise problem on those graphs. When the problem cannot be efficiently solved directly using known static graph methods, an algorithm specific to dynamic graphs must be designed and analyzed theoretically and practically.With that approach, this thesis' objective is to study graph problems' extensions to dynamic graphs. This works deals with several graph problems in a dynamic context by focusing on algorithmic aspects and without considering application domains

Bouchakour, Mustapha. "Composition de graphes et le polytope des absorbantsUn algorithme de coupes pour le problème du flots a coûts fixes". Rennes 1, 1996. http://www.theses.fr/1996REN10196.

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Cette these est composee de deux parties: la premiere partie porte sur le probleme des absorbants de poids minimum. Nous nous interessons au polytope des solutions de ce probleme. Dans un premier temps, nous decrivons certaines facettes de base et nous discutons de certaines proprietes structurales de ce polytope. Par la suite, nous considerons ce polytope dans les graphes decomposables par des sommets d'articulation. Si g est un graphe qui se decompose en deux graphes g#1 et g#2, alors on montre que le polytope des absorbants dans g peut etre decrit a partir de deux systemes lineaires lies a g#1 et g#2. Ceci donne lieu a une technique permettant de caracteriser le polytope des absorbants dans les classes de graphes qui sont recursivement decomposables. Nous obtenons egalement une procedure de composition de facettes dans ce type de graphes. Nous montrons que le probleme de l'absorbant peut etre aussi decompose. Des applications de cette technique sont discutees pour la classe des cactus. Nous etudions aussi des procedures generales de construction de facettes. Dans la deuxieme partie, nous etudions le probleme du flot quand les couts fixes et des couts variables sont associes aux arcs du graphe. Nous developpons une approche polyedrale pour ce probleme. Nous introduisons des nouvelles contraintes valides pour le polyedre associe, appelees contraintes de coupes. Ces contraintes sont utilisees par la suite dans une methode de coupes pour resoudre des instances du probleme. Les resultats experimentaux montrent que ces contraintes peuvent etre utiles pour la resolution du probleme dans les graphes peu denses

Beker, Sergio Ariel. "Techniques d'Optimisation pour le Dimensionnement et la Reconfiguration des Réseaux MPLS". Phd thesis, Télécom ParisTech, 2004. http://pastel.archives-ouvertes.fr/pastel-00000689.

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La superposition de topologies virtuelles à la topologie physique d'un réseau est un des principaux mécanismes de l'ingénierie de trafic. Soit un réseau physique d'une certaine topologie et capacité fixées et une matrice de trafic à véhiculer, il s'agit trouver une topologie logique permettant de mapper de manière optimale la matrice de trafic sur le réseau physique. Lors de l'évolution de la matrice de trafic sur des échelles de temps longues, il faudra agir sur le layout. La première contribution concerne la définition de fonctions de coût mieux adaptées à la réalité d'un opérateur, la deuxième contribution concerne la prise en compte du coût de changement du layout. Il s'avère intéressant d'un point de vue opérateur de réduire la complexité du layout, mesurée comme une fonction du nombre de chemins virtuels. Nous avons donc formulé divers problèmes de minimisation de la complexité du layout sous des contraintes de QoS. Il s'agit d'une modélisation réaliste mais qui engendre des modèles difficiles à résoudre. Nous avons développés des heuristiques qui permet de trouver des solutions approchées pour des réseaux de grande taille. Nous avons montré que la complexité des layouts peut être significativement réduite en comparaison avec celle obtenue suite à l'optimisation des fonctions de coût classiques. Le changement du layout implique d'une part un coût d'opération et d'autre part peut engendrer des coupures de service qui affecteront directement le coût d'opération. Nous avons formulé une famille de problèmes prenant en compte le coût de reconfiguration du layout. L'une des heuristiques citées a été adaptée pour analyser ces nouveaux problèmes.

Bonnotte, Nicolas. "Unidimensional and Evolution Methods for Optimal Transportation". Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00946781.

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In dimension one, optimal transportation is rather straightforward. The easiness with which a solution can be obtained in that setting has recently been used to tackle more general situations, each time thanks to the same method. First, disintegrate your problem to go back to the unidimensional case, and apply the available 1D methods to get a first result; then, improve it gradually using some evolution process.This dissertation explores that direction more thoroughly. Looking back at two problems only partially solved this way, I show how this viewpoint in fact allows to go even further.The first of these two problems concerns the computation of Yann Brenier's optimal map. Guillaume Carlier, Alfred Galichon, and Filippo Santambrogio found a new way to obtain it, thanks to an differential equation for which an initial condition is given by the Knothe--Rosenblatt rearrangement. (The latter is precisely defined by a series of unidimensional transformations.) However, they only dealt with discrete target measures; I~generalize their approach to a continuous setting. By differentiation, the Monge--Ampère equation readily gives a PDE satisfied by the Kantorovich potential; but to get a proper initial condition, it is necessary to use the Nash--Moser version of the implicit function theorem.The basics of optimal transport are recalled in the first chapter, and the Nash--Moser theory is exposed in chapter 2. My results are presented in chapter 3, and numerical experiments in chapter 4.The last chapter deals with the IDT algorithm, devised by François Pitié, Anil C. Kokaram, and Rozenn Dahyot. It builds a transport map that seems close enough to the optimal map for most applications. A complete mathematical understanding of the procedure is, however, still lacking. An interpretation as a gradient flow in the space of probability measures is proposed, with the sliced Wasserstein distance as the functional. I also prove the equivalence between the sliced and usual Wasserstein distances.

Sa, Shibasaki Rui. "Lagrangian Decomposition Methods for Large-Scale Fixed-Charge Capacitated Multicommodity Network Design Problem". Thesis, Université Clermont Auvergne‎ (2017-2020), 2020. http://www.theses.fr/2020CLFAC024.

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Typiquement présent dans les domaines de la logistique et des télécommunications, le problème de synthèse de réseau multi-flot à charge fixe reste difficile, en particulier dans des contextes à grande échelle. Dans ce cas, la capacité à produire des solutions de bonne qualité dans un temps de calcul raisonnable repose sur la disponibilité d'algorithmes efficaces. En ce sens, cette thèse propose des approches lagrangiennes capables de fournir des bornes relativement proches de l'optimal pour des instances de grande taille. L'efficacité des méthodes dépend de l'algorithme appliqué pour résoudre les duals lagrangiens, nous choisissons donc entre deux des solveurs les plus efficaces de la littérature: l'algorithme de Volume et la méthode Bundle, fournissant une comparaison entre eux. Les résultats ont montré que l'algorithme de Volume est plus efficace dans le contexte considéré, étant celui choisi pour le développement du projet de recherche.Une première heuristique lagrangienne a été conçue pour produire des solutions réalisables de bonne qualité pour le problème, obtenant de bien meilleurs résultats que Cplex pour les plus grandes instances. Concernant les limites inférieures, un algorithme Relax-and-Cut a été implémenté intégrant une analyse de sensibilité et une mise à l'échelle des contraintes, ce qui a amélioré les résultats. Les améliorations des bornes inférieures ont atteint 11\%, mais en moyenne, elles sont restées inférieures à 1\%. L'algorithme Relax-and-Cut a ensuite été inclus dans un schéma Branch-and-Cut, pour résoudre des programmes linéaires dans chaque nœud de l'arbre de recherche. De plus, une heuristique Feasibility Pump lagrangienne a été implémentée pour accélérer la recherche de bonnes solutions réalisables. Les résultats obtenus ont montré que le schéma proposé est compétitif avec les meilleurs algorithmes de la littérature et fournit les meilleurs résultats dans des contextes à grande échelle. De plus, une version heuristique de l'algorithme Branch-and-Cut basé sur le Feasibility Pump lagrangien a été testée, fournissant les meilleurs résultats en général, par rapport aux heuristiques de la littérature
Typically present in logistics and telecommunications domains, the Fixed-Charge Multicommodity Capacitated Network Design Problem remains challenging, especially when large-scale contexts are involved. In this particular case, the ability to produce good quality soutions in a reasonable amount of time leans on the availability of efficient algorithms. In that sense, the present thesis proposed Lagrangian approaches that are able to provide relatively sharp bounds for large-scale instances of the problem. The efficiency of the methods depend on the algorithm applied to solve Lagrangian duals, so we choose between two of the most efficient solvers in the literature: the Volume Algorithm and the Bundle Method, providing a comparison between them. The results showed that the Volume Algorithm is more efficient in the present context, being the one kept for further research.A first Lagrangian heuristic was devised to produce good quality feasible solutions for the problem, obtaining far better results than Cplex, for the largests instances. Concerning lower bounds, a Relax-and-Cut algorithm was implemented embbeding sensitivity analysis and constraint scaling, which improved results. The increases in lower bounds attained 11\%, but on average they remained under 1\%.The Relax-and-Cut algorithm was then included in a Branch-and-Cut scheme, to solve linear programs in each node of the search tree. Moreover, a Feasibility Pump heuristic using the Volume Algorithm as solver for linear programs was implemented to accelerate the search for good feasible solutions in large-scale cases. The obtained results showed that the proposed scheme is competitive with the best algorithms in the literature, and provides the best results in large-scale contexts. Moreover, a heuristic version of the Branch-and-Cut algorithm based on the Lagrangian Feasibility Pump was tested, providing the best results in general, when compared to efficient heuristics in the literature

Soyez-Martin, Claire. "From semigroup theory to vectorization : recognizing regular languages". Electronic Thesis or Diss., Université de Lille (2022-....), 2023. http://www.theses.fr/2023ULILB052.

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L'évaluation efficace des expressions régulières constitue un défi persistant depuis de nombreuses décennies. Au fil du temps, des progrès substantiels ont été réalisés grâce à une variété d'approches, allant de nouveaux et ingénieux algorithmes à des optimisations complexes de bas niveau.Les outils de pointe de ce domaine utilisent ces techniques d'optimisation, et repoussent constamment les limites de leur efficacité. Une avancée notoire réside dans l'intégration de la vectorisation, qui exploite une forme de parallélisme de bas niveau pour traiter l'entrée par blocs, entraînant ainsi d'importantes améliorations de performances. Malgré une recherche approfondie sur la conception d'algorithmes sur mesure pour des tâches particulières, ces solutions manquent souvent de généralisabilité, car la méthodologie sous-jacente à ces algorithmes ne peut pas être appliquée de manière indiscriminée à n'importe quelle expression régulière, ce qui rend difficile son intégration dans les outils existants.Cette thèse présente un cadre théorique permettant de générer des programmes vectorisés particuliers capables d'évaluer les expressions régulières correspondant aux expressions rationnelles appartenant à une classe logique donnée. L'intérêt de ces programmes vectorisés vient de l'utilisation de la théorie algébrique des automates, qui offre certains outils algébriques permettant de traiter les lettres en parallèle. Ces outils permettent également d'analyser les langages réguliers plus finement, offrent accès à des optimisations des programmes vectorisés basées sur les propriétés algébriques de ces langages. Cette thèse apporte des contributions dans deux domaines. D'une part, nous présentons des implémentations et des benchmarks préliminaires, afin d'étudier les possibilités offertes par l'utilisation de l'algèbre et de la vectorisation dans les algorithmes d'évaluation des expressions régulières. D'autre part, nous proposons des algorithmes capables de générer des programmes vectorisés reconnaissant les langages appartenant à deux classes d'expressions rationnelles, la logique du premier ordre et sa restriction aux formules utilisant au plus deux variables
The pursuit of optimizing regular expression validation has been a long-standing challenge,spanning several decades. Over time, substantial progress has been made through a vast range of approaches, spanning from ingenious new algorithms to intricate low-level optimizations.Cutting-edge tools have harnessed these optimization techniques to continually push the boundaries of efficient execution. One notable advancement is the integration of vectorization, a method that leverage low-level parallelism to process data in batches, resulting in significant performance enhancements. While there has been extensive research on designing handmade tailored algorithms for particular languages, these solutions often lack generalizability, as the underlying methodology cannot be applied indiscriminately to any regular expression, which makes it difficult to integrate to existing tools.This thesis provides a theoretical framework in which it is possible to generate vectorized programs for regular expressions corresponding to rational expressions in a given class. To do so, we rely on the algebraic theory of automata, which provides tools to process letters in parallel. These tools also allow for a deeper understanding of the underlying regular language, which gives access to some properties that are useful when producing vectorized algorithms. The contribution of this thesis is twofold. First, it provides implementations and preliminary benchmarks to study the potential efficiency of algorithms using algebra and vectorization. Second, it gives algorithms that construct vectorized programs for languages in specific classes of rational expressions, namely the first order logic and its subset restricted to two variables

Frery, Jordan. "Ensemble Learning for Extremely Imbalced Data Flows". Thesis, Lyon, 2019. http://www.theses.fr/2019LYSES034.

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L'apprentissage machine est l'étude de la conception d'algorithmes qui apprennent à partir des données d'apprentissage pour réaliser une tâche spécifique. Le modèle résultant est ensuite utilisé pour prédire de nouveaux points de données (invisibles) sans aucune aide extérieure. Ces données peuvent prendre de nombreuses formes telles que des images (matrice de pixels), des signaux (sons,...), des transactions (âge, montant, commerçant,...), des journaux (temps, alertes, ...). Les ensembles de données peuvent être définis pour traiter une tâche spécifique telle que la reconnaissance d'objets, l'identification vocale, la détection d'anomalies, etc. Dans ces tâches, la connaissance des résultats escomptés encourage une approche d'apprentissage supervisé où chaque donnée observée est assignée à une étiquette qui définit ce que devraient être les prédictions du modèle. Par exemple, dans la reconnaissance d'objets, une image pourrait être associée à l'étiquette "voiture" qui suggère que l'algorithme d'apprentissage doit apprendre qu'une voiture est contenue dans cette image, quelque part. Cela contraste avec l'apprentissage non supervisé où la tâche à accomplir n'a pas d'étiquettes explicites. Par exemple, un sujet populaire dans l'apprentissage non supervisé est de découvrir les structures sous-jacentes contenues dans les données visuelles (images) telles que les formes géométriques des objets, les lignes, la profondeur, avant d'apprendre une tâche spécifique. Ce type d'apprentissage est évidemment beaucoup plus difficile car il peut y avoir un nombre infini de concepts à saisir dans les données. Dans cette thèse, nous nous concentrons sur un scénario spécifique du cadre d'apprentissage supervisé : 1) l'étiquette d'intérêt est sous-représentée (p. ex. anomalies) et 2) l'ensemble de données augmente avec le temps à mesure que nous recevons des données d'événements réels (p. ex. transactions par carte de crédit). En fait, ces deux problèmes sont très fréquents dans le domaine industriel dans lequel cette thèse se déroule
Machine learning is the study of designing algorithms that learn from trainingdata to achieve a specific task. The resulting model is then used to predict overnew (unseen) data points without any outside help. This data can be of manyforms such as images (matrix of pixels), signals (sounds,...), transactions (age,amount, merchant,...), logs (time, alerts, ...). Datasets may be defined to addressa specific task such as object recognition, voice identification, anomaly detection,etc. In these tasks, the knowledge of the expected outputs encourages a supervisedlearning approach where every single observed data is assigned to a label thatdefines what the model predictions should be. For example, in object recognition,an image could be associated with the label "car" which suggests that the learningalgorithm has to learn that a car is contained in this picture, somewhere. This is incontrast with unsupervised learning where the task at hand does not have explicitlabels. For example, one popular topic in unsupervised learning is to discoverunderlying structures contained in visual data (images) such as geometric formsof objects, lines, depth, before learning a specific task. This kind of learning isobviously much harder as there might be potentially an infinite number of conceptsto grasp in the data. In this thesis, we focus on a specific scenario of thesupervised learning setting: 1) the label of interest is under represented (e.g.anomalies) and 2) the dataset increases with time as we receive data from real-lifeevents (e.g. credit card transactions). In fact, these settings are very common inthe industrial domain in which this thesis takes place

Gessese, Alelign Fekade. "Algorithms for Bed Topography Reconstruction in Geophysical Flows". Thesis, University of Canterbury. Mechanical Engineering, 2013. http://hdl.handle.net/10092/8673.

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Bed topography identification in open channel and glacier flows is of paramount importance for the study of the respective flows. In the former, the knowledge of the channel bed topography is required for modelling the hydrodynamics of open channel flows, fluvial hydraulics, flood propagation, and river flow monitoring. Indeed, flow models based on the Shallow Water Approximation require prior information on the channel bed topography to accurately capture the flow features. While in the latter, usable bedrock topographic information is very important for glacier flow modellers to accurately predict the flow characteristics. Experimental techniques to infer the bed topography are usually used but are mostly time consuming, costly, and sometimes not possible due to geographical restrictions. However, the measurement of free surface elevation is relatively easy. Alternative to experimental techniques, it is therefore important to develop fast, easy-to-implement, and cost-effective numerical methods. The inverse of the classical hydrodynamic problem corresponds to the determination of hydraulic parameters from measurable quantities. The forward problem uses model parameters to determine measurable quantities. New one-shot and direct pseudo-analytical and numerical approaches for reconstructing the channel bed topography from known free surface elevation data is developed for one-dimensional shallow water flows. It is shown in this work that instead of treating this inverse problem in the traditional partial differential equation (PDE)-constrained optimization framework, the governing equations of the direct problem can be conveniently rearranged to obtain an explicit PDE for the inverse problem. This leads to a direct solution of the inverse problem which is successfully tested on a range of benchmark problems and experimental data for noisy and noiseless free surface data. It was found that this solution approach creates very little amplification of noise. A numerical technique which uses the measured free surface velocity to infer the channel bed topography is also developed. The one-dimensional shallow water equations along with an empirical relationship between the free surface and the depth averaged velocities are used for the inverse problem analysis. It is shown that after a series of algebraic manipulation and integration, the equation governing the inverse problem simplifies to a simple integral equation. The proposed method is tested on a range of analytical and experimental benchmark test cases and the results confirm that, it is possible to reconstruct the channel bed topography from a known free surface velocity distribution of one-dimensional open channel flows. Following the analysis of the case of one-dimensional shallow water flows, a numerical technique for reconstructing the channel bed topography from known free surface elevation data for steep open channel flows is developed using a modified set of equations for which the zero-inertia shallow water approximation holds. In this context, the shallow water equations are modified by neglecting inertia terms while retaining the effects of the bed slope and friction terms. The governing equations are recast into a single first-order partial differential equation which describes the inverse problem. Interestingly, the analysis shows that the inverse problem does not require the knowledge of the bed roughness. The forward problem is solved using MacCormack’s explicit numerical scheme by considering unsteady modified shallow water equations. However, the inverse problem is solved using the method of characteristics. The results of the inverse and the forward problem are successfully tested against each other. In the framework of full two-dimensional shallow water equations, an easy-to-implement and fast to solve direct numerical technique is developed to solve the inverse problem of shallow open channel flows. The main underlying idea is analogous to the idea implemented for the case of one-dimensional reconstruction. The technique described is a “one-shot technique” in the sense that the solution of the partial differential equation provides the solution to the inverse problem directly. The idea is tested on a set of artificial data obtained by first solving the forward problem. Glaciers are very important as an indicator of future climate change or to trace past climate. They respond quickly compared to the Antarctica and Greenland ice sheets which make them ideal to predict climate changes. Glacier bedrock topography is an important parameter in glacier flow modelling to accurately capture its flow dynamics. Thus, a mathematical technique to infer this parameter from measured free surface data is invaluable. Analogous to the approaches implemented for open channel flows, easy-to-implement direct numerical and analytical algorithms are developed to infer the bedrock topography from the knowledge of the free surface elevation in one space dimension. The numerical and analytical methods are both based on the Shallow Ice Approximation and require the time series of the ablation/accumulation rate distribution. Moreover, the analytical method requires the knowledge of a non-zero glacier thickness at an arbitrary location. Numerical benchmark test cases are used to verify the suitability and applicability of the algorithms.

Pervaiz, Mehtab M. "Spatio-temporal adaptive algorithm for reacting flows". Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/34994.

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Libri sul tema "Algorithme de flots":

Ahuja, Ravindra K. Network flows: Theory, algorithms, and applications. Englewood Cliffs, N.J: Prentice Hall, 1993.

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Tidriri, M. D. Schwarz-based algorithms for compressible flows. Hampton, Va: Institute for Computer Applications in Science and Engineering, 1996.

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Ahuja, Ravindra K. Network flows: Theory, algorithms, and applications. Englewood Cliffs, NJ: Prentice Hall, 1993.

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1955-, Bloch Anthony, a cura di. Hamiltonian and gradient flows, algorithms, and control. Providence, RI: American Mathematical Society, 1994.

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Ruhe, Günther. Algorithmic Aspects of Flows in Networks. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3444-6.

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Ruhe, Günther. Algorithmic aspects of flows in networks. Dordrecht: Kluwer Academic Publishers, 1991.

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United States. National Aeronautics and Space Administration., a cura di. An algorithm for unsteady flows with strong convection. [Washington, DC]: National Aeronautics and Space Administration, 1988.

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Hulshoff, Steven John. An Euler solution algorithm for steady helicopter-rotor flows. [Downsview, Ont.]: University of Toronto, Graduate Department of Aerospace Science and Engineering, 1994.

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Oden, J. Tinsley. Vectorizable algorithms for adaptive schemes for rapid analysis of SSME flows: Final report. Austin, Tex: Computational Mechanics Co., Inc., 1987.

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B, Gatski T., e Langley Research Center, a cura di. Efficient parallel algorithm for direct numerical simulation of turbulent flows. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1997.

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Capitoli di libri sul tema "Algorithme de flots":

Jungnickel, Dieter. "Flows". In Graphs, Networks and Algorithms, 155–208. Berlin, Heidelberg: Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-662-03822-2_6.

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Jungnickel, Dieter. "Flows". In Graphs, Networks and Algorithms, 163–218. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-32278-5_6.

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Korte, Bernhard, e Jens Vygen. "Network Flows". In Algorithms and Combinatorics, 173–209. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-24488-9_8.

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Korte, Bernhard, e Jens Vygen. "Network Flows". In Algorithms and Combinatorics, 153–84. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-662-21708-5_8.

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Korte, Bernhard, e Jens Vygen. "Network Flows". In Algorithms and Combinatorics, 153–84. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-662-21711-5_8.

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Korte, Bernhard, e Jens Vygen. "Network Flows". In Algorithms and Combinatorics, 177–214. Berlin, Heidelberg: Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/978-3-662-56039-6_8.

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Hetland, Magnus Lie. "Matchings, Cuts, and Flows". In Python Algorithms, 209–25. Berkeley, CA: Apress, 2014. http://dx.doi.org/10.1007/978-1-4842-0055-1_10.

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Korte, Bernhard, e Jens Vygen. "Minimum Cost Flows". In Algorithms and Combinatorics, 211–39. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-24488-9_9.

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Kao, Ming-Yang. "Atomic Selfish Flows". In Encyclopedia of Algorithms, 77. Boston, MA: Springer US, 2008. http://dx.doi.org/10.1007/978-0-387-30162-4_42.

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Korte, Bernhard, e Jens Vygen. "Minimum Cost Flows". In Algorithms and Combinatorics, 185–204. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-662-21708-5_9.

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Atti di convegni sul tema "Algorithme de flots":

Benke, M., E. Shapiro e D. Drikakis. "FALCO: Fast Linear Corrector for Modelling DNA-Laden Flows". In ASME 2008 6th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2008. http://dx.doi.org/10.1115/icnmm2008-62131.

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The paper concerns the development of a numerical algorithm for improving the efficiency of computational fluid dynamics simulations of transport of biomolecules in microchannels at low number densities. For this problem, the continuum approach based on the concentration field model becomes invalid, whereas time scales involved make purely molecular simulations prohibitively computationally expensive. In this context, meta-models based on coupled solution of fluid flow equations and equations of motion for a simplified mechanical model of biomolecules provide a viable alternative. Meta-models often rely on particle-corrector algorithms, which impose length constraints on the mechanical DNA model. Particle-corrector algorithms are not sufficiently robust, thus resulting in slow convergence. A new geometrical particle corrector algorithm — called FALCO — is proposed in this paper, which significantly improves computational efficiency in comparison with the widely used SHAKE algorithm. It is shown that the new corrector can be related to the SHAKE algorithm by an appropriate choice of Lagrangian multipliers. Validation of the new particle corrector against a simple analytic solution is performed and the improved convergence is demonstrated for a macromolecule motion in a micro-cavity. This work has been supported in part by the European Commission under the 6th Framework Program (Project: DINAMICS, NMP4-CT-2007-026804).

Likhachov, Alexey V., e Valery V. Pickalov. "Three-Dimensional Tomography of Thermal Flows for Limited Angle of View". In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0774.

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Abstract The paper is devoted to the study of 3D-tomography problems of flows with the numerical simulations, when the data being measured in the narrow angle range. The algebraic algorithms and ones based on the Fourier transform properties seem to be more appropriate for the considered case. The following of them have been investigated: ART, MART, MENT, Gerchberg-Papoulis type algorithm (mGP3D), combined algorithms cART and cMART.

Feist, Sofia, Bruno Ferreira e António Leitao. "Collaborative Algorithmic-based Building Information Modelling". In CAADRIA 2017: Protocols, Flows, and Glitches. CAADRIA, 2017. http://dx.doi.org/10.52842/conf.caadria.2017.613.

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Janssen, Patrick. "Evolutionary Urbanism - Exploring Form-based Codes Using Neuroevolution Algorithms". In CAADRIA 2017: Protocols, Flows, and Glitches. CAADRIA, 2017. http://dx.doi.org/10.52842/conf.caadria.2017.303.

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Ma, Yidong, e Weiguo Xu. "Physarealm - A Bio-inspired Stigmergic Algorithm Tool for Form-Finding". In CAADRIA 2017: Protocols, Flows, and Glitches. CAADRIA, 2017. http://dx.doi.org/10.52842/conf.caadria.2017.499.

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Rajesh, A., H. S. Ko e Ken D. Kihm. "Hybrid Approach to Tomographic Reconstruction of Bubbles in Two-Phase Flows Using Genetic Algorithm". In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0770.

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Abstract Main hurdles in the application of genetic algorithms to complex problems are two folds. One is the high computational cost due to their slow convergence rate. The other is to reduce the input parameters of a conventional genetic algorithm as in the case of tomographic reconstruction of bubbles. In our present work great strides have been made to alleviate both the problems by using a Hybrid model of Algebraic Reconstruction Technique (ART), Simplex Method and Genetic Algorithm (GA).

Kamali, R., e S. A. Shekoohi. "Two Algorithms for Solving Coupled Particle Dynamics and Flow Field Equations in Two-Phase Flows". In ASME 2010 8th International Conference on Nanochannels, Microchannels, and Minichannels collocated with 3rd Joint US-European Fluids Engineering Summer Meeting. ASMEDC, 2010. http://dx.doi.org/10.1115/fedsm-icnmm2010-30443.

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Two methods for solving coupled particle dynamics and flow field equations simultaneously by considering fluid-particle interactions to simulate two-phase flow are presented and compared. In many conditions, such as magnetic micro mixers and shooting high velocity particles in fluid, the fluid-particle interactions can not be neglected. In these cases it is necessary to consider fluid-particle interactions and solve the related coupled equations simultaneously. To solve these equations, suitable algorithms should be used to improve convergence speed and solution accuracy. In this paper two algorithms for solving coupled incompressible Navier-Stokes and particle dynamics equations are proposed and their efficiencies are compared by using them in a computer program. The main criterion that is used for comparison is the time they need to converge for a specific accuracy. In the first algorithm the particle dynamics and flow field equations are solved simultaneously but separately. In the second algorithm in each iteration for solving flow field equations, the particle dynamics equation is also solved. Results for some test cases are presented and compared. According to the results the second algorithm is faster than the first one especially when there is a strong coupling between phases.

Sou, Akira, Kosuke Hayashi e Tsuyoshi Nakajima. "Evaluation of Volume Tracking Algorithms for Gas-Liquid Two-Phase Flows". In ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45164.

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Qualitative and quantitative evaluations of volume tracking algorithms such as DA, FLAIR, MARS, CIP and VTEMC were conducted. Wide variety of two-dimensional test problems including (1) a circle transported in simple translation and rotational field, (2) a bubble rising in 45° slanted gravity field, (3) zigzag motion of a bubble in a vertical channel, and (4) a bubble rising in a stagnant liquid in axissymmetric cylindrical coordinate were chosen in the present study. As a result of these tests, the superiority of the cell-centered piecewise linear algorithm with the divergence treatment in operator split and especially with embedded micro cells was confirmed. Applicability of these algorithms to three-dimensional problems has to be examined in the future works.

Chun, Sejong, e Hyu-Sang Kwon. "Use of Wigner-Ville Transformations for Fluid Particles in Laser Doppler Flow Accelerometry". In ASME-JSME-KSME 2011 Joint Fluids Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajk2011-16021.

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Flow acceleration with Lagrangian description is crucial to understanding particle movements in turbulent jet flows or dissipation statistics in isotropic turbulence. Laser Doppler anemometry is regarded as a suitable experimental tool for measuring flow acceleration, because scattering particles generate trajectories in the measurement volume, which process gives rise to flow acceleration at a fixed measuring point with the Lagrangian description. The most useful algorithm for processing Doppler signals is either the quadrature demodulation technique (QDT) or the iterative parametric method (alternatively, the minimization of least squares, LSM) as in the literature. In the present study, another algorithm using the Wigner-Ville transforms (W-V) is introduced to give more accurate estimation of flow acceleration than the QDT or the LSM. Toward this end, five signal-processing algorithms, including the QDT, the LSM, the MC (maximization of correlation), and the W-V, were compared with each other in experiments with an impinging air jet flow with a cylindrical rod and a round free-air jet flow. Mean flow acceleration distribution in the streamwise direction was mainly investigated. Processing speeds for the above-mentioned signal-processing algorithms were checked to find the best algorithm, which has best performance with short processing time. The QDT was found to be an accurate algorithm with short processing time; however, the QDT was found to have limited applications to flows with large acceleration and high SNR. The MC was also found to be a good algorithm with moderate processing speed, which can be useful in flows with low SNR because the MC is an iterative parametric method. The W-V gave the most accurate values for flow acceleration; however, the processing time for this method was the slowest among the signal-processing algorithms.

Rapporti di organizzazioni sul tema "Algorithme de flots":

Andrade, Jose E. Energy-Consistent Multiscale Algorithms for Granular Flows. Fort Belvoir, VA: Defense Technical Information Center, agosto 2014. http://dx.doi.org/10.21236/ada610189.

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Robert Nourgaliev e Mark Christon. Solution Algorithms for Effective-Field Models of Multi-Fluid Flows. Office of Scientific and Technical Information (OSTI), settembre 2012. http://dx.doi.org/10.2172/1058095.

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Kularatne, Dhanushka N., Subhrajit Bhattacharya e M. Ani Hsieh. Computing Energy Optimal Paths in Time-Varying Flows. Drexel University, 2016. http://dx.doi.org/10.17918/d8b66v.

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Autonomous marine vehicles (AMVs) are typically deployed for long periods of time in the ocean to monitor different physical, chemical, and biological processes. Given their limited energy budgets, it makes sense to consider motion plans that leverage the dynamics of the surrounding flow field so as to minimize energy usage for these vehicles. In this paper, we present two graph search based methods to compute energy optimal paths for AMVs in two-dimensional (2-D) time-varying flows. The novelty of the proposed algorithms lies in a unique discrete graph representation of the 3-D configuration space spanned by the spatio-temporal coordinates. This enables a more efficient traversal through the search space, as opposed to a full search of the spatio-temporal configuration space. Furthermore, the proposed strategy results in solutions that are closer to the global optimal when compared to greedy searches through the spatial coordinates alone. We demonstrate the proposed algorithms by computing optimal energy paths around the Channel Islands in the Santa Barbara bay using time-varying flow field forecasts generated by the Regional Ocean Model System. We verify the accuracy of the computed paths by comparing them with paths computed via an optimal control formulation.

Wilson, T. L., B. D. Nichols, C. W. Hirt e L. R. Stein. SOLA-DM: A numerical solution algorithm for transient three-dimensional flows. Office of Scientific and Technical Information (OSTI), febbraio 1988. http://dx.doi.org/10.2172/5228335.

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Montiel, Peter J. Capital Flows: Issues and Policies. Inter-American Development Bank, maggio 2013. http://dx.doi.org/10.18235/0011498.

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This paper presents an analytical overview of recent contributions to the literature on the policy implications of capital flows in emerging and developing countries, focusing specifically on capital inflows as well as on the links between inflows and subsequent capital-flow reversals. The objective is to clarify the policy challenges that such inflows pose and to evaluate the policy alternatives available to the recipient countries to cope with those challenges. A large menu of possible policy responses to large capital inflows is considered, and experience with the use of such policies is reviewed. A policy `decision tree`-i. e. , an algorithm for determining how to deploy policies in response to an exogenous inflow episode- is developed, and strategies to achieve resilience to both inflows and outflows in a world where exogenous events may frequently drive capital flows in both directions are discussed.

Jacobs, Gustaaf B. High-Order Particle-Mesh Algorithms for Computation of Particle-Laden Shocked Flows. Fort Belvoir, VA: Defense Technical Information Center, maggio 2012. http://dx.doi.org/10.21236/ada567598.

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Chung, T. J. Flowfield-Dependent Mixed Explicit-Implicit(FDMEI) Algorithm Toward Direct Numerical Simulation in High Speed Flows. Fort Belvoir, VA: Defense Technical Information Center, luglio 1997. http://dx.doi.org/10.21236/ada329549.

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Williams, P. T. CCM Continuity Constraint Method: A finite-element computational fluid dynamics algorithm for incompressible Navier-Stokes fluid flows. Office of Scientific and Technical Information (OSTI), settembre 1993. http://dx.doi.org/10.2172/10194809.

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Ayoul-Guilmard, Q., F. Nobile, S. Ganesh, M. Nuñez, R. Tosi, C. Soriano e R. Rosi. D5.5 Report on the application of multi-level Monte Carlo to wind engineering. Scipedia, 2022. http://dx.doi.org/10.23967/exaqute.2022.3.03.

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Abstract (sommario):

We study the use of multi-level Monte Carlo methods for wind engineering. This report brings together methodological research on uncertainty quantification and work on target applications of the ExaQUte project in wind and civil engineering. First, a multi-level Monte Carlo for the estimation of the conditional value at risk and an adaptive algorithm are presented. Their reliability and performance are shown on the time-average of a non-linear oscillator and on the lift coefficient of an airfoil, with both preset and adaptively refined meshes. Then, we propose an adaptive multi-fidelity Monte Carlo algorithm for turbulent fluid flows where multilevel Monte Carlo methods were found to be inefficient. Its efficiency is studied and demonstrated on the benchmark problem of quantifying the uncertainty on the drag force of a tall building under random turbulent wind conditions. All numerical experiments showcase the open-source software stack of the ExaQUte project for large-scale computing in a distributed environment.

Lohner, Rainald, e Jean Cabello. Development and Application of New Algorithms for the Simulation of Compressible flows with Moving Bodies in Three Dimensions. Fort Belvoir, VA: Defense Technical Information Center, marzo 1992. http://dx.doi.org/10.21236/ada250232.

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