Bibliographies thématiques / Local/Global minimizers

Littérature scientifique sur le sujet « Local/Global minimizers »

Auteur : Grafiati
Publié le 14 mars 2023

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Articles de revues sur le sujet "Local/Global minimizers"

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Giner, E. « Local minimizers of integral functionals are global minimizers ». Proceedings of the American Mathematical Society 123, no 3 (1 mars 1995) : 755. http://dx.doi.org/10.1090/s0002-9939-1995-1254839-1.

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Jimbo, Shuichi, et Jian Zhai. « Domain perturbation method and local minimizers to Ginzburg-Landau functional with magnetic effect ». Abstract and Applied Analysis 5, no 2 (2000) : 101–12. http://dx.doi.org/10.1155/s1085337500000233.

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We prove the existence of vortex local minimizers to Ginzburg-Landau functional with a global magnetic effect. A domain perturbating method is developed, which allows us to extend a local minimizer on a nonsimply connected superconducting material to the local minimizer with vortex on a simply connected material.
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Andersson, Mats, Oleg Burdakov, Hans Knutsson et Spartak Zikrin. « Global Search Strategies for Solving Multilinear Least-Squares Problems ». Sultan Qaboos University Journal for Science [SQUJS] 16 (1 avril 2012) : 12. http://dx.doi.org/10.24200/squjs.vol17iss1pp12-21.

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The multilinear least-squares (MLLS) problem is an extension of the linear least-squares problem. The difference is that a multilinear operator is used in place of a matrix-vector product. The MLLS is typically a large-scale problem characterized by a large number of local minimizers. It originates, for instance, from the design of filter networks. We present a global search strategy that allows for moving from one local minimizer to a better one. The efficiency of this strategy is illustrated by the results of numerical experiments performed for some problems related to the design of filter networks.
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Rodríguez, Nancy, et Yi Hu. « On the steady-states of a two-species non-local cross-diffusion model ». Journal of Applied Analysis 26, no 1 (1 juin 2020) : 1–19. http://dx.doi.org/10.1515/jaa-2020-2003.

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AbstractWe investigate the existence and properties of steady-state solutions to a degenerate, non-local system of partial differential equations that describe two-species segregation in homogeneous and heterogeneous environments. This is accomplished via the analysis of the existence and non-existence of global minimizers to the corresponding free energy functional. We prove that in the spatially homogeneous case global minimizers exist if and only if the mass of the potential governing the intra-species attraction is sufficiently large and the support of the potential governing the interspecies repulsion is bounded. Moreover, when they exist they are such that the two species have disjoint support, leading to complete segregation. For the heterogeneous environment we show that if a sub-additivity condition is satisfied then global minimizers exists. We provide an example of an environment that leads to the sub-additivity condition being satisfied. Finally, we explore the bounded domain case with periodic conditions through the use of numerical simulations.
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Palatucci, Giampiero, Ovidiu Savin et Enrico Valdinoci. « Local and global minimizers for a variational energy involving a fractional norm ». Annali di Matematica Pura ed Applicata 192, no 4 (4 janvier 2012) : 673–718. http://dx.doi.org/10.1007/s10231-011-0243-9.

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Porretta, Alessio. « On the regularity of the total variation minimizers ». Communications in Contemporary Mathematics 23, no 01 (20 novembre 2019) : 1950082. http://dx.doi.org/10.1142/s0219199719500822.

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We prove regularity results for the unique minimizer of the total variation functional, currently used in image processing analysis since the work by Rudin, Osher and Fatemi. In particular, we show that if the source term [Formula: see text] is locally (respectively, globally) Lipschitz, then the solution has the same regularity with local (respectively, global) Lipschitz norm estimated accordingly. The result is proved in any dimension and for any (regular) domain. So far we extend a similar result proved earlier by Caselles, Chambolle and Novaga for dimension [Formula: see text] and (in case of the global regularity) for convex domains.
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Teughels, Anne, Guido De Roeck et Johan A. K. Suykens. « Global optimization by coupled local minimizers and its application to FE model updating ». Computers & ; Structures 81, no 24-25 (septembre 2003) : 2337–51. http://dx.doi.org/10.1016/s0045-7949(03)00313-4.

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AZORERO, J. P. GARCÍA, I. PERAL ALONSO et JUAN J. MANFREDI. « SOBOLEV VERSUS HÖLDER LOCAL MINIMIZERS AND GLOBAL MULTIPLICITY FOR SOME QUASILINEAR ELLIPTIC EQUATIONS ». Communications in Contemporary Mathematics 02, no 03 (août 2000) : 385–404. http://dx.doi.org/10.1142/s0219199700000190.

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Enkhbat, R., et T. Bayartugs. « Quasiconvex Semidefinite Minimization Problem ». Journal of Optimization 2013 (2013) : 1–6. http://dx.doi.org/10.1155/2013/346131.

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We introduce so-called semidefinite quasiconvex minimization problem. We derive new global optimality conditions for the above problem. Based on the global optimality conditions, we construct an algorithm which generates a sequence of local minimizers which converge to a global solution.
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Duboscq, Romain, et Olivier Pinaud. « On local quantum Gibbs states ». Journal of Mathematical Physics 63, no 10 (1 octobre 2022) : 102102. http://dx.doi.org/10.1063/5.0058574.

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We address in this work the problem of minimizing quantum entropies under local constraints. We suppose that macroscopic quantities, such as the particle density, current, and kinetic energy, are fixed at each point of [Formula: see text] and look for a density operator over [Formula: see text], minimizing an entropy functional. Such minimizers are referred to as local Gibbs states. This setting is in contrast with the classical problem of prescribing global constraints, where the total number of particles, total current, and total energy in the system are fixed. The question arises, for instance, in the derivation of fluid models from quantum dynamics. We prove, under fairly general conditions, that the entropy admits a unique constrained minimizer. Due to a lack of compactness, the main difficulty in the proof is to show that limits of minimizing sequences satisfy the local energy constraint. We tackle this issue by introducing a simpler auxiliary minimization problem and by using a monotonicity argument involving the entropy.
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Thèses sur le sujet "Local/Global minimizers"

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Luo, Tingjian. « Existence non existence et multiplicité d'ondes stationnaires normalisées pour quelques équations non linéaires elliptiques ». Phd thesis, Université de Franche-Comté, 2013. http://tel.archives-ouvertes.fr/tel-01061670.

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Dans cette thèse, nous étudions l'existence, non existence et multiplicité des ondes stationnairesavec les normes prescrites pour deux types d'équations aux dérivées partiellesnon linéaires elliptiques découlant de différents modèles physiques. La stabilité orbitale desondes stationnaires est également étudiée dans certains cas. Les principales méthodes denos preuves sont des arguments variationnels. Les solutions sont obtenues comme pointscritiques de fonctionnelle associée sur une contrainte.La thèse se compose de sept chapitres. Le Chapitre 1 est l'introduction de la thèse. Dansles Chapitres 2 à 4, nous étudions une classe d'équations de Schrödinger-Poisson-Slaternon linéaires. Nous établissons dans le Chapitre 2 des résultats optimaux non existencede solutions d'énergie minimale ayant une norme L2 prescrite. Dans le Chapitre 3, nousmontrons un résultat d'existence de solutions L2 normalisées, dans une cas où la fonctionnelleassociée n'est pas bornée inférieurement sur la contrainte. Nos solutions sonttrouvées comme des points de selle de la fonctionnelle, mais ils correspondent à des solutionsd'énergée minimale. Nous montrons également que les ondes stationnaires associéessont orbitalement instables. Ici, puisque nos points critiques présumés ne sont pas desminimiseurs globaux, il n'est pas possible d'utiliser de façon systématique les méthodesde compacité par concentration développées par P. L. Lions. Ensuite, dans le Chapitre4, nous montrons que sous les hypothèses du Chapitre 3, il existe une infinité de solutionsayant une norme L2 prescrite. Dans les deux chapitres suivants, nous étudions uneclasse d'équations de Schrödinger quasi-linéaires. Des résultats optimaux non existence desolutions d'énergie minimale sont donnés dans le Chapitre 5. Dans le Chapitre 6, nousprouvons l'existence de deux solutions positives ayant une norme donnée. L'une d'elles,relativement à la contrainte L2, est de type point selle. L'autre est un minimum, soit localou global. Le fait que la fonctionnelle naturelle associée à cette équation n'est pas biendéfinie nécessite l'utilisation d'une méthode de perturbation pour obtenir ces deux pointscritiques. Enfin, au Chapitre 7, nous mentionnons quelques questions que cette thèse asoulevées.
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Livres sur le sujet "Local/Global minimizers"

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Budolfson, Mark. Food, the Environment, and Global Justice. Sous la direction de Anne Barnhill, Mark Budolfson et Tyler Doggett. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780199372263.013.4.

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This chapter identifies and critically examines a standard form of argument for organic and vegan alternatives to industrial agriculture. This argument faces important objections to its empirical premises, to its presumption that there is a single food system that minimizes harm and is best for the environment, and to the presumption that the ethically best food system for us to promote is the one that would be best in ideal theory or the one that would be best from the perspective of our own society. Instead, determining which food system should be promoted arguably requires a complex global, empirical, and ethical integrated assessment that includes a proper accounting for values of global justice in nonideal theory. This proper accounting arguably recommends sustainable intensification of food systems (as it is called in the food-science literature), which is importantly distinct from contemporary systems as well as from organic, local, and/or vegan-centered alternatives.
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Martinez Machain, Carla, Michael A. Allen, Michael E. Flynn et Andrew Stravers. Beyond the Wire. Oxford University PressNew York, 2022. http://dx.doi.org/10.1093/oso/9780197633403.001.0001.

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Abstract The book studies how U.S. military deployments abroad serve as a tool of public diplomacy that can both support and undermine the international liberal order established by the United States. It develops and systematically tests a theory of public opinion toward the United States, its people, and its global non-invasion military deployments. Positive interactions with servicemembers, including routine daily interactions and the economic flows from a deployment, serve as a form of public diplomacy, improving perceptions of military deployments and the United States as a whole. However, negative events and experiences stemming from deployments, like crime, pollution, and controversial mission types can produce negative reactions among local populations. The book explores these subjects, including chapters devoted to understanding how different forms of contact, reported experiences with crimes involving US service members, and belonging to minority communities, all affect views of the US military presence in a state. We The book also looks at how these factors shape reported involvement in protests against the US, and broader trends in anti-US protest events around the world. The book argues that curtailing servicemember engagement in the community is a policy that can backfire on the US military's long-term objectives, as removing day-to-day positive social interactions with US personnel diminishes one of the main sources of goodwill toward US deployments. It proposes that US policy should focus not on isolating deployed forces from local populations but on regulating interactions in a way that maximizes the potential for beneficial social connections and minimizes harm to host populations.
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Chapitres de livres sur le sujet "Local/Global minimizers"

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Elsener, Andreas, et Sara van de Geer. « Oracle Inequalities for Local and Global Empirical Risk Minimizers ». Dans Applied and Numerical Harmonic Analysis, 211–36. Cham : Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-319-73074-5_7.

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Hoang, Linh, Jung-Tae Lee, Young-In Song et Hae-Chang Rim. « Combining Local and Global Resources for Constructing an Error-Minimized Opinion Word Dictionary ». Dans PRICAI 2008 : Trends in Artificial Intelligence, 688–97. Berlin, Heidelberg : Springer Berlin Heidelberg, 2008. http://dx.doi.org/10.1007/978-3-540-89197-0_63.

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Hammler, Patric, Nicolas Riesterer, Gang Mu et Torsten Braun. « Multi-Echelon Inventory Optimization Using Deep Reinforcement Learning ». Dans Quantitative Models in Life Science Business, 73–93. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-11814-2_5.

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AbstractIn this chapter, we provide an overview of inventory management within the pharmaceutical industry and how to model and optimize it. Inventory management is a highly relevant topic, as it causes high costs such as holding, shortage, and reordering costs. Especially the event of a stock-out can cause damage that goes beyond monetary damage in the form of lost sales. To minimize those costs is the task of an optimized reorder policy. A reorder policy is optimal when it minimizes the accumulated cost in every situation. However, finding an optimal policy is not trivial. First, the problem is highly stochastic as we need to consider variable demands and lead times. Second, the supply chain consists of several warehouses incl. the factory, global distribution warehouses, and local affiliate warehouses, whereby the reorder policy of each warehouse has an impact on the optimal reorder policy of related warehouses. In this context, we discuss the concept of multi-echelon inventory optimization and a methodology that is capable of capturing both, the stochastic behavior of the environment and how it is impacted by the reorder policy: Markov decision processes (MDPs). On this basis, we introduce the concept, its related benefits and weaknesses of a methodology named Reinforcement Learning (RL). RL is capable of finding (near-) optimal (reorder) policies for MDPs. Furthermore, some simulation-based results and current research directions are presented.
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Teughels, A., G. De Roeck et J. A. K. Suykens. « Coupled Local Minimizers : a new global optimization method ». Dans Reliability and Optimization of Structural Systems, 205–12. CRC Press, 2020. http://dx.doi.org/10.1201/9781003078876-25.

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Ko, J., Y. Ni et W. Liao. « Cable force identification by global optimization using coupled local minimizers ». Dans World Forum on Smart Materials and Smart Structures Technology. CRC Press, 2008. http://dx.doi.org/10.1201/9781439828441.ch118.

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Vadim, Kaloshin, et Zhang Ke. « Generic properties of mechanical systems on the two-torus ». Dans Arnold Diffusion for Smooth Systems of Two and a Half Degrees of Freedom, 147–61. Princeton University Press, 2020. http://dx.doi.org/10.23943/princeton/9780691202525.003.0013.

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This chapter focuses on proving generic properties of the minimizing orbits of the slow mechanical system. It first proves Theorem 4.5 concerning non-critical but bounded energy, before proving Proposition 4.6 concerning the very high energy. The chapter then proves Proposition 4.7 concerning the critical energy. The proof of Theorem 4.5 consists of three steps. The first proves a Kupka-Smale-like theorem about non-degeneracy of periodic orbits. The second shows that a non-degenerate locally minimal orbit is always hyperbolic. The third finishes the proof by proving the finite local families obtained from the second step are “in general position,” and therefore there are at most two global minimizers for each energy.
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Oeda, Kaito, Yuusuke Kawakita, Akihito Taya, Yoshito Tobe, Shinji Yokogawa et Haruhisa Ichikawa. « Controlling Power Supply Paths in VG Hub Networks Using a Hybrid Type Control Algorithm ». Dans Ambient Intelligence and Smart Environments. IOS Press, 2022. http://dx.doi.org/10.3233/aise220043.

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Although we have been developing a Virtual Grid (VG) system, where USB-PD-connected devices can alternatively provide and receive electrical power, we have not investigated the desirable power paths in a multiple-VG-Hub network. Our previous study shows that a power loss occurred inside the VG Hub. To minimize the total power loss, the number of used links needs to be minimized; the total power flow in the VG Hub network is minimized. In this paper, we have designed and implemented a cloud-based control system to execute the optimization with preceding local optimization. The experiment result has shown that the proposed hybrid type control algorithm can find the solution in 40% of the computational time on average compared with the algorithm that performs global optimization every time in the network where the solution can be found locally.
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Kim, Minjeong, et Rachelle J. Brunn-Bevel. « Political Economy and the Global-Local Nexus of Hollywood ». Dans Racialized Media, 21–40. NYU Press, 2020. http://dx.doi.org/10.18574/nyu/9781479811076.003.0002.

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Applying a political economy lens to image production suggests that the US film industry, namely, Hollywood, prioritizes financial considerations over racial justice and equity. Decisions made in the production and marketing processes aim to minimize financial risks, but they often limit the participation of filmmakers and actors of color. At the same time, Hollywood incorporates foreign-born directors and actors to entice international audiences. This chapter assesses how Hollywood “going global” impacts local racial-ethnic politics in the US film industry. The authors closely examine films from the past two decades in which people of color constitute the majority of the cast or films in which nonwhites are the lead actors. The authors argue that the incorporation of foreign-born directors and actors inadvertently undermines the efforts of US filmmakers of color to tell cinematic narratives from a critical perspective. Concurrently, Hollywood fails to promote Black films and Black actors on the basis of the assumption that they cannot appeal to international audiences, even though Black films directed by Black directors perform well domestically and show great potential for international success with proper support from Hollywood.
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Bieliková, Hana, et Zuzana Palenčíková. « Sustainable Tourism Development in Times of the COVID-19 Pandemic ». Dans Handbook of Research on the Impacts and Implications of COVID-19 on the Tourism Industry, 823–42. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-8231-2.ch040.

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The COVID-19 acute respiratory syndrome pandemic completely stopped global tourism. Many countries have responded quickly to the situation with a package of measures to help minimize the negative effects of the pandemic on tourism. These impacts are negatively perceived by local population of examined areas which may lead to either uncontrollable tourism development or to dislike of locals in tourism development. Sustainable rural development index for years of 2019 and 2020 was calculated in order to define whether tourism development is under the limits of sustainability. To help to understand the development of tourism and the impact of the COVID-19 pandemic, a SWOT analysis was conducted.
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Karagöz, Berkan. « The Local Government Economics in Globalization Process ». Dans Advances in Finance, Accounting, and Economics, 74–90. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-7564-1.ch005.

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The global economic and social actors are restructuring both private production and public production patterns. This change process is called globalization. The globalization process brings new opportunities with it. One of these opportunities is to increase the efficiency of the local government economics in public finance. The processes of globalization and localization are twin processes and are progressing simultaneously. With globalization, international capital wants to minimize the nation state and to communicate with local governments themselves. In this context, becoming a member of a local government gets ahead of being a nation-state citizen. In the globalization process, existing public goods productions are trying to simulate the market. Such efforts require the public economy to adapt to the market and such adaptation is characteristic of the local government economics itself. International capital, on the other hand, sees central government as a force to be overcome and wants to establish first-hand commercial relations with the local units.
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Actes de conférences sur le sujet "Local/Global minimizers"

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Deshpande, Abhishek, Hassan Khan, Fahad Mirza et Dereje Agonafer. « Global-local finite element optimization study to minimize BGA damage under thermal cycling ». Dans 2014 IEEE Intersociety Conference on Thermal and Thermomechanical Phenomena in Electronic Systems (ITherm). IEEE, 2014. http://dx.doi.org/10.1109/itherm.2014.6892321.

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Gao, Meilin, Bo Ai, Yong Niu, Wen Wu, Peng Yang, Feng Lyu et Xuemin Shen. « Edge Caching and Content Delivery with Minimized Delay for Both High-Speed Train and Local Users ». Dans GLOBECOM 2019 - 2019 IEEE Global Communications Conference. IEEE, 2019. http://dx.doi.org/10.1109/globecom38437.2019.9013389.

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Boutiche, Yamina. « Fast algorithm to minimize model combining dynamically local and global fitting energy for image segmentation ». Dans 2015 3rd International Conference on Control, Engineering & Information Technology (CEIT). IEEE, 2015. http://dx.doi.org/10.1109/ceit.2015.7232985.

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L. Neto, Manoel S., Marly G. F. Costa et Cícero F. F. C. Filho. « A New Global-Local Approach to Optimize School Meals Delivery ». Dans XLIV Seminário Integrado de Software e Hardware. Sociedade Brasileira de Computação - SBC, 2017. http://dx.doi.org/10.5753/semish.2017.3366.

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This paper proposes a hybrid approach to solve the capacitated vehicle routing problem with time window constraints (CVRPTW). In order to evaluate such approach, we propose a case study with the primary goal of defining the delivery routes of school meals in the public school system of Manaus city (Amazonas - Brazil). The optimized solution minimizes the traveled distance of the delivery vehicle and takes into account the capacity and time window time constrains. The approach present in this paper is classified as global-local. On one hand, the metaheuristic simulated annealing, usingthe swap operator, is applied in the global search. On the other hand, A* search algorithm is applied in the local search, in order to refine all solutions presented by the global search. Importantly, the main difference between such approach and the remaining ones present in the literature is that all solutions from the global search are optimized in the local search. The experimental evaluation compares the results with another approach, which will be presented throughout the paper, by means of computation time and total traveled distance.
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Chung, C. L., et S. Desa. « A Global Approach for Using Kinematic Redundancy to Minimize Base Reactions of Manipulators ». Dans ASME 1989 Design Technical Conferences. American Society of Mechanical Engineers, 1989. http://dx.doi.org/10.1115/detc1989-0138.

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Abstract An important consideration in the use of manipulators in Microgravity environments is the minimization of the base reactions, i.e. the magnitude of the force and the moment exerted by the manipulator on its base as it performs its tasks. One approach which has been proposed and implemented is to use the redundant degrees of freedom in a kinematically redundant manipulator to plan manipulator trajectories to minimize base reactions. In this paper we develop a global approach for minimizing the magnitude of the base reactions for kinematically redundant manipulators which integrates the Partitioned Jacobian method of redundancy resolution, a 4-3-4 joint-trajectory representation and the minimization of a cost function which is the time-integral of the magnitude of the base reactions. We also compare the global approach with a local approach developed earlier for the case of point-to-point motion of a three degree-of-freedom planar manipulator with one redundant degree-of-freedom. The results of study show that the global approach is more effective in reducing and smoothing the base force while the local approach is superior in reducing the base moment.
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Scolavino, L., S. Beretta, M. Madia et U. Zerbst. « Critical Speed of Flawed Rotors : Global vs Local Approach ». Dans ASME Turbo Expo 2014 : Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/gt2014-26881.

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The burst of a disc in rotating machinery can cause catastrophic damage of the equipment and, more importantly, it can represent a mortal threat to anyone in the sphere of influence of the event. In order to minimize the danger associated to a rotating component failure, burst testing is required by the authorities in order to set safety margins to the normal operating speeds. Moreover more accurate predicting tools are required for designing the components. This paper presents the results of a numerical and analytical study on the assessment of the crack driving force for discs containing surface flaws. The aim is to provide a simple, though reliable, tool in order to be able to calculate the possible dangerous in-service speed for a rotating component and, therefore, to set burst margins above the normal operating conditions of the equipment. An R6-like flaw assessment procedure is adopted considering different assumptions in the definition of the critical speed and the analytical predictions are compared with the results of elastic-plastic finite element analysis of disc. In particular, the validity and potentiality of the method is proved for surface flaws in different positions in the disc.
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Wang, Eric, Il-Kyu Hwang et Yong Se Kim. « Integrated Local and Global Tool Path Planning for Feature-Based Machining ». Dans ASME 2000 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/detc2000/cie-14646.

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Abstract We describe an automatic machining tool path generation method that combines local tool path planning for machining features with global tool path planning. From the solid model and the tolerance specifications of the part, machining features are automatically recognized, and geometry-based precedence relations are obtained between these features. From this information, the machining sequence, tool selections, and machining conditions are determined. Machining tool paths are then generated automatically for each setup, combining local and global tool paths. Local tool paths to machine each feature are generated using successive offsetting operations. Global tool paths between features are generated incrementally by searching the adjacency graph of feature free spaces, which represents the current free space of the part. Feature free spaces are obtained by expanding the machining features through their fictitious faces. The start and end positions for the local tool paths of each feature are selected based on a heuristic method to minimize the cost of each segment of the global tool path. This automatic tool path generation method is currently being developed as part of a comprehensive machining process planning system.
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Edigbue, Paul, Ismail Demirci, Hamdan Hamdan, Abdullatif Al-Shuhail, Irfan Akca, Pantelis Soupios et Emin Candansayar. « Joint Inversion of Seismic and DC Geophysical Data Using Local and Global Optimization Algorithms ». Dans International Petroleum Technology Conference. IPTC, 2022. http://dx.doi.org/10.2523/iptc-21877-ms.

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Abstract Geophysical inversion is usually carried out to quantitatively analyze the earth model and estimate its physical properties. Successful delineation of these properties such as layer boundaries, or other near-surface structures are crucial to understand the near-surface inhomogeneity. In this study, we focus on the use of joint inversion of seismic refraction and geoelectrical resistivity datasets using local and global optimization methods. The idea is to integrate the two optimization techniques to minimize the challenges faced by each algorithm when applied alone. This hybrid algorithm (local and global) is applied on synthetic data representing simple resistivity and velocity models. About 70% of the anomalies in both seismic and DC resistivity methods were reconstructed in terms of amplitude and geometry using the local optimization algorithm, while the global optimization algorithm shows improved results as it reconstructed about 80% of the amplitude and geometry of the anomalies in both geophysical methods. The result of the synthetic application shows that the hybrid algorithm provides promising outputs in terms of resolution, geometry and amplitude of the anomalies, and computation run time.
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Hsiung, Ching-Kuo, et Mohamed E. M. El-Sayed. « Two-Level Structural Optimization Method for Multi-Processor Environment ». Dans ASME 1990 Design Technical Conferences. American Society of Mechanical Engineers, 1990. http://dx.doi.org/10.1115/detc1990-0069.

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Abstract In this paper a two-level structural optimization approach is presented. At the first level, the objective of the optimization problem is to minimize the total weight of the whole structure subject to the global constraints. At the second level, the optimization problem is divided into several subproblems, each subproblem represents a substructure. The objective of each subproblem is to minimize the weight of the assigned substructure subject to its local constraints. To assure that the final solution will not violate the global constraints, the optimum values of the design variables from the first level are used to update the lower bounds on these variables at the second level. Two numerical examples are included to demonstrate the approach and its application in a multi-processor environment.
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Jun, Cha-Soo, Yuan-Shin Lee et Kyungduck Cha. « Configuration-Space Searching and Optimizing Tool Orientations for 5-Axis Machining ». Dans ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-33598.

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This paper presents a methodology and algorithms of optimizing and smoothing the tool orientation control for 5-axis sculptured surface machining. A searching method in the machining configuration space (C-space) is proposed to find the optimal tool orientation by considering the local gouging, rear gouging and global tool collision in machining. Based on the machined surface error analysis, a boundary search method is developed first to find a set of feasible tool orientations in the C-space to eliminate gouging and collision. By using the minimum cusp height as the objective function, we first determine the locally optimal tool orientation in the C-space to minimize the machined surface error. Considering the adjacent part geometry and the alternative feasible tool orientations in the C-space, tool orientations are then globally optimized and smoothed to minimize the dramatic change of tool orientation during machining. The developed method can be used to automate the planning and programming of tool path generation for high performance 5-axis sculptured surface machining. Computer implementation and examples are also provided in the paper.
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