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Bibliografias temáticas / Level repulsion

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Literatura científica selecionada sobre o tema "Level repulsion"

Autor: Grafiati

Publicado: 8 de fevereiro de 2025

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Artigos de revistas sobre o assunto "Level repulsion"

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MA, TAO, e R. A. SEROTA. "LEVEL REPULSION IN INTEGRABLE SYSTEMS". International Journal of Modern Physics B 26, n.º 13 (5 de maio de 2012): 1250095. http://dx.doi.org/10.1142/s0217979212500956.

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We provide evidence that level repulsion in semiclassical spectrum is not just a feature of classically chaotic systems, but classically integrable systems as well. While in chaotic systems level repulsion develops on a scale of the mean level spacing, regardless of the location in the spectrum, in integrable systems it develops on a much longer scale — such as geometric mean of the mean level spacing and the running energy in the spectrum for hard wall billiards. We show that at this scale level correlations in integrable systems have a universal dependence on the level separation, as well as discuss their exact form at any scale. These correlations have dramatic consequences, including deviations from the Poissonian statistics in the nearest level spacing distribution and persistent oscillations of the level number variance over an energy interval as a function of the interval width. We illustrate our findings on two specific models — rectangular infinite well and a modified Kepler problem — that serve as generic types of a hard wall billiard and a potential problem without extra symmetries. Our theory and numerical work are based on the concept of parametric averaging that allows sampling of a statistical ensemble of integrable systems at a given spectral location (running energy).

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Wan, Qingyun, Jun Yang, Wai-Pong To e Chi-Ming Che. "Strong metal–metal Pauli repulsion leads to repulsive metallophilicity in closed-shell d8 and d10 organometallic complexes". Proceedings of the National Academy of Sciences 118, n.º 1 (28 de dezembro de 2020): e2019265118. http://dx.doi.org/10.1073/pnas.2019265118.

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Metallophilicity is defined as the interaction among closed-shell metal centers, the origin of which remains controversial, particularly for the roles of spd orbital hybridization (mixing of the spd atomic orbitals of the metal atom in the molecular orbitals of metal complex) and the relativistic effect. Our studies reveal that at close M–M′ distances in the X-ray crystal structures of d8 and d10 organometallic complexes, M–M′ closed-shell interactions are repulsive in nature due to strong M–M′ Pauli repulsion. The relativistic effect facilitates (n + 1)s-nd and (n + 1)p-nd orbital hybridization of the metal atom, where (n + 1)s-nd hybridization induces strong M–M′ Pauli repulsion and repulsive M–M′ orbital interaction, and (n + 1)p-nd hybridization suppresses M–M′ Pauli repulsion. This model is validated by both DFT (density functional theory) and high-level coupled-cluster singles and doubles with perturbative triples computations and is used to account for the fact that the intermolecular or intramolecular Ag–Ag′ distance is shorter than the Au–Au′ distance, where a weaker Ag–Ag′ Pauli repulsion plays an important role. The experimental studies verify the importance of ligands in intermolecular interactions. Although the M–M′ interaction is repulsive in nature, the linear coordination geometry of the d10 metal complex suppresses the L–L′ (ligand–ligand) Pauli repulsion while retaining the strength of the attractive L–L′ dispersion, leading to a close unsupported M–M′ distance that is shorter than the sum of the van der Waals radius (rvdw) of the metal atoms.

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Scharf, R., B. Dietz, M. Kuś, F. Haake e M. V. Berry. "Kramers' Degeneracy and Quartic Level Repulsion". Europhysics Letters (EPL) 5, n.º 5 (1 de março de 1988): 383–89. http://dx.doi.org/10.1209/0295-5075/5/5/001.

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Ma, Jian-Zhong. "On the degree of level repulsion". Physics Letters A 207, n.º 5 (novembro de 1995): 269–73. http://dx.doi.org/10.1016/0375-9601(95)00726-j.

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Müller, M., F. M. Dittes, W. Iskra e I. Rotter. "Level repulsion in the complex plane". Physical Review E 52, n.º 6 (1 de dezembro de 1995): 5961–73. http://dx.doi.org/10.1103/physreve.52.5961.

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Sacha, Krzysztof, e Jakub Zakrzewski. "Driven Rydberg Atoms Reveal Quartic Level Repulsion". Physical Review Letters 86, n.º 11 (12 de março de 2001): 2269–72. http://dx.doi.org/10.1103/physrevlett.86.2269.

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Frank, Winfried, e Peter von Brentano. "Classical analogy to quantum mechanical level repulsion". American Journal of Physics 62, n.º 8 (agosto de 1994): 706–9. http://dx.doi.org/10.1119/1.17500.

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Garrett, J. D., J. Q. Robinson, A. J. Foglia e H. Q. Jin. "Nuclear level repulsion and order vs. chaos". Physics Letters B 392, n.º 1-2 (janeiro de 1997): 24–29. http://dx.doi.org/10.1016/s0370-2693(96)01528-6.

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Heiss, W. D. "Phases of wave functions and level repulsion". European Physical Journal D - Atomic, Molecular and Optical Physics 7, n.º 1 (1 de agosto de 1999): 1–4. http://dx.doi.org/10.1007/s100530050339.

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Caurier, E., e B. Grammaticos. "Extreme level repulsion for chaotic quantum Hamiltonians". Physics Letters A 136, n.º 7-8 (abril de 1989): 387–90. http://dx.doi.org/10.1016/0375-9601(89)90420-9.

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Mais fontes

Teses / dissertações sobre o assunto "Level repulsion"

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Iskra, Wlodzimierz, Markus Müller, Ingrid Rotter e Frank-Michael Dittes. "Level repulsion in the complex plane". Forschungszentrum Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:d120-qucosa-32095.

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Iskra, Wlodzimierz, Markus Müller, Ingrid Rotter e Frank-Michael Dittes. "Level repulsion in the complex plane". Forschungszentrum Rossendorf, 1995. https://hzdr.qucosa.de/id/qucosa%3A22036.

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Bourcin, Guillaume. "Spincavitronics : repulsive and attractive energy levels in YIG bulk-microwave cavity coupled systems". Electronic Thesis or Diss., Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2024. http://www.theses.fr/2024IMTA0447.

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Cette thèse explore le domaine de la spincavitronique, en se concentrant sur le couplage fort entre les magnons et les photons dans des cavités tridimensionnelles (3D), conduisant à la formation de polaritons magnons-cavité (CMPs). Nous étudions la transition entre les régimes de couplage fort et ultra-fort, atteignant des forces de couplage de 12 % à 58 % de la fréquence de la cavité à température ambiante. Les magnons, avec leurs fréquences ajustables et leurs longs temps de cohérence, sont des candidats prometteurs pour la mémoire quantique et d'autres technologies quantiques, avec des applications dans le calcul et la communication quantiques. Nos recherches approfondissent la compréhension des interactions magnon-photon, avec des implications pour l’optimisation des systèmes hybrides quantiques. Ce travail présente également une étude du phénomène d'attraction de niveaux entre magnons et modes photoniques d'antirésonance dans des cavités 3D. Ce phénomène permet la transmission non réciproque des photons, essentielle pour des dispositifs tels que les circulateurs et les systèmes de mémoire quantique. Nous développons un modèle physique pour expliquer ces antirésonances, validé par des mesures expérimentales et des simulations. Ces résultats ouvrent de nouvelles perspectives pour l’utilisation des mécanismes d'attraction de niveaux dans les technologies de détection et d'information quantique
This thesis investigates the field of spincavitronics, focusing on the strong coupling between magnons and photons in three-dimensional (3D) cavities, leading to the formation of cavity magnon polaritons (CMPs). We explore the transition between the strong coupling and ultra-strong coupling regimes, achieving coupling strengths between 12% and 58% of the cavity frequency at room temperature. Magnons, with their tunable frequencies and long coherence times, are promising candidates for quantum memory and other quantum technologies, offering applications in quantum computing and long-distance quantum communication. Our research contributes to the development of a deeper understanding of magnon-photon interactions, with implications for improving the coupling strength and optimizing hybrid quantum systems. Additionally, this work presents a detailed study of the level attraction phenomenon between magnons and antiresonant photonic modes in 3D cavities. This phenomenon enables non-reciprocal photon transmission, which is essential for the design of advanced communication devices such as circulators and quantum memory systems. We develop a physical model to explain the emergence of these antiresonances, supported by experimental validation and simulations. These insights open new pathways for applying level attraction mechanisms in sensing technologies and quantum information processing, demonstrating the versatility of spincavitronics for future advancements in both quantum technologies and radiofrequency applications

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Medina, Tulio Eduardo Restrepo. "Geração radiativa de repulsão vetorial para quarks leves". reponame:Repositório Institucional da UFSC, 2014. https://repositorio.ufsc.br/xmlui/handle/123456789/129306.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Física, Florianópolis, 2014
Made available in DSpace on 2015-02-05T20:56:09Z (GMT). No. of bitstreams: 1 330269.pdf: 2723044 bytes, checksum: acc5bb1f16ab0d07a08b676e16f1ea63 (MD5) Previous issue date: 2014
Abstract: We apply a non-perturbative analytical method, known as the Optimized PerturbationTheory (OPT), to the Polyakov-Nambu-Jona-Lasinio (PNJL) model in order to investigate physical quantities associated with the QCD phase transitions. We consider the Taylor expansion of the pressure in powers of µ/T obtaining the second cumulant (c2) which is associated to the quark number susceptibility. We discuss how the OPT nite Nc radiative (quantum) corrections induce a contribution to the pressure which behaves as a vector repulsion even when such a channel is absent in the original classical potential. Our results are then compared with the ones furnished by lattice QCD simulations and by the large-Nc approximation showing that, physically, the OPT results resemble those furnished by the latter approximation when a repulsive vector channel is explicitly included in the classical potential. In this case, both approximations fail to correctly describe the Stefan-Boltzmann limit at high temperatures. We discuss how this problem can be circumvented by taking the couplings to be temperature dependent so as to simulate the phenomenon of asymptotic freedom. Since this is the first time the OPT is applied to the PNJL we also discuss many technicalities associated with the evaluation of two loop (exchange) diagrams.

Neste trabalho o método analítico não perturbativo conhecido como Teoria de Perturbação Otimizada (OPT) é aplicada ao modelo de Polyakov-Nambu-Jona-Lasinio (PNJL) para que quantidades físicas, associadas com as transições de fase da QCD, possam ser calculadas. A expansão da pressão em potências de µ/T é considerada para obter o segundo cumulante (c2) que é uma quantidade relacionada com a susceptibilidade do número de quarks. Primeiramente discutimos como as correções radiativas de Nc finito geradas pela OPT produzem uma contribuição que se comporta como um termo vetorial repulsivo mesmo quando este tipo de canal está ausente no potencial clássico original. Em seguida, nossos resultados são comparados com aqueles fornecidos pelas simulações na rede e também pela aproximação de Nc grande(LN). Fisicamente, os resultados da OPT são similares aqueles fornecidos pela aproximação LN quando um canal vetorial repulsivo é explicitamente incluido no potencial clássico. Neste caso, nenhuma destas aproximações analíticas produz corretamente o limite de Stefan Boltzmann para altas temperaturas. Contudo, nossos resultados sugerem como estes problemas podem ser contornados tomando-se as constantes de acoplamento como sendo dependentes da temperatura, de maneira que o fenômeno da liberdade assimptótica possa ser simulado. Esta é a primeira vez que a OPT é aplicada ao modelo de PNJL e por isto vários aspectos técnicos relacionados com o cálculo de diagramas de dois laços são também aqui apresentados.

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Livros sobre o assunto "Level repulsion"

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Fyodorov, Yan, e Dmitry Savin. Condensed matter physics. Editado por Gernot Akemann, Jinho Baik e Philippe Di Francesco. Oxford University Press, 2018. http://dx.doi.org/10.1093/oxfordhb/9780198744191.013.35.

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This article discusses some applications of concepts from random matrix theory (RMT) to condensed matter physics, with emphasis on phenomena, predicted or explained by RMT, that have actually been observed in experiments on quantum wires and quantum dots. These observations range from universal conductance fluctuations (UCF) to weak localization, non-Gaussian thermopower distributions, and sub-Poissonian shot noise. The article first considers the UCF phenomenon, nonlogarithmic eigenvalue repulsion, and sub-Poissonian shot noise in quantum wires before analysing level and wave function statistics, scattering matrix ensembles, conductance distribution, and thermopower distribution in quantum dots. It also examines the effects (not yet observed) of superconductors on the statistics of the Hamiltonian and scattering matrix.

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Bołtuć, Piotr. Church-Turing Lovers. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190652951.003.0014.

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Church-Turing Lovers are sex robots that attain every functionality of a human lover, at the desired level of granularity. Yet they have no first-person consciousness—there is “nobody home.” When such a lover says, “I love you,” there are all the intentions to please you, even computer emotions. Would you care whether your significant other is a Church-Turing Lover? Does one care about one’s lover only insofar as his/her functionalities are involved, or does one care how the lover feels. Church-Turing Lovers demonstrate how even epiphenomenal experience provides reasons to care about other people’s first-person consciousness. In a related argument, I propose the notion of the Uncanny Valley of Perfection. I systematize the standards for humanoid robots as follows: minimally humanoid (teddy bears); bottom of the Uncanny Valley (repulsive sex dolls); Silver Standard (almost human-looking), Gold Standard (hard to distinguish from humans at the right level of granularity); Platinum Standard (slightly improved on humans); the Uncanny Valley of Perfection (too much better than humans); the Slope of the Angels (no longer humanoid, viewed with awe).

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Capítulos de livros sobre o assunto "Level repulsion"

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Haake, Fritz, Sven Gnutzmann e Marek Kuś. "Level Repulsion". In Quantum Signatures of Chaos, 71–84. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-97580-1_3.

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Haake, Fritz. "Level Repulsion". In Quantum Signatures of Chaos, 37–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2001. http://dx.doi.org/10.1007/978-3-662-04506-0_3.

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Haake, Fritz. "Level Repulsion". In Quantum Signatures of Chaos, 47–59. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-05428-0_3.

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Heiss, W. D., e W. H. Steeb. "Level Repulsion and Exceptional Points". In Stochasticity and Quantum Chaos, 91–98. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-011-0169-1_8.

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Mate, C. Mathew, e Robert W. Carpick. "Physical Origins of Surface Forces". In Tribology on the Small Scale, 181–233. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780199609802.003.0007.

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The energies and forces between contacting surfaces originate from the interaction forces between atoms and molecules. This chapter discusses how these atomic level forces lead to various types of force–separation relations as two surfaces are brought into contact. This chapter covers the interactions between atoms (repulsive atomic potentials and van der Waals interactions), the interactions within liquid and aqueous media (solvation forces, electrostatic double layer, hydration repulsion, hydrophobic attraction), and electrostatic interactions from contact electrification. Due to their ubiquitous effect on adhesion, van der Waals interactions are discussed at length, including examples for calculating adhesive forces in different geometries using Hamaker constants.

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Harder, Michael, e Can-Ming Hu. "Cavity Spintronics: An Early Review of Recent Progress in the Study of Magnon–Photon Level Repulsion". In Solid State Physics, 47–121. Elsevier, 2018. http://dx.doi.org/10.1016/bs.ssp.2018.08.001.

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Campos, Esmeralda, e Genaro Zavala. "A Look into Students' Interpretation of Electric Field Lines". In Advances in Educational Technologies and Instructional Design, 342–64. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-2026-9.ch017.

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On Electricity & Magnetism (EM) courses at undergraduate level, the concept of electric field poses one of the most relevant and basic topics, along with the concept of magnetic field. Professors and students may use different diagrams as a tool to visualize the electric field, such as vectors or electric field lines. The present study aims to identify how students interpret and use electric field lines as a tool or resource to describe the electric field. Two versions of a test with open-ended questions were administered in Spanish in a private Mexican university to a random sample of students taking the EM course, and were analyzed with a qualitative approach. It was found that students do not interpret electric field lines diagrams correctly, which may lead to misconceptions. Many students based their answers on the concepts of superposition, force and repulsion.

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Winter, Mark J., e John E. Andrew. "p-Block elements". In Foundations of Inorganic Chemistry. Oxford University Press, 2000. http://dx.doi.org/10.1093/hesc/9780198792888.003.0005.

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This chapter assesses p-block elements, which are elements whose atoms have their last electron placed into a p subshell. They start with the Group 13 elements and conclude with the noble gas (Group 18) elements, at which point the final electron completes the p level. The chapter begins by explaining the trends across the periodic table: the p-block elements to the bottom left are metallic while those to the top right are non-metallic. A diagonal set of elements possess intermediate characteristics and are termed metalloids. The chapter then looks at ionic size and considers trends in the formulae of halides and oxides and in the properties of hydrides. It also studies the shapes of p-block molecules before detailing Group 13—18 elements. For p-block compounds, the Valence Shell Electron Pair Repulsion (VSEPR) method uses a simple set of electron accounting rules to carry out the prediction of the shapes of molecules.

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Shestakov, Mikhail, e Alexander Korchagin. "Computer simulation of mechanisms to reduce the metabolic costs of running while taking into account the individual characteristics of the athlete". In Technology in Sports - Recent Advances, New Perspectives and Application [Working Title]. IntechOpen, 2023. http://dx.doi.org/10.5772/intechopen.1003066.

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Previous research demonstrates the relationship between the biomechanical characteristics of running and running economics (RE). An increase in results in cycle-based sports is connected with the improvement of motion biomechanics tailored for individual athletes. The purpose of the chapter is to conduct a computer simulation of the use of biomechanical mechanisms of the lower limb muscles during running, leading to a decrease in metabolic costs. Eight biathletes took part in the experiments: all from the top 30 world ratings at the time of the study. For experiments, we used a Qualisys motion capture system, a power plate (Tredmetrix) mounted on a treadmill, a Biodex-3 complex, and a Metamax-3 gas analyzer (Cortex). OpenSim software allows modeling based on collected experimental data. This study describes the methodology of an individual approach to the process of training elite-level athletes based on computer modeling. In particular, we studied the possibility of reducing metabolic costs when working above the anaerobic limit, that is, similar to the actual competitive speed for biathlon and cross-country skiing. The results of the model experiment clearly demonstrated that one of the potential ways to reduce metabolic costs during running is the individualization of the use of biomechanical mechanisms for performing repulsion in a running step.

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Balucani, Umberto, e Marco Zoppi. "Generalized kinetic theory". In Dynamics of the Liquid State, 142–280. Oxford University PressOxford, 1995. http://dx.doi.org/10.1093/oso/9780198517399.003.0004.

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Abstract Up to the early 1970s, a ‘kinetic approach’ to the time-dependent properties of fluids was synonymous with a framework based on statistical mechanics in which a central role is played by those dynamical events referred to as uncorrelated binary collisions. Although the details of these collisional events depend on the specific form of the interatomic potential, in most cases the relevant effects are due to the harsh repulsion prevailing at small separations, often modelled as a ‘hard sphere’ interaction. As a consequence, a collision may usually be considered as an event strongly localized both in space and time. Because of this character, it seems reasonable to assume that two subsequent collisions are mutually uncorrelated. This assumption is actually one of the cornerstones of the traditional kinetic frameworks since their invention by Boltzmann more than a century ago. If we explore at a deeper qualitative level the physical content of the uncorrelated-collisions assumption, we arrive at the conclusion that this ansatz is indeed justified for dilute fluids, where the collisional events are comparatively rare so that, in a sense, a particle has available an amount of space and time sufficient to ‘forget’ a collision before the occurrence of another one.

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Trabalhos de conferências sobre o assunto "Level repulsion"

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Lehmann, Kevin K., e Stephen L. Coy. "Statistical analysis of the microwave-optical double resonance spectra of NO2: ergodicity without level repulsion?" In AIP Conference Proceedings Volume 172. AIP, 1988. http://dx.doi.org/10.1063/1.37340.

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Dong, Enyuan, Peng Tian, Yongxing Wang e Wei Liu. "The design and experimental analysis of high-speed switch in 1.14kV level based on novel repulsion actuator". In 2011 4th International Conference on Electric Utility Deregulation and Restructuring and Power Technologies (DRPT). IEEE, 2011. http://dx.doi.org/10.1109/drpt.2011.5993995.

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Penev, Kamen, e Aristides A. G. Requicha. "A Potential Field Algorithm for Fixture Synthesis in 2D". In ASME 1996 Design Engineering Technical Conferences and Computers in Engineering Conference. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-detc/cie-1343.

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Abstract A fixture is an arrangement of fixturing modules that locate and hold a workpart during a manufacturing operation. In this work we address the fixturing problem in the plane. We consider fixtures with frictionless point contacts. The focus is on contact point placement and its integration with fixture analysis. A novel method for planar fixture synthesis has been developed. It is a non-deterministic, potential field algorithm for contact point placement. The method provides a basic framework for the integration of heterogeneous high-level fixturing agents through an interface based on zones of attraction and repulsion on the workpart boundary. The algorithm may produce redundant fixtures, and can augment partial solutions to complete form closure fixtures.

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Gao, Bo, e Xiaofeng Peng. "Coupling Effect of Interfacial Transport on Particle-Surface Capillary Forces". In ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer. ASMEDC, 2008. http://dx.doi.org/10.1115/mnht2008-52033.

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In this investigation, an interest is addressed on getting some fundamental insights on the theoretical analysis of inter-particle forces and interfacial evaporation induced by the existence of liquid at pore level. The imbalance of capillary attractive forces and great potential of heat/mass transport at interfaces are found to be most important in driving the dynamic evolution of the system. Connected by micro liquid layer lying among particle(s) and supporting plate, the particle-surface system can experience both repulsion and attraction interactions. Based on the theoretical model proposed in current investigation, the particle’s mechanical status is found to be closely dependent on particle-surface distance, contact line radius, contact properties and mean curvature of the interface. Meanwhile, geometrical information and governing equations bridge interfacial transport together with possible particle movements.

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Chien, Jui-Ta, Yung-Hsing Fu, Chao-Ting Chen, Shun-Chiu Lin, Yi-Chung Shu e Wen-Jong Wu. "Broadband Rotational Energy Harvesting Using Micro Energy Harvester". In ASME 2018 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/smasis2018-8029.

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This paper proposes a broadband rotational energy harvesting setup by using micro piezoelectric energy harvester (PEH). When driven in different rotating speed, the PEH can output relatively high power which exhibits the phenomenon of frequency up-conversion transforming the low frequency of rotation into the high frequency of resonant vibration. It aims to power self-powered devices used in the applications, like smart tires, smart bearings, and health monitoring sensors on rotational machines. Through the excitation of the rotary magnetic repulsion, the cantilever beam presents periodically damped oscillation. Under the rotational excitation, the maximum output voltage and power of PEH with optimal impedance is 28.2 Vpp and 663 μW, respectively. The output performance of the same energy harvester driven in ordinary vibrational based excitation is compared with rotational oscillation under open circuit condition. The maximum output voltage under 2.5g acceleration level of vibration is 27.54 Vpp while the peak output voltage of 36.5 Vpp in rotational excitation (in 265 rpm).

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Jain, Kunal, e J. J. McCarthy. "Discrete Characterization of Cohesion in Gas-Solid Flows". In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32491.

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Cohesive forces between grains can arise from a variety of sources – such as liquid bridge (capillary) forces, van der Waals forces, or electrostatic forces – and may play a significant role in the processing of fine and/or moist powders. While recent advances have been made in our understanding of liquid-induced cohesion at the macroscopic level, in general, it is still not possible to directly connect this macroscopic understanding of cohesion with a microscopic picture of the particle properties and interaction forces. In fact, conventional theories make no attempt to distinguish between these modes of cohesion, despite clear qualitative differences (lubrication forces in wet systems or electrostatic repulsion are two good examples). In this work, we discuss several discrete characterization tools for wet (cohesive) granular material with simple, physically relevant interpretations. We examine the utility of these tools, both computationally and experimentally, by exploring a range of cohesive strengths (from cohesionless to cohesive) in several prototypical applications of solid and gas-solid flows.

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Michopoulos, John G., Athanasios Iliopoulos e Marcus Young. "Towards Static Contact Multiphysics of Rough Surfaces". In ASME 2012 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/detc2012-71055.

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This paper is describing the current status of ongoing work on developing a comprehensive modeling and simulation infrastructure capable of addressing the multiphysics behavior aspects of rough surfaces in contact. The electrical and thermal response of bodies in contact under the influence of mechanical load electric currents and thermal fluxes, is a topic of interest for many application areas. We are presenting a multiscale theory leading to derivations of expressions of electric and thermal conductivities for the case of static contact. The associated model contains both an asperity based comprehensive model as well as its continuum level coupling. The mechanical pressure and the repulsion effect from electric current through the micro-contacts as well as temperature and strain rate dependence of the plastic behavior of the asperity are accounted for as well. This formalism enables the derivation of physical properties from surface topography and bulk material properties for the interface between two rough surfaces in contact. Numerical analysis results present the dependence of the derived properties from the surface characteristics applied external load and the electric current.

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Fresco, Anthony N. "Solute Ion Linear Alignment as the Energy Source to Address Aquifer Depletion Fresh Water Scarcity and Sea Level Rise". In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-65930.

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There are reports in the literature that the lives of 4 billion people are at risk either now or in the foreseeable future, and including even 130 million US citizens, mostly in the western states of California and surroundings and in Texas and Florida as being subject to water scarcity primarily due to depletion of aquifers and ground water and losses due to evaporation. 1, 2, 3 At the same time, according to the National Oceanic and Atmospheric Administration (NOAA), there is strong evidence that global sea level is now rising at an increased rate and will continue to rise during this century.4 Climate scientists at the Potsdam Institute of Climate Impact Research published a study in the journal Natural Hazards and Earth System Sciences5 that found that the economic costs of sea level rise increase more quickly than sea levels themselves. Although fresh water is scarce, obviously the oceans are virtually an infinite source of water. Rather than trying to implement difficult fresh water usage restrictions, the best solution to the sea level rise and fresh water scarcity would be to cheaply and efficiently convert sea water to fresh water and to pump the rising sea water level inland to compensate for the underground aquifer depletion. The main problem with desalination has always been, and continues to be, the high energy consumption and operating cost. Similarly, efforts in the past to transport fresh water from northern latitudes have faced the difficulty of high energy costs for pumping water over long distances. Solute ion linear alignment propulsion was presented in ASME ES2010-903966. Solute ion linear alignment is a process in which potential energy of the electrostatic fields of like charged solute ions is converted to kinetic energy. The current paper presents factors showing that solute ion linear alignment as a power generation method by flash distillation7, and which normally releases no carbon emissions, could in fact be the only way feasible to cheaply and efficiently convert sea water to fresh water and pump the rising sea water level inland to compensate for the underground aquifer depletion. Since solute ion linear alignment is based on the principle of capacitive deionization (CDI), anomalies concerning CDI are discussed. For example, for opposite electrodes separated by 1 mm and subject to a differential voltage of 1.5 volts, the resulting charge densities on opposite electrodes of over 10 Farads/gram and material densities, e.g., carbon nanofoam, of 0.5 grams/cm2, the resulting force between the positively charged ions on one electrode and the negatively charged ions on the other electrode is calculated to be in the range of 1015 Newtons based on Coulomb’s Law. The stability of charge densities in the range of 10 Coulombs/cm3 is also discussed in view of the potential energy and resulting forces of such charge densities with consideration of possible differences in dielectric properties in solids versus liquids for like-charged conditions. An analysis of the power requirements for the CDI charge absorption and regeneration cycle is compared to the potential energy available from linear alignment to show that the linear alignment process is expected to be a net energy gain process in the same category as combustion, which involves electron transfer, nuclear fission, which is the electrostatic repulsion of the protons in the nucleus, and nuclear fusion, which is caused by attraction of the nuclear force.

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Kulkarni, Girish, e Sushil Mujumdar. "Level repulsions in high transmittance modes in one-dimensional random lattices". In International Conference on Fibre Optics and Photonics. Washington, D.C.: OSA, 2012. http://dx.doi.org/10.1364/photonics.2012.m1a.3.

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He, S., e R. Ben Mrad. "Development of a multi-level repulsive force out-of-plane micro electrostatic actuator". In IECON 2009 - 35th Annual Conference of IEEE Industrial Electronics (IECON). IEEE, 2009. http://dx.doi.org/10.1109/iecon.2009.5415321.

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