Article
Engineering, Multidisciplinary
Wangpeng He, Jie Hu, Binqiang Chen, Baolong Guo
Summary: A novel sparsity-enhanced signal denoising method is proposed to enhance feature extraction performance in mechanical fault diagnosis. The method aims at matching transient fault features, constructs an effective sparse optimization objective function, ensures overall convexity with non-convex controllable parameters, and solves the optimization problem using the proximal algorithm. Results from simulation and practical fault experiment confirm the effectiveness of the proposed method in machinery fault diagnosis.
Article
Computer Science, Hardware & Architecture
Kanatip Chitavisutthivong, Sucha Supittayapornpong, Pooria Namyar, Mingyang Zhang, Minlan Yu, Ramesh Govindan
Summary: Oblivious routing distributes traffic based on predefined routes without considering traffic demands. We show that finding optimal oblivious routing is tractable for structured topologies commonly used in data-center networks. We propose an iterative algorithm that alternates between convex optimization and linear programming to obtain an automorphism-invariant solution, which improves throughput, scales well, and applies to general structured topologies.
IEEE-ACM TRANSACTIONS ON NETWORKING
(2023)
Article
Computer Science, Software Engineering
Hassan Rafique, Mingrui Liu, Qihang Lin, Tianbao Yang
Summary: This paper investigates a class of non-convex min-max problems and proposes two proximally guided stochastic optimization methods for non-smooth and smooth instances, respectively, with analysis of time complexity.
OPTIMIZATION METHODS & SOFTWARE
(2022)
Article
Energy & Fuels
Ahmed Saad Soliman, Shuping Zhu, Li Xu, Junguo Dong, Ping Cheng
Summary: The study found that surface structures like dimples and the addition of nanoparticles can effectively reduce the melting time of PCM, while the charging time decreases with the increase in electric input power.
JOURNAL OF ENERGY STORAGE
(2021)
Article
Energy & Fuels
Yuwei Chen, Hongke Li, Qing Chen, Rui Xie, Xiaohe Wang
Summary: This article proposes an optimization method for the optimal power flow of offshore wind power systems based on the convex-concave procedure. The method relaxes the nonlinear variables, reconstructs non-convex constraints, and dynamically changes the relaxation variables' gaps to ensure effective power optimization while satisfying all constraints.
FRONTIERS IN ENERGY RESEARCH
(2022)
Article
Engineering, Electrical & Electronic
Yuwei Chen, Wenbin Yang, Qing Chen, Zhaohui Shi, Lingang Yang, Xiaohe Wang
Summary: This paper proposes a modified quadratic voltage (QV) model for solving the optimal power flow (OPF) problem in meshed networks. The modifications aim to obtain exact solutions through convex relaxations and the convex-concave procedure. The iterative algorithm is proven to be convergent and applicable through mathematical analysis. Experimental results demonstrate the practicality of the proposed model and algorithm.
INTERNATIONAL JOURNAL OF ELECTRICAL POWER & ENERGY SYSTEMS
(2022)
Article
Automation & Control Systems
Jiayi Kang, Andrew Salmon, Stephen S. -T. Yau
Summary: Nonlinear filtering plays a fundamental role in many engineering problems, where the state of a system needs to be estimated based on complex dynamics and noisy measurements. This paper introduces a maximum a posteriori (MAP) framework for the Yau-Yau method and proposes convex filtering as an intermediate between linear and nonlinear filtering. By analyzing the conditions for preserving convexity in quasi-linear parabolic PDEs, the paper establishes a connection between the MAP estimator and the structure of the posterior distribution. Lastly, a novel iterative numerical method is proposed and applied to a tracking problem.
SIAM JOURNAL ON CONTROL AND OPTIMIZATION
(2023)
Article
Computer Science, Information Systems
A. M. Benaya, Mahmoud H. H. Ismail, Ahmed S. S. Ibrahim, A. Abdelaziz Salem
Summary: This paper proposes a method for secure communication in an Internet of Things (IoT) communication system by using intelligent omni-surfaces (IOS) and unmanned aerial vehicles (UAVs). The UAVs act as friendly jammers and a source of energy to power up the IoT devices. Through simulation, it is found that the proposed scheme outperforms the traditional system by 140% in terms of secrecy capacity.
Article
Automation & Control Systems
A. D. A. M. WAWRZENCZYK, J. A. N. MIELNICZUK
Summary: This paper reconsiders recent advances in parametric modeling of positive unlabeled (PU) learning and proposes an approach based on logistic fit and unknown label frequency, which can significantly improve posterior probability and label frequency estimation.
INTERNATIONAL JOURNAL OF APPLIED MATHEMATICS AND COMPUTER SCIENCE
(2022)
Article
Engineering, Environmental
Shuwei Sun, Jiabing Hu, An Deng, Xianfu Xu, Hui Ding
Summary: This study investigated the deformation and failure process of slopes with curved surfaces through model tests and numerical simulation. The results showed that the shape and curvature of the slope significantly influenced its failure behavior, and the deformation and failure process could be divided into three phases. Strain analysis and numerical modeling provided methods for engineering evaluation and landslide risk prediction of slopes with different shapes and curvatures.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2023)
Article
Nanoscience & Nanotechnology
Seungmuk Ji, Young-Shik Yun, Jihye Lee, Deok-Jin Jeon, Namsu Kim, Hyuneui Lim, Jong-Souk Yeo
Summary: This study conducts a systematic analysis of the antireflective effect of periodic nanostructures at high incident angles, and finds that nanocones exhibit a superior broadband AR effect compared to inverted nanocones for wide-angle applications.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Materials Science, Coatings & Films
Pengfei Zhu, Hongzhi Yan, Jibo Zhou, Youliang Zhou, Zhi Chen, Yu Zhang
Summary: Shot peening can effectively enhance the bending fatigue resistance of spiral bevel gears by improving surface integrity parameters. However, the effect mechanism on concave and convex surfaces needs further understanding, and its impact on transmission performance is still controversial.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Computer Science, Information Systems
Tianxi Ma, Yunhe Wang, Xiangtao Li
Summary: In this paper, a Convex Combination Multiple Populations Competitive Swarm Optimization algorithm (CDCSO) is proposed to solve the complex search optimization problem of UAVs searching for a moving target. The algorithm combines multiple populations and a novel convex combination update strategy to prevent falling into local optima and improves performance.
INFORMATION SCIENCES
(2023)
Article
Computer Science, Interdisciplinary Applications
Song Bai, Zhan Kang
Summary: The paper presents a robust topology optimization method for structures with bounded loads and spatially correlated material uncertainties. The method combines random structural loads with bounded nature and random field discretization to model uncertainties, with a focus on minimizing mean value and standard deviation of structural compliance. Numerical examples show that the proposed method results in structurally robust designs against uncertainties.
COMPUTERS & STRUCTURES
(2021)
Article
Mathematics, Applied
P. K. Mishra, K. Silva, V. M. Tripathi
Summary: In this work, the problem of a partial differential equation is studied, with the objective of exploring optimal control on lambda to establish the existence and multiplicity of solutions.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2023)
Article
Physics, Multidisciplinary
Anna Roslawska, Tomas Neuman, Benjamin Doppagne, Andrei G. Borisov, Michelangelo Romeo, Fabrice Scheurer, Javier Aizpurua, Guillaume Schull
Summary: Experimental and theoretical investigation of the interactions between excited states of a single chromophore and static and dynamic electric fields varying at the atomic scale. The fluorescence maps of the chromophore with intramolecular resolution reveal the static charge redistribution and dynamic charge oscillation associated with the molecular exciton.
Review
Chemistry, Multidisciplinary
Clarice D. Aiello, John M. Abendroth, Muneer Abbas, Andrei Afanasev, Shivang Agarwal, Amartya S. Banerjee, David N. Beratan, Jason N. Belling, Bertrand Berche, Antia Botana, Justin R. Caram, Giuseppe Luca Celardo, Gianaurelio Cuniberti, Aitzol Garcia-Etxarri, Arezoo Dianat, Ismael Diez-Perez, Yuqi Guo, Rafael Gutierrez, Carmen Herrmann, Joshua Hihath, Suneet Kale, Philip Kurian, Ying-Cheng Lai, Tianhan Liu, Alexander Lopez, Ernesto Medina, Vladimiro Mujica, Ron Naaman, Mohammadreza Noormandipour, Julio L. Palma, Yossi Paltiel, William Petuskey, Joao Carlos Ribeiro-Silva, Juan Jose Saenz, Elton J. G. Santos, Maria Solyanik-Gorgone, Volker J. Sorger, Dominik M. Stemer, Jesus M. Ugalde, Ana Valdes-Curiel, Solmar Varela, David H. Waldeck, Michael R. Wasielewski, Paul S. Weiss, Helmut Zacharias, Qing Hua Wang
Summary: This review focuses on the study of chiral degrees of freedom in matter and electromagnetic fields, discussing the recent observations of the chiral-induced spin selectivity effect and the nanophotonic strategies designed to amplify chiral light-matter interactions. The CISS effect offers opportunities for spin control and the design of room-temperature quantum devices, while chiral-optical effects could have advantages in all-optical and quantum information technologies. The review presents a vision for the future roles of chiral-influenced quantum effects in enabling room-temperature quantum technologies.
Article
Optics
Antton Babaze, Eduardo Ogando, P. Elli Stamatopoulou, Christos Tserkezis, N. Asger Mortensen, Javier Aizpurua, Andrei G. Borisov, Ruben Esteban
Summary: In this study, time-dependent density functional theory (TDDFT) was used to investigate the impact of quantum-mechanical effects on the self-interaction Green's function, which governs the electromagnetic interaction between quantum emitters and plasmonic metallic nanoantennas. The results reveal that quantum effects, such as surface-enabled Landau damping and the spill out of induced charges, strongly influence the nanoantenna-emitter interaction, leading to a redshift and broadening of plasmonic resonances. These effects are not considered in classical theories that assume a local dielectric response of the metals.
Correction
Nanoscience & Nanotechnology
Antton Babaze, Ruben Esteban, Javier Aizpurua, Andrei G. Borisov
Article
Materials Science, Multidisciplinary
Sara Nilsson, Alvaro Posada-Borbon, Mario Zapata-Herrera, Alice Bastos da Silva Fanta, David Albinsson, Joachim Fritzsche, Vyacheslav M. Silkin, Javier Aizpurua, Henrik Gronbeck, Ruben Esteban, Christoph Langhammer
Summary: This study investigates the role of high-angle grain boundaries in the oxidation of Cu nanoparticles. The sensitivity of the Cu2O shell formation to grain morphology is found to be minimal. Additionally, grain boundaries act as vacancy sinks and nuclei for Kirkendall void formation.
PHYSICAL REVIEW MATERIALS
(2022)
Review
Chemistry, Multidisciplinary
Ruben Esteban, Jeremy J. Baumberg, Javier Aizpurua
Summary: Molecular vibrations are important in micro-/nanoengineering, and Raman scattering can access their information by exploiting the interaction between molecules and photons. Surface-enhanced Raman scattering (SERS) using plasmonic resonances enables the characterization of few-or even single-molecules. The molecular optomechanics framework of SERS provides new possibilities for optomechanical nanodevices.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Article
Physics, Multidisciplinary
Falko Schmidt, Agnese Callegari, Abdallah Daddi-Moussa-Ider, Battulga Munkhbat, Ruggero Verre, Timur Shegai, Mikael Kaell, Hartmut Loewen, Andrea Gambassi, Giovanni Volpe
Summary: Researchers have demonstrated the tunable repulsive critical Casimir forces, which are important for the development of micro- and nanodevices. The stiction between parts in micro- and nanodevices, caused by attractive Casimir-Lifshitz forces, has been successfully counteracted by the repulsive critical Casimir forces. This breakthrough provides active control and precise tunability in the forces acting between the constituent parts.
Article
Nanoscience & Nanotechnology
Eric Sidney Aaron Goerlitzer, Mario Zapata-Herrera, Ekaterina Ponomareva, Deborah Feller, Aitzol Garcia-Etxarri, Matthias Karg, Javier Aizpurua, Nicolas Vogel
Summary: Molecular chirality is transferred to plasmonic lattice modes, providing a effective and tunable means to control chirality. Non-close packed, periodic arrays of achiral gold nanoparticles embedded in a polymer film are used to demonstrate this chirality transfer. The surface lattice resonances become optically active in the presence of chiral molecules, showing handedness-dependent excitation. Numerical simulations and a semi-analytical model rationalize this chirality transfer.
Article
Nanoscience & Nanotechnology
Jorge Olmos-Trigo, Cristina Sanz-Fernandez, Diego R. Abujetas, Aitzol Garcia-Etxarri, Antonio Garcia-Martin
Summary: Spin-orbit interactions of light play a crucial role in various nanophotonic applications, but the study reveals that optical mirages can still appear when particles are illuminated by spinless beams. The research demonstrates that the interference between electric and magnetic dipoles, rather than the spin-orbit interactions, is responsible for the tilted position of the nanosphere.
Article
Spectroscopy
Alberto Villar, Santos Merino, Roberto A. Boto, Javier Aizpurua, Aitzol Garcia, Mikel Azkune, Joseba Zubia
Summary: The control of wine production requires extensive chemical analysis, with a focus on quantifying total and free SO2. Existing methods lack reproducibility and require sample treatment for SO2 extraction. This study proposes a new method using Surface-Enhanced Raman Spectroscopy (SERS) and Density Functional Theory (DFT) calculations to identify key molecules' vibrational modes contributing to free SO2 concentration. The combination of theoretical predictions and experimental outcomes allows for real-time monitoring, potentially enabling portable SERS detection for in-field measurements.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2023)
Article
Optics
Mindaugas Juodenas, Erik Strandberg, Alexander Grabowski, Johan Gustavsson, Hana Sipova-Jungova, Anders Larsson, Mikael Kall
Summary: Flat metaoptics components have the potential to replace classical optics elements, leading to compact biophotonics devices when integrated with on-chip light sources and detectors. However, shaping light into wide angular range wavefronts with high efficiency using metasurfaces, as required in high-contrast microscopy applications, remains a challenge.
LIGHT-SCIENCE & APPLICATIONS
(2023)
Article
Physics, Multidisciplinary
Jon Lasa-Alonso, Jorge Olmos-Trigo, Chiara Devescovi, Pilar Hernandez, Aitzol Garcia-Etxarri, Gabriel Molina-Terriza
Summary: We prove the nonexistence of passive antidual scatterers while providing a general proof in linear electromagnetic scattering theory. However, we find that scatterers satisfying the refractive index matching condition efficiently flip the helicity of the incident field without violating the law of energy conservation. Additionally, we discover that this condition is associated with the impedance matching condition in various electromagnetism contexts, especially in Fresnel's and Mie's scattering problems. Finally, we demonstrate that index-matched media induce resonant helicity mixing on propagating electromagnetic waves by linking the refractive index matching condition to the phenomenon of avoided crossing.
PHYSICAL REVIEW RESEARCH
(2023)
Review
Chemistry, Multidisciplinary
Ruben Esteban, Jeremy J. Baumberg, Javier Aizpurua
Summary: This article describes the relationship, theoretical description, and experimental implementation of molecular optomechanics in SERS. Molecular optomechanics provides a new perspective to explain the nonlinear effects and statistical characteristics in the SERS signal. Through plasmonic resonance, SERS can characterize small numbers or even single molecules. This research is of great significance for the development of novel nanoscale optomechanical devices and the realization of quantum technology.
ACCOUNTS OF CHEMICAL RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
M. A. J. Herrera, S. N. Kempkes, M. Blanco de Paz, A. Garcia-Etxarri, I Swart, C. Morais Smith, D. Bercioux
Summary: In this study, we investigate the non-trivial phase of a two-dimensional breathing kagome lattice, and find that the corner modes are not of higher-order topology. We also analyze the protection mechanism of the corner modes and identify the conditions under which they are pinned to zero energy. Additionally, using topological and symmetry markers, we identify the two breathing phases as adiabatically disconnected different obstructed atomic limits.
Article
Materials Science, Multidisciplinary
Jon Lasa-Alonso, Jorge Olmos-Trigo, Aitzol Garcia-Etxarri, Gabriel Molina-Terriza
Summary: Helicity preserving nanostructures and metasurfaces are proposed to enhance spectroscopic features of chiral molecules. However, losses in the constituent nonmagnetic materials significantly affect the construction of helicity-conserving structures. In this study, a general procedure for evaluating the normalized helicity expectation value is presented, and applied to the case of a chiral sphere. It is found that optical losses impose an upper bound to the helicity expectation value on nonmagnetic core-shells and chiral spheres.
MATERIALS ADVANCES
(2022)
