المؤلفون: Tatsuaki Kimura

المصدر: IEEE Transactions on Mobile Computing. 22:2205-2220

مصطلحات موضوعية: symbols.namesake, Computer Networks and Communications, Computer science, symbols, Statistical physics, Electrical and Electronic Engineering, Interference (wave propagation), Poisson distribution, Software

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::6764e15cc2a885b1240e43bbe21440d0Test
https://doi.org/10.1109/tmc.2021.3116314Test

المؤلفون: Mónica Benito, Michael Niklas, Sigmund Kohler

المصدر: Digital.CSIC. Repositorio Institucional del CSIC
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مصطلحات موضوعية: Physics, 73.23.Hk, Trace (linear algebra), Condensed Matter - Mesoscale and Nanoscale Physics, 42.50.Lc, Computation, ddc:530, FOS: Physical sciences, Markov process, 530 Physik, Interference (wave propagation), 01 natural sciences, 010305 fluids & plasmas, symbols.namesake, Operator (computer programming), 05.60.Gg, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Master equation, Statistics, symbols, 010306 general physics, Adiabatic process, Numerical stability

الوصف: We develop a scheme for the computation of the full-counting statistics of transport described by Markovian master equations with an arbitrary time dependence. It is based on a hierarchy of generalized density operators, where the trace of each operator yields one cumulant. This direct relation offers a better numerical efficiency than the equivalent number-resolved master equation. The proposed method is particularly useful for conductors with an elaborate time-dependence stemming, e.g., from pulses or combinations of slow and fast parameter switching. As a test bench for the evaluation of the numerical stability, we consider time-independent problems for which the full-counting statistics can be computed by other means. As applications, we study cumulants of higher order for two time-dependent transport problems of recent interest, namely steady-state coherent transfer by adiabatic passage and Landau-Zener-St\"uckelberg-Majorana interference in an open double quantum dot.
Comment: 7 pages, 5 figures

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7035f1fb753480e1c42e85509cf109a7Test
https://opus.bibliothek.uni-augsburg.de/opus4/frontdoor/index/index/docId/104288Test

المؤلفون: M. Asif, Mohammad Mirzazadeh, Kamyar Hosseini, Lanre Akinyemi, M. Raheel, Asim Zafar

المصدر: Journal of Ocean Engineering and Science. 7:337-344

مصطلحات موضوعية: Environmental Engineering, Current (mathematics), Wave propagation, Ocean Engineering, Conformable matrix, Type (model theory), Oceanography, Differential operator, Nonlinear system, symbols.namesake, Nonlinear Sciences::Exactly Solvable and Integrable Systems, symbols, Applied mathematics, Soliton, Nonlinear Sciences::Pattern Formation and Solitons, Schrödinger's cat, Mathematics

الوصف: The current study deals with exact soliton solutions for Schrodinger-Hirota (SH) equation via two modified integration methods. Those methods are known as the improved ( G ′ / G ) -expansion method and the Kudryashov method. This model is a generalized version of the nonlinear Schrodinger (NLS) equation with higher order dispersion and cubic nonlinearity. It can be considered as a more accurate approximation than the NLS equation in explaining wave propagation in the ocean and optical fibers. A novel derivative operator named as the conformable truncated M-fractional is used to study the above mentioned model. The obtained results can be used in describing the Schrodinger-Hirota equation in some better way. Moreover the obtained results are verified through symbolic computational software. Also, the obtained results show that the suggested approaches have broaden capacity to secure some new soliton type solutions for the fractional differential equations in an effective way. In the end, the results are also explained through their graphical representations.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::90b0d3df0ab43cf66d3fdeae49034f92Test
https://doi.org/10.1016/j.joes.2021.09.007Test

المؤلفون: Fengkui Gong, Yunfei Chen, Junlin Zhang, Mingqian Liu, Nan Zhao, Ning Zhang, Qinghai Yang

المصدر: IEEE Internet of Things Journal. 9:11324-11335

مصطلحات موضوعية: Computer Networks and Communications, Computer science, Covariance matrix, business.industry, TK, MIMO, Interference (wave propagation), Computer Science Applications, symbols.namesake, Cognitive radio, TA, Hardware and Architecture, Gaussian noise, Signal Processing, symbols, Wireless, Cluster analysis, business, Algorithm, Gaussian network model, Computer Science::Information Theory, Information Systems

الوصف: Identification of transmit-antenna number is of importance in cognitive Internet of Things with multiple-input multiple-output (MIMO). Previous studies on transmit-antenna number detection only consider Gaussian noise and ignore impulsive interference. In the practical wireless communication, impulsive interference may exist due to low-frequency atmospheric noise, multiple access and electromagnetic disturbance. Such interference can usually be modeled as symmetric alpha stable (SαS), which cause the performance degradation of conventional algorithms based on Gaussian model. In this paper, we present a novel scheme to detect the transmit-antenna number for MIMO systems in cognitive Internet of Things, assuming that signals are corrupted by both SαS interference and Gaussian noise. We first introduce a new approach to characterize the generalized correlation matrix, and provide its bound with SαS interference. Then, the discriminating feature vector is constructed by utilizing the higher-order moments (HOM) of eigenvalues of the generalized correlation matrix. Finally, an advanced clustering algorithm is employed to detect the transmit-antenna number, using the cluster where the minimum eigenvalue is located. The proposed algorithm avoids the need for a priori information about the transmitted signals, such as coding mode, modulation type and pilot patterns. Simulation experiments demonstrate the feasibility of the proposed transmit-antenna number detection scheme in MIMO systems with Gaussian noise and SαS interference.

وصف الملف: application/pdf

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::9ea1b70b42f200ed79488878da43f022Test
https://doi.org/10.1109/jiot.2021.3127747Test

المؤلفون: Wen Zhan, Tony Q. S. Quek, Xinghua Sun, Xijun Wang, Fangming Zhao, Howard H. Yang

المصدر: IEEE Internet of Things Journal. 9:6816-6829

مصطلحات موضوعية: Networking and Internet Architecture (cs.NI), FOS: Computer and information sciences, Computer Networks and Communications, Computer science, Information Theory (cs.IT), Computer Science - Information Theory, Monotonic function, Poisson distribution, Interference (wave propagation), Topology, Computer Science Applications, Computer Science - Networking and Internet Architecture, symbols.namesake, Coupling (computer programming), Transmission (telecommunications), Hardware and Architecture, Signal Processing, symbols, Limit (mathematics), Random access, Information Systems, Communication channel

الوصف: Timeliness is an emerging requirement for many Internet of Things (IoT) applications. In IoT networks, where a large-number of nodes are distributed, severe interference may incur during the transmission phase which causes age of information (AoI) degradation. It is therefore important to study the performance limit of AoI as well as how to achieve such limit. In this paper, we aim to optimize the AoI in random access Poisson networks. By taking into account the spatio-temporal interactions amongst the transmitters, an expression of the peak AoI is derived, based on explicit expressions of the optimal peak AoI and the corresponding optimal system parameters including the packet arrival rate and the channel access probability are further derived. It is shown that with a given packet arrival rate (resp. a given channel access probability), the optimal channel access probability (resp. the optimal packet arrival rate), is equal to one under a small node deployment density, and decrease monotonically as the spatial deployment density increases due to the severe interference caused by spatio-temproal coupling between transmitters. When joint tuning of the packet arrival rate and channel access probability is performed, the optimal channel access probability is always set to be one. Moreover, with the sole tuning of the channel access probability, it is found that the optimal peak AoI performance can be improved with a smaller packet arrival rate only when the node deployment density is high, which is contrast to the case of the sole tuning of the packet arrival rate, where a higher channel access probability always leads to better optimal peak AoI regardless of the node deployment density. In all the cases of optimal tuning of system parameters, the optimal peak AoI linearly grows with the node deployment density as opposed to an exponential growth with fixed system parameters.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b256658303c03baa5671d1b16417a234Test
https://doi.org/10.1109/jiot.2021.3115780Test

المؤلفون: Philippe Rostaing, Roland Gautier, Clément Demeslay

المساهمون: Equipe Security, Intelligence and Integrity of Information (Lab-STICC_SI3), Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), Institut Mines-Télécom [Paris] (IMT)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-Institut Mines-Télécom [Paris] (IMT)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-École Nationale d'Ingénieurs de Brest (ENIB)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)

المصدر: IEEE internet of things journal
IEEE internet of things journal, IEEE, 2021, pp.1-1. ⟨10.1109/JIOT.2021.3114439⟩

مصطلحات موضوعية: Signal Processing (eess.SP), Computer Networks and Communications, Computer science, Monte Carlo method, 02 engineering and technology, Interference (wave propagation), Discrete Fourier transform, LoRa interference, symbols.namesake, LoRa waveform, FOS: Electrical engineering, electronic engineering, information engineering, 0202 electrical engineering, electronic engineering, information engineering, Waveform, Fading, Electrical Engineering and Systems Science - Signal Processing, performance analysis, Computer Science::Information Theory, Detector, 020206 networking & telecommunications, Computer Science Applications, multi-path channel, Additive white Gaussian noise, Hardware and Architecture, Signal Processing, symbols, 020201 artificial intelligence & image processing, chirp modulation, [SPI.SIGNAL]Engineering Sciences [physics]/Signal and Image processing, Algorithm, Information Systems, Communication channel

الوصف: International audience; This paper presents a semi-analytical approximation of Symbol Error Rate (SER) for the well known LoRa Internet of Things (IoT) modulation scheme in the following two scenarios: 1) in multi-path frequency selective fading channel with Additive White Gaussian Noise (AW GN) and 2) in the presence of a second interfering LoRa user in flat-fading AW GN channel. Performances for both coherent and non-coherent cases are derived by considering the common Discrete Fourier transform (DF T) based detector on the received LoRa waveform. By considering these two scenarios, the detector exhibits parasitic peaks that severely degrade the performance of the LoRa receiver. We propose in that sense a theoretical expression for this result, from which a unified framework based on peak detection probabilities allows us to derive SER, which is validated by Monte Carlo simulations. Fast computation of the derived closedform SER allows to carry out deep performance analysis for these two scenarios.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::c933183c9d9ec9cae43ee2085be39fb4Test
https://doi.org/10.1109/jiot.2021.3114439Test

المؤلفون: Jean-Louis Izbicki, Bruno Morvan, P. Pareige, Damien Leduc

مصطلحات موضوعية: Materials science, Wave propagation, business.industry, Mechanical Engineering, Acoustics, Attenuation, Classical Physics (physics.class-ph), FOS: Physical sciences, Surface finish, Physics - Classical Physics, Condensed Matter Physics, symbols.namesake, Optics, Lamb waves, Surface metrology, Surface wave, symbols, General Materials Science, Phase velocity, Rayleigh wave, business, Physics::Atmospheric and Oceanic Physics

الوصف: This work deals with the sensitivity to the plate roughness of Lamb waves. An experimental study is performed involving an air-coupling transducer system. Signal processing allows us to extract the Lamb waves characteristics: phase velocity and attenuation. Plate surface topographies are obtained by means of an optical surface profiler. The acoustic characteristics and the surface topographies are finally linked.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a3708648ab3dc8c4ec1d90b5013ea656Test
http://arxiv.org/abs/2304.10393Test

المؤلفون: Ling Yu, Zhengyou He, Ruikun Mai, Xiaopeng Li, Siyu Xiong, Ling Fu

المصدر: IEEE Transactions on Power Delivery. 37:1193-1202

مصطلحات موضوعية: Computer science, Phasor, Energy Engineering and Power Technology, Fundamental frequency, Frequency deviation, Interference (wave propagation), Discrete Fourier transform, Power (physics), Electric power system, symbols.namesake, Taylor series, symbols, Electrical and Electronic Engineering, Algorithm

الوصف: The existence of out-of-band interference (OBI) signals in power systems will dramatically degrade the performance of synchrophasor estimation. In order to alleviate the influence of OBI, a hybrid phasor model is proposed, in which the OBI phasor and the dynamic fundamental phasor are expressed by Taylor series, respectively. Then, the rough fundamental frequency and OBI frequency estimation are achieved via the rough fundamental component and OBI component estimated from discrete Fourier transform (DFT). For attaining the accurate phasor, the proposed algorithm can invoke the corresponding coefficient matrices calculated off-line according to whether the power signal contains OBI or not. Finally, field data and computer-generated signals are used to assess the proposed algorithm performance. The results obtained indicate that the proposed algorithm can enhance phasor estimation performance by keeping maximum TVEs below 0.001% and 1% under frequency deviation and power modulation tests with OBI, respectively.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::20131257826e1d8e28e731cabb06db06Test
https://doi.org/10.1109/tpwrd.2021.3079990Test

المؤلفون: Shantanu S. Mulay, Soniya Chaudhary

المصدر: Applied Mathematical Modelling. 103:493-515

مصطلحات موضوعية: Shearing (physics), Materials science, Wave propagation, Applied Mathematics, Multiphysics, Mechanics, Piezoelectricity, symbols.namesake, Maxwell's equations, Surface wave, Modeling and Simulation, symbols, Boundary value problem, Electric displacement field

الوصف: This paper presents a mathematical modelling of a novel multiphysics (electro-mechanic coupling) problem of the shear wave propagation in laminated structures (piezoelectric - hydrogel - elastic substrate) using the wave mode method while finding the general solution for each medium. A dynamic mechanical equilibrium equation (for transverse deflection) and Maxwell equation (for electric potential) are solved in a coupled manner over each domain resulting a general closed-form solution. A specific analytical solution is then obtained enforcing the boundary conditions at the top of piezoelectric layer and the interface continuity requirements between each layer and the elastic half-space. A novel approach, to uncouple the coupled equations, is presented resulting in a final systematic solution. The effect of x coordinate (thickness) on the field variables is carefully examined for the electrically open and short cases. The jump in the stress and electric displacement components (causing delamination due to shearing mode of fracture) is present across all the interfaces due to the different bulk material constants. The key contribution of the current work is demonstrating the influence of fixed-charge concentration inside the hydrogel layer on the shear wave propagation. The present study thus provides a new concept for adjusting and controlling the elastic wave propagation in the composite structures, and provides a proper theoretical understanding of wave propagation in the damage tolerance-based design of piezotronics devices.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::f53c38d74f048bf295d0c76d1b44d4b4Test
https://doi.org/10.1016/j.apm.2021.10.035Test

المؤلفون: Qiwei Zhan, Wen-Yan Yin, Yuan Fang, Qiang Ren, Qing Huo Liu, Yiyao Wang, Shiyou Yang

المصدر: IEEE Transactions on Antennas and Propagation. 70:2082-2092

مصطلحات موضوعية: Physics, symbols.namesake, Maxwell's equations, Field (physics), Wave propagation, Discontinuous Galerkin method, symbols, Plane wave, Basis function, Electrical and Electronic Engineering, Solver, Algorithm, Riemann solver

الوصف: This paper presents a stabilized nodal discontinuous Galerkin pseudospectral time domain (DG-PSTD) algorithm for fully anisotropic electromagnetic waves. This solver permits arbitrary high-order basis functions and adaptive hexahedral elements, thus very efficient for large-scale wave propagation in complex media. Maxwell’s equations are reformulated in a unified hyperbolic form, where a localized anisotropic Riemann solver is derived to serve as a numerical flux to exchange information across adjacent elements in the DG-PSTD scheme. This local analysis method also helps impose the time-domain anisotropic plane wave incidence in the total/scattering field framework. Numerical validations and applications demonstrate the efficiency, accuracy, and capability of this new high-order solver for 3-D large-scale generally anisotropic electromagnetic media.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::c12e33c18337dd1c3f83f904f1936e86Test
https://doi.org/10.1109/tap.2021.3111639Test