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Hybrid deep Learning-Based Adaptive Multiple Access Schemes Underwater Wireless Networks

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Intelligent Automation & Soft Computing 2023年第2期35卷 2463-2477页

作者： d.Anitha r.A.Karthika SrM Institute of Science and Technology KattankulathurChennai603203India Vels Institute of Science Technology&Advanced StudiesChennai600117India

Achieving sound communication systems in Under Water Acoustic(UWA)environment remains challenging for *** communication scheme is complex since these acoustic channels exhibit uneven characteristics such as long propagation delay and irregular doppler *** development of machine and deep learning algorithms has reduced the burden of achieving reli-able and good communication schemes in the underwater acoustic *** paper proposes a novel intelligent selection method between the different modulation schemes such as Code division Multiple Access(CdMA),Time divi-sion Multiple Access(TdMA),and Orthogonal Frequency division Multiplexing(OFdM)techniques using the hybrid combination of the convolutional neural net-works(CNN)and ensemble single feedforward layers(SFL).The convolutional neural networks are used for channel feature extraction,and boosted ensembled feedforward layers are used for modulation selection based on the CNN *** extensive experimentation is carried out and compared with other hybrid learning models and conventional *** results demonstrate that the performance of the proposed hybrid learning model has achieved nearly 98%accuracy and a 30%increase in BEr performance which outperformed the other learning models in achieving the communication schemes under dynamic underwater environments.

关键词： Code division multiple access time division multiple access convolutional neural networks feedforward layers

On the Computations of Gas-Solid Mixture Two-Phase Flow

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Advances in Applied Mathematics and Mechanics 2014年第1期6卷 49-74页

作者： d.Zeidan r.Touma department of Mathematics Al-Balqa Applied UniversityAl-SaltJordan department of Computer Science&Mathematics Lebanese American UniversityBeirutLebanon

This paper presents high-resolution computations of a two-phase gas-solid mixture using a well-defined mathematical *** HLL riemann solver is applied to solve the riemann problem for the model *** solution is then employed in the construction of upwind Godunov methods to solve the general initial-boundary value problem for the two-phase gas-solid *** representative test cases have been carried out and numerical solutions are provided in comparison with existing numerical *** demonstrate the robustness,effectiveness and capability of these methods,the model results are compared with reference *** addition to that,these results are compared with the results of other simulations carried out for the same set of test cases using other numerical methods available in the *** diverse comparisons demonstrate that both the model equations and the numerical methods are clear in mathematical and physical concepts for two-phase fluid flow problems.

关键词： Hyperbolic conservative equations two-phase flows compressible gas-solid mixture conservation laws approximate riemann solver upwind Godunov methods numerical simulation.

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： r.V.Jolos E.A.Kolganova d.r.Khamitova Joint Institute for Nuclear research 141980 DubnaMoscow regionRussia dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

PrOPErTIES, WELdABILITY ANd APPLICATIONS OF AdVANCEd WrOUGHT SUPErALLOYS FOr GAS TUrBINE ENGINES

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Acta Metallurgica Sinica(English Letters) 2005年第1期18卷 1-14页

作者： d.L. Klarstrom V.r. Ishwar M.d. rowe Haynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USAHaynes International Inc. Kokomo Indiana IN 46904-9013 USA

Alloy selection and alloy design both require consideration of an array of material attributes, including in-service properties, weldability and fabricability. Critical properties of advanced wrought superalloys for gas turbine applications include high temperature strength, thermal stability, oxidation resistance and fatigue resistance. In this paper, the properties of twelve wrought solid-solution-strengthened and six age-hardenable superalloys are compared. Weldability is an important attribute and can be a major limiting factor in the use of certain alloys. Weldability test methods are discussed and the resistance of alloys to solidification cracking and strain-age cracking is compared. The use of weldability testing in the development of modern wrought su-peralloys is discussed with several examples cited. Finally, alloy selection for gas turbine components is outlined, taking into account both alloy properties and fabricability.

关键词： wrought superalloys mechanical properties strain-age cracking of weldments selection and application of wrought superalloys

Time Varying Gravitational Constant G via Entropic Force

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Communications in Theoretical Physics 2011年第10期56卷 691-694页

作者： M.r.Setare d.Momeni department of Science Payame Noor UniversityBijarIran department of Physics Faculty of ScienceTarbiat Moallem UniversityTehran 15614Iran

If the uncertainty principle applies to the Verlinde entropic idea, it leads to a new term in the Newton＇s second law of mechanics in the Planck＇s scale. This curious velocity dependent term inspires a frictional feature of the gravity. In this short letter we address that this new term modifies the effective mass and the Newtonian constant as the time dependent quantities. Thus we must have a running on the value of the effective mass on the particle mass m near the holographic screen and the G. This result has a nigh relation with the dirac hypothesis about the large numbers hypothesis （L.N.H.）. We propose that the corrected entropie terms via Verlinde idea can be brought as a holographic evidence for the authenticity of the dirac idea.

关键词： gravitational constant general relativing

Modeling of Long-range Intra- and Inter-Species Charged Particle Collisions for PIC Simulations

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Communications in Computational Physics 2010年第5期7卷 877-903页

作者： d.d’Andrea C.-d.Munz r.Schneider Forschungszentrum Karlsruhe-in der Helmholtz-Gemeinschaft Institut fur Kern-und EnergietechnikPF 3640D-76021 KarlsruheGermany Institut fur Aerodynamik und Gasdynamik Universitat StuttgartPfaffenwaldring 21D-70550 StuttgartGermany Forschungszentrum Karlsruhe-in der Helmholtz-Gemeinschaft Institut fur Hochleistungsimpuls und MikrowellentechnikPF 3640D-76021 KarlsruheGermany

In this paper we present the modelling of elastic intra-species electron-electron and inter-species electron-ion scattering in a plasma on the basis of the FokkerPlanck collision *** into account the equivalence of this operator with a stochastic differential equation,we propose a Particle-in-Cell based approach for the numerical solution of the Fokker-Planck collision *** we will see,the introduced numerical concept allows the simulation of the collisional relaxation process in a fully self-consistent fashion.

关键词： Coulomb collisions in plasmas collisional relaxation Fokker-Planck equation stochastic differential equation particle-in-cell method

The sensitivity of snowpack sublimation estimates to instrument and measurement uncertainty perturbed in a Monte Carlo framework

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Frontiers of Earth Science 2018年第4期12卷 728-738页

作者： d.M.HULTSTrANd S.r.FASSNACHT EASC-Watershed Science Colorado State UniversityFort CollinsCO 80523-1482USA ESS-Watershed Science Colorado State UniversityFort CollinsCO 80523-1476USA Cooperative Institute for research in the Atmosphere Fort CollinsCO 80523-1375USA Geographisches Institut Abt.KartographieGIS &FemerkundungGeorg-August-Universitat Gottingen37077GottingenGermany Natural resources Ecology Laboratory Fort CollinsCO 80523-1499USA

The bulk aerodynamic flux equation is often used to estimate snowpack sublimation since it requires meteorological measurements at only one height above the snow surface. However, to date the uncertainty of these estimates and the individual input variables and input parameters uncertainty have not been quantified. We modeled sublimation for three (average snowpack in 2005, deep snowpack in 2011, and shallow snowpack in 2012) different water years (October 1 to September 30) at West Glacier Lake watershed within the Glacier Lakes Ecosystem Experiments Site in *** performed a Monte Carlo analysis to evaluate the sensitivity of modeled sublimation to uncertainties of the input variables and parameters from the bulk aerodynamic flux equation. Input variable time series were uniformly adjusted by a normally distributed random variable with a standard deviation given as follows: 1) the manufacturer's stated instrument accuracy of 0.3A degrees C for temperature (T), 0.3 m/s for wind speed (U (z)), 2% for relative humidity (rH), and 1 mb for pressure (P); 2) 0.0093 m for the aerodynamic roughness length (z (0)) based on z (0) profiles calculations from multiple heights; and 3) 0.08 m for measurement height (z). Often z is held constant; here we used a constant z compared to the ground surface, and subsequently altered z to account for the change in snow depth (d (s) ). The most important source of uncertainty was z (0), then rH. Accounting for measurement height as it changed due to snowpack accumulation/ablation was also relevant for deeper snow. Snow surface sublimation uncertainties, from this study, are in the range of 1% to 29% for individual input parameter perturbations. The mean cumulative uncertainty was 41% for the three water years with 55%, 37%, and 32% occurring for the wet, average, and low water years. The top three variables (z varying with d (s) , z (0), and rH) accounted for 74% to 84% of the cumulative sublimation uncertainty.

关键词： snow sublimation uncertainty aerodynamic methods

damage Assessment of reinforced Concrete Structures through damage Indices:A State-of-the-Art review

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Computer Modeling in Engineering & Sciences 2021年第9期128卷 849-874页

作者： d.A.Makhloof A.r.Ibrahim Xiaodan ren College of Civil Engineering Tongji UniversityShanghai200092China

due to the developments of computer science and technology in recent years,computer models and numerical simulations for large and complicated structures can be *** the vast information and results obtained from the analysis and simulations,the damage performance is of great importance since this damage might cause enormous losses for society and humanity,notably in cases of severe damage *** of the most effective tools to handle the results about the damage performance of the structure is the damage index(dI)together with the damage states,which are used to correlate the damage indices with the damage that occurred in the actual *** of damage indices proposed and developed rely on the fact that the damage causes noticeable changes in the structural and dynamic properties of the structural components or the whole ***,this study presents a comprehensive review of the damage assessment of reinforced Concrete(rC)*** presents step by step the development of the damage indices that are most widely used to estimate the performance of structural components in the structure and subsequently assess the damage degree of such these structures either based on the structural properties or dynamic properties of the ***,several damage states have been introduced to estimate the performance level of the ***,case studies,methodologies,and applications on the damage assessment of rC structures are reviewed and presented.

关键词： Structure properties-based damage indices dynamic properties-based damage indices damage states

Prediction of semiconducting behavior in minority spin of Co_2CrZ(Z=Ga,Ge,As):LSdA

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Journal of Semiconductors 2012年第12期33卷 5-10页

作者： d.P.rai r.K.Thapa department of Physics Mizoram University

Volume optimization was performed to obtain the theoretical lattice constants by using the generalized gradient approximation （GGA）. The electronic and magnetic properties of Heusler alloys CoaCrZ （Z -- Ga, Ge, As） were investigated by using local spin density approximation （LSdA）. Amongst the systems under investigation, CoECrGe and Co2CrGa give I00% spin polarization at the Fermi level （EF）. Co2CrGe and CoECrGa are the most stable half-metallic ferromagnets （HMFs）; their EF lie exactly at the gap of 0.24 eV and 0.38 eV, respectively, in the spin-down channel. Even though CoaCrAs gives a distinct and bigger gap as compared to CoECrGa and CoECrGe, its EF is not located at the middle of the gap in the spin-down channel. We have also found that the total magnetic moments increase as the Z goes from Ga to As. The calculated density of states and band structures show the HMF character for CoECrGe and Co2CrGa.

关键词： GGA half-metallicity dOS spin polarization and band structure