3,875 research outputs found
Federated Learning over Energy Harvesting Wireless Networks
In this paper, the deployment of federated learning (FL) is investigated in
an energy harvesting wireless network in which the base station (BS) employs
massive multiple-input multiple-output (MIMO) to serve a set of users powered
by independent energy harvesting sources. Since a certain number of users may
not be able to participate in FL due to the interference and energy
constraints, a joint energy management and user scheduling problem in FL over
wireless systems is formulated. This problem is formulated as an optimization
problem whose goal is to minimize the FL training loss via optimizing user
scheduling. To find how the factors such as transmit power and number of
scheduled users affect the training loss, the convergence rate of the FL
algorithm is first analyzed. Given this analytical result, the user scheduling
and energy management optimization problem can be decomposed, simplified, and
solved. Further, the system model is extended by considering multiple BSs.
Hence, a joint user association and scheduling problem in FL over wireless
systems is studied. The optimal user association problem is solved using the
branch-and-bound technique. Simulation results show that the proposed user
scheduling and user association algorithm can reduce training loss compared to
a standard FL algorithm.Comment: To appear in IEEE Internet of Things Journa
Parameters identification and optimization of photovoltaic panels under real conditions using Lambert W-function
This paper proposes a new approach based on Lambert W-function to extract the electrical parameters of photovoltaic (PV) panels. This approach can extract the optimal electrical characteristics of the PV panel under variable conditions of irradiation and temperature. Three benchmarking panels (shell SP70 monocrystalline silicon, shell ST40 thin film, and KC200GT Polycrystalline Silicon) are demonstrated and analyzed considering the electrical characteristics provided by the manufacturers. A comprehensive assessment is carried out under different weather condition to validate the capability and the robustness of the proposed approach. Furthermore, the simulated output characteristics of the three modules Photovoltaic are almost comparable and reproduce faithfully the manufacturer’s experimental data The novelty of this study is the using a new hybrid analytical and numerical method that straight forward and effective given value of Root mean square error less than those obtained by others methods that indicate the estimated results are very close to the experimental values provided by the manufacturers
Lepton Polarization Asymmetry in B l l(bar) decays in R-parity violating Minimal Supersymmetric Standard Model
We study the implication of R-parity violating Rp Minimal Supersymmetric
Standard Model (MSSM) model in lepton polarization asymmetry ALP in B l l(bar)
decays . The analysis show that the ALP is significant in a certain
phenomenological parametric region of Yukawa couplings. We have also placed
indirect bounds on Lambda' lambda couplings as obtained from B t t(bar).Comment: 6 pages, 4 figures Changes of notation in Eq(8-11,17-19),Eq.20 adde
Blue light effects on rose photosynthesis and photomorphogenesis
Through its impact on photosynthesis and morphogenesis, light is the environmental factor that most affects plant architecture. Using light rather than chemicals to manage plant architecture could reduce the impact on the environment. However, the understanding of how light modulates plant architecture is still poor and further research is needed. To address this question, we examined the development of two rose cultivars, Rosa hybrida‘Radrazz’ and Rosa chinensis‘Old Blush’, cultivated under two light qualities. Plants were grown from one-node cuttings for 6 weeks under white or blue light at equal photosynthetic efficiencies. While plant development was totally inhibited in darkness, blue light could sustain full development from bud burst until flowering. Blue light reduced the net CO2 assimilation rate of fully expanded leaves in both cultivars, despite increasing stomatal conductance and intercellular CO2 concentrations. In ‘Radrazz’, the reduction in CO2 assimilation under blue light was related to a decrease in photosynthetic pigment content, while in both cultivars, the chl a/b ratio increased. Surprisingly, blue light could induce the same organogenetic activity of the shoot apical meristem, growth of the metamers and flower development as white light. The normal development of rose plants under blue light reveals the strong adaptive properties of rose plants to their light environment. It also indicates that photomorphogenetic processes can all be triggered by blue wavelengths and that despite a lower assimilation rate, blue light can provide sufficient energy via photosynthesis to sustain normal growth and development in roses
Multiloop control strategy for grid-interfaced three-phase voltage source inverter with passively damped LLCL-filter
In inverter-based distributed generation (IBDG) and similar to the conventional third order LCL filter, the high order LLCL filter is difficult to stabilize, and may cause a resonance between the inverter and the grid. Passive damping techniques were explored in literature by connecting a resistor in different locations of the LLCL filter. This paper presents the performance of the high-order LLCL-filter with RC passive damping circuit through evaluating the system stability using dual-loop control strategy that has been applied to the LCL-filter. Comparative analysis regarding PI and PR controllers used in the proposed control strategy is offered. Simulation results using Matlab are conducted, presented, and discussed.Qatar National Research FundScopu
Fermionic coherent states for pseudo-Hermitian two-level systems
We introduce creation and annihilation operators of pseudo-Hermitian fermions
for two-level systems described by pseudo-Hermitian Hamiltonian with real
eigenvalues. This allows the generalization of the fermionic coherent states
approach to such systems. Pseudo-fermionic coherent states are constructed as
eigenstates of two pseudo-fermion annihilation operators. These coherent states
form a bi-normal and bi-overcomplete system, and their evolution governed by
the pseudo-Hermitian Hamiltonian is temporally stable. In terms of the
introduced pseudo-fermion operators the two-level system' Hamiltonian takes a
factorized form similar to that of a harmonic oscillator.Comment: 13 pages (Latex, article class), no figures; v2: some amendments in
section 2, seven new refs adde
Comparative Study of Human and Automated Screening for Antinuclear Antibodies by Immunofluorescence on HEp-2 Cells
Background: Several automated systems had been developed in order to reduce inter-observer variability in
indirect immunofluorescence (IIF) interpretation. We aimed to evaluate the performance of a processing system in
antinuclear antibodies (ANA) screening on HEp-2 cells.
Patients and Methods: This study included 64 ANA-positive sera and 107 ANA-negative sera that underwent IIF on two
commercial kits of HEp-2 cells (BioSystems® and Euroimmun®). IIF results were compared with a novel automated
interpretation system, the “CyclopusCADImmuno®” (CAD).
Results: All ANA-positive sera images were recognized as positive by CAD (sensitivity = 100%), while 17 (15.9%) of the
ANA-negative sera images were interpreted as positive (specificity = 84.1%), =0.799 (SD=0.045). Comparison of IIF
pattern determination between human and CAD system revealed on HEp-2 (BioSystems®), a complete concordance in
6 (9.37%) sera, a partial concordance (sharing of at least 1 pattern) in 42 (65.6%) cases and in 16 (25%) sera the
pattern interpretation was discordant. Similarly, on HEp-2 (Euroimmun®) the concordance in pattern interpretation was
total in 5 (7.8%) sera, partial in 39 (60.9%) and absent in 20 (31.25%). For both tested HEp-2 cells kits agreement was
enhanced for the most common patterns, homogenous, fine speckled and coarse speckled. While there was an issue in
identification of nucleolar, dots and nuclear membranous patterns by CAD.
Conclusion: Assessment of ANA by IIF on HEp-2 cells using the automated interpretation system, the
“CyclopusCADImmuno®” is a reliable method for positive/negative differentiation. Continuous integration of IIF images
would improve the pattern identification by the CAD
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