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Some free boundary problems in potential flow regime usinga based level set method
Recent advances in the field of fluid mechanics with moving fronts are linked to the use of Level Set Methods, a versatile mathematical technique to follow free boundaries which undergo topological changes. A challenging class of problems in this context are those related to the solution of a partial differential equation posed on a moving domain, in which the boundary condition for the PDE solver has to be obtained from a partial differential equation defined on the front. This is the case of potential flow models with moving boundaries. Moreover the fluid front will possibly be carrying some material substance which will diffuse in the front and be advected by the front velocity, as for example the use of surfactants to lower surface tension. We present a Level Set based methodology to embed this partial differential equations defined on the front in a complete Eulerian framework, fully avoiding the tracking of fluid particles and its known limitations. To show the advantages of this approach in the field of Fluid Mechanics we present in this work one particular application: the numerical approximation of a potential flow model to simulate the evolution and breaking of a solitary wave propagating over a slopping bottom and compare the level set based algorithm with previous front tracking models
Optimal Power Dispatch in Direct Current Networks to Reduce Energy Production Costs and CO 2 Emissions Using the Antlion Optimization Algorithm
In this study, we present a masterâslave methodology to solve the problem of optimal power dispatch in a direct current (DC) microgrid. In the master stage, the Antlion Optimization (ALO) method solves the problem of power dispatch by the Distributed Generators (DGs); in the slave stage, a numerical method based on successive approximations (SA) evaluates the load flows required by the potential solutions proposed by the ALO technique. The objective functions in this paper are the minimization of energy production costs and the reduction of CO 2 emissions produced by the diesel generators in the microgrid. To favor energy efficiency and have a lower negative impact on the environment, the DC microgrids under study here include three DGs (one diesel generator and two generators based on renewable energy sources, i.e., solar energy and wind power) and a slack bus connected to a public electrical grid. The effectiveness of the proposed ALOâSA methodology was tested in the 21- and 69-bus test systems. We used three other optimization techniques to compare methods in the master stage: particle swarm optimization, continuous genetic algorithm, and black hole optimization. Additionally, we combined SA with every method to solve the load flow problem in the slave stage. The results show that, among the methods analyzed in this study, the proposed ALOâAS methodology achieves the best performance in terms of lower energy production costs, less CO 2 emissions, and shorter computational processing times. All the simulations were performed in MATLAB. © 2021, King Fahd University of Petroleum & Minerals.Ocampo-Toro, J. A., Garzon-Rivera, O. D., Grisales-Noreña, L. F., Montoya-Giraldo, O. D., & Gil-GonzĂĄlez, W. (2021). Optimal Power Dispatch in Direct Current Networks to Reduce Energy Production Costs and CO 2 Emissions Using the Antlion Optimization Algorithm. Arabian Journal for Science and Engineering, 46(10), 9995-10006
Effects of pseudoscalar-baryon channels in the dynamically generated vector-baryon resonances
We study the interaction of vector mesons with the octet of stable baryons in
the framework of the local hidden gauge formalism using a coupled channels
unitary approach, including also the pseudoscalar-baryon channels which couple
to the same quantum numbers. We examine the scattering amplitudes and their
poles, which can be associated to known baryon resonances,
and determine the role of the pseudoscalar-baryon channels, changing the width
and eventually the mass of the resonances generated with only the basis of
vector-baryon states
Partial Wave Analysis of the Reaction to Search for the "" Bound State
Employing the Bonn-Gatchina partial wave analysis framework (PWA), we have
analyzed HADES data of the reaction . This
reaction might contain information about the kaonic cluster "" via its
decay into . Due to interference effects in our coherent description
of the data, a hypothetical (or, specifically "")
cluster signal must not necessarily show up as a pronounced feature (e.g. a
peak) in an invariant mass spectra like . Our PWA analysis includes a
variety of resonant and non-resonant intermediate states and delivers a good
description of our data (various angular distributions and two-hadron invariant
mass spectra) without a contribution of a cluster. At a
confidence level of CL=95\% such a cluster can not contribute more than
2-12\% to the total cross section with a final state, which
translates into a production cross-section between 0.7 and 4.2 ,
respectively. The range of the upper limit depends on the assumed cluster mass,
width and production process.Comment: 7 Pages, 5 Figure
Large enhancement of deuteron polarization with frequency modulated microwaves
We report a large enhancement of 1.7 in deuteron polarization up to values of
0.6 due to frequency modulation of the polarizing microwaves in a two liters
polarized target using the method of dynamic nuclear polarization. This target
was used during a deep inelastic polarized muon-deuteron scattering experiment
at CERN. Measurements of the electron paramagnetic resonance absorption spectra
show that frequency modulation gives rise to additional microwave absorption in
the spectral wings. Although these results are not understood theoretically,
they may provide a useful testing ground for the deeper understanding of
dynamic nuclear polarization.Comment: 10 pages, including the figures coming in uuencoded compressed tar
files in poltar.uu, which also brings cernart.sty and crna12.sty files neede
Hidden beauty baryon states in the local hidden gauge approach with heavy quark spin symmetry
Using a coupled-channel unitary approach, combining the heavy quark spin symmetry and the dynamics of the local hidden gauge, we investigate the meson-baryon interaction with hidden beauty and obtain several new states of N around 11 GeV. We consider the basis of states eta (b) N, I'N, BI > (b) , BI pound (b) , B (*) I > (b) , B (*) I pound (b) , B (*) I pound (b) (*) and find four basic bound states which correspond to BI pound (b) , BI pound (b) (*) , B (*) I pound (b) and B (*) I pound (b) (*) , decaying mostly into eta (b) N and I'N and with a binding energy about 50-130 MeV with respect to the thresholds of the corresponding channel. All of them have isospin I = 1/2 , and we find no bound states or resonances in I = 3/2 . The BI pound (b) state appears in J = 1/2 , the BI pound (b) (*) in J = 3/2 , the B (*) I pound (b) appears nearly degenerate in J = 1/2 , 3/2 and the B (*) I pound (b) (*) appears nearly degenerate in J = 1/2 , 3/2, 5/2. These states have a width from 2-110 MeV, with conservative estimates of uncertainties, except for the one in J = 5/2 which has zero width since it cannot decay into any of the states of the basis chosen. We make generous estimates of the uncertainties and find that within very large margins these states appear bound
Cost analysis of skeletal-related events in Spanish patients with bone metastases from solid tumours
To estimate the cost per skeletal-related event (SRE) in patients with bone metastases secondary to solid tumours in the Spanish healthcare setting.
METHODS:
Patients diagnosed with bone metastases secondary to breast, prostate or lung cancer were included in this multicentre, observational study. SREs are defined as pathologic fracture (vertebral and non-vertebral fracture), radiation to bone, spinal cord compression or surgery to bone. Health resource utilisation associated with these events (inpatient stays, outpatient, emergency room and home health visits, nursing home stays and procedures) were collected retrospectively for all SREs that occurred in the 97 days prior to enrolment and prospectively during follow-up. Unit costs were obtained from the 2010 eSalud healthcare costs database.
RESULTS:
A total of 93 Spanish patients with solid tumours were included (31 had breast cancer, 21 prostate cancer and 41 lung cancer), contributing a total of 143 SREs to this cost analysis. Inpatient stays (between 9.0 and 29.9 days of mean length of stay per inpatient stay by SRE type) and outpatient visits (between 1.7 and 6.4 mean visits per SRE type) were the most frequently reported types of health resources utilised. The mean cost per SRE was between 2,377.79 (radiation to bone) and 7,902.62 (spinal cord compression).
CONCLUSION:
SREs are associated with a significant consumption of healthcare resources that generate a substantial economic burden for the Spanish healthcare system
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in âs = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fbâ1 of protonâproton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
Search for W' bosons decaying to an electron and a neutrino with the D0 detector
This Letter describes the search for a new heavy charged gauge boson W'
decaying into an electron and a neutrino. The data were collected with the D0
detector at the Fermilab Tevatron proton-antiproton Collider at a
center-of-mass energy of 1.96 TeV, and correspond to an integrated luminosity
of about 1 inverse femtobarn. Lacking any significant excess in the data in
comparison with known processes, an upper limit is set on the production cross
section times branching fraction, and a W' boson with mass below 1.00 TeV can
be excluded at the 95% C.L., assuming standard-model-like couplings to
fermions. This result significantly improves upon previous limits, and is the
most stringent to date.Comment: submitted to Phys. Rev. Let
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