188 research outputs found

    Designing smart pulse flow meters using diversion analysis

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    The operation of modern housing infrastructure is characterized by a constant increase in the cost of the limited resources used. This necessitates the priority implementation in the concept of a smart home of elements aimed at resource saving and their rational management. The study provides an overview of the implementation architectures of the internet of things (IoT) concept in the construction of home automation systems and the requirements they impose on the implementation of smart primary meters of controlled physical quantities. Based on a diversion analysis, a promising smart water meter was developed. The prototype is ergonomic and has a structural form factor convenient for further integration. The designed model of the electronic module of the water flow monitoring system implements, in addition to typical tasks, additional functionality: transfer of recorded indicators and technical information to the cloud storage, warning the user about an emergency situation, accumulation of current data in non-volatile memory. It is possible to use the accumulated statistics for training the predictive analysis module. The proposed architecture option will allow creating energy-efficient elements of home automation systems in the future

    Extreme plasma states in laser-governed vacuum breakdown

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    Triggering vacuum breakdown at the upcoming laser facilities can provide rapid electron-positron pair production for studies in laboratory astrophysics and fundamental physics. However, the density of the emerging plasma should seemingly stop rising at the relativistic critical density, when the plasma becomes opaque. Here we identify the opportunity of breaking this limit using optimal beam configuration of petawatt-class lasers. Tightly focused laser fields allow plasma generation in a small focal volume much less than λ3{\lambda}^3, and creating extreme plasma states in terms of density and produced currents. These states can be regarded as a new object of nonlinear plasma physics. Using 3D QED-PIC simulations we demonstrate the possibility of reaching densities of more than 102510^{25} cm−3^{-3}, which is an order of magnitude higher than previously expected. Controlling the process via the initial target parameters gives the opportunity to reach the discovered plasma states at the upcoming laser facilities

    RESULTS OF CANALOPLASTY IN GLAUCOMA SURGERY. REVIEW OF LITERATURE

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    The article presents a review of literature on a micro-invasive surgical treatment of glaucoma based on the principle of recovery of natural pathways of aqueous humor outflow through the Schlemm’s canal. The surgical experience of this operation revealed a number of advantages versus the trabeculectomy, including, a more physiologic approach, a less quantity of intraand postoperative complications, a rapid rehabilitation of the patients

    Overtones of Isoscalar Giant Resonances in medium-heavy and heavy nuclei

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    A semi-microscopic approach based on both the continum-random-phase-approximation (CRPA) method and a phenomenological treatment of the spreading effect is extended and applied to describe the main properties (particle-hole strength distribution, energy-dependent transition density, partial direct-nucleon-decay branching ratios) of the isoscalar giant dipole, second monopole, and second quadrupole resonances. Abilities of the approach are checked by description of gross properties of the main-tone resonances. Calculation results obtained for the resonances in a few singly- and doubly-closed-shell nuclei are compared with available experimental data.Comment: 12 pages, 14 figures, submitted to Phys. Rev.

    Isoscalar Giant Dipole Resonance and Nuclear Matter Incompressibility Coefficient

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    We present results of microscopic calculations of the strength function, S(E), and alpha-particle excitation cross sections sigma(E) for the isoscalar giant dipole resonance (ISGDR). An accurate and a general method to eliminate the contributions of spurious state mixing is presented and used in the calculations. Our results provide a resolution to the long standing problem that the nuclear matter incompressibility coefficient, K, deduced from sigma(E) data for the ISGDR is significantly smaller than that deduced from data for the isoscalar giant monopole resonance (ISGMR).Comment: 4 pages using revtex 3.0, 3 postscript figures created by Mathematica 4.

    Ultrabright GeV photon source via controlled electromagnetic cascades in laser-dipole waves

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    One aim of upcoming high-intensity laser facilities is to provide new high-flux gamma-ray sources. Electromagnetic cascades may serve for this, but are known to limit both field strengths and particle energies, restricting efficient production of photons to sub-GeV energies. Here we show how to create a directed GeV photon source, enabled by a controlled interplay between the cascade and anomalous radiative trapping. Using advanced 3D QED particle-in-cell (PIC) simulations and analytic estimates, we show that the concept is feasible for planned peak powers of 10 PW level. A higher peak power of 40 PW can provide 10910^9 photons with GeV energies in a well-collimated 3 fs beam, achieving peak brilliance 9×1024{9 \times 10^{24}} ph s−1^{-1}mrad−2^{-2}mm−2^{-2}/0.1%{\%}BW. Such a source would be a powerful tool for studying fundamental electromagnetic and nuclear processes

    Semimicroscopical description of the simplest photonuclear reactions accompanied by excitation of the giant dipole resonance in medium-heavy mass nuclei

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    A semimicroscopical approach is applied to describe photoabsorption and partial photonucleon reactions accompanied by the excitation of the giant dipole resonance (GDR). The approach is based on the continuum-RPA (CRPA) with a phenomenological description for the spreading effect. The phenomenological isoscalar part of the nuclear mean field, momentum-independent Landau-Migdal particle-hole interaction, and separable momentum-dependent forces are used as input quantities for the CRPA calculations. The experimental photoabsorption and partial (n,γ)(n,\gamma)-reaction cross sections in the vicinity of the GDR are satisfactorily described for 89^{89}Y, 140^{140}Ce and 208^{208}Pb target nuclei. The total direct-neutron-decay branching ratio for the GDR in 48^{48}Ca and 208^{208}Pb is also evaluated.Comment: 19 pages, 5 eps figure
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