400 research outputs found
Meter of Initial Speed of Mobile Object
The need to measure the initial velocity of a moving object is shown. A brief review and analysis of existing technical means suitable for solving the problem is given. The constructions of devices and their elements for measuring the initial velocity of a mobile object, structural diagrams of devices for measuring the initial velocity of a mobile object are considered. A design with a capacitive converter is proposed, which forms an information impulse. The results of the development can be used to design and manufacture the device
Randomness in Classical Mechanics and Quantum Mechanics
The Copenhagen interpretation of quantum mechanics assumes the existence of
the classical deterministic Newtonian world. We argue that in fact the Newton
determinism in classical world does not hold and in classical mechanics there
is fundamental and irreducible randomness. The classical Newtonian trajectory
does not have a direct physical meaning since arbitrary real numbers are not
observable. There are classical uncertainty relations, i.e. the uncertainty
(errors of observation) in the determination of coordinate and momentum is
always positive (non zero).
A "functional" formulation of classical mechanics was suggested. The
fundamental equation of the microscopic dynamics in the functional approach is
not the Newton equation but the Liouville equation for the distribution
function of the single particle. Solutions of the Liouville equation have the
property of delocalization which accounts for irreversibility. The Newton
equation in this approach appears as an approximate equation describing the
dynamics of the average values of the position and momenta for not too long
time intervals. Corrections to the Newton trajectories are computed. An
interpretation of quantum mechanics is attempted in which both classical and
quantum mechanics contain fundamental randomness. Instead of an ensemble of
events one introduces an ensemble of observers.Comment: 12 pages, Late
The nonabelian Liouville-Arnold integrability by quadratures problem: a symplectic approach
A symplectic theory approach is devised for solving the problem of
algebraic-analytical construction of integral submanifold imbeddings for
integrable (via the nonabelian Liouville-Arnold theorem) Hamiltonian systems on
canonically symplectic phase spaces
Antimicrobial drug consumption in the Russian Federation (2008–2022): pharmacoepidemiological study
Objective.
To assess the dynamics of antimicrobial drug consumption in the Russian Federation.
Materials and Methods.
Data on antimicrobials for systemic use (ATC class J01) sales for the period 2008–2022 in the hospital and outpatient segment were downloaded from the IQVIA database. The absolute quantities of purchased antimicrobials were transferred to the defined daily doses (DDD) separately for the outpatient and hospital segments for each year of observation.
Results.
Over the period 2008-2022 there was an increase in antimicrobials consumption from 9.7 to 14.2 DDDs per 1000 inhabitants/day with a transient rise of up to 18.7 DDDs per 1000 inhabitants/day in 2020. In the outpatient segment, antimicrobials consumption was increased from 9.7 to 12.04 DDDs per 1000 population/day (a transient rise to 15.6 DDDs in 2020), and in the inpatient segment from 266.3 to 412.2 DDDs per 100 bed-days, respectively. When analyzing antimicrobials by access group (WHO classification AWaRe), there was a decrease in consumption «Access» group antimicrobials from 62% to 45%, an increase of «Watch» group antimicrobials from 38% to 63.4% and «Reserve» antimicrobials from 0.005% to 1.6%.
Conclusions.
The increase in consumption of «Watch» group antimicrobials requires effective use control measures to be implemented at both outpatient and inpatient medical care settings at the national level
The type numbers of closed geodesics
A short survey on the type numbers of closed geodesics, on applications of
the Morse theory to proving the existence of closed geodesics and on the recent
progress in applying variational methods to the periodic problem for Finsler
and magnetic geodesicsComment: 29 pages, an appendix to the Russian translation of "The calculus of
variations in the large" by M. Mors
Bouncing and Accelerating Solutions in Nonlocal Stringy Models
A general class of cosmological models driven by a non-local scalar field
inspired by string field theories is studied. In particular cases the scalar
field is a string dilaton or a string tachyon. A distinguished feature of these
models is a crossing of the phantom divide. We reveal the nature of this
phenomena showing that it is caused by an equivalence of the initial non-local
model to a model with an infinite number of local fields some of which are
ghosts. Deformations of the model that admit exact solutions are constructed.
These deformations contain locking potentials that stabilize solutions.
Bouncing and accelerating solutions are presented.Comment: Minor corrections, references added, published in JHE
A Cloud-Based Framework for Machine Learning Workloads and Applications
[EN] In this paper we propose a distributed architecture to provide machine learning practitioners with a set of tools and cloud services that cover the whole machine learning development cycle: ranging from the models creation, training, validation and testing to the models serving as a service, sharing and publication. In such respect, the DEEP-Hybrid-DataCloud framework allows transparent access to existing e-Infrastructures, effectively exploiting distributed resources for the most compute-intensive tasks coming from the machine learning development cycle. Moreover, it provides scientists with a set of Cloud-oriented services to make their models publicly available, by adopting a serverless architecture and a DevOps approach, allowing an easy share, publish and deploy of the developed models.This work was supported by the project DEEP-Hybrid-DataCloud ``Designing and Enabling E-infrastructures for intensive Processing in a Hybrid DataCloud'' that has received funding from the European Union's Horizon 2020 Research and Innovation Programme under Grant 777435Lopez Garcia, A.; Marco De Lucas, J.; Antonacci, M.; Zu Castell, W.; David, M.; Hardt, M.; Lloret Iglesias, L.... (2020). A Cloud-Based Framework for Machine Learning Workloads and Applications. IEEE Access. 8:18681-18692. https://doi.org/10.1109/ACCESS.2020.2964386S1868118692
Proximity effect at superconducting Sn-Bi2Se3 interface
We have investigated the conductance spectra of Sn-Bi2Se3 interface junctions
down to 250 mK and in different magnetic fields. A number of conductance
anomalies were observed below the superconducting transition temperature of Sn,
including a small gap different from that of Sn, and a zero-bias conductance
peak growing up at lower temperatures. We discussed the possible origins of the
smaller gap and the zero-bias conductance peak. These phenomena support that a
proximity-effect-induced chiral superconducting phase is formed at the
interface between the superconducting Sn and the strong spin-orbit coupling
material Bi2Se3.Comment: 7 pages, 8 figure
Complete event-by-event α/γ(β) separation in a full-size TeO2 CUORE bolometer by simultaneous heat and light detection
The CUORE project began recently a search for neutrinoless double-beta decay () of Te with a (1 ton) TeO bolometer array. In this experiment, the background suppression relies essentially on passive shielding, material radiopurity and anti-coincidences. The lack of particle identification in CUORE makes decays at the detector surface the dominant background, at the level of 0.01 counts/(keV kg y) in the region of interest (-value of of the order of 2.5 MeV). In the present work we demonstrate, for the first time with a CUORE-size (555 cm) TeO bolometer and using the same technology as CUORE for the readout of the bolometric signals, an efficient particle discrimination (99.9\%) with a high acceptance of the signal (about 96\%). This unprecedented result was possible thanks to the superior performance (10 eV RMS baseline noise) of a Neganov-Luke-assisted germanium bolometer used to detect a tiny (70 eV) light signal dominated by ()-induced Cherenkov radiation in the TeO detector. The obtained results represent a major breakthrough towards the TeO-based version of CUPID, a ton-scale cryogenic experiment proposed as a follow-up to CUORE with particle identification
A detection system to measure muon-induced neutrons for direct Dark Matter searches
International audienceMuon-induced neutrons constitute a prominent background component in a number of low count rate experiments, namely direct searches for Dark Matter. In this work we describe a neutron detector to measure this background in an underground laboratory, the Laboratoire Souterrain de Modane. The system is based on 1 m of Gd-loaded scintillator and it is linked with the muon veto of the EDELWEISS-II experiment for coincident muon detection. The system was installed in autumn 2008 and passed since then a number of commissioning tests proving its full functionality. The data-taking is continuously ongoing and a count rate of the order of 1 muon-induced neutron per day has been achieved
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