4,450 research outputs found
Realistic calculations of nuclear disappearance lifetimes induced by neutron-antineutron oscillations
Realistic calculations of nuclear disappearance lifetimes induced by
neutron-antineutron oscillations are reported for oxygen and iron, using
antineutron nuclear potentials derived from a recent comprehensive analysis of
antiproton atomic X-ray and radiochemical data. A lower limit of 3.3 x 10E8 s
on the neutron-antineutron oscillation time is derived from the
Super-Kamiokande I new lower limit of 1.77 x 10E32 yr on the neutron lifetime
in oxygen. Antineutron scattering lengths in carbon and nickel, needed in trap
experiments using ultracold neutrons, are calculated from updated antinucleon
optical potentials at threshold, with results shown to be largely model
independent.Comment: version matching PRD publication, typos and references correcte
ΠΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΎΠ½Π½Π°Ρ ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠΊΠ° Π°Π½Π°Π»ΠΈΠ·Π° Π½Π°Π²ΡΠΊΠΎΠ² ΠΈ ΡΠΌΠ΅Π½ΠΈΠΉ ΠΊΠΎΠ½ΡΠΈΠ½Π³Π΅Π½ΡΠ° ΡΡΡΠ΄Π΅Π½ΡΠΎΠ² Π²ΡΡΡΠ΅Π³ΠΎ ΡΡΠ΅Π±Π½ΠΎΠ³ΠΎ Π·Π°Π²Π΅Π΄Π΅Π½ΠΈΡ
In the below article, the application of the fuzzy logical conclusion method is considered as decision-maker in the process of analyzing the students skills and abilities based on the requirements of potential employers, in order to reduce the time of the first interview for potential candidates on a vacant position. When analyzing the results of the assessment of the competence of university students, a certain degree of fuzziness arises. In modern practice, fuzzy logic is used in many different assessment methods, including questioning, interviewing, testing, descriptive method, classification method, pairwise comparison, rating method, business games competence models, and the like. Each of the methods has its advantages and disadvantages, but they are effective only as part of a unified personnel management system. As a method for implementing a systematic approach to the assessment of the contingent of students, it is proposed to use fuzzy logic, a mathematical apparatus that allows you to build a model of an object based on fuzzy judgments. The use of fuzzy logic, the mathematical apparatus of which allows you to build a model of the object, based on fuzzy reasoning and rules. The most important condition for creating such a model is to translate the fuzzy, qualitative assessments used by man into the language of mathematics, which will be understood by the computer. The most used are fuzzy inferences using the Mamdani and Sugeno methods. In a fuzzy inference of the Mamdani type, the value of the output variable is given by fuzzy terms, in the conclusion of the Sugeno type, as a linear combination of the input variables. Research in the field of application of fuzzy logic in socio-economic systems suggests that it can be used to assess the competencies of university students.Π Π΄Π°Π½Π½ΠΎΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΡΠ°ΡΡΠΌΠΎΡΡΠ΅Π½ΠΎ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ ΠΌΠ΅ΡΠΎΠ΄Π° Π½Π΅ΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π²ΡΠ²ΠΎΠ΄Π° Π΄Π»Ρ ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠΊΠΈ ΠΏΡΠΈΠ½ΡΡΠΈΡ ΡΠ΅ΡΠ΅Π½ΠΈΡ Π² Π·Π°Π΄Π°ΡΠ°Ρ
Π°Π½Π°Π»ΠΈΠ·Π° Π½Π°Π²ΡΠΊΠΎΠ² ΠΈ ΡΠΌΠ΅Π½ΠΈΠΉ ΠΊΠΎΠ½ΡΠΈΠ½Π³Π΅Π½ΡΠ° ΡΡΡΠ΄Π΅Π½ΡΠΎΠ² ΠΈΡΡ
ΠΎΠ΄Ρ ΠΈΠ· ΡΡΠ΅Π±ΠΎΠ²Π°Π½ΠΈΠΉ ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»ΡΠ½ΡΡ
ΡΠ°Π±ΠΎΡΠΎΠ΄Π°ΡΠ΅Π»Π΅ΠΉ, Ρ ΡΠ΅Π»ΡΡ ΡΠΌΠ΅Π½ΡΡΠ΅Π½ΠΈΡ Π²ΡΠ΅ΠΌΠ΅Π½ΠΈ Π½Π° ΠΏΠ΅ΡΠ²ΠΈΡΠ½ΡΡ ΠΎΠ±ΡΠ°Π±ΠΎΡΠΊΡ ΠΈΠ½ΡΠΎΡΠΌΠ°ΡΠΈΠΈ ΠΊΠ°ΡΠ°ΡΠ΅Π»ΡΠ½ΠΎ ΠΏΠΎΡΠ΅Π½ΡΠΈΠ°Π»ΡΠ½ΡΡ
ΠΊΠ°Π½Π΄ΠΈΠ΄Π°ΡΠΎΠ² Π½Π° Π²Π°ΠΊΠ°Π½ΡΠ½ΡΡ Π΄ΠΎΠ»ΠΆΠ½ΠΎΡΡΡ. ΠΡΠΈ Π°Π½Π°Π»ΠΈΠ·Π΅ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠΎΠ² ΠΎΡΠ΅Π½ΠΊΠΈ ΠΊΠΎΠΌΠΏΠ΅ΡΠ΅Π½ΡΠ½ΠΎΡΡΠΈ ΡΡΡΠ΄Π΅Π½ΡΠΎΠ² Π²ΡΠ·ΠΎΠ² Π²ΠΎΠ·Π½ΠΈΠΊΠ°Π΅Ρ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½Π½Π°Ρ ΡΡΠ΅ΠΏΠ΅Π½Ρ Π½Π΅ΡΠ΅ΡΠΊΠΎΡΡΠΈ. Π ΡΠΎΠ²ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ ΠΏΡΠ°ΠΊΡΠΈΠΊΠ΅ Π½Π΅ΡΠ΅ΡΠΊΠ°Ρ Π»ΠΎΠ³ΠΈΠΊΠ° ΠΏΡΠΈΠΌΠ΅Π½ΡΠ΅ΡΡΡ Π²ΠΎ ΠΌΠ½ΠΎΠ³ΠΈΡ
ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΠΌΠ΅ΡΠΎΠ΄Π°Ρ
ΠΎΡΠ΅Π½ΠΊΠΈ, Π² ΡΠΎΠΌ ΡΠΈΡΠ»Π΅ Π°Π½ΠΊΠ΅ΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅, ΠΈΠ½ΡΠ΅ΡΠ²ΡΡ, ΡΠ΅ΡΡΠΈΡΠΎΠ²Π°Π½ΠΈΠ΅, ΠΎΠΏΠΈΡΠ°ΡΠ΅Π»ΡΠ½ΡΠΉ ΠΌΠ΅ΡΠΎΠ΄, ΠΌΠ΅ΡΠΎΠ΄ ΠΊΠ»Π°ΡΡΠΈΡΠΈΠΊΠ°ΡΠΈΠΈ, ΠΏΠ°ΡΠ½ΠΎΠ΅ ΡΡΠ°Π²Π½Π΅Π½ΠΈΠ΅, ΡΠ΅ΠΉΡΠΈΠ½Π³ΠΎΠ²ΡΠΉ ΠΌΠ΅ΡΠΎΠ΄, Π΄Π΅Π»ΠΎΠ²ΡΠ΅ ΠΈΠ³ΡΡ ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΊΠΎΠΌΠΏΠ΅ΡΠ΅Π½ΡΠ½ΠΎΡΡΠΈ ΠΈ ΡΠΎΠΌΡ ΠΏΠΎΠ΄ΠΎΠ±Π½ΠΎΠ΅. ΠΠ°ΠΆΠ΄ΡΠΉ ΠΈΠ· ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ² ΠΈΠΌΠ΅Π΅Ρ ΡΠ²ΠΎΠΈ ΠΏΡΠ΅ΠΈΠΌΡΡΠ΅ΡΡΠ²Π° ΠΈ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΊΠΈ, Π½ΠΎ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½Ρ ΠΎΠ½ΠΈ ΡΠΎΠ»ΡΠΊΠΎ Π² ΡΠΎΡΡΠ°Π²Π΅ Π΅Π΄ΠΈΠ½ΠΎΠΉ ΡΠΈΡΡΠ΅ΠΌΡ ΡΠΏΡΠ°Π²Π»Π΅Π½ΠΈΡ ΠΏΠ΅ΡΡΠΎΠ½Π°Π»ΠΎΠΌ. ΠΠ°ΠΊ ΠΌΠ΅ΡΠΎΠ΄ Π΄Π»Ρ ΡΠ΅Π°Π»ΠΈΠ·Π°ΡΠΈΠΈ ΡΠΈΡΡΠ΅ΠΌΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄Π° ΠΊ ΠΎΡΠ΅Π½ΠΊΠ΅ ΠΊΠΎΠ½ΡΠΈΠ½Π³Π΅Π½ΡΠ° ΡΡΡΠ΄Π΅Π½ΡΠΎΠ² ΠΏΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½ΠΎ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°ΡΡ Π½Π΅ΡΠ΅ΡΠΊΡΡ Π»ΠΎΠ³ΠΈΠΊΡ, ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΉ Π°ΠΏΠΏΠ°ΡΠ°Ρ, ΠΊΠΎΡΠΎΡΡΠΉ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΠΏΠΎΡΡΡΠΎΠΈΡΡ ΠΌΠΎΠ΄Π΅Π»Ρ ΠΎΠ±ΡΠ΅ΠΊΡΠ°, ΠΎΡΠ½ΠΎΠ²Π°Π½Π½ΡΡ Π½Π° Π½Π΅ΡΠ΅ΡΠΊΠΈΡ
ΡΡΠΆΠ΄Π΅Π½ΠΈΡΡ
. ΠΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ Π½Π΅ΡΠ΅ΡΠΊΠΎΠΉ Π»ΠΎΠ³ΠΈΠΊΠΈ, ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΈΠΉ Π°ΠΏΠΏΠ°ΡΠ°Ρ ΠΊΠΎΡΠΎΡΠΎΠΉ ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΠΏΠΎΡΡΡΠΎΠΈΡΡ ΠΌΠΎΠ΄Π΅Π»Ρ ΠΎΠ±ΡΠ΅ΠΊΡΠ°, ΠΎΡΠ½ΠΎΠ²ΡΠ²Π°ΡΡΡ Π½Π° Π½Π΅ΡΠ΅ΡΠΊΠΈΡ
ΡΠ°ΡΡΡΠΆΠ΄Π΅Π½ΠΈΡΡ
ΠΈ ΠΏΡΠ°Π²ΠΈΠ»Π°Ρ
. ΠΠ°ΠΆΠ½Π΅ΠΉΡΠ΅Π΅ ΡΡΠ»ΠΎΠ²ΠΈΠ΅ ΡΠΎΠ·Π΄Π°Π½ΠΈΡ ΡΠ°ΠΊΠΎΠΉ ΠΌΠΎΠ΄Π΅Π»ΠΈ Π·Π°ΠΊΠ»ΡΡΠ°Π΅ΡΡΡ Π² ΡΠΎΠΌ, ΡΡΠΎΠ±Ρ ΠΏΠ΅ΡΠ΅Π²Π΅ΡΡΠΈ Π½Π΅ΡΠ΅ΡΠΊΠΈΠ΅, ΠΊΠ°ΡΠ΅ΡΡΠ²Π΅Π½Π½ΡΠ΅ ΠΎΡΠ΅Π½ΠΊΠΈ, ΠΏΡΠΈΠΌΠ΅Π½ΡΠ΅ΠΌΡΠ΅ ΡΠ΅Π»ΠΎΠ²Π΅ΠΊΠΎΠΌ, Π½Π° ΡΠ·ΡΠΊ ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΠΊΠΈ, ΠΊΠΎΡΠΎΡΠ°Ρ Π±ΡΠ΄Π΅Ρ ΠΏΠΎΠ½ΡΡΠ½Π° Π²ΡΡΠΈΡΠ»ΠΈΡΠ΅Π»ΡΠ½ΠΎΠΉ ΠΌΠ°ΡΠΈΠ½Π΅. ΠΠ°ΠΈΠ±ΠΎΠ»Π΅Π΅ ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΠ΅ΠΌΡΠΌΠΈ ΡΠ²Π»ΡΡΡΡΡ Π½Π΅ΡΠ΅ΡΠΊΠΈΠ΅ Π²ΡΠ²ΠΎΠ΄Ρ Ρ ΠΏΠΎΠΌΠΎΡΡΡ ΡΠΏΠΎΡΠΎΠ±ΠΎΠ² ΠΠ°ΠΌΠ΄Π°Π½ΠΈ ΠΈ Π‘ΡΠ³Π΅Π½ΠΎ. Π Π½Π΅ΡΠ΅ΡΠΊΠΎΠΌ Π²ΡΠ²ΠΎΠ΄Π΅ ΡΠΈΠΏΠ° ΠΠ°ΠΌΠ΄Π°Π½ΠΈ Π·Π½Π°ΡΠ΅Π½ΠΈΠ΅ Π²ΡΡ
ΠΎΠ΄Π½ΠΎΠΉ ΠΏΠ΅ΡΠ΅ΠΌΠ΅Π½Π½ΠΎΠΉ Π·Π°Π΄Π°ΡΡΡΡ Π½Π΅ΡΠ΅ΡΠΊΠΈΠΌΠΈ ΡΠ΅ΡΠΌΠ°ΠΌΠΈ, Π² Π·Π°ΠΊΠ»ΡΡΠ΅Π½ΠΈΠΈ ΡΠΈΠΏΠ° Π‘ΡΠ³Π΅Π½ΠΎ β ΠΊΠ°ΠΊ Π»ΠΈΠ½Π΅ΠΉΠ½Π°Ρ ΠΊΠΎΠΌΠ±ΠΈΠ½Π°ΡΠΈΡ Π²Ρ
ΠΎΠ΄Π½ΡΡ
ΠΏΠ΅ΡΠ΅ΠΌΠ΅Π½Π½ΡΡ
. ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ Π² ΠΎΠ±Π»Π°ΡΡΠΈ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ Π½Π΅ΡΠ΅ΡΠΊΠΎΠΉ Π»ΠΎΠ³ΠΈΠΊΠΈ Π² ΡΠΎΡΠΈΠΎΡΠΊΠΎΠ½ΠΎΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
ΡΠΈΡΡΠ΅ΠΌΠ°Ρ
ΠΏΠΎΠ·Π²ΠΎΠ»ΡΡΡ Π³ΠΎΠ²ΠΎΡΠΈΡΡ ΠΎ Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΠΈ Π΅Π΅ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΡ Π΄Π»Ρ ΠΎΡΠ΅Π½ΠΊΠΈ ΠΊΠΎΠΌΠΏΠ΅ΡΠ΅Π½ΡΠΈΠΉ ΡΡΡΠ΄Π΅Π½ΡΠΎΠ² Π²ΡΠ·ΠΎΠ²
Limits on nu_e and anti-nu_e disappearance from Gallium and reactor experiments
The deficit observed in the Gallium radioactive source experiments is
interpreted as a possible indication of the disappearance of electron
neutrinos. In the effective framework of two-neutrino mixing we obtain
and . The compatibility of this result with the data of the Bugey and
Chooz reactor short-baseline antineutrino disappearance experiments is studied.
It is found that the Bugey data present a hint of neutrino oscillations with
and , which is compatible with the Gallium allowed region of the
mixing parameters. This hint persists in the combined analyses of Bugey and
Chooz data, of Gallium and Bugey data, and of Gallium, Bugey, and Chooz data.Comment: 21 pages. Final version to be published in Phys. Rev.
OPTIMIZATION OF THE HOT-ELECTRON BOLOMETER AND A CASCADE QUASIPARTICLE AMPLIFIER FOR SPACE ASTRONOMY
Ultra low noise bolometers are required for space - based astronomical observations. Extremely sensitive detectors are necessary for a deep full-sky survey of distant extragalactic sources in the submillimeter-wave region corresponding to the extraterrestrial background spectrum minimum. A deep full-sky survey is the main goal of the Submillimetron project of the cryogenically cooled telescope on the International Space Station [1,2], project CIRCE (NASA) and other projects. Detection of faint sources involvves wide-band continuum observation using direct detectors (bolometers) that are not restricted by the quantum noise of indirect heterodyne receivers.
Theoretical estimations and preliminary experiments show that it is possible to realize the necessary sensitivity of 10-18 - 10-19 W/Hz1/2 with a novel concept of the antenna-coupled microbolometers at temperatures 0.1 K. Additional advantages of such detectors are the possibility to operate with a wide range of background load, easy integration in arrays, and direct possibility of polarization measurements
Charged lepton-nucleus inelastic scattering at high energies
The composite model is constructed to describe inelastic high-energy
scattering of muons and taus in standard rock. It involves photonuclear
interactions at low as well as moderate processes and the deep
inelastic scattering (DIS). In the DIS region the neutral current contribution
is taken into consideration. Approximation formulas both for the muons and tau
energy loss in standard rock are presented for wide energy range.Comment: 5 pages, 4 figures. Presented at 19th European Cosmic Ray Symposium
(ECRS 2004), Florence, Italy, 30 Aug - 3 Sep 2004. Submitted to
Int.J.Mod.Phys.
Metastable Voltage States of Coupled Josephson Junctions
We investigate a chain of capacitively coupled Josephson junctions in the
regime where the charging energy dominates over the Josephson coupling,
exploiting the analogy between this system and a multi-dimensional crystal. We
find that the current-voltage characteristic of the current-driven chain has a
staircase shape, beginning with an (insulating) non-zero voltage plateau at
small currents. This behavior differs qualitatively from that of a single
junction, which should show Bloch oscillations with vanishing dc voltage. The
simplest system where this effect can be observed consists of three grains
connected by two junctions. The theory explains the results of recent
experiments on Josephson junction arrays.Comment: 5 pages, 4 figures include
The Supersymmetric Stueckelberg Mass and Overcoming the Fayet-Iliopoulos Mechanism for Breaking Symmetry
Gauge invariant generation of mass for supersymmetric U(1) vector field
through use of a chiral Stueckelberg superfield is considered. When a
Fayet-Iliopoulos D term is also present, no breaking of supersymmetry ever
occurs so long as the Stueckelberg mass is not zero. A moduli space in which
gauge symmetry is spontaneously broken arises in this case
Chandra detection of extended X-ray emission from the recurrent nova RS Ophiuchi
Radio, infrared, and optical observations of the 2006 eruption of the
symbiotic recurrent nova RS Ophiuchi (RS Oph) showed that the explosion
produced non-spherical ejecta. Some of this ejected material was in the form of
bipolar jets to the east and west of the central source. Here we describe Xray
observations taken with the Chandra X-ray Observatory one and a half years
after the beginning of the outburst that reveal narrow, extended structure with
a position angle of approximately 300 degrees (east of north). Although the
orientation of the extended feature in the X-ray image is consistent with the
readout direction of the CCD detector, extensive testing suggests that the
feature is not an artifact. Assuming it is not an instrumental effect, the
extended X-ray structure shows hot plasma stretching more than 1,900 AU from
the central binary (taking a distance of 1.6 kpc). The X-ray emission is
elongated in the northwest direction - in line with the extended infrared
emission and some minor features in the published radio image. It is less
consistent with the orientation of the radio jets and the main bipolar optical
structure. Most of the photons in the extended X-ray structure have energies of
less than 0.8 keV. If the extended X-ray feature was produced when the nova
explosion occurred, then its 1".2 length as of 2007 August implies that it
expanded at an average rate of more than 2 mas/d, which corresponds to a flow
speed of greater than 6,000 km/s (d/1.6 kpc) in the plane of the sky. This
expansion rate is similar to the earliest measured expansion rates for the
radio jets.Comment: accepted in Ap
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