309 research outputs found
A Simulation Study on the Effect of Cavity Shapes on the Penetration of Linear Shaped Charges with Curved Liners
The finite element models of curved-liner shaped charges penetrating aluminum-alloy thin plates were constructed with the ANSYS/LS-DYNA software to analyze the effect of cavity shapes on the charge penetration with curved liners. The cavity height, radius, and spatial dimensions were numerically simulated. Simulation results indicate that these properties are important factors in determining the penetration of curved-liner charges. The penetration depth exhibits an initial increase followed by a decrease with the fixed cavity radius. When the cavity height is fixed, the penetration depth decreases with the cavity radius. When the cavity is semicircular, the penetration depth first increases and then decreases with the cavity radius and height.ΠΠΎΡΡΡΠΎΠ΅Π½Ρ ΠΊΠΎΠ½Π΅ΡΠ½ΠΎΡΠ»Π΅ΠΌΠ΅Π½ΡΠ½ΡΠ΅ ΠΌΠΎΠ΄Π΅Π»ΠΈ ΠΊΡΠΌΡΠ»ΡΡΠΈΠ²Π½ΡΡ
Π·Π°ΡΡΠ΄ΠΎΠ² ΡΠΎ ΡΠ»ΠΎΠΆΠ½ΠΎΠΏΡΠΎΡΠΈΠ»ΡΠ½ΠΎΠΉ ΠΎΠ±Π»ΠΈΡΠΎΠ²ΠΊΠΎΠΉ, ΠΏΡΠΎΠ½ΠΈΠΊΠ°ΡΡΠΈΡ
ΡΠ΅ΡΠ΅Π· ΡΠΎΠ½ΠΊΠΈΠ΅ ΠΏΠ»Π°ΡΡΠΈΠ½Ρ ΠΈΠ· Π°Π»ΡΠΌΠΈΠ½ΠΈΠ΅Π²ΠΎΠ³ΠΎ ΡΠΏΠ»Π°Π²Π°. ΠΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΎ ΠΏΡΠΎΠ³ΡΠ°ΠΌΠΌΠ½ΠΎΠ΅ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠ΅Π½ΠΈΠ΅ ANSYS/LS-DYNA Π΄Π»Ρ Π°Π½Π°Π»ΠΈΠ·Π° Π²Π»ΠΈΡΠ½ΠΈΡ ΡΠΎΡΠΌΡ Π²ΡΠ΅ΠΌΠΊΠΈ Π½Π° ΠΈΡ
ΠΏΡΠΎΠ½ΠΈΡΠ°Π΅ΠΌΠΎΡΡΡ. ΠΡΠΏΠΎΠ»Π½Π΅Π½Ρ ΡΠΈΡΠ»Π΅Π½Π½ΡΠ΅ ΡΠ°ΡΡΠ΅ΡΡ Π²ΡΡΠΎΡΡ, ΡΠ°Π΄ΠΈΡΡΠ° ΠΈ ΠΏΡΠΎΡΡΡΠ°Π½ΡΡΠ²Π΅Π½Π½ΡΡ
ΡΠ°Π·ΠΌΠ΅ΡΠΎΠ² Π²ΡΠ΅ΠΌΠΊΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΡΠΎ ΡΡΠΈ Ρ
Π°ΡΠ°ΠΊΡΠ΅ΡΠΈΡΡΠΈΠΊΠΈ ΡΠ²Π»ΡΡΡΡΡ Π²Π°ΠΆΠ½ΡΠΌΠΈ ΡΠ°ΠΊΡΠΎΡΠ°ΠΌΠΈ ΠΏΡΠΈ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΠΈ ΠΏΡΠΎΠ½ΠΈΡΠ°Π΅ΠΌΠΎΡΡΠΈ Π·Π°ΡΡΠ΄ΠΎΠ². ΠΠ»ΡΠ±ΠΈΠ½Π° ΠΏΡΠΎΠ½ΠΈΠΊΠ½ΠΎΠ²Π΅Π½ΠΈΡ ΡΠ²Π΅Π»ΠΈΡΠΈΠ²Π°Π΅ΡΡΡ, Π° Π·Π°ΡΠ΅ΠΌ ΡΠΌΠ΅Π½ΡΡΠ°Π΅ΡΡΡ Ρ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΠ΅ΠΌ Π²ΡΡΠΎΡΡ Π²ΡΠ΅ΠΌΠΊΠΈ ΠΏΡΠΈ ΠΏΠΎΡΡΠΎΡΠ½Π½ΠΎΠΌ ΡΠ°Π΄ΠΈΡΡΠ΅. ΠΡΠΈ ΡΠΈΠΊΡΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ Π²ΡΡΠΎΡΠ΅ Π³Π»ΡΠ±ΠΈΠ½Π° ΠΏΡΠΎΠ½ΠΈΠΊΠ½ΠΎΠ²Π΅Π½ΠΈΡ ΡΠΌΠ΅Π½ΡΡΠ°Π΅ΡΡΡ Ρ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΠ΅ΠΌ ΡΠ°Π΄ΠΈΡΡΠ°. ΠΡΠΈ ΠΏΠΎΠ»ΡΠΎΠΊΡΡΠΆΠ½ΠΎΠΉ Π²ΡΠ΅ΠΌΠΊΠ΅ Π³Π»ΡΠ±ΠΈΠ½Π° ΠΏΡΠΎΠ½ΠΈΠΊΠ½ΠΎΠ²Π΅Π½ΠΈΡ ΡΠ²Π΅Π»ΠΈΡΠΈΠ²Π°Π΅ΡΡΡ, Π·Π°ΡΠ΅ΠΌ ΡΠΌΠ΅Π½ΡΡΠ°Π΅ΡΡΡ Ρ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΠ΅ΠΌ Π΅Π΅ ΡΠ°Π΄ΠΈΡΡΠ° ΠΈ Π²ΡΡΠΎΡΡ
Measurements of the observed cross sections for exclusive light hadrons containing at , 3.650 and 3.6648 GeV
By analyzing the data sets of 17.3, 6.5 and 1.0 pb taken,
respectively, at , 3.650 and 3.6648 GeV with the BES-II
detector at the BEPC collider, we measure the observed cross sections for
, , ,
and at the three energy
points. Based on these cross sections we set the upper limits on the observed
cross sections and the branching fractions for decay into these
final states at 90% C.L..Comment: 7 pages, 2 figure
Partial wave analysis of J/\psi \to \gamma \phi \phi
Using events collected in the BESII detector, the
radiative decay is
studied. The invariant mass distribution exhibits a near-threshold
enhancement that peaks around 2.24 GeV/.
A partial wave analysis shows that the structure is dominated by a
state () with a mass of
GeV/ and a width of GeV/. The
product branching fraction is: .Comment: 11 pages, 4 figures. corrected proof for journa
Direct Measurements of Absolute Branching Fractions for D0 and D+ Inclusive Semimuonic Decays
By analyzing about 33 data sample collected at and around 3.773
GeV with the BES-II detector at the BEPC collider, we directly measure the
branching fractions for the neutral and charged inclusive semimuonic decays
to be and , and determine the ratio of the two branching
fractions to be
A study of charged kappa in
Based on events collected by BESII, the decay
is studied. In the invariant mass
spectrum recoiling against the charged , the charged
particle is found as a low mass enhancement. If a Breit-Wigner function of
constant width is used to parameterize the kappa, its pole locates at MeV/. Also in this channel,
the decay is observed for the first time.
Its branching ratio is .Comment: 14 pages, 4 figure
Measurements of the observed cross sections for exclusive light hadron production in e^+e^- annihilation at \sqrt{s}= 3.773 and 3.650 GeV
By analyzing the data sets of 17.3 pb taken at GeV
and 6.5 pb taken at GeV with the BESII detector at the
BEPC collider, we have measured the observed cross sections for 12 exclusive
light hadron final states produced in annihilation at the two energy
points. We have also set the upper limits on the observed cross sections and
the branching fractions for decay to these final states at 90%
C.L.Comment: 8 pages, 5 figur
Measurements of psi(2S) decays to octet baryon-antibaryon pairs
With a sample of 14 million psi(2S) events collected by the BESII detector at
the Beijing Electron Positron Collider (BEPC), the decay channels psi(2S)->p
p-bar, Lambda Lambda-bar, Sigma0 Sigma0-bar, Xi Xi-bar are measured, and their
branching ratios are determined to be (3.36+-0.09+-0.24)*10E-4,
(3.39+-0.20+-0.32)*10E-4, (2.35+-0.36+-0.32)*10E-4, (3.03+-0.40+-0.32)*10E-4,
respectively. In the decay psi(2S)->p p-bar, the angular distribution parameter
alpha is determined to be 0.82+-0.17+-0.04.Comment: 8 pages, 8 figure
Partial Wave Analysis of
BES data on are presented. The
contribution peaks strongly near threshold. It is fitted with a
broad resonance with mass MeV, width MeV. A broad resonance peaking at 2020 MeV is also required
with width MeV. There is further evidence for a component
peaking at 2.55 GeV. The non- contribution is close to phase
space; it peaks at 2.6 GeV and is very different from .Comment: 15 pages, 6 figures, 1 table, Submitted to PL
Measurements of the observed cross sections for e+e -> exclusive light hadrons containing K^S_0 meson at \sqrt{s} = 3.773 and 3.650 GeV
By analyzing the data sets of 17.3 pb taken at GeV
and of 6.5 pb taken at GeV with the BES-II detector at
the BEPC collider, we measure the observed cross sections for the exclusive
light hadron final states of , ,
, ,
and produced in
annihilation at the two energy points. We set the upper limits on the
observed cross sections and the branching fractions for decay to
these final states at 90% C.L..Comment: 6 pages, 1 figur
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