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1.
A recursive formulation is proposed for the method of reverberation-ray matrix (MRRM) to exactly analyze the free vibration
of a multi-span continuous rectangular Kirchhoff plate, which has two opposite simply-supported edges. In contrast to the
traditional MRRM, numerical stability is achieved by using the present new formulation for high-order frequencies or/and for
plates with large span-to-width ratios. The heavy computational cost of storage and memory are also cut down. An improved
recursive formulation is further proposed by modifying the iterative formula to reduce the matrix inversion operations. Numerical
examples are finally given to demonstrate the effectiveness and efficiency of the proposed recursive formulae.
Supported by the National Natural Science Foundation of China (Grant Nos. 10725210, 10832009, and 10432030), the National
Basic Research Program of China (Grant No. 2009CB623204), the Specialized Research Fund for the Doctoral Program of Higher
Education (Grant No. 20060335107), and the Program for New Century Excellent Talents in University (Grant No. NCET-05-0510) 相似文献
2.
E. A. Chinnov S. M. Kharlamov A. V. Saprykina O. V. Zhukovskaya 《Thermophysics and Aeromechanics》2007,14(2):241-246
The fluorescence method was used to measure the instantaneous thickness field of the falling nonisothermal water film. The
process of rivulet formation in a heated film was registered.
Measurement averaging allowed determination of the degree of transverse deformation of a film. In the lower half of the heater
within the interrivulet zone of the non-isothermal film, the wave amplitude decreases with a rise of the heat flux and reduction
of the average thickness. Two zones of the heat flux effect on liquid film deformation were distinguished. At low heat fluxes,
the film flow is weakly deformed. At high heat fluxes the thermal-capillary forces provide formation of rivulets and a thin
film between them.
The work was financially supported by the President of RF (NSh-6749.2006.8), Russian Foundation for Basic Research (Grants
Nos. 05-08-33325-a, 06-01-00360-a), National Center on Science and Innovations (State contract No. 02.438.11.7002), and SB
RAS (Interdisciplinary Integration Project No. 111). 相似文献
3.
We analyzed the spectrum of the 187Re beta decay, obtained with a cryogenic microcalorimeter, searching for heavy neutrinos in the mass range 50-1000 eV. No evidence has been found for them and the upper limits on the mixing angle with a zero-mass neutrino are reported. Upper limits of 9x10(-3) at 1000 eV/c(2), 1.2x10(-2) at 500 eV/c(2), 4.4x10(-2) at 200 eV/c(2), and 0.116 at 100 eV/c(2) at 95% C.L. have been obtained. These upper limits are a factor of 2 to 4 lower than the current limits reported in the literature. 相似文献
4.
Here we consider one-dimensional heating of a layer of gray semitransparent medium by an outer source of radiation and convection.
The sample boundaries reflect, absorb (radiate), and transmit radiation. It is shown that heating dynamics and character of
temperature fields depend significantly on optic parameters of the boundaries.
The work was financially supported by the President of the Russian Federation (MK-601.2008.8) and Russian Foundation for Basic
Research (Grant No. 08-08-00527-a). 相似文献
5.
S. S. Vorontsov V. N. Zudov P. K. Tretyakov A. V. Tupikin 《Thermophysics and Aeromechanics》2006,13(4):615-621
Results of an experimental study of the ignition dynamics of propane-air premixed flows under pulsed-periodic laser irradiation
are reported. Ignition of homogeneous flows emanating into free atmosphere is considered. A comparative analysis of experimental
and predicted delay times for the ignition for a medium at rest is given.
This work was supported by the President of the Russian Federation (Grant No. NSh-8597. 2006.1), by the Russian Foundation
for Basic Research (Grant No. 05-01-00560) and by the Presidium of the Russian Academy of Sciences (under the Program “Fundamental
Problems in Magnetoplasma Aerodynamics”). 相似文献
6.
Signal structure of the Chinese Area Positioning System 总被引:8,自引:8,他引:0
Proper signal structure is very important in the navigation, positioning, and time services of a satellite navigation system.
In this paper, the carrier wave characteristics, ranging code functions, BOC modulation, navigation data rate, the error-correcting
methods, and signal channel resource allocation are discussed in terms of the technical characteristics of the transforming
satellite navigation system and the resources of communication satellites. The results show that dual-frequency of C band
in the Chinese Area Positioning System (CAPS), compound ranging code, a combination of the coarse code and precise code, BOC
modulation, separate-channel transmission of different users are compatible with the satellite navigation system at present.
The experiments show that the current signal structure can meet the demand of CAPS.
Supported by the Major Knowledge Innovation Programs of the Chinese Academy of Sciences (Grant No. KGCX1-21), the National
High Technology Research and Development Program of China (Grant No. 2004AA105030), the National Natural Science Foundation
of China (Grant No. 10453001), and the Major State Basic Research Development Program of China (Grant No. 2007CB815502) 相似文献
7.
The effect of artificial perturbations on structure formation in the water film flow over a vertical plate with a heater was
studied experimentally. To measure the film thickness an eight-channel capacitance probe was used. It is shown that artificial
perturbations on the liquid film surface can change the distance between rivulets from the values corresponding to the thermocapillary-wave
regime of rivulet formation to the values related to the thermocapillary regime. The distance between the rivulets can be
changed at Reynolds numbers higher than those corresponding to the thermocapillary regime. Artificial perturbations do not
change significantly the relative amplitude of large waves, but they affect the character of amplitude dependence on the heat
flux density.
The work was financially supported by the Russian Foundation for Basic Research (Grants Nos. 05-08-33325-a, 06-01-00360-a)
and SB RAS (Interdisciplinary Integration Project No. 111). 相似文献
8.
9.
V. G. Chernorai V. V. Kozlov L. L. Loefdahl G. R. Grek H. H. Chun 《Thermophysics and Aeromechanics》2006,13(1):67-74
Results of experimental investigations of the nonlinear stage of sinusoidal and varicose instability of a streaky structure,
which leads to multiplication of streaky structures and origination of coherent structures (such as Λ-structures), are presented.
Riblets suppress the intensity of streaky structures, stabilize the flow against the development of the secondary high-frequency
instability of streaky structures, and, for this reason, delay spatial turbulization of the flow. The results of these investigations
can be useful for understanding the flow structure in such situations and for possible controlling of the coherent structures
aimed at flow stabilization.
This work was supported by the President of the Russian Federation (Grant No. NSh-964.2003.1) and by the Russian Foundation
for Basic Research (Grant No. 05-01-00034). 相似文献
10.
Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that,
at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise
model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise
nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different
times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.
Supported by the National Natural Science Foundation of China (Grant No. 10734100), the Knowledge Innovation Program of the
Chinese Academy of Sciences (Grant No. KZCX1-YW-12-2), the National Basic Research Program of China (Grant No. 2007CB209603),
and the Open Foundation of China National Petroleum Corporation Key Laboratory (Grant No. GPKL0804) 相似文献
11.
Temperature (77–330 K), spectral (250–850 nm), and baric (0-500 bar) dependences of the birefringence Δny of (NH4(2BeF4 crystals are investigated. The influence of uniaxial mechanical pressures on the inversion of the birefringence Δny of (NH4(2BeF4 crystals is studied. A new method and a device to measure uniaxial stresses of up to 500 bar in the temperature range of
300–315 K based on a temperature-spectral-baric diagram of the sign inversion for the birefringence Δny of (NH4)2BeF4 crystals are proposed.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 4, pp. 551–554, July–August, 1997. 相似文献
12.
T. M. Zaboronkova A. V. Kostrov A. V. Kudrin A. I. Smirnov A. A. Shaikin 《Radiophysics and Quantum Electronics》1996,39(2):132-139
The role of different sections of the spatial spectrum of whistler waves excited by a loop antenna in the formation of an electromagnetic field structure is investigated experimentally and theoretically. Primary attention is given to the intermediate range of distances between the source and the observation point.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 39, No. 2, pp. 192–202, February, 1996.T. M. Zaboronkova, A. V. Kostrov, A. I. Smirnov, and A. A. Shaikin are grateful to The Russian Foundation for Fundamental Research (Grant No.94-02-05447a) and the George Soros International Foundation (Grant No. NOP 300) for financial support. A. V. Kudrin is grateful to the Russian Fund for Fundamental Research (Grant No. 96-02-18666) for financial support. 相似文献
13.
V. G. Chernoray V. V. Kozlov L. Loefdahl P. R. Pratt 《Thermophysics and Aeromechanics》2006,13(2):213-220
The nonlinear stage of breakdown to turbulence is a strongly three-dimensional process and represents a difficult task for
experimental studies. Investigation of laminar-turbulent transition in aerospace applications additionally involves a complex
base-flow with pressure gradients and secondary velocity components resulting in successive increase of necessary measurements.
The developed hot-wire visualization technique offers a possibility for an advanced analysis whilst retaining the advantages
of traditional visualization methods and is especially suitable for resolving such complex flows.
Thanks are due to the Royal Swedish Academy of Sciences, the Swedish Energy Agency (Energimyndigheten). The work was financially
supported by the President of the Russian Federation (Grant No. NSh-964.2003.1), the Russian Foundation for Basic Research
(Grant No. 05-01-00034) and Ministry of Education and Sciences of the Russian Federation (Grant No. RNP.2.1.2.3370). 相似文献
14.
A new concept and its methodology for studying human meridians are presented based on rigorous and scientific observation
on the objective existence of human meridians in view of biomedical optics. According to this methodology, the infrared radiant
characteristics of acupuncture meridians over human body and the optical transport properties of light propagating along the
meridian are reported. This study, thus, confirms the existence of acupuncture meridians, sheds new light on an approach to
investigation of human meridians and offers a new perspective in understanding the potential meridian functions such as energy
and information transfer and physiological regulation.
Supported by the National Key Basic Research Program of China (Grant No. 2006CB504505), the National Natural Science Foundation
of China (Grant Nos. 60578056 and 30572309), the Science Research Foundation of Ministry of Health & United Fujian Provincial
Health and Education Project for Tackling the Key Research of China (Grant No. WKJ2005-2-004), the Young Scientists and Technicians
Innovation Project of Fujian Province (Grant No. 2007F3026), and the Fund from Fujian Normal University (Grant No. 2008100218) 相似文献
15.
P. Mierzyński K. Pomorski 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,21(3):311-314
Strutinsky shell corrections for the cesium-coated fullerenes were investigated. The single particle levels of electrons are
obtained using the spherical mean-field potential of a shifted Wood-Saxon type. The parameters of the potential are adjusted
to reproduce the experimental ionization energies of the Cs(N) clusters and the magic numbers observed in their photo-ionization spectra of the C60Cs(N) aggregates.
Received 24 May 2002 / Received in final form 9 July 2002 Published online 15 October 2002
RID="*"
ID="*"This work has been partly supported by the Polish Committee for Scientific Research under Contract No. 2P03B 115 19
and by the Program of Scientific Exchange between the IN2P3-France and the Polish Research Institution No. 99-95.
RID="b"
ID="b"e-mail: Krzysztof.Pomorski@umcs.lublin.pl 相似文献
16.
This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between
the dilution of precision (DOP) of four-dimensional (4D) calculation including satellite clock errors and ephemeris errors
and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS
shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock
errors and ephemeris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock
errors are separated in a master station with time synchronization, and all the remaining pseudo-range errors after the satellite
clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis
of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid
for GEO constellation.
Supported by the National Natural Science Foundation of China (Grant No. 10778715), the National Key Basic Research Development
Program of China (Grant No. 2007CB815502), and the Scientific Research Fund of Hunan Provincial Education Department (Grant
No. 08B039) 相似文献
17.
Analysis of the forces acting on the saltating particles in the coupled wind-sand-electricity fields
Based on the theoretical model describing the saltation of sand particles in the coupled wind-sand-electricity fields, the
numerical simulations of the forces acting on saltating particles, such as the aerodynamic drag force, Magnus effect, Saffman
force and electrostatic force, are analyzed in comparison to the gravity force of the particles in the steady windblown sand
movement. Furthermore, the laws of the above forces vary with the friction velocity, the diameter of the sand particle, the
initial angular velocity and the lift-off velocity are discussed.
Supported by the National Natural Science Foundation of China (Grant Nos. 10772075 and 10772074), the Key Project of the National
Natural Science Foundation of China (Grant No.10532040), and the Program for New Century Excellent Talents in University (Grant
No. NCET-04-0979) 相似文献
18.
The way to compare the efficiencies of different detect strategies (DSs) in the “ping-pong” protocol is studied. The trade-off
between information gain and disturbance is calculated and compared for different DSs. The comparison result primely tallies
with our intuitional analysis. It is shown that the analysis of this trade-off is a feasible way to compare the performances
of different DSs in theory.
Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA01Z419), the National
Natural Science Foundation of China (Grant Nos. 90604023 and 6087319), the National Laboratory for Modern Communications Science
Foundation of China (Grant No. 9140C1101010601), the Natural Science Foundation of Beijing (Grant No. 4072020), and the ISN
Open Foundation. 相似文献
19.
J. Kudrnovský V. Drchal I. Turek C. Blaas P. Weinberger P. Bruno 《Czechoslovak Journal of Physics》1999,49(11):1583-1589
The current-perpendicular-to-plane (CPP) magnetoconductance of a trilayer consisting of a spacer sandwiched between two ideal
leads is described on anab initio level. We employ the transmission matrix formulation of the conductance within the framework of the spin-polarized surface
Green function technique as formulated in terms of the tight-binding linear muffin-tin orbital method. The formalism is extended
to the case of lateral supercells in each layer with random arrangements of atoms which allows to treat both the ballistic
and diffusive transports on equal footing. The application is made to fcc-based Co/Cu/Co(001) trilayers.
Presented at the VIII-th Symposium on Surface Physics, Třešt’ Castle, Czech Republic, June 28 – July 2, 1999.
Financial support for this work was provided by the Grant Agency of the Czech Republic (Project No. 202/97/0598), the Grant
Agency of the Academy of Sciences of the Czech Republic (Project A1010829), the Center for the Computational Materials Science
in Vienna (GZ 45.442 and GZ 45.420), the Austrian BMWV (AKTION WTZ-?sterreich-Tschechien I.23), MŠMT ČR (Project COST P3.70),
and the TMR Network ‘Interface Magnetism’ of the European Commission (Contract No. EMRX-CT96-0089). 相似文献
20.
It is difficult to eliminate the effect of vessel walls and impurities in practical studies of boiling-up of strongly superheated
liquids. Therefore, some doubts are always cast upon validity of experiments and their agreement with the classical theory
of homogeneous stationary nucleation, impairing the verification of theoretical considerations. This paper reports main results
of the theory of homogeneous nucleation and presents formulas for calculating the work of formation of a critical nucleus
by an incline of the accessible superheating boundary on isobars and isotherms. Matching of experimental and theoretical values
of the work of formation was considered as the homogeneous boiling-up criterion. Calculations by isobars and isotherms were
made for some liquids. The theoretical values of the work of formation of a critical nucleus were 1.23–4.5 times higher than
the corresponding empirical values for all the liquids, i.e., they were much higher than the calculation error. Thus, boiling-up
of the studied liquids was not homogeneous and, hence, it did not correspond to the classical theory of nucleation.
The work was financially supported by the President of the Russian Federation (No. NSh-4429.2006.8) and the Russian Foundation
for Basic Research (Grant No. 07-08-00575-a). 相似文献