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1.
In this paper,by using the Brunn-Minkowski-Firey mixed volume theory and dual mixed volume theory,associated with L_p intersection body and dual mixed volume,some dual Brunn-Minkowski inequalities and their isolate forms are established for L_p intersection body about the normalized L_p radial addition and L_p radial linear combination.Some properties of operator Lp are given. 相似文献
2.
Shape-memory TiNi fiber-reinforced/epoxy matrix composites have been fabricated, and the suppression of crack-tip stress intensity
and the change in fracture toughness have been systematically investigated. Stress-strain data for these composite specimens
with notches at various angles and different crack lengths in the transverse direction have been measured in tensile tests.
The stress intensity factor at the crack tip is experimentally determined from photoelastic fringe patterns. The decreases
inK values are attributed to the compressive stress field in the matrix induced when the pre-strains of the TiNi fiber contract
to their initial length upon heating above the austenitic final temperature. We present the influences of the pre-strain of
TiNi fibers and the compressive domain size between a crack tip and fiber on theK value. 相似文献
3.
《Particuology》2008,6(4):252-257
Lithium-aluminum-cobalt-nickel oxide LiAlxCoyNi1xyO2 particles, generally used as cathode of lithium battery, were prepared by chemical coprecipitation from an aqueous solution of LiOH, Al(NO3)3, Co(NO3)2 and Ni(NO3)2 with NH4OH. XRD, SEM and FTIR were used to examine the effect of nickel content on the product. FTIR patterns showed that increase in nickel content decreased the absorption strength of the peak of spinel structure of the product, attributed to the occupation by nickel in the aluminum sites. Particle size and electrical properties of the lithium-aluminum-cobalt-nickel oxide (abbreviated as LACNO) particles were also determined. 相似文献
4.
Petty's conjectured projection inequality is a famous open problem in the theory of convex bodies. In this paper, it is shown that an inequality relating to Lp-version of the Petty's conjectured projection inequality is developed by using the notions of the Lp-mixed volume and the Lp-dual mixed volume, the relation of the Lp-projection body and the geometric body Г-pK, the Bourgain-Milman inequality and the Lp-Bnsemann-Petty inequality. In addition, for each origin-symmetric convex body, by applying the Jensen inequality and the monotonicity of the geometric body Г-pK, the reverses of Lp-version of the Petty's conjectured projection inequality and the Lp-Petty projection inequality are given, respectively. 相似文献
5.
Ding Xie-ping 《应用数学和力学(英文版)》2003,24(6):659-672
A new family of set-valued mappings from a topological space into generalized convex spaces was introduced and studied. By
using the continuous partition of unity theorem and Brouwer fixed point theorem, several existence theorems of maximal elements
for the family of set-valued mappings were proved under noncompact setting of product generalized convex spaces. These theorems
improve, unify and generalize many important results in recent literature.
Contributed by DING Xie-ping
Foundation items: the National Natural Science Foundation of China (19871059); the Natural Science Foundation of Education Department of Sichuan
Province of China ([2000]25)
Biography: DING Xie-ping (1938∼) 相似文献
6.
YusufYayli NergizYaz MuratKemalKaracan ZHOUZhe-wei 《应用数学和力学(英文版)》2004,25(8):898-902
Quaternion is a division ring. It is shown that planes passing through the origin can be made a field with the quaternion product in R3. The Hamiltonian operators help us define the homothetic motions on these planes. New characterizations for these motions are investigated. 相似文献
7.
Lawrence Markus 《Journal of Dynamics and Differential Equations》2007,19(1):133-154
In a celebrated theorem H?lder proved that the Euler Γ-function is differential transcendental, i.e. Γ(z) is not a solution of any (non-trivial) algebraic ordinary differential equation with coefficients that are complex numbers; and we extend his methods to the Riemann ζ-function. Moreover, we conjecture that Γ and ζ are differential independent, i.e. Γ(z) is not a solution of any such algebraic differential equation—even allowing coefficients that are differential polynomials in ζ(z). However, we are able to demonstrate only the partial result that Γ(z) and ζ(sin 2πz) are differential independent. 相似文献
8.
Ding Xie-ping 《应用数学和力学(英文版)》2003,24(9):1017-1024
By applying existence theorems of maximal elements for a family of GB-majorized mappings in a product space of G-convex spaces, some coincidence theorem, Fan-Browder type fixed point theorem
and some existence theorems of solutions for a system of minimax inequalities are proved under noncompact setting of G-convex
spaces. These theorems improve and generalize many important known results in literature.
Contributed by Duping Xie-ping
Foundation items: the National Natural Science Foundation of China (19871059); the Natural Science Foundation of Education Department of Sichuan
Province ([2000]25)
Biography: Duping Xie-ping (1938∼), Professor (E-mail: dingxip@sichu.edu.cn) 相似文献
9.
The electrorheological properties (ER) of some fluids containing particles change extensively under the external electrical
field. This phenomenon is applicable in many industries and equipments, such as clutches and motor driven rotor, which would
transfer the spin to a drive shaft through a thin layer of electrorheological fluid. In this investigation, the effects of
external electrical field on ER properties of non-Newtonian fluids (silicon oil) with the addition of SnO2 and Y2O3 nanoparticles were studied. The ER properties were measured for a wide range of SnO2 and Y2O3 nanoparticle concentrations and DC electrical voltages using concentric cylinder rotary rheometer. Based on the results,
ER properties of nanofluids, e.g., apparent viscosity, shear stress, and yield stress, were enhanced by applying electrical
field and increasing SnO2 and Y2O3 concentrations.
相似文献
S. Gh. EtemadEmail: |
10.
TheT
ε
*
integral was calculated on the surface of single edge notched, three-point bend (SE(B)) specimens using experimentally obtained
displacements. Comparison was made withT
ε
*
calculated with the measured surface displacements andT
ε
*
calculated at several points through the thickness of a finite element (FE) model of the SE(B) specimen. Good comparison
was found between the surfaceT
ε
*
calculated from displacements extracted from the FE model and the surfaceT
ε
*
calculated from experimentally obtained displacements. The computedT
ε
*
integral was also observed to decrease as the crack front was traversed from the surface to the mid-plane of the specimen.
Mid-planeT
ε
*
values tend to be approximately 10% of the surface values. 相似文献
11.
12.
This paper describes a practical method for finding the invariant orbits in J
2 relative dynamics. Working with the Hamiltonian model of the relative motion including the J
2 perturbation, the effective differential correction algorithm for finding periodic orbits in three-body problem is extended
to formation flying of Earth’s orbiters. Rather than using orbital elements, the analysis is done directly in physical space,
which makes a direct connection with physical requirements. The asymptotic behavior of the invariant orbit is indicated by
its stable and unstable manifolds. The period of the relative orbits is proved numerically to be slightly different from the
ascending node period of the leader satellite, and a preliminary explanation for this phenomenon is presented. Then the compatibility
between J
2 invariant orbit and desired relative geometry is considered, and the design procedure for the initial values of the compatible
configuration is proposed. The influences of measure errors on the invariant orbit are also investigated by the Monte–Carlo
simulation.
The project supported by the Innovation Foundation of Beihang University for Ph.D. Graduates, and the National Natural Science
Foundation of China (60535010). 相似文献
13.
Novid Beheshti Alexey A. Burluka Michael Fairweather 《Theoretical and Computational Fluid Dynamics》2007,21(5):381-397
In a series of recent works, R. Borghi and co-workers proposed a new Eulerian model of two-phase turbulent flows which introduced
a transport equation for the average area of the liquid–gas interface. This work is devoted to the assessment of this model’s
ability to predict the effects of liquid properties and injection regimes on the atomisation quality. Air-assisted atomisation,
for which extensive experimental data are available, is chosen as a test case. It is shown that the model predictions are
in good agreement with the observed trends for a wide range of variations of the liquid properties, such as density and surface
tension, as well as the injection regimes, defined by the liquid and gas jet exit velocities.
相似文献
14.
Nylon-6 is an important engineering polymer that, in its fully spherulitic (bulk) form, has many applications in gears, rollers,
and other long life cycle components. In 1993, Toyota commercialized a nylon-6/clay nanocomposite out of which it produced
the timing belt cover for the Camry. Although these hybrid nanocomposites show significant improvements in their mechanical
response characteristics, including yield strength and heat distortion temperature, little is known about the degradation
of these properties due to environmental pollutants like NO
x
. Nylon-6 fibers are severely degraded by interaction with NO
x
and other pollutants, showing a strong synergy between applied load and environmental degradation. While the nanocomposites
show a significant reduction in permeability of gases and water due to the incorporation of lamellar clay, their susceptibility
to nondiffusional mechano-chemical degradation is unknown. The fracture toughness of these nylon-6/clay nanocomposites increases,
not as a function of clay content, but as a function of the volume of nylon-6 polymer chains influenced by the clay lamellae
surfaces. Both the clay and the constrained volume offer the nanocomposites some protection from the deleterious effects of
NO
x
. The time-to-failure at a given stress intensity factor as a function of clay content and constrained volume is discussed
along with fracture toughness of the materials. 相似文献
15.
Periodic solution of m order linear neutral equations with constant coefficient and time delays was studied. Existence and
uniqueness of 2 T-periodic solutions for the equation were discussed by using the method of Fourier series. Some new necessary
and sufficient conditions of existence and uniqueness of 2T-periodic solutions for the equation are obtained. The main result
is used widely. It contains results in some correlation paper for its special case, improves and extends the main results
in them. Existence of periodic solution for the equation in larger number of particular case can be checked by using the result,
but cannot be checked in another paper. In other words, the main result in this paper is most generalized for (1), the better
result cannot be found by using the same method.
Foundation item: the Natural Science Foundation of Yunnan Education Committee (990002)
Biography: ZHANG Bao-sheng (1962-) 相似文献
16.
G. Seregin 《Journal of Mathematical Fluid Mechanics》2007,9(1):34-43
A sufficient condition of regularity for solutions to the Navier–Stokes equations is proved. It generalizes the so-called
L
3,∞-case. 相似文献
17.
A new class of g-η-monotone mappings and a class of generalized implicit variational-like inclusions involving g-η-monotone mappings are introduced. The resolvent operator of g-η-monotone mappings is defined and its Lipschitz continuity is presented. An iterative algorithm for approximating the solutions of generalized implicit variational-like inclusions is suggested and analyzed. The convergence of iterative sequences generated by the algorithm is also proved. 相似文献
18.
Anjan Biswas 《Nonlinear dynamics》2010,59(3):423-426
This paper integrates the regularized long-wave equation with power-law nonlinearity using the solitary-wave ansatz. A few
of the conserved quantities are calculated by using the 1-soliton solution. This technique is then extended to obtain the
solitary-wave solution of the R(m,n) equation and a conserved quantity is also calculated for this generalized equation. 相似文献
19.
A new method for calculating the hysteretic relationship between hydraulic conductivity (K) and suction (S) is proposed. This method uses the experimental (K–S) data of the main wetting and drying branches and predicts satisfactorily the scanning drying and wetting curves. The proposed
method is applicable to those porous media where the hysteretic Θ–S relationship complies with the independent domain concept. 相似文献
20.
A recently proposed “Projection-based Digital Volume Correlation” (P-DVC) method is extended in this work to a cone-beam lab-tomograph in which a mechanical test is performed. This consists of a crack propagation test in an elastic-brittle gypsum specimen. Kinematic analysis is performed based on a reduced finite element modeling for which the appropriate boundary conditions and crack propagation stage are determined from the radiographs. By considering only two projections per loading step, an integrated model-based analysis of the entire test provides a full space and time identification of the kinematics, including the crack position and the determination of two material parameters. This is achieved with a drastic reduction in the acquisition time compared to classical digital volume correlation analysis. In the examples presented, the acquisition time was reduced by a factor of 350. 相似文献