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1.
An experimental method for determining the real-time depth of laser-drilled holes is presented. The proposed method involves
detecting the laser-induced optoacoustic waves generated during the interaction of the laser beam with the material. Our optodynamic
study involved measuring the propagation times of these waves as they traveled through the material and analyzing their temporal
behavior during the drilling process. The experimental observations revealed an exponential relationship between the propagation
time of the longitudinal stress wave and the number of consecutive laser pulses.
Received: 25 October 2001 / Accepted: 27 October 2001 / Published online: 20 December 2001 相似文献
2.
Karin Cvetko-Vah 《Semigroup Forum》2004,68(2):268-279
Given a ring $R$, let $S\subseteq R$ be a pure multiplicative band that is
closed under the cubic join operation $x\nabla y = x+y+yx-xyx-yxy.$ We show that
$\left( S,\cdot,\nabla\right) $ forms a pure skew lattice if and only if $S$
satisfies the polynomial identity $\left(xy-yx\right)^{2}z = z\left(xy-yx\right)^{2}$.
We also examine properties of pure skew lattices
in rings. 相似文献
3.
《Journal of Electrostatics》2006,64(2):137-146
In this paper, we propose new circuit design options for increasing the “effective” failure voltage (Vt2) of both NMOS and PMOS output buffer transistors, thereby helping to protect these fragile devices. Using experimental data, device and circuit simulations, we demonstrate how placing a series resistor and either a bias circuit for the buffer gates or secondary ESD diodes may significantly increase Vt2. 相似文献
4.
We study the family of simple graphs whose number of primitive cycles equals its cycle rank. Then we study toric ideals of simple and oriented graphs. 相似文献
5.
The surgery obstruction of a normal map to a simple Poincaré pair (X, Y) lies in the relative surgery obstruction group L *(π 1(Y) → π 1(X)). A well-known result of Wall, the so-called π-π-theorem, states that in higher dimensions a normal map of a manifold with boundary to a simple Poincaré pair with π 1(X) ? π 1(Y) is normally bordant to a simple homotopy equivalence of pairs. In order to study normal maps to a manifold with a submanifold, Wall introduced the surgery obstruction groups LP * for manifold pairs and splitting obstruction groups LS *. In the present paper, we formulate and prove for manifold pairs with boundary results similar to the π-π-theorem. We give direct geometric proofs, which are based on the original statements of Wall’s results and apply obtained results to investigate surgery on filtered manifolds. 相似文献
6.
The complete set of self-consistent parameters of nominally undoped LiNbO3 crystals of congruent composition that describe the electro-optic, piezoelectric, elasto-optic, elastic, and dielectric response
has been determined by numerically evaluating available measurements. The parameters were determined at room temperature and
consist of the low-frequency clamped dielectric constants εS
ij, elastic stiffness constants at constant electric field CE
ijkl, piezoelectric stress coefficients eijk, elasto-optic constants at constant electric field pE
ijkl, and clamped electro-optic coefficients rS
ijk. It is shown that the complete set is required for calculating the effective electro-optic coefficients and dielectric constants
in photorefractive applications of LiNbO3.
Received: 4 January 2002 / Revised version: 1 February 2002 / Published online: 14 March 2002 相似文献
7.
Nanostructured lanthanum–strontium manganites were synthesized using two different co-precipitation approaches, one in bulk solution, and the other in reverse micelles of CTAB/1-hexanol/water microemulsion. In both cases, precursor cations were precipitated by using oxalic acid. The properties of the materials synthesized by using these two methods were compared in order to reveal potential advantages of the microemulsion-assisted approach. The influence of the annealing conditions on the properties of synthesized manganites was investigated by using X-ray diffraction, transmission electron microscopy, differential thermal analysis, thermogravimetric analysis and magnetic measurements. 相似文献
8.
9.
Improved sample wettability was obtained by oxygen plasma functionalization of pyrolytic graphite. The samples were exposed to highly dissociated oxygen plasma with the density of 1 × 1016 m−3, the electron temperature of about 5.5 eV and the density of neutral oxygen atoms of 8 × 1021 m−3 for 20 s. The surface wettability was measured by a contact angle of water drop. The contact angle dropped from original 112° down to about 1°. The functional groups were detected by XPS analyses. The survey spectrum showed a substantial increase of oxygen concentration on the surface, while high-resolution analyses showed additional oxygen was bonded onto the graphite surface in the form of C-O polar functional group responsible for the increase of the surface energy. 相似文献
10.
In this paper we discuss some instances where dense matrix techniques can be utilized within a sparse simplex linear programming solver. The main emphasis is on the use of the Schur complement matrix as a part of the basis matrix representation. This approach enables to represent the basis matrix as an easily invertible sparse matrix and one or more dense Schur complement matrices. We describe our variant of this method which uses updating of the QR factorization of the Schur complement matrix. We also discuss some implementation issues of the LP software package which is based on this approach. 相似文献